drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c

   1 /*
   2  * Copyright 2009 Jerome Glisse.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sub license, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  *
  21  * The above copyright notice and this permission notice (including the
  22  * next paragraph) shall be included in all copies or substantial portions
  23  * of the Software.
  24  *
  25  */
  26 /*
  27  * Authors:
  28  *    Jerome Glisse <glisse@freedesktop.org>
  29  *    Dave Airlie
  30  */
  31 #include <linux/seq_file.h>
  32 #include <linux/atomic.h>
  33 #include <linux/wait.h>
  34 #include <linux/kref.h>
  35 #include <linux/slab.h>
  36 #include <linux/firmware.h>
  37 #include <linux/pm_runtime.h>
  38
  39 #include <drm/drm_debugfs.h>
  40
  41 #include "amdgpu.h"
  42 #include "amdgpu_trace.h"
  43
  44 /*
  45  * Fences
  46  * Fences mark an event in the GPUs pipeline and are used
  47  * for GPU/CPU synchronization.  When the fence is written,
  48  * it is expected that all buffers associated with that fence
  49  * are no longer in use by the associated ring on the GPU and
  50  * that the the relevant GPU caches have been flushed.
  51  */
  52
  53 struct amdgpu_fence {
  54         struct dma_fence base;
  55
  56         /* RB, DMA, etc. */
  57         struct amdgpu_ring              *ring;
  58 };
  59
  60 static struct kmem_cache *amdgpu_fence_slab;
  61
  62 int amdgpu_fence_slab_init(void)
  63 {
  64         amdgpu_fence_slab = kmem_cache_create(
  65                 "amdgpu_fence", sizeof(struct amdgpu_fence), 0,
  66                 SLAB_HWCACHE_ALIGN, NULL);
  67         if (!amdgpu_fence_slab)
  68                 return -ENOMEM;
  69         return 0;
  70 }
  71
  72 void amdgpu_fence_slab_fini(void)
  73 {
  74         rcu_barrier();
  75         kmem_cache_destroy(amdgpu_fence_slab);
  76 }
  77 /*
  78  * Cast helper
  79  */
  80 static const struct dma_fence_ops amdgpu_fence_ops;
  81 static inline struct amdgpu_fence *to_amdgpu_fence(struct dma_fence *f)
  82 {
  83         struct amdgpu_fence *__f = container_of(f, struct amdgpu_fence, base);
  84
  85         if (__f->base.ops == &amdgpu_fence_ops)
  86                 return __f;
  87
  88         return NULL;
  89 }
  90
  91 /**
  92  * amdgpu_fence_write - write a fence value
  93  *
  94  * @ring: ring the fence is associated with
  95  * @seq: sequence number to write
  96  *
  97  * Writes a fence value to memory (all asics).
  98  */
  99 static void amdgpu_fence_write(struct amdgpu_ring *ring, u32 seq)
 100 {
 101         struct amdgpu_fence_driver *drv = &ring->fence_drv;
 102
 103         if (drv->cpu_addr)
 104                 *drv->cpu_addr = cpu_to_le32(seq);
 105 }
 106
 107 /**
 108  * amdgpu_fence_read - read a fence value
 109  *
 110  * @ring: ring the fence is associated with
 111  *
 112  * Reads a fence value from memory (all asics).
 113  * Returns the value of the fence read from memory.
 114  */
 115 static u32 amdgpu_fence_read(struct amdgpu_ring *ring)
 116 {
 117         struct amdgpu_fence_driver *drv = &ring->fence_drv;
 118         u32 seq = 0;
 119
 120         if (drv->cpu_addr)
 121                 seq = le32_to_cpu(*drv->cpu_addr);
 122         else
 123                 seq = atomic_read(&drv->last_seq);
 124
 125         return seq;
 126 }
 127
 128 /**
 129  * amdgpu_fence_emit - emit a fence on the requested ring
 130  *
 131  * @ring: ring the fence is associated with
 132  * @f: resulting fence object
 133  *
 134  * Emits a fence command on the requested ring (all asics).
 135  * Returns 0 on success, -ENOMEM on failure.
 136  */
 137 int amdgpu_fence_emit(struct amdgpu_ring *ring, struct dma_fence **f,
 138                       unsigned flags)
 139 {
 140         struct amdgpu_device *adev = ring->adev;
 141         struct amdgpu_fence *fence;
 142         struct dma_fence __rcu **ptr;
 143         uint32_t seq;
 144         int r;
 145
 146         fence = kmem_cache_alloc(amdgpu_fence_slab, GFP_KERNEL);
 147         if (fence == NULL)
 148                 return -ENOMEM;
 149
 150         seq = ++ring->fence_drv.sync_seq;
 151         fence->ring = ring;
 152         dma_fence_init(&fence->base, &amdgpu_fence_ops,
 153                        &ring->fence_drv.lock,
 154                        adev->fence_context + ring->idx,
 155                        seq);
 156         amdgpu_ring_emit_fence(ring, ring->fence_drv.gpu_addr,
 157                                seq, flags | AMDGPU_FENCE_FLAG_INT);
 158         pm_runtime_get_noresume(adev_to_drm(adev)->dev);
 159         ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask];
 160         if (unlikely(rcu_dereference_protected(*ptr, 1))) {
 161                 struct dma_fence *old;
 162
 163                 rcu_read_lock();
 164                 old = dma_fence_get_rcu_safe(ptr);
 165                 rcu_read_unlock();
 166
 167                 if (old) {
 168                         r = dma_fence_wait(old, false);
 169                         dma_fence_put(old);
 170                         if (r)
 171                                 return r;
 172                 }
 173         }
 174
 175         /* This function can't be called concurrently anyway, otherwise
 176          * emitting the fence would mess up the hardware ring buffer.
 177          */
 178         rcu_assign_pointer(*ptr, dma_fence_get(&fence->base));
 179
 180         *f = &fence->base;
 181
 182         return 0;
 183 }
 184
 185 /**
 186  * amdgpu_fence_emit_polling - emit a fence on the requeste ring
 187  *
 188  * @ring: ring the fence is associated with
 189  * @s: resulting sequence number
 190  *
 191  * Emits a fence command on the requested ring (all asics).
 192  * Used For polling fence.
 193  * Returns 0 on success, -ENOMEM on failure.
 194  */
 195 int amdgpu_fence_emit_polling(struct amdgpu_ring *ring, uint32_t *s,
 196                               uint32_t timeout)
 197 {
 198         uint32_t seq;
 199         signed long r;
 200
 201         if (!s)
 202                 return -EINVAL;
 203
 204         seq = ++ring->fence_drv.sync_seq;
 205         r = amdgpu_fence_wait_polling(ring,
 206                                       seq - ring->fence_drv.num_fences_mask,
 207                                       timeout);
 208         if (r < 1)
 209                 return -ETIMEDOUT;
 210
 211         amdgpu_ring_emit_fence(ring, ring->fence_drv.gpu_addr,
 212                                seq, 0);
 213
 214         *s = seq;
 215
 216         return 0;
 217 }
 218
 219 /**
 220  * amdgpu_fence_schedule_fallback - schedule fallback check
 221  *
 222  * @ring: pointer to struct amdgpu_ring
 223  *
 224  * Start a timer as fallback to our interrupts.
 225  */
 226 static void amdgpu_fence_schedule_fallback(struct amdgpu_ring *ring)
 227 {
 228         mod_timer(&ring->fence_drv.fallback_timer,
 229                   jiffies + AMDGPU_FENCE_JIFFIES_TIMEOUT);
 230 }
 231
 232 /**
 233  * amdgpu_fence_process - check for fence activity
 234  *
 235  * @ring: pointer to struct amdgpu_ring
 236  *
 237  * Checks the current fence value and calculates the last
 238  * signalled fence value. Wakes the fence queue if the
 239  * sequence number has increased.
 240  *
 241  * Returns true if fence was processed
 242  */
 243 bool amdgpu_fence_process(struct amdgpu_ring *ring)
 244 {
 245         struct amdgpu_fence_driver *drv = &ring->fence_drv;
 246         struct amdgpu_device *adev = ring->adev;
 247         uint32_t seq, last_seq;
 248         int r;
 249
 250         do {
 251                 last_seq = atomic_read(&ring->fence_drv.last_seq);
 252                 seq = amdgpu_fence_read(ring);
 253
 254         } while (atomic_cmpxchg(&drv->last_seq, last_seq, seq) != last_seq);
 255
 256         if (del_timer(&ring->fence_drv.fallback_timer) &&
 257             seq != ring->fence_drv.sync_seq)
 258                 amdgpu_fence_schedule_fallback(ring);
 259
 260         if (unlikely(seq == last_seq))
 261                 return false;
 262
 263         last_seq &= drv->num_fences_mask;
 264         seq &= drv->num_fences_mask;
 265
 266         do {
 267                 struct dma_fence *fence, **ptr;
 268
 269                 ++last_seq;
 270                 last_seq &= drv->num_fences_mask;
 271                 ptr = &drv->fences[last_seq];
 272
 273                 /* There is always exactly one thread signaling this fence slot */
 274                 fence = rcu_dereference_protected(*ptr, 1);
 275                 RCU_INIT_POINTER(*ptr, NULL);
 276
 277                 if (!fence)
 278                         continue;
 279
 280                 r = dma_fence_signal(fence);
 281                 if (!r)
 282                         DMA_FENCE_TRACE(fence, "signaled from irq context\n");
 283                 else
 284                         BUG();
 285
 286                 dma_fence_put(fence);
 287                 pm_runtime_mark_last_busy(adev_to_drm(adev)->dev);
 288                 pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
 289         } while (last_seq != seq);
 290
 291         return true;
 292 }
 293
 294 /**
 295  * amdgpu_fence_fallback - fallback for hardware interrupts
 296  *
 297  * @work: delayed work item
 298  *
 299  * Checks for fence activity.
 300  */
 301 static void amdgpu_fence_fallback(struct timer_list *t)
 302 {
 303         struct amdgpu_ring *ring = from_timer(ring, t,
 304                                               fence_drv.fallback_timer);
 305
 306         if (amdgpu_fence_process(ring))
 307                 DRM_WARN("Fence fallback timer expired on ring %s\n", ring->name);
 308 }
 309
 310 /**
 311  * amdgpu_fence_wait_empty - wait for all fences to signal
 312  *
 313  * @adev: amdgpu device pointer
 314  * @ring: ring index the fence is associated with
 315  *
 316  * Wait for all fences on the requested ring to signal (all asics).
 317  * Returns 0 if the fences have passed, error for all other cases.
 318  */
 319 int amdgpu_fence_wait_empty(struct amdgpu_ring *ring)
 320 {
 321         uint64_t seq = READ_ONCE(ring->fence_drv.sync_seq);
 322         struct dma_fence *fence, **ptr;
 323         int r;
 324
 325         if (!seq)
 326                 return 0;
 327
 328         ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask];
 329         rcu_read_lock();
 330         fence = rcu_dereference(*ptr);
 331         if (!fence || !dma_fence_get_rcu(fence)) {
 332                 rcu_read_unlock();
 333                 return 0;
 334         }
 335         rcu_read_unlock();
 336
 337         r = dma_fence_wait(fence, false);
 338         dma_fence_put(fence);
 339         return r;
 340 }
 341
 342 /**
 343  * amdgpu_fence_wait_polling - busy wait for givn sequence number
 344  *
 345  * @ring: ring index the fence is associated with
 346  * @wait_seq: sequence number to wait
 347  * @timeout: the timeout for waiting in usecs
 348  *
 349  * Wait for all fences on the requested ring to signal (all asics).
 350  * Returns left time if no timeout, 0 or minus if timeout.
 351  */
 352 signed long amdgpu_fence_wait_polling(struct amdgpu_ring *ring,
 353                                       uint32_t wait_seq,
 354                                       signed long timeout)
 355 {
 356         uint32_t seq;
 357
 358         do {
 359                 seq = amdgpu_fence_read(ring);
 360                 udelay(5);
 361                 timeout -= 5;
 362         } while ((int32_t)(wait_seq - seq) > 0 && timeout > 0);
 363
 364         return timeout > 0 ? timeout : 0;
 365 }
 366 /**
 367  * amdgpu_fence_count_emitted - get the count of emitted fences
 368  *
 369  * @ring: ring the fence is associated with
 370  *
 371  * Get the number of fences emitted on the requested ring (all asics).
 372  * Returns the number of emitted fences on the ring.  Used by the
 373  * dynpm code to ring track activity.
 374  */
 375 unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring)
 376 {
 377         uint64_t emitted;
 378
 379         /* We are not protected by ring lock when reading the last sequence
 380          * but it's ok to report slightly wrong fence count here.
 381          */
 382         amdgpu_fence_process(ring);
 383         emitted = 0x100000000ull;
 384         emitted -= atomic_read(&ring->fence_drv.last_seq);
 385         emitted += READ_ONCE(ring->fence_drv.sync_seq);
 386         return lower_32_bits(emitted);
 387 }
 388
 389 /**
 390  * amdgpu_fence_driver_start_ring - make the fence driver
 391  * ready for use on the requested ring.
 392  *
 393  * @ring: ring to start the fence driver on
 394  * @irq_src: interrupt source to use for this ring
 395  * @irq_type: interrupt type to use for this ring
 396  *
 397  * Make the fence driver ready for processing (all asics).
 398  * Not all asics have all rings, so each asic will only
 399  * start the fence driver on the rings it has.
 400  * Returns 0 for success, errors for failure.
 401  */
 402 int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
 403                                    struct amdgpu_irq_src *irq_src,
 404                                    unsigned irq_type)
 405 {
 406         struct amdgpu_device *adev = ring->adev;
 407         uint64_t index;
 408
 409         if (ring->funcs->type != AMDGPU_RING_TYPE_UVD) {
 410                 ring->fence_drv.cpu_addr = &adev->wb.wb[ring->fence_offs];
 411                 ring->fence_drv.gpu_addr = adev->wb.gpu_addr + (ring->fence_offs * 4);
 412         } else {
 413                 /* put fence directly behind firmware */
 414                 index = ALIGN(adev->uvd.fw->size, 8);
 415                 ring->fence_drv.cpu_addr = adev->uvd.inst[ring->me].cpu_addr + index;
 416                 ring->fence_drv.gpu_addr = adev->uvd.inst[ring->me].gpu_addr + index;
 417         }
 418         amdgpu_fence_write(ring, atomic_read(&ring->fence_drv.last_seq));
 419
 420         if (irq_src)
 421                 amdgpu_irq_get(adev, irq_src, irq_type);
 422
 423         ring->fence_drv.irq_src = irq_src;
 424         ring->fence_drv.irq_type = irq_type;
 425         ring->fence_drv.initialized = true;
 426
 427         DRM_DEV_DEBUG(adev->dev, "fence driver on ring %s use gpu addr 0x%016llx\n",
 428                       ring->name, ring->fence_drv.gpu_addr);
 429         return 0;
 430 }
 431
 432 /**
 433  * amdgpu_fence_driver_init_ring - init the fence driver
 434  * for the requested ring.
 435  *
 436  * @ring: ring to init the fence driver on
 437  * @num_hw_submission: number of entries on the hardware queue
 438  *
 439  * Init the fence driver for the requested ring (all asics).
 440  * Helper function for amdgpu_fence_driver_init().
 441  */
 442 int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring,
 443                                   unsigned num_hw_submission)
 444 {
 445         struct amdgpu_device *adev = ring->adev;
 446         long timeout;
 447         int r;
 448
 449         if (!adev)
 450                 return -EINVAL;
 451
 452         if (!is_power_of_2(num_hw_submission))
 453                 return -EINVAL;
 454
 455         ring->fence_drv.cpu_addr = NULL;
 456         ring->fence_drv.gpu_addr = 0;
 457         ring->fence_drv.sync_seq = 0;
 458         atomic_set(&ring->fence_drv.last_seq, 0);
 459         ring->fence_drv.initialized = false;
 460
 461         timer_setup(&ring->fence_drv.fallback_timer, amdgpu_fence_fallback, 0);
 462
 463         ring->fence_drv.num_fences_mask = num_hw_submission * 2 - 1;
 464         spin_lock_init(&ring->fence_drv.lock);
 465         ring->fence_drv.fences = kcalloc(num_hw_submission * 2, sizeof(void *),
 466                                          GFP_KERNEL);
 467         if (!ring->fence_drv.fences)
 468                 return -ENOMEM;
 469
 470         /* No need to setup the GPU scheduler for rings that don't need it */
 471         if (!ring->no_scheduler) {
 472                 switch (ring->funcs->type) {
 473                 case AMDGPU_RING_TYPE_GFX:
 474                         timeout = adev->gfx_timeout;
 475                         break;
 476                 case AMDGPU_RING_TYPE_COMPUTE:
 477                         timeout = adev->compute_timeout;
 478                         break;
 479                 case AMDGPU_RING_TYPE_SDMA:
 480                         timeout = adev->sdma_timeout;
 481                         break;
 482                 default:
 483                         timeout = adev->video_timeout;
 484                         break;
 485                 }
 486
 487                 r = drm_sched_init(&ring->sched, &amdgpu_sched_ops,
 488                                    num_hw_submission, amdgpu_job_hang_limit,
 489                                    timeout, ring->name);
 490                 if (r) {
 491                         DRM_ERROR("Failed to create scheduler on ring %s.\n",
 492                                   ring->name);
 493                         return r;
 494                 }
 495         }
 496
 497         return 0;
 498 }
 499
 500 /**
 501  * amdgpu_fence_driver_init - init the fence driver
 502  * for all possible rings.
 503  *
 504  * @adev: amdgpu device pointer
 505  *
 506  * Init the fence driver for all possible rings (all asics).
 507  * Not all asics have all rings, so each asic will only
 508  * start the fence driver on the rings it has using
 509  * amdgpu_fence_driver_start_ring().
 510  * Returns 0 for success.
 511  */
 512 int amdgpu_fence_driver_init(struct amdgpu_device *adev)
 513 {
 514         return 0;
 515 }
 516
 517 /**
 518  * amdgpu_fence_driver_fini - tear down the fence driver
 519  * for all possible rings.
 520  *
 521  * @adev: amdgpu device pointer
 522  *
 523  * Tear down the fence driver for all possible rings (all asics).
 524  */
 525 void amdgpu_fence_driver_fini(struct amdgpu_device *adev)
 526 {
 527         unsigned i, j;
 528         int r;
 529
 530         for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
 531                 struct amdgpu_ring *ring = adev->rings[i];
 532
 533                 if (!ring || !ring->fence_drv.initialized)
 534                         continue;
 535                 r = amdgpu_fence_wait_empty(ring);
 536                 if (r) {
 537                         /* no need to trigger GPU reset as we are unloading */
 538                         amdgpu_fence_driver_force_completion(ring);
 539                 }
 540                 if (ring->fence_drv.irq_src)
 541                         amdgpu_irq_put(adev, ring->fence_drv.irq_src,
 542                                        ring->fence_drv.irq_type);
 543                 if (!ring->no_scheduler)
 544                         drm_sched_fini(&ring->sched);
 545                 del_timer_sync(&ring->fence_drv.fallback_timer);
 546                 for (j = 0; j <= ring->fence_drv.num_fences_mask; ++j)
 547                         dma_fence_put(ring->fence_drv.fences[j]);
 548                 kfree(ring->fence_drv.fences);
 549                 ring->fence_drv.fences = NULL;
 550                 ring->fence_drv.initialized = false;
 551         }
 552 }
 553
 554 /**
 555  * amdgpu_fence_driver_suspend - suspend the fence driver
 556  * for all possible rings.
 557  *
 558  * @adev: amdgpu device pointer
 559  *
 560  * Suspend the fence driver for all possible rings (all asics).
 561  */
 562 void amdgpu_fence_driver_suspend(struct amdgpu_device *adev)
 563 {
 564         int i, r;
 565
 566         for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
 567                 struct amdgpu_ring *ring = adev->rings[i];
 568                 if (!ring || !ring->fence_drv.initialized)
 569                         continue;
 570
 571                 /* wait for gpu to finish processing current batch */
 572                 r = amdgpu_fence_wait_empty(ring);
 573                 if (r) {
 574                         /* delay GPU reset to resume */
 575                         amdgpu_fence_driver_force_completion(ring);
 576                 }
 577
 578                 /* disable the interrupt */
 579                 if (ring->fence_drv.irq_src)
 580                         amdgpu_irq_put(adev, ring->fence_drv.irq_src,
 581                                        ring->fence_drv.irq_type);
 582         }
 583 }
 584
 585 /**
 586  * amdgpu_fence_driver_resume - resume the fence driver
 587  * for all possible rings.
 588  *
 589  * @adev: amdgpu device pointer
 590  *
 591  * Resume the fence driver for all possible rings (all asics).
 592  * Not all asics have all rings, so each asic will only
 593  * start the fence driver on the rings it has using
 594  * amdgpu_fence_driver_start_ring().
 595  * Returns 0 for success.
 596  */
 597 void amdgpu_fence_driver_resume(struct amdgpu_device *adev)
 598 {
 599         int i;
 600
 601         for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
 602                 struct amdgpu_ring *ring = adev->rings[i];
 603                 if (!ring || !ring->fence_drv.initialized)
 604                         continue;
 605
 606                 /* enable the interrupt */
 607                 if (ring->fence_drv.irq_src)
 608                         amdgpu_irq_get(adev, ring->fence_drv.irq_src,
 609                                        ring->fence_drv.irq_type);
 610         }
 611 }
 612
 613 /**
 614  * amdgpu_fence_driver_force_completion - force signal latest fence of ring
 615  *
 616  * @ring: fence of the ring to signal
 617  *
 618  */
 619 void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring)
 620 {
 621         amdgpu_fence_write(ring, ring->fence_drv.sync_seq);
 622         amdgpu_fence_process(ring);
 623 }
 624
 625 /*
 626  * Common fence implementation
 627  */
 628
 629 static const char *amdgpu_fence_get_driver_name(struct dma_fence *fence)
 630 {
 631         return "amdgpu";
 632 }
 633
 634 static const char *amdgpu_fence_get_timeline_name(struct dma_fence *f)
 635 {
 636         struct amdgpu_fence *fence = to_amdgpu_fence(f);
 637         return (const char *)fence->ring->name;
 638 }
 639
 640 /**
 641  * amdgpu_fence_enable_signaling - enable signalling on fence
 642  * @fence: fence
 643  *
 644  * This function is called with fence_queue lock held, and adds a callback
 645  * to fence_queue that checks if this fence is signaled, and if so it
 646  * signals the fence and removes itself.
 647  */
 648 static bool amdgpu_fence_enable_signaling(struct dma_fence *f)
 649 {
 650         struct amdgpu_fence *fence = to_amdgpu_fence(f);
 651         struct amdgpu_ring *ring = fence->ring;
 652
 653         if (!timer_pending(&ring->fence_drv.fallback_timer))
 654                 amdgpu_fence_schedule_fallback(ring);
 655
 656         DMA_FENCE_TRACE(&fence->base, "armed on ring %i!\n", ring->idx);
 657
 658         return true;
 659 }
 660
 661 /**
 662  * amdgpu_fence_free - free up the fence memory
 663  *
 664  * @rcu: RCU callback head
 665  *
 666  * Free up the fence memory after the RCU grace period.
 667  */
 668 static void amdgpu_fence_free(struct rcu_head *rcu)
 669 {
 670         struct dma_fence *f = container_of(rcu, struct dma_fence, rcu);
 671         struct amdgpu_fence *fence = to_amdgpu_fence(f);
 672         kmem_cache_free(amdgpu_fence_slab, fence);
 673 }
 674
 675 /**
 676  * amdgpu_fence_release - callback that fence can be freed
 677  *
 678  * @fence: fence
 679  *
 680  * This function is called when the reference count becomes zero.
 681  * It just RCU schedules freeing up the fence.
 682  */
 683 static void amdgpu_fence_release(struct dma_fence *f)
 684 {
 685         call_rcu(&f->rcu, amdgpu_fence_free);
 686 }
 687
 688 static const struct dma_fence_ops amdgpu_fence_ops = {
 689         .get_driver_name = amdgpu_fence_get_driver_name,
 690         .get_timeline_name = amdgpu_fence_get_timeline_name,
 691         .enable_signaling = amdgpu_fence_enable_signaling,
 692         .release = amdgpu_fence_release,
 693 };
 694
 695 /*
 696  * Fence debugfs
 697  */
 698 #if defined(CONFIG_DEBUG_FS)
 699 static int amdgpu_debugfs_fence_info(struct seq_file *m, void *data)
 700 {
 701         struct drm_info_node *node = (struct drm_info_node *)m->private;
 702         struct drm_device *dev = node->minor->dev;
 703         struct amdgpu_device *adev = drm_to_adev(dev);
 704         int i;
 705
 706         for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 707                 struct amdgpu_ring *ring = adev->rings[i];
 708                 if (!ring || !ring->fence_drv.initialized)
 709                         continue;
 710
 711                 amdgpu_fence_process(ring);
 712
 713                 seq_printf(m, "--- ring %d (%s) ---\n", i, ring->name);
 714                 seq_printf(m, "Last signaled fence          0x%08x\n",
 715                            atomic_read(&ring->fence_drv.last_seq));
 716                 seq_printf(m, "Last emitted                 0x%08x\n",
 717                            ring->fence_drv.sync_seq);
 718
 719                 if (ring->funcs->type == AMDGPU_RING_TYPE_GFX ||
 720                     ring->funcs->type == AMDGPU_RING_TYPE_SDMA) {
 721                         seq_printf(m, "Last signaled trailing fence 0x%08x\n",
 722                                    le32_to_cpu(*ring->trail_fence_cpu_addr));
 723                         seq_printf(m, "Last emitted                 0x%08x\n",
 724                                    ring->trail_seq);
 725                 }
 726
 727                 if (ring->funcs->type != AMDGPU_RING_TYPE_GFX)
 728                         continue;
 729
 730                 /* set in CP_VMID_PREEMPT and preemption occurred */
 731                 seq_printf(m, "Last preempted               0x%08x\n",
 732                            le32_to_cpu(*(ring->fence_drv.cpu_addr + 2)));
 733                 /* set in CP_VMID_RESET and reset occurred */
 734                 seq_printf(m, "Last reset                   0x%08x\n",
 735                            le32_to_cpu(*(ring->fence_drv.cpu_addr + 4)));
 736                 /* Both preemption and reset occurred */
 737                 seq_printf(m, "Last both                    0x%08x\n",
 738                            le32_to_cpu(*(ring->fence_drv.cpu_addr + 6)));
 739         }
 740         return 0;
 741 }
 742
 743 /**
 744  * amdgpu_debugfs_gpu_recover - manually trigger a gpu reset & recover
 745  *
 746  * Manually trigger a gpu reset at the next fence wait.
 747  */
 748 static int amdgpu_debugfs_gpu_recover(struct seq_file *m, void *data)
 749 {
 750         struct drm_info_node *node = (struct drm_info_node *) m->private;
 751         struct drm_device *dev = node->minor->dev;
 752         struct amdgpu_device *adev = drm_to_adev(dev);
 753         int r;
 754
 755         r = pm_runtime_get_sync(dev->dev);
 756         if (r < 0) {
 757                 pm_runtime_put_autosuspend(dev->dev);
 758                 return 0;
 759         }
 760
 761         seq_printf(m, "gpu recover\n");
 762         amdgpu_device_gpu_recover(adev, NULL);
 763
 764         pm_runtime_mark_last_busy(dev->dev);
 765         pm_runtime_put_autosuspend(dev->dev);
 766
 767         return 0;
 768 }
 769
 770 static const struct drm_info_list amdgpu_debugfs_fence_list[] = {
 771         {"amdgpu_fence_info", &amdgpu_debugfs_fence_info, 0, NULL},
 772         {"amdgpu_gpu_recover", &amdgpu_debugfs_gpu_recover, 0, NULL}
 773 };
 774
 775 static const struct drm_info_list amdgpu_debugfs_fence_list_sriov[] = {
 776         {"amdgpu_fence_info", &amdgpu_debugfs_fence_info, 0, NULL},
 777 };
 778 #endif
 779
 780 int amdgpu_debugfs_fence_init(struct amdgpu_device *adev)
 781 {
 782 #if defined(CONFIG_DEBUG_FS)
 783         if (amdgpu_sriov_vf(adev))
 784                 return amdgpu_debugfs_add_files(adev, amdgpu_debugfs_fence_list_sriov,
 785                                                 ARRAY_SIZE(amdgpu_debugfs_fence_list_sriov));
 786         return amdgpu_debugfs_add_files(adev, amdgpu_debugfs_fence_list,
 787                                         ARRAY_SIZE(amdgpu_debugfs_fence_list));
 788 #else
 789         return 0;
 790 #endif
 791 }
 792