James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // Copyright (C) 2017 Arm Ltd. |
| 3 | #define pr_fmt(fmt) "sdei: " fmt |
| 4 | |
James Morse | f96935d | 2019-01-29 18:49:01 +0000 | [diff] [blame] | 5 | #include <acpi/ghes.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 6 | #include <linux/acpi.h> |
| 7 | #include <linux/arm_sdei.h> |
| 8 | #include <linux/arm-smccc.h> |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 9 | #include <linux/atomic.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 10 | #include <linux/bitops.h> |
| 11 | #include <linux/compiler.h> |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 12 | #include <linux/cpuhotplug.h> |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 13 | #include <linux/cpu.h> |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 14 | #include <linux/cpu_pm.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 15 | #include <linux/errno.h> |
| 16 | #include <linux/hardirq.h> |
| 17 | #include <linux/kernel.h> |
| 18 | #include <linux/kprobes.h> |
| 19 | #include <linux/kvm_host.h> |
| 20 | #include <linux/list.h> |
| 21 | #include <linux/mutex.h> |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 22 | #include <linux/notifier.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 23 | #include <linux/of.h> |
| 24 | #include <linux/of_platform.h> |
| 25 | #include <linux/percpu.h> |
| 26 | #include <linux/platform_device.h> |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 27 | #include <linux/pm.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 28 | #include <linux/ptrace.h> |
| 29 | #include <linux/preempt.h> |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 30 | #include <linux/reboot.h> |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 31 | #include <linux/slab.h> |
| 32 | #include <linux/smp.h> |
| 33 | #include <linux/spinlock.h> |
| 34 | #include <linux/uaccess.h> |
| 35 | |
| 36 | /* |
| 37 | * The call to use to reach the firmware. |
| 38 | */ |
| 39 | static asmlinkage void (*sdei_firmware_call)(unsigned long function_id, |
| 40 | unsigned long arg0, unsigned long arg1, |
| 41 | unsigned long arg2, unsigned long arg3, |
| 42 | unsigned long arg4, struct arm_smccc_res *res); |
| 43 | |
| 44 | /* entry point from firmware to arch asm code */ |
| 45 | static unsigned long sdei_entry_point; |
| 46 | |
| 47 | struct sdei_event { |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 48 | /* These three are protected by the sdei_list_lock */ |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 49 | struct list_head list; |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 50 | bool reregister; |
| 51 | bool reenable; |
| 52 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 53 | u32 event_num; |
| 54 | u8 type; |
| 55 | u8 priority; |
| 56 | |
| 57 | /* This pointer is handed to firmware as the event argument. */ |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 58 | union { |
| 59 | /* Shared events */ |
| 60 | struct sdei_registered_event *registered; |
| 61 | |
| 62 | /* CPU private events */ |
| 63 | struct sdei_registered_event __percpu *private_registered; |
| 64 | }; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 65 | }; |
| 66 | |
| 67 | /* Take the mutex for any API call or modification. Take the mutex first. */ |
| 68 | static DEFINE_MUTEX(sdei_events_lock); |
| 69 | |
| 70 | /* and then hold this when modifying the list */ |
| 71 | static DEFINE_SPINLOCK(sdei_list_lock); |
| 72 | static LIST_HEAD(sdei_list); |
| 73 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 74 | /* Private events are registered/enabled via IPI passing one of these */ |
| 75 | struct sdei_crosscall_args { |
| 76 | struct sdei_event *event; |
| 77 | atomic_t errors; |
| 78 | int first_error; |
| 79 | }; |
| 80 | |
| 81 | #define CROSSCALL_INIT(arg, event) (arg.event = event, \ |
| 82 | arg.first_error = 0, \ |
| 83 | atomic_set(&arg.errors, 0)) |
| 84 | |
| 85 | static inline int sdei_do_cross_call(void *fn, struct sdei_event * event) |
| 86 | { |
| 87 | struct sdei_crosscall_args arg; |
| 88 | |
| 89 | CROSSCALL_INIT(arg, event); |
| 90 | on_each_cpu(fn, &arg, true); |
| 91 | |
| 92 | return arg.first_error; |
| 93 | } |
| 94 | |
| 95 | static inline void |
| 96 | sdei_cross_call_return(struct sdei_crosscall_args *arg, int err) |
| 97 | { |
| 98 | if (err && (atomic_inc_return(&arg->errors) == 1)) |
| 99 | arg->first_error = err; |
| 100 | } |
| 101 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 102 | static int sdei_to_linux_errno(unsigned long sdei_err) |
| 103 | { |
| 104 | switch (sdei_err) { |
| 105 | case SDEI_NOT_SUPPORTED: |
| 106 | return -EOPNOTSUPP; |
| 107 | case SDEI_INVALID_PARAMETERS: |
| 108 | return -EINVAL; |
| 109 | case SDEI_DENIED: |
| 110 | return -EPERM; |
| 111 | case SDEI_PENDING: |
| 112 | return -EINPROGRESS; |
| 113 | case SDEI_OUT_OF_RESOURCE: |
| 114 | return -ENOMEM; |
| 115 | } |
| 116 | |
| 117 | /* Not an error value ... */ |
| 118 | return sdei_err; |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * If x0 is any of these values, then the call failed, use sdei_to_linux_errno() |
| 123 | * to translate. |
| 124 | */ |
| 125 | static int sdei_is_err(struct arm_smccc_res *res) |
| 126 | { |
| 127 | switch (res->a0) { |
| 128 | case SDEI_NOT_SUPPORTED: |
| 129 | case SDEI_INVALID_PARAMETERS: |
| 130 | case SDEI_DENIED: |
| 131 | case SDEI_PENDING: |
| 132 | case SDEI_OUT_OF_RESOURCE: |
| 133 | return true; |
| 134 | } |
| 135 | |
| 136 | return false; |
| 137 | } |
| 138 | |
| 139 | static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0, |
| 140 | unsigned long arg1, unsigned long arg2, |
| 141 | unsigned long arg3, unsigned long arg4, |
| 142 | u64 *result) |
| 143 | { |
| 144 | int err = 0; |
| 145 | struct arm_smccc_res res; |
| 146 | |
| 147 | if (sdei_firmware_call) { |
| 148 | sdei_firmware_call(function_id, arg0, arg1, arg2, arg3, arg4, |
| 149 | &res); |
| 150 | if (sdei_is_err(&res)) |
| 151 | err = sdei_to_linux_errno(res.a0); |
| 152 | } else { |
| 153 | /* |
| 154 | * !sdei_firmware_call means we failed to probe or called |
| 155 | * sdei_mark_interface_broken(). -EIO is not an error returned |
| 156 | * by sdei_to_linux_errno() and is used to suppress messages |
| 157 | * from this driver. |
| 158 | */ |
| 159 | err = -EIO; |
| 160 | res.a0 = SDEI_NOT_SUPPORTED; |
| 161 | } |
| 162 | |
| 163 | if (result) |
| 164 | *result = res.a0; |
| 165 | |
| 166 | return err; |
| 167 | } |
Xiongfeng Wang | 2f1d4e2 | 2019-04-26 10:16:36 +0800 | [diff] [blame] | 168 | NOKPROBE_SYMBOL(invoke_sdei_fn); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 169 | |
| 170 | static struct sdei_event *sdei_event_find(u32 event_num) |
| 171 | { |
| 172 | struct sdei_event *e, *found = NULL; |
| 173 | |
| 174 | lockdep_assert_held(&sdei_events_lock); |
| 175 | |
| 176 | spin_lock(&sdei_list_lock); |
| 177 | list_for_each_entry(e, &sdei_list, list) { |
| 178 | if (e->event_num == event_num) { |
| 179 | found = e; |
| 180 | break; |
| 181 | } |
| 182 | } |
| 183 | spin_unlock(&sdei_list_lock); |
| 184 | |
| 185 | return found; |
| 186 | } |
| 187 | |
| 188 | int sdei_api_event_context(u32 query, u64 *result) |
| 189 | { |
| 190 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_CONTEXT, query, 0, 0, 0, 0, |
| 191 | result); |
| 192 | } |
| 193 | NOKPROBE_SYMBOL(sdei_api_event_context); |
| 194 | |
| 195 | static int sdei_api_event_get_info(u32 event, u32 info, u64 *result) |
| 196 | { |
| 197 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0, |
| 198 | 0, 0, result); |
| 199 | } |
| 200 | |
| 201 | static struct sdei_event *sdei_event_create(u32 event_num, |
| 202 | sdei_event_callback *cb, |
| 203 | void *cb_arg) |
| 204 | { |
| 205 | int err; |
| 206 | u64 result; |
| 207 | struct sdei_event *event; |
| 208 | struct sdei_registered_event *reg; |
| 209 | |
| 210 | lockdep_assert_held(&sdei_events_lock); |
| 211 | |
| 212 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
| 213 | if (!event) |
| 214 | return ERR_PTR(-ENOMEM); |
| 215 | |
| 216 | INIT_LIST_HEAD(&event->list); |
| 217 | event->event_num = event_num; |
| 218 | |
| 219 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY, |
| 220 | &result); |
| 221 | if (err) { |
| 222 | kfree(event); |
| 223 | return ERR_PTR(err); |
| 224 | } |
| 225 | event->priority = result; |
| 226 | |
| 227 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE, |
| 228 | &result); |
| 229 | if (err) { |
| 230 | kfree(event); |
| 231 | return ERR_PTR(err); |
| 232 | } |
| 233 | event->type = result; |
| 234 | |
| 235 | if (event->type == SDEI_EVENT_TYPE_SHARED) { |
| 236 | reg = kzalloc(sizeof(*reg), GFP_KERNEL); |
| 237 | if (!reg) { |
| 238 | kfree(event); |
| 239 | return ERR_PTR(-ENOMEM); |
| 240 | } |
| 241 | |
| 242 | reg->event_num = event_num; |
| 243 | reg->priority = event->priority; |
| 244 | |
| 245 | reg->callback = cb; |
| 246 | reg->callback_arg = cb_arg; |
| 247 | event->registered = reg; |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 248 | } else { |
| 249 | int cpu; |
| 250 | struct sdei_registered_event __percpu *regs; |
| 251 | |
| 252 | regs = alloc_percpu(struct sdei_registered_event); |
| 253 | if (!regs) { |
| 254 | kfree(event); |
| 255 | return ERR_PTR(-ENOMEM); |
| 256 | } |
| 257 | |
| 258 | for_each_possible_cpu(cpu) { |
| 259 | reg = per_cpu_ptr(regs, cpu); |
| 260 | |
| 261 | reg->event_num = event->event_num; |
| 262 | reg->priority = event->priority; |
| 263 | reg->callback = cb; |
| 264 | reg->callback_arg = cb_arg; |
| 265 | } |
| 266 | |
| 267 | event->private_registered = regs; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 268 | } |
| 269 | |
| 270 | if (sdei_event_find(event_num)) { |
| 271 | kfree(event->registered); |
| 272 | kfree(event); |
| 273 | event = ERR_PTR(-EBUSY); |
| 274 | } else { |
| 275 | spin_lock(&sdei_list_lock); |
| 276 | list_add(&event->list, &sdei_list); |
| 277 | spin_unlock(&sdei_list_lock); |
| 278 | } |
| 279 | |
| 280 | return event; |
| 281 | } |
| 282 | |
| 283 | static void sdei_event_destroy(struct sdei_event *event) |
| 284 | { |
| 285 | lockdep_assert_held(&sdei_events_lock); |
| 286 | |
| 287 | spin_lock(&sdei_list_lock); |
| 288 | list_del(&event->list); |
| 289 | spin_unlock(&sdei_list_lock); |
| 290 | |
| 291 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 292 | kfree(event->registered); |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 293 | else |
| 294 | free_percpu(event->private_registered); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 295 | |
| 296 | kfree(event); |
| 297 | } |
| 298 | |
| 299 | static int sdei_api_get_version(u64 *version) |
| 300 | { |
| 301 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_VERSION, 0, 0, 0, 0, 0, version); |
| 302 | } |
| 303 | |
| 304 | int sdei_mask_local_cpu(void) |
| 305 | { |
| 306 | int err; |
| 307 | |
| 308 | WARN_ON_ONCE(preemptible()); |
| 309 | |
| 310 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL); |
| 311 | if (err && err != -EIO) { |
| 312 | pr_warn_once("failed to mask CPU[%u]: %d\n", |
| 313 | smp_processor_id(), err); |
| 314 | return err; |
| 315 | } |
| 316 | |
| 317 | return 0; |
| 318 | } |
| 319 | |
| 320 | static void _ipi_mask_cpu(void *ignored) |
| 321 | { |
| 322 | sdei_mask_local_cpu(); |
| 323 | } |
| 324 | |
| 325 | int sdei_unmask_local_cpu(void) |
| 326 | { |
| 327 | int err; |
| 328 | |
| 329 | WARN_ON_ONCE(preemptible()); |
| 330 | |
| 331 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL); |
| 332 | if (err && err != -EIO) { |
| 333 | pr_warn_once("failed to unmask CPU[%u]: %d\n", |
| 334 | smp_processor_id(), err); |
| 335 | return err; |
| 336 | } |
| 337 | |
| 338 | return 0; |
| 339 | } |
| 340 | |
| 341 | static void _ipi_unmask_cpu(void *ignored) |
| 342 | { |
| 343 | sdei_unmask_local_cpu(); |
| 344 | } |
| 345 | |
| 346 | static void _ipi_private_reset(void *ignored) |
| 347 | { |
| 348 | int err; |
| 349 | |
| 350 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0, |
| 351 | NULL); |
| 352 | if (err && err != -EIO) |
| 353 | pr_warn_once("failed to reset CPU[%u]: %d\n", |
| 354 | smp_processor_id(), err); |
| 355 | } |
| 356 | |
| 357 | static int sdei_api_shared_reset(void) |
| 358 | { |
| 359 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_SHARED_RESET, 0, 0, 0, 0, 0, |
| 360 | NULL); |
| 361 | } |
| 362 | |
| 363 | static void sdei_mark_interface_broken(void) |
| 364 | { |
| 365 | pr_err("disabling SDEI firmware interface\n"); |
| 366 | on_each_cpu(&_ipi_mask_cpu, NULL, true); |
| 367 | sdei_firmware_call = NULL; |
| 368 | } |
| 369 | |
| 370 | static int sdei_platform_reset(void) |
| 371 | { |
| 372 | int err; |
| 373 | |
| 374 | on_each_cpu(&_ipi_private_reset, NULL, true); |
| 375 | err = sdei_api_shared_reset(); |
| 376 | if (err) { |
| 377 | pr_err("Failed to reset platform: %d\n", err); |
| 378 | sdei_mark_interface_broken(); |
| 379 | } |
| 380 | |
| 381 | return err; |
| 382 | } |
| 383 | |
| 384 | static int sdei_api_event_enable(u32 event_num) |
| 385 | { |
| 386 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_ENABLE, event_num, 0, 0, 0, |
| 387 | 0, NULL); |
| 388 | } |
| 389 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 390 | /* Called directly by the hotplug callbacks */ |
| 391 | static void _local_event_enable(void *data) |
| 392 | { |
| 393 | int err; |
| 394 | struct sdei_crosscall_args *arg = data; |
| 395 | |
| 396 | WARN_ON_ONCE(preemptible()); |
| 397 | |
| 398 | err = sdei_api_event_enable(arg->event->event_num); |
| 399 | |
| 400 | sdei_cross_call_return(arg, err); |
| 401 | } |
| 402 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 403 | int sdei_event_enable(u32 event_num) |
| 404 | { |
| 405 | int err = -EINVAL; |
| 406 | struct sdei_event *event; |
| 407 | |
| 408 | mutex_lock(&sdei_events_lock); |
| 409 | event = sdei_event_find(event_num); |
| 410 | if (!event) { |
| 411 | mutex_unlock(&sdei_events_lock); |
| 412 | return -ENOENT; |
| 413 | } |
| 414 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 415 | spin_lock(&sdei_list_lock); |
| 416 | event->reenable = true; |
| 417 | spin_unlock(&sdei_list_lock); |
| 418 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 419 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 420 | err = sdei_api_event_enable(event->event_num); |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 421 | else |
| 422 | err = sdei_do_cross_call(_local_event_enable, event); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 423 | mutex_unlock(&sdei_events_lock); |
| 424 | |
| 425 | return err; |
| 426 | } |
| 427 | EXPORT_SYMBOL(sdei_event_enable); |
| 428 | |
| 429 | static int sdei_api_event_disable(u32 event_num) |
| 430 | { |
| 431 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_DISABLE, event_num, 0, 0, |
| 432 | 0, 0, NULL); |
| 433 | } |
| 434 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 435 | static void _ipi_event_disable(void *data) |
| 436 | { |
| 437 | int err; |
| 438 | struct sdei_crosscall_args *arg = data; |
| 439 | |
| 440 | err = sdei_api_event_disable(arg->event->event_num); |
| 441 | |
| 442 | sdei_cross_call_return(arg, err); |
| 443 | } |
| 444 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 445 | int sdei_event_disable(u32 event_num) |
| 446 | { |
| 447 | int err = -EINVAL; |
| 448 | struct sdei_event *event; |
| 449 | |
| 450 | mutex_lock(&sdei_events_lock); |
| 451 | event = sdei_event_find(event_num); |
| 452 | if (!event) { |
| 453 | mutex_unlock(&sdei_events_lock); |
| 454 | return -ENOENT; |
| 455 | } |
| 456 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 457 | spin_lock(&sdei_list_lock); |
| 458 | event->reenable = false; |
| 459 | spin_unlock(&sdei_list_lock); |
| 460 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 461 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 462 | err = sdei_api_event_disable(event->event_num); |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 463 | else |
| 464 | err = sdei_do_cross_call(_ipi_event_disable, event); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 465 | mutex_unlock(&sdei_events_lock); |
| 466 | |
| 467 | return err; |
| 468 | } |
| 469 | EXPORT_SYMBOL(sdei_event_disable); |
| 470 | |
| 471 | static int sdei_api_event_unregister(u32 event_num) |
| 472 | { |
| 473 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_UNREGISTER, event_num, 0, |
| 474 | 0, 0, 0, NULL); |
| 475 | } |
| 476 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 477 | /* Called directly by the hotplug callbacks */ |
| 478 | static void _local_event_unregister(void *data) |
| 479 | { |
| 480 | int err; |
| 481 | struct sdei_crosscall_args *arg = data; |
| 482 | |
| 483 | WARN_ON_ONCE(preemptible()); |
| 484 | |
| 485 | err = sdei_api_event_unregister(arg->event->event_num); |
| 486 | |
| 487 | sdei_cross_call_return(arg, err); |
| 488 | } |
| 489 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 490 | static int _sdei_event_unregister(struct sdei_event *event) |
| 491 | { |
| 492 | lockdep_assert_held(&sdei_events_lock); |
| 493 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 494 | spin_lock(&sdei_list_lock); |
| 495 | event->reregister = false; |
| 496 | event->reenable = false; |
| 497 | spin_unlock(&sdei_list_lock); |
| 498 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 499 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 500 | return sdei_api_event_unregister(event->event_num); |
| 501 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 502 | return sdei_do_cross_call(_local_event_unregister, event); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 503 | } |
| 504 | |
| 505 | int sdei_event_unregister(u32 event_num) |
| 506 | { |
| 507 | int err; |
| 508 | struct sdei_event *event; |
| 509 | |
| 510 | WARN_ON(in_nmi()); |
| 511 | |
| 512 | mutex_lock(&sdei_events_lock); |
| 513 | event = sdei_event_find(event_num); |
| 514 | do { |
| 515 | if (!event) { |
| 516 | pr_warn("Event %u not registered\n", event_num); |
| 517 | err = -ENOENT; |
| 518 | break; |
| 519 | } |
| 520 | |
| 521 | err = _sdei_event_unregister(event); |
| 522 | if (err) |
| 523 | break; |
| 524 | |
| 525 | sdei_event_destroy(event); |
| 526 | } while (0); |
| 527 | mutex_unlock(&sdei_events_lock); |
| 528 | |
| 529 | return err; |
| 530 | } |
| 531 | EXPORT_SYMBOL(sdei_event_unregister); |
| 532 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 533 | /* |
| 534 | * unregister events, but don't destroy them as they are re-registered by |
| 535 | * sdei_reregister_shared(). |
| 536 | */ |
| 537 | static int sdei_unregister_shared(void) |
| 538 | { |
| 539 | int err = 0; |
| 540 | struct sdei_event *event; |
| 541 | |
| 542 | mutex_lock(&sdei_events_lock); |
| 543 | spin_lock(&sdei_list_lock); |
| 544 | list_for_each_entry(event, &sdei_list, list) { |
| 545 | if (event->type != SDEI_EVENT_TYPE_SHARED) |
| 546 | continue; |
| 547 | |
| 548 | err = _sdei_event_unregister(event); |
| 549 | if (err) |
| 550 | break; |
| 551 | } |
| 552 | spin_unlock(&sdei_list_lock); |
| 553 | mutex_unlock(&sdei_events_lock); |
| 554 | |
| 555 | return err; |
| 556 | } |
| 557 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 558 | static int sdei_api_event_register(u32 event_num, unsigned long entry_point, |
| 559 | void *arg, u64 flags, u64 affinity) |
| 560 | { |
| 561 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_REGISTER, event_num, |
| 562 | (unsigned long)entry_point, (unsigned long)arg, |
| 563 | flags, affinity, NULL); |
| 564 | } |
| 565 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 566 | /* Called directly by the hotplug callbacks */ |
| 567 | static void _local_event_register(void *data) |
| 568 | { |
| 569 | int err; |
| 570 | struct sdei_registered_event *reg; |
| 571 | struct sdei_crosscall_args *arg = data; |
| 572 | |
| 573 | WARN_ON(preemptible()); |
| 574 | |
| 575 | reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id()); |
| 576 | err = sdei_api_event_register(arg->event->event_num, sdei_entry_point, |
| 577 | reg, 0, 0); |
| 578 | |
| 579 | sdei_cross_call_return(arg, err); |
| 580 | } |
| 581 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 582 | static int _sdei_event_register(struct sdei_event *event) |
| 583 | { |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 584 | int err; |
| 585 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 586 | lockdep_assert_held(&sdei_events_lock); |
| 587 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 588 | spin_lock(&sdei_list_lock); |
| 589 | event->reregister = true; |
| 590 | spin_unlock(&sdei_list_lock); |
| 591 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 592 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 593 | return sdei_api_event_register(event->event_num, |
| 594 | sdei_entry_point, |
| 595 | event->registered, |
| 596 | SDEI_EVENT_REGISTER_RM_ANY, 0); |
| 597 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 598 | |
| 599 | err = sdei_do_cross_call(_local_event_register, event); |
| 600 | if (err) { |
| 601 | spin_lock(&sdei_list_lock); |
| 602 | event->reregister = false; |
| 603 | event->reenable = false; |
| 604 | spin_unlock(&sdei_list_lock); |
| 605 | |
| 606 | sdei_do_cross_call(_local_event_unregister, event); |
| 607 | } |
| 608 | |
| 609 | return err; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 610 | } |
| 611 | |
| 612 | int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg) |
| 613 | { |
| 614 | int err; |
| 615 | struct sdei_event *event; |
| 616 | |
| 617 | WARN_ON(in_nmi()); |
| 618 | |
| 619 | mutex_lock(&sdei_events_lock); |
| 620 | do { |
| 621 | if (sdei_event_find(event_num)) { |
| 622 | pr_warn("Event %u already registered\n", event_num); |
| 623 | err = -EBUSY; |
| 624 | break; |
| 625 | } |
| 626 | |
| 627 | event = sdei_event_create(event_num, cb, arg); |
| 628 | if (IS_ERR(event)) { |
| 629 | err = PTR_ERR(event); |
| 630 | pr_warn("Failed to create event %u: %d\n", event_num, |
| 631 | err); |
| 632 | break; |
| 633 | } |
| 634 | |
| 635 | err = _sdei_event_register(event); |
| 636 | if (err) { |
| 637 | sdei_event_destroy(event); |
| 638 | pr_warn("Failed to register event %u: %d\n", event_num, |
| 639 | err); |
| 640 | } |
| 641 | } while (0); |
| 642 | mutex_unlock(&sdei_events_lock); |
| 643 | |
| 644 | return err; |
| 645 | } |
| 646 | EXPORT_SYMBOL(sdei_event_register); |
| 647 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 648 | static int sdei_reregister_event(struct sdei_event *event) |
| 649 | { |
| 650 | int err; |
| 651 | |
| 652 | lockdep_assert_held(&sdei_events_lock); |
| 653 | |
| 654 | err = _sdei_event_register(event); |
| 655 | if (err) { |
| 656 | pr_err("Failed to re-register event %u\n", event->event_num); |
| 657 | sdei_event_destroy(event); |
| 658 | return err; |
| 659 | } |
| 660 | |
| 661 | if (event->reenable) { |
| 662 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 663 | err = sdei_api_event_enable(event->event_num); |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 664 | else |
| 665 | err = sdei_do_cross_call(_local_event_enable, event); |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 666 | } |
| 667 | |
| 668 | if (err) |
| 669 | pr_err("Failed to re-enable event %u\n", event->event_num); |
| 670 | |
| 671 | return err; |
| 672 | } |
| 673 | |
| 674 | static int sdei_reregister_shared(void) |
| 675 | { |
| 676 | int err = 0; |
| 677 | struct sdei_event *event; |
| 678 | |
| 679 | mutex_lock(&sdei_events_lock); |
| 680 | spin_lock(&sdei_list_lock); |
| 681 | list_for_each_entry(event, &sdei_list, list) { |
| 682 | if (event->type != SDEI_EVENT_TYPE_SHARED) |
| 683 | continue; |
| 684 | |
| 685 | if (event->reregister) { |
| 686 | err = sdei_reregister_event(event); |
| 687 | if (err) |
| 688 | break; |
| 689 | } |
| 690 | } |
| 691 | spin_unlock(&sdei_list_lock); |
| 692 | mutex_unlock(&sdei_events_lock); |
| 693 | |
| 694 | return err; |
| 695 | } |
| 696 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 697 | static int sdei_cpuhp_down(unsigned int cpu) |
| 698 | { |
| 699 | struct sdei_event *event; |
| 700 | struct sdei_crosscall_args arg; |
| 701 | |
| 702 | /* un-register private events */ |
| 703 | spin_lock(&sdei_list_lock); |
| 704 | list_for_each_entry(event, &sdei_list, list) { |
| 705 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 706 | continue; |
| 707 | |
| 708 | CROSSCALL_INIT(arg, event); |
| 709 | /* call the cross-call function locally... */ |
| 710 | _local_event_unregister(&arg); |
| 711 | if (arg.first_error) |
| 712 | pr_err("Failed to unregister event %u: %d\n", |
| 713 | event->event_num, arg.first_error); |
| 714 | } |
| 715 | spin_unlock(&sdei_list_lock); |
| 716 | |
| 717 | return sdei_mask_local_cpu(); |
| 718 | } |
| 719 | |
| 720 | static int sdei_cpuhp_up(unsigned int cpu) |
| 721 | { |
| 722 | struct sdei_event *event; |
| 723 | struct sdei_crosscall_args arg; |
| 724 | |
| 725 | /* re-register/enable private events */ |
| 726 | spin_lock(&sdei_list_lock); |
| 727 | list_for_each_entry(event, &sdei_list, list) { |
| 728 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
| 729 | continue; |
| 730 | |
| 731 | if (event->reregister) { |
| 732 | CROSSCALL_INIT(arg, event); |
| 733 | /* call the cross-call function locally... */ |
| 734 | _local_event_register(&arg); |
| 735 | if (arg.first_error) |
| 736 | pr_err("Failed to re-register event %u: %d\n", |
| 737 | event->event_num, arg.first_error); |
| 738 | } |
| 739 | |
| 740 | if (event->reenable) { |
| 741 | CROSSCALL_INIT(arg, event); |
| 742 | _local_event_enable(&arg); |
| 743 | if (arg.first_error) |
| 744 | pr_err("Failed to re-enable event %u: %d\n", |
| 745 | event->event_num, arg.first_error); |
| 746 | } |
| 747 | } |
| 748 | spin_unlock(&sdei_list_lock); |
| 749 | |
| 750 | return sdei_unmask_local_cpu(); |
| 751 | } |
| 752 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 753 | /* When entering idle, mask/unmask events for this cpu */ |
| 754 | static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action, |
| 755 | void *data) |
| 756 | { |
| 757 | int rv; |
| 758 | |
| 759 | switch (action) { |
| 760 | case CPU_PM_ENTER: |
| 761 | rv = sdei_mask_local_cpu(); |
| 762 | break; |
| 763 | case CPU_PM_EXIT: |
| 764 | case CPU_PM_ENTER_FAILED: |
| 765 | rv = sdei_unmask_local_cpu(); |
| 766 | break; |
| 767 | default: |
| 768 | return NOTIFY_DONE; |
| 769 | } |
| 770 | |
| 771 | if (rv) |
| 772 | return notifier_from_errno(rv); |
| 773 | |
| 774 | return NOTIFY_OK; |
| 775 | } |
| 776 | |
| 777 | static struct notifier_block sdei_pm_nb = { |
| 778 | .notifier_call = sdei_pm_notifier, |
| 779 | }; |
| 780 | |
| 781 | static int sdei_device_suspend(struct device *dev) |
| 782 | { |
| 783 | on_each_cpu(_ipi_mask_cpu, NULL, true); |
| 784 | |
| 785 | return 0; |
| 786 | } |
| 787 | |
| 788 | static int sdei_device_resume(struct device *dev) |
| 789 | { |
| 790 | on_each_cpu(_ipi_unmask_cpu, NULL, true); |
| 791 | |
| 792 | return 0; |
| 793 | } |
| 794 | |
| 795 | /* |
| 796 | * We need all events to be reregistered when we resume from hibernate. |
| 797 | * |
| 798 | * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister |
| 799 | * events during freeze, then re-register and re-enable them during thaw |
| 800 | * and restore. |
| 801 | */ |
| 802 | static int sdei_device_freeze(struct device *dev) |
| 803 | { |
| 804 | int err; |
| 805 | |
James Morse | f92b546 | 2018-01-08 15:38:14 +0000 | [diff] [blame] | 806 | /* unregister private events */ |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 807 | cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); |
| 808 | |
| 809 | err = sdei_unregister_shared(); |
| 810 | if (err) |
| 811 | return err; |
| 812 | |
| 813 | return 0; |
| 814 | } |
| 815 | |
| 816 | static int sdei_device_thaw(struct device *dev) |
| 817 | { |
| 818 | int err; |
| 819 | |
| 820 | /* re-register shared events */ |
| 821 | err = sdei_reregister_shared(); |
| 822 | if (err) { |
| 823 | pr_warn("Failed to re-register shared events...\n"); |
| 824 | sdei_mark_interface_broken(); |
| 825 | return err; |
| 826 | } |
| 827 | |
| 828 | err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", |
| 829 | &sdei_cpuhp_up, &sdei_cpuhp_down); |
| 830 | if (err) |
| 831 | pr_warn("Failed to re-register CPU hotplug notifier...\n"); |
| 832 | |
| 833 | return err; |
| 834 | } |
| 835 | |
| 836 | static int sdei_device_restore(struct device *dev) |
| 837 | { |
| 838 | int err; |
| 839 | |
| 840 | err = sdei_platform_reset(); |
| 841 | if (err) |
| 842 | return err; |
| 843 | |
| 844 | return sdei_device_thaw(dev); |
| 845 | } |
| 846 | |
| 847 | static const struct dev_pm_ops sdei_pm_ops = { |
| 848 | .suspend = sdei_device_suspend, |
| 849 | .resume = sdei_device_resume, |
| 850 | .freeze = sdei_device_freeze, |
| 851 | .thaw = sdei_device_thaw, |
| 852 | .restore = sdei_device_restore, |
| 853 | }; |
| 854 | |
| 855 | /* |
| 856 | * Mask all CPUs and unregister all events on panic, reboot or kexec. |
| 857 | */ |
| 858 | static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action, |
| 859 | void *data) |
| 860 | { |
| 861 | /* |
| 862 | * We are going to reset the interface, after this there is no point |
| 863 | * doing work when we take CPUs offline. |
| 864 | */ |
| 865 | cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); |
| 866 | |
| 867 | sdei_platform_reset(); |
| 868 | |
| 869 | return NOTIFY_OK; |
| 870 | } |
| 871 | |
| 872 | static struct notifier_block sdei_reboot_nb = { |
| 873 | .notifier_call = sdei_reboot_notifier, |
| 874 | }; |
| 875 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 876 | static void sdei_smccc_smc(unsigned long function_id, |
| 877 | unsigned long arg0, unsigned long arg1, |
| 878 | unsigned long arg2, unsigned long arg3, |
| 879 | unsigned long arg4, struct arm_smccc_res *res) |
| 880 | { |
| 881 | arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); |
| 882 | } |
Xiongfeng Wang | 2f1d4e2 | 2019-04-26 10:16:36 +0800 | [diff] [blame] | 883 | NOKPROBE_SYMBOL(sdei_smccc_smc); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 884 | |
| 885 | static void sdei_smccc_hvc(unsigned long function_id, |
| 886 | unsigned long arg0, unsigned long arg1, |
| 887 | unsigned long arg2, unsigned long arg3, |
| 888 | unsigned long arg4, struct arm_smccc_res *res) |
| 889 | { |
| 890 | arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); |
| 891 | } |
Xiongfeng Wang | 2f1d4e2 | 2019-04-26 10:16:36 +0800 | [diff] [blame] | 892 | NOKPROBE_SYMBOL(sdei_smccc_hvc); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 893 | |
James Morse | f96935d | 2019-01-29 18:49:01 +0000 | [diff] [blame] | 894 | int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb, |
| 895 | sdei_event_callback *critical_cb) |
| 896 | { |
| 897 | int err; |
| 898 | u64 result; |
| 899 | u32 event_num; |
| 900 | sdei_event_callback *cb; |
| 901 | |
| 902 | if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) |
| 903 | return -EOPNOTSUPP; |
| 904 | |
| 905 | event_num = ghes->generic->notify.vector; |
| 906 | if (event_num == 0) { |
| 907 | /* |
| 908 | * Event 0 is reserved by the specification for |
| 909 | * SDEI_EVENT_SIGNAL. |
| 910 | */ |
| 911 | return -EINVAL; |
| 912 | } |
| 913 | |
| 914 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY, |
| 915 | &result); |
| 916 | if (err) |
| 917 | return err; |
| 918 | |
| 919 | if (result == SDEI_EVENT_PRIORITY_CRITICAL) |
| 920 | cb = critical_cb; |
| 921 | else |
| 922 | cb = normal_cb; |
| 923 | |
| 924 | err = sdei_event_register(event_num, cb, ghes); |
| 925 | if (!err) |
| 926 | err = sdei_event_enable(event_num); |
| 927 | |
| 928 | return err; |
| 929 | } |
| 930 | |
| 931 | int sdei_unregister_ghes(struct ghes *ghes) |
| 932 | { |
| 933 | int i; |
| 934 | int err; |
| 935 | u32 event_num = ghes->generic->notify.vector; |
| 936 | |
| 937 | might_sleep(); |
| 938 | |
| 939 | if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) |
| 940 | return -EOPNOTSUPP; |
| 941 | |
| 942 | /* |
| 943 | * The event may be running on another CPU. Disable it |
| 944 | * to stop new events, then try to unregister a few times. |
| 945 | */ |
| 946 | err = sdei_event_disable(event_num); |
| 947 | if (err) |
| 948 | return err; |
| 949 | |
| 950 | for (i = 0; i < 3; i++) { |
| 951 | err = sdei_event_unregister(event_num); |
| 952 | if (err != -EINPROGRESS) |
| 953 | break; |
| 954 | |
| 955 | schedule(); |
| 956 | } |
| 957 | |
| 958 | return err; |
| 959 | } |
| 960 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 961 | static int sdei_get_conduit(struct platform_device *pdev) |
| 962 | { |
| 963 | const char *method; |
| 964 | struct device_node *np = pdev->dev.of_node; |
| 965 | |
| 966 | sdei_firmware_call = NULL; |
| 967 | if (np) { |
| 968 | if (of_property_read_string(np, "method", &method)) { |
| 969 | pr_warn("missing \"method\" property\n"); |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 970 | return SMCCC_CONDUIT_NONE; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 971 | } |
| 972 | |
| 973 | if (!strcmp("hvc", method)) { |
| 974 | sdei_firmware_call = &sdei_smccc_hvc; |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 975 | return SMCCC_CONDUIT_HVC; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 976 | } else if (!strcmp("smc", method)) { |
| 977 | sdei_firmware_call = &sdei_smccc_smc; |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 978 | return SMCCC_CONDUIT_SMC; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 979 | } |
| 980 | |
| 981 | pr_warn("invalid \"method\" property: %s\n", method); |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 982 | } else if (IS_ENABLED(CONFIG_ACPI) && !acpi_disabled) { |
| 983 | if (acpi_psci_use_hvc()) { |
| 984 | sdei_firmware_call = &sdei_smccc_hvc; |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 985 | return SMCCC_CONDUIT_HVC; |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 986 | } else { |
| 987 | sdei_firmware_call = &sdei_smccc_smc; |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 988 | return SMCCC_CONDUIT_SMC; |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 989 | } |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 990 | } |
| 991 | |
Mark Rutland | e6ea465 | 2019-08-09 14:22:44 +0100 | [diff] [blame] | 992 | return SMCCC_CONDUIT_NONE; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 993 | } |
| 994 | |
| 995 | static int sdei_probe(struct platform_device *pdev) |
| 996 | { |
| 997 | int err; |
| 998 | u64 ver = 0; |
| 999 | int conduit; |
| 1000 | |
| 1001 | conduit = sdei_get_conduit(pdev); |
| 1002 | if (!sdei_firmware_call) |
| 1003 | return 0; |
| 1004 | |
| 1005 | err = sdei_api_get_version(&ver); |
| 1006 | if (err == -EOPNOTSUPP) |
| 1007 | pr_err("advertised but not implemented in platform firmware\n"); |
| 1008 | if (err) { |
| 1009 | pr_err("Failed to get SDEI version: %d\n", err); |
| 1010 | sdei_mark_interface_broken(); |
| 1011 | return err; |
| 1012 | } |
| 1013 | |
| 1014 | pr_info("SDEIv%d.%d (0x%x) detected in firmware.\n", |
| 1015 | (int)SDEI_VERSION_MAJOR(ver), (int)SDEI_VERSION_MINOR(ver), |
| 1016 | (int)SDEI_VERSION_VENDOR(ver)); |
| 1017 | |
| 1018 | if (SDEI_VERSION_MAJOR(ver) != 1) { |
| 1019 | pr_warn("Conflicting SDEI version detected.\n"); |
| 1020 | sdei_mark_interface_broken(); |
| 1021 | return -EINVAL; |
| 1022 | } |
| 1023 | |
| 1024 | err = sdei_platform_reset(); |
| 1025 | if (err) |
| 1026 | return err; |
| 1027 | |
| 1028 | sdei_entry_point = sdei_arch_get_entry_point(conduit); |
| 1029 | if (!sdei_entry_point) { |
| 1030 | /* Not supported due to hardware or boot configuration */ |
| 1031 | sdei_mark_interface_broken(); |
| 1032 | return 0; |
| 1033 | } |
| 1034 | |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 1035 | err = cpu_pm_register_notifier(&sdei_pm_nb); |
| 1036 | if (err) { |
| 1037 | pr_warn("Failed to register CPU PM notifier...\n"); |
| 1038 | goto error; |
| 1039 | } |
| 1040 | |
| 1041 | err = register_reboot_notifier(&sdei_reboot_nb); |
| 1042 | if (err) { |
| 1043 | pr_warn("Failed to register reboot notifier...\n"); |
| 1044 | goto remove_cpupm; |
| 1045 | } |
| 1046 | |
| 1047 | err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", |
| 1048 | &sdei_cpuhp_up, &sdei_cpuhp_down); |
| 1049 | if (err) { |
| 1050 | pr_warn("Failed to register CPU hotplug notifier...\n"); |
| 1051 | goto remove_reboot; |
| 1052 | } |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1053 | |
| 1054 | return 0; |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 1055 | |
| 1056 | remove_reboot: |
| 1057 | unregister_reboot_notifier(&sdei_reboot_nb); |
| 1058 | |
| 1059 | remove_cpupm: |
| 1060 | cpu_pm_unregister_notifier(&sdei_pm_nb); |
| 1061 | |
| 1062 | error: |
| 1063 | sdei_mark_interface_broken(); |
| 1064 | return err; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1065 | } |
| 1066 | |
| 1067 | static const struct of_device_id sdei_of_match[] = { |
| 1068 | { .compatible = "arm,sdei-1.0" }, |
| 1069 | {} |
| 1070 | }; |
| 1071 | |
| 1072 | static struct platform_driver sdei_driver = { |
| 1073 | .driver = { |
| 1074 | .name = "sdei", |
James Morse | da35182 | 2018-01-08 15:38:13 +0000 | [diff] [blame] | 1075 | .pm = &sdei_pm_ops, |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1076 | .of_match_table = sdei_of_match, |
| 1077 | }, |
| 1078 | .probe = sdei_probe, |
| 1079 | }; |
| 1080 | |
| 1081 | static bool __init sdei_present_dt(void) |
| 1082 | { |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1083 | struct device_node *np, *fw_np; |
| 1084 | |
| 1085 | fw_np = of_find_node_by_name(NULL, "firmware"); |
| 1086 | if (!fw_np) |
| 1087 | return false; |
| 1088 | |
| 1089 | np = of_find_matching_node(fw_np, sdei_of_match); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1090 | if (!np) |
| 1091 | return false; |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1092 | of_node_put(np); |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1093 | |
| 1094 | return true; |
| 1095 | } |
| 1096 | |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 1097 | static bool __init sdei_present_acpi(void) |
| 1098 | { |
| 1099 | acpi_status status; |
| 1100 | struct platform_device *pdev; |
| 1101 | struct acpi_table_header *sdei_table_header; |
| 1102 | |
| 1103 | if (acpi_disabled) |
| 1104 | return false; |
| 1105 | |
| 1106 | status = acpi_get_table(ACPI_SIG_SDEI, 0, &sdei_table_header); |
| 1107 | if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { |
| 1108 | const char *msg = acpi_format_exception(status); |
| 1109 | |
| 1110 | pr_info("Failed to get ACPI:SDEI table, %s\n", msg); |
| 1111 | } |
| 1112 | if (ACPI_FAILURE(status)) |
| 1113 | return false; |
| 1114 | |
| 1115 | pdev = platform_device_register_simple(sdei_driver.driver.name, 0, NULL, |
| 1116 | 0); |
| 1117 | if (IS_ERR(pdev)) |
| 1118 | return false; |
| 1119 | |
| 1120 | return true; |
| 1121 | } |
| 1122 | |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1123 | static int __init sdei_init(void) |
| 1124 | { |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 1125 | if (sdei_present_dt() || sdei_present_acpi()) |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1126 | platform_driver_register(&sdei_driver); |
| 1127 | |
| 1128 | return 0; |
| 1129 | } |
| 1130 | |
James Morse | 677a60b | 2018-01-08 15:38:16 +0000 | [diff] [blame] | 1131 | /* |
| 1132 | * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register |
| 1133 | * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised |
| 1134 | * by device_initcall(). We want to be called in the middle. |
| 1135 | */ |
James Morse | ad6eb31 | 2018-01-08 15:38:09 +0000 | [diff] [blame] | 1136 | subsys_initcall_sync(sdei_init); |
| 1137 | |
| 1138 | int sdei_event_handler(struct pt_regs *regs, |
| 1139 | struct sdei_registered_event *arg) |
| 1140 | { |
| 1141 | int err; |
| 1142 | mm_segment_t orig_addr_limit; |
| 1143 | u32 event_num = arg->event_num; |
| 1144 | |
| 1145 | orig_addr_limit = get_fs(); |
| 1146 | set_fs(USER_DS); |
| 1147 | |
| 1148 | err = arg->callback(event_num, regs, arg->callback_arg); |
| 1149 | if (err) |
| 1150 | pr_err_ratelimited("event %u on CPU %u failed with error: %d\n", |
| 1151 | event_num, smp_processor_id(), err); |
| 1152 | |
| 1153 | set_fs(orig_addr_limit); |
| 1154 | |
| 1155 | return err; |
| 1156 | } |
| 1157 | NOKPROBE_SYMBOL(sdei_event_handler); |