blob: fc2ceae61db2d0f6c31f6e6e1da35b2fce6a79db [file] [log] [blame]
Dave Airliead7f8a12014-06-05 14:01:32 +10001/*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
Sean Paule38c2982020-08-19 10:31:24 -040023#include <linux/bitfield.h>
Dave Airliead7f8a12014-06-05 14:01:32 +100024#include <linux/delay.h>
Dave Airliead7f8a12014-06-05 14:01:32 +100025#include <linux/errno.h>
Jani Nikula580fc132019-05-06 12:52:47 +030026#include <linux/i2c.h>
27#include <linux/init.h>
28#include <linux/kernel.h>
Sean Paule38c2982020-08-19 10:31:24 -040029#include <linux/random.h>
Dave Airliead7f8a12014-06-05 14:01:32 +100030#include <linux/sched.h>
Dave Airlie75bc08a2014-07-09 11:15:09 +100031#include <linux/seq_file.h>
Lyude Paul873a95e2020-04-03 15:47:15 -040032#include <linux/iopoll.h>
Dave Airliead7f8a12014-06-05 14:01:32 +100033
Lyude Paul12a280c2019-06-20 17:59:25 -040034#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
Chenwandun68acde762019-10-31 17:43:49 +080035#include <linux/stacktrace.h>
Lyude Paul12a280c2019-06-20 17:59:25 -040036#include <linux/sort.h>
37#include <linux/timekeeping.h>
38#include <linux/math64.h>
39#endif
40
Thomas Zimmermannda683862022-04-21 09:31:02 +020041#include <drm/display/drm_dp_mst_helper.h>
Ville Syrjäläa4370c72017-07-12 18:51:02 +030042#include <drm/drm_atomic.h>
43#include <drm/drm_atomic_helper.h>
Jani Nikula580fc132019-05-06 12:52:47 +030044#include <drm/drm_drv.h>
Ville Syrjälä255490f92022-06-14 12:02:45 +030045#include <drm/drm_edid.h>
Imre Deak191dc432023-11-16 15:18:31 +020046#include <drm/drm_fixed.h>
Jani Nikula580fc132019-05-06 12:52:47 +030047#include <drm/drm_print.h>
Daniel Vetterfcd70cd2019-01-17 22:03:34 +010048#include <drm/drm_probe_helper.h>
Dave Airliead7f8a12014-06-05 14:01:32 +100049
Thomas Zimmermann3681eb22022-01-14 12:45:32 +010050#include "drm_dp_helper_internal.h"
Lyude Paul2f015ec2019-09-03 16:45:45 -040051#include "drm_dp_mst_topology_internal.h"
Ville Syrjälä562836a22019-07-23 19:28:01 -040052
Dave Airliead7f8a12014-06-05 14:01:32 +100053/**
54 * DOC: dp mst helper
55 *
56 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
57 * protocol. The helpers contain a topology manager and bandwidth manager.
58 * The helpers encapsulate the sending and received of sideband msgs.
59 */
Lyude Paul9408cc92019-06-17 16:37:18 -040060struct drm_dp_pending_up_req {
61 struct drm_dp_sideband_msg_hdr hdr;
62 struct drm_dp_sideband_msg_req_body msg;
63 struct list_head next;
64};
65
Dave Airliead7f8a12014-06-05 14:01:32 +100066static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
67 char *buf);
Dave Airliead7f8a12014-06-05 14:01:32 +100068
Lyude Pauld0757af2019-01-10 19:53:28 -050069static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port);
Dave Airliead7f8a12014-06-05 14:01:32 +100070
71static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
Lyude Paul4d07b0b2022-08-17 15:38:46 -040072 int id, u8 start_slot, u8 num_slots);
Dave Airliead7f8a12014-06-05 14:01:32 +100073
Ville Syrjälä562836a22019-07-23 19:28:01 -040074static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
75 struct drm_dp_mst_port *port,
76 int offset, int size, u8 *bytes);
Dave Airliead7f8a12014-06-05 14:01:32 +100077static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
78 struct drm_dp_mst_port *port,
79 int offset, int size, u8 *bytes);
80
Lyude Paul6f85f732019-06-17 19:57:33 -040081static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
82 struct drm_dp_mst_branch *mstb);
Sean Paulf7948902019-08-28 20:09:44 -040083
84static void
85drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr,
86 struct drm_dp_mst_branch *mstb);
87
Dave Airliead7f8a12014-06-05 14:01:32 +100088static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
89 struct drm_dp_mst_branch *mstb,
90 struct drm_dp_mst_port *port);
91static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
92 u8 *guid);
93
Imre Deakd8bd15b2020-06-08 00:25:21 +030094static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port);
95static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port);
Dave Airliead7f8a12014-06-05 14:01:32 +100096static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
Ville Syrjälä3dadbd22019-01-22 22:03:01 +020097
Wayne Lin3769e4c2021-06-16 11:55:01 +080098static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port,
99 struct drm_dp_mst_branch *branch);
100
Lyude Paul2f015ec2019-09-03 16:45:45 -0400101#define DBG_PREFIX "[dp_mst]"
102
Ville Syrjälä3dadbd22019-01-22 22:03:01 +0200103#define DP_STR(x) [DP_ ## x] = #x
104
105static const char *drm_dp_mst_req_type_str(u8 req_type)
106{
107 static const char * const req_type_str[] = {
108 DP_STR(GET_MSG_TRANSACTION_VERSION),
109 DP_STR(LINK_ADDRESS),
110 DP_STR(CONNECTION_STATUS_NOTIFY),
111 DP_STR(ENUM_PATH_RESOURCES),
112 DP_STR(ALLOCATE_PAYLOAD),
113 DP_STR(QUERY_PAYLOAD),
114 DP_STR(RESOURCE_STATUS_NOTIFY),
115 DP_STR(CLEAR_PAYLOAD_ID_TABLE),
116 DP_STR(REMOTE_DPCD_READ),
117 DP_STR(REMOTE_DPCD_WRITE),
118 DP_STR(REMOTE_I2C_READ),
119 DP_STR(REMOTE_I2C_WRITE),
120 DP_STR(POWER_UP_PHY),
121 DP_STR(POWER_DOWN_PHY),
122 DP_STR(SINK_EVENT_NOTIFY),
123 DP_STR(QUERY_STREAM_ENC_STATUS),
124 };
125
126 if (req_type >= ARRAY_SIZE(req_type_str) ||
127 !req_type_str[req_type])
128 return "unknown";
129
130 return req_type_str[req_type];
131}
132
133#undef DP_STR
134#define DP_STR(x) [DP_NAK_ ## x] = #x
135
136static const char *drm_dp_mst_nak_reason_str(u8 nak_reason)
137{
138 static const char * const nak_reason_str[] = {
139 DP_STR(WRITE_FAILURE),
140 DP_STR(INVALID_READ),
141 DP_STR(CRC_FAILURE),
142 DP_STR(BAD_PARAM),
143 DP_STR(DEFER),
144 DP_STR(LINK_FAILURE),
145 DP_STR(NO_RESOURCES),
146 DP_STR(DPCD_FAIL),
147 DP_STR(I2C_NAK),
148 DP_STR(ALLOCATE_FAIL),
149 };
150
151 if (nak_reason >= ARRAY_SIZE(nak_reason_str) ||
152 !nak_reason_str[nak_reason])
153 return "unknown";
154
155 return nak_reason_str[nak_reason];
156}
157
158#undef DP_STR
Lyude Paul2f015ec2019-09-03 16:45:45 -0400159#define DP_STR(x) [DRM_DP_SIDEBAND_TX_ ## x] = #x
160
161static const char *drm_dp_mst_sideband_tx_state_str(int state)
162{
163 static const char * const sideband_reason_str[] = {
164 DP_STR(QUEUED),
165 DP_STR(START_SEND),
166 DP_STR(SENT),
167 DP_STR(RX),
168 DP_STR(TIMEOUT),
169 };
170
171 if (state >= ARRAY_SIZE(sideband_reason_str) ||
172 !sideband_reason_str[state])
173 return "unknown";
174
175 return sideband_reason_str[state];
176}
177
178static int
179drm_dp_mst_rad_to_str(const u8 rad[8], u8 lct, char *out, size_t len)
180{
181 int i;
182 u8 unpacked_rad[16];
183
184 for (i = 0; i < lct; i++) {
185 if (i % 2)
186 unpacked_rad[i] = rad[i / 2] >> 4;
187 else
188 unpacked_rad[i] = rad[i / 2] & BIT_MASK(4);
189 }
190
191 /* TODO: Eventually add something to printk so we can format the rad
192 * like this: 1.2.3
193 */
194 return snprintf(out, len, "%*phC", lct, unpacked_rad);
195}
Ville Syrjälä3dadbd22019-01-22 22:03:01 +0200196
Dave Airliead7f8a12014-06-05 14:01:32 +1000197/* sideband msg handling */
198static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
199{
200 u8 bitmask = 0x80;
201 u8 bitshift = 7;
202 u8 array_index = 0;
203 int number_of_bits = num_nibbles * 4;
204 u8 remainder = 0;
205
206 while (number_of_bits != 0) {
207 number_of_bits--;
208 remainder <<= 1;
209 remainder |= (data[array_index] & bitmask) >> bitshift;
210 bitmask >>= 1;
211 bitshift--;
212 if (bitmask == 0) {
213 bitmask = 0x80;
214 bitshift = 7;
215 array_index++;
216 }
217 if ((remainder & 0x10) == 0x10)
218 remainder ^= 0x13;
219 }
220
221 number_of_bits = 4;
222 while (number_of_bits != 0) {
223 number_of_bits--;
224 remainder <<= 1;
225 if ((remainder & 0x10) != 0)
226 remainder ^= 0x13;
227 }
228
229 return remainder;
230}
231
232static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
233{
234 u8 bitmask = 0x80;
235 u8 bitshift = 7;
236 u8 array_index = 0;
237 int number_of_bits = number_of_bytes * 8;
238 u16 remainder = 0;
239
240 while (number_of_bits != 0) {
241 number_of_bits--;
242 remainder <<= 1;
243 remainder |= (data[array_index] & bitmask) >> bitshift;
244 bitmask >>= 1;
245 bitshift--;
246 if (bitmask == 0) {
247 bitmask = 0x80;
248 bitshift = 7;
249 array_index++;
250 }
251 if ((remainder & 0x100) == 0x100)
252 remainder ^= 0xd5;
253 }
254
255 number_of_bits = 8;
256 while (number_of_bits != 0) {
257 number_of_bits--;
258 remainder <<= 1;
259 if ((remainder & 0x100) != 0)
260 remainder ^= 0xd5;
261 }
262
263 return remainder & 0xff;
264}
265static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
266{
267 u8 size = 3;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530268
Dave Airliead7f8a12014-06-05 14:01:32 +1000269 size += (hdr->lct / 2);
270 return size;
271}
272
273static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
274 u8 *buf, int *len)
275{
276 int idx = 0;
277 int i;
278 u8 crc4;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530279
Dave Airliead7f8a12014-06-05 14:01:32 +1000280 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
281 for (i = 0; i < (hdr->lct / 2); i++)
282 buf[idx++] = hdr->rad[i];
283 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
284 (hdr->msg_len & 0x3f);
285 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
286
287 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
288 buf[idx - 1] |= (crc4 & 0xf);
289
290 *len = idx;
291}
292
Lyude Paul3a08f532021-04-23 14:43:09 -0400293static bool drm_dp_decode_sideband_msg_hdr(const struct drm_dp_mst_topology_mgr *mgr,
294 struct drm_dp_sideband_msg_hdr *hdr,
Dave Airliead7f8a12014-06-05 14:01:32 +1000295 u8 *buf, int buflen, u8 *hdrlen)
296{
297 u8 crc4;
298 u8 len;
299 int i;
300 u8 idx;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530301
Dave Airliead7f8a12014-06-05 14:01:32 +1000302 if (buf[0] == 0)
303 return false;
304 len = 3;
305 len += ((buf[0] & 0xf0) >> 4) / 2;
306 if (len > buflen)
307 return false;
308 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
309
310 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
Lyude Paul3a08f532021-04-23 14:43:09 -0400311 drm_dbg_kms(mgr->dev, "crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
Dave Airliead7f8a12014-06-05 14:01:32 +1000312 return false;
313 }
314
315 hdr->lct = (buf[0] & 0xf0) >> 4;
316 hdr->lcr = (buf[0] & 0xf);
317 idx = 1;
318 for (i = 0; i < (hdr->lct / 2); i++)
319 hdr->rad[i] = buf[idx++];
320 hdr->broadcast = (buf[idx] >> 7) & 0x1;
321 hdr->path_msg = (buf[idx] >> 6) & 0x1;
322 hdr->msg_len = buf[idx] & 0x3f;
323 idx++;
324 hdr->somt = (buf[idx] >> 7) & 0x1;
325 hdr->eomt = (buf[idx] >> 6) & 0x1;
326 hdr->seqno = (buf[idx] >> 4) & 0x1;
327 idx++;
328 *hdrlen = idx;
329 return true;
330}
331
Lyude Paul2f015ec2019-09-03 16:45:45 -0400332void
333drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req,
334 struct drm_dp_sideband_msg_tx *raw)
Dave Airliead7f8a12014-06-05 14:01:32 +1000335{
336 int idx = 0;
337 int i;
338 u8 *buf = raw->msg;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530339
Dave Airliead7f8a12014-06-05 14:01:32 +1000340 buf[idx++] = req->req_type & 0x7f;
341
342 switch (req->req_type) {
343 case DP_ENUM_PATH_RESOURCES:
Lyude Paulaa2a2fe2019-09-03 17:57:02 -0400344 case DP_POWER_DOWN_PHY:
345 case DP_POWER_UP_PHY:
Dave Airliead7f8a12014-06-05 14:01:32 +1000346 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
347 idx++;
348 break;
349 case DP_ALLOCATE_PAYLOAD:
350 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
351 (req->u.allocate_payload.number_sdp_streams & 0xf);
352 idx++;
353 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
354 idx++;
355 buf[idx] = (req->u.allocate_payload.pbn >> 8);
356 idx++;
357 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
358 idx++;
359 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
360 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
361 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
362 idx++;
363 }
364 if (req->u.allocate_payload.number_sdp_streams & 1) {
365 i = req->u.allocate_payload.number_sdp_streams - 1;
366 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
367 idx++;
368 }
369 break;
370 case DP_QUERY_PAYLOAD:
371 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
372 idx++;
373 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
374 idx++;
375 break;
376 case DP_REMOTE_DPCD_READ:
377 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
378 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
379 idx++;
380 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
381 idx++;
382 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
383 idx++;
384 buf[idx] = (req->u.dpcd_read.num_bytes);
385 idx++;
386 break;
387
388 case DP_REMOTE_DPCD_WRITE:
389 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
390 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
391 idx++;
392 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
393 idx++;
394 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
395 idx++;
396 buf[idx] = (req->u.dpcd_write.num_bytes);
397 idx++;
398 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
399 idx += req->u.dpcd_write.num_bytes;
400 break;
401 case DP_REMOTE_I2C_READ:
402 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
403 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
404 idx++;
405 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
406 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
407 idx++;
408 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
409 idx++;
410 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
411 idx += req->u.i2c_read.transactions[i].num_bytes;
412
Wayne Linc4e4fcc2020-01-03 13:50:01 +0800413 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 4;
Dave Airliead7f8a12014-06-05 14:01:32 +1000414 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
415 idx++;
416 }
417 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
418 idx++;
419 buf[idx] = (req->u.i2c_read.num_bytes_read);
420 idx++;
421 break;
422
423 case DP_REMOTE_I2C_WRITE:
424 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
425 idx++;
426 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
427 idx++;
428 buf[idx] = (req->u.i2c_write.num_bytes);
429 idx++;
430 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
431 idx += req->u.i2c_write.num_bytes;
432 break;
Sean Paule38c2982020-08-19 10:31:24 -0400433 case DP_QUERY_STREAM_ENC_STATUS: {
434 const struct drm_dp_query_stream_enc_status *msg;
435
436 msg = &req->u.enc_status;
437 buf[idx] = msg->stream_id;
438 idx++;
439 memcpy(&buf[idx], msg->client_id, sizeof(msg->client_id));
440 idx += sizeof(msg->client_id);
441 buf[idx] = 0;
442 buf[idx] |= FIELD_PREP(GENMASK(1, 0), msg->stream_event);
443 buf[idx] |= msg->valid_stream_event ? BIT(2) : 0;
444 buf[idx] |= FIELD_PREP(GENMASK(4, 3), msg->stream_behavior);
445 buf[idx] |= msg->valid_stream_behavior ? BIT(5) : 0;
446 idx++;
447 }
448 break;
Dave Airliead7f8a12014-06-05 14:01:32 +1000449 }
450 raw->cur_len = idx;
451}
Lyude Paul2f015ec2019-09-03 16:45:45 -0400452EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_encode_sideband_req);
453
454/* Decode a sideband request we've encoded, mainly used for debugging */
455int
456drm_dp_decode_sideband_req(const struct drm_dp_sideband_msg_tx *raw,
457 struct drm_dp_sideband_msg_req_body *req)
458{
459 const u8 *buf = raw->msg;
460 int i, idx = 0;
461
462 req->req_type = buf[idx++] & 0x7f;
463 switch (req->req_type) {
464 case DP_ENUM_PATH_RESOURCES:
465 case DP_POWER_DOWN_PHY:
466 case DP_POWER_UP_PHY:
467 req->u.port_num.port_number = (buf[idx] >> 4) & 0xf;
468 break;
469 case DP_ALLOCATE_PAYLOAD:
470 {
471 struct drm_dp_allocate_payload *a =
472 &req->u.allocate_payload;
473
474 a->number_sdp_streams = buf[idx] & 0xf;
475 a->port_number = (buf[idx] >> 4) & 0xf;
476
477 WARN_ON(buf[++idx] & 0x80);
478 a->vcpi = buf[idx] & 0x7f;
479
480 a->pbn = buf[++idx] << 8;
481 a->pbn |= buf[++idx];
482
483 idx++;
484 for (i = 0; i < a->number_sdp_streams; i++) {
485 a->sdp_stream_sink[i] =
486 (buf[idx + (i / 2)] >> ((i % 2) ? 0 : 4)) & 0xf;
487 }
488 }
489 break;
490 case DP_QUERY_PAYLOAD:
491 req->u.query_payload.port_number = (buf[idx] >> 4) & 0xf;
492 WARN_ON(buf[++idx] & 0x80);
493 req->u.query_payload.vcpi = buf[idx] & 0x7f;
494 break;
495 case DP_REMOTE_DPCD_READ:
496 {
497 struct drm_dp_remote_dpcd_read *r = &req->u.dpcd_read;
498
499 r->port_number = (buf[idx] >> 4) & 0xf;
500
501 r->dpcd_address = (buf[idx] << 16) & 0xf0000;
502 r->dpcd_address |= (buf[++idx] << 8) & 0xff00;
503 r->dpcd_address |= buf[++idx] & 0xff;
504
505 r->num_bytes = buf[++idx];
506 }
507 break;
508 case DP_REMOTE_DPCD_WRITE:
509 {
510 struct drm_dp_remote_dpcd_write *w =
511 &req->u.dpcd_write;
512
513 w->port_number = (buf[idx] >> 4) & 0xf;
514
515 w->dpcd_address = (buf[idx] << 16) & 0xf0000;
516 w->dpcd_address |= (buf[++idx] << 8) & 0xff00;
517 w->dpcd_address |= buf[++idx] & 0xff;
518
519 w->num_bytes = buf[++idx];
520
521 w->bytes = kmemdup(&buf[++idx], w->num_bytes,
522 GFP_KERNEL);
523 if (!w->bytes)
524 return -ENOMEM;
525 }
526 break;
527 case DP_REMOTE_I2C_READ:
528 {
529 struct drm_dp_remote_i2c_read *r = &req->u.i2c_read;
530 struct drm_dp_remote_i2c_read_tx *tx;
531 bool failed = false;
532
533 r->num_transactions = buf[idx] & 0x3;
534 r->port_number = (buf[idx] >> 4) & 0xf;
535 for (i = 0; i < r->num_transactions; i++) {
536 tx = &r->transactions[i];
537
538 tx->i2c_dev_id = buf[++idx] & 0x7f;
539 tx->num_bytes = buf[++idx];
540 tx->bytes = kmemdup(&buf[++idx],
541 tx->num_bytes,
542 GFP_KERNEL);
543 if (!tx->bytes) {
544 failed = true;
545 break;
546 }
547 idx += tx->num_bytes;
548 tx->no_stop_bit = (buf[idx] >> 5) & 0x1;
549 tx->i2c_transaction_delay = buf[idx] & 0xf;
550 }
551
552 if (failed) {
Colin Ian King2c8bc912019-11-20 17:35:09 +0000553 for (i = 0; i < r->num_transactions; i++) {
554 tx = &r->transactions[i];
Lyude Paul2f015ec2019-09-03 16:45:45 -0400555 kfree(tx->bytes);
Colin Ian King2c8bc912019-11-20 17:35:09 +0000556 }
Lyude Paul2f015ec2019-09-03 16:45:45 -0400557 return -ENOMEM;
558 }
559
560 r->read_i2c_device_id = buf[++idx] & 0x7f;
561 r->num_bytes_read = buf[++idx];
562 }
563 break;
564 case DP_REMOTE_I2C_WRITE:
565 {
566 struct drm_dp_remote_i2c_write *w = &req->u.i2c_write;
567
568 w->port_number = (buf[idx] >> 4) & 0xf;
569 w->write_i2c_device_id = buf[++idx] & 0x7f;
570 w->num_bytes = buf[++idx];
571 w->bytes = kmemdup(&buf[++idx], w->num_bytes,
572 GFP_KERNEL);
573 if (!w->bytes)
574 return -ENOMEM;
575 }
576 break;
Sean Paule38c2982020-08-19 10:31:24 -0400577 case DP_QUERY_STREAM_ENC_STATUS:
578 req->u.enc_status.stream_id = buf[idx++];
579 for (i = 0; i < sizeof(req->u.enc_status.client_id); i++)
580 req->u.enc_status.client_id[i] = buf[idx++];
581
582 req->u.enc_status.stream_event = FIELD_GET(GENMASK(1, 0),
583 buf[idx]);
584 req->u.enc_status.valid_stream_event = FIELD_GET(BIT(2),
585 buf[idx]);
586 req->u.enc_status.stream_behavior = FIELD_GET(GENMASK(4, 3),
587 buf[idx]);
588 req->u.enc_status.valid_stream_behavior = FIELD_GET(BIT(5),
589 buf[idx]);
590 break;
Lyude Paul2f015ec2019-09-03 16:45:45 -0400591 }
592
593 return 0;
594}
595EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_decode_sideband_req);
596
597void
598drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req,
599 int indent, struct drm_printer *printer)
600{
601 int i;
602
603#define P(f, ...) drm_printf_indent(printer, indent, f, ##__VA_ARGS__)
604 if (req->req_type == DP_LINK_ADDRESS) {
605 /* No contents to print */
606 P("type=%s\n", drm_dp_mst_req_type_str(req->req_type));
607 return;
608 }
609
610 P("type=%s contents:\n", drm_dp_mst_req_type_str(req->req_type));
611 indent++;
612
613 switch (req->req_type) {
614 case DP_ENUM_PATH_RESOURCES:
615 case DP_POWER_DOWN_PHY:
616 case DP_POWER_UP_PHY:
617 P("port=%d\n", req->u.port_num.port_number);
618 break;
619 case DP_ALLOCATE_PAYLOAD:
620 P("port=%d vcpi=%d pbn=%d sdp_streams=%d %*ph\n",
621 req->u.allocate_payload.port_number,
622 req->u.allocate_payload.vcpi, req->u.allocate_payload.pbn,
623 req->u.allocate_payload.number_sdp_streams,
624 req->u.allocate_payload.number_sdp_streams,
625 req->u.allocate_payload.sdp_stream_sink);
626 break;
627 case DP_QUERY_PAYLOAD:
628 P("port=%d vcpi=%d\n",
629 req->u.query_payload.port_number,
630 req->u.query_payload.vcpi);
631 break;
632 case DP_REMOTE_DPCD_READ:
633 P("port=%d dpcd_addr=%05x len=%d\n",
634 req->u.dpcd_read.port_number, req->u.dpcd_read.dpcd_address,
635 req->u.dpcd_read.num_bytes);
636 break;
637 case DP_REMOTE_DPCD_WRITE:
638 P("port=%d addr=%05x len=%d: %*ph\n",
639 req->u.dpcd_write.port_number,
640 req->u.dpcd_write.dpcd_address,
641 req->u.dpcd_write.num_bytes, req->u.dpcd_write.num_bytes,
642 req->u.dpcd_write.bytes);
643 break;
644 case DP_REMOTE_I2C_READ:
645 P("port=%d num_tx=%d id=%d size=%d:\n",
646 req->u.i2c_read.port_number,
647 req->u.i2c_read.num_transactions,
648 req->u.i2c_read.read_i2c_device_id,
649 req->u.i2c_read.num_bytes_read);
650
651 indent++;
652 for (i = 0; i < req->u.i2c_read.num_transactions; i++) {
653 const struct drm_dp_remote_i2c_read_tx *rtx =
654 &req->u.i2c_read.transactions[i];
655
656 P("%d: id=%03d size=%03d no_stop_bit=%d tx_delay=%03d: %*ph\n",
657 i, rtx->i2c_dev_id, rtx->num_bytes,
658 rtx->no_stop_bit, rtx->i2c_transaction_delay,
659 rtx->num_bytes, rtx->bytes);
660 }
661 break;
662 case DP_REMOTE_I2C_WRITE:
663 P("port=%d id=%d size=%d: %*ph\n",
664 req->u.i2c_write.port_number,
665 req->u.i2c_write.write_i2c_device_id,
666 req->u.i2c_write.num_bytes, req->u.i2c_write.num_bytes,
667 req->u.i2c_write.bytes);
668 break;
Sean Paule38c2982020-08-19 10:31:24 -0400669 case DP_QUERY_STREAM_ENC_STATUS:
670 P("stream_id=%u client_id=%*ph stream_event=%x "
671 "valid_event=%d stream_behavior=%x valid_behavior=%d",
672 req->u.enc_status.stream_id,
673 (int)ARRAY_SIZE(req->u.enc_status.client_id),
674 req->u.enc_status.client_id, req->u.enc_status.stream_event,
675 req->u.enc_status.valid_stream_event,
676 req->u.enc_status.stream_behavior,
677 req->u.enc_status.valid_stream_behavior);
678 break;
Lyude Paul2f015ec2019-09-03 16:45:45 -0400679 default:
680 P("???\n");
681 break;
682 }
683#undef P
684}
685EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_dump_sideband_msg_req_body);
686
687static inline void
688drm_dp_mst_dump_sideband_msg_tx(struct drm_printer *p,
689 const struct drm_dp_sideband_msg_tx *txmsg)
690{
691 struct drm_dp_sideband_msg_req_body req;
692 char buf[64];
693 int ret;
694 int i;
695
696 drm_dp_mst_rad_to_str(txmsg->dst->rad, txmsg->dst->lct, buf,
697 sizeof(buf));
698 drm_printf(p, "txmsg cur_offset=%x cur_len=%x seqno=%x state=%s path_msg=%d dst=%s\n",
699 txmsg->cur_offset, txmsg->cur_len, txmsg->seqno,
700 drm_dp_mst_sideband_tx_state_str(txmsg->state),
701 txmsg->path_msg, buf);
702
703 ret = drm_dp_decode_sideband_req(txmsg, &req);
704 if (ret) {
705 drm_printf(p, "<failed to decode sideband req: %d>\n", ret);
706 return;
707 }
708 drm_dp_dump_sideband_msg_req_body(&req, 1, p);
709
710 switch (req.req_type) {
711 case DP_REMOTE_DPCD_WRITE:
712 kfree(req.u.dpcd_write.bytes);
713 break;
714 case DP_REMOTE_I2C_READ:
715 for (i = 0; i < req.u.i2c_read.num_transactions; i++)
716 kfree(req.u.i2c_read.transactions[i].bytes);
717 break;
718 case DP_REMOTE_I2C_WRITE:
719 kfree(req.u.i2c_write.bytes);
720 break;
721 }
722}
Dave Airliead7f8a12014-06-05 14:01:32 +1000723
724static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
725{
726 u8 crc4;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530727
Dave Airliead7f8a12014-06-05 14:01:32 +1000728 crc4 = drm_dp_msg_data_crc4(msg, len);
729 msg[len] = crc4;
730}
731
732static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
733 struct drm_dp_sideband_msg_tx *raw)
734{
735 int idx = 0;
736 u8 *buf = raw->msg;
737
738 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
739
740 raw->cur_len = idx;
741}
742
Sean Paul21a729d2020-02-13 16:15:18 -0500743static int drm_dp_sideband_msg_set_header(struct drm_dp_sideband_msg_rx *msg,
744 struct drm_dp_sideband_msg_hdr *hdr,
745 u8 hdrlen)
Dave Airliead7f8a12014-06-05 14:01:32 +1000746{
Sean Paul21a729d2020-02-13 16:15:18 -0500747 /*
748 * ignore out-of-order messages or messages that are part of a
749 * failed transaction
750 */
751 if (!hdr->somt && !msg->have_somt)
752 return false;
753
754 /* get length contained in this portion */
755 msg->curchunk_idx = 0;
756 msg->curchunk_len = hdr->msg_len;
757 msg->curchunk_hdrlen = hdrlen;
758
759 /* we have already gotten an somt - don't bother parsing */
760 if (hdr->somt && msg->have_somt)
761 return false;
762
763 if (hdr->somt) {
764 memcpy(&msg->initial_hdr, hdr,
765 sizeof(struct drm_dp_sideband_msg_hdr));
766 msg->have_somt = true;
767 }
768 if (hdr->eomt)
769 msg->have_eomt = true;
770
771 return true;
772}
773
774/* this adds a chunk of msg to the builder to get the final msg */
775static bool drm_dp_sideband_append_payload(struct drm_dp_sideband_msg_rx *msg,
776 u8 *replybuf, u8 replybuflen)
777{
Dave Airliead7f8a12014-06-05 14:01:32 +1000778 u8 crc4;
779
Sean Paul21a729d2020-02-13 16:15:18 -0500780 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
781 msg->curchunk_idx += replybuflen;
Dave Airliead7f8a12014-06-05 14:01:32 +1000782
783 if (msg->curchunk_idx >= msg->curchunk_len) {
784 /* do CRC */
785 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
Benjamin Gaignardd6b8bbc2020-02-03 13:16:20 +0100786 if (crc4 != msg->chunk[msg->curchunk_len - 1])
787 print_hex_dump(KERN_DEBUG, "wrong crc",
788 DUMP_PREFIX_NONE, 16, 1,
789 msg->chunk, msg->curchunk_len, false);
Dave Airliead7f8a12014-06-05 14:01:32 +1000790 /* copy chunk into bigger msg */
791 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
792 msg->curlen += msg->curchunk_len - 1;
793 }
794 return true;
795}
796
Lyude Paul3a08f532021-04-23 14:43:09 -0400797static bool drm_dp_sideband_parse_link_address(const struct drm_dp_mst_topology_mgr *mgr,
798 struct drm_dp_sideband_msg_rx *raw,
Dave Airliead7f8a12014-06-05 14:01:32 +1000799 struct drm_dp_sideband_msg_reply_body *repmsg)
800{
801 int idx = 1;
802 int i;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530803
Dave Airliead7f8a12014-06-05 14:01:32 +1000804 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
805 idx += 16;
806 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
807 idx++;
808 if (idx > raw->curlen)
809 goto fail_len;
810 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
811 if (raw->msg[idx] & 0x80)
812 repmsg->u.link_addr.ports[i].input_port = 1;
813
814 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
815 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
816
817 idx++;
818 if (idx > raw->curlen)
819 goto fail_len;
820 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
821 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
822 if (repmsg->u.link_addr.ports[i].input_port == 0)
823 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
824 idx++;
825 if (idx > raw->curlen)
826 goto fail_len;
827 if (repmsg->u.link_addr.ports[i].input_port == 0) {
828 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
829 idx++;
830 if (idx > raw->curlen)
831 goto fail_len;
832 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
833 idx += 16;
834 if (idx > raw->curlen)
835 goto fail_len;
836 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
837 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
838 idx++;
839
840 }
841 if (idx > raw->curlen)
842 goto fail_len;
843 }
844
845 return true;
846fail_len:
847 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
848 return false;
849}
850
851static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
852 struct drm_dp_sideband_msg_reply_body *repmsg)
853{
854 int idx = 1;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530855
Dave Airliead7f8a12014-06-05 14:01:32 +1000856 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
857 idx++;
858 if (idx > raw->curlen)
859 goto fail_len;
860 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
Hans Verkuila4c30a42018-08-27 10:07:42 +0200861 idx++;
Dave Airliead7f8a12014-06-05 14:01:32 +1000862 if (idx > raw->curlen)
863 goto fail_len;
864
865 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
866 return true;
867fail_len:
868 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
869 return false;
870}
871
872static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
873 struct drm_dp_sideband_msg_reply_body *repmsg)
874{
875 int idx = 1;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530876
Dave Airliead7f8a12014-06-05 14:01:32 +1000877 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
878 idx++;
879 if (idx > raw->curlen)
880 goto fail_len;
881 return true;
882fail_len:
883 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
884 return false;
885}
886
887static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
888 struct drm_dp_sideband_msg_reply_body *repmsg)
889{
890 int idx = 1;
891
892 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
893 idx++;
894 if (idx > raw->curlen)
895 goto fail_len;
896 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
897 idx++;
898 /* TODO check */
899 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
900 return true;
901fail_len:
902 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
903 return false;
904}
905
906static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
907 struct drm_dp_sideband_msg_reply_body *repmsg)
908{
909 int idx = 1;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530910
Dave Airliead7f8a12014-06-05 14:01:32 +1000911 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
David Francisa3c2b0f2019-06-06 11:20:10 -0400912 repmsg->u.path_resources.fec_capable = raw->msg[idx] & 0x1;
Dave Airliead7f8a12014-06-05 14:01:32 +1000913 idx++;
914 if (idx > raw->curlen)
915 goto fail_len;
916 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
917 idx += 2;
918 if (idx > raw->curlen)
919 goto fail_len;
920 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
921 idx += 2;
922 if (idx > raw->curlen)
923 goto fail_len;
924 return true;
925fail_len:
926 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
927 return false;
928}
929
930static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
931 struct drm_dp_sideband_msg_reply_body *repmsg)
932{
933 int idx = 1;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530934
Dave Airliead7f8a12014-06-05 14:01:32 +1000935 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
936 idx++;
937 if (idx > raw->curlen)
938 goto fail_len;
939 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
940 idx++;
941 if (idx > raw->curlen)
942 goto fail_len;
943 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
944 idx += 2;
945 if (idx > raw->curlen)
946 goto fail_len;
947 return true;
948fail_len:
949 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
950 return false;
951}
952
953static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
954 struct drm_dp_sideband_msg_reply_body *repmsg)
955{
956 int idx = 1;
Suraj Upadhyay948de8422020-07-02 18:53:32 +0530957
Dave Airliead7f8a12014-06-05 14:01:32 +1000958 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
959 idx++;
960 if (idx > raw->curlen)
961 goto fail_len;
962 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
963 idx += 2;
964 if (idx > raw->curlen)
965 goto fail_len;
966 return true;
967fail_len:
968 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
969 return false;
970}
971
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -0700972static bool drm_dp_sideband_parse_power_updown_phy_ack(struct drm_dp_sideband_msg_rx *raw,
973 struct drm_dp_sideband_msg_reply_body *repmsg)
974{
975 int idx = 1;
976
977 repmsg->u.port_number.port_number = (raw->msg[idx] >> 4) & 0xf;
978 idx++;
979 if (idx > raw->curlen) {
980 DRM_DEBUG_KMS("power up/down phy parse length fail %d %d\n",
981 idx, raw->curlen);
982 return false;
983 }
984 return true;
985}
986
Sean Paule38c2982020-08-19 10:31:24 -0400987static bool
988drm_dp_sideband_parse_query_stream_enc_status(
989 struct drm_dp_sideband_msg_rx *raw,
990 struct drm_dp_sideband_msg_reply_body *repmsg)
991{
992 struct drm_dp_query_stream_enc_status_ack_reply *reply;
993
994 reply = &repmsg->u.enc_status;
995
996 reply->stream_id = raw->msg[3];
997
998 reply->reply_signed = raw->msg[2] & BIT(0);
999
1000 /*
1001 * NOTE: It's my impression from reading the spec that the below parsing
1002 * is correct. However I noticed while testing with an HDCP 1.4 display
1003 * through an HDCP 2.2 hub that only bit 3 was set. In that case, I
1004 * would expect both bits to be set. So keep the parsing following the
1005 * spec, but beware reality might not match the spec (at least for some
1006 * configurations).
1007 */
1008 reply->hdcp_1x_device_present = raw->msg[2] & BIT(4);
1009 reply->hdcp_2x_device_present = raw->msg[2] & BIT(3);
1010
1011 reply->query_capable_device_present = raw->msg[2] & BIT(5);
1012 reply->legacy_device_present = raw->msg[2] & BIT(6);
1013 reply->unauthorizable_device_present = raw->msg[2] & BIT(7);
1014
1015 reply->auth_completed = !!(raw->msg[1] & BIT(3));
1016 reply->encryption_enabled = !!(raw->msg[1] & BIT(4));
1017 reply->repeater_present = !!(raw->msg[1] & BIT(5));
1018 reply->state = (raw->msg[1] & GENMASK(7, 6)) >> 6;
1019
1020 return true;
1021}
1022
Lyude Paul3a08f532021-04-23 14:43:09 -04001023static bool drm_dp_sideband_parse_reply(const struct drm_dp_mst_topology_mgr *mgr,
1024 struct drm_dp_sideband_msg_rx *raw,
Dave Airliead7f8a12014-06-05 14:01:32 +10001025 struct drm_dp_sideband_msg_reply_body *msg)
1026{
1027 memset(msg, 0, sizeof(*msg));
1028 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
1029 msg->req_type = (raw->msg[0] & 0x7f);
1030
Ville Syrjälä45bbda12019-01-22 22:03:00 +02001031 if (msg->reply_type == DP_SIDEBAND_REPLY_NAK) {
Dave Airliead7f8a12014-06-05 14:01:32 +10001032 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
1033 msg->u.nak.reason = raw->msg[17];
1034 msg->u.nak.nak_data = raw->msg[18];
1035 return false;
1036 }
1037
1038 switch (msg->req_type) {
1039 case DP_LINK_ADDRESS:
Lyude Paul3a08f532021-04-23 14:43:09 -04001040 return drm_dp_sideband_parse_link_address(mgr, raw, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001041 case DP_QUERY_PAYLOAD:
1042 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
1043 case DP_REMOTE_DPCD_READ:
1044 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
1045 case DP_REMOTE_DPCD_WRITE:
1046 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
1047 case DP_REMOTE_I2C_READ:
1048 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
Sam McNallyadb48b22020-07-27 16:03:37 +10001049 case DP_REMOTE_I2C_WRITE:
1050 return true; /* since there's nothing to parse */
Dave Airliead7f8a12014-06-05 14:01:32 +10001051 case DP_ENUM_PATH_RESOURCES:
1052 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
1053 case DP_ALLOCATE_PAYLOAD:
1054 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07001055 case DP_POWER_DOWN_PHY:
1056 case DP_POWER_UP_PHY:
1057 return drm_dp_sideband_parse_power_updown_phy_ack(raw, msg);
Sean Paulf7948902019-08-28 20:09:44 -04001058 case DP_CLEAR_PAYLOAD_ID_TABLE:
1059 return true; /* since there's nothing to parse */
Sean Paule38c2982020-08-19 10:31:24 -04001060 case DP_QUERY_STREAM_ENC_STATUS:
1061 return drm_dp_sideband_parse_query_stream_enc_status(raw, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001062 default:
Lyude Paul3a08f532021-04-23 14:43:09 -04001063 drm_err(mgr->dev, "Got unknown reply 0x%02x (%s)\n",
1064 msg->req_type, drm_dp_mst_req_type_str(msg->req_type));
Dave Airliead7f8a12014-06-05 14:01:32 +10001065 return false;
1066 }
1067}
1068
Lyude Paul3a08f532021-04-23 14:43:09 -04001069static bool
1070drm_dp_sideband_parse_connection_status_notify(const struct drm_dp_mst_topology_mgr *mgr,
1071 struct drm_dp_sideband_msg_rx *raw,
1072 struct drm_dp_sideband_msg_req_body *msg)
Dave Airliead7f8a12014-06-05 14:01:32 +10001073{
1074 int idx = 1;
1075
1076 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
1077 idx++;
1078 if (idx > raw->curlen)
1079 goto fail_len;
1080
1081 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
1082 idx += 16;
1083 if (idx > raw->curlen)
1084 goto fail_len;
1085
1086 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
1087 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
1088 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
1089 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
1090 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
1091 idx++;
1092 return true;
1093fail_len:
Lyude Paul3a08f532021-04-23 14:43:09 -04001094 drm_dbg_kms(mgr->dev, "connection status reply parse length fail %d %d\n",
1095 idx, raw->curlen);
Dave Airliead7f8a12014-06-05 14:01:32 +10001096 return false;
1097}
1098
Lyude Paul3a08f532021-04-23 14:43:09 -04001099static bool drm_dp_sideband_parse_resource_status_notify(const struct drm_dp_mst_topology_mgr *mgr,
1100 struct drm_dp_sideband_msg_rx *raw,
1101 struct drm_dp_sideband_msg_req_body *msg)
Dave Airliead7f8a12014-06-05 14:01:32 +10001102{
1103 int idx = 1;
1104
1105 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
1106 idx++;
1107 if (idx > raw->curlen)
1108 goto fail_len;
1109
1110 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
1111 idx += 16;
1112 if (idx > raw->curlen)
1113 goto fail_len;
1114
1115 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
1116 idx++;
1117 return true;
1118fail_len:
Lyude Paul3a08f532021-04-23 14:43:09 -04001119 drm_dbg_kms(mgr->dev, "resource status reply parse length fail %d %d\n", idx, raw->curlen);
Dave Airliead7f8a12014-06-05 14:01:32 +10001120 return false;
1121}
1122
Lyude Paul3a08f532021-04-23 14:43:09 -04001123static bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr,
1124 struct drm_dp_sideband_msg_rx *raw,
Dave Airliead7f8a12014-06-05 14:01:32 +10001125 struct drm_dp_sideband_msg_req_body *msg)
1126{
1127 memset(msg, 0, sizeof(*msg));
1128 msg->req_type = (raw->msg[0] & 0x7f);
1129
1130 switch (msg->req_type) {
1131 case DP_CONNECTION_STATUS_NOTIFY:
Lyude Paul3a08f532021-04-23 14:43:09 -04001132 return drm_dp_sideband_parse_connection_status_notify(mgr, raw, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001133 case DP_RESOURCE_STATUS_NOTIFY:
Lyude Paul3a08f532021-04-23 14:43:09 -04001134 return drm_dp_sideband_parse_resource_status_notify(mgr, raw, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001135 default:
Lyude Paul3a08f532021-04-23 14:43:09 -04001136 drm_err(mgr->dev, "Got unknown request 0x%02x (%s)\n",
1137 msg->req_type, drm_dp_mst_req_type_str(msg->req_type));
Dave Airliead7f8a12014-06-05 14:01:32 +10001138 return false;
1139 }
1140}
1141
Benjamin Gaignardcb897542020-02-05 09:48:42 +01001142static void build_dpcd_write(struct drm_dp_sideband_msg_tx *msg,
1143 u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
Dave Airliead7f8a12014-06-05 14:01:32 +10001144{
1145 struct drm_dp_sideband_msg_req_body req;
1146
1147 req.req_type = DP_REMOTE_DPCD_WRITE;
1148 req.u.dpcd_write.port_number = port_num;
1149 req.u.dpcd_write.dpcd_address = offset;
1150 req.u.dpcd_write.num_bytes = num_bytes;
1151 req.u.dpcd_write.bytes = bytes;
1152 drm_dp_encode_sideband_req(&req, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001153}
1154
Benjamin Gaignardcb897542020-02-05 09:48:42 +01001155static void build_link_address(struct drm_dp_sideband_msg_tx *msg)
Dave Airliead7f8a12014-06-05 14:01:32 +10001156{
1157 struct drm_dp_sideband_msg_req_body req;
1158
1159 req.req_type = DP_LINK_ADDRESS;
1160 drm_dp_encode_sideband_req(&req, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10001161}
1162
Maya Rashishbdf7e3b2020-03-21 22:29:59 +00001163static void build_clear_payload_id_table(struct drm_dp_sideband_msg_tx *msg)
Sean Paulf7948902019-08-28 20:09:44 -04001164{
1165 struct drm_dp_sideband_msg_req_body req;
1166
1167 req.req_type = DP_CLEAR_PAYLOAD_ID_TABLE;
1168 drm_dp_encode_sideband_req(&req, msg);
Wayne Lind919d3d2021-02-24 18:15:21 +08001169 msg->path_msg = true;
Sean Paulf7948902019-08-28 20:09:44 -04001170}
1171
Benjamin Gaignardcb897542020-02-05 09:48:42 +01001172static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg,
1173 int port_num)
Dave Airliead7f8a12014-06-05 14:01:32 +10001174{
1175 struct drm_dp_sideband_msg_req_body req;
1176
1177 req.req_type = DP_ENUM_PATH_RESOURCES;
1178 req.u.port_num.port_number = port_num;
1179 drm_dp_encode_sideband_req(&req, msg);
1180 msg->path_msg = true;
1181 return 0;
1182}
1183
Benjamin Gaignardcb897542020-02-05 09:48:42 +01001184static void build_allocate_payload(struct drm_dp_sideband_msg_tx *msg,
1185 int port_num,
1186 u8 vcpi, uint16_t pbn,
1187 u8 number_sdp_streams,
1188 u8 *sdp_stream_sink)
Dave Airliead7f8a12014-06-05 14:01:32 +10001189{
1190 struct drm_dp_sideband_msg_req_body req;
Suraj Upadhyay948de8422020-07-02 18:53:32 +05301191
Dave Airliead7f8a12014-06-05 14:01:32 +10001192 memset(&req, 0, sizeof(req));
1193 req.req_type = DP_ALLOCATE_PAYLOAD;
1194 req.u.allocate_payload.port_number = port_num;
1195 req.u.allocate_payload.vcpi = vcpi;
1196 req.u.allocate_payload.pbn = pbn;
Libin Yangef8f9be2015-12-02 14:09:43 +08001197 req.u.allocate_payload.number_sdp_streams = number_sdp_streams;
1198 memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink,
1199 number_sdp_streams);
Dave Airliead7f8a12014-06-05 14:01:32 +10001200 drm_dp_encode_sideband_req(&req, msg);
1201 msg->path_msg = true;
Dave Airliead7f8a12014-06-05 14:01:32 +10001202}
1203
Benjamin Gaignardcb897542020-02-05 09:48:42 +01001204static void build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
1205 int port_num, bool power_up)
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07001206{
1207 struct drm_dp_sideband_msg_req_body req;
1208
1209 if (power_up)
1210 req.req_type = DP_POWER_UP_PHY;
1211 else
1212 req.req_type = DP_POWER_DOWN_PHY;
1213
1214 req.u.port_num.port_number = port_num;
1215 drm_dp_encode_sideband_req(&req, msg);
1216 msg->path_msg = true;
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07001217}
1218
Sean Paule38c2982020-08-19 10:31:24 -04001219static int
1220build_query_stream_enc_status(struct drm_dp_sideband_msg_tx *msg, u8 stream_id,
1221 u8 *q_id)
1222{
1223 struct drm_dp_sideband_msg_req_body req;
1224
1225 req.req_type = DP_QUERY_STREAM_ENC_STATUS;
1226 req.u.enc_status.stream_id = stream_id;
1227 memcpy(req.u.enc_status.client_id, q_id,
1228 sizeof(req.u.enc_status.client_id));
1229 req.u.enc_status.stream_event = 0;
1230 req.u.enc_status.valid_stream_event = false;
1231 req.u.enc_status.stream_behavior = 0;
1232 req.u.enc_status.valid_stream_behavior = false;
1233
1234 drm_dp_encode_sideband_req(&req, msg);
1235 return 0;
1236}
1237
Dave Airliead7f8a12014-06-05 14:01:32 +10001238static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
1239 struct drm_dp_sideband_msg_tx *txmsg)
1240{
Chris Wilson992d38c2017-05-13 11:52:00 +01001241 unsigned int state;
Daniel Vettercd961bb2015-01-28 10:02:23 +01001242
1243 /*
1244 * All updates to txmsg->state are protected by mgr->qlock, and the two
1245 * cases we check here are terminal states. For those the barriers
1246 * provided by the wake_up/wait_event pair are enough.
1247 */
Chris Wilson992d38c2017-05-13 11:52:00 +01001248 state = READ_ONCE(txmsg->state);
1249 return (state == DRM_DP_SIDEBAND_TX_RX ||
1250 state == DRM_DP_SIDEBAND_TX_TIMEOUT);
Dave Airliead7f8a12014-06-05 14:01:32 +10001251}
1252
1253static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
1254 struct drm_dp_sideband_msg_tx *txmsg)
1255{
1256 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
Imre Deak471bdd02020-06-04 21:45:00 +03001257 unsigned long wait_timeout = msecs_to_jiffies(4000);
1258 unsigned long wait_expires = jiffies + wait_timeout;
Dave Airliead7f8a12014-06-05 14:01:32 +10001259 int ret;
1260
Imre Deak471bdd02020-06-04 21:45:00 +03001261 for (;;) {
1262 /*
1263 * If the driver provides a way for this, change to
1264 * poll-waiting for the MST reply interrupt if we didn't receive
1265 * it for 50 msec. This would cater for cases where the HPD
1266 * pulse signal got lost somewhere, even though the sink raised
1267 * the corresponding MST interrupt correctly. One example is the
1268 * Club 3D CAC-1557 TypeC -> DP adapter which for some reason
1269 * filters out short pulses with a duration less than ~540 usec.
1270 *
1271 * The poll period is 50 msec to avoid missing an interrupt
1272 * after the sink has cleared it (after a 110msec timeout
1273 * since it raised the interrupt).
1274 */
1275 ret = wait_event_timeout(mgr->tx_waitq,
1276 check_txmsg_state(mgr, txmsg),
1277 mgr->cbs->poll_hpd_irq ?
1278 msecs_to_jiffies(50) :
1279 wait_timeout);
1280
1281 if (ret || !mgr->cbs->poll_hpd_irq ||
1282 time_after(jiffies, wait_expires))
1283 break;
1284
1285 mgr->cbs->poll_hpd_irq(mgr);
1286 }
1287
Imre Deak8b9f3432020-06-04 00:10:39 +03001288 mutex_lock(&mgr->qlock);
Dave Airliead7f8a12014-06-05 14:01:32 +10001289 if (ret > 0) {
1290 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
1291 ret = -EIO;
1292 goto out;
1293 }
1294 } else {
Lyude Paul3a08f532021-04-23 14:43:09 -04001295 drm_dbg_kms(mgr->dev, "timedout msg send %p %d %d\n",
1296 txmsg, txmsg->state, txmsg->seqno);
Dave Airliead7f8a12014-06-05 14:01:32 +10001297
1298 /* dump some state */
1299 ret = -EIO;
1300
1301 /* remove from q */
1302 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
Imre Deak58c17212020-05-13 13:31:55 +03001303 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
1304 txmsg->state == DRM_DP_SIDEBAND_TX_SENT)
Dave Airliead7f8a12014-06-05 14:01:32 +10001305 list_del(&txmsg->next);
Dave Airliead7f8a12014-06-05 14:01:32 +10001306 }
1307out:
Jani Nikulaf0a8f532019-10-01 17:06:14 +03001308 if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) {
Jani Nikula6470aac2024-01-16 15:07:29 +02001309 struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP,
1310 DBG_PREFIX);
Lyude Paul2f015ec2019-09-03 16:45:45 -04001311
1312 drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
1313 }
Dave Airliead7f8a12014-06-05 14:01:32 +10001314 mutex_unlock(&mgr->qlock);
1315
Wayne Lin5a649672020-01-13 17:36:49 +08001316 drm_dp_mst_kick_tx(mgr);
Dave Airliead7f8a12014-06-05 14:01:32 +10001317 return ret;
1318}
1319
1320static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
1321{
1322 struct drm_dp_mst_branch *mstb;
1323
1324 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
1325 if (!mstb)
1326 return NULL;
1327
1328 mstb->lct = lct;
1329 if (lct > 1)
1330 memcpy(mstb->rad, rad, lct / 2);
1331 INIT_LIST_HEAD(&mstb->ports);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001332 kref_init(&mstb->topology_kref);
1333 kref_init(&mstb->malloc_kref);
Dave Airliead7f8a12014-06-05 14:01:32 +10001334 return mstb;
1335}
1336
Mykola Lysenko91a25e42016-01-27 09:39:36 -05001337static void drm_dp_free_mst_branch_device(struct kref *kref)
1338{
Lyude Paulebcc0e62019-01-10 19:53:29 -05001339 struct drm_dp_mst_branch *mstb =
1340 container_of(kref, struct drm_dp_mst_branch, malloc_kref);
1341
1342 if (mstb->port_parent)
1343 drm_dp_mst_put_port_malloc(mstb->port_parent);
1344
Mykola Lysenko91a25e42016-01-27 09:39:36 -05001345 kfree(mstb);
1346}
1347
Lyude Paulebcc0e62019-01-10 19:53:29 -05001348/**
1349 * DOC: Branch device and port refcounting
1350 *
1351 * Topology refcount overview
1352 * ~~~~~~~~~~~~~~~~~~~~~~~~~~
1353 *
1354 * The refcounting schemes for &struct drm_dp_mst_branch and &struct
1355 * drm_dp_mst_port are somewhat unusual. Both ports and branch devices have
1356 * two different kinds of refcounts: topology refcounts, and malloc refcounts.
1357 *
1358 * Topology refcounts are not exposed to drivers, and are handled internally
1359 * by the DP MST helpers. The helpers use them in order to prevent the
1360 * in-memory topology state from being changed in the middle of critical
1361 * operations like changing the internal state of payload allocations. This
1362 * means each branch and port will be considered to be connected to the rest
Matt Roper1e55a532019-02-01 17:23:26 -08001363 * of the topology until its topology refcount reaches zero. Additionally,
Lyude Paulebcc0e62019-01-10 19:53:29 -05001364 * for ports this means that their associated &struct drm_connector will stay
1365 * registered with userspace until the port's refcount reaches 0.
1366 *
1367 * Malloc refcount overview
1368 * ~~~~~~~~~~~~~~~~~~~~~~~~
1369 *
1370 * Malloc references are used to keep a &struct drm_dp_mst_port or &struct
1371 * drm_dp_mst_branch allocated even after all of its topology references have
1372 * been dropped, so that the driver or MST helpers can safely access each
1373 * branch's last known state before it was disconnected from the topology.
1374 * When the malloc refcount of a port or branch reaches 0, the memory
1375 * allocation containing the &struct drm_dp_mst_branch or &struct
1376 * drm_dp_mst_port respectively will be freed.
1377 *
1378 * For &struct drm_dp_mst_branch, malloc refcounts are not currently exposed
1379 * to drivers. As of writing this documentation, there are no drivers that
1380 * have a usecase for accessing &struct drm_dp_mst_branch outside of the MST
1381 * helpers. Exposing this API to drivers in a race-free manner would take more
1382 * tweaking of the refcounting scheme, however patches are welcome provided
1383 * there is a legitimate driver usecase for this.
1384 *
1385 * Refcount relationships in a topology
1386 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1387 *
1388 * Let's take a look at why the relationship between topology and malloc
1389 * refcounts is designed the way it is.
1390 *
1391 * .. kernel-figure:: dp-mst/topology-figure-1.dot
1392 *
1393 * An example of topology and malloc refs in a DP MST topology with two
1394 * active payloads. Topology refcount increments are indicated by solid
1395 * lines, and malloc refcount increments are indicated by dashed lines.
1396 * Each starts from the branch which incremented the refcount, and ends at
1397 * the branch to which the refcount belongs to, i.e. the arrow points the
1398 * same way as the C pointers used to reference a structure.
1399 *
1400 * As you can see in the above figure, every branch increments the topology
Matt Roper1e55a532019-02-01 17:23:26 -08001401 * refcount of its children, and increments the malloc refcount of its
1402 * parent. Additionally, every payload increments the malloc refcount of its
Lyude Paulebcc0e62019-01-10 19:53:29 -05001403 * assigned port by 1.
1404 *
1405 * So, what would happen if MSTB #3 from the above figure was unplugged from
1406 * the system, but the driver hadn't yet removed payload #2 from port #3? The
1407 * topology would start to look like the figure below.
1408 *
1409 * .. kernel-figure:: dp-mst/topology-figure-2.dot
1410 *
1411 * Ports and branch devices which have been released from memory are
1412 * colored grey, and references which have been removed are colored red.
1413 *
1414 * Whenever a port or branch device's topology refcount reaches zero, it will
1415 * decrement the topology refcounts of all its children, the malloc refcount
1416 * of its parent, and finally its own malloc refcount. For MSTB #4 and port
1417 * #4, this means they both have been disconnected from the topology and freed
1418 * from memory. But, because payload #2 is still holding a reference to port
Matt Roper1e55a532019-02-01 17:23:26 -08001419 * #3, port #3 is removed from the topology but its &struct drm_dp_mst_port
Lyude Paulebcc0e62019-01-10 19:53:29 -05001420 * is still accessible from memory. This also means port #3 has not yet
Matt Roper1e55a532019-02-01 17:23:26 -08001421 * decremented the malloc refcount of MSTB #3, so its &struct
Lyude Paulebcc0e62019-01-10 19:53:29 -05001422 * drm_dp_mst_branch will also stay allocated in memory until port #3's
1423 * malloc refcount reaches 0.
1424 *
1425 * This relationship is necessary because in order to release payload #2, we
1426 * need to be able to figure out the last relative of port #3 that's still
1427 * connected to the topology. In this case, we would travel up the topology as
1428 * shown below.
1429 *
1430 * .. kernel-figure:: dp-mst/topology-figure-3.dot
1431 *
1432 * And finally, remove payload #2 by communicating with port #2 through
1433 * sideband transactions.
1434 */
1435
1436/**
1437 * drm_dp_mst_get_mstb_malloc() - Increment the malloc refcount of a branch
1438 * device
1439 * @mstb: The &struct drm_dp_mst_branch to increment the malloc refcount of
1440 *
1441 * Increments &drm_dp_mst_branch.malloc_kref. When
1442 * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb
1443 * will be released and @mstb may no longer be used.
1444 *
1445 * See also: drm_dp_mst_put_mstb_malloc()
1446 */
1447static void
1448drm_dp_mst_get_mstb_malloc(struct drm_dp_mst_branch *mstb)
1449{
1450 kref_get(&mstb->malloc_kref);
Lyude Paul3a08f532021-04-23 14:43:09 -04001451 drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref));
Lyude Paulebcc0e62019-01-10 19:53:29 -05001452}
1453
1454/**
1455 * drm_dp_mst_put_mstb_malloc() - Decrement the malloc refcount of a branch
1456 * device
1457 * @mstb: The &struct drm_dp_mst_branch to decrement the malloc refcount of
1458 *
1459 * Decrements &drm_dp_mst_branch.malloc_kref. When
1460 * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb
1461 * will be released and @mstb may no longer be used.
1462 *
1463 * See also: drm_dp_mst_get_mstb_malloc()
1464 */
1465static void
1466drm_dp_mst_put_mstb_malloc(struct drm_dp_mst_branch *mstb)
1467{
Lyude Paul3a08f532021-04-23 14:43:09 -04001468 drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref) - 1);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001469 kref_put(&mstb->malloc_kref, drm_dp_free_mst_branch_device);
1470}
1471
1472static void drm_dp_free_mst_port(struct kref *kref)
1473{
1474 struct drm_dp_mst_port *port =
1475 container_of(kref, struct drm_dp_mst_port, malloc_kref);
1476
1477 drm_dp_mst_put_mstb_malloc(port->parent);
1478 kfree(port);
1479}
1480
1481/**
1482 * drm_dp_mst_get_port_malloc() - Increment the malloc refcount of an MST port
1483 * @port: The &struct drm_dp_mst_port to increment the malloc refcount of
1484 *
1485 * Increments &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref
1486 * reaches 0, the memory allocation for @port will be released and @port may
1487 * no longer be used.
1488 *
1489 * Because @port could potentially be freed at any time by the DP MST helpers
1490 * if &drm_dp_mst_port.malloc_kref reaches 0, including during a call to this
1491 * function, drivers that which to make use of &struct drm_dp_mst_port should
1492 * ensure that they grab at least one main malloc reference to their MST ports
1493 * in &drm_dp_mst_topology_cbs.add_connector. This callback is called before
1494 * there is any chance for &drm_dp_mst_port.malloc_kref to reach 0.
1495 *
1496 * See also: drm_dp_mst_put_port_malloc()
1497 */
1498void
1499drm_dp_mst_get_port_malloc(struct drm_dp_mst_port *port)
1500{
1501 kref_get(&port->malloc_kref);
Lyude Paul3a08f532021-04-23 14:43:09 -04001502 drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref));
Lyude Paulebcc0e62019-01-10 19:53:29 -05001503}
1504EXPORT_SYMBOL(drm_dp_mst_get_port_malloc);
1505
1506/**
1507 * drm_dp_mst_put_port_malloc() - Decrement the malloc refcount of an MST port
1508 * @port: The &struct drm_dp_mst_port to decrement the malloc refcount of
1509 *
1510 * Decrements &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref
1511 * reaches 0, the memory allocation for @port will be released and @port may
1512 * no longer be used.
1513 *
1514 * See also: drm_dp_mst_get_port_malloc()
1515 */
1516void
1517drm_dp_mst_put_port_malloc(struct drm_dp_mst_port *port)
1518{
Lyude Paul3a08f532021-04-23 14:43:09 -04001519 drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref) - 1);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001520 kref_put(&port->malloc_kref, drm_dp_free_mst_port);
1521}
1522EXPORT_SYMBOL(drm_dp_mst_put_port_malloc);
1523
Lyude Paul12a280c2019-06-20 17:59:25 -04001524#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
1525
1526#define STACK_DEPTH 8
1527
1528static noinline void
1529__topology_ref_save(struct drm_dp_mst_topology_mgr *mgr,
1530 struct drm_dp_mst_topology_ref_history *history,
1531 enum drm_dp_mst_topology_ref_type type)
1532{
1533 struct drm_dp_mst_topology_ref_entry *entry = NULL;
1534 depot_stack_handle_t backtrace;
1535 ulong stack_entries[STACK_DEPTH];
1536 uint n;
1537 int i;
1538
1539 n = stack_trace_save(stack_entries, ARRAY_SIZE(stack_entries), 1);
1540 backtrace = stack_depot_save(stack_entries, n, GFP_KERNEL);
1541 if (!backtrace)
1542 return;
1543
1544 /* Try to find an existing entry for this backtrace */
1545 for (i = 0; i < history->len; i++) {
1546 if (history->entries[i].backtrace == backtrace) {
1547 entry = &history->entries[i];
1548 break;
1549 }
1550 }
1551
1552 /* Otherwise add one */
1553 if (!entry) {
1554 struct drm_dp_mst_topology_ref_entry *new;
1555 int new_len = history->len + 1;
1556
1557 new = krealloc(history->entries, sizeof(*new) * new_len,
1558 GFP_KERNEL);
1559 if (!new)
1560 return;
1561
1562 entry = &new[history->len];
1563 history->len = new_len;
1564 history->entries = new;
1565
1566 entry->backtrace = backtrace;
1567 entry->type = type;
1568 entry->count = 0;
1569 }
1570 entry->count++;
1571 entry->ts_nsec = ktime_get_ns();
1572}
1573
1574static int
1575topology_ref_history_cmp(const void *a, const void *b)
1576{
1577 const struct drm_dp_mst_topology_ref_entry *entry_a = a, *entry_b = b;
1578
1579 if (entry_a->ts_nsec > entry_b->ts_nsec)
1580 return 1;
1581 else if (entry_a->ts_nsec < entry_b->ts_nsec)
1582 return -1;
1583 else
1584 return 0;
1585}
1586
1587static inline const char *
1588topology_ref_type_to_str(enum drm_dp_mst_topology_ref_type type)
1589{
1590 if (type == DRM_DP_MST_TOPOLOGY_REF_GET)
1591 return "get";
1592 else
1593 return "put";
1594}
1595
1596static void
Jani Nikula6470aac2024-01-16 15:07:29 +02001597__dump_topology_ref_history(struct drm_device *drm,
1598 struct drm_dp_mst_topology_ref_history *history,
Lyude Paul12a280c2019-06-20 17:59:25 -04001599 void *ptr, const char *type_str)
1600{
Jani Nikula6470aac2024-01-16 15:07:29 +02001601 struct drm_printer p = drm_dbg_printer(drm, DRM_UT_DP, DBG_PREFIX);
Lyude Paul12a280c2019-06-20 17:59:25 -04001602 char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
1603 int i;
1604
1605 if (!buf)
1606 return;
1607
1608 if (!history->len)
1609 goto out;
1610
1611 /* First, sort the list so that it goes from oldest to newest
1612 * reference entry
1613 */
1614 sort(history->entries, history->len, sizeof(*history->entries),
1615 topology_ref_history_cmp, NULL);
1616
1617 drm_printf(&p, "%s (%p) topology count reached 0, dumping history:\n",
1618 type_str, ptr);
1619
1620 for (i = 0; i < history->len; i++) {
1621 const struct drm_dp_mst_topology_ref_entry *entry =
1622 &history->entries[i];
Lyude Paul12a280c2019-06-20 17:59:25 -04001623 u64 ts_nsec = entry->ts_nsec;
Sean Paulb149cbf2019-11-06 14:41:15 -05001624 u32 rem_nsec = do_div(ts_nsec, 1000000000);
Lyude Paul12a280c2019-06-20 17:59:25 -04001625
Imran Khan0f68d452021-11-08 18:33:16 -08001626 stack_depot_snprint(entry->backtrace, buf, PAGE_SIZE, 4);
Lyude Paul12a280c2019-06-20 17:59:25 -04001627
Sean Paulb149cbf2019-11-06 14:41:15 -05001628 drm_printf(&p, " %d %ss (last at %5llu.%06u):\n%s",
Lyude Paul12a280c2019-06-20 17:59:25 -04001629 entry->count,
1630 topology_ref_type_to_str(entry->type),
1631 ts_nsec, rem_nsec / 1000, buf);
1632 }
1633
1634 /* Now free the history, since this is the only time we expose it */
1635 kfree(history->entries);
1636out:
1637 kfree(buf);
1638}
1639
1640static __always_inline void
1641drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb)
1642{
Jani Nikula6470aac2024-01-16 15:07:29 +02001643 __dump_topology_ref_history(mstb->mgr->dev, &mstb->topology_ref_history,
1644 mstb, "MSTB");
Lyude Paul12a280c2019-06-20 17:59:25 -04001645}
1646
1647static __always_inline void
1648drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port)
1649{
Jani Nikula6470aac2024-01-16 15:07:29 +02001650 __dump_topology_ref_history(port->mgr->dev, &port->topology_ref_history,
1651 port, "Port");
Lyude Paul12a280c2019-06-20 17:59:25 -04001652}
1653
1654static __always_inline void
1655save_mstb_topology_ref(struct drm_dp_mst_branch *mstb,
1656 enum drm_dp_mst_topology_ref_type type)
1657{
1658 __topology_ref_save(mstb->mgr, &mstb->topology_ref_history, type);
1659}
1660
1661static __always_inline void
1662save_port_topology_ref(struct drm_dp_mst_port *port,
1663 enum drm_dp_mst_topology_ref_type type)
1664{
1665 __topology_ref_save(port->mgr, &port->topology_ref_history, type);
1666}
1667
1668static inline void
1669topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr)
1670{
1671 mutex_lock(&mgr->topology_ref_history_lock);
1672}
1673
1674static inline void
1675topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr)
1676{
1677 mutex_unlock(&mgr->topology_ref_history_lock);
1678}
1679#else
1680static inline void
1681topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr) {}
1682static inline void
1683topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr) {}
1684static inline void
1685drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) {}
1686static inline void
1687drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) {}
1688#define save_mstb_topology_ref(mstb, type)
1689#define save_port_topology_ref(port, type)
1690#endif
1691
Lyude Paul4d07b0b2022-08-17 15:38:46 -04001692struct drm_dp_mst_atomic_payload *
Lyude Paul0b4e4772022-08-17 15:38:36 -04001693drm_atomic_get_mst_payload_state(struct drm_dp_mst_topology_state *state,
1694 struct drm_dp_mst_port *port)
1695{
1696 struct drm_dp_mst_atomic_payload *payload;
1697
1698 list_for_each_entry(payload, &state->payloads, next)
1699 if (payload->port == port)
1700 return payload;
1701
1702 return NULL;
1703}
Lyude Paul4d07b0b2022-08-17 15:38:46 -04001704EXPORT_SYMBOL(drm_atomic_get_mst_payload_state);
Lyude Paul0b4e4772022-08-17 15:38:36 -04001705
Dave Airliead7f8a12014-06-05 14:01:32 +10001706static void drm_dp_destroy_mst_branch_device(struct kref *kref)
1707{
Lyude Paulebcc0e62019-01-10 19:53:29 -05001708 struct drm_dp_mst_branch *mstb =
1709 container_of(kref, struct drm_dp_mst_branch, topology_kref);
1710 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
Dave Airliead7f8a12014-06-05 14:01:32 +10001711
Lyude Paul12a280c2019-06-20 17:59:25 -04001712 drm_dp_mst_dump_mstb_topology_history(mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10001713
Lyude Paul7cb12d42019-02-19 17:41:02 -05001714 INIT_LIST_HEAD(&mstb->destroy_next);
Dave Airliead7f8a12014-06-05 14:01:32 +10001715
Lyude Paul7cb12d42019-02-19 17:41:02 -05001716 /*
1717 * This can get called under mgr->mutex, so we need to perform the
1718 * actual destruction of the mstb in another worker
1719 */
1720 mutex_lock(&mgr->delayed_destroy_lock);
1721 list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list);
1722 mutex_unlock(&mgr->delayed_destroy_lock);
Imre Deak72822c32020-06-10 16:47:04 +03001723 queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work);
Dave Airliead7f8a12014-06-05 14:01:32 +10001724}
1725
Lyude Paulebcc0e62019-01-10 19:53:29 -05001726/**
1727 * drm_dp_mst_topology_try_get_mstb() - Increment the topology refcount of a
Matt Roper1e55a532019-02-01 17:23:26 -08001728 * branch device unless it's zero
Lyude Paulebcc0e62019-01-10 19:53:29 -05001729 * @mstb: &struct drm_dp_mst_branch to increment the topology refcount of
1730 *
1731 * Attempts to grab a topology reference to @mstb, if it hasn't yet been
1732 * removed from the topology (e.g. &drm_dp_mst_branch.topology_kref has
1733 * reached 0). Holding a topology reference implies that a malloc reference
1734 * will be held to @mstb as long as the user holds the topology reference.
1735 *
1736 * Care should be taken to ensure that the user has at least one malloc
1737 * reference to @mstb. If you already have a topology reference to @mstb, you
1738 * should use drm_dp_mst_topology_get_mstb() instead.
1739 *
1740 * See also:
1741 * drm_dp_mst_topology_get_mstb()
1742 * drm_dp_mst_topology_put_mstb()
1743 *
1744 * Returns:
1745 * * 1: A topology reference was grabbed successfully
1746 * * 0: @port is no longer in the topology, no reference was grabbed
1747 */
1748static int __must_check
1749drm_dp_mst_topology_try_get_mstb(struct drm_dp_mst_branch *mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10001750{
Lyude Paul12a280c2019-06-20 17:59:25 -04001751 int ret;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001752
Lyude Paul12a280c2019-06-20 17:59:25 -04001753 topology_ref_history_lock(mstb->mgr);
1754 ret = kref_get_unless_zero(&mstb->topology_kref);
1755 if (ret) {
Lyude Paul3a08f532021-04-23 14:43:09 -04001756 drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref));
Lyude Paul12a280c2019-06-20 17:59:25 -04001757 save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET);
1758 }
1759
1760 topology_ref_history_unlock(mstb->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001761
1762 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10001763}
1764
Lyude Paulebcc0e62019-01-10 19:53:29 -05001765/**
1766 * drm_dp_mst_topology_get_mstb() - Increment the topology refcount of a
1767 * branch device
1768 * @mstb: The &struct drm_dp_mst_branch to increment the topology refcount of
1769 *
1770 * Increments &drm_dp_mst_branch.topology_refcount without checking whether or
1771 * not it's already reached 0. This is only valid to use in scenarios where
1772 * you are already guaranteed to have at least one active topology reference
1773 * to @mstb. Otherwise, drm_dp_mst_topology_try_get_mstb() must be used.
1774 *
1775 * See also:
1776 * drm_dp_mst_topology_try_get_mstb()
1777 * drm_dp_mst_topology_put_mstb()
1778 */
1779static void drm_dp_mst_topology_get_mstb(struct drm_dp_mst_branch *mstb)
1780{
Lyude Paul12a280c2019-06-20 17:59:25 -04001781 topology_ref_history_lock(mstb->mgr);
1782
1783 save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001784 WARN_ON(kref_read(&mstb->topology_kref) == 0);
1785 kref_get(&mstb->topology_kref);
Lyude Paul3a08f532021-04-23 14:43:09 -04001786 drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref));
Lyude Paul12a280c2019-06-20 17:59:25 -04001787
1788 topology_ref_history_unlock(mstb->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001789}
1790
1791/**
1792 * drm_dp_mst_topology_put_mstb() - release a topology reference to a branch
1793 * device
1794 * @mstb: The &struct drm_dp_mst_branch to release the topology reference from
1795 *
1796 * Releases a topology reference from @mstb by decrementing
1797 * &drm_dp_mst_branch.topology_kref.
1798 *
1799 * See also:
1800 * drm_dp_mst_topology_try_get_mstb()
1801 * drm_dp_mst_topology_get_mstb()
1802 */
1803static void
1804drm_dp_mst_topology_put_mstb(struct drm_dp_mst_branch *mstb)
1805{
Lyude Paul12a280c2019-06-20 17:59:25 -04001806 topology_ref_history_lock(mstb->mgr);
1807
Lyude Paul3a08f532021-04-23 14:43:09 -04001808 drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref) - 1);
Lyude Paul12a280c2019-06-20 17:59:25 -04001809 save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_PUT);
1810
1811 topology_ref_history_unlock(mstb->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001812 kref_put(&mstb->topology_kref, drm_dp_destroy_mst_branch_device);
1813}
Dave Airliead7f8a12014-06-05 14:01:32 +10001814
Dave Airliead7f8a12014-06-05 14:01:32 +10001815static void drm_dp_destroy_port(struct kref *kref)
1816{
Lyude Paulebcc0e62019-01-10 19:53:29 -05001817 struct drm_dp_mst_port *port =
1818 container_of(kref, struct drm_dp_mst_port, topology_kref);
Dave Airliead7f8a12014-06-05 14:01:32 +10001819 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
Dave Airliedf4839f2015-09-16 10:37:28 +10001820
Lyude Paul12a280c2019-06-20 17:59:25 -04001821 drm_dp_mst_dump_port_topology_history(port);
Dave Airlie6b8eeca2015-06-15 10:34:28 +10001822
Lyude Pauld29333c2019-03-10 18:59:10 -04001823 /* There's nothing that needs locking to destroy an input port yet */
1824 if (port->input) {
1825 drm_dp_mst_put_port_malloc(port);
1826 return;
Dave Airliead7f8a12014-06-05 14:01:32 +10001827 }
Lyude Pauld29333c2019-03-10 18:59:10 -04001828
Jani Nikulac1c90422023-05-30 12:08:24 +03001829 drm_edid_free(port->cached_edid);
Lyude Pauld29333c2019-03-10 18:59:10 -04001830
1831 /*
1832 * we can't destroy the connector here, as we might be holding the
1833 * mode_config.mutex from an EDID retrieval
1834 */
1835 mutex_lock(&mgr->delayed_destroy_lock);
1836 list_add(&port->next, &mgr->destroy_port_list);
1837 mutex_unlock(&mgr->delayed_destroy_lock);
Imre Deak72822c32020-06-10 16:47:04 +03001838 queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work);
Dave Airliead7f8a12014-06-05 14:01:32 +10001839}
1840
Lyude Paulebcc0e62019-01-10 19:53:29 -05001841/**
1842 * drm_dp_mst_topology_try_get_port() - Increment the topology refcount of a
Matt Roper1e55a532019-02-01 17:23:26 -08001843 * port unless it's zero
Lyude Paulebcc0e62019-01-10 19:53:29 -05001844 * @port: &struct drm_dp_mst_port to increment the topology refcount of
1845 *
1846 * Attempts to grab a topology reference to @port, if it hasn't yet been
1847 * removed from the topology (e.g. &drm_dp_mst_port.topology_kref has reached
1848 * 0). Holding a topology reference implies that a malloc reference will be
1849 * held to @port as long as the user holds the topology reference.
1850 *
1851 * Care should be taken to ensure that the user has at least one malloc
1852 * reference to @port. If you already have a topology reference to @port, you
1853 * should use drm_dp_mst_topology_get_port() instead.
1854 *
1855 * See also:
1856 * drm_dp_mst_topology_get_port()
1857 * drm_dp_mst_topology_put_port()
1858 *
1859 * Returns:
1860 * * 1: A topology reference was grabbed successfully
1861 * * 0: @port is no longer in the topology, no reference was grabbed
1862 */
1863static int __must_check
1864drm_dp_mst_topology_try_get_port(struct drm_dp_mst_port *port)
1865{
Lyude Paul12a280c2019-06-20 17:59:25 -04001866 int ret;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001867
Lyude Paul12a280c2019-06-20 17:59:25 -04001868 topology_ref_history_lock(port->mgr);
1869 ret = kref_get_unless_zero(&port->topology_kref);
1870 if (ret) {
Lyude Paul3a08f532021-04-23 14:43:09 -04001871 drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref));
Lyude Paul12a280c2019-06-20 17:59:25 -04001872 save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET);
1873 }
Lyude Paulebcc0e62019-01-10 19:53:29 -05001874
Lyude Paul12a280c2019-06-20 17:59:25 -04001875 topology_ref_history_unlock(port->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001876 return ret;
1877}
1878
1879/**
1880 * drm_dp_mst_topology_get_port() - Increment the topology refcount of a port
1881 * @port: The &struct drm_dp_mst_port to increment the topology refcount of
1882 *
1883 * Increments &drm_dp_mst_port.topology_refcount without checking whether or
1884 * not it's already reached 0. This is only valid to use in scenarios where
1885 * you are already guaranteed to have at least one active topology reference
1886 * to @port. Otherwise, drm_dp_mst_topology_try_get_port() must be used.
1887 *
1888 * See also:
1889 * drm_dp_mst_topology_try_get_port()
1890 * drm_dp_mst_topology_put_port()
1891 */
1892static void drm_dp_mst_topology_get_port(struct drm_dp_mst_port *port)
1893{
Lyude Paul12a280c2019-06-20 17:59:25 -04001894 topology_ref_history_lock(port->mgr);
1895
Lyude Paulebcc0e62019-01-10 19:53:29 -05001896 WARN_ON(kref_read(&port->topology_kref) == 0);
1897 kref_get(&port->topology_kref);
Lyude Paul3a08f532021-04-23 14:43:09 -04001898 drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref));
Lyude Paul12a280c2019-06-20 17:59:25 -04001899 save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET);
1900
1901 topology_ref_history_unlock(port->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001902}
1903
1904/**
1905 * drm_dp_mst_topology_put_port() - release a topology reference to a port
1906 * @port: The &struct drm_dp_mst_port to release the topology reference from
1907 *
1908 * Releases a topology reference from @port by decrementing
1909 * &drm_dp_mst_port.topology_kref.
1910 *
1911 * See also:
1912 * drm_dp_mst_topology_try_get_port()
1913 * drm_dp_mst_topology_get_port()
1914 */
Lyude Pauld0757af2019-01-10 19:53:28 -05001915static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10001916{
Lyude Paul12a280c2019-06-20 17:59:25 -04001917 topology_ref_history_lock(port->mgr);
1918
Lyude Paul3a08f532021-04-23 14:43:09 -04001919 drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref) - 1);
Lyude Paul12a280c2019-06-20 17:59:25 -04001920 save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_PUT);
1921
1922 topology_ref_history_unlock(port->mgr);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001923 kref_put(&port->topology_kref, drm_dp_destroy_port);
Dave Airliead7f8a12014-06-05 14:01:32 +10001924}
1925
Lyude Pauld0757af2019-01-10 19:53:28 -05001926static struct drm_dp_mst_branch *
1927drm_dp_mst_topology_get_mstb_validated_locked(struct drm_dp_mst_branch *mstb,
1928 struct drm_dp_mst_branch *to_find)
Dave Airliead7f8a12014-06-05 14:01:32 +10001929{
1930 struct drm_dp_mst_port *port;
1931 struct drm_dp_mst_branch *rmstb;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001932
1933 if (to_find == mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10001934 return mstb;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001935
Dave Airliead7f8a12014-06-05 14:01:32 +10001936 list_for_each_entry(port, &mstb->ports, next) {
1937 if (port->mstb) {
Lyude Pauld0757af2019-01-10 19:53:28 -05001938 rmstb = drm_dp_mst_topology_get_mstb_validated_locked(
1939 port->mstb, to_find);
Dave Airliead7f8a12014-06-05 14:01:32 +10001940 if (rmstb)
1941 return rmstb;
1942 }
1943 }
1944 return NULL;
1945}
1946
Lyude Pauld0757af2019-01-10 19:53:28 -05001947static struct drm_dp_mst_branch *
1948drm_dp_mst_topology_get_mstb_validated(struct drm_dp_mst_topology_mgr *mgr,
1949 struct drm_dp_mst_branch *mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10001950{
1951 struct drm_dp_mst_branch *rmstb = NULL;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001952
Dave Airliead7f8a12014-06-05 14:01:32 +10001953 mutex_lock(&mgr->lock);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001954 if (mgr->mst_primary) {
Lyude Pauld0757af2019-01-10 19:53:28 -05001955 rmstb = drm_dp_mst_topology_get_mstb_validated_locked(
1956 mgr->mst_primary, mstb);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001957
1958 if (rmstb && !drm_dp_mst_topology_try_get_mstb(rmstb))
1959 rmstb = NULL;
1960 }
Dave Airliead7f8a12014-06-05 14:01:32 +10001961 mutex_unlock(&mgr->lock);
1962 return rmstb;
1963}
1964
Lyude Paulebcc0e62019-01-10 19:53:29 -05001965static struct drm_dp_mst_port *
1966drm_dp_mst_topology_get_port_validated_locked(struct drm_dp_mst_branch *mstb,
1967 struct drm_dp_mst_port *to_find)
Dave Airliead7f8a12014-06-05 14:01:32 +10001968{
1969 struct drm_dp_mst_port *port, *mport;
1970
1971 list_for_each_entry(port, &mstb->ports, next) {
Lyude Paulebcc0e62019-01-10 19:53:29 -05001972 if (port == to_find)
Dave Airliead7f8a12014-06-05 14:01:32 +10001973 return port;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001974
Dave Airliead7f8a12014-06-05 14:01:32 +10001975 if (port->mstb) {
Lyude Paulebcc0e62019-01-10 19:53:29 -05001976 mport = drm_dp_mst_topology_get_port_validated_locked(
1977 port->mstb, to_find);
Dave Airliead7f8a12014-06-05 14:01:32 +10001978 if (mport)
1979 return mport;
1980 }
1981 }
1982 return NULL;
1983}
1984
Lyude Pauld0757af2019-01-10 19:53:28 -05001985static struct drm_dp_mst_port *
1986drm_dp_mst_topology_get_port_validated(struct drm_dp_mst_topology_mgr *mgr,
1987 struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10001988{
1989 struct drm_dp_mst_port *rport = NULL;
Lyude Paulebcc0e62019-01-10 19:53:29 -05001990
Dave Airliead7f8a12014-06-05 14:01:32 +10001991 mutex_lock(&mgr->lock);
Lyude Paulebcc0e62019-01-10 19:53:29 -05001992 if (mgr->mst_primary) {
1993 rport = drm_dp_mst_topology_get_port_validated_locked(
1994 mgr->mst_primary, port);
1995
1996 if (rport && !drm_dp_mst_topology_try_get_port(rport))
1997 rport = NULL;
1998 }
Dave Airliead7f8a12014-06-05 14:01:32 +10001999 mutex_unlock(&mgr->lock);
2000 return rport;
2001}
2002
2003static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
2004{
2005 struct drm_dp_mst_port *port;
Lyude Paulebcc0e62019-01-10 19:53:29 -05002006 int ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002007
2008 list_for_each_entry(port, &mstb->ports, next) {
2009 if (port->port_num == port_num) {
Lyude Paulebcc0e62019-01-10 19:53:29 -05002010 ret = drm_dp_mst_topology_try_get_port(port);
2011 return ret ? port : NULL;
Dave Airliead7f8a12014-06-05 14:01:32 +10002012 }
2013 }
2014
2015 return NULL;
2016}
2017
2018/*
2019 * calculate a new RAD for this MST branch device
2020 * if parent has an LCT of 2 then it has 1 nibble of RAD,
2021 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
2022 */
2023static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
2024 u8 *rad)
2025{
Mykola Lysenko75af4c82015-12-25 16:14:47 +08002026 int parent_lct = port->parent->lct;
Dave Airliead7f8a12014-06-05 14:01:32 +10002027 int shift = 4;
Mykola Lysenko75af4c82015-12-25 16:14:47 +08002028 int idx = (parent_lct - 1) / 2;
Suraj Upadhyay948de8422020-07-02 18:53:32 +05302029
Mykola Lysenko75af4c82015-12-25 16:14:47 +08002030 if (parent_lct > 1) {
2031 memcpy(rad, port->parent->rad, idx + 1);
2032 shift = (parent_lct % 2) ? 4 : 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10002033 } else
2034 rad[0] = 0;
2035
2036 rad[idx] |= port->port_num << shift;
Mykola Lysenko75af4c82015-12-25 16:14:47 +08002037 return parent_lct + 1;
Dave Airliead7f8a12014-06-05 14:01:32 +10002038}
2039
Lyude Paulb2feb1d2020-03-06 18:46:19 -05002040static bool drm_dp_mst_is_end_device(u8 pdt, bool mcs)
Wayne Lindb1a0792020-01-17 14:03:50 +08002041{
2042 switch (pdt) {
2043 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2044 case DP_PEER_DEVICE_SST_SINK:
2045 return true;
2046 case DP_PEER_DEVICE_MST_BRANCHING:
2047 /* For sst branch device */
2048 if (!mcs)
2049 return true;
2050
2051 return false;
2052 }
2053 return true;
2054}
2055
2056static int
2057drm_dp_port_set_pdt(struct drm_dp_mst_port *port, u8 new_pdt,
2058 bool new_mcs)
Dave Airliead7f8a12014-06-05 14:01:32 +10002059{
Lyude Paulc485e2c2019-03-13 13:51:41 -04002060 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2061 struct drm_dp_mst_branch *mstb;
2062 u8 rad[8], lct;
2063 int ret = 0;
2064
Wayne Lindb1a0792020-01-17 14:03:50 +08002065 if (port->pdt == new_pdt && port->mcs == new_mcs)
Lyude Paulc485e2c2019-03-13 13:51:41 -04002066 return 0;
2067
2068 /* Teardown the old pdt, if there is one */
Wayne Lindb1a0792020-01-17 14:03:50 +08002069 if (port->pdt != DP_PEER_DEVICE_NONE) {
Lyude Paulb2feb1d2020-03-06 18:46:19 -05002070 if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) {
Wayne Lindb1a0792020-01-17 14:03:50 +08002071 /*
2072 * If the new PDT would also have an i2c bus,
2073 * don't bother with reregistering it
2074 */
2075 if (new_pdt != DP_PEER_DEVICE_NONE &&
Lyude Paulb2feb1d2020-03-06 18:46:19 -05002076 drm_dp_mst_is_end_device(new_pdt, new_mcs)) {
Wayne Lindb1a0792020-01-17 14:03:50 +08002077 port->pdt = new_pdt;
2078 port->mcs = new_mcs;
2079 return 0;
2080 }
Lyude Paulc485e2c2019-03-13 13:51:41 -04002081
Wayne Lindb1a0792020-01-17 14:03:50 +08002082 /* remove i2c over sideband */
Imre Deakd8bd15b2020-06-08 00:25:21 +03002083 drm_dp_mst_unregister_i2c_bus(port);
Wayne Lindb1a0792020-01-17 14:03:50 +08002084 } else {
2085 mutex_lock(&mgr->lock);
2086 drm_dp_mst_topology_put_mstb(port->mstb);
2087 port->mstb = NULL;
2088 mutex_unlock(&mgr->lock);
2089 }
Lyude Paulc485e2c2019-03-13 13:51:41 -04002090 }
2091
2092 port->pdt = new_pdt;
Wayne Lindb1a0792020-01-17 14:03:50 +08002093 port->mcs = new_mcs;
Lyude Paulc485e2c2019-03-13 13:51:41 -04002094
Wayne Lindb1a0792020-01-17 14:03:50 +08002095 if (port->pdt != DP_PEER_DEVICE_NONE) {
Lyude Paulb2feb1d2020-03-06 18:46:19 -05002096 if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) {
Wayne Lindb1a0792020-01-17 14:03:50 +08002097 /* add i2c over sideband */
Imre Deakd8bd15b2020-06-08 00:25:21 +03002098 ret = drm_dp_mst_register_i2c_bus(port);
Wayne Lindb1a0792020-01-17 14:03:50 +08002099 } else {
2100 lct = drm_dp_calculate_rad(port, rad);
2101 mstb = drm_dp_add_mst_branch_device(lct, rad);
2102 if (!mstb) {
2103 ret = -ENOMEM;
Lyude Paul3a08f532021-04-23 14:43:09 -04002104 drm_err(mgr->dev, "Failed to create MSTB for port %p", port);
Wayne Lindb1a0792020-01-17 14:03:50 +08002105 goto out;
2106 }
2107
2108 mutex_lock(&mgr->lock);
2109 port->mstb = mstb;
2110 mstb->mgr = port->mgr;
2111 mstb->port_parent = port;
2112
2113 /*
2114 * Make sure this port's memory allocation stays
2115 * around until its child MSTB releases it
2116 */
2117 drm_dp_mst_get_port_malloc(port);
2118 mutex_unlock(&mgr->lock);
2119
2120 /* And make sure we send a link address for this */
2121 ret = 1;
Joe Moriarty22a07032018-02-12 14:51:42 -05002122 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002123 }
Lyude Paulc485e2c2019-03-13 13:51:41 -04002124
2125out:
2126 if (ret < 0)
2127 port->pdt = DP_PEER_DEVICE_NONE;
2128 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002129}
2130
Ville Syrjälä562836a22019-07-23 19:28:01 -04002131/**
2132 * drm_dp_mst_dpcd_read() - read a series of bytes from the DPCD via sideband
2133 * @aux: Fake sideband AUX CH
2134 * @offset: address of the (first) register to read
2135 * @buffer: buffer to store the register values
2136 * @size: number of bytes in @buffer
2137 *
2138 * Performs the same functionality for remote devices via
2139 * sideband messaging as drm_dp_dpcd_read() does for local
2140 * devices via actual AUX CH.
2141 *
2142 * Return: Number of bytes read, or negative error code on failure.
2143 */
2144ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux,
2145 unsigned int offset, void *buffer, size_t size)
2146{
2147 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port,
2148 aux);
2149
2150 return drm_dp_send_dpcd_read(port->mgr, port,
2151 offset, size, buffer);
2152}
2153
2154/**
2155 * drm_dp_mst_dpcd_write() - write a series of bytes to the DPCD via sideband
2156 * @aux: Fake sideband AUX CH
2157 * @offset: address of the (first) register to write
2158 * @buffer: buffer containing the values to write
2159 * @size: number of bytes in @buffer
2160 *
2161 * Performs the same functionality for remote devices via
2162 * sideband messaging as drm_dp_dpcd_write() does for local
2163 * devices via actual AUX CH.
2164 *
Lyude Paul4c0a9b62020-03-06 18:49:21 -05002165 * Return: number of bytes written on success, negative error code on failure.
Ville Syrjälä562836a22019-07-23 19:28:01 -04002166 */
2167ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux,
2168 unsigned int offset, void *buffer, size_t size)
2169{
2170 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port,
2171 aux);
2172
2173 return drm_dp_send_dpcd_write(port->mgr, port,
2174 offset, size, buffer);
2175}
2176
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002177static int drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
Dave Airliead7f8a12014-06-05 14:01:32 +10002178{
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002179 int ret = 0;
Hersen Wu5e93b822016-01-22 17:07:28 -05002180
2181 memcpy(mstb->guid, guid, 16);
2182
2183 if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) {
2184 if (mstb->port_parent) {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002185 ret = drm_dp_send_dpcd_write(mstb->mgr,
2186 mstb->port_parent,
2187 DP_GUID, 16, mstb->guid);
Hersen Wu5e93b822016-01-22 17:07:28 -05002188 } else {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002189 ret = drm_dp_dpcd_write(mstb->mgr->aux,
2190 DP_GUID, mstb->guid, 16);
Dave Airliead7f8a12014-06-05 14:01:32 +10002191 }
2192 }
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002193
Lyude Paul94b6ada2020-03-06 18:49:22 -05002194 if (ret < 16 && ret > 0)
2195 return -EPROTO;
2196
2197 return ret == 16 ? 0 : ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002198}
2199
Dave Airlie1c960872015-09-16 11:04:49 +10002200static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
2201 int pnum,
Rickard Strandqvistd87af4d2014-10-12 00:02:32 +02002202 char *proppath,
2203 size_t proppath_size)
Dave Airliead7f8a12014-06-05 14:01:32 +10002204{
2205 int i;
2206 char temp[8];
Suraj Upadhyay948de8422020-07-02 18:53:32 +05302207
Rickard Strandqvistd87af4d2014-10-12 00:02:32 +02002208 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
Dave Airliead7f8a12014-06-05 14:01:32 +10002209 for (i = 0; i < (mstb->lct - 1); i++) {
2210 int shift = (i % 2) ? 0 : 4;
Mykola Lysenko7a11a332015-12-25 16:14:48 +08002211 int port_num = (mstb->rad[i / 2] >> shift) & 0xf;
Suraj Upadhyay948de8422020-07-02 18:53:32 +05302212
Rickard Strandqvistd87af4d2014-10-12 00:02:32 +02002213 snprintf(temp, sizeof(temp), "-%d", port_num);
2214 strlcat(proppath, temp, proppath_size);
Dave Airliead7f8a12014-06-05 14:01:32 +10002215 }
Dave Airlie1c960872015-09-16 11:04:49 +10002216 snprintf(temp, sizeof(temp), "-%d", pnum);
Rickard Strandqvistd87af4d2014-10-12 00:02:32 +02002217 strlcat(proppath, temp, proppath_size);
Dave Airliead7f8a12014-06-05 14:01:32 +10002218}
2219
Ville Syrjälä562836a22019-07-23 19:28:01 -04002220/**
2221 * drm_dp_mst_connector_late_register() - Late MST connector registration
Sean Paul63b87c32019-07-26 10:20:47 -04002222 * @connector: The MST connector
Ville Syrjälä562836a22019-07-23 19:28:01 -04002223 * @port: The MST port for this connector
2224 *
2225 * Helper to register the remote aux device for this MST port. Drivers should
2226 * call this from their mst connector's late_register hook to enable MST aux
2227 * devices.
2228 *
2229 * Return: 0 on success, negative error code on failure.
2230 */
2231int drm_dp_mst_connector_late_register(struct drm_connector *connector,
2232 struct drm_dp_mst_port *port)
2233{
Lyude Paul3a08f532021-04-23 14:43:09 -04002234 drm_dbg_kms(port->mgr->dev, "registering %s remote bus for %s\n",
2235 port->aux.name, connector->kdev->kobj.name);
Ville Syrjälä562836a22019-07-23 19:28:01 -04002236
2237 port->aux.dev = connector->kdev;
2238 return drm_dp_aux_register_devnode(&port->aux);
2239}
2240EXPORT_SYMBOL(drm_dp_mst_connector_late_register);
2241
2242/**
2243 * drm_dp_mst_connector_early_unregister() - Early MST connector unregistration
Sean Paul63b87c32019-07-26 10:20:47 -04002244 * @connector: The MST connector
Ville Syrjälä562836a22019-07-23 19:28:01 -04002245 * @port: The MST port for this connector
2246 *
2247 * Helper to unregister the remote aux device for this MST port, registered by
2248 * drm_dp_mst_connector_late_register(). Drivers should call this from their mst
2249 * connector's early_unregister hook.
2250 */
2251void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
2252 struct drm_dp_mst_port *port)
2253{
Lyude Paul3a08f532021-04-23 14:43:09 -04002254 drm_dbg_kms(port->mgr->dev, "unregistering %s remote bus for %s\n",
2255 port->aux.name, connector->kdev->kobj.name);
Ville Syrjälä562836a22019-07-23 19:28:01 -04002256 drm_dp_aux_unregister_devnode(&port->aux);
2257}
2258EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister);
2259
Lyude Paule2839ff2019-09-03 16:45:55 -04002260static void
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002261drm_dp_mst_port_add_connector(struct drm_dp_mst_branch *mstb,
2262 struct drm_dp_mst_port *port)
2263{
2264 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2265 char proppath[255];
2266 int ret;
2267
2268 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath));
2269 port->connector = mgr->cbs->add_connector(mgr, port, proppath);
2270 if (!port->connector) {
2271 ret = -ENOMEM;
2272 goto error;
2273 }
2274
Wayne Lindb1a0792020-01-17 14:03:50 +08002275 if (port->pdt != DP_PEER_DEVICE_NONE &&
Imre Deak4b8878e2021-02-01 14:01:43 +02002276 drm_dp_mst_is_end_device(port->pdt, port->mcs) &&
Imre Deakca5d9d72024-04-17 01:10:07 +03002277 drm_dp_mst_port_is_logical(port))
Jani Nikulac1c90422023-05-30 12:08:24 +03002278 port->cached_edid = drm_edid_read_ddc(port->connector,
2279 &port->aux.ddc);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002280
Pankaj Bharadiyaf8d97d92020-03-07 14:00:19 +05302281 drm_connector_register(port->connector);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002282 return;
2283
2284error:
Lyude Paul3a08f532021-04-23 14:43:09 -04002285 drm_err(mgr->dev, "Failed to create connector for port %p: %d\n", port, ret);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002286}
2287
2288/*
2289 * Drop a topology reference, and unlink the port from the in-memory topology
2290 * layout
2291 */
2292static void
2293drm_dp_mst_topology_unlink_port(struct drm_dp_mst_topology_mgr *mgr,
2294 struct drm_dp_mst_port *port)
2295{
2296 mutex_lock(&mgr->lock);
David Francisb1dee9a72019-07-25 11:47:46 -04002297 port->parent->num_ports--;
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002298 list_del(&port->next);
2299 mutex_unlock(&mgr->lock);
2300 drm_dp_mst_topology_put_port(port);
2301}
2302
2303static struct drm_dp_mst_port *
2304drm_dp_mst_add_port(struct drm_device *dev,
2305 struct drm_dp_mst_topology_mgr *mgr,
2306 struct drm_dp_mst_branch *mstb, u8 port_number)
2307{
2308 struct drm_dp_mst_port *port = kzalloc(sizeof(*port), GFP_KERNEL);
2309
2310 if (!port)
2311 return NULL;
2312
2313 kref_init(&port->topology_kref);
2314 kref_init(&port->malloc_kref);
2315 port->parent = mstb;
2316 port->port_num = port_number;
2317 port->mgr = mgr;
2318 port->aux.name = "DPMST";
2319 port->aux.dev = dev->dev;
2320 port->aux.is_remote = true;
2321
David (Dingchen) Zhangc908b1c2019-12-06 17:56:37 -05002322 /* initialize the MST downstream port's AUX crc work queue */
Lyude Paul6cba3fe2021-04-23 14:42:55 -04002323 port->aux.drm_dev = dev;
David (Dingchen) Zhangc908b1c2019-12-06 17:56:37 -05002324 drm_dp_remote_aux_init(&port->aux);
2325
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002326 /*
2327 * Make sure the memory allocation for our parent branch stays
2328 * around until our own memory allocation is released
2329 */
2330 drm_dp_mst_get_mstb_malloc(mstb);
2331
2332 return port;
2333}
2334
Lyude Paul6f85f732019-06-17 19:57:33 -04002335static int
Lyude Paule2839ff2019-09-03 16:45:55 -04002336drm_dp_mst_handle_link_address_port(struct drm_dp_mst_branch *mstb,
2337 struct drm_device *dev,
2338 struct drm_dp_link_addr_reply_port *port_msg)
Dave Airliead7f8a12014-06-05 14:01:32 +10002339{
Lyude Paulc485e2c2019-03-13 13:51:41 -04002340 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
Dave Airliead7f8a12014-06-05 14:01:32 +10002341 struct drm_dp_mst_port *port;
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002342 int old_ddps = 0, ret;
2343 u8 new_pdt = DP_PEER_DEVICE_NONE;
Wayne Lindb1a0792020-01-17 14:03:50 +08002344 bool new_mcs = 0;
Lyude Paul6f85f732019-06-17 19:57:33 -04002345 bool created = false, send_link_addr = false, changed = false;
Lyude Paulebcc0e62019-01-10 19:53:29 -05002346
Dave Airliead7f8a12014-06-05 14:01:32 +10002347 port = drm_dp_get_port(mstb, port_msg->port_number);
2348 if (!port) {
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002349 port = drm_dp_mst_add_port(dev, mgr, mstb,
2350 port_msg->port_number);
Dave Airliead7f8a12014-06-05 14:01:32 +10002351 if (!port)
Lyude Paul6f85f732019-06-17 19:57:33 -04002352 return -ENOMEM;
Dave Airliead7f8a12014-06-05 14:01:32 +10002353 created = true;
Lyude Paul6f85f732019-06-17 19:57:33 -04002354 changed = true;
2355 } else if (!port->input && port_msg->input_port && port->connector) {
2356 /* Since port->connector can't be changed here, we create a
2357 * new port if input_port changes from 0 to 1
Dave Airliead7f8a12014-06-05 14:01:32 +10002358 */
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002359 drm_dp_mst_topology_unlink_port(mgr, port);
2360 drm_dp_mst_topology_put_port(port);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002361 port = drm_dp_mst_add_port(dev, mgr, mstb,
2362 port_msg->port_number);
2363 if (!port)
Lyude Paul6f85f732019-06-17 19:57:33 -04002364 return -ENOMEM;
2365 changed = true;
Dave Airliead7f8a12014-06-05 14:01:32 +10002366 created = true;
Lyude Paul6f85f732019-06-17 19:57:33 -04002367 } else if (port->input && !port_msg->input_port) {
2368 changed = true;
2369 } else if (port->connector) {
2370 /* We're updating a port that's exposed to userspace, so do it
2371 * under lock
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002372 */
2373 drm_modeset_lock(&mgr->base.lock, NULL);
Lyude Paul6f85f732019-06-17 19:57:33 -04002374
Dave Airliead7f8a12014-06-05 14:01:32 +10002375 old_ddps = port->ddps;
Lyude Paul6f85f732019-06-17 19:57:33 -04002376 changed = port->ddps != port_msg->ddps ||
2377 (port->ddps &&
2378 (port->ldps != port_msg->legacy_device_plug_status ||
2379 port->dpcd_rev != port_msg->dpcd_revision ||
2380 port->mcs != port_msg->mcs ||
2381 port->pdt != port_msg->peer_device_type ||
2382 port->num_sdp_stream_sinks !=
2383 port_msg->num_sdp_stream_sinks));
Dave Airliead7f8a12014-06-05 14:01:32 +10002384 }
2385
Dave Airliead7f8a12014-06-05 14:01:32 +10002386 port->input = port_msg->input_port;
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002387 if (!port->input)
2388 new_pdt = port_msg->peer_device_type;
Wayne Lindb1a0792020-01-17 14:03:50 +08002389 new_mcs = port_msg->mcs;
Dave Airliead7f8a12014-06-05 14:01:32 +10002390 port->ddps = port_msg->ddps;
2391 port->ldps = port_msg->legacy_device_plug_status;
2392 port->dpcd_rev = port_msg->dpcd_revision;
2393 port->num_sdp_streams = port_msg->num_sdp_streams;
2394 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
Dave Airliead7f8a12014-06-05 14:01:32 +10002395
2396 /* manage mstb port lists with mgr lock - take a reference
2397 for this list */
2398 if (created) {
Lyude Paulc485e2c2019-03-13 13:51:41 -04002399 mutex_lock(&mgr->lock);
Lyude Paulebcc0e62019-01-10 19:53:29 -05002400 drm_dp_mst_topology_get_port(port);
Dave Airliead7f8a12014-06-05 14:01:32 +10002401 list_add(&port->next, &mstb->ports);
David Francisb1dee9a72019-07-25 11:47:46 -04002402 mstb->num_ports++;
Lyude Paulc485e2c2019-03-13 13:51:41 -04002403 mutex_unlock(&mgr->lock);
Dave Airliead7f8a12014-06-05 14:01:32 +10002404 }
2405
Lyude Paul87212b52020-03-06 18:46:21 -05002406 /*
2407 * Reprobe PBN caps on both hotplug, and when re-probing the link
2408 * for our parent mstb
2409 */
2410 if (old_ddps != port->ddps || !created) {
2411 if (port->ddps && !port->input) {
2412 ret = drm_dp_send_enum_path_resources(mgr, mstb,
2413 port);
2414 if (ret == 1)
2415 changed = true;
Dave Airliead7f8a12014-06-05 14:01:32 +10002416 } else {
Lyude Paulfcf46382020-03-06 18:46:20 -05002417 port->full_pbn = 0;
Lyude Paul3d76df62019-01-10 19:53:24 -05002418 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002419 }
2420
Wayne Lindb1a0792020-01-17 14:03:50 +08002421 ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002422 if (ret == 1) {
2423 send_link_addr = true;
2424 } else if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002425 drm_err(dev, "Failed to change PDT on port %p: %d\n", port, ret);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002426 goto fail;
Dave Airliead7f8a12014-06-05 14:01:32 +10002427 }
2428
Lyude Paul6f85f732019-06-17 19:57:33 -04002429 /*
2430 * If this port wasn't just created, then we're reprobing because
2431 * we're coming out of suspend. In this case, always resend the link
2432 * address if there's an MSTB on this port
2433 */
Wayne Lindb1a0792020-01-17 14:03:50 +08002434 if (!created && port->pdt == DP_PEER_DEVICE_MST_BRANCHING &&
2435 port->mcs)
Lyude Paul6f85f732019-06-17 19:57:33 -04002436 send_link_addr = true;
Dave Airlie1c960872015-09-16 11:04:49 +10002437
Lyude Paul6f85f732019-06-17 19:57:33 -04002438 if (port->connector)
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002439 drm_modeset_unlock(&mgr->base.lock);
Lyude Paul6f85f732019-06-17 19:57:33 -04002440 else if (!port->input)
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002441 drm_dp_mst_port_add_connector(mstb, port);
Dave Airlie1c960872015-09-16 11:04:49 +10002442
Lyude Paul6f85f732019-06-17 19:57:33 -04002443 if (send_link_addr && port->mstb) {
2444 ret = drm_dp_send_link_address(mgr, port->mstb);
2445 if (ret == 1) /* MSTB below us changed */
2446 changed = true;
2447 else if (ret < 0)
2448 goto fail_put;
Dave Airliead7f8a12014-06-05 14:01:32 +10002449 }
Dave Airlie8ae22cb2016-02-17 11:36:38 +10002450
Dave Airliead7f8a12014-06-05 14:01:32 +10002451 /* put reference to this port */
Lyude Pauld0757af2019-01-10 19:53:28 -05002452 drm_dp_mst_topology_put_port(port);
Lyude Paul6f85f732019-06-17 19:57:33 -04002453 return changed;
Lyude Paulc485e2c2019-03-13 13:51:41 -04002454
2455fail:
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002456 drm_dp_mst_topology_unlink_port(mgr, port);
Lyude Paul6f85f732019-06-17 19:57:33 -04002457 if (port->connector)
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002458 drm_modeset_unlock(&mgr->base.lock);
Lyude Paul6f85f732019-06-17 19:57:33 -04002459fail_put:
2460 drm_dp_mst_topology_put_port(port);
2461 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002462}
2463
Lyude Paul2482fce2022-08-17 15:38:43 -04002464static int
Lyude Paule2839ff2019-09-03 16:45:55 -04002465drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb,
2466 struct drm_dp_connection_status_notify *conn_stat)
Dave Airliead7f8a12014-06-05 14:01:32 +10002467{
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002468 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
Dave Airliead7f8a12014-06-05 14:01:32 +10002469 struct drm_dp_mst_port *port;
Wayne Lin35d3e8c2021-06-16 11:55:00 +08002470 int old_ddps, ret;
Lyude Pauldad7d842019-10-16 17:50:15 -04002471 u8 new_pdt;
Wayne Lindb1a0792020-01-17 14:03:50 +08002472 bool new_mcs;
Lyude Pauldad7d842019-10-16 17:50:15 -04002473 bool dowork = false, create_connector = false;
Lyude Paulc485e2c2019-03-13 13:51:41 -04002474
Dave Airliead7f8a12014-06-05 14:01:32 +10002475 port = drm_dp_get_port(mstb, conn_stat->port_number);
2476 if (!port)
Lyude Paul2482fce2022-08-17 15:38:43 -04002477 return 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10002478
Lyude Pauldad7d842019-10-16 17:50:15 -04002479 if (port->connector) {
2480 if (!port->input && conn_stat->input_port) {
2481 /*
2482 * We can't remove a connector from an already exposed
2483 * port, so just throw the port out and make sure we
2484 * reprobe the link address of it's parent MSTB
2485 */
2486 drm_dp_mst_topology_unlink_port(mgr, port);
2487 mstb->link_address_sent = false;
2488 dowork = true;
2489 goto out;
2490 }
2491
2492 /* Locking is only needed if the port's exposed to userspace */
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002493 drm_modeset_lock(&mgr->base.lock, NULL);
Lyude Pauldad7d842019-10-16 17:50:15 -04002494 } else if (port->input && !conn_stat->input_port) {
2495 create_connector = true;
2496 /* Reprobe link address so we get num_sdp_streams */
2497 mstb->link_address_sent = false;
2498 dowork = true;
2499 }
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002500
Dave Airliead7f8a12014-06-05 14:01:32 +10002501 old_ddps = port->ddps;
Lyude Pauldad7d842019-10-16 17:50:15 -04002502 port->input = conn_stat->input_port;
Dave Airliead7f8a12014-06-05 14:01:32 +10002503 port->ldps = conn_stat->legacy_device_plug_status;
2504 port->ddps = conn_stat->displayport_device_plug_status;
2505
2506 if (old_ddps != port->ddps) {
Lyude Paul87212b52020-03-06 18:46:21 -05002507 if (port->ddps && !port->input)
2508 drm_dp_send_enum_path_resources(mgr, mstb, port);
2509 else
Lyude Paulfcf46382020-03-06 18:46:20 -05002510 port->full_pbn = 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10002511 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002512
Lyude Pauldad7d842019-10-16 17:50:15 -04002513 new_pdt = port->input ? DP_PEER_DEVICE_NONE : conn_stat->peer_device_type;
Wayne Lindb1a0792020-01-17 14:03:50 +08002514 new_mcs = conn_stat->message_capability_status;
2515 ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs);
Lyude Pauldad7d842019-10-16 17:50:15 -04002516 if (ret == 1) {
2517 dowork = true;
2518 } else if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002519 drm_err(mgr->dev, "Failed to change PDT for port %p: %d\n", port, ret);
Lyude Pauldad7d842019-10-16 17:50:15 -04002520 dowork = false;
Dave Airliead7f8a12014-06-05 14:01:32 +10002521 }
2522
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002523 if (port->connector)
2524 drm_modeset_unlock(&mgr->base.lock);
Lyude Pauldad7d842019-10-16 17:50:15 -04002525 else if (create_connector)
2526 drm_dp_mst_port_add_connector(mstb, port);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002527
Lyude Pauldad7d842019-10-16 17:50:15 -04002528out:
Lyude Pauld0757af2019-01-10 19:53:28 -05002529 drm_dp_mst_topology_put_port(port);
Lyude Paul2482fce2022-08-17 15:38:43 -04002530 return dowork;
Dave Airliead7f8a12014-06-05 14:01:32 +10002531}
2532
2533static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
2534 u8 lct, u8 *rad)
2535{
2536 struct drm_dp_mst_branch *mstb;
2537 struct drm_dp_mst_port *port;
Lyude Paulebcc0e62019-01-10 19:53:29 -05002538 int i, ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002539 /* find the port by iterating down */
Dave Airlie9eb1e572015-06-22 14:40:44 +10002540
2541 mutex_lock(&mgr->lock);
Dave Airliead7f8a12014-06-05 14:01:32 +10002542 mstb = mgr->mst_primary;
2543
Stanislav Lisovskiy23d80032018-11-09 11:00:12 +02002544 if (!mstb)
2545 goto out;
2546
Dave Airliead7f8a12014-06-05 14:01:32 +10002547 for (i = 0; i < lct - 1; i++) {
2548 int shift = (i % 2) ? 0 : 4;
Mykola Lysenko7a11a332015-12-25 16:14:48 +08002549 int port_num = (rad[i / 2] >> shift) & 0xf;
Dave Airliead7f8a12014-06-05 14:01:32 +10002550
2551 list_for_each_entry(port, &mstb->ports, next) {
2552 if (port->port_num == port_num) {
Adam Richter30730c72015-10-16 03:33:02 -07002553 mstb = port->mstb;
2554 if (!mstb) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002555 drm_err(mgr->dev,
2556 "failed to lookup MSTB with lct %d, rad %02x\n",
2557 lct, rad[0]);
Adam Richter30730c72015-10-16 03:33:02 -07002558 goto out;
Dave Airliead7f8a12014-06-05 14:01:32 +10002559 }
2560
Dave Airliead7f8a12014-06-05 14:01:32 +10002561 break;
2562 }
2563 }
2564 }
Lyude Paulebcc0e62019-01-10 19:53:29 -05002565 ret = drm_dp_mst_topology_try_get_mstb(mstb);
2566 if (!ret)
2567 mstb = NULL;
Adam Richter30730c72015-10-16 03:33:02 -07002568out:
Dave Airlie9eb1e572015-06-22 14:40:44 +10002569 mutex_unlock(&mgr->lock);
Dave Airliead7f8a12014-06-05 14:01:32 +10002570 return mstb;
2571}
2572
Mykola Lysenkobd934322015-12-18 17:14:42 -05002573static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
2574 struct drm_dp_mst_branch *mstb,
Lyude Paulfde61a72019-09-03 16:45:49 -04002575 const uint8_t *guid)
Mykola Lysenkobd934322015-12-18 17:14:42 -05002576{
2577 struct drm_dp_mst_branch *found_mstb;
2578 struct drm_dp_mst_port *port;
2579
Lukasz Majczak3d887d52023-09-22 08:34:10 +02002580 if (!mstb)
2581 return NULL;
2582
Hersen Wu5e93b822016-01-22 17:07:28 -05002583 if (memcmp(mstb->guid, guid, 16) == 0)
2584 return mstb;
2585
2586
Mykola Lysenkobd934322015-12-18 17:14:42 -05002587 list_for_each_entry(port, &mstb->ports, next) {
Mykola Lysenkobd934322015-12-18 17:14:42 -05002588 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
2589
2590 if (found_mstb)
2591 return found_mstb;
2592 }
2593
2594 return NULL;
2595}
2596
Lyude Paulde6d6812019-01-10 19:53:25 -05002597static struct drm_dp_mst_branch *
2598drm_dp_get_mst_branch_device_by_guid(struct drm_dp_mst_topology_mgr *mgr,
Lyude Paulfde61a72019-09-03 16:45:49 -04002599 const uint8_t *guid)
Mykola Lysenkobd934322015-12-18 17:14:42 -05002600{
2601 struct drm_dp_mst_branch *mstb;
Lyude Paulebcc0e62019-01-10 19:53:29 -05002602 int ret;
Mykola Lysenkobd934322015-12-18 17:14:42 -05002603
2604 /* find the port by iterating down */
2605 mutex_lock(&mgr->lock);
2606
Hersen Wu5e93b822016-01-22 17:07:28 -05002607 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid);
Lyude Paulebcc0e62019-01-10 19:53:29 -05002608 if (mstb) {
2609 ret = drm_dp_mst_topology_try_get_mstb(mstb);
2610 if (!ret)
2611 mstb = NULL;
2612 }
Mykola Lysenkobd934322015-12-18 17:14:42 -05002613
2614 mutex_unlock(&mgr->lock);
2615 return mstb;
2616}
2617
Lyude Paul6f85f732019-06-17 19:57:33 -04002618static int drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
Dave Airliead7f8a12014-06-05 14:01:32 +10002619 struct drm_dp_mst_branch *mstb)
2620{
2621 struct drm_dp_mst_port *port;
Lyude Paul6f85f732019-06-17 19:57:33 -04002622 int ret;
2623 bool changed = false;
Lyude Paul14692a32019-10-16 16:02:59 -04002624
Lyude Paul6f85f732019-06-17 19:57:33 -04002625 if (!mstb->link_address_sent) {
2626 ret = drm_dp_send_link_address(mgr, mstb);
2627 if (ret == 1)
2628 changed = true;
2629 else if (ret < 0)
2630 return ret;
2631 }
Dave Airlie68d8c9f2015-09-06 18:53:00 +10002632
Dave Airliead7f8a12014-06-05 14:01:32 +10002633 list_for_each_entry(port, &mstb->ports, next) {
Lyude Paule21c3ad2022-06-02 16:17:55 -04002634 if (port->input || !port->ddps || !port->mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10002635 continue;
2636
Lyude Paule21c3ad2022-06-02 16:17:55 -04002637 ret = drm_dp_check_and_send_link_address(mgr, port->mstb);
2638 if (ret == 1)
2639 changed = true;
2640 else if (ret < 0)
2641 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10002642 }
Lyude Paul6f85f732019-06-17 19:57:33 -04002643
2644 return changed;
Dave Airliead7f8a12014-06-05 14:01:32 +10002645}
2646
2647static void drm_dp_mst_link_probe_work(struct work_struct *work)
2648{
Lyude Paul14692a32019-10-16 16:02:59 -04002649 struct drm_dp_mst_topology_mgr *mgr =
2650 container_of(work, struct drm_dp_mst_topology_mgr, work);
2651 struct drm_device *dev = mgr->dev;
Daniel Vetter9254ec42015-06-22 17:31:59 +10002652 struct drm_dp_mst_branch *mstb;
Lyude Paulebcc0e62019-01-10 19:53:29 -05002653 int ret;
Sean Paulf7948902019-08-28 20:09:44 -04002654 bool clear_payload_id_table;
Dave Airliead7f8a12014-06-05 14:01:32 +10002655
Lyude Paul14692a32019-10-16 16:02:59 -04002656 mutex_lock(&mgr->probe_lock);
2657
Daniel Vetter9254ec42015-06-22 17:31:59 +10002658 mutex_lock(&mgr->lock);
Sean Paulf7948902019-08-28 20:09:44 -04002659 clear_payload_id_table = !mgr->payload_id_table_cleared;
2660 mgr->payload_id_table_cleared = true;
2661
Daniel Vetter9254ec42015-06-22 17:31:59 +10002662 mstb = mgr->mst_primary;
2663 if (mstb) {
Lyude Paulebcc0e62019-01-10 19:53:29 -05002664 ret = drm_dp_mst_topology_try_get_mstb(mstb);
2665 if (!ret)
2666 mstb = NULL;
Daniel Vetter9254ec42015-06-22 17:31:59 +10002667 }
2668 mutex_unlock(&mgr->lock);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002669 if (!mstb) {
2670 mutex_unlock(&mgr->probe_lock);
2671 return;
Daniel Vetter9254ec42015-06-22 17:31:59 +10002672 }
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002673
Sean Paulf7948902019-08-28 20:09:44 -04002674 /*
2675 * Certain branch devices seem to incorrectly report an available_pbn
2676 * of 0 on downstream sinks, even after clearing the
2677 * DP_PAYLOAD_ALLOCATE_* registers in
2678 * drm_dp_mst_topology_mgr_set_mst(). Namely, the CableMatters USB-C
2679 * 2x DP hub. Sending a CLEAR_PAYLOAD_ID_TABLE message seems to make
2680 * things work again.
2681 */
2682 if (clear_payload_id_table) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002683 drm_dbg_kms(dev, "Clearing payload ID table\n");
Sean Paulf7948902019-08-28 20:09:44 -04002684 drm_dp_send_clear_payload_id_table(mgr, mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10002685 }
Sean Paulf7948902019-08-28 20:09:44 -04002686
Lyude Paul6f85f732019-06-17 19:57:33 -04002687 ret = drm_dp_check_and_send_link_address(mgr, mstb);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04002688 drm_dp_mst_topology_put_mstb(mstb);
2689
Lyude Paul14692a32019-10-16 16:02:59 -04002690 mutex_unlock(&mgr->probe_lock);
Xiaogang Chendc25e372021-01-12 06:36:52 +00002691 if (ret > 0)
Lyude Paul6f85f732019-06-17 19:57:33 -04002692 drm_kms_helper_hotplug_event(dev);
Dave Airliead7f8a12014-06-05 14:01:32 +10002693}
2694
2695static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
2696 u8 *guid)
2697{
Ville Syrjäläe38e1282017-07-12 18:52:54 +03002698 u64 salt;
Dave Airliead7f8a12014-06-05 14:01:32 +10002699
Ville Syrjäläe38e1282017-07-12 18:52:54 +03002700 if (memchr_inv(guid, 0, 16))
2701 return true;
2702
2703 salt = get_jiffies_64();
2704
2705 memcpy(&guid[0], &salt, sizeof(u64));
2706 memcpy(&guid[8], &salt, sizeof(u64));
2707
2708 return false;
Dave Airliead7f8a12014-06-05 14:01:32 +10002709}
2710
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002711static void build_dpcd_read(struct drm_dp_sideband_msg_tx *msg,
2712 u8 port_num, u32 offset, u8 num_bytes)
Dave Airliead7f8a12014-06-05 14:01:32 +10002713{
2714 struct drm_dp_sideband_msg_req_body req;
2715
2716 req.req_type = DP_REMOTE_DPCD_READ;
2717 req.u.dpcd_read.port_number = port_num;
2718 req.u.dpcd_read.dpcd_address = offset;
2719 req.u.dpcd_read.num_bytes = num_bytes;
2720 drm_dp_encode_sideband_req(&req, msg);
Dave Airliead7f8a12014-06-05 14:01:32 +10002721}
Dave Airliead7f8a12014-06-05 14:01:32 +10002722
2723static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
2724 bool up, u8 *msg, int len)
2725{
2726 int ret;
2727 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
2728 int tosend, total, offset;
2729 int retries = 0;
2730
2731retry:
2732 total = len;
2733 offset = 0;
2734 do {
2735 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
2736
2737 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
2738 &msg[offset],
2739 tosend);
2740 if (ret != tosend) {
2741 if (ret == -EIO && retries < 5) {
2742 retries++;
2743 goto retry;
2744 }
Lyude Paul3a08f532021-04-23 14:43:09 -04002745 drm_dbg_kms(mgr->dev, "failed to dpcd write %d %d\n", tosend, ret);
Dave Airliead7f8a12014-06-05 14:01:32 +10002746
2747 return -EIO;
2748 }
2749 offset += tosend;
2750 total -= tosend;
2751 } while (total > 0);
2752 return 0;
2753}
2754
2755static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
2756 struct drm_dp_sideband_msg_tx *txmsg)
2757{
2758 struct drm_dp_mst_branch *mstb = txmsg->dst;
Mykola Lysenkobd934322015-12-18 17:14:42 -05002759 u8 req_type;
Dave Airliead7f8a12014-06-05 14:01:32 +10002760
Mykola Lysenkobd934322015-12-18 17:14:42 -05002761 req_type = txmsg->msg[0] & 0x7f;
2762 if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
Wayne Lind919d3d2021-02-24 18:15:21 +08002763 req_type == DP_RESOURCE_STATUS_NOTIFY ||
2764 req_type == DP_CLEAR_PAYLOAD_ID_TABLE)
Mykola Lysenkobd934322015-12-18 17:14:42 -05002765 hdr->broadcast = 1;
2766 else
2767 hdr->broadcast = 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10002768 hdr->path_msg = txmsg->path_msg;
Wayne Lin419e91e2021-02-24 18:15:20 +08002769 if (hdr->broadcast) {
2770 hdr->lct = 1;
2771 hdr->lcr = 6;
2772 } else {
2773 hdr->lct = mstb->lct;
2774 hdr->lcr = mstb->lct - 1;
2775 }
2776
2777 memcpy(hdr->rad, mstb->rad, hdr->lct / 2);
Lyude Pauld308a882020-04-24 14:13:08 -04002778
Dave Airliead7f8a12014-06-05 14:01:32 +10002779 return 0;
2780}
2781/*
2782 * process a single block of the next message in the sideband queue
2783 */
2784static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
2785 struct drm_dp_sideband_msg_tx *txmsg,
2786 bool up)
2787{
2788 u8 chunk[48];
2789 struct drm_dp_sideband_msg_hdr hdr;
2790 int len, space, idx, tosend;
2791 int ret;
2792
Lyude Pauld308a882020-04-24 14:13:08 -04002793 if (txmsg->state == DRM_DP_SIDEBAND_TX_SENT)
2794 return 0;
2795
Damien Lespiaubf3719c2014-07-14 12:13:18 +01002796 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
2797
Lyude Pauld308a882020-04-24 14:13:08 -04002798 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED)
Dave Airliead7f8a12014-06-05 14:01:32 +10002799 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
Dave Airliead7f8a12014-06-05 14:01:32 +10002800
Lyude Pauld308a882020-04-24 14:13:08 -04002801 /* make hdr from dst mst */
Dave Airliead7f8a12014-06-05 14:01:32 +10002802 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
2803 if (ret < 0)
2804 return ret;
2805
2806 /* amount left to send in this message */
2807 len = txmsg->cur_len - txmsg->cur_offset;
2808
2809 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
2810 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
2811
2812 tosend = min(len, space);
2813 if (len == txmsg->cur_len)
2814 hdr.somt = 1;
2815 if (space >= len)
2816 hdr.eomt = 1;
2817
2818
2819 hdr.msg_len = tosend + 1;
2820 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
2821 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
2822 /* add crc at end */
2823 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
2824 idx += tosend + 1;
2825
2826 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
Rajkumar Subbiah92bd92c2021-07-06 08:30:34 -07002827 if (ret) {
2828 if (drm_debug_enabled(DRM_UT_DP)) {
Jani Nikula6470aac2024-01-16 15:07:29 +02002829 struct drm_printer p = drm_dbg_printer(mgr->dev,
2830 DRM_UT_DP,
2831 DBG_PREFIX);
Lyude Paul2f015ec2019-09-03 16:45:45 -04002832
Rajkumar Subbiah92bd92c2021-07-06 08:30:34 -07002833 drm_printf(&p, "sideband msg failed to send\n");
2834 drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
2835 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002836 return ret;
2837 }
2838
2839 txmsg->cur_offset += tosend;
2840 if (txmsg->cur_offset == txmsg->cur_len) {
2841 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
2842 return 1;
2843 }
2844 return 0;
2845}
2846
Dave Airliead7f8a12014-06-05 14:01:32 +10002847static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
2848{
2849 struct drm_dp_sideband_msg_tx *txmsg;
2850 int ret;
2851
Daniel Vettercd961bb2015-01-28 10:02:23 +01002852 WARN_ON(!mutex_is_locked(&mgr->qlock));
2853
Dave Airliead7f8a12014-06-05 14:01:32 +10002854 /* construct a chunk from the first msg in the tx_msg queue */
Daniel Vettercb021a32016-07-15 21:48:03 +02002855 if (list_empty(&mgr->tx_msg_downq))
Dave Airliead7f8a12014-06-05 14:01:32 +10002856 return;
Dave Airliead7f8a12014-06-05 14:01:32 +10002857
Lyude Pauld308a882020-04-24 14:13:08 -04002858 txmsg = list_first_entry(&mgr->tx_msg_downq,
2859 struct drm_dp_sideband_msg_tx, next);
Dave Airliead7f8a12014-06-05 14:01:32 +10002860 ret = process_single_tx_qlock(mgr, txmsg, false);
Lyude Pauld308a882020-04-24 14:13:08 -04002861 if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002862 drm_dbg_kms(mgr->dev, "failed to send msg in q %d\n", ret);
Dave Airliead7f8a12014-06-05 14:01:32 +10002863 list_del(&txmsg->next);
Dave Airliead7f8a12014-06-05 14:01:32 +10002864 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
Chris Wilson68e989d2017-05-13 11:52:01 +01002865 wake_up_all(&mgr->tx_waitq);
Dave Airliead7f8a12014-06-05 14:01:32 +10002866 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002867}
2868
Dave Airliead7f8a12014-06-05 14:01:32 +10002869static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
2870 struct drm_dp_sideband_msg_tx *txmsg)
2871{
2872 mutex_lock(&mgr->qlock);
2873 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
Lyude Paul2f015ec2019-09-03 16:45:45 -04002874
Jani Nikulaf0a8f532019-10-01 17:06:14 +03002875 if (drm_debug_enabled(DRM_UT_DP)) {
Jani Nikula6470aac2024-01-16 15:07:29 +02002876 struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP,
2877 DBG_PREFIX);
Lyude Paul2f015ec2019-09-03 16:45:45 -04002878
2879 drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
2880 }
2881
Lyude Pauld308a882020-04-24 14:13:08 -04002882 if (list_is_singular(&mgr->tx_msg_downq))
Dave Airliead7f8a12014-06-05 14:01:32 +10002883 process_single_down_tx_qlock(mgr);
2884 mutex_unlock(&mgr->qlock);
2885}
2886
Lyude Paul5950f0b2019-09-03 16:45:39 -04002887static void
Lyude Paul3a08f532021-04-23 14:43:09 -04002888drm_dp_dump_link_address(const struct drm_dp_mst_topology_mgr *mgr,
2889 struct drm_dp_link_address_ack_reply *reply)
Lyude Paul5950f0b2019-09-03 16:45:39 -04002890{
2891 struct drm_dp_link_addr_reply_port *port_reply;
2892 int i;
2893
2894 for (i = 0; i < reply->nports; i++) {
2895 port_reply = &reply->ports[i];
Lyude Paul3a08f532021-04-23 14:43:09 -04002896 drm_dbg_kms(mgr->dev,
2897 "port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n",
2898 i,
2899 port_reply->input_port,
2900 port_reply->peer_device_type,
2901 port_reply->port_number,
2902 port_reply->dpcd_revision,
2903 port_reply->mcs,
2904 port_reply->ddps,
2905 port_reply->legacy_device_plug_status,
2906 port_reply->num_sdp_streams,
2907 port_reply->num_sdp_stream_sinks);
Lyude Paul5950f0b2019-09-03 16:45:39 -04002908 }
2909}
2910
Lyude Paul6f85f732019-06-17 19:57:33 -04002911static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
Dave Airlie68d8c9f2015-09-06 18:53:00 +10002912 struct drm_dp_mst_branch *mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10002913{
Dave Airliead7f8a12014-06-05 14:01:32 +10002914 struct drm_dp_sideband_msg_tx *txmsg;
Lyude Paul37dfdc52019-09-03 16:45:53 -04002915 struct drm_dp_link_address_ack_reply *reply;
Lyude Paul6f85f732019-06-17 19:57:33 -04002916 struct drm_dp_mst_port *port, *tmp;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002917 int i, ret, port_mask = 0;
Lyude Paul6f85f732019-06-17 19:57:33 -04002918 bool changed = false;
Dave Airliead7f8a12014-06-05 14:01:32 +10002919
2920 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2921 if (!txmsg)
Lyude Paul6f85f732019-06-17 19:57:33 -04002922 return -ENOMEM;
Dave Airliead7f8a12014-06-05 14:01:32 +10002923
2924 txmsg->dst = mstb;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002925 build_link_address(txmsg);
Dave Airliead7f8a12014-06-05 14:01:32 +10002926
Dave Airlie68d8c9f2015-09-06 18:53:00 +10002927 mstb->link_address_sent = true;
Dave Airliead7f8a12014-06-05 14:01:32 +10002928 drm_dp_queue_down_tx(mgr, txmsg);
2929
Lyude Paul37dfdc52019-09-03 16:45:53 -04002930 /* FIXME: Actually do some real error handling here */
Dave Airliead7f8a12014-06-05 14:01:32 +10002931 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
Wayne Lind63d8102024-06-26 16:48:23 +08002932 if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002933 drm_err(mgr->dev, "Sending link address failed with %d\n", ret);
Lyude Paul37dfdc52019-09-03 16:45:53 -04002934 goto out;
2935 }
2936 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
Lyude Paul3a08f532021-04-23 14:43:09 -04002937 drm_err(mgr->dev, "link address NAK received\n");
Lyude Paul37dfdc52019-09-03 16:45:53 -04002938 ret = -EIO;
2939 goto out;
Dave Airlie68d8c9f2015-09-06 18:53:00 +10002940 }
Dave Airliead7f8a12014-06-05 14:01:32 +10002941
Lyude Paul37dfdc52019-09-03 16:45:53 -04002942 reply = &txmsg->reply.u.link_addr;
Lyude Paul3a08f532021-04-23 14:43:09 -04002943 drm_dbg_kms(mgr->dev, "link address reply: %d\n", reply->nports);
2944 drm_dp_dump_link_address(mgr, reply);
Lyude Paul37dfdc52019-09-03 16:45:53 -04002945
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002946 ret = drm_dp_check_mstb_guid(mstb, reply->guid);
Lyude Paul94b6ada2020-03-06 18:49:22 -05002947 if (ret) {
2948 char buf[64];
2949
2950 drm_dp_mst_rad_to_str(mstb->rad, mstb->lct, buf, sizeof(buf));
Lyude Paul3a08f532021-04-23 14:43:09 -04002951 drm_err(mgr->dev, "GUID check on %s failed: %d\n", buf, ret);
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002952 goto out;
Lyude Paul94b6ada2020-03-06 18:49:22 -05002953 }
Lyude Paul37dfdc52019-09-03 16:45:53 -04002954
Lyude Paul6f85f732019-06-17 19:57:33 -04002955 for (i = 0; i < reply->nports; i++) {
2956 port_mask |= BIT(reply->ports[i].port_number);
2957 ret = drm_dp_mst_handle_link_address_port(mstb, mgr->dev,
2958 &reply->ports[i]);
2959 if (ret == 1)
2960 changed = true;
2961 else if (ret < 0)
2962 goto out;
2963 }
Lyude Paul37dfdc52019-09-03 16:45:53 -04002964
Lyude Paul6f85f732019-06-17 19:57:33 -04002965 /* Prune any ports that are currently a part of mstb in our in-memory
2966 * topology, but were not seen in this link address. Usually this
2967 * means that they were removed while the topology was out of sync,
2968 * e.g. during suspend/resume
2969 */
2970 mutex_lock(&mgr->lock);
2971 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
2972 if (port_mask & BIT(port->port_num))
2973 continue;
2974
Lyude Paul3a08f532021-04-23 14:43:09 -04002975 drm_dbg_kms(mgr->dev, "port %d was not in link address, removing\n",
2976 port->port_num);
Lyude Paul6f85f732019-06-17 19:57:33 -04002977 list_del(&port->next);
2978 drm_dp_mst_topology_put_port(port);
2979 changed = true;
2980 }
2981 mutex_unlock(&mgr->lock);
Lyude Paul37dfdc52019-09-03 16:45:53 -04002982
2983out:
Wayne Lind63d8102024-06-26 16:48:23 +08002984 if (ret < 0)
Lyude Paul37dfdc52019-09-03 16:45:53 -04002985 mstb->link_address_sent = false;
Dave Airliead7f8a12014-06-05 14:01:32 +10002986 kfree(txmsg);
Lyude Paul6f85f732019-06-17 19:57:33 -04002987 return ret < 0 ? ret : changed;
Dave Airliead7f8a12014-06-05 14:01:32 +10002988}
2989
Chris Wilsona4292e52020-05-16 22:23:30 +01002990static void
2991drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr,
2992 struct drm_dp_mst_branch *mstb)
Sean Paulf7948902019-08-28 20:09:44 -04002993{
2994 struct drm_dp_sideband_msg_tx *txmsg;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01002995 int ret;
Sean Paulf7948902019-08-28 20:09:44 -04002996
2997 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2998 if (!txmsg)
2999 return;
3000
3001 txmsg->dst = mstb;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003002 build_clear_payload_id_table(txmsg);
Sean Paulf7948902019-08-28 20:09:44 -04003003
3004 drm_dp_queue_down_tx(mgr, txmsg);
3005
3006 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3007 if (ret > 0 && txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK)
Lyude Paul3a08f532021-04-23 14:43:09 -04003008 drm_dbg_kms(mgr->dev, "clear payload table id nak received\n");
Sean Paulf7948902019-08-28 20:09:44 -04003009
3010 kfree(txmsg);
3011}
3012
Lyude Paul95b00132019-09-03 16:45:47 -04003013static int
3014drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
3015 struct drm_dp_mst_branch *mstb,
3016 struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10003017{
Lyude Paul95b00132019-09-03 16:45:47 -04003018 struct drm_dp_enum_path_resources_ack_reply *path_res;
Dave Airliead7f8a12014-06-05 14:01:32 +10003019 struct drm_dp_sideband_msg_tx *txmsg;
3020 int ret;
3021
3022 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3023 if (!txmsg)
3024 return -ENOMEM;
3025
3026 txmsg->dst = mstb;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003027 build_enum_path_resources(txmsg, port->port_num);
Dave Airliead7f8a12014-06-05 14:01:32 +10003028
3029 drm_dp_queue_down_tx(mgr, txmsg);
3030
3031 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3032 if (ret > 0) {
Lyude Paul87212b52020-03-06 18:46:21 -05003033 ret = 0;
Lyude Paul95b00132019-09-03 16:45:47 -04003034 path_res = &txmsg->reply.u.path_resources;
3035
Ville Syrjälä45bbda12019-01-22 22:03:00 +02003036 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003037 drm_dbg_kms(mgr->dev, "enum path resources nak received\n");
Ville Syrjälä45bbda12019-01-22 22:03:00 +02003038 } else {
Lyude Paul95b00132019-09-03 16:45:47 -04003039 if (port->port_num != path_res->port_number)
Dave Airliead7f8a12014-06-05 14:01:32 +10003040 DRM_ERROR("got incorrect port in response\n");
Lyude Paul95b00132019-09-03 16:45:47 -04003041
Lyude Paul3a08f532021-04-23 14:43:09 -04003042 drm_dbg_kms(mgr->dev, "enum path resources %d: %d %d\n",
3043 path_res->port_number,
3044 path_res->full_payload_bw_number,
3045 path_res->avail_payload_bw_number);
Lyude Paul87212b52020-03-06 18:46:21 -05003046
3047 /*
3048 * If something changed, make sure we send a
3049 * hotplug
3050 */
3051 if (port->full_pbn != path_res->full_payload_bw_number ||
3052 port->fec_capable != path_res->fec_capable)
3053 ret = 1;
3054
Lyude Paulfcf46382020-03-06 18:46:20 -05003055 port->full_pbn = path_res->full_payload_bw_number;
David Francisa3c2b0f2019-06-06 11:20:10 -04003056 port->fec_capable = path_res->fec_capable;
Dave Airliead7f8a12014-06-05 14:01:32 +10003057 }
3058 }
3059
3060 kfree(txmsg);
Lyude Paul87212b52020-03-06 18:46:21 -05003061 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003062}
3063
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003064static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb)
3065{
3066 if (!mstb->port_parent)
3067 return NULL;
3068
3069 if (mstb->port_parent->mstb != mstb)
3070 return mstb->port_parent;
3071
3072 return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent);
3073}
3074
Lyude Paul56d1c142019-01-10 19:53:30 -05003075/*
3076 * Searches upwards in the topology starting from mstb to try to find the
3077 * closest available parent of mstb that's still connected to the rest of the
3078 * topology. This can be used in order to perform operations like releasing
3079 * payloads, where the branch device which owned the payload may no longer be
3080 * around and thus would require that the payload on the last living relative
3081 * be freed instead.
3082 */
3083static struct drm_dp_mst_branch *
3084drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr,
3085 struct drm_dp_mst_branch *mstb,
3086 int *port_num)
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003087{
3088 struct drm_dp_mst_branch *rmstb = NULL;
3089 struct drm_dp_mst_port *found_port;
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003090
Lyude Paul56d1c142019-01-10 19:53:30 -05003091 mutex_lock(&mgr->lock);
3092 if (!mgr->mst_primary)
3093 goto out;
3094
3095 do {
3096 found_port = drm_dp_get_last_connected_port_to_mstb(mstb);
3097 if (!found_port)
3098 break;
3099
3100 if (drm_dp_mst_topology_try_get_mstb(found_port->parent)) {
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003101 rmstb = found_port->parent;
Lyude Paul56d1c142019-01-10 19:53:30 -05003102 *port_num = found_port->port_num;
3103 } else {
3104 /* Search again, starting from this parent */
3105 mstb = found_port->parent;
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003106 }
Lyude Paul56d1c142019-01-10 19:53:30 -05003107 } while (!rmstb);
3108out:
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003109 mutex_unlock(&mgr->lock);
3110 return rmstb;
3111}
3112
Thierry Reding8fa6a422014-07-21 13:23:57 +02003113static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
3114 struct drm_dp_mst_port *port,
3115 int id,
3116 int pbn)
Dave Airliead7f8a12014-06-05 14:01:32 +10003117{
3118 struct drm_dp_sideband_msg_tx *txmsg;
3119 struct drm_dp_mst_branch *mstb;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003120 int ret, port_num;
Libin Yangef8f9be2015-12-02 14:09:43 +08003121 u8 sinks[DRM_DP_MAX_SDP_STREAMS];
3122 int i;
Dave Airliead7f8a12014-06-05 14:01:32 +10003123
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003124 port_num = port->port_num;
Lyude Pauld0757af2019-01-10 19:53:28 -05003125 mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent);
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003126 if (!mstb) {
Lyude Paulde6d6812019-01-10 19:53:25 -05003127 mstb = drm_dp_get_last_connected_port_and_mstb(mgr,
3128 port->parent,
3129 &port_num);
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003130
Lyude Paulcfe9f902019-01-10 19:53:32 -05003131 if (!mstb)
Mykola Lysenko91a25e42016-01-27 09:39:36 -05003132 return -EINVAL;
3133 }
Dave Airliead7f8a12014-06-05 14:01:32 +10003134
3135 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3136 if (!txmsg) {
3137 ret = -ENOMEM;
3138 goto fail_put;
3139 }
3140
Libin Yangef8f9be2015-12-02 14:09:43 +08003141 for (i = 0; i < port->num_sdp_streams; i++)
3142 sinks[i] = i;
3143
Dave Airliead7f8a12014-06-05 14:01:32 +10003144 txmsg->dst = mstb;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003145 build_allocate_payload(txmsg, port_num,
3146 id,
3147 pbn, port->num_sdp_streams, sinks);
Dave Airliead7f8a12014-06-05 14:01:32 +10003148
3149 drm_dp_queue_down_tx(mgr, txmsg);
3150
Lyude Paul56d1c142019-01-10 19:53:30 -05003151 /*
3152 * FIXME: there is a small chance that between getting the last
3153 * connected mstb and sending the payload message, the last connected
3154 * mstb could also be removed from the topology. In the future, this
3155 * needs to be fixed by restarting the
3156 * drm_dp_get_last_connected_port_and_mstb() search in the event of a
3157 * timeout if the topology is still connected to the system.
3158 */
Dave Airliead7f8a12014-06-05 14:01:32 +10003159 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3160 if (ret > 0) {
Ville Syrjälä45bbda12019-01-22 22:03:00 +02003161 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK)
Dave Airliead7f8a12014-06-05 14:01:32 +10003162 ret = -EINVAL;
Lyude Paulde6d6812019-01-10 19:53:25 -05003163 else
Dave Airliead7f8a12014-06-05 14:01:32 +10003164 ret = 0;
3165 }
3166 kfree(txmsg);
3167fail_put:
Lyude Pauld0757af2019-01-10 19:53:28 -05003168 drm_dp_mst_topology_put_mstb(mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10003169 return ret;
3170}
3171
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003172int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
3173 struct drm_dp_mst_port *port, bool power_up)
3174{
3175 struct drm_dp_sideband_msg_tx *txmsg;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003176 int ret;
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003177
Lyude Pauld0757af2019-01-10 19:53:28 -05003178 port = drm_dp_mst_topology_get_port_validated(mgr, port);
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003179 if (!port)
3180 return -EINVAL;
3181
3182 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3183 if (!txmsg) {
Lyude Pauld0757af2019-01-10 19:53:28 -05003184 drm_dp_mst_topology_put_port(port);
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003185 return -ENOMEM;
3186 }
3187
3188 txmsg->dst = port->parent;
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003189 build_power_updown_phy(txmsg, port->port_num, power_up);
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003190 drm_dp_queue_down_tx(mgr, txmsg);
3191
3192 ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg);
3193 if (ret > 0) {
Ville Syrjälä45bbda12019-01-22 22:03:00 +02003194 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK)
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003195 ret = -EINVAL;
3196 else
3197 ret = 0;
3198 }
3199 kfree(txmsg);
Lyude Pauld0757af2019-01-10 19:53:28 -05003200 drm_dp_mst_topology_put_port(port);
Dhinakaran Pandiyan0bb9c2b2017-09-06 17:14:58 -07003201
3202 return ret;
3203}
3204EXPORT_SYMBOL(drm_dp_send_power_updown_phy);
3205
Sean Paule38c2982020-08-19 10:31:24 -04003206int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr,
3207 struct drm_dp_mst_port *port,
3208 struct drm_dp_query_stream_enc_status_ack_reply *status)
3209{
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003210 struct drm_dp_mst_topology_state *state;
3211 struct drm_dp_mst_atomic_payload *payload;
Sean Paule38c2982020-08-19 10:31:24 -04003212 struct drm_dp_sideband_msg_tx *txmsg;
3213 u8 nonce[7];
Lee Jones0e120f12020-11-16 17:40:33 +00003214 int ret;
Sean Paule38c2982020-08-19 10:31:24 -04003215
3216 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3217 if (!txmsg)
3218 return -ENOMEM;
3219
3220 port = drm_dp_mst_topology_get_port_validated(mgr, port);
3221 if (!port) {
3222 ret = -EINVAL;
3223 goto out_get_port;
3224 }
3225
3226 get_random_bytes(nonce, sizeof(nonce));
3227
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003228 drm_modeset_lock(&mgr->base.lock, NULL);
3229 state = to_drm_dp_mst_topology_state(mgr->base.state);
3230 payload = drm_atomic_get_mst_payload_state(state, port);
3231
Sean Paule38c2982020-08-19 10:31:24 -04003232 /*
3233 * "Source device targets the QUERY_STREAM_ENCRYPTION_STATUS message
3234 * transaction at the MST Branch device directly connected to the
3235 * Source"
3236 */
3237 txmsg->dst = mgr->mst_primary;
3238
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003239 build_query_stream_enc_status(txmsg, payload->vcpi, nonce);
Sean Paule38c2982020-08-19 10:31:24 -04003240
3241 drm_dp_queue_down_tx(mgr, txmsg);
3242
3243 ret = drm_dp_mst_wait_tx_reply(mgr->mst_primary, txmsg);
3244 if (ret < 0) {
3245 goto out;
3246 } else if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
3247 drm_dbg_kms(mgr->dev, "query encryption status nak received\n");
3248 ret = -ENXIO;
3249 goto out;
3250 }
3251
3252 ret = 0;
3253 memcpy(status, &txmsg->reply.u.enc_status, sizeof(*status));
3254
3255out:
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003256 drm_modeset_unlock(&mgr->base.lock);
Sean Paule38c2982020-08-19 10:31:24 -04003257 drm_dp_mst_topology_put_port(port);
3258out_get_port:
3259 kfree(txmsg);
3260 return ret;
3261}
3262EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status);
3263
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003264static int drm_dp_create_payload_at_dfp(struct drm_dp_mst_topology_mgr *mgr,
3265 struct drm_dp_mst_atomic_payload *payload)
Dave Airliead7f8a12014-06-05 14:01:32 +10003266{
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003267 return drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot,
3268 payload->time_slots);
Dave Airliead7f8a12014-06-05 14:01:32 +10003269}
3270
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003271static int drm_dp_create_payload_to_remote(struct drm_dp_mst_topology_mgr *mgr,
3272 struct drm_dp_mst_atomic_payload *payload)
Dave Airliead7f8a12014-06-05 14:01:32 +10003273{
3274 int ret;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003275 struct drm_dp_mst_port *port = drm_dp_mst_topology_get_port_validated(mgr, payload->port);
Suraj Upadhyay948de8422020-07-02 18:53:32 +05303276
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003277 if (!port)
3278 return -EIO;
3279
3280 ret = drm_dp_payload_send_msg(mgr, port, payload->vcpi, payload->pbn);
3281 drm_dp_mst_topology_put_port(port);
Dave Airliead7f8a12014-06-05 14:01:32 +10003282 return ret;
3283}
3284
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003285static void drm_dp_destroy_payload_at_remote_and_dfp(struct drm_dp_mst_topology_mgr *mgr,
3286 struct drm_dp_mst_topology_state *mst_state,
3287 struct drm_dp_mst_atomic_payload *payload)
Dave Airliead7f8a12014-06-05 14:01:32 +10003288{
Lyude Paul3a08f532021-04-23 14:43:09 -04003289 drm_dbg_kms(mgr->dev, "\n");
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003290
Matt Roper1e55a532019-02-01 17:23:26 -08003291 /* it's okay for these to fail */
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003292 if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_REMOTE) {
3293 drm_dp_payload_send_msg(mgr, payload->port, payload->vcpi, 0);
3294 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_DFP;
3295 }
Dave Airliead7f8a12014-06-05 14:01:32 +10003296
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003297 if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_DFP)
3298 drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, 0);
Dave Airliead7f8a12014-06-05 14:01:32 +10003299}
3300
3301/**
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003302 * drm_dp_add_payload_part1() - Execute payload update part 1
3303 * @mgr: Manager to use.
3304 * @mst_state: The MST atomic state
3305 * @payload: The payload to write
Bhawanpreet Lakhad6c6a762021-10-25 18:38:22 -04003306 *
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003307 * Determines the starting time slot for the given payload, and programs the VCPI for this payload
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003308 * into the DPCD of DPRX. After calling this, the driver should generate ACT and payload packets.
Dave Airliead7f8a12014-06-05 14:01:32 +10003309 *
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003310 * Returns: 0 on success, error code on failure.
Dave Airliead7f8a12014-06-05 14:01:32 +10003311 */
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003312int drm_dp_add_payload_part1(struct drm_dp_mst_topology_mgr *mgr,
3313 struct drm_dp_mst_topology_state *mst_state,
3314 struct drm_dp_mst_atomic_payload *payload)
Dave Airliead7f8a12014-06-05 14:01:32 +10003315{
Dave Airliead7f8a12014-06-05 14:01:32 +10003316 struct drm_dp_mst_port *port;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003317 int ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003318
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003319 /* Update mst mgr info */
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003320 if (mgr->payload_count == 0)
3321 mgr->next_start_slot = mst_state->start_slot;
Lyude Paulcfe9f902019-01-10 19:53:32 -05003322
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003323 payload->vc_start_slot = mgr->next_start_slot;
Wayne Lin3769e4c2021-06-16 11:55:01 +08003324
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003325 mgr->payload_count++;
3326 mgr->next_start_slot += payload->time_slots;
Dave Airliead7f8a12014-06-05 14:01:32 +10003327
Imre Deak8bde4442023-09-14 01:32:16 +03003328 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_LOCAL;
3329
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003330 /* Allocate payload to immediate downstream facing port */
3331 port = drm_dp_mst_topology_get_port_validated(mgr, payload->port);
3332 if (!port) {
3333 drm_dbg_kms(mgr->dev,
3334 "VCPI %d for port %p not in topology, not creating a payload to remote\n",
3335 payload->vcpi, payload->port);
Imre Deak8bde4442023-09-14 01:32:16 +03003336 return -EIO;
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003337 }
3338
Imre Deak8bde4442023-09-14 01:32:16 +03003339 ret = drm_dp_create_payload_at_dfp(mgr, payload);
3340 if (ret < 0) {
Imre Deak0663e1d2023-09-14 01:32:17 +03003341 drm_dbg_kms(mgr->dev, "Failed to create MST payload for port %p: %d\n",
3342 payload->port, ret);
Imre Deak8bde4442023-09-14 01:32:16 +03003343 goto put_port;
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003344 }
3345
Imre Deak8bde4442023-09-14 01:32:16 +03003346 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_DFP;
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003347
Imre Deak8bde4442023-09-14 01:32:16 +03003348put_port:
3349 drm_dp_mst_topology_put_port(port);
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003350
3351 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003352}
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003353EXPORT_SYMBOL(drm_dp_add_payload_part1);
Dave Airliead7f8a12014-06-05 14:01:32 +10003354
3355/**
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003356 * drm_dp_remove_payload_part1() - Remove an MST payload along the virtual channel
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003357 * @mgr: Manager to use.
3358 * @mst_state: The MST atomic state
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003359 * @payload: The payload to remove
Dave Airliead7f8a12014-06-05 14:01:32 +10003360 *
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003361 * Removes a payload along the virtual channel if it was successfully allocated.
3362 * After calling this, the driver should set HW to generate ACT and then switch to new
3363 * payload allocation state.
Dave Airliead7f8a12014-06-05 14:01:32 +10003364 */
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003365void drm_dp_remove_payload_part1(struct drm_dp_mst_topology_mgr *mgr,
3366 struct drm_dp_mst_topology_state *mst_state,
3367 struct drm_dp_mst_atomic_payload *payload)
Dave Airliead7f8a12014-06-05 14:01:32 +10003368{
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003369 /* Remove remote payload allocation */
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003370 bool send_remove = false;
3371
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003372 mutex_lock(&mgr->lock);
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003373 send_remove = drm_dp_mst_port_downstream_of_branch(payload->port, mgr->mst_primary);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003374 mutex_unlock(&mgr->lock);
3375
3376 if (send_remove)
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003377 drm_dp_destroy_payload_at_remote_and_dfp(mgr, mst_state, payload);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003378 else
3379 drm_dbg_kms(mgr->dev, "Payload for VCPI %d not in topology, not sending remove\n",
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003380 payload->vcpi);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003381
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003382 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_LOCAL;
3383}
3384EXPORT_SYMBOL(drm_dp_remove_payload_part1);
3385
3386/**
3387 * drm_dp_remove_payload_part2() - Remove an MST payload locally
3388 * @mgr: Manager to use.
3389 * @mst_state: The MST atomic state
3390 * @old_payload: The payload with its old state
3391 * @new_payload: The payload with its latest state
3392 *
3393 * Updates the starting time slots of all other payloads which would have been shifted towards
3394 * the start of the payload ID table as a result of removing a payload. Driver should call this
3395 * function whenever it removes a payload in its HW. It's independent to the result of payload
3396 * allocation/deallocation at branch devices along the virtual channel.
3397 */
3398void drm_dp_remove_payload_part2(struct drm_dp_mst_topology_mgr *mgr,
3399 struct drm_dp_mst_topology_state *mst_state,
3400 const struct drm_dp_mst_atomic_payload *old_payload,
3401 struct drm_dp_mst_atomic_payload *new_payload)
3402{
3403 struct drm_dp_mst_atomic_payload *pos;
3404
3405 /* Remove local payload allocation */
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003406 list_for_each_entry(pos, &mst_state->payloads, next) {
Imre Deake761cc22023-02-06 13:48:54 +02003407 if (pos != new_payload && pos->vc_start_slot > new_payload->vc_start_slot)
3408 pos->vc_start_slot -= old_payload->time_slots;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003409 }
Imre Deake761cc22023-02-06 13:48:54 +02003410 new_payload->vc_start_slot = -1;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003411
3412 mgr->payload_count--;
Imre Deake761cc22023-02-06 13:48:54 +02003413 mgr->next_start_slot -= old_payload->time_slots;
Wayne Lin9b2d0192022-12-28 14:50:43 +08003414
Imre Deake761cc22023-02-06 13:48:54 +02003415 if (new_payload->delete)
3416 drm_dp_mst_put_port_malloc(new_payload->port);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003417
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003418 new_payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_NONE;
3419}
3420EXPORT_SYMBOL(drm_dp_remove_payload_part2);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003421/**
3422 * drm_dp_add_payload_part2() - Execute payload update part 2
3423 * @mgr: Manager to use.
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003424 * @payload: The payload to update
3425 *
3426 * If @payload was successfully assigned a starting time slot by drm_dp_add_payload_part1(), this
3427 * function will send the sideband messages to finish allocating this payload.
3428 *
3429 * Returns: 0 on success, negative error code on failure.
3430 */
3431int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003432 struct drm_dp_mst_atomic_payload *payload)
3433{
Damien Lespiau7389ad42014-07-14 11:53:44 +01003434 int ret = 0;
Suraj Upadhyay948de8422020-07-02 18:53:32 +05303435
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003436 /* Skip failed payloads */
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003437 if (payload->payload_allocation_status != DRM_DP_MST_PAYLOAD_ALLOCATION_DFP) {
Wayne Lin8a0a7b92024-03-07 14:29:57 +08003438 drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n",
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003439 payload->port->connector->name);
3440 return -EIO;
Dave Airliead7f8a12014-06-05 14:01:32 +10003441 }
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003442
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003443 /* Allocate payload to remote end */
3444 ret = drm_dp_create_payload_to_remote(mgr, payload);
3445 if (ret < 0)
Wayne Linae4d2312023-08-07 10:56:37 +08003446 drm_err(mgr->dev, "Step 2 of creating MST payload for %p failed: %d\n",
3447 payload->port, ret);
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08003448 else
3449 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_REMOTE;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003450
3451 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003452}
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003453EXPORT_SYMBOL(drm_dp_add_payload_part2);
Dave Airliead7f8a12014-06-05 14:01:32 +10003454
Dave Airliead7f8a12014-06-05 14:01:32 +10003455static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
3456 struct drm_dp_mst_port *port,
Ville Syrjälä562836a22019-07-23 19:28:01 -04003457 int offset, int size, u8 *bytes)
Dave Airliead7f8a12014-06-05 14:01:32 +10003458{
Ville Syrjälä562836a22019-07-23 19:28:01 -04003459 int ret = 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10003460 struct drm_dp_sideband_msg_tx *txmsg;
Ville Syrjälä562836a22019-07-23 19:28:01 -04003461 struct drm_dp_mst_branch *mstb;
3462
3463 mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent);
3464 if (!mstb)
3465 return -EINVAL;
Dave Airliead7f8a12014-06-05 14:01:32 +10003466
3467 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
Ville Syrjälä562836a22019-07-23 19:28:01 -04003468 if (!txmsg) {
3469 ret = -ENOMEM;
3470 goto fail_put;
3471 }
Dave Airliead7f8a12014-06-05 14:01:32 +10003472
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003473 build_dpcd_read(txmsg, port->port_num, offset, size);
Dave Airliead7f8a12014-06-05 14:01:32 +10003474 txmsg->dst = port->parent;
3475
3476 drm_dp_queue_down_tx(mgr, txmsg);
3477
Ville Syrjälä562836a22019-07-23 19:28:01 -04003478 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3479 if (ret < 0)
3480 goto fail_free;
3481
Ville Syrjälä562836a22019-07-23 19:28:01 -04003482 if (txmsg->reply.reply_type == 1) {
Wayne Lin1e6b8d52022-04-28 20:49:44 +08003483 drm_dbg_kms(mgr->dev, "mstb %p port %d: DPCD read on addr 0x%x for %d bytes NAKed\n",
3484 mstb, port->port_num, offset, size);
Ville Syrjälä562836a22019-07-23 19:28:01 -04003485 ret = -EIO;
3486 goto fail_free;
3487 }
3488
3489 if (txmsg->reply.u.remote_dpcd_read_ack.num_bytes != size) {
3490 ret = -EPROTO;
3491 goto fail_free;
3492 }
3493
3494 ret = min_t(size_t, txmsg->reply.u.remote_dpcd_read_ack.num_bytes,
3495 size);
3496 memcpy(bytes, txmsg->reply.u.remote_dpcd_read_ack.bytes, ret);
3497
3498fail_free:
3499 kfree(txmsg);
3500fail_put:
3501 drm_dp_mst_topology_put_mstb(mstb);
3502
3503 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003504}
Dave Airliead7f8a12014-06-05 14:01:32 +10003505
3506static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
3507 struct drm_dp_mst_port *port,
3508 int offset, int size, u8 *bytes)
3509{
Dave Airliead7f8a12014-06-05 14:01:32 +10003510 int ret;
3511 struct drm_dp_sideband_msg_tx *txmsg;
3512 struct drm_dp_mst_branch *mstb;
3513
Lyude Pauld0757af2019-01-10 19:53:28 -05003514 mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent);
Dave Airliead7f8a12014-06-05 14:01:32 +10003515 if (!mstb)
3516 return -EINVAL;
3517
3518 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3519 if (!txmsg) {
3520 ret = -ENOMEM;
3521 goto fail_put;
3522 }
3523
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003524 build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
Dave Airliead7f8a12014-06-05 14:01:32 +10003525 txmsg->dst = mstb;
3526
3527 drm_dp_queue_down_tx(mgr, txmsg);
3528
3529 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
Lyude Pauldbc05ae2020-04-24 15:07:22 -04003530 if (ret > 0) {
3531 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK)
3532 ret = -EIO;
3533 else
3534 ret = size;
3535 }
Lyude Paul4c0a9b62020-03-06 18:49:21 -05003536
Dave Airliead7f8a12014-06-05 14:01:32 +10003537 kfree(txmsg);
3538fail_put:
Lyude Pauld0757af2019-01-10 19:53:28 -05003539 drm_dp_mst_topology_put_mstb(mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10003540 return ret;
3541}
3542
3543static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
3544{
3545 struct drm_dp_sideband_msg_reply_body reply;
3546
Ville Syrjälä45bbda12019-01-22 22:03:00 +02003547 reply.reply_type = DP_SIDEBAND_REPLY_ACK;
Dave Airliead7f8a12014-06-05 14:01:32 +10003548 reply.req_type = req_type;
3549 drm_dp_encode_sideband_reply(&reply, msg);
3550 return 0;
3551}
3552
3553static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
3554 struct drm_dp_mst_branch *mstb,
Lyude Pauld308a882020-04-24 14:13:08 -04003555 int req_type, bool broadcast)
Dave Airliead7f8a12014-06-05 14:01:32 +10003556{
3557 struct drm_dp_sideband_msg_tx *txmsg;
3558
3559 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3560 if (!txmsg)
3561 return -ENOMEM;
3562
3563 txmsg->dst = mstb;
Dave Airliead7f8a12014-06-05 14:01:32 +10003564 drm_dp_encode_up_ack_reply(txmsg, req_type);
3565
3566 mutex_lock(&mgr->qlock);
Lyude Pauld308a882020-04-24 14:13:08 -04003567 /* construct a chunk from the first msg in the tx_msg queue */
3568 process_single_tx_qlock(mgr, txmsg, true);
Dave Airliead7f8a12014-06-05 14:01:32 +10003569 mutex_unlock(&mgr->qlock);
Mykola Lysenko1f16ee7f2015-12-18 17:14:43 -05003570
3571 kfree(txmsg);
Dave Airliead7f8a12014-06-05 14:01:32 +10003572 return 0;
3573}
3574
Imre Deak83404d52021-01-25 19:36:35 +02003575/**
3576 * drm_dp_get_vc_payload_bw - get the VC payload BW for an MST link
Lyude Paulc869c5f2021-04-23 14:43:05 -04003577 * @mgr: The &drm_dp_mst_topology_mgr to use
Imre Deak83404d52021-01-25 19:36:35 +02003578 * @link_rate: link rate in 10kbits/s units
3579 * @link_lane_count: lane count
3580 *
3581 * Calculate the total bandwidth of a MultiStream Transport link. The returned
3582 * value is in units of PBNs/(timeslots/1 MTP). This value can be used to
3583 * convert the number of PBNs required for a given stream to the number of
3584 * timeslots this stream requires in each MTP.
Imre Deak191dc432023-11-16 15:18:31 +02003585 *
3586 * Returns the BW / timeslot value in 20.12 fixed point format.
Imre Deak83404d52021-01-25 19:36:35 +02003587 */
Imre Deak191dc432023-11-16 15:18:31 +02003588fixed20_12 drm_dp_get_vc_payload_bw(const struct drm_dp_mst_topology_mgr *mgr,
3589 int link_rate, int link_lane_count)
Dave Airliead7f8a12014-06-05 14:01:32 +10003590{
Imre Deakd3899892023-11-17 17:09:27 +02003591 int ch_coding_efficiency =
3592 drm_dp_bw_channel_coding_efficiency(drm_dp_is_uhbr_rate(link_rate));
Imre Deak191dc432023-11-16 15:18:31 +02003593 fixed20_12 ret;
3594
Imre Deak83404d52021-01-25 19:36:35 +02003595 if (link_rate == 0 || link_lane_count == 0)
Lyude Paul3a08f532021-04-23 14:43:09 -04003596 drm_dbg_kms(mgr->dev, "invalid link rate/lane count: (%d / %d)\n",
3597 link_rate, link_lane_count);
Chris Wilsonb853fdb2014-11-12 10:13:37 +00003598
Imre Deakd3899892023-11-17 17:09:27 +02003599 /* See DP v2.0 2.6.4.2, 2.7.6.3 VCPayload_Bandwidth_for_OneTimeSlotPer_MTP_Allocation */
3600 ret.full = DIV_ROUND_DOWN_ULL(mul_u32_u32(link_rate * link_lane_count,
3601 ch_coding_efficiency),
3602 (1000000ULL * 8 * 5400) >> 12);
Imre Deak191dc432023-11-16 15:18:31 +02003603
3604 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10003605}
Imre Deak83404d52021-01-25 19:36:35 +02003606EXPORT_SYMBOL(drm_dp_get_vc_payload_bw);
Dave Airliead7f8a12014-06-05 14:01:32 +10003607
3608/**
Jani Nikula281a2cc2024-03-19 11:12:48 +02003609 * drm_dp_read_mst_cap() - Read the sink's MST mode capability
Lyude Paul4b4659122020-08-26 14:24:45 -04003610 * @aux: The DP AUX channel to use
3611 * @dpcd: A cached copy of the DPCD capabilities for this sink
3612 *
Jani Nikula281a2cc2024-03-19 11:12:48 +02003613 * Returns: enum drm_dp_mst_mode to indicate MST mode capability
Lyude Paul4b4659122020-08-26 14:24:45 -04003614 */
Jani Nikula281a2cc2024-03-19 11:12:48 +02003615enum drm_dp_mst_mode drm_dp_read_mst_cap(struct drm_dp_aux *aux,
3616 const u8 dpcd[DP_RECEIVER_CAP_SIZE])
Lyude Paul4b4659122020-08-26 14:24:45 -04003617{
3618 u8 mstm_cap;
3619
3620 if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_12)
Jani Nikula281a2cc2024-03-19 11:12:48 +02003621 return DRM_DP_SST;
Lyude Paul4b4659122020-08-26 14:24:45 -04003622
3623 if (drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &mstm_cap) != 1)
Jani Nikula281a2cc2024-03-19 11:12:48 +02003624 return DRM_DP_SST;
Lyude Paul4b4659122020-08-26 14:24:45 -04003625
Jani Nikula281a2cc2024-03-19 11:12:48 +02003626 if (mstm_cap & DP_MST_CAP)
3627 return DRM_DP_MST;
3628
3629 if (mstm_cap & DP_SINGLE_STREAM_SIDEBAND_MSG)
3630 return DRM_DP_SST_SIDEBAND_MSG;
3631
3632 return DRM_DP_SST;
Lyude Paul4b4659122020-08-26 14:24:45 -04003633}
3634EXPORT_SYMBOL(drm_dp_read_mst_cap);
3635
3636/**
Dave Airliead7f8a12014-06-05 14:01:32 +10003637 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
3638 * @mgr: manager to set state for
3639 * @mst_state: true to enable MST on this connector - false to disable.
3640 *
3641 * This is called by the driver when it detects an MST capable device plugged
3642 * into a DP MST capable port, or when a DP MST capable device is unplugged.
3643 */
3644int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
3645{
3646 int ret = 0;
3647 struct drm_dp_mst_branch *mstb = NULL;
3648
3649 mutex_lock(&mgr->lock);
3650 if (mst_state == mgr->mst_state)
3651 goto out_unlock;
3652
3653 mgr->mst_state = mst_state;
3654 /* set the device into MST mode */
3655 if (mst_state) {
3656 WARN_ON(mgr->mst_primary);
3657
3658 /* get dpcd info */
Nikola Cornij98025a62021-04-29 18:11:51 -04003659 ret = drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd);
3660 if (ret < 0) {
3661 drm_dbg_kms(mgr->dev, "%s: failed to read DPCD, ret %d\n",
3662 mgr->aux->name, ret);
Dave Airliead7f8a12014-06-05 14:01:32 +10003663 goto out_unlock;
3664 }
3665
Dave Airliead7f8a12014-06-05 14:01:32 +10003666 /* add initial branch device at LCT 1 */
3667 mstb = drm_dp_add_mst_branch_device(1, NULL);
3668 if (mstb == NULL) {
3669 ret = -ENOMEM;
3670 goto out_unlock;
3671 }
3672 mstb->mgr = mgr;
3673
3674 /* give this the main reference */
3675 mgr->mst_primary = mstb;
Lyude Paulebcc0e62019-01-10 19:53:29 -05003676 drm_dp_mst_topology_get_mstb(mgr->mst_primary);
Dave Airliead7f8a12014-06-05 14:01:32 +10003677
Andrey Grodzovskyc175cd12016-01-22 17:07:29 -05003678 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
Lyude Paul3ff4c242020-01-17 17:47:48 -05003679 DP_MST_EN |
3680 DP_UP_REQ_EN |
3681 DP_UPSTREAM_IS_SRC);
José Roberto de Souza7a3cbf52020-01-16 17:58:35 -08003682 if (ret < 0)
Andrey Grodzovskyc175cd12016-01-22 17:07:29 -05003683 goto out_unlock;
Andrey Grodzovskyc175cd12016-01-22 17:07:29 -05003684
Lyude Paul4d07b0b2022-08-17 15:38:46 -04003685 /* Write reset payload */
3686 drm_dp_dpcd_write_payload(mgr, 0, 0, 0x3f);
Dave Airliead7f8a12014-06-05 14:01:32 +10003687
Dave Airliead7f8a12014-06-05 14:01:32 +10003688 queue_work(system_long_wq, &mgr->work);
3689
3690 ret = 0;
3691 } else {
3692 /* disable MST on the device */
3693 mstb = mgr->mst_primary;
3694 mgr->mst_primary = NULL;
3695 /* this can fail if the device is gone */
3696 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
3697 ret = 0;
Sean Paulf7948902019-08-28 20:09:44 -04003698 mgr->payload_id_table_cleared = false;
Imre Deak1d082612022-12-14 20:42:56 +02003699
3700 memset(&mgr->down_rep_recv, 0, sizeof(mgr->down_rep_recv));
3701 memset(&mgr->up_req_recv, 0, sizeof(mgr->up_req_recv));
Dave Airliead7f8a12014-06-05 14:01:32 +10003702 }
3703
3704out_unlock:
3705 mutex_unlock(&mgr->lock);
3706 if (mstb)
Lyude Pauld0757af2019-01-10 19:53:28 -05003707 drm_dp_mst_topology_put_mstb(mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10003708 return ret;
3709
3710}
3711EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
3712
Lyude Paul6f85f732019-06-17 19:57:33 -04003713static void
3714drm_dp_mst_topology_mgr_invalidate_mstb(struct drm_dp_mst_branch *mstb)
3715{
3716 struct drm_dp_mst_port *port;
3717
3718 /* The link address will need to be re-sent on resume */
3719 mstb->link_address_sent = false;
3720
Lyude Paul87212b52020-03-06 18:46:21 -05003721 list_for_each_entry(port, &mstb->ports, next)
Lyude Paul6f85f732019-06-17 19:57:33 -04003722 if (port->mstb)
3723 drm_dp_mst_topology_mgr_invalidate_mstb(port->mstb);
Lyude Paul6f85f732019-06-17 19:57:33 -04003724}
3725
Dave Airliead7f8a12014-06-05 14:01:32 +10003726/**
3727 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
3728 * @mgr: manager to suspend
3729 *
3730 * This function tells the MST device that we can't handle UP messages
3731 * anymore. This should stop it from sending any since we are suspended.
3732 */
3733void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
3734{
3735 mutex_lock(&mgr->lock);
3736 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
3737 DP_MST_EN | DP_UPSTREAM_IS_SRC);
3738 mutex_unlock(&mgr->lock);
Lyude Paul9408cc92019-06-17 16:37:18 -04003739 flush_work(&mgr->up_req_work);
Dave Airlie274d8352015-09-30 10:39:42 +10003740 flush_work(&mgr->work);
Lyude Paul7cb12d42019-02-19 17:41:02 -05003741 flush_work(&mgr->delayed_destroy_work);
Lyude Paul6f85f732019-06-17 19:57:33 -04003742
3743 mutex_lock(&mgr->lock);
3744 if (mgr->mst_state && mgr->mst_primary)
3745 drm_dp_mst_topology_mgr_invalidate_mstb(mgr->mst_primary);
3746 mutex_unlock(&mgr->lock);
Dave Airliead7f8a12014-06-05 14:01:32 +10003747}
3748EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
3749
3750/**
3751 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
3752 * @mgr: manager to resume
Lyude Paul6f85f732019-06-17 19:57:33 -04003753 * @sync: whether or not to perform topology reprobing synchronously
Dave Airliead7f8a12014-06-05 14:01:32 +10003754 *
3755 * This will fetch DPCD and see if the device is still there,
3756 * if it is, it will rewrite the MSTM control bits, and return.
3757 *
Lyude Paul6f85f732019-06-17 19:57:33 -04003758 * If the device fails this returns -1, and the driver should do
Dave Airliead7f8a12014-06-05 14:01:32 +10003759 * a full MST reprobe, in case we were undocked.
Lyude Paul6f85f732019-06-17 19:57:33 -04003760 *
3761 * During system resume (where it is assumed that the driver will be calling
3762 * drm_atomic_helper_resume()) this function should be called beforehand with
3763 * @sync set to true. In contexts like runtime resume where the driver is not
3764 * expected to be calling drm_atomic_helper_resume(), this function should be
3765 * called with @sync set to false in order to avoid deadlocking.
3766 *
3767 * Returns: -1 if the MST topology was removed while we were suspended, 0
3768 * otherwise.
Dave Airliead7f8a12014-06-05 14:01:32 +10003769 */
Lyude Paul6f85f732019-06-17 19:57:33 -04003770int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr,
3771 bool sync)
Dave Airliead7f8a12014-06-05 14:01:32 +10003772{
Lyude Paul79413ed2019-10-09 15:14:59 -04003773 int ret;
3774 u8 guid[16];
Dave Airliead7f8a12014-06-05 14:01:32 +10003775
3776 mutex_lock(&mgr->lock);
Lyude Paul79413ed2019-10-09 15:14:59 -04003777 if (!mgr->mst_primary)
3778 goto out_fail;
Dave Airliead7f8a12014-06-05 14:01:32 +10003779
Imre Deak7a710a82022-06-14 12:45:37 +03003780 if (drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd) < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003781 drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n");
Lyude Paul79413ed2019-10-09 15:14:59 -04003782 goto out_fail;
3783 }
Lyude1652fce2016-04-13 16:50:18 -04003784
Lyude Paul79413ed2019-10-09 15:14:59 -04003785 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
3786 DP_MST_EN |
3787 DP_UP_REQ_EN |
3788 DP_UPSTREAM_IS_SRC);
3789 if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003790 drm_dbg_kms(mgr->dev, "mst write failed - undocked during suspend?\n");
Lyude Paul79413ed2019-10-09 15:14:59 -04003791 goto out_fail;
3792 }
Dave Airliead7f8a12014-06-05 14:01:32 +10003793
Lyude Paul79413ed2019-10-09 15:14:59 -04003794 /* Some hubs forget their guids after they resume */
3795 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16);
3796 if (ret != 16) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003797 drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n");
Lyude Paul79413ed2019-10-09 15:14:59 -04003798 goto out_fail;
3799 }
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003800
3801 ret = drm_dp_check_mstb_guid(mgr->mst_primary, guid);
3802 if (ret) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003803 drm_dbg_kms(mgr->dev, "check mstb failed - undocked during suspend?\n");
Benjamin Gaignardcb897542020-02-05 09:48:42 +01003804 goto out_fail;
3805 }
Lyude1652fce2016-04-13 16:50:18 -04003806
Lyude Paul6f85f732019-06-17 19:57:33 -04003807 /*
3808 * For the final step of resuming the topology, we need to bring the
3809 * state of our in-memory topology back into sync with reality. So,
3810 * restart the probing process as if we're probing a new hub
3811 */
3812 queue_work(system_long_wq, &mgr->work);
Dave Airliead7f8a12014-06-05 14:01:32 +10003813 mutex_unlock(&mgr->lock);
Lyude Paul79413ed2019-10-09 15:14:59 -04003814
Lyude Paul6f85f732019-06-17 19:57:33 -04003815 if (sync) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003816 drm_dbg_kms(mgr->dev,
3817 "Waiting for link probe work to finish re-syncing topology...\n");
Lyude Paul6f85f732019-06-17 19:57:33 -04003818 flush_work(&mgr->work);
3819 }
3820
Lyude Paul79413ed2019-10-09 15:14:59 -04003821 return 0;
3822
3823out_fail:
3824 mutex_unlock(&mgr->lock);
3825 return -1;
Dave Airliead7f8a12014-06-05 14:01:32 +10003826}
3827EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
3828
Lyude Pauld308a882020-04-24 14:13:08 -04003829static bool
3830drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
3831 struct drm_dp_mst_branch **mstb)
Dave Airliead7f8a12014-06-05 14:01:32 +10003832{
3833 int len;
3834 u8 replyblock[32];
Bo YUb37ea8b2020-01-18 16:06:28 +08003835 int replylen, curreply;
Dave Airliead7f8a12014-06-05 14:01:32 +10003836 int ret;
Sean Paul21a729d2020-02-13 16:15:18 -05003837 u8 hdrlen;
3838 struct drm_dp_sideband_msg_hdr hdr;
Lyude Pauld308a882020-04-24 14:13:08 -04003839 struct drm_dp_sideband_msg_rx *msg =
3840 up ? &mgr->up_req_recv : &mgr->down_rep_recv;
Sean Paul21a729d2020-02-13 16:15:18 -05003841 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE :
3842 DP_SIDEBAND_MSG_DOWN_REP_BASE;
3843
Lyude Paulcbfb1b72020-04-06 15:33:52 -04003844 if (!up)
3845 *mstb = NULL;
Dave Airliead7f8a12014-06-05 14:01:32 +10003846
3847 len = min(mgr->max_dpcd_transaction_bytes, 16);
Sean Paul21a729d2020-02-13 16:15:18 -05003848 ret = drm_dp_dpcd_read(mgr->aux, basereg, replyblock, len);
Dave Airliead7f8a12014-06-05 14:01:32 +10003849 if (ret != len) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003850 drm_dbg_kms(mgr->dev, "failed to read DPCD down rep %d %d\n", len, ret);
Imre Deak636c4c32017-07-19 16:46:32 +03003851 return false;
Dave Airliead7f8a12014-06-05 14:01:32 +10003852 }
Sean Paul21a729d2020-02-13 16:15:18 -05003853
Lyude Paul3a08f532021-04-23 14:43:09 -04003854 ret = drm_dp_decode_sideband_msg_hdr(mgr, &hdr, replyblock, len, &hdrlen);
Sean Paul21a729d2020-02-13 16:15:18 -05003855 if (ret == false) {
3856 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16,
3857 1, replyblock, len, false);
Lyude Paul3a08f532021-04-23 14:43:09 -04003858 drm_dbg_kms(mgr->dev, "ERROR: failed header\n");
Sean Paul21a729d2020-02-13 16:15:18 -05003859 return false;
3860 }
3861
Lyude Pauld308a882020-04-24 14:13:08 -04003862 if (!up) {
Sean Paulfbc821c2020-02-13 16:15:19 -05003863 /* Caller is responsible for giving back this reference */
3864 *mstb = drm_dp_get_mst_branch_device(mgr, hdr.lct, hdr.rad);
3865 if (!*mstb) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003866 drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr.lct);
Sean Paulfbc821c2020-02-13 16:15:19 -05003867 return false;
3868 }
Sean Paulfbc821c2020-02-13 16:15:19 -05003869 }
3870
Sean Paul21a729d2020-02-13 16:15:18 -05003871 if (!drm_dp_sideband_msg_set_header(msg, &hdr, hdrlen)) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003872 drm_dbg_kms(mgr->dev, "sideband msg set header failed %d\n", replyblock[0]);
Sean Paul21a729d2020-02-13 16:15:18 -05003873 return false;
3874 }
3875
3876 replylen = min(msg->curchunk_len, (u8)(len - hdrlen));
3877 ret = drm_dp_sideband_append_payload(msg, replyblock + hdrlen, replylen);
Dave Airliead7f8a12014-06-05 14:01:32 +10003878 if (!ret) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003879 drm_dbg_kms(mgr->dev, "sideband msg build failed %d\n", replyblock[0]);
Imre Deak636c4c32017-07-19 16:46:32 +03003880 return false;
Dave Airliead7f8a12014-06-05 14:01:32 +10003881 }
Dave Airliead7f8a12014-06-05 14:01:32 +10003882
Sean Paul21a729d2020-02-13 16:15:18 -05003883 replylen = msg->curchunk_len + msg->curchunk_hdrlen - len;
Dave Airliead7f8a12014-06-05 14:01:32 +10003884 curreply = len;
3885 while (replylen > 0) {
3886 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
3887 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
3888 replyblock, len);
3889 if (ret != len) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003890 drm_dbg_kms(mgr->dev, "failed to read a chunk (len %d, ret %d)\n",
3891 len, ret);
Imre Deak636c4c32017-07-19 16:46:32 +03003892 return false;
Dave Airliead7f8a12014-06-05 14:01:32 +10003893 }
Imre Deak448421b2017-07-19 14:43:28 +03003894
Sean Paul21a729d2020-02-13 16:15:18 -05003895 ret = drm_dp_sideband_append_payload(msg, replyblock, len);
Imre Deak448421b2017-07-19 14:43:28 +03003896 if (!ret) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003897 drm_dbg_kms(mgr->dev, "failed to build sideband msg\n");
Imre Deak636c4c32017-07-19 16:46:32 +03003898 return false;
Imre Deak448421b2017-07-19 14:43:28 +03003899 }
3900
Dave Airliead7f8a12014-06-05 14:01:32 +10003901 curreply += len;
3902 replylen -= len;
3903 }
Imre Deak636c4c32017-07-19 16:46:32 +03003904 return true;
Dave Airliead7f8a12014-06-05 14:01:32 +10003905}
3906
3907static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
3908{
Lyude Paul8b1e5892019-09-03 16:45:51 -04003909 struct drm_dp_sideband_msg_tx *txmsg;
Sean Paulfbc821c2020-02-13 16:15:19 -05003910 struct drm_dp_mst_branch *mstb = NULL;
Lyude Pauld308a882020-04-24 14:13:08 -04003911 struct drm_dp_sideband_msg_rx *msg = &mgr->down_rep_recv;
Dave Airliead7f8a12014-06-05 14:01:32 +10003912
Lyude Pauld308a882020-04-24 14:13:08 -04003913 if (!drm_dp_get_one_sb_msg(mgr, false, &mstb))
Imre Deak1241aed2022-12-14 20:42:57 +02003914 goto out_clear_reply;
Lyude Paul8b1e5892019-09-03 16:45:51 -04003915
Sean Paulfbc821c2020-02-13 16:15:19 -05003916 /* Multi-packet message transmission, don't clear the reply */
3917 if (!msg->have_eomt)
3918 goto out;
Dave Airliead7f8a12014-06-05 14:01:32 +10003919
Lyude Paul8b1e5892019-09-03 16:45:51 -04003920 /* find the message */
Lyude Paul8b1e5892019-09-03 16:45:51 -04003921 mutex_lock(&mgr->qlock);
Lyude Pauld308a882020-04-24 14:13:08 -04003922 txmsg = list_first_entry_or_null(&mgr->tx_msg_downq,
3923 struct drm_dp_sideband_msg_tx, next);
Lyude Paul8b1e5892019-09-03 16:45:51 -04003924 mutex_unlock(&mgr->qlock);
Dave Airliead7f8a12014-06-05 14:01:32 +10003925
Lyude Pauld308a882020-04-24 14:13:08 -04003926 /* Were we actually expecting a response, and from this mstb? */
3927 if (!txmsg || txmsg->dst != mstb) {
Sean Paulfbc821c2020-02-13 16:15:19 -05003928 struct drm_dp_sideband_msg_hdr *hdr;
Suraj Upadhyay948de8422020-07-02 18:53:32 +05303929
Sean Paulfbc821c2020-02-13 16:15:19 -05003930 hdr = &msg->initial_hdr;
Lyude Paul3a08f532021-04-23 14:43:09 -04003931 drm_dbg_kms(mgr->dev, "Got MST reply with no msg %p %d %d %02x %02x\n",
3932 mstb, hdr->seqno, hdr->lct, hdr->rad[0], msg->msg[0]);
Sean Paulfbc821c2020-02-13 16:15:19 -05003933 goto out_clear_reply;
Dave Airliead7f8a12014-06-05 14:01:32 +10003934 }
Lyude Paul8b1e5892019-09-03 16:45:51 -04003935
Lyude Paul3a08f532021-04-23 14:43:09 -04003936 drm_dp_sideband_parse_reply(mgr, msg, &txmsg->reply);
Lyude Paul8b1e5892019-09-03 16:45:51 -04003937
Sean Paulfbc821c2020-02-13 16:15:19 -05003938 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003939 drm_dbg_kms(mgr->dev,
3940 "Got NAK reply: req 0x%02x (%s), reason 0x%02x (%s), nak data 0x%02x\n",
3941 txmsg->reply.req_type,
3942 drm_dp_mst_req_type_str(txmsg->reply.req_type),
3943 txmsg->reply.u.nak.reason,
3944 drm_dp_mst_nak_reason_str(txmsg->reply.u.nak.reason),
3945 txmsg->reply.u.nak.nak_data);
Sean Paulfbc821c2020-02-13 16:15:19 -05003946 }
Lyude Paul8b1e5892019-09-03 16:45:51 -04003947
Sean Paulfbc821c2020-02-13 16:15:19 -05003948 memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
Lyude Paul8b1e5892019-09-03 16:45:51 -04003949 drm_dp_mst_topology_put_mstb(mstb);
3950
3951 mutex_lock(&mgr->qlock);
3952 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
Lyude Pauld308a882020-04-24 14:13:08 -04003953 list_del(&txmsg->next);
Lyude Paul8b1e5892019-09-03 16:45:51 -04003954 mutex_unlock(&mgr->qlock);
3955
3956 wake_up_all(&mgr->tx_waitq);
3957
3958 return 0;
3959
Sean Paulfbc821c2020-02-13 16:15:19 -05003960out_clear_reply:
Lyude Pauld308a882020-04-24 14:13:08 -04003961 memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
Sean Paulfbc821c2020-02-13 16:15:19 -05003962out:
3963 if (mstb)
3964 drm_dp_mst_topology_put_mstb(mstb);
Lyude Paul8b1e5892019-09-03 16:45:51 -04003965
3966 return 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10003967}
3968
Lyude Paul3f9b3f02019-06-17 17:59:29 -04003969static inline bool
Lyude Paul9408cc92019-06-17 16:37:18 -04003970drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
3971 struct drm_dp_pending_up_req *up_req)
3972{
3973 struct drm_dp_mst_branch *mstb = NULL;
3974 struct drm_dp_sideband_msg_req_body *msg = &up_req->msg;
3975 struct drm_dp_sideband_msg_hdr *hdr = &up_req->hdr;
Lyude Paul2482fce2022-08-17 15:38:43 -04003976 bool hotplug = false, dowork = false;
Lyude Paul9408cc92019-06-17 16:37:18 -04003977
3978 if (hdr->broadcast) {
3979 const u8 *guid = NULL;
3980
3981 if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY)
3982 guid = msg->u.conn_stat.guid;
3983 else if (msg->req_type == DP_RESOURCE_STATUS_NOTIFY)
3984 guid = msg->u.resource_stat.guid;
3985
José Roberto de Souza8ccb5bf2020-01-29 15:24:48 -08003986 if (guid)
3987 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid);
Lyude Paul9408cc92019-06-17 16:37:18 -04003988 } else {
3989 mstb = drm_dp_get_mst_branch_device(mgr, hdr->lct, hdr->rad);
3990 }
3991
3992 if (!mstb) {
Lyude Paul3a08f532021-04-23 14:43:09 -04003993 drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr->lct);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04003994 return false;
Lyude Paul9408cc92019-06-17 16:37:18 -04003995 }
3996
3997 /* TODO: Add missing handler for DP_RESOURCE_STATUS_NOTIFY events */
3998 if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
Lyude Paul2482fce2022-08-17 15:38:43 -04003999 dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004000 hotplug = true;
Lyude Paul9408cc92019-06-17 16:37:18 -04004001 }
4002
4003 drm_dp_mst_topology_put_mstb(mstb);
Lyude Paul2482fce2022-08-17 15:38:43 -04004004
4005 if (dowork)
4006 queue_work(system_long_wq, &mgr->work);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004007 return hotplug;
Lyude Paul9408cc92019-06-17 16:37:18 -04004008}
4009
4010static void drm_dp_mst_up_req_work(struct work_struct *work)
4011{
4012 struct drm_dp_mst_topology_mgr *mgr =
4013 container_of(work, struct drm_dp_mst_topology_mgr,
4014 up_req_work);
4015 struct drm_dp_pending_up_req *up_req;
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004016 bool send_hotplug = false;
Lyude Paul9408cc92019-06-17 16:37:18 -04004017
Lyude Paul14692a32019-10-16 16:02:59 -04004018 mutex_lock(&mgr->probe_lock);
Lyude Paul9408cc92019-06-17 16:37:18 -04004019 while (true) {
4020 mutex_lock(&mgr->up_req_lock);
4021 up_req = list_first_entry_or_null(&mgr->up_req_list,
4022 struct drm_dp_pending_up_req,
4023 next);
4024 if (up_req)
4025 list_del(&up_req->next);
4026 mutex_unlock(&mgr->up_req_lock);
4027
4028 if (!up_req)
4029 break;
4030
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004031 send_hotplug |= drm_dp_mst_process_up_req(mgr, up_req);
Lyude Paul9408cc92019-06-17 16:37:18 -04004032 kfree(up_req);
4033 }
Lyude Paul14692a32019-10-16 16:02:59 -04004034 mutex_unlock(&mgr->probe_lock);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004035
4036 if (send_hotplug)
4037 drm_kms_helper_hotplug_event(mgr->dev);
Lyude Paul9408cc92019-06-17 16:37:18 -04004038}
4039
Dave Airliead7f8a12014-06-05 14:01:32 +10004040static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
4041{
Lyude Paul9408cc92019-06-17 16:37:18 -04004042 struct drm_dp_pending_up_req *up_req;
Imre Deak636c4c32017-07-19 16:46:32 +03004043
Lyude Pauld308a882020-04-24 14:13:08 -04004044 if (!drm_dp_get_one_sb_msg(mgr, true, NULL))
Lyude Paula29d8812019-09-03 16:45:50 -04004045 goto out;
Dave Airliead7f8a12014-06-05 14:01:32 +10004046
Lyude Paul60f9ae92019-09-03 16:45:48 -04004047 if (!mgr->up_req_recv.have_eomt)
4048 return 0;
Mykola Lysenkobd934322015-12-18 17:14:42 -05004049
Lyude Paul9408cc92019-06-17 16:37:18 -04004050 up_req = kzalloc(sizeof(*up_req), GFP_KERNEL);
Lyude Paul90876fd2021-03-26 16:38:06 -04004051 if (!up_req)
Lyude Paul9408cc92019-06-17 16:37:18 -04004052 return -ENOMEM;
Lyude Paul90876fd2021-03-26 16:38:06 -04004053
Lyude Paul9408cc92019-06-17 16:37:18 -04004054 INIT_LIST_HEAD(&up_req->next);
Lyude Paul60f9ae92019-09-03 16:45:48 -04004055
Lyude Paul3a08f532021-04-23 14:43:09 -04004056 drm_dp_sideband_parse_req(mgr, &mgr->up_req_recv, &up_req->msg);
Lyude Paul60f9ae92019-09-03 16:45:48 -04004057
Lyude Paul9408cc92019-06-17 16:37:18 -04004058 if (up_req->msg.req_type != DP_CONNECTION_STATUS_NOTIFY &&
4059 up_req->msg.req_type != DP_RESOURCE_STATUS_NOTIFY) {
Lyude Paul3a08f532021-04-23 14:43:09 -04004060 drm_dbg_kms(mgr->dev, "Received unknown up req type, ignoring: %x\n",
4061 up_req->msg.req_type);
Lyude Paul9408cc92019-06-17 16:37:18 -04004062 kfree(up_req);
Lyude Paula29d8812019-09-03 16:45:50 -04004063 goto out;
Lyude Paul60f9ae92019-09-03 16:45:48 -04004064 }
4065
Lyude Paul9408cc92019-06-17 16:37:18 -04004066 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, up_req->msg.req_type,
Lyude Pauld308a882020-04-24 14:13:08 -04004067 false);
Lyude Paul9408cc92019-06-17 16:37:18 -04004068
4069 if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
4070 const struct drm_dp_connection_status_notify *conn_stat =
4071 &up_req->msg.u.conn_stat;
Wayne Linddf98342024-06-26 16:48:24 +08004072 bool handle_csn;
Lyude Paul60f9ae92019-09-03 16:45:48 -04004073
Lyude Paul3a08f532021-04-23 14:43:09 -04004074 drm_dbg_kms(mgr->dev, "Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n",
4075 conn_stat->port_number,
4076 conn_stat->legacy_device_plug_status,
4077 conn_stat->displayport_device_plug_status,
4078 conn_stat->message_capability_status,
4079 conn_stat->input_port,
4080 conn_stat->peer_device_type);
Wayne Linddf98342024-06-26 16:48:24 +08004081
4082 mutex_lock(&mgr->probe_lock);
4083 handle_csn = mgr->mst_primary->link_address_sent;
4084 mutex_unlock(&mgr->probe_lock);
4085
4086 if (!handle_csn) {
4087 drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.");
4088 kfree(up_req);
4089 goto out;
4090 }
Lyude Paul9408cc92019-06-17 16:37:18 -04004091 } else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
4092 const struct drm_dp_resource_status_notify *res_stat =
4093 &up_req->msg.u.resource_stat;
Lyude Paula29d8812019-09-03 16:45:50 -04004094
Lyude Paul3a08f532021-04-23 14:43:09 -04004095 drm_dbg_kms(mgr->dev, "Got RSN: pn: %d avail_pbn %d\n",
4096 res_stat->port_number,
4097 res_stat->available_pbn);
Lyude Paula29d8812019-09-03 16:45:50 -04004098 }
4099
Sean Paulfbc821c2020-02-13 16:15:19 -05004100 up_req->hdr = mgr->up_req_recv.initial_hdr;
Lyude Paul9408cc92019-06-17 16:37:18 -04004101 mutex_lock(&mgr->up_req_lock);
4102 list_add_tail(&up_req->next, &mgr->up_req_list);
4103 mutex_unlock(&mgr->up_req_lock);
4104 queue_work(system_long_wq, &mgr->up_req_work);
4105
Lyude Paula29d8812019-09-03 16:45:50 -04004106out:
Lyude Paul60f9ae92019-09-03 16:45:48 -04004107 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
Lyude Paul60f9ae92019-09-03 16:45:48 -04004108 return 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10004109}
4110
4111/**
Wayne Lin72f1de42023-04-17 17:08:12 +08004112 * drm_dp_mst_hpd_irq_handle_event() - MST hotplug IRQ handle MST event
Dave Airliead7f8a12014-06-05 14:01:32 +10004113 * @mgr: manager to notify irq for.
4114 * @esi: 4 bytes from SINK_COUNT_ESI
Wayne Lin72f1de42023-04-17 17:08:12 +08004115 * @ack: 4 bytes used to ack events starting from SINK_COUNT_ESI
Daniel Vetter295ee852014-07-30 14:23:44 +02004116 * @handled: whether the hpd interrupt was consumed or not
Dave Airliead7f8a12014-06-05 14:01:32 +10004117 *
Wayne Lin72f1de42023-04-17 17:08:12 +08004118 * This should be called from the driver when it detects a HPD IRQ,
Dave Airliead7f8a12014-06-05 14:01:32 +10004119 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
Wayne Lin72f1de42023-04-17 17:08:12 +08004120 * topology manager will process the sideband messages received
4121 * as indicated in the DEVICE_SERVICE_IRQ_VECTOR_ESI0 and set the
4122 * corresponding flags that Driver has to ack the DP receiver later.
4123 *
4124 * Note that driver shall also call
4125 * drm_dp_mst_hpd_irq_send_new_request() if the 'handled' is set
4126 * after calling this function, to try to kick off a new request in
4127 * the queue if the previous message transaction is completed.
4128 *
4129 * See also:
4130 * drm_dp_mst_hpd_irq_send_new_request()
Dave Airliead7f8a12014-06-05 14:01:32 +10004131 */
Wayne Lin72f1de42023-04-17 17:08:12 +08004132int drm_dp_mst_hpd_irq_handle_event(struct drm_dp_mst_topology_mgr *mgr, const u8 *esi,
4133 u8 *ack, bool *handled)
Dave Airliead7f8a12014-06-05 14:01:32 +10004134{
4135 int ret = 0;
4136 int sc;
4137 *handled = false;
Jani Nikulaf199f712022-01-04 20:48:57 +02004138 sc = DP_GET_SINK_COUNT(esi[0]);
Dave Airliead7f8a12014-06-05 14:01:32 +10004139
4140 if (sc != mgr->sink_count) {
4141 mgr->sink_count = sc;
4142 *handled = true;
4143 }
4144
4145 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
4146 ret = drm_dp_mst_handle_down_rep(mgr);
4147 *handled = true;
Wayne Lin72f1de42023-04-17 17:08:12 +08004148 ack[1] |= DP_DOWN_REP_MSG_RDY;
Dave Airliead7f8a12014-06-05 14:01:32 +10004149 }
4150
4151 if (esi[1] & DP_UP_REQ_MSG_RDY) {
4152 ret |= drm_dp_mst_handle_up_req(mgr);
4153 *handled = true;
Wayne Lin72f1de42023-04-17 17:08:12 +08004154 ack[1] |= DP_UP_REQ_MSG_RDY;
Dave Airliead7f8a12014-06-05 14:01:32 +10004155 }
4156
Dave Airliead7f8a12014-06-05 14:01:32 +10004157 return ret;
4158}
Wayne Lin72f1de42023-04-17 17:08:12 +08004159EXPORT_SYMBOL(drm_dp_mst_hpd_irq_handle_event);
Dave Airliead7f8a12014-06-05 14:01:32 +10004160
4161/**
Wayne Lin72f1de42023-04-17 17:08:12 +08004162 * drm_dp_mst_hpd_irq_send_new_request() - MST hotplug IRQ kick off new request
4163 * @mgr: manager to notify irq for.
4164 *
4165 * This should be called from the driver when mst irq event is handled
4166 * and acked. Note that new down request should only be sent when
4167 * previous message transaction is completed. Source is not supposed to generate
4168 * interleaved message transactions.
4169 */
4170void drm_dp_mst_hpd_irq_send_new_request(struct drm_dp_mst_topology_mgr *mgr)
4171{
4172 struct drm_dp_sideband_msg_tx *txmsg;
4173 bool kick = true;
4174
4175 mutex_lock(&mgr->qlock);
4176 txmsg = list_first_entry_or_null(&mgr->tx_msg_downq,
4177 struct drm_dp_sideband_msg_tx, next);
4178 /* If last transaction is not completed yet*/
4179 if (!txmsg ||
4180 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
4181 txmsg->state == DRM_DP_SIDEBAND_TX_SENT)
4182 kick = false;
4183 mutex_unlock(&mgr->qlock);
4184
4185 if (kick)
4186 drm_dp_mst_kick_tx(mgr);
4187}
4188EXPORT_SYMBOL(drm_dp_mst_hpd_irq_send_new_request);
4189/**
Dave Airliead7f8a12014-06-05 14:01:32 +10004190 * drm_dp_mst_detect_port() - get connection status for an MST port
Daniel Vetter132d49d2016-07-15 21:48:04 +02004191 * @connector: DRM connector for this port
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004192 * @ctx: The acquisition context to use for grabbing locks
Dave Airliead7f8a12014-06-05 14:01:32 +10004193 * @mgr: manager for this port
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004194 * @port: pointer to a port
Dave Airliead7f8a12014-06-05 14:01:32 +10004195 *
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004196 * This returns the current connection state for a port.
Dave Airliead7f8a12014-06-05 14:01:32 +10004197 */
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004198int
4199drm_dp_mst_detect_port(struct drm_connector *connector,
4200 struct drm_modeset_acquire_ctx *ctx,
4201 struct drm_dp_mst_topology_mgr *mgr,
4202 struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10004203{
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004204 int ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10004205
Matt Roper1e55a532019-02-01 17:23:26 -08004206 /* we need to search for the port in the mgr in case it's gone */
Lyude Pauld0757af2019-01-10 19:53:28 -05004207 port = drm_dp_mst_topology_get_port_validated(mgr, port);
Dave Airliead7f8a12014-06-05 14:01:32 +10004208 if (!port)
4209 return connector_status_disconnected;
4210
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004211 ret = drm_modeset_lock(&mgr->base.lock, ctx);
4212 if (ret)
4213 goto out;
4214
4215 ret = connector_status_disconnected;
4216
Dave Airliead7f8a12014-06-05 14:01:32 +10004217 if (!port->ddps)
4218 goto out;
4219
4220 switch (port->pdt) {
4221 case DP_PEER_DEVICE_NONE:
Imre Deak873e5bb2021-02-01 14:01:42 +02004222 break;
Dave Airliead7f8a12014-06-05 14:01:32 +10004223 case DP_PEER_DEVICE_MST_BRANCHING:
Wayne Lindb1a0792020-01-17 14:03:50 +08004224 if (!port->mcs)
4225 ret = connector_status_connected;
Dave Airliead7f8a12014-06-05 14:01:32 +10004226 break;
4227
4228 case DP_PEER_DEVICE_SST_SINK:
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004229 ret = connector_status_connected;
Dave Airlie8ae22cb2016-02-17 11:36:38 +10004230 /* for logical ports - cache the EDID */
Imre Deakca5d9d72024-04-17 01:10:07 +03004231 if (drm_dp_mst_port_is_logical(port) && !port->cached_edid)
Jani Nikulac1c90422023-05-30 12:08:24 +03004232 port->cached_edid = drm_edid_read_ddc(connector, &port->aux.ddc);
Dave Airliead7f8a12014-06-05 14:01:32 +10004233 break;
4234 case DP_PEER_DEVICE_DP_LEGACY_CONV:
4235 if (port->ldps)
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004236 ret = connector_status_connected;
Dave Airliead7f8a12014-06-05 14:01:32 +10004237 break;
4238 }
4239out:
Lyude Pauld0757af2019-01-10 19:53:28 -05004240 drm_dp_mst_topology_put_port(port);
Lyude Paul3f9b3f02019-06-17 17:59:29 -04004241 return ret;
Dave Airliead7f8a12014-06-05 14:01:32 +10004242}
4243EXPORT_SYMBOL(drm_dp_mst_detect_port);
4244
4245/**
Jani Nikulac1c90422023-05-30 12:08:24 +03004246 * drm_dp_mst_edid_read() - get EDID for an MST port
Dave Airliead7f8a12014-06-05 14:01:32 +10004247 * @connector: toplevel connector to get EDID for
4248 * @mgr: manager for this port
4249 * @port: unverified pointer to a port.
4250 *
4251 * This returns an EDID for the port connected to a connector,
4252 * It validates the pointer still exists so the caller doesn't require a
4253 * reference.
4254 */
Jani Nikulac1c90422023-05-30 12:08:24 +03004255const struct drm_edid *drm_dp_mst_edid_read(struct drm_connector *connector,
4256 struct drm_dp_mst_topology_mgr *mgr,
4257 struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10004258{
Jani Nikulac1c90422023-05-30 12:08:24 +03004259 const struct drm_edid *drm_edid;
Dave Airliead7f8a12014-06-05 14:01:32 +10004260
Matt Roper1e55a532019-02-01 17:23:26 -08004261 /* we need to search for the port in the mgr in case it's gone */
Lyude Pauld0757af2019-01-10 19:53:28 -05004262 port = drm_dp_mst_topology_get_port_validated(mgr, port);
Dave Airliead7f8a12014-06-05 14:01:32 +10004263 if (!port)
4264 return NULL;
4265
Dave Airliec6a0aed2014-10-20 16:28:02 +10004266 if (port->cached_edid)
Jani Nikulac1c90422023-05-30 12:08:24 +03004267 drm_edid = drm_edid_dup(port->cached_edid);
4268 else
4269 drm_edid = drm_edid_read_ddc(connector, &port->aux.ddc);
Jani Nikula3d35ddf2023-05-30 12:08:14 +03004270
Lyude Pauld0757af2019-01-10 19:53:28 -05004271 drm_dp_mst_topology_put_port(port);
Jani Nikulac1c90422023-05-30 12:08:24 +03004272
4273 return drm_edid;
4274}
4275EXPORT_SYMBOL(drm_dp_mst_edid_read);
4276
4277/**
4278 * drm_dp_mst_get_edid() - get EDID for an MST port
4279 * @connector: toplevel connector to get EDID for
4280 * @mgr: manager for this port
4281 * @port: unverified pointer to a port.
4282 *
4283 * This function is deprecated; please use drm_dp_mst_edid_read() instead.
4284 *
4285 * This returns an EDID for the port connected to a connector,
4286 * It validates the pointer still exists so the caller doesn't require a
4287 * reference.
4288 */
4289struct edid *drm_dp_mst_get_edid(struct drm_connector *connector,
4290 struct drm_dp_mst_topology_mgr *mgr,
4291 struct drm_dp_mst_port *port)
4292{
4293 const struct drm_edid *drm_edid;
4294 struct edid *edid;
4295
4296 drm_edid = drm_dp_mst_edid_read(connector, mgr, port);
4297
4298 edid = drm_edid_duplicate(drm_edid_raw(drm_edid));
4299
4300 drm_edid_free(drm_edid);
4301
Dave Airliead7f8a12014-06-05 14:01:32 +10004302 return edid;
4303}
4304EXPORT_SYMBOL(drm_dp_mst_get_edid);
4305
4306/**
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004307 * drm_dp_atomic_find_time_slots() - Find and add time slots to the state
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004308 * @state: global atomic state
4309 * @mgr: MST topology manager for the port
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004310 * @port: port to find time slots for
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004311 * @pbn: bandwidth required for the mode in PBN
4312 *
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004313 * Allocates time slots to @port, replacing any previous time slot allocations it may
4314 * have had. Any atomic drivers which support MST must call this function in
4315 * their &drm_encoder_helper_funcs.atomic_check() callback unconditionally to
4316 * change the current time slot allocation for the new state, and ensure the MST
4317 * atomic state is added whenever the state of payloads in the topology changes.
Lyude Pauleceae142019-01-10 19:53:41 -05004318 *
4319 * Allocations set by this function are not checked against the bandwidth
4320 * restraints of @mgr until the driver calls drm_dp_mst_atomic_check().
4321 *
4322 * Additionally, it is OK to call this function multiple times on the same
4323 * @port as needed. It is not OK however, to call this function and
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004324 * drm_dp_atomic_release_time_slots() in the same atomic check phase.
Lyude Pauleceae142019-01-10 19:53:41 -05004325 *
4326 * See also:
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004327 * drm_dp_atomic_release_time_slots()
Lyude Pauleceae142019-01-10 19:53:41 -05004328 * drm_dp_mst_atomic_check()
4329 *
4330 * Returns:
4331 * Total slots in the atomic state assigned for this port, or a negative error
4332 * code if the port no longer exists
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004333 */
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004334int drm_dp_atomic_find_time_slots(struct drm_atomic_state *state,
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004335 struct drm_dp_mst_topology_mgr *mgr,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004336 struct drm_dp_mst_port *port, int pbn)
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004337{
4338 struct drm_dp_mst_topology_state *topology_state;
Lyude Paul0b4e4772022-08-17 15:38:36 -04004339 struct drm_dp_mst_atomic_payload *payload = NULL;
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004340 struct drm_connector_state *conn_state;
Lyude Paul0b4e4772022-08-17 15:38:36 -04004341 int prev_slots = 0, prev_bw = 0, req_slots;
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004342
4343 topology_state = drm_atomic_get_mst_topology_state(state, mgr);
Ville Syrjälä56a91c42017-07-12 18:51:00 +03004344 if (IS_ERR(topology_state))
4345 return PTR_ERR(topology_state);
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004346
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004347 conn_state = drm_atomic_get_new_connector_state(state, port->connector);
4348 topology_state->pending_crtc_mask |= drm_crtc_mask(conn_state->crtc);
4349
Lyude Pauleceae142019-01-10 19:53:41 -05004350 /* Find the current allocation for this port, if any */
Lyude Paul0b4e4772022-08-17 15:38:36 -04004351 payload = drm_atomic_get_mst_payload_state(topology_state, port);
4352 if (payload) {
4353 prev_slots = payload->time_slots;
4354 prev_bw = payload->pbn;
Lyude Pauleceae142019-01-10 19:53:41 -05004355
Lyude Paul0b4e4772022-08-17 15:38:36 -04004356 /*
4357 * This should never happen, unless the driver tries
4358 * releasing and allocating the same timeslot allocation,
4359 * which is an error
4360 */
Lyude Paul6366fc72022-08-17 15:38:44 -04004361 if (drm_WARN_ON(mgr->dev, payload->delete)) {
Lyude Paul0b4e4772022-08-17 15:38:36 -04004362 drm_err(mgr->dev,
4363 "cannot allocate and release time slots on [MST PORT:%p] in the same state\n",
4364 port);
4365 return -EINVAL;
Lyude Pauleceae142019-01-10 19:53:41 -05004366 }
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004367 }
4368
Imre Deakd3899892023-11-17 17:09:27 +02004369 req_slots = DIV_ROUND_UP(dfixed_const(pbn), topology_state->pbn_div.full);
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004370
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004371 drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] TU %d -> %d\n",
Lyude Paul3a08f532021-04-23 14:43:09 -04004372 port->connector->base.id, port->connector->name,
4373 port, prev_slots, req_slots);
4374 drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] PBN %d -> %d\n",
4375 port->connector->base.id, port->connector->name,
4376 port, prev_bw, pbn);
Lyude Pauleceae142019-01-10 19:53:41 -05004377
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004378 /* Add the new allocation to the state, note the VCPI isn't assigned until the end */
Lyude Paul48b6b372022-08-17 15:38:32 -04004379 if (!payload) {
4380 payload = kzalloc(sizeof(*payload), GFP_KERNEL);
4381 if (!payload)
Lyude Paula3d15c42019-02-01 19:20:02 -05004382 return -ENOMEM;
Lyude Pauleceae142019-01-10 19:53:41 -05004383
4384 drm_dp_mst_get_port_malloc(port);
Lyude Paul48b6b372022-08-17 15:38:32 -04004385 payload->port = port;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004386 payload->vc_start_slot = -1;
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004387 payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_NONE;
Lyude Paul48b6b372022-08-17 15:38:32 -04004388 list_add(&payload->next, &topology_state->payloads);
Lyude Pauleceae142019-01-10 19:53:41 -05004389 }
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004390 payload->time_slots = req_slots;
Lyude Paul48b6b372022-08-17 15:38:32 -04004391 payload->pbn = pbn;
Lyude Pauleceae142019-01-10 19:53:41 -05004392
Wambui Karugaddd9b542019-10-19 10:18:40 +03004393 return req_slots;
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004394}
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004395EXPORT_SYMBOL(drm_dp_atomic_find_time_slots);
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004396
4397/**
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004398 * drm_dp_atomic_release_time_slots() - Release allocated time slots
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004399 * @state: global atomic state
4400 * @mgr: MST topology manager for the port
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004401 * @port: The port to release the time slots from
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004402 *
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004403 * Releases any time slots that have been allocated to a port in the atomic
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004404 * state. Any atomic drivers which support MST must call this function
4405 * unconditionally in their &drm_connector_helper_funcs.atomic_check() callback.
4406 * This helper will check whether time slots would be released by the new state and
4407 * respond accordingly, along with ensuring the MST state is always added to the
4408 * atomic state whenever a new state would modify the state of payloads on the
4409 * topology.
Lyude Pauleceae142019-01-10 19:53:41 -05004410 *
4411 * It is OK to call this even if @port has been removed from the system.
4412 * Additionally, it is OK to call this function multiple times on the same
4413 * @port as needed. It is not OK however, to call this function and
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004414 * drm_dp_atomic_find_time_slots() on the same @port in a single atomic check
Lyude Pauleceae142019-01-10 19:53:41 -05004415 * phase.
4416 *
4417 * See also:
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004418 * drm_dp_atomic_find_time_slots()
Lyude Pauleceae142019-01-10 19:53:41 -05004419 * drm_dp_mst_atomic_check()
4420 *
4421 * Returns:
Lyude Paul946c7012022-08-17 15:38:34 -04004422 * 0 on success, negative error code otherwise
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004423 */
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004424int drm_dp_atomic_release_time_slots(struct drm_atomic_state *state,
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004425 struct drm_dp_mst_topology_mgr *mgr,
Lyude Pauleceae142019-01-10 19:53:41 -05004426 struct drm_dp_mst_port *port)
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004427{
4428 struct drm_dp_mst_topology_state *topology_state;
Lyude Paul0b4e4772022-08-17 15:38:36 -04004429 struct drm_dp_mst_atomic_payload *payload;
Lyude Paulffac9722022-08-17 15:38:38 -04004430 struct drm_connector_state *old_conn_state, *new_conn_state;
Lyude Paul083351e2022-08-17 15:38:39 -04004431 bool update_payload = true;
Lyude Paulffac9722022-08-17 15:38:38 -04004432
4433 old_conn_state = drm_atomic_get_old_connector_state(state, port->connector);
4434 if (!old_conn_state->crtc)
4435 return 0;
4436
4437 /* If the CRTC isn't disabled by this state, don't release it's payload */
4438 new_conn_state = drm_atomic_get_new_connector_state(state, port->connector);
4439 if (new_conn_state->crtc) {
4440 struct drm_crtc_state *crtc_state =
4441 drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);
4442
Lyude Paul083351e2022-08-17 15:38:39 -04004443 /* No modeset means no payload changes, so it's safe to not pull in the MST state */
4444 if (!crtc_state || !drm_atomic_crtc_needs_modeset(crtc_state))
Lyude Paulffac9722022-08-17 15:38:38 -04004445 return 0;
Lyude Paul083351e2022-08-17 15:38:39 -04004446
4447 if (!crtc_state->mode_changed && !crtc_state->connectors_changed)
4448 update_payload = false;
Lyude Paulffac9722022-08-17 15:38:38 -04004449 }
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004450
4451 topology_state = drm_atomic_get_mst_topology_state(state, mgr);
Ville Syrjälä56a91c42017-07-12 18:51:00 +03004452 if (IS_ERR(topology_state))
4453 return PTR_ERR(topology_state);
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004454
Lyude Paulffac9722022-08-17 15:38:38 -04004455 topology_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc);
Lyude Paul083351e2022-08-17 15:38:39 -04004456 if (!update_payload)
4457 return 0;
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004458
Lyude Paul0b4e4772022-08-17 15:38:36 -04004459 payload = drm_atomic_get_mst_payload_state(topology_state, port);
4460 if (WARN_ON(!payload)) {
Lyude Paul48b6b372022-08-17 15:38:32 -04004461 drm_err(mgr->dev, "No payload for [MST PORT:%p] found in mst state %p\n",
Lyude Paul3a08f532021-04-23 14:43:09 -04004462 port, &topology_state->base);
Lyude Pauleceae142019-01-10 19:53:41 -05004463 return -EINVAL;
4464 }
4465
Imre Deak5d832b62022-09-07 17:25:42 +03004466 if (new_conn_state->crtc)
4467 return 0;
4468
Lyude Paul0b4e4772022-08-17 15:38:36 -04004469 drm_dbg_atomic(mgr->dev, "[MST PORT:%p] TU %d -> 0\n", port, payload->time_slots);
Lyude Paul6366fc72022-08-17 15:38:44 -04004470 if (!payload->delete) {
Lyude Paul0b4e4772022-08-17 15:38:36 -04004471 payload->pbn = 0;
Lyude Paul6366fc72022-08-17 15:38:44 -04004472 payload->delete = true;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004473 topology_state->payload_mask &= ~BIT(payload->vcpi - 1);
Lyude Pauleceae142019-01-10 19:53:41 -05004474 }
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004475
4476 return 0;
4477}
Lyude Pauldf78f7f2022-08-17 15:38:33 -04004478EXPORT_SYMBOL(drm_dp_atomic_release_time_slots);
Pandiyan, Dhinakaranedb1ed12017-04-20 22:51:32 -07004479
4480/**
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004481 * drm_dp_mst_atomic_setup_commit() - setup_commit hook for MST helpers
4482 * @state: global atomic state
4483 *
4484 * This function saves all of the &drm_crtc_commit structs in an atomic state that touch any CRTCs
4485 * currently assigned to an MST topology. Drivers must call this hook from their
4486 * &drm_mode_config_helper_funcs.atomic_commit_setup hook.
4487 *
4488 * Returns:
4489 * 0 if all CRTC commits were retrieved successfully, negative error code otherwise
4490 */
4491int drm_dp_mst_atomic_setup_commit(struct drm_atomic_state *state)
4492{
4493 struct drm_dp_mst_topology_mgr *mgr;
4494 struct drm_dp_mst_topology_state *mst_state;
4495 struct drm_crtc *crtc;
4496 struct drm_crtc_state *crtc_state;
4497 int i, j, commit_idx, num_commit_deps;
4498
4499 for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) {
4500 if (!mst_state->pending_crtc_mask)
4501 continue;
4502
4503 num_commit_deps = hweight32(mst_state->pending_crtc_mask);
4504 mst_state->commit_deps = kmalloc_array(num_commit_deps,
4505 sizeof(*mst_state->commit_deps), GFP_KERNEL);
4506 if (!mst_state->commit_deps)
4507 return -ENOMEM;
4508 mst_state->num_commit_deps = num_commit_deps;
4509
4510 commit_idx = 0;
4511 for_each_new_crtc_in_state(state, crtc, crtc_state, j) {
4512 if (mst_state->pending_crtc_mask & drm_crtc_mask(crtc)) {
4513 mst_state->commit_deps[commit_idx++] =
4514 drm_crtc_commit_get(crtc_state->commit);
4515 }
4516 }
4517 }
4518
4519 return 0;
4520}
4521EXPORT_SYMBOL(drm_dp_mst_atomic_setup_commit);
4522
4523/**
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004524 * drm_dp_mst_atomic_wait_for_dependencies() - Wait for all pending commits on MST topologies,
4525 * prepare new MST state for commit
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004526 * @state: global atomic state
4527 *
4528 * Goes through any MST topologies in this atomic state, and waits for any pending commits which
4529 * touched CRTCs that were/are on an MST topology to be programmed to hardware and flipped to before
4530 * returning. This is to prevent multiple non-blocking commits affecting an MST topology from racing
4531 * with eachother by forcing them to be executed sequentially in situations where the only resources
4532 * the modeset objects in these commits share are an MST topology.
4533 *
4534 * This function also prepares the new MST state for commit by performing some state preparation
4535 * which can't be done until this point, such as reading back the final VC start slots (which are
4536 * determined at commit-time) from the previous state.
4537 *
4538 * All MST drivers must call this function after calling drm_atomic_helper_wait_for_dependencies(),
4539 * or whatever their equivalent of that is.
4540 */
4541void drm_dp_mst_atomic_wait_for_dependencies(struct drm_atomic_state *state)
4542{
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004543 struct drm_dp_mst_topology_state *old_mst_state, *new_mst_state;
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004544 struct drm_dp_mst_topology_mgr *mgr;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004545 struct drm_dp_mst_atomic_payload *old_payload, *new_payload;
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004546 int i, j, ret;
4547
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004548 for_each_oldnew_mst_mgr_in_state(state, mgr, old_mst_state, new_mst_state, i) {
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004549 for (j = 0; j < old_mst_state->num_commit_deps; j++) {
4550 ret = drm_crtc_commit_wait(old_mst_state->commit_deps[j]);
4551 if (ret < 0)
4552 drm_err(state->dev, "Failed to wait for %s: %d\n",
4553 old_mst_state->commit_deps[j]->crtc->name, ret);
4554 }
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004555
4556 /* Now that previous state is committed, it's safe to copy over the start slot
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004557 * and allocation status assignments
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004558 */
4559 list_for_each_entry(old_payload, &old_mst_state->payloads, next) {
4560 if (old_payload->delete)
4561 continue;
4562
4563 new_payload = drm_atomic_get_mst_payload_state(new_mst_state,
4564 old_payload->port);
4565 new_payload->vc_start_slot = old_payload->vc_start_slot;
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004566 new_payload->payload_allocation_status =
4567 old_payload->payload_allocation_status;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004568 }
Lyude Paula5c2c0d2022-08-17 15:38:37 -04004569 }
4570}
4571EXPORT_SYMBOL(drm_dp_mst_atomic_wait_for_dependencies);
4572
4573/**
Lyude Paula76eb422022-08-17 15:38:42 -04004574 * drm_dp_mst_root_conn_atomic_check() - Serialize CRTC commits on MST-capable connectors operating
4575 * in SST mode
4576 * @new_conn_state: The new connector state of the &drm_connector
4577 * @mgr: The MST topology manager for the &drm_connector
4578 *
4579 * Since MST uses fake &drm_encoder structs, the generic atomic modesetting code isn't able to
4580 * serialize non-blocking commits happening on the real DP connector of an MST topology switching
4581 * into/away from MST mode - as the CRTC on the real DP connector and the CRTCs on the connector's
4582 * MST topology will never share the same &drm_encoder.
4583 *
4584 * This function takes care of this serialization issue, by checking a root MST connector's atomic
4585 * state to determine if it is about to have a modeset - and then pulling in the MST topology state
4586 * if so, along with adding any relevant CRTCs to &drm_dp_mst_topology_state.pending_crtc_mask.
4587 *
4588 * Drivers implementing MST must call this function from the
4589 * &drm_connector_helper_funcs.atomic_check hook of any physical DP &drm_connector capable of
4590 * driving MST sinks.
4591 *
4592 * Returns:
4593 * 0 on success, negative error code otherwise
4594 */
4595int drm_dp_mst_root_conn_atomic_check(struct drm_connector_state *new_conn_state,
4596 struct drm_dp_mst_topology_mgr *mgr)
4597{
4598 struct drm_atomic_state *state = new_conn_state->state;
4599 struct drm_connector_state *old_conn_state =
4600 drm_atomic_get_old_connector_state(state, new_conn_state->connector);
4601 struct drm_crtc_state *crtc_state;
4602 struct drm_dp_mst_topology_state *mst_state = NULL;
4603
4604 if (new_conn_state->crtc) {
4605 crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);
4606 if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) {
4607 mst_state = drm_atomic_get_mst_topology_state(state, mgr);
4608 if (IS_ERR(mst_state))
4609 return PTR_ERR(mst_state);
4610
4611 mst_state->pending_crtc_mask |= drm_crtc_mask(new_conn_state->crtc);
4612 }
4613 }
4614
4615 if (old_conn_state->crtc) {
4616 crtc_state = drm_atomic_get_new_crtc_state(state, old_conn_state->crtc);
4617 if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) {
4618 if (!mst_state) {
4619 mst_state = drm_atomic_get_mst_topology_state(state, mgr);
4620 if (IS_ERR(mst_state))
4621 return PTR_ERR(mst_state);
4622 }
4623
4624 mst_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc);
4625 }
4626 }
4627
4628 return 0;
4629}
4630EXPORT_SYMBOL(drm_dp_mst_root_conn_atomic_check);
4631
4632/**
Bhawanpreet Lakhad6c6a762021-10-25 18:38:22 -04004633 * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format
4634 * @mst_state: mst_state to update
4635 * @link_encoding_cap: the ecoding format on the link
4636 */
4637void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap)
4638{
4639 if (link_encoding_cap == DP_CAP_ANSI_128B132B) {
4640 mst_state->total_avail_slots = 64;
4641 mst_state->start_slot = 0;
4642 } else {
4643 mst_state->total_avail_slots = 63;
4644 mst_state->start_slot = 1;
4645 }
4646
4647 DRM_DEBUG_KMS("%s encoding format on mst_state 0x%p\n",
4648 (link_encoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b",
4649 mst_state);
4650}
4651EXPORT_SYMBOL(drm_dp_mst_update_slots);
4652
Dave Airliead7f8a12014-06-05 14:01:32 +10004653static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004654 int id, u8 start_slot, u8 num_slots)
Dave Airliead7f8a12014-06-05 14:01:32 +10004655{
4656 u8 payload_alloc[3], status;
4657 int ret;
4658 int retries = 0;
4659
4660 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
4661 DP_PAYLOAD_TABLE_UPDATED);
4662
4663 payload_alloc[0] = id;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004664 payload_alloc[1] = start_slot;
4665 payload_alloc[2] = num_slots;
Dave Airliead7f8a12014-06-05 14:01:32 +10004666
4667 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
4668 if (ret != 3) {
Lyude Paul3a08f532021-04-23 14:43:09 -04004669 drm_dbg_kms(mgr->dev, "failed to write payload allocation %d\n", ret);
Dave Airliead7f8a12014-06-05 14:01:32 +10004670 goto fail;
4671 }
4672
4673retry:
4674 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
4675 if (ret < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04004676 drm_dbg_kms(mgr->dev, "failed to read payload table status %d\n", ret);
Dave Airliead7f8a12014-06-05 14:01:32 +10004677 goto fail;
4678 }
4679
4680 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
4681 retries++;
4682 if (retries < 20) {
4683 usleep_range(10000, 20000);
4684 goto retry;
4685 }
Lyude Paul3a08f532021-04-23 14:43:09 -04004686 drm_dbg_kms(mgr->dev, "status not set after read payload table status %d\n",
4687 status);
Dave Airliead7f8a12014-06-05 14:01:32 +10004688 ret = -EINVAL;
4689 goto fail;
4690 }
4691 ret = 0;
4692fail:
4693 return ret;
4694}
4695
Lyude Paul873a95e2020-04-03 15:47:15 -04004696static int do_get_act_status(struct drm_dp_aux *aux)
4697{
4698 int ret;
4699 u8 status;
4700
4701 ret = drm_dp_dpcd_readb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
4702 if (ret < 0)
4703 return ret;
4704
4705 return status;
4706}
Dave Airliead7f8a12014-06-05 14:01:32 +10004707
4708/**
Lyude Paul17e03aa2020-04-03 14:11:46 -04004709 * drm_dp_check_act_status() - Polls for ACT handled status.
Dave Airliead7f8a12014-06-05 14:01:32 +10004710 * @mgr: manager to use
4711 *
Lyude Paul17e03aa2020-04-03 14:11:46 -04004712 * Tries waiting for the MST hub to finish updating it's payload table by
Lyude Paul873a95e2020-04-03 15:47:15 -04004713 * polling for the ACT handled bit for up to 3 seconds (yes-some hubs really
4714 * take that long).
Lyude Paul17e03aa2020-04-03 14:11:46 -04004715 *
4716 * Returns:
4717 * 0 if the ACT was handled in time, negative error code on failure.
Dave Airliead7f8a12014-06-05 14:01:32 +10004718 */
4719int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
4720{
Lyude Paul873a95e2020-04-03 15:47:15 -04004721 /*
4722 * There doesn't seem to be any recommended retry count or timeout in
4723 * the MST specification. Since some hubs have been observed to take
4724 * over 1 second to update their payload allocations under certain
4725 * conditions, we use a rather large timeout value.
4726 */
4727 const int timeout_ms = 3000;
4728 int ret, status;
Dave Airliead7f8a12014-06-05 14:01:32 +10004729
Lyude Paul873a95e2020-04-03 15:47:15 -04004730 ret = readx_poll_timeout(do_get_act_status, mgr->aux, status,
4731 status & DP_PAYLOAD_ACT_HANDLED || status < 0,
4732 200, timeout_ms * USEC_PER_MSEC);
4733 if (ret < 0 && status >= 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04004734 drm_err(mgr->dev, "Failed to get ACT after %dms, last status: %02x\n",
4735 timeout_ms, status);
Lyude Paula5cb5fa2020-04-03 14:08:32 -04004736 return -EINVAL;
Lyude Paul873a95e2020-04-03 15:47:15 -04004737 } else if (status < 0) {
Lyude Paul4d1b58d2020-04-03 15:58:29 -04004738 /*
4739 * Failure here isn't unexpected - the hub may have
4740 * just been unplugged
4741 */
Lyude Paul3a08f532021-04-23 14:43:09 -04004742 drm_dbg_kms(mgr->dev, "Failed to read payload table status: %d\n", status);
Lyude Paul873a95e2020-04-03 15:47:15 -04004743 return status;
Dave Airliead7f8a12014-06-05 14:01:32 +10004744 }
Lyude Paul873a95e2020-04-03 15:47:15 -04004745
Dave Airliead7f8a12014-06-05 14:01:32 +10004746 return 0;
Dave Airliead7f8a12014-06-05 14:01:32 +10004747}
4748EXPORT_SYMBOL(drm_dp_check_act_status);
4749
4750/**
4751 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
Ville Syrjälä7707dd62023-10-24 04:08:57 +03004752 * @clock: dot clock
4753 * @bpp: bpp as .4 binary fixed point
Dave Airliead7f8a12014-06-05 14:01:32 +10004754 *
4755 * This uses the formula in the spec to calculate the PBN value for a mode.
4756 */
Ville Syrjälä7707dd62023-10-24 04:08:57 +03004757int drm_dp_calc_pbn_mode(int clock, int bpp)
Dave Airliead7f8a12014-06-05 14:01:32 +10004758{
Harry Wentlanda9ebb3e2016-01-22 17:07:26 -05004759 /*
Harry Wentlanda9ebb3e2016-01-22 17:07:26 -05004760 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on
4761 * common multiplier to render an integer PBN for all link rate/lane
4762 * counts combinations
4763 * calculate
Imre Deakc1d6a22b2023-10-24 13:22:17 +03004764 * peak_kbps = clock * bpp / 16
4765 * peak_kbps *= SSC overhead / 1000000
4766 * peak_kbps /= 8 convert to Kbytes
4767 * peak_kBps *= (64/54) / 1000 convert to PBN
Harry Wentlanda9ebb3e2016-01-22 17:07:26 -05004768 */
Imre Deakc1d6a22b2023-10-24 13:22:17 +03004769 /*
4770 * TODO: Use the actual link and mode parameters to calculate
4771 * the overhead. For now it's assumed that these are
4772 * 4 link lanes, 4096 hactive pixels, which don't add any
4773 * significant data padding overhead and that there is no DSC
4774 * or FEC overhead.
4775 */
4776 int overhead = drm_dp_bw_overhead(4, 4096, 0, bpp,
4777 DRM_DP_BW_OVERHEAD_MST |
4778 DRM_DP_BW_OVERHEAD_SSC_REF_CLK);
David Francisdc485292019-08-21 10:33:26 -04004779
Imre Deakc1d6a22b2023-10-24 13:22:17 +03004780 return DIV64_U64_ROUND_UP(mul_u32_u32(clock * bpp, 64 * overhead >> 4),
4781 1000000ULL * 8 * 54 * 1000);
Dave Airliead7f8a12014-06-05 14:01:32 +10004782}
4783EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
4784
Dave Airliead7f8a12014-06-05 14:01:32 +10004785/* we want to kick the TX after we've ack the up/down IRQs. */
4786static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
4787{
4788 queue_work(system_long_wq, &mgr->tx_work);
4789}
4790
Eryk Brole55f2ff2021-03-25 14:06:14 -04004791/*
4792 * Helper function for parsing DP device types into convenient strings
4793 * for use with dp_mst_topology
4794 */
4795static const char *pdt_to_string(u8 pdt)
4796{
4797 switch (pdt) {
4798 case DP_PEER_DEVICE_NONE:
4799 return "NONE";
4800 case DP_PEER_DEVICE_SOURCE_OR_SST:
4801 return "SOURCE OR SST";
4802 case DP_PEER_DEVICE_MST_BRANCHING:
4803 return "MST BRANCHING";
4804 case DP_PEER_DEVICE_SST_SINK:
4805 return "SST SINK";
4806 case DP_PEER_DEVICE_DP_LEGACY_CONV:
4807 return "DP LEGACY CONV";
4808 default:
4809 return "ERR";
4810 }
4811}
4812
Dave Airliead7f8a12014-06-05 14:01:32 +10004813static void drm_dp_mst_dump_mstb(struct seq_file *m,
4814 struct drm_dp_mst_branch *mstb)
4815{
4816 struct drm_dp_mst_port *port;
4817 int tabs = mstb->lct;
4818 char prefix[10];
4819 int i;
4820
4821 for (i = 0; i < tabs; i++)
4822 prefix[i] = '\t';
4823 prefix[i] = '\0';
4824
Eryk Brole55f2ff2021-03-25 14:06:14 -04004825 seq_printf(m, "%smstb - [%p]: num_ports: %d\n", prefix, mstb, mstb->num_ports);
Dave Airliead7f8a12014-06-05 14:01:32 +10004826 list_for_each_entry(port, &mstb->ports, next) {
Thomas Zimmermanndfacce52022-01-14 12:45:31 +01004827 seq_printf(m, "%sport %d - [%p] (%s - %s): ddps: %d, ldps: %d, sdp: %d/%d, fec: %s, conn: %p\n",
Eryk Brole55f2ff2021-03-25 14:06:14 -04004828 prefix,
4829 port->port_num,
4830 port,
4831 port->input ? "input" : "output",
4832 pdt_to_string(port->pdt),
4833 port->ddps,
4834 port->ldps,
4835 port->num_sdp_streams,
4836 port->num_sdp_stream_sinks,
4837 port->fec_capable ? "true" : "false",
4838 port->connector);
Dave Airliead7f8a12014-06-05 14:01:32 +10004839 if (port->mstb)
4840 drm_dp_mst_dump_mstb(m, port->mstb);
4841 }
4842}
4843
Andy Shevchenko7056a2b2018-03-19 16:19:32 +02004844#define DP_PAYLOAD_TABLE_SIZE 64
4845
Dave Airliead7f8a12014-06-05 14:01:32 +10004846static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
4847 char *buf)
4848{
Dave Airliead7f8a12014-06-05 14:01:32 +10004849 int i;
Joe Perches46466b02017-05-30 16:35:37 -07004850
Andy Shevchenko7056a2b2018-03-19 16:19:32 +02004851 for (i = 0; i < DP_PAYLOAD_TABLE_SIZE; i += 16) {
Joe Perches46466b02017-05-30 16:35:37 -07004852 if (drm_dp_dpcd_read(mgr->aux,
4853 DP_PAYLOAD_TABLE_UPDATE_STATUS + i,
4854 &buf[i], 16) != 16)
4855 return false;
Dave Airliead7f8a12014-06-05 14:01:32 +10004856 }
Joe Perches46466b02017-05-30 16:35:37 -07004857 return true;
Dave Airliead7f8a12014-06-05 14:01:32 +10004858}
4859
Jim Bride51108f22016-04-14 10:18:36 -07004860static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr,
4861 struct drm_dp_mst_port *port, char *name,
4862 int namelen)
4863{
4864 struct edid *mst_edid;
4865
4866 mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port);
4867 drm_edid_get_monitor_name(mst_edid, name, namelen);
Hangyu Hua6e03b132022-05-16 11:20:42 +08004868 kfree(mst_edid);
Jim Bride51108f22016-04-14 10:18:36 -07004869}
4870
Dave Airliead7f8a12014-06-05 14:01:32 +10004871/**
4872 * drm_dp_mst_dump_topology(): dump topology to seq file.
4873 * @m: seq_file to dump output to
4874 * @mgr: manager to dump current topology for.
4875 *
4876 * helper to dump MST topology to a seq file for debugfs.
4877 */
4878void drm_dp_mst_dump_topology(struct seq_file *m,
4879 struct drm_dp_mst_topology_mgr *mgr)
4880{
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004881 struct drm_dp_mst_topology_state *state;
4882 struct drm_dp_mst_atomic_payload *payload;
4883 int i, ret;
Jim Bride51108f22016-04-14 10:18:36 -07004884
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004885 static const char *const status[] = {
4886 "None",
4887 "Local",
4888 "DFP",
4889 "Remote",
4890 };
4891
Dave Airliead7f8a12014-06-05 14:01:32 +10004892 mutex_lock(&mgr->lock);
4893 if (mgr->mst_primary)
4894 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
4895
4896 /* dump VCPIs */
4897 mutex_unlock(&mgr->lock);
4898
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004899 ret = drm_modeset_lock_single_interruptible(&mgr->base.lock);
4900 if (ret < 0)
4901 return;
Dave Airliead7f8a12014-06-05 14:01:32 +10004902
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004903 state = to_drm_dp_mst_topology_state(mgr->base.state);
4904 seq_printf(m, "\n*** Atomic state info ***\n");
4905 seq_printf(m, "payload_mask: %x, max_payloads: %d, start_slot: %u, pbn_div: %d\n",
Imre Deak191dc432023-11-16 15:18:31 +02004906 state->payload_mask, mgr->max_payloads, state->start_slot,
4907 dfixed_trunc(state->pbn_div));
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004908
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004909 seq_printf(m, "\n| idx | port | vcpi | slots | pbn | dsc | status | sink name |\n");
Dave Airliead7f8a12014-06-05 14:01:32 +10004910 for (i = 0; i < mgr->max_payloads; i++) {
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004911 list_for_each_entry(payload, &state->payloads, next) {
Jim Bride51108f22016-04-14 10:18:36 -07004912 char name[14];
4913
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004914 if (payload->vcpi != i || payload->delete)
4915 continue;
4916
4917 fetch_monitor_name(mgr, payload->port, name, sizeof(name));
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004918 seq_printf(m, " %5d %6d %6d %02d - %02d %5d %5s %8s %19s\n",
Eryk Brole55f2ff2021-03-25 14:06:14 -04004919 i,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004920 payload->port->port_num,
4921 payload->vcpi,
4922 payload->vc_start_slot,
4923 payload->vc_start_slot + payload->time_slots - 1,
4924 payload->pbn,
4925 payload->dsc_enabled ? "Y" : "N",
Wayne Lin5aa1dfc2023-08-07 10:56:38 +08004926 status[payload->payload_allocation_status],
Eryk Brole55f2ff2021-03-25 14:06:14 -04004927 (*name != 0) ? name : "Unknown");
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004928 }
Dave Airliead7f8a12014-06-05 14:01:32 +10004929 }
Dave Airliead7f8a12014-06-05 14:01:32 +10004930
Eryk Brole55f2ff2021-03-25 14:06:14 -04004931 seq_printf(m, "\n*** DPCD Info ***\n");
Dave Airliead7f8a12014-06-05 14:01:32 +10004932 mutex_lock(&mgr->lock);
4933 if (mgr->mst_primary) {
Andy Shevchenko7056a2b2018-03-19 16:19:32 +02004934 u8 buf[DP_PAYLOAD_TABLE_SIZE];
Dave Airliead7f8a12014-06-05 14:01:32 +10004935 int ret;
Joe Perches46466b02017-05-30 16:35:37 -07004936
Imre Deak7a710a82022-06-14 12:45:37 +03004937 if (drm_dp_read_dpcd_caps(mgr->aux, buf) < 0) {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004938 seq_printf(m, "dpcd read failed\n");
4939 goto out;
4940 }
Joe Perches46466b02017-05-30 16:35:37 -07004941 seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf);
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004942
Dave Airliead7f8a12014-06-05 14:01:32 +10004943 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
Simon Ser2ac6cdd2022-02-10 15:40:25 +00004944 if (ret != 2) {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004945 seq_printf(m, "faux/mst read failed\n");
4946 goto out;
4947 }
Joe Perches46466b02017-05-30 16:35:37 -07004948 seq_printf(m, "faux/mst: %*ph\n", 2, buf);
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004949
Dave Airliead7f8a12014-06-05 14:01:32 +10004950 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
Simon Ser2ac6cdd2022-02-10 15:40:25 +00004951 if (ret != 1) {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004952 seq_printf(m, "mst ctrl read failed\n");
4953 goto out;
4954 }
Joe Perches46466b02017-05-30 16:35:37 -07004955 seq_printf(m, "mst ctrl: %*ph\n", 1, buf);
Dave Airliead7f8a12014-06-05 14:01:32 +10004956
Dave Airlie44790462015-07-14 11:33:31 +10004957 /* dump the standard OUI branch header */
4958 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
Simon Ser2ac6cdd2022-02-10 15:40:25 +00004959 if (ret != DP_BRANCH_OUI_HEADER_SIZE) {
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004960 seq_printf(m, "branch oui read failed\n");
4961 goto out;
4962 }
Joe Perches46466b02017-05-30 16:35:37 -07004963 seq_printf(m, "branch oui: %*phN devid: ", 3, buf);
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004964
Jim Bride51108f22016-04-14 10:18:36 -07004965 for (i = 0x3; i < 0x8 && buf[i]; i++)
Dave Airlie44790462015-07-14 11:33:31 +10004966 seq_printf(m, "%c", buf[i]);
Joe Perches46466b02017-05-30 16:35:37 -07004967 seq_printf(m, " revision: hw: %x.%x sw: %x.%x\n",
4968 buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]);
4969 if (dump_dp_payload_table(mgr, buf))
Andy Shevchenko7056a2b2018-03-19 16:19:32 +02004970 seq_printf(m, "payload table: %*ph\n", DP_PAYLOAD_TABLE_SIZE, buf);
Dave Airliead7f8a12014-06-05 14:01:32 +10004971 }
4972
Benjamin Gaignardcb897542020-02-05 09:48:42 +01004973out:
Dave Airliead7f8a12014-06-05 14:01:32 +10004974 mutex_unlock(&mgr->lock);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04004975 drm_modeset_unlock(&mgr->base.lock);
Dave Airliead7f8a12014-06-05 14:01:32 +10004976}
4977EXPORT_SYMBOL(drm_dp_mst_dump_topology);
4978
4979static void drm_dp_tx_work(struct work_struct *work)
4980{
4981 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
4982
4983 mutex_lock(&mgr->qlock);
Lyude Pauld308a882020-04-24 14:13:08 -04004984 if (!list_empty(&mgr->tx_msg_downq))
Dave Airliead7f8a12014-06-05 14:01:32 +10004985 process_single_down_tx_qlock(mgr);
4986 mutex_unlock(&mgr->qlock);
4987}
4988
Lyude Paul7cb12d42019-02-19 17:41:02 -05004989static inline void
4990drm_dp_delayed_destroy_port(struct drm_dp_mst_port *port)
Dave Airlie6b8eeca2015-06-15 10:34:28 +10004991{
Imre Deak7d115072020-06-08 00:25:20 +03004992 drm_dp_port_set_pdt(port, DP_PEER_DEVICE_NONE, port->mcs);
4993
Lyude Paul72dc0f52020-03-31 16:57:37 -04004994 if (port->connector) {
4995 drm_connector_unregister(port->connector);
4996 drm_connector_put(port->connector);
4997 }
Lyude Paul7cb12d42019-02-19 17:41:02 -05004998
Lyude Paul7cb12d42019-02-19 17:41:02 -05004999 drm_dp_mst_put_port_malloc(port);
5000}
5001
5002static inline void
5003drm_dp_delayed_destroy_mstb(struct drm_dp_mst_branch *mstb)
5004{
5005 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
Lyude Pauld308a882020-04-24 14:13:08 -04005006 struct drm_dp_mst_port *port, *port_tmp;
5007 struct drm_dp_sideband_msg_tx *txmsg, *txmsg_tmp;
Lyude Paul7cb12d42019-02-19 17:41:02 -05005008 bool wake_tx = false;
5009
5010 mutex_lock(&mgr->lock);
Lyude Pauld308a882020-04-24 14:13:08 -04005011 list_for_each_entry_safe(port, port_tmp, &mstb->ports, next) {
Lyude Paul7cb12d42019-02-19 17:41:02 -05005012 list_del(&port->next);
5013 drm_dp_mst_topology_put_port(port);
5014 }
5015 mutex_unlock(&mgr->lock);
5016
Lyude Pauld308a882020-04-24 14:13:08 -04005017 /* drop any tx slot msg */
Lyude Paul7cb12d42019-02-19 17:41:02 -05005018 mutex_lock(&mstb->mgr->qlock);
Lyude Pauld308a882020-04-24 14:13:08 -04005019 list_for_each_entry_safe(txmsg, txmsg_tmp, &mgr->tx_msg_downq, next) {
5020 if (txmsg->dst != mstb)
5021 continue;
5022
5023 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
5024 list_del(&txmsg->next);
Lyude Paul7cb12d42019-02-19 17:41:02 -05005025 wake_tx = true;
5026 }
5027 mutex_unlock(&mstb->mgr->qlock);
5028
5029 if (wake_tx)
5030 wake_up_all(&mstb->mgr->tx_waitq);
5031
5032 drm_dp_mst_put_mstb_malloc(mstb);
5033}
5034
5035static void drm_dp_delayed_destroy_work(struct work_struct *work)
5036{
5037 struct drm_dp_mst_topology_mgr *mgr =
5038 container_of(work, struct drm_dp_mst_topology_mgr,
5039 delayed_destroy_work);
5040 bool send_hotplug = false, go_again;
5041
Dave Airlie6b8eeca2015-06-15 10:34:28 +10005042 /*
5043 * Not a regular list traverse as we have to drop the destroy
Lyude Paul7cb12d42019-02-19 17:41:02 -05005044 * connector lock before destroying the mstb/port, to avoid AB->BA
Dave Airlie6b8eeca2015-06-15 10:34:28 +10005045 * ordering between this lock and the config mutex.
5046 */
Lyude Paul7cb12d42019-02-19 17:41:02 -05005047 do {
5048 go_again = false;
5049
5050 for (;;) {
5051 struct drm_dp_mst_branch *mstb;
5052
5053 mutex_lock(&mgr->delayed_destroy_lock);
5054 mstb = list_first_entry_or_null(&mgr->destroy_branch_device_list,
5055 struct drm_dp_mst_branch,
5056 destroy_next);
5057 if (mstb)
5058 list_del(&mstb->destroy_next);
5059 mutex_unlock(&mgr->delayed_destroy_lock);
5060
5061 if (!mstb)
5062 break;
5063
5064 drm_dp_delayed_destroy_mstb(mstb);
5065 go_again = true;
Dave Airlie6b8eeca2015-06-15 10:34:28 +10005066 }
Dave Airlie6b8eeca2015-06-15 10:34:28 +10005067
Lyude Paul7cb12d42019-02-19 17:41:02 -05005068 for (;;) {
5069 struct drm_dp_mst_port *port;
Maarten Lankhorst4772ff02015-08-11 09:54:29 +02005070
Lyude Paul7cb12d42019-02-19 17:41:02 -05005071 mutex_lock(&mgr->delayed_destroy_lock);
5072 port = list_first_entry_or_null(&mgr->destroy_port_list,
5073 struct drm_dp_mst_port,
5074 next);
5075 if (port)
5076 list_del(&port->next);
5077 mutex_unlock(&mgr->delayed_destroy_lock);
Maarten Lankhorst4772ff02015-08-11 09:54:29 +02005078
Lyude Paul7cb12d42019-02-19 17:41:02 -05005079 if (!port)
5080 break;
5081
5082 drm_dp_delayed_destroy_port(port);
5083 send_hotplug = true;
5084 go_again = true;
5085 }
5086 } while (go_again);
5087
Dave Airliedf4839f2015-09-16 10:37:28 +10005088 if (send_hotplug)
Daniel Vetter16bff572018-11-28 23:12:34 +01005089 drm_kms_helper_hotplug_event(mgr->dev);
Dave Airlie6b8eeca2015-06-15 10:34:28 +10005090}
5091
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005092static struct drm_private_state *
5093drm_dp_mst_duplicate_state(struct drm_private_obj *obj)
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005094{
Lyude Pauleceae142019-01-10 19:53:41 -05005095 struct drm_dp_mst_topology_state *state, *old_state =
5096 to_dp_mst_topology_state(obj->state);
Lyude Paul48b6b372022-08-17 15:38:32 -04005097 struct drm_dp_mst_atomic_payload *pos, *payload;
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005098
Lyude Pauleceae142019-01-10 19:53:41 -05005099 state = kmemdup(old_state, sizeof(*state), GFP_KERNEL);
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005100 if (!state)
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005101 return NULL;
5102
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005103 __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
5104
Lyude Paul48b6b372022-08-17 15:38:32 -04005105 INIT_LIST_HEAD(&state->payloads);
Lyude Paula5c2c0d2022-08-17 15:38:37 -04005106 state->commit_deps = NULL;
5107 state->num_commit_deps = 0;
5108 state->pending_crtc_mask = 0;
Lyude Pauleceae142019-01-10 19:53:41 -05005109
Lyude Paul48b6b372022-08-17 15:38:32 -04005110 list_for_each_entry(pos, &old_state->payloads, next) {
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005111 /* Prune leftover freed timeslot allocations */
Lyude Paul6366fc72022-08-17 15:38:44 -04005112 if (pos->delete)
Lyude Pauleceae142019-01-10 19:53:41 -05005113 continue;
5114
Lyude Paul48b6b372022-08-17 15:38:32 -04005115 payload = kmemdup(pos, sizeof(*payload), GFP_KERNEL);
5116 if (!payload)
Lyude Pauleceae142019-01-10 19:53:41 -05005117 goto fail;
5118
Lyude Paul48b6b372022-08-17 15:38:32 -04005119 drm_dp_mst_get_port_malloc(payload->port);
5120 list_add(&payload->next, &state->payloads);
Lyude Pauleceae142019-01-10 19:53:41 -05005121 }
5122
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005123 return &state->base;
Lyude Pauleceae142019-01-10 19:53:41 -05005124
5125fail:
Lyude Paul48b6b372022-08-17 15:38:32 -04005126 list_for_each_entry_safe(pos, payload, &state->payloads, next) {
Lyude Pauleceae142019-01-10 19:53:41 -05005127 drm_dp_mst_put_port_malloc(pos->port);
5128 kfree(pos);
5129 }
5130 kfree(state);
5131
5132 return NULL;
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005133}
5134
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005135static void drm_dp_mst_destroy_state(struct drm_private_obj *obj,
5136 struct drm_private_state *state)
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005137{
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005138 struct drm_dp_mst_topology_state *mst_state =
5139 to_dp_mst_topology_state(state);
Lyude Paul48b6b372022-08-17 15:38:32 -04005140 struct drm_dp_mst_atomic_payload *pos, *tmp;
Lyude Paula5c2c0d2022-08-17 15:38:37 -04005141 int i;
Lyude Pauleceae142019-01-10 19:53:41 -05005142
Lyude Paul48b6b372022-08-17 15:38:32 -04005143 list_for_each_entry_safe(pos, tmp, &mst_state->payloads, next) {
Lyude Paul6366fc72022-08-17 15:38:44 -04005144 /* We only keep references to ports with active payloads */
5145 if (!pos->delete)
Lyude Pauleceae142019-01-10 19:53:41 -05005146 drm_dp_mst_put_port_malloc(pos->port);
5147 kfree(pos);
5148 }
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005149
Lyude Paula5c2c0d2022-08-17 15:38:37 -04005150 for (i = 0; i < mst_state->num_commit_deps; i++)
5151 drm_crtc_commit_put(mst_state->commit_deps[i]);
5152
5153 kfree(mst_state->commit_deps);
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005154 kfree(mst_state);
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005155}
5156
Mikita Lipskicd82d822019-11-06 13:11:23 -05005157static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port,
5158 struct drm_dp_mst_branch *branch)
5159{
5160 while (port->parent) {
5161 if (port->parent == branch)
5162 return true;
5163
5164 if (port->parent->port_parent)
5165 port = port->parent->port_parent;
5166 else
5167 break;
5168 }
5169 return false;
5170}
5171
Imre Deak9dcf67d2023-10-24 04:08:58 +03005172static bool
5173drm_dp_mst_port_downstream_of_parent_locked(struct drm_dp_mst_topology_mgr *mgr,
5174 struct drm_dp_mst_port *port,
5175 struct drm_dp_mst_port *parent)
5176{
5177 if (!mgr->mst_primary)
5178 return false;
5179
5180 port = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary,
5181 port);
5182 if (!port)
5183 return false;
5184
5185 if (!parent)
5186 return true;
5187
5188 parent = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary,
5189 parent);
5190 if (!parent)
5191 return false;
5192
5193 if (!parent->mstb)
5194 return false;
5195
5196 return drm_dp_mst_port_downstream_of_branch(port, parent->mstb);
5197}
5198
5199/**
5200 * drm_dp_mst_port_downstream_of_parent - check if a port is downstream of a parent port
5201 * @mgr: MST topology manager
5202 * @port: the port being looked up
5203 * @parent: the parent port
5204 *
5205 * The function returns %true if @port is downstream of @parent. If @parent is
5206 * %NULL - denoting the root port - the function returns %true if @port is in
5207 * @mgr's topology.
5208 */
5209bool
5210drm_dp_mst_port_downstream_of_parent(struct drm_dp_mst_topology_mgr *mgr,
5211 struct drm_dp_mst_port *port,
5212 struct drm_dp_mst_port *parent)
5213{
5214 bool ret;
5215
5216 mutex_lock(&mgr->lock);
5217 ret = drm_dp_mst_port_downstream_of_parent_locked(mgr, port, parent);
5218 mutex_unlock(&mgr->lock);
5219
5220 return ret;
5221}
5222EXPORT_SYMBOL(drm_dp_mst_port_downstream_of_parent);
5223
Lyude Paul047d4cd2020-03-09 17:01:31 -04005224static int
5225drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port,
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005226 struct drm_dp_mst_topology_state *state,
5227 struct drm_dp_mst_port **failing_port);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005228
5229static int
5230drm_dp_mst_atomic_check_mstb_bw_limit(struct drm_dp_mst_branch *mstb,
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005231 struct drm_dp_mst_topology_state *state,
5232 struct drm_dp_mst_port **failing_port)
Mikita Lipskicd82d822019-11-06 13:11:23 -05005233{
Lyude Paul48b6b372022-08-17 15:38:32 -04005234 struct drm_dp_mst_atomic_payload *payload;
Lyude Paul047d4cd2020-03-09 17:01:31 -04005235 struct drm_dp_mst_port *port;
5236 int pbn_used = 0, ret;
5237 bool found = false;
Mikita Lipskicd82d822019-11-06 13:11:23 -05005238
Lyude Paul047d4cd2020-03-09 17:01:31 -04005239 /* Check that we have at least one port in our state that's downstream
5240 * of this branch, otherwise we can skip this branch
5241 */
Lyude Paul48b6b372022-08-17 15:38:32 -04005242 list_for_each_entry(payload, &state->payloads, next) {
5243 if (!payload->pbn ||
5244 !drm_dp_mst_port_downstream_of_branch(payload->port, mstb))
Mikita Lipskicd82d822019-11-06 13:11:23 -05005245 continue;
5246
Lyude Paul047d4cd2020-03-09 17:01:31 -04005247 found = true;
5248 break;
Mikita Lipskicd82d822019-11-06 13:11:23 -05005249 }
Lyude Paul047d4cd2020-03-09 17:01:31 -04005250 if (!found)
5251 return 0;
Mikita Lipskicd82d822019-11-06 13:11:23 -05005252
Lyude Paul047d4cd2020-03-09 17:01:31 -04005253 if (mstb->port_parent)
Lyude Paul3a08f532021-04-23 14:43:09 -04005254 drm_dbg_atomic(mstb->mgr->dev,
5255 "[MSTB:%p] [MST PORT:%p] Checking bandwidth limits on [MSTB:%p]\n",
5256 mstb->port_parent->parent, mstb->port_parent, mstb);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005257 else
Lyude Paul3a08f532021-04-23 14:43:09 -04005258 drm_dbg_atomic(mstb->mgr->dev, "[MSTB:%p] Checking bandwidth limits\n", mstb);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005259
5260 list_for_each_entry(port, &mstb->ports, next) {
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005261 ret = drm_dp_mst_atomic_check_port_bw_limit(port, state, failing_port);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005262 if (ret < 0)
5263 return ret;
5264
5265 pbn_used += ret;
5266 }
5267
5268 return pbn_used;
5269}
5270
5271static int
5272drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port,
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005273 struct drm_dp_mst_topology_state *state,
5274 struct drm_dp_mst_port **failing_port)
Lyude Paul047d4cd2020-03-09 17:01:31 -04005275{
Lyude Paul48b6b372022-08-17 15:38:32 -04005276 struct drm_dp_mst_atomic_payload *payload;
Lyude Paul047d4cd2020-03-09 17:01:31 -04005277 int pbn_used = 0;
5278
5279 if (port->pdt == DP_PEER_DEVICE_NONE)
5280 return 0;
5281
5282 if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) {
Lyude Paul0b4e4772022-08-17 15:38:36 -04005283 payload = drm_atomic_get_mst_payload_state(state, port);
5284 if (!payload)
Lyude Paul047d4cd2020-03-09 17:01:31 -04005285 return 0;
5286
Imre Deakf0297cc2021-02-16 14:34:48 +02005287 /*
5288 * This could happen if the sink deasserted its HPD line, but
5289 * the branch device still reports it as attached (PDT != NONE).
Lyude Paul047d4cd2020-03-09 17:01:31 -04005290 */
Imre Deakf0297cc2021-02-16 14:34:48 +02005291 if (!port->full_pbn) {
5292 drm_dbg_atomic(port->mgr->dev,
5293 "[MSTB:%p] [MST PORT:%p] no BW available for the port\n",
5294 port->parent, port);
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005295 *failing_port = port;
Lyude Paul047d4cd2020-03-09 17:01:31 -04005296 return -EINVAL;
Imre Deakf0297cc2021-02-16 14:34:48 +02005297 }
Lyude Paul047d4cd2020-03-09 17:01:31 -04005298
Lyude Paul48b6b372022-08-17 15:38:32 -04005299 pbn_used = payload->pbn;
Lyude Paul047d4cd2020-03-09 17:01:31 -04005300 } else {
5301 pbn_used = drm_dp_mst_atomic_check_mstb_bw_limit(port->mstb,
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005302 state,
5303 failing_port);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005304 if (pbn_used <= 0)
5305 return pbn_used;
5306 }
5307
5308 if (pbn_used > port->full_pbn) {
Lyude Paul3a08f532021-04-23 14:43:09 -04005309 drm_dbg_atomic(port->mgr->dev,
5310 "[MSTB:%p] [MST PORT:%p] required PBN of %d exceeds port limit of %d\n",
5311 port->parent, port, pbn_used, port->full_pbn);
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005312 *failing_port = port;
Mikita Lipskicd82d822019-11-06 13:11:23 -05005313 return -ENOSPC;
5314 }
Lyude Paul047d4cd2020-03-09 17:01:31 -04005315
Lyude Paul3a08f532021-04-23 14:43:09 -04005316 drm_dbg_atomic(port->mgr->dev, "[MSTB:%p] [MST PORT:%p] uses %d out of %d PBN\n",
5317 port->parent, port, pbn_used, port->full_pbn);
Lyude Paul047d4cd2020-03-09 17:01:31 -04005318
5319 return pbn_used;
Mikita Lipskicd82d822019-11-06 13:11:23 -05005320}
5321
Lyude Pauleceae142019-01-10 19:53:41 -05005322static inline int
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005323drm_dp_mst_atomic_check_payload_alloc_limits(struct drm_dp_mst_topology_mgr *mgr,
5324 struct drm_dp_mst_topology_state *mst_state)
Lyude Pauleceae142019-01-10 19:53:41 -05005325{
Lyude Paul48b6b372022-08-17 15:38:32 -04005326 struct drm_dp_mst_atomic_payload *payload;
Bhawanpreet Lakhad6c6a762021-10-25 18:38:22 -04005327 int avail_slots = mst_state->total_avail_slots, payload_count = 0;
Lyude Pauleceae142019-01-10 19:53:41 -05005328
Lyude Paul48b6b372022-08-17 15:38:32 -04005329 list_for_each_entry(payload, &mst_state->payloads, next) {
5330 /* Releasing payloads is always OK-even if the port is gone */
Lyude Paul6366fc72022-08-17 15:38:44 -04005331 if (payload->delete) {
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005332 drm_dbg_atomic(mgr->dev, "[MST PORT:%p] releases all time slots\n",
Lyude Paul48b6b372022-08-17 15:38:32 -04005333 payload->port);
Lyude Pauleceae142019-01-10 19:53:41 -05005334 continue;
5335 }
5336
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005337 drm_dbg_atomic(mgr->dev, "[MST PORT:%p] requires %d time slots\n",
5338 payload->port, payload->time_slots);
Lyude Pauleceae142019-01-10 19:53:41 -05005339
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005340 avail_slots -= payload->time_slots;
Lyude Pauleceae142019-01-10 19:53:41 -05005341 if (avail_slots < 0) {
Lyude Paul3a08f532021-04-23 14:43:09 -04005342 drm_dbg_atomic(mgr->dev,
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005343 "[MST PORT:%p] not enough time slots in mst state %p (avail=%d)\n",
5344 payload->port, mst_state, avail_slots + payload->time_slots);
Lyude Pauleceae142019-01-10 19:53:41 -05005345 return -ENOSPC;
5346 }
Lyude Paul5e187a02019-01-10 19:53:42 -05005347
5348 if (++payload_count > mgr->max_payloads) {
Lyude Paul3a08f532021-04-23 14:43:09 -04005349 drm_dbg_atomic(mgr->dev,
5350 "[MST MGR:%p] state %p has too many payloads (max=%d)\n",
5351 mgr, mst_state, mgr->max_payloads);
Lyude Paul5e187a02019-01-10 19:53:42 -05005352 return -EINVAL;
5353 }
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005354
5355 /* Assign a VCPI */
5356 if (!payload->vcpi) {
5357 payload->vcpi = ffz(mst_state->payload_mask) + 1;
5358 drm_dbg_atomic(mgr->dev, "[MST PORT:%p] assigned VCPI #%d\n",
5359 payload->port, payload->vcpi);
5360 mst_state->payload_mask |= BIT(payload->vcpi - 1);
5361 }
Lyude Pauleceae142019-01-10 19:53:41 -05005362 }
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005363
5364 if (!payload_count)
Imre Deak191dc432023-11-16 15:18:31 +02005365 mst_state->pbn_div.full = dfixed_const(0);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005366
5367 drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p TU pbn_div=%d avail=%d used=%d\n",
Imre Deak191dc432023-11-16 15:18:31 +02005368 mgr, mst_state, dfixed_trunc(mst_state->pbn_div), avail_slots,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005369 mst_state->total_avail_slots - avail_slots);
Lyude Pauleceae142019-01-10 19:53:41 -05005370
5371 return 0;
5372}
5373
5374/**
Mikita Lipski8ec04672019-11-16 13:32:15 -05005375 * drm_dp_mst_add_affected_dsc_crtcs
5376 * @state: Pointer to the new struct drm_dp_mst_topology_state
Alex Deucher9edb4352020-01-08 22:21:30 -05005377 * @mgr: MST topology manager
Mikita Lipski8ec04672019-11-16 13:32:15 -05005378 *
5379 * Whenever there is a change in mst topology
5380 * DSC configuration would have to be recalculated
5381 * therefore we need to trigger modeset on all affected
5382 * CRTCs in that topology
5383 *
5384 * See also:
5385 * drm_dp_mst_atomic_enable_dsc()
5386 */
5387int drm_dp_mst_add_affected_dsc_crtcs(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr)
5388{
5389 struct drm_dp_mst_topology_state *mst_state;
Lyude Paul48b6b372022-08-17 15:38:32 -04005390 struct drm_dp_mst_atomic_payload *pos;
Mikita Lipski8ec04672019-11-16 13:32:15 -05005391 struct drm_connector *connector;
5392 struct drm_connector_state *conn_state;
5393 struct drm_crtc *crtc;
5394 struct drm_crtc_state *crtc_state;
5395
5396 mst_state = drm_atomic_get_mst_topology_state(state, mgr);
5397
5398 if (IS_ERR(mst_state))
Lyude Paula3ae9952022-11-14 17:17:53 -05005399 return PTR_ERR(mst_state);
Mikita Lipski8ec04672019-11-16 13:32:15 -05005400
Lyude Paul48b6b372022-08-17 15:38:32 -04005401 list_for_each_entry(pos, &mst_state->payloads, next) {
Mikita Lipski8ec04672019-11-16 13:32:15 -05005402
5403 connector = pos->port->connector;
5404
5405 if (!connector)
5406 return -EINVAL;
5407
5408 conn_state = drm_atomic_get_connector_state(state, connector);
5409
5410 if (IS_ERR(conn_state))
5411 return PTR_ERR(conn_state);
5412
5413 crtc = conn_state->crtc;
5414
Bhawanpreet Lakha88fee1c2020-08-14 13:01:40 -04005415 if (!crtc)
5416 continue;
Mikita Lipski8ec04672019-11-16 13:32:15 -05005417
5418 if (!drm_dp_mst_dsc_aux_for_port(pos->port))
5419 continue;
5420
5421 crtc_state = drm_atomic_get_crtc_state(mst_state->base.state, crtc);
5422
5423 if (IS_ERR(crtc_state))
5424 return PTR_ERR(crtc_state);
5425
Lyude Paul3a08f532021-04-23 14:43:09 -04005426 drm_dbg_atomic(mgr->dev, "[MST MGR:%p] Setting mode_changed flag on CRTC %p\n",
5427 mgr, crtc);
Mikita Lipski8ec04672019-11-16 13:32:15 -05005428
5429 crtc_state->mode_changed = true;
5430 }
5431 return 0;
5432}
5433EXPORT_SYMBOL(drm_dp_mst_add_affected_dsc_crtcs);
5434
5435/**
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005436 * drm_dp_mst_atomic_enable_dsc - Set DSC Enable Flag to On/Off
5437 * @state: Pointer to the new drm_atomic_state
5438 * @port: Pointer to the affected MST Port
5439 * @pbn: Newly recalculated bw required for link with DSC enabled
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005440 * @enable: Boolean flag to enable or disable DSC on the port
5441 *
5442 * This function enables DSC on the given Port
5443 * by recalculating its vcpi from pbn provided
5444 * and sets dsc_enable flag to keep track of which
5445 * ports have DSC enabled
5446 *
5447 */
5448int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state,
5449 struct drm_dp_mst_port *port,
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005450 int pbn, bool enable)
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005451{
5452 struct drm_dp_mst_topology_state *mst_state;
Lyude Paul0b4e4772022-08-17 15:38:36 -04005453 struct drm_dp_mst_atomic_payload *payload;
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005454 int time_slots = 0;
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005455
5456 mst_state = drm_atomic_get_mst_topology_state(state, port->mgr);
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005457 if (IS_ERR(mst_state))
5458 return PTR_ERR(mst_state);
5459
Lyude Paul0b4e4772022-08-17 15:38:36 -04005460 payload = drm_atomic_get_mst_payload_state(mst_state, port);
5461 if (!payload) {
Lyude Paul3a08f532021-04-23 14:43:09 -04005462 drm_dbg_atomic(state->dev,
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005463 "[MST PORT:%p] Couldn't find payload in mst state %p\n",
Lyude Paul3a08f532021-04-23 14:43:09 -04005464 port, mst_state);
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005465 return -EINVAL;
5466 }
5467
Lyude Paul0b4e4772022-08-17 15:38:36 -04005468 if (payload->dsc_enabled == enable) {
Lyude Paul3a08f532021-04-23 14:43:09 -04005469 drm_dbg_atomic(state->dev,
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005470 "[MST PORT:%p] DSC flag is already set to %d, returning %d time slots\n",
Lyude Paul0b4e4772022-08-17 15:38:36 -04005471 port, enable, payload->time_slots);
5472 time_slots = payload->time_slots;
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005473 }
5474
5475 if (enable) {
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005476 time_slots = drm_dp_atomic_find_time_slots(state, port->mgr, port, pbn);
Lyude Paul3a08f532021-04-23 14:43:09 -04005477 drm_dbg_atomic(state->dev,
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005478 "[MST PORT:%p] Enabling DSC flag, reallocating %d time slots on the port\n",
5479 port, time_slots);
5480 if (time_slots < 0)
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005481 return -EINVAL;
5482 }
5483
Lyude Paul0b4e4772022-08-17 15:38:36 -04005484 payload->dsc_enabled = enable;
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005485
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005486 return time_slots;
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005487}
5488EXPORT_SYMBOL(drm_dp_mst_atomic_enable_dsc);
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005489
Mikita Lipski8afb7e62019-10-28 17:33:32 -04005490/**
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005491 * drm_dp_mst_atomic_check_mgr - Check the atomic state of an MST topology manager
5492 * @state: The global atomic state
5493 * @mgr: Manager to check
5494 * @mst_state: The MST atomic state for @mgr
5495 * @failing_port: Returns the port with a BW limitation
5496 *
5497 * Checks the given MST manager's topology state for an atomic update to ensure
5498 * that it's valid. This includes checking whether there's enough bandwidth to
5499 * support the new timeslot allocations in the atomic update.
5500 *
5501 * Any atomic drivers supporting DP MST must make sure to call this or
5502 * the drm_dp_mst_atomic_check() function after checking the rest of their state
5503 * in their &drm_mode_config_funcs.atomic_check() callback.
5504 *
5505 * See also:
5506 * drm_dp_mst_atomic_check()
5507 * drm_dp_atomic_find_time_slots()
5508 * drm_dp_atomic_release_time_slots()
5509 *
5510 * Returns:
5511 * - 0 if the new state is valid
5512 * - %-ENOSPC, if the new state is invalid, because of BW limitation
5513 * @failing_port is set to:
Bagas Sanjaya1a84c212023-11-14 15:10:33 +07005514 *
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005515 * - The non-root port where a BW limit check failed
Imre Deakd075bca2023-10-24 04:09:00 +03005516 * with all the ports downstream of @failing_port passing
5517 * the BW limit check.
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005518 * The returned port pointer is valid until at least
5519 * one payload downstream of it exists.
5520 * - %NULL if the BW limit check failed at the root port
Imre Deakd075bca2023-10-24 04:09:00 +03005521 * with all the ports downstream of the root port passing
5522 * the BW limit check.
Bagas Sanjaya1a84c212023-11-14 15:10:33 +07005523 *
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005524 * - %-EINVAL, if the new state is invalid, because the root port has
5525 * too many payloads.
5526 */
5527int drm_dp_mst_atomic_check_mgr(struct drm_atomic_state *state,
5528 struct drm_dp_mst_topology_mgr *mgr,
5529 struct drm_dp_mst_topology_state *mst_state,
5530 struct drm_dp_mst_port **failing_port)
5531{
5532 int ret;
5533
5534 *failing_port = NULL;
5535
5536 if (!mgr->mst_state)
5537 return 0;
5538
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005539 mutex_lock(&mgr->lock);
5540 ret = drm_dp_mst_atomic_check_mstb_bw_limit(mgr->mst_primary,
5541 mst_state,
5542 failing_port);
5543 mutex_unlock(&mgr->lock);
5544
Imre Deakd075bca2023-10-24 04:09:00 +03005545 if (ret < 0)
5546 return ret;
5547
5548 return drm_dp_mst_atomic_check_payload_alloc_limits(mgr, mst_state);
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005549}
5550EXPORT_SYMBOL(drm_dp_mst_atomic_check_mgr);
5551
5552/**
Lyude Pauleceae142019-01-10 19:53:41 -05005553 * drm_dp_mst_atomic_check - Check that the new state of an MST topology in an
5554 * atomic update is valid
5555 * @state: Pointer to the new &struct drm_dp_mst_topology_state
5556 *
5557 * Checks the given topology state for an atomic update to ensure that it's
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005558 * valid, calling drm_dp_mst_atomic_check_mgr() for all MST manager in the
5559 * atomic state. This includes checking whether there's enough bandwidth to
5560 * support the new timeslot allocations in the atomic update.
Lyude Pauleceae142019-01-10 19:53:41 -05005561 *
5562 * Any atomic drivers supporting DP MST must make sure to call this after
5563 * checking the rest of their state in their
5564 * &drm_mode_config_funcs.atomic_check() callback.
5565 *
5566 * See also:
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005567 * drm_dp_mst_atomic_check_mgr()
Lyude Pauldf78f7f2022-08-17 15:38:33 -04005568 * drm_dp_atomic_find_time_slots()
5569 * drm_dp_atomic_release_time_slots()
Lyude Pauleceae142019-01-10 19:53:41 -05005570 *
5571 * Returns:
5572 *
5573 * 0 if the new state is valid, negative error code otherwise.
5574 */
5575int drm_dp_mst_atomic_check(struct drm_atomic_state *state)
5576{
5577 struct drm_dp_mst_topology_mgr *mgr;
5578 struct drm_dp_mst_topology_state *mst_state;
5579 int i, ret = 0;
5580
5581 for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) {
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005582 struct drm_dp_mst_port *tmp_port;
José Roberto de Souza7b199142020-01-16 17:58:34 -08005583
Imre Deak1cd0a5e2023-10-24 04:08:59 +03005584 ret = drm_dp_mst_atomic_check_mgr(state, mgr, mst_state, &tmp_port);
Lyude Pauleceae142019-01-10 19:53:41 -05005585 if (ret)
5586 break;
5587 }
5588
5589 return ret;
5590}
5591EXPORT_SYMBOL(drm_dp_mst_atomic_check);
5592
Lyude Paulbea5c382019-01-10 19:53:40 -05005593const struct drm_private_state_funcs drm_dp_mst_topology_state_funcs = {
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005594 .atomic_duplicate_state = drm_dp_mst_duplicate_state,
5595 .atomic_destroy_state = drm_dp_mst_destroy_state,
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005596};
Lyude Paulbea5c382019-01-10 19:53:40 -05005597EXPORT_SYMBOL(drm_dp_mst_topology_state_funcs);
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005598
5599/**
5600 * drm_atomic_get_mst_topology_state: get MST topology state
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005601 * @state: global atomic state
5602 * @mgr: MST topology manager, also the private object in this case
5603 *
5604 * This function wraps drm_atomic_get_priv_obj_state() passing in the MST atomic
5605 * state vtable so that the private object state returned is that of a MST
Lyude Paul87a34512022-06-02 16:17:57 -04005606 * topology object.
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005607 *
5608 * RETURNS:
5609 *
5610 * The MST topology state or error pointer.
5611 */
5612struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state,
5613 struct drm_dp_mst_topology_mgr *mgr)
5614{
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005615 return to_dp_mst_topology_state(drm_atomic_get_private_obj_state(state, &mgr->base));
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005616}
5617EXPORT_SYMBOL(drm_atomic_get_mst_topology_state);
5618
Dave Airliead7f8a12014-06-05 14:01:32 +10005619/**
Imre Deak9ffdb672023-02-06 13:48:55 +02005620 * drm_atomic_get_old_mst_topology_state: get old MST topology state in atomic state, if any
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005621 * @state: global atomic state
5622 * @mgr: MST topology manager, also the private object in this case
5623 *
Imre Deak9ffdb672023-02-06 13:48:55 +02005624 * This function wraps drm_atomic_get_old_private_obj_state() passing in the MST atomic
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005625 * state vtable so that the private object state returned is that of a MST
5626 * topology object.
5627 *
5628 * Returns:
5629 *
Imre Deak9ffdb672023-02-06 13:48:55 +02005630 * The old MST topology state, or NULL if there's no topology state for this MST mgr
5631 * in the global atomic state
5632 */
5633struct drm_dp_mst_topology_state *
5634drm_atomic_get_old_mst_topology_state(struct drm_atomic_state *state,
5635 struct drm_dp_mst_topology_mgr *mgr)
5636{
5637 struct drm_private_state *old_priv_state =
5638 drm_atomic_get_old_private_obj_state(state, &mgr->base);
5639
5640 return old_priv_state ? to_dp_mst_topology_state(old_priv_state) : NULL;
5641}
5642EXPORT_SYMBOL(drm_atomic_get_old_mst_topology_state);
5643
5644/**
5645 * drm_atomic_get_new_mst_topology_state: get new MST topology state in atomic state, if any
5646 * @state: global atomic state
5647 * @mgr: MST topology manager, also the private object in this case
5648 *
5649 * This function wraps drm_atomic_get_new_private_obj_state() passing in the MST atomic
5650 * state vtable so that the private object state returned is that of a MST
5651 * topology object.
5652 *
5653 * Returns:
5654 *
5655 * The new MST topology state, or NULL if there's no topology state for this MST mgr
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005656 * in the global atomic state
5657 */
5658struct drm_dp_mst_topology_state *
5659drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state,
5660 struct drm_dp_mst_topology_mgr *mgr)
5661{
Imre Deak9ffdb672023-02-06 13:48:55 +02005662 struct drm_private_state *new_priv_state =
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005663 drm_atomic_get_new_private_obj_state(state, &mgr->base);
5664
Imre Deak9ffdb672023-02-06 13:48:55 +02005665 return new_priv_state ? to_dp_mst_topology_state(new_priv_state) : NULL;
Lyude Paul4d07b0b2022-08-17 15:38:46 -04005666}
5667EXPORT_SYMBOL(drm_atomic_get_new_mst_topology_state);
5668
5669/**
Dave Airliead7f8a12014-06-05 14:01:32 +10005670 * drm_dp_mst_topology_mgr_init - initialise a topology manager
5671 * @mgr: manager struct to initialise
5672 * @dev: device providing this structure - for i2c addition.
5673 * @aux: DP helper aux channel to talk to this device
5674 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
5675 * @max_payloads: maximum number of payloads this GPU can source
5676 * @conn_base_id: the connector object ID the MST device is connected to.
5677 *
5678 * Return 0 for success, or negative error code on failure
5679 */
5680int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
Dhinakaran Pandiyan7b0a89a2017-01-24 15:49:29 -08005681 struct drm_device *dev, struct drm_dp_aux *aux,
Nikola Cornij98025a62021-04-29 18:11:51 -04005682 int max_dpcd_transaction_bytes, int max_payloads,
Nikola Cornij98025a62021-04-29 18:11:51 -04005683 int conn_base_id)
Dave Airliead7f8a12014-06-05 14:01:32 +10005684{
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005685 struct drm_dp_mst_topology_state *mst_state;
5686
Dave Airliead7f8a12014-06-05 14:01:32 +10005687 mutex_init(&mgr->lock);
5688 mutex_init(&mgr->qlock);
Lyude Paul7cb12d42019-02-19 17:41:02 -05005689 mutex_init(&mgr->delayed_destroy_lock);
Lyude Paul9408cc92019-06-17 16:37:18 -04005690 mutex_init(&mgr->up_req_lock);
Lyude Paul14692a32019-10-16 16:02:59 -04005691 mutex_init(&mgr->probe_lock);
Lyude Paul12a280c2019-06-20 17:59:25 -04005692#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
5693 mutex_init(&mgr->topology_ref_history_lock);
Vlastimil Babka2dba5eb2022-01-21 22:14:27 -08005694 stack_depot_init();
Lyude Paul12a280c2019-06-20 17:59:25 -04005695#endif
Dave Airliead7f8a12014-06-05 14:01:32 +10005696 INIT_LIST_HEAD(&mgr->tx_msg_downq);
Lyude Paul7cb12d42019-02-19 17:41:02 -05005697 INIT_LIST_HEAD(&mgr->destroy_port_list);
5698 INIT_LIST_HEAD(&mgr->destroy_branch_device_list);
Lyude Paul9408cc92019-06-17 16:37:18 -04005699 INIT_LIST_HEAD(&mgr->up_req_list);
Imre Deak72822c32020-06-10 16:47:04 +03005700
5701 /*
5702 * delayed_destroy_work will be queued on a dedicated WQ, so that any
5703 * requeuing will be also flushed when deiniting the topology manager.
5704 */
5705 mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0);
5706 if (mgr->delayed_destroy_wq == NULL)
5707 return -ENOMEM;
5708
Dave Airliead7f8a12014-06-05 14:01:32 +10005709 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
5710 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
Lyude Paul7cb12d42019-02-19 17:41:02 -05005711 INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work);
Lyude Paul9408cc92019-06-17 16:37:18 -04005712 INIT_WORK(&mgr->up_req_work, drm_dp_mst_up_req_work);
Dave Airliead7f8a12014-06-05 14:01:32 +10005713 init_waitqueue_head(&mgr->tx_waitq);
5714 mgr->dev = dev;
5715 mgr->aux = aux;
5716 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
5717 mgr->max_payloads = max_payloads;
5718 mgr->conn_base_id = conn_base_id;
Imre Deak441388a2016-01-29 14:44:28 +02005719
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005720 mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL);
5721 if (mst_state == NULL)
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005722 return -ENOMEM;
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005723
Bhawanpreet Lakhad6c6a762021-10-25 18:38:22 -04005724 mst_state->total_avail_slots = 63;
5725 mst_state->start_slot = 1;
5726
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005727 mst_state->mgr = mgr;
Lyude Paul48b6b372022-08-17 15:38:32 -04005728 INIT_LIST_HEAD(&mst_state->payloads);
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005729
Rob Clarkb962a122018-10-22 14:31:22 +02005730 drm_atomic_private_obj_init(dev, &mgr->base,
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005731 &mst_state->base,
Lyude Paulbea5c382019-01-10 19:53:40 -05005732 &drm_dp_mst_topology_state_funcs);
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005733
Dave Airliead7f8a12014-06-05 14:01:32 +10005734 return 0;
5735}
5736EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
5737
5738/**
5739 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
5740 * @mgr: manager to destroy
5741 */
5742void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
5743{
Lyude Paulf536e002018-12-11 18:50:26 -05005744 drm_dp_mst_topology_mgr_set_mst(mgr, false);
Dave Airlie274d8352015-09-30 10:39:42 +10005745 flush_work(&mgr->work);
Imre Deak72822c32020-06-10 16:47:04 +03005746 /* The following will also drain any requeued work on the WQ. */
5747 if (mgr->delayed_destroy_wq) {
5748 destroy_workqueue(mgr->delayed_destroy_wq);
5749 mgr->delayed_destroy_wq = NULL;
5750 }
Dave Airliead7f8a12014-06-05 14:01:32 +10005751 mgr->dev = NULL;
5752 mgr->aux = NULL;
Ville Syrjäläa4370c72017-07-12 18:51:02 +03005753 drm_atomic_private_obj_fini(&mgr->base);
Pandiyan, Dhinakaran3f3353b2017-04-20 22:51:31 -07005754 mgr->funcs = NULL;
Lyude Paul50094b52019-09-03 16:45:52 -04005755
Lyude Paul7cb12d42019-02-19 17:41:02 -05005756 mutex_destroy(&mgr->delayed_destroy_lock);
Lyude Paul50094b52019-09-03 16:45:52 -04005757 mutex_destroy(&mgr->qlock);
5758 mutex_destroy(&mgr->lock);
Lyude Paul9408cc92019-06-17 16:37:18 -04005759 mutex_destroy(&mgr->up_req_lock);
Lyude Paul14692a32019-10-16 16:02:59 -04005760 mutex_destroy(&mgr->probe_lock);
Lyude Paul12a280c2019-06-20 17:59:25 -04005761#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS)
5762 mutex_destroy(&mgr->topology_ref_history_lock);
5763#endif
Dave Airliead7f8a12014-06-05 14:01:32 +10005764}
5765EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
5766
Ville Syrjäläcb8ce712018-09-28 21:04:00 +03005767static bool remote_i2c_read_ok(const struct i2c_msg msgs[], int num)
5768{
5769 int i;
5770
5771 if (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)
5772 return false;
5773
5774 for (i = 0; i < num - 1; i++) {
5775 if (msgs[i].flags & I2C_M_RD ||
5776 msgs[i].len > 0xff)
5777 return false;
5778 }
5779
5780 return msgs[num - 1].flags & I2C_M_RD &&
5781 msgs[num - 1].len <= 0xff;
5782}
5783
Sam McNallyadb48b22020-07-27 16:03:37 +10005784static bool remote_i2c_write_ok(const struct i2c_msg msgs[], int num)
Dave Airliead7f8a12014-06-05 14:01:32 +10005785{
Sam McNallyadb48b22020-07-27 16:03:37 +10005786 int i;
5787
5788 for (i = 0; i < num - 1; i++) {
5789 if (msgs[i].flags & I2C_M_RD || !(msgs[i].flags & I2C_M_STOP) ||
5790 msgs[i].len > 0xff)
5791 return false;
5792 }
5793
5794 return !(msgs[num - 1].flags & I2C_M_RD) && msgs[num - 1].len <= 0xff;
5795}
5796
5797static int drm_dp_mst_i2c_read(struct drm_dp_mst_branch *mstb,
5798 struct drm_dp_mst_port *port,
5799 struct i2c_msg *msgs, int num)
5800{
Dave Airliead7f8a12014-06-05 14:01:32 +10005801 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
5802 unsigned int i;
Dave Airliead7f8a12014-06-05 14:01:32 +10005803 struct drm_dp_sideband_msg_req_body msg;
5804 struct drm_dp_sideband_msg_tx *txmsg = NULL;
5805 int ret;
5806
Dave Airlieae491542015-10-14 18:51:17 +10005807 memset(&msg, 0, sizeof(msg));
Dave Airliead7f8a12014-06-05 14:01:32 +10005808 msg.req_type = DP_REMOTE_I2C_READ;
5809 msg.u.i2c_read.num_transactions = num - 1;
5810 msg.u.i2c_read.port_number = port->port_num;
5811 for (i = 0; i < num - 1; i++) {
5812 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
5813 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
5814 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
Ville Syrjäläc978ae92018-09-28 21:03:59 +03005815 msg.u.i2c_read.transactions[i].no_stop_bit = !(msgs[i].flags & I2C_M_STOP);
Dave Airliead7f8a12014-06-05 14:01:32 +10005816 }
5817 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
5818 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
5819
5820 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
5821 if (!txmsg) {
5822 ret = -ENOMEM;
5823 goto out;
5824 }
5825
5826 txmsg->dst = mstb;
5827 drm_dp_encode_sideband_req(&msg, txmsg);
5828
5829 drm_dp_queue_down_tx(mgr, txmsg);
5830
5831 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
5832 if (ret > 0) {
5833
Ville Syrjälä45bbda12019-01-22 22:03:00 +02005834 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
Dave Airliead7f8a12014-06-05 14:01:32 +10005835 ret = -EREMOTEIO;
5836 goto out;
5837 }
5838 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
5839 ret = -EIO;
5840 goto out;
5841 }
5842 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
5843 ret = num;
5844 }
5845out:
5846 kfree(txmsg);
Sam McNallyadb48b22020-07-27 16:03:37 +10005847 return ret;
5848}
5849
5850static int drm_dp_mst_i2c_write(struct drm_dp_mst_branch *mstb,
5851 struct drm_dp_mst_port *port,
5852 struct i2c_msg *msgs, int num)
5853{
5854 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
5855 unsigned int i;
5856 struct drm_dp_sideband_msg_req_body msg;
5857 struct drm_dp_sideband_msg_tx *txmsg = NULL;
5858 int ret;
5859
5860 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
5861 if (!txmsg) {
5862 ret = -ENOMEM;
5863 goto out;
5864 }
5865 for (i = 0; i < num; i++) {
5866 memset(&msg, 0, sizeof(msg));
5867 msg.req_type = DP_REMOTE_I2C_WRITE;
5868 msg.u.i2c_write.port_number = port->port_num;
5869 msg.u.i2c_write.write_i2c_device_id = msgs[i].addr;
5870 msg.u.i2c_write.num_bytes = msgs[i].len;
5871 msg.u.i2c_write.bytes = msgs[i].buf;
5872
5873 memset(txmsg, 0, sizeof(*txmsg));
5874 txmsg->dst = mstb;
5875
5876 drm_dp_encode_sideband_req(&msg, txmsg);
5877 drm_dp_queue_down_tx(mgr, txmsg);
5878
5879 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
5880 if (ret > 0) {
5881 if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) {
5882 ret = -EREMOTEIO;
5883 goto out;
5884 }
5885 } else {
5886 goto out;
5887 }
5888 }
5889 ret = num;
5890out:
5891 kfree(txmsg);
5892 return ret;
5893}
5894
5895/* I2C device */
5896static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter,
5897 struct i2c_msg *msgs, int num)
5898{
5899 struct drm_dp_aux *aux = adapter->algo_data;
5900 struct drm_dp_mst_port *port =
5901 container_of(aux, struct drm_dp_mst_port, aux);
5902 struct drm_dp_mst_branch *mstb;
5903 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
5904 int ret;
5905
5906 mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent);
5907 if (!mstb)
5908 return -EREMOTEIO;
5909
5910 if (remote_i2c_read_ok(msgs, num)) {
5911 ret = drm_dp_mst_i2c_read(mstb, port, msgs, num);
5912 } else if (remote_i2c_write_ok(msgs, num)) {
5913 ret = drm_dp_mst_i2c_write(mstb, port, msgs, num);
5914 } else {
Lyude Paul3a08f532021-04-23 14:43:09 -04005915 drm_dbg_kms(mgr->dev, "Unsupported I2C transaction for MST device\n");
Sam McNallyadb48b22020-07-27 16:03:37 +10005916 ret = -EIO;
5917 }
5918
Lyude Pauld0757af2019-01-10 19:53:28 -05005919 drm_dp_mst_topology_put_mstb(mstb);
Dave Airliead7f8a12014-06-05 14:01:32 +10005920 return ret;
5921}
5922
5923static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
5924{
5925 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
5926 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
5927 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
5928 I2C_FUNC_10BIT_ADDR;
5929}
5930
5931static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
5932 .functionality = drm_dp_mst_i2c_functionality,
5933 .master_xfer = drm_dp_mst_i2c_xfer,
5934};
5935
5936/**
5937 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
Imre Deakd8bd15b2020-06-08 00:25:21 +03005938 * @port: The port to add the I2C bus on
Dave Airliead7f8a12014-06-05 14:01:32 +10005939 *
5940 * Returns 0 on success or a negative error code on failure.
5941 */
Imre Deakd8bd15b2020-06-08 00:25:21 +03005942static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10005943{
Imre Deakd8bd15b2020-06-08 00:25:21 +03005944 struct drm_dp_aux *aux = &port->aux;
5945 struct device *parent_dev = port->mgr->dev->dev;
5946
Dave Airliead7f8a12014-06-05 14:01:32 +10005947 aux->ddc.algo = &drm_dp_mst_i2c_algo;
5948 aux->ddc.algo_data = aux;
5949 aux->ddc.retries = 3;
5950
Dave Airliead7f8a12014-06-05 14:01:32 +10005951 aux->ddc.owner = THIS_MODULE;
Imre Deakd8bd15b2020-06-08 00:25:21 +03005952 /* FIXME: set the kdev of the port's connector as parent */
5953 aux->ddc.dev.parent = parent_dev;
5954 aux->ddc.dev.of_node = parent_dev->of_node;
Dave Airliead7f8a12014-06-05 14:01:32 +10005955
Azeem Shaikh533950d2023-05-22 15:51:24 +00005956 strscpy(aux->ddc.name, aux->name ? aux->name : dev_name(parent_dev),
Dave Airliead7f8a12014-06-05 14:01:32 +10005957 sizeof(aux->ddc.name));
5958
5959 return i2c_add_adapter(&aux->ddc);
5960}
5961
5962/**
5963 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
Imre Deakd8bd15b2020-06-08 00:25:21 +03005964 * @port: The port to remove the I2C bus from
Dave Airliead7f8a12014-06-05 14:01:32 +10005965 */
Imre Deakd8bd15b2020-06-08 00:25:21 +03005966static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port)
Dave Airliead7f8a12014-06-05 14:01:32 +10005967{
Imre Deakd8bd15b2020-06-08 00:25:21 +03005968 i2c_del_adapter(&port->aux.ddc);
Dave Airliead7f8a12014-06-05 14:01:32 +10005969}
David Francisc2bc1b62019-08-26 09:50:28 -04005970
5971/**
5972 * drm_dp_mst_is_virtual_dpcd() - Is the given port a virtual DP Peer Device
5973 * @port: The port to check
5974 *
5975 * A single physical MST hub object can be represented in the topology
5976 * by multiple branches, with virtual ports between those branches.
5977 *
5978 * As of DP1.4, An MST hub with internal (virtual) ports must expose
5979 * certain DPCD registers over those ports. See sections 2.6.1.1.1
5980 * and 2.6.1.1.2 of Display Port specification v1.4 for details.
5981 *
5982 * May acquire mgr->lock
5983 *
5984 * Returns:
5985 * true if the port is a virtual DP peer device, false otherwise
5986 */
5987static bool drm_dp_mst_is_virtual_dpcd(struct drm_dp_mst_port *port)
5988{
5989 struct drm_dp_mst_port *downstream_port;
5990
5991 if (!port || port->dpcd_rev < DP_DPCD_REV_14)
5992 return false;
5993
5994 /* Virtual DP Sink (Internal Display Panel) */
Imre Deakca5d9d72024-04-17 01:10:07 +03005995 if (drm_dp_mst_port_is_logical(port))
David Francisc2bc1b62019-08-26 09:50:28 -04005996 return true;
5997
5998 /* DP-to-HDMI Protocol Converter */
5999 if (port->pdt == DP_PEER_DEVICE_DP_LEGACY_CONV &&
6000 !port->mcs &&
6001 port->ldps)
6002 return true;
6003
6004 /* DP-to-DP */
6005 mutex_lock(&port->mgr->lock);
6006 if (port->pdt == DP_PEER_DEVICE_MST_BRANCHING &&
6007 port->mstb &&
6008 port->mstb->num_ports == 2) {
6009 list_for_each_entry(downstream_port, &port->mstb->ports, next) {
6010 if (downstream_port->pdt == DP_PEER_DEVICE_SST_SINK &&
6011 !downstream_port->input) {
6012 mutex_unlock(&port->mgr->lock);
6013 return true;
6014 }
6015 }
6016 }
6017 mutex_unlock(&port->mgr->lock);
6018
6019 return false;
6020}
6021
6022/**
Imre Deak93cb4092024-04-17 01:10:08 +03006023 * drm_dp_mst_aux_for_parent() - Get the AUX device for an MST port's parent
6024 * @port: MST port whose parent's AUX device is returned
6025 *
6026 * Return the AUX device for @port's parent or NULL if port's parent is the
6027 * root port.
6028 */
6029struct drm_dp_aux *drm_dp_mst_aux_for_parent(struct drm_dp_mst_port *port)
6030{
6031 if (!port->parent || !port->parent->port_parent)
6032 return NULL;
6033
6034 return &port->parent->port_parent->aux;
6035}
6036EXPORT_SYMBOL(drm_dp_mst_aux_for_parent);
6037
6038/**
David Francisc2bc1b62019-08-26 09:50:28 -04006039 * drm_dp_mst_dsc_aux_for_port() - Find the correct aux for DSC
6040 * @port: The port to check. A leaf of the MST tree with an attached display.
6041 *
6042 * Depending on the situation, DSC may be enabled via the endpoint aux,
6043 * the immediately upstream aux, or the connector's physical aux.
6044 *
6045 * This is both the correct aux to read DSC_CAPABILITY and the
6046 * correct aux to write DSC_ENABLED.
6047 *
6048 * This operation can be expensive (up to four aux reads), so
6049 * the caller should cache the return.
6050 *
6051 * Returns:
6052 * NULL if DSC cannot be enabled on this port, otherwise the aux device
6053 */
6054struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port)
6055{
6056 struct drm_dp_mst_port *immediate_upstream_port;
Imre Deak6f1aa392023-10-24 04:09:01 +03006057 struct drm_dp_aux *immediate_upstream_aux;
David Francisc2bc1b62019-08-26 09:50:28 -04006058 struct drm_dp_mst_port *fec_port;
Chris Wilsona4292e52020-05-16 22:23:30 +01006059 struct drm_dp_desc desc = {};
David Francisc2bc1b62019-08-26 09:50:28 -04006060 u8 endpoint_fec;
6061 u8 endpoint_dsc;
6062
6063 if (!port)
6064 return NULL;
6065
6066 if (port->parent->port_parent)
6067 immediate_upstream_port = port->parent->port_parent;
6068 else
6069 immediate_upstream_port = NULL;
6070
6071 fec_port = immediate_upstream_port;
6072 while (fec_port) {
6073 /*
6074 * Each physical link (i.e. not a virtual port) between the
6075 * output and the primary device must support FEC
6076 */
6077 if (!drm_dp_mst_is_virtual_dpcd(fec_port) &&
6078 !fec_port->fec_capable)
6079 return NULL;
6080
6081 fec_port = fec_port->parent->port_parent;
6082 }
6083
6084 /* DP-to-DP peer device */
6085 if (drm_dp_mst_is_virtual_dpcd(immediate_upstream_port)) {
6086 u8 upstream_dsc;
6087
6088 if (drm_dp_dpcd_read(&port->aux,
6089 DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1)
6090 return NULL;
6091 if (drm_dp_dpcd_read(&port->aux,
6092 DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1)
6093 return NULL;
6094 if (drm_dp_dpcd_read(&immediate_upstream_port->aux,
6095 DP_DSC_SUPPORT, &upstream_dsc, 1) != 1)
6096 return NULL;
6097
6098 /* Enpoint decompression with DP-to-DP peer device */
6099 if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) &&
6100 (endpoint_fec & DP_FEC_CAPABLE) &&
Hamza Mahfooz34f66762022-08-04 14:06:55 -04006101 (upstream_dsc & DP_DSC_PASSTHROUGH_IS_SUPPORTED)) {
6102 port->passthrough_aux = &immediate_upstream_port->aux;
David Francisc2bc1b62019-08-26 09:50:28 -04006103 return &port->aux;
Hamza Mahfooz34f66762022-08-04 14:06:55 -04006104 }
David Francisc2bc1b62019-08-26 09:50:28 -04006105
6106 /* Virtual DPCD decompression with DP-to-DP peer device */
6107 return &immediate_upstream_port->aux;
6108 }
6109
6110 /* Virtual DPCD decompression with DP-to-HDMI or Virtual DP Sink */
6111 if (drm_dp_mst_is_virtual_dpcd(port))
6112 return &port->aux;
6113
6114 /*
Mikita Lipski5b03f9d2019-09-20 15:44:56 -04006115 * Synaptics quirk
6116 * Applies to ports for which:
6117 * - Physical aux has Synaptics OUI
6118 * - DPv1.4 or higher
6119 * - Port is on primary branch device
6120 * - Not a VGA adapter (DP_DWN_STRM_PORT_TYPE_ANALOG)
6121 */
Imre Deak6f1aa392023-10-24 04:09:01 +03006122 if (immediate_upstream_port)
6123 immediate_upstream_aux = &immediate_upstream_port->aux;
6124 else
6125 immediate_upstream_aux = port->mgr->aux;
6126
6127 if (drm_dp_read_desc(immediate_upstream_aux, &desc, true))
Mikita Lipski5b03f9d2019-09-20 15:44:56 -04006128 return NULL;
6129
Imre Deak6f1aa392023-10-24 04:09:01 +03006130 if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD)) {
Nikola Cornij98025a62021-04-29 18:11:51 -04006131 u8 dpcd_ext[DP_RECEIVER_CAP_SIZE];
Mikita Lipski5b03f9d2019-09-20 15:44:56 -04006132
Imre Deak6f1aa392023-10-24 04:09:01 +03006133 if (drm_dp_read_dpcd_caps(immediate_upstream_aux, dpcd_ext) < 0)
Mikita Lipski5b03f9d2019-09-20 15:44:56 -04006134 return NULL;
6135
Imre Deak6f1aa392023-10-24 04:09:01 +03006136 if (dpcd_ext[DP_DPCD_REV] >= DP_DPCD_REV_14 &&
6137 ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT) &&
Nikola Cornij98025a62021-04-29 18:11:51 -04006138 ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK)
Imre Deak6f1aa392023-10-24 04:09:01 +03006139 != DP_DWN_STRM_PORT_TYPE_ANALOG)))
6140 return immediate_upstream_aux;
Mikita Lipski5b03f9d2019-09-20 15:44:56 -04006141 }
6142
6143 /*
David Francisc2bc1b62019-08-26 09:50:28 -04006144 * The check below verifies if the MST sink
6145 * connected to the GPU is capable of DSC -
6146 * therefore the endpoint needs to be
6147 * both DSC and FEC capable.
6148 */
6149 if (drm_dp_dpcd_read(&port->aux,
6150 DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1)
6151 return NULL;
6152 if (drm_dp_dpcd_read(&port->aux,
6153 DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1)
6154 return NULL;
6155 if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) &&
6156 (endpoint_fec & DP_FEC_CAPABLE))
6157 return &port->aux;
6158
6159 return NULL;
6160}
6161EXPORT_SYMBOL(drm_dp_mst_dsc_aux_for_port);