Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved. |
| 7 | * Copyright (C) 2013 Imagination Technologies Ltd. |
| 8 | */ |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/device.h> |
| 11 | #include <linux/fs.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/export.h> |
| 14 | |
| 15 | #include <asm/mipsregs.h> |
| 16 | #include <asm/mipsmtregs.h> |
| 17 | #include <asm/mips_mt.h> |
| 18 | #include <asm/vpe.h> |
| 19 | |
| 20 | static int major; |
| 21 | |
| 22 | /* The number of TCs and VPEs physically available on the core */ |
| 23 | static int hw_tcs, hw_vpes; |
| 24 | |
| 25 | /* We are prepared so configure and start the VPE... */ |
| 26 | int vpe_run(struct vpe *v) |
| 27 | { |
| 28 | unsigned long flags, val, dmt_flag; |
Steven J. Hill | 5792bf6 | 2014-01-01 16:35:32 +0100 | [diff] [blame] | 29 | struct vpe_notifications *notifier; |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 30 | unsigned int vpeflags; |
| 31 | struct tc *t; |
| 32 | |
| 33 | /* check we are the Master VPE */ |
| 34 | local_irq_save(flags); |
| 35 | val = read_c0_vpeconf0(); |
| 36 | if (!(val & VPECONF0_MVP)) { |
| 37 | pr_warn("VPE loader: only Master VPE's are able to config MT\n"); |
| 38 | local_irq_restore(flags); |
| 39 | |
| 40 | return -1; |
| 41 | } |
| 42 | |
| 43 | dmt_flag = dmt(); |
| 44 | vpeflags = dvpe(); |
| 45 | |
| 46 | if (list_empty(&v->tc)) { |
| 47 | evpe(vpeflags); |
| 48 | emt(dmt_flag); |
| 49 | local_irq_restore(flags); |
| 50 | |
| 51 | pr_warn("VPE loader: No TC's associated with VPE %d\n", |
| 52 | v->minor); |
| 53 | |
| 54 | return -ENOEXEC; |
| 55 | } |
| 56 | |
| 57 | t = list_first_entry(&v->tc, struct tc, tc); |
| 58 | |
| 59 | /* Put MVPE's into 'configuration state' */ |
| 60 | set_c0_mvpcontrol(MVPCONTROL_VPC); |
| 61 | |
| 62 | settc(t->index); |
| 63 | |
| 64 | /* should check it is halted, and not activated */ |
| 65 | if ((read_tc_c0_tcstatus() & TCSTATUS_A) || |
| 66 | !(read_tc_c0_tchalt() & TCHALT_H)) { |
| 67 | evpe(vpeflags); |
| 68 | emt(dmt_flag); |
| 69 | local_irq_restore(flags); |
| 70 | |
| 71 | pr_warn("VPE loader: TC %d is already active!\n", |
| 72 | t->index); |
| 73 | |
| 74 | return -ENOEXEC; |
| 75 | } |
| 76 | |
| 77 | /* |
| 78 | * Write the address we want it to start running from in the TCPC |
| 79 | * register. |
| 80 | */ |
| 81 | write_tc_c0_tcrestart((unsigned long)v->__start); |
| 82 | write_tc_c0_tccontext((unsigned long)0); |
| 83 | |
| 84 | /* |
| 85 | * Mark the TC as activated, not interrupt exempt and not dynamically |
| 86 | * allocatable |
| 87 | */ |
| 88 | val = read_tc_c0_tcstatus(); |
| 89 | val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A; |
| 90 | write_tc_c0_tcstatus(val); |
| 91 | |
| 92 | write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H); |
| 93 | |
| 94 | /* |
Randy Dunlap | 91dc288 | 2023-02-19 15:15:25 -0800 | [diff] [blame] | 95 | * We don't pass the memsize here, so VPE programs need to be |
| 96 | * compiled with DFLT_STACK_SIZE and DFLT_HEAP_SIZE defined. |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 97 | */ |
Randy Dunlap | 91dc288 | 2023-02-19 15:15:25 -0800 | [diff] [blame] | 98 | mttgpr(7, 0); |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 99 | mttgpr(6, v->ntcs); |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 100 | |
| 101 | /* set up VPE1 */ |
| 102 | /* |
| 103 | * bind the TC to VPE 1 as late as possible so we only have the final |
| 104 | * VPE registers to set up, and so an EJTAG probe can trigger on it |
| 105 | */ |
| 106 | write_tc_c0_tcbind((read_tc_c0_tcbind() & ~TCBIND_CURVPE) | 1); |
| 107 | |
| 108 | write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~(VPECONF0_VPA)); |
| 109 | |
| 110 | back_to_back_c0_hazard(); |
| 111 | |
| 112 | /* Set up the XTC bit in vpeconf0 to point at our tc */ |
| 113 | write_vpe_c0_vpeconf0((read_vpe_c0_vpeconf0() & ~(VPECONF0_XTC)) |
| 114 | | (t->index << VPECONF0_XTC_SHIFT)); |
| 115 | |
| 116 | back_to_back_c0_hazard(); |
| 117 | |
| 118 | /* enable this VPE */ |
| 119 | write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA); |
| 120 | |
| 121 | /* clear out any left overs from a previous program */ |
| 122 | write_vpe_c0_status(0); |
| 123 | write_vpe_c0_cause(0); |
| 124 | |
| 125 | /* take system out of configuration state */ |
| 126 | clear_c0_mvpcontrol(MVPCONTROL_VPC); |
| 127 | |
| 128 | /* |
Ralf Baechle | b633648 | 2014-05-23 16:29:44 +0200 | [diff] [blame] | 129 | * SMVP kernels manage VPE enable independently, but uniprocessor |
| 130 | * kernels need to turn it on, even if that wasn't the pre-dvpe() state. |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 131 | */ |
| 132 | #ifdef CONFIG_SMP |
| 133 | evpe(vpeflags); |
| 134 | #else |
| 135 | evpe(EVPE_ENABLE); |
| 136 | #endif |
| 137 | emt(dmt_flag); |
| 138 | local_irq_restore(flags); |
| 139 | |
Steven J. Hill | 5792bf6 | 2014-01-01 16:35:32 +0100 | [diff] [blame] | 140 | list_for_each_entry(notifier, &v->notify, list) |
| 141 | notifier->start(VPE_MODULE_MINOR); |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 142 | |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | void cleanup_tc(struct tc *tc) |
| 147 | { |
| 148 | unsigned long flags; |
| 149 | unsigned int mtflags, vpflags; |
| 150 | int tmp; |
| 151 | |
| 152 | local_irq_save(flags); |
| 153 | mtflags = dmt(); |
| 154 | vpflags = dvpe(); |
| 155 | /* Put MVPE's into 'configuration state' */ |
| 156 | set_c0_mvpcontrol(MVPCONTROL_VPC); |
| 157 | |
| 158 | settc(tc->index); |
| 159 | tmp = read_tc_c0_tcstatus(); |
| 160 | |
| 161 | /* mark not allocated and not dynamically allocatable */ |
| 162 | tmp &= ~(TCSTATUS_A | TCSTATUS_DA); |
| 163 | tmp |= TCSTATUS_IXMT; /* interrupt exempt */ |
| 164 | write_tc_c0_tcstatus(tmp); |
| 165 | |
| 166 | write_tc_c0_tchalt(TCHALT_H); |
| 167 | mips_ihb(); |
| 168 | |
| 169 | clear_c0_mvpcontrol(MVPCONTROL_VPC); |
| 170 | evpe(vpflags); |
| 171 | emt(mtflags); |
| 172 | local_irq_restore(flags); |
| 173 | } |
| 174 | |
| 175 | /* module wrapper entry points */ |
| 176 | /* give me a vpe */ |
| 177 | void *vpe_alloc(void) |
| 178 | { |
| 179 | int i; |
| 180 | struct vpe *v; |
| 181 | |
| 182 | /* find a vpe */ |
| 183 | for (i = 1; i < MAX_VPES; i++) { |
| 184 | v = get_vpe(i); |
| 185 | if (v != NULL) { |
| 186 | v->state = VPE_STATE_INUSE; |
| 187 | return v; |
| 188 | } |
| 189 | } |
| 190 | return NULL; |
| 191 | } |
| 192 | EXPORT_SYMBOL(vpe_alloc); |
| 193 | |
| 194 | /* start running from here */ |
| 195 | int vpe_start(void *vpe, unsigned long start) |
| 196 | { |
| 197 | struct vpe *v = vpe; |
| 198 | |
| 199 | v->__start = start; |
| 200 | return vpe_run(v); |
| 201 | } |
| 202 | EXPORT_SYMBOL(vpe_start); |
| 203 | |
| 204 | /* halt it for now */ |
| 205 | int vpe_stop(void *vpe) |
| 206 | { |
| 207 | struct vpe *v = vpe; |
| 208 | struct tc *t; |
| 209 | unsigned int evpe_flags; |
| 210 | |
| 211 | evpe_flags = dvpe(); |
| 212 | |
| 213 | t = list_entry(v->tc.next, struct tc, tc); |
| 214 | if (t != NULL) { |
| 215 | settc(t->index); |
| 216 | write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA); |
| 217 | } |
| 218 | |
| 219 | evpe(evpe_flags); |
| 220 | |
| 221 | return 0; |
| 222 | } |
| 223 | EXPORT_SYMBOL(vpe_stop); |
| 224 | |
| 225 | /* I've done with it thank you */ |
| 226 | int vpe_free(void *vpe) |
| 227 | { |
| 228 | struct vpe *v = vpe; |
| 229 | struct tc *t; |
| 230 | unsigned int evpe_flags; |
| 231 | |
| 232 | t = list_entry(v->tc.next, struct tc, tc); |
| 233 | if (t == NULL) |
| 234 | return -ENOEXEC; |
| 235 | |
| 236 | evpe_flags = dvpe(); |
| 237 | |
| 238 | /* Put MVPE's into 'configuration state' */ |
| 239 | set_c0_mvpcontrol(MVPCONTROL_VPC); |
| 240 | |
| 241 | settc(t->index); |
| 242 | write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA); |
| 243 | |
| 244 | /* halt the TC */ |
| 245 | write_tc_c0_tchalt(TCHALT_H); |
| 246 | mips_ihb(); |
| 247 | |
| 248 | /* mark the TC unallocated */ |
| 249 | write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A); |
| 250 | |
| 251 | v->state = VPE_STATE_UNUSED; |
| 252 | |
| 253 | clear_c0_mvpcontrol(MVPCONTROL_VPC); |
| 254 | evpe(evpe_flags); |
| 255 | |
| 256 | return 0; |
| 257 | } |
| 258 | EXPORT_SYMBOL(vpe_free); |
| 259 | |
| 260 | static ssize_t store_kill(struct device *dev, struct device_attribute *attr, |
| 261 | const char *buf, size_t len) |
| 262 | { |
| 263 | struct vpe *vpe = get_vpe(aprp_cpu_index()); |
| 264 | struct vpe_notifications *notifier; |
| 265 | |
| 266 | list_for_each_entry(notifier, &vpe->notify, list) |
| 267 | notifier->stop(aprp_cpu_index()); |
| 268 | |
| 269 | release_progmem(vpe->load_addr); |
| 270 | cleanup_tc(get_tc(aprp_cpu_index())); |
| 271 | vpe_stop(vpe); |
| 272 | vpe_free(vpe); |
| 273 | |
| 274 | return len; |
| 275 | } |
| 276 | static DEVICE_ATTR(kill, S_IWUSR, NULL, store_kill); |
| 277 | |
| 278 | static ssize_t ntcs_show(struct device *cd, struct device_attribute *attr, |
| 279 | char *buf) |
| 280 | { |
| 281 | struct vpe *vpe = get_vpe(aprp_cpu_index()); |
| 282 | |
| 283 | return sprintf(buf, "%d\n", vpe->ntcs); |
| 284 | } |
| 285 | |
| 286 | static ssize_t ntcs_store(struct device *dev, struct device_attribute *attr, |
| 287 | const char *buf, size_t len) |
| 288 | { |
| 289 | struct vpe *vpe = get_vpe(aprp_cpu_index()); |
| 290 | unsigned long new; |
| 291 | int ret; |
| 292 | |
| 293 | ret = kstrtoul(buf, 0, &new); |
| 294 | if (ret < 0) |
| 295 | return ret; |
| 296 | |
| 297 | if (new == 0 || new > (hw_tcs - aprp_cpu_index())) |
| 298 | return -EINVAL; |
| 299 | |
| 300 | vpe->ntcs = new; |
| 301 | |
| 302 | return len; |
| 303 | } |
| 304 | static DEVICE_ATTR_RW(ntcs); |
| 305 | |
| 306 | static struct attribute *vpe_attrs[] = { |
| 307 | &dev_attr_kill.attr, |
| 308 | &dev_attr_ntcs.attr, |
| 309 | NULL, |
| 310 | }; |
| 311 | ATTRIBUTE_GROUPS(vpe); |
| 312 | |
| 313 | static void vpe_device_release(struct device *cd) |
| 314 | { |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 315 | } |
| 316 | |
| 317 | static struct class vpe_class = { |
| 318 | .name = "vpe", |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 319 | .dev_release = vpe_device_release, |
| 320 | .dev_groups = vpe_groups, |
| 321 | }; |
| 322 | |
| 323 | static struct device vpe_device; |
| 324 | |
| 325 | int __init vpe_module_init(void) |
| 326 | { |
| 327 | unsigned int mtflags, vpflags; |
| 328 | unsigned long flags, val; |
| 329 | struct vpe *v = NULL; |
| 330 | struct tc *t; |
| 331 | int tc, err; |
| 332 | |
| 333 | if (!cpu_has_mipsmt) { |
| 334 | pr_warn("VPE loader: not a MIPS MT capable processor\n"); |
| 335 | return -ENODEV; |
| 336 | } |
| 337 | |
| 338 | if (vpelimit == 0) { |
| 339 | pr_warn("No VPEs reserved for AP/SP, not initialize VPE loader\n" |
| 340 | "Pass maxvpes=<n> argument as kernel argument\n"); |
| 341 | |
| 342 | return -ENODEV; |
| 343 | } |
| 344 | |
| 345 | if (aprp_cpu_index() == 0) { |
| 346 | pr_warn("No TCs reserved for AP/SP, not initialize VPE loader\n" |
| 347 | "Pass maxtcs=<n> argument as kernel argument\n"); |
| 348 | |
| 349 | return -ENODEV; |
| 350 | } |
| 351 | |
| 352 | major = register_chrdev(0, VPE_MODULE_NAME, &vpe_fops); |
| 353 | if (major < 0) { |
| 354 | pr_warn("VPE loader: unable to register character device\n"); |
| 355 | return major; |
| 356 | } |
| 357 | |
| 358 | err = class_register(&vpe_class); |
| 359 | if (err) { |
| 360 | pr_err("vpe_class registration failed\n"); |
| 361 | goto out_chrdev; |
| 362 | } |
| 363 | |
| 364 | device_initialize(&vpe_device); |
Zheng Yongjun | 3a845b3 | 2020-12-16 21:08:51 +0800 | [diff] [blame] | 365 | vpe_device.class = &vpe_class; |
| 366 | vpe_device.parent = NULL; |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 367 | dev_set_name(&vpe_device, "vpe1"); |
| 368 | vpe_device.devt = MKDEV(major, VPE_MODULE_MINOR); |
| 369 | err = device_add(&vpe_device); |
| 370 | if (err) { |
| 371 | pr_err("Adding vpe_device failed\n"); |
| 372 | goto out_class; |
| 373 | } |
| 374 | |
| 375 | local_irq_save(flags); |
| 376 | mtflags = dmt(); |
| 377 | vpflags = dvpe(); |
| 378 | |
| 379 | /* Put MVPE's into 'configuration state' */ |
| 380 | set_c0_mvpcontrol(MVPCONTROL_VPC); |
| 381 | |
| 382 | val = read_c0_mvpconf0(); |
| 383 | hw_tcs = (val & MVPCONF0_PTC) + 1; |
| 384 | hw_vpes = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1; |
| 385 | |
| 386 | for (tc = aprp_cpu_index(); tc < hw_tcs; tc++) { |
| 387 | /* |
| 388 | * Must re-enable multithreading temporarily or in case we |
| 389 | * reschedule send IPIs or similar we might hang. |
| 390 | */ |
| 391 | clear_c0_mvpcontrol(MVPCONTROL_VPC); |
| 392 | evpe(vpflags); |
| 393 | emt(mtflags); |
| 394 | local_irq_restore(flags); |
| 395 | t = alloc_tc(tc); |
| 396 | if (!t) { |
| 397 | err = -ENOMEM; |
| 398 | goto out_dev; |
| 399 | } |
| 400 | |
| 401 | local_irq_save(flags); |
| 402 | mtflags = dmt(); |
| 403 | vpflags = dvpe(); |
| 404 | set_c0_mvpcontrol(MVPCONTROL_VPC); |
| 405 | |
| 406 | /* VPE's */ |
| 407 | if (tc < hw_tcs) { |
| 408 | settc(tc); |
| 409 | |
| 410 | v = alloc_vpe(tc); |
| 411 | if (v == NULL) { |
| 412 | pr_warn("VPE: unable to allocate VPE\n"); |
| 413 | goto out_reenable; |
| 414 | } |
| 415 | |
| 416 | v->ntcs = hw_tcs - aprp_cpu_index(); |
| 417 | |
| 418 | /* add the tc to the list of this vpe's tc's. */ |
| 419 | list_add(&t->tc, &v->tc); |
| 420 | |
| 421 | /* deactivate all but vpe0 */ |
| 422 | if (tc >= aprp_cpu_index()) { |
| 423 | unsigned long tmp = read_vpe_c0_vpeconf0(); |
| 424 | |
| 425 | tmp &= ~VPECONF0_VPA; |
| 426 | |
| 427 | /* master VPE */ |
| 428 | tmp |= VPECONF0_MVP; |
| 429 | write_vpe_c0_vpeconf0(tmp); |
| 430 | } |
| 431 | |
| 432 | /* disable multi-threading with TC's */ |
| 433 | write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & |
| 434 | ~VPECONTROL_TE); |
| 435 | |
| 436 | if (tc >= vpelimit) { |
| 437 | /* |
| 438 | * Set config to be the same as vpe0, |
| 439 | * particularly kseg0 coherency alg |
| 440 | */ |
| 441 | write_vpe_c0_config(read_c0_config()); |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | /* TC's */ |
| 446 | t->pvpe = v; /* set the parent vpe */ |
| 447 | |
| 448 | if (tc >= aprp_cpu_index()) { |
| 449 | unsigned long tmp; |
| 450 | |
| 451 | settc(tc); |
| 452 | |
Ralf Baechle | b633648 | 2014-05-23 16:29:44 +0200 | [diff] [blame] | 453 | /* |
| 454 | * A TC that is bound to any other VPE gets bound to |
| 455 | * VPE0, ideally I'd like to make it homeless but it |
| 456 | * doesn't appear to let me bind a TC to a non-existent |
| 457 | * VPE. Which is perfectly reasonable. |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 458 | * |
| 459 | * The (un)bound state is visible to an EJTAG probe so |
| 460 | * may notify GDB... |
| 461 | */ |
| 462 | tmp = read_tc_c0_tcbind(); |
| 463 | if (tmp & TCBIND_CURVPE) { |
| 464 | /* tc is bound >vpe0 */ |
| 465 | write_tc_c0_tcbind(tmp & ~TCBIND_CURVPE); |
| 466 | |
| 467 | t->pvpe = get_vpe(0); /* set the parent vpe */ |
| 468 | } |
| 469 | |
| 470 | /* halt the TC */ |
| 471 | write_tc_c0_tchalt(TCHALT_H); |
| 472 | mips_ihb(); |
| 473 | |
| 474 | tmp = read_tc_c0_tcstatus(); |
| 475 | |
| 476 | /* mark not activated and not dynamically allocatable */ |
| 477 | tmp &= ~(TCSTATUS_A | TCSTATUS_DA); |
| 478 | tmp |= TCSTATUS_IXMT; /* interrupt exempt */ |
| 479 | write_tc_c0_tcstatus(tmp); |
| 480 | } |
| 481 | } |
| 482 | |
| 483 | out_reenable: |
| 484 | /* release config state */ |
| 485 | clear_c0_mvpcontrol(MVPCONTROL_VPC); |
| 486 | |
| 487 | evpe(vpflags); |
| 488 | emt(mtflags); |
| 489 | local_irq_restore(flags); |
| 490 | |
| 491 | return 0; |
| 492 | |
| 493 | out_dev: |
| 494 | device_del(&vpe_device); |
| 495 | |
| 496 | out_class: |
Yang Yingliang | 5822e8c | 2022-11-04 11:39:44 +0800 | [diff] [blame] | 497 | put_device(&vpe_device); |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 498 | class_unregister(&vpe_class); |
| 499 | |
| 500 | out_chrdev: |
| 501 | unregister_chrdev(major, VPE_MODULE_NAME); |
| 502 | |
| 503 | return err; |
| 504 | } |
| 505 | |
| 506 | void __exit vpe_module_exit(void) |
| 507 | { |
| 508 | struct vpe *v, *n; |
| 509 | |
Yang Yingliang | 5822e8c | 2022-11-04 11:39:44 +0800 | [diff] [blame] | 510 | device_unregister(&vpe_device); |
Deng-Cheng Zhu | 1a2a6d7 | 2013-10-30 15:52:06 -0500 | [diff] [blame] | 511 | class_unregister(&vpe_class); |
| 512 | unregister_chrdev(major, VPE_MODULE_NAME); |
| 513 | |
| 514 | /* No locking needed here */ |
| 515 | list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) { |
| 516 | if (v->state != VPE_STATE_UNUSED) |
| 517 | release_vpe(v); |
| 518 | } |
| 519 | } |