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 <drm/drmP.h> 38 #include "amdgpu.h" 39 #include "amdgpu_trace.h" 40 41 /* 42 * Fences 43 * Fences mark an event in the GPUs pipeline and are used 44 * for GPU/CPU synchronization. When the fence is written, 45 * it is expected that all buffers associated with that fence 46 * are no longer in use by the associated ring on the GPU and 47 * that the the relevant GPU caches have been flushed. 48 */ 49 50 struct amdgpu_fence { 51 struct dma_fence base; 52 53 /* RB, DMA, etc. */ 54 struct amdgpu_ring *ring; 55 }; 56 57 static struct kmem_cache *amdgpu_fence_slab; 58 59 int amdgpu_fence_slab_init(void) 60 { 61 amdgpu_fence_slab = kmem_cache_create( 62 "amdgpu_fence", sizeof(struct amdgpu_fence), 0, 63 SLAB_HWCACHE_ALIGN, NULL); 64 if (!amdgpu_fence_slab) 65 return -ENOMEM; 66 return 0; 67 } 68 69 void amdgpu_fence_slab_fini(void) 70 { 71 rcu_barrier(); 72 kmem_cache_destroy(amdgpu_fence_slab); 73 } 74 /* 75 * Cast helper 76 */ 77 static const struct dma_fence_ops amdgpu_fence_ops; 78 static inline struct amdgpu_fence *to_amdgpu_fence(struct dma_fence *f) 79 { 80 struct amdgpu_fence *__f = container_of(f, struct amdgpu_fence, base); 81 82 if (__f->base.ops == &amdgpu_fence_ops) 83 return __f; 84 85 return NULL; 86 } 87 88 /** 89 * amdgpu_fence_write - write a fence value 90 * 91 * @ring: ring the fence is associated with 92 * @seq: sequence number to write 93 * 94 * Writes a fence value to memory (all asics). 95 */ 96 static void amdgpu_fence_write(struct amdgpu_ring *ring, u32 seq) 97 { 98 struct amdgpu_fence_driver *drv = &ring->fence_drv; 99 100 if (drv->cpu_addr) 101 *drv->cpu_addr = cpu_to_le32(seq); 102 } 103 104 /** 105 * amdgpu_fence_read - read a fence value 106 * 107 * @ring: ring the fence is associated with 108 * 109 * Reads a fence value from memory (all asics). 110 * Returns the value of the fence read from memory. 111 */ 112 static u32 amdgpu_fence_read(struct amdgpu_ring *ring) 113 { 114 struct amdgpu_fence_driver *drv = &ring->fence_drv; 115 u32 seq = 0; 116 117 if (drv->cpu_addr) 118 seq = le32_to_cpu(*drv->cpu_addr); 119 else 120 seq = atomic_read(&drv->last_seq); 121 122 return seq; 123 } 124 125 /** 126 * amdgpu_fence_emit - emit a fence on the requested ring 127 * 128 * @ring: ring the fence is associated with 129 * @f: resulting fence object 130 * 131 * Emits a fence command on the requested ring (all asics). 132 * Returns 0 on success, -ENOMEM on failure. 133 */ 134 int amdgpu_fence_emit(struct amdgpu_ring *ring, struct dma_fence **f) 135 { 136 struct amdgpu_device *adev = ring->adev; 137 struct amdgpu_fence *fence; 138 struct dma_fence *old, **ptr; 139 uint32_t seq; 140 141 fence = kmem_cache_alloc(amdgpu_fence_slab, GFP_KERNEL); 142 if (fence == NULL) 143 return -ENOMEM; 144 145 seq = ++ring->fence_drv.sync_seq; 146 fence->ring = ring; 147 dma_fence_init(&fence->base, &amdgpu_fence_ops, 148 &ring->fence_drv.lock, 149 adev->fence_context + ring->idx, 150 seq); 151 amdgpu_ring_emit_fence(ring, ring->fence_drv.gpu_addr, 152 seq, AMDGPU_FENCE_FLAG_INT); 153 154 ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask]; 155 /* This function can't be called concurrently anyway, otherwise 156 * emitting the fence would mess up the hardware ring buffer. 157 */ 158 old = rcu_dereference_protected(*ptr, 1); 159 if (old && !dma_fence_is_signaled(old)) { 160 DRM_INFO("rcu slot is busy\n"); 161 dma_fence_wait(old, false); 162 } 163 164 rcu_assign_pointer(*ptr, dma_fence_get(&fence->base)); 165 166 *f = &fence->base; 167 168 return 0; 169 } 170 171 /** 172 * amdgpu_fence_schedule_fallback - schedule fallback check 173 * 174 * @ring: pointer to struct amdgpu_ring 175 * 176 * Start a timer as fallback to our interrupts. 177 */ 178 static void amdgpu_fence_schedule_fallback(struct amdgpu_ring *ring) 179 { 180 mod_timer(&ring->fence_drv.fallback_timer, 181 jiffies + AMDGPU_FENCE_JIFFIES_TIMEOUT); 182 } 183 184 /** 185 * amdgpu_fence_process - check for fence activity 186 * 187 * @ring: pointer to struct amdgpu_ring 188 * 189 * Checks the current fence value and calculates the last 190 * signalled fence value. Wakes the fence queue if the 191 * sequence number has increased. 192 */ 193 void amdgpu_fence_process(struct amdgpu_ring *ring) 194 { 195 struct amdgpu_fence_driver *drv = &ring->fence_drv; 196 uint32_t seq, last_seq; 197 int r; 198 199 do { 200 last_seq = atomic_read(&ring->fence_drv.last_seq); 201 seq = amdgpu_fence_read(ring); 202 203 } while (atomic_cmpxchg(&drv->last_seq, last_seq, seq) != last_seq); 204 205 if (seq != ring->fence_drv.sync_seq) 206 amdgpu_fence_schedule_fallback(ring); 207 208 if (unlikely(seq == last_seq)) 209 return; 210 211 last_seq &= drv->num_fences_mask; 212 seq &= drv->num_fences_mask; 213 214 do { 215 struct dma_fence *fence, **ptr; 216 217 ++last_seq; 218 last_seq &= drv->num_fences_mask; 219 ptr = &drv->fences[last_seq]; 220 221 /* There is always exactly one thread signaling this fence slot */ 222 fence = rcu_dereference_protected(*ptr, 1); 223 RCU_INIT_POINTER(*ptr, NULL); 224 225 if (!fence) 226 continue; 227 228 r = dma_fence_signal(fence); 229 if (!r) 230 DMA_FENCE_TRACE(fence, "signaled from irq context\n"); 231 else 232 BUG(); 233 234 dma_fence_put(fence); 235 } while (last_seq != seq); 236 } 237 238 /** 239 * amdgpu_fence_fallback - fallback for hardware interrupts 240 * 241 * @work: delayed work item 242 * 243 * Checks for fence activity. 244 */ 245 static void amdgpu_fence_fallback(unsigned long arg) 246 { 247 struct amdgpu_ring *ring = (void *)arg; 248 249 amdgpu_fence_process(ring); 250 } 251 252 /** 253 * amdgpu_fence_wait_empty - wait for all fences to signal 254 * 255 * @adev: amdgpu device pointer 256 * @ring: ring index the fence is associated with 257 * 258 * Wait for all fences on the requested ring to signal (all asics). 259 * Returns 0 if the fences have passed, error for all other cases. 260 */ 261 int amdgpu_fence_wait_empty(struct amdgpu_ring *ring) 262 { 263 uint64_t seq = ACCESS_ONCE(ring->fence_drv.sync_seq); 264 struct dma_fence *fence, **ptr; 265 int r; 266 267 if (!seq) 268 return 0; 269 270 ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask]; 271 rcu_read_lock(); 272 fence = rcu_dereference(*ptr); 273 if (!fence || !dma_fence_get_rcu(fence)) { 274 rcu_read_unlock(); 275 return 0; 276 } 277 rcu_read_unlock(); 278 279 r = dma_fence_wait(fence, false); 280 dma_fence_put(fence); 281 return r; 282 } 283 284 /** 285 * amdgpu_fence_count_emitted - get the count of emitted fences 286 * 287 * @ring: ring the fence is associated with 288 * 289 * Get the number of fences emitted on the requested ring (all asics). 290 * Returns the number of emitted fences on the ring. Used by the 291 * dynpm code to ring track activity. 292 */ 293 unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring) 294 { 295 uint64_t emitted; 296 297 /* We are not protected by ring lock when reading the last sequence 298 * but it's ok to report slightly wrong fence count here. 299 */ 300 amdgpu_fence_process(ring); 301 emitted = 0x100000000ull; 302 emitted -= atomic_read(&ring->fence_drv.last_seq); 303 emitted += ACCESS_ONCE(ring->fence_drv.sync_seq); 304 return lower_32_bits(emitted); 305 } 306 307 /** 308 * amdgpu_fence_driver_start_ring - make the fence driver 309 * ready for use on the requested ring. 310 * 311 * @ring: ring to start the fence driver on 312 * @irq_src: interrupt source to use for this ring 313 * @irq_type: interrupt type to use for this ring 314 * 315 * Make the fence driver ready for processing (all asics). 316 * Not all asics have all rings, so each asic will only 317 * start the fence driver on the rings it has. 318 * Returns 0 for success, errors for failure. 319 */ 320 int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring, 321 struct amdgpu_irq_src *irq_src, 322 unsigned irq_type) 323 { 324 struct amdgpu_device *adev = ring->adev; 325 uint64_t index; 326 327 if (ring != &adev->uvd.ring) { 328 ring->fence_drv.cpu_addr = &adev->wb.wb[ring->fence_offs]; 329 ring->fence_drv.gpu_addr = adev->wb.gpu_addr + (ring->fence_offs * 4); 330 } else { 331 /* put fence directly behind firmware */ 332 index = ALIGN(adev->uvd.fw->size, 8); 333 ring->fence_drv.cpu_addr = adev->uvd.cpu_addr + index; 334 ring->fence_drv.gpu_addr = adev->uvd.gpu_addr + index; 335 } 336 amdgpu_fence_write(ring, atomic_read(&ring->fence_drv.last_seq)); 337 amdgpu_irq_get(adev, irq_src, irq_type); 338 339 ring->fence_drv.irq_src = irq_src; 340 ring->fence_drv.irq_type = irq_type; 341 ring->fence_drv.initialized = true; 342 343 dev_info(adev->dev, "fence driver on ring %d use gpu addr 0x%016llx, " 344 "cpu addr 0x%p\n", ring->idx, 345 ring->fence_drv.gpu_addr, ring->fence_drv.cpu_addr); 346 return 0; 347 } 348 349 /** 350 * amdgpu_fence_driver_init_ring - init the fence driver 351 * for the requested ring. 352 * 353 * @ring: ring to init the fence driver on 354 * @num_hw_submission: number of entries on the hardware queue 355 * 356 * Init the fence driver for the requested ring (all asics). 357 * Helper function for amdgpu_fence_driver_init(). 358 */ 359 int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring, 360 unsigned num_hw_submission) 361 { 362 long timeout; 363 int r; 364 365 /* Check that num_hw_submission is a power of two */ 366 if ((num_hw_submission & (num_hw_submission - 1)) != 0) 367 return -EINVAL; 368 369 ring->fence_drv.cpu_addr = NULL; 370 ring->fence_drv.gpu_addr = 0; 371 ring->fence_drv.sync_seq = 0; 372 atomic_set(&ring->fence_drv.last_seq, 0); 373 ring->fence_drv.initialized = false; 374 375 setup_timer(&ring->fence_drv.fallback_timer, amdgpu_fence_fallback, 376 (unsigned long)ring); 377 378 ring->fence_drv.num_fences_mask = num_hw_submission * 2 - 1; 379 spin_lock_init(&ring->fence_drv.lock); 380 ring->fence_drv.fences = kcalloc(num_hw_submission * 2, sizeof(void *), 381 GFP_KERNEL); 382 if (!ring->fence_drv.fences) 383 return -ENOMEM; 384 385 /* No need to setup the GPU scheduler for KIQ ring */ 386 if (ring->funcs->type != AMDGPU_RING_TYPE_KIQ) { 387 timeout = msecs_to_jiffies(amdgpu_lockup_timeout); 388 if (timeout == 0) { 389 /* 390 * FIXME: 391 * Delayed workqueue cannot use it directly, 392 * so the scheduler will not use delayed workqueue if 393 * MAX_SCHEDULE_TIMEOUT is set. 394 * Currently keep it simple and silly. 395 */ 396 timeout = MAX_SCHEDULE_TIMEOUT; 397 } 398 r = amd_sched_init(&ring->sched, &amdgpu_sched_ops, 399 num_hw_submission, 400 timeout, ring->name); 401 if (r) { 402 DRM_ERROR("Failed to create scheduler on ring %s.\n", 403 ring->name); 404 return r; 405 } 406 } 407 408 return 0; 409 } 410 411 /** 412 * amdgpu_fence_driver_init - init the fence driver 413 * for all possible rings. 414 * 415 * @adev: amdgpu device pointer 416 * 417 * Init the fence driver for all possible rings (all asics). 418 * Not all asics have all rings, so each asic will only 419 * start the fence driver on the rings it has using 420 * amdgpu_fence_driver_start_ring(). 421 * Returns 0 for success. 422 */ 423 int amdgpu_fence_driver_init(struct amdgpu_device *adev) 424 { 425 if (amdgpu_debugfs_fence_init(adev)) 426 dev_err(adev->dev, "fence debugfs file creation failed\n"); 427 428 return 0; 429 } 430 431 /** 432 * amdgpu_fence_driver_fini - tear down the fence driver 433 * for all possible rings. 434 * 435 * @adev: amdgpu device pointer 436 * 437 * Tear down the fence driver for all possible rings (all asics). 438 */ 439 void amdgpu_fence_driver_fini(struct amdgpu_device *adev) 440 { 441 unsigned i, j; 442 int r; 443 444 for (i = 0; i < AMDGPU_MAX_RINGS; i++) { 445 struct amdgpu_ring *ring = adev->rings[i]; 446 447 if (!ring || !ring->fence_drv.initialized) 448 continue; 449 r = amdgpu_fence_wait_empty(ring); 450 if (r) { 451 /* no need to trigger GPU reset as we are unloading */ 452 amdgpu_fence_driver_force_completion(adev); 453 } 454 amdgpu_irq_put(adev, ring->fence_drv.irq_src, 455 ring->fence_drv.irq_type); 456 amd_sched_fini(&ring->sched); 457 del_timer_sync(&ring->fence_drv.fallback_timer); 458 for (j = 0; j <= ring->fence_drv.num_fences_mask; ++j) 459 dma_fence_put(ring->fence_drv.fences[j]); 460 kfree(ring->fence_drv.fences); 461 ring->fence_drv.fences = NULL; 462 ring->fence_drv.initialized = false; 463 } 464 } 465 466 /** 467 * amdgpu_fence_driver_suspend - suspend the fence driver 468 * for all possible rings. 469 * 470 * @adev: amdgpu device pointer 471 * 472 * Suspend the fence driver for all possible rings (all asics). 473 */ 474 void amdgpu_fence_driver_suspend(struct amdgpu_device *adev) 475 { 476 int i, r; 477 478 for (i = 0; i < AMDGPU_MAX_RINGS; i++) { 479 struct amdgpu_ring *ring = adev->rings[i]; 480 if (!ring || !ring->fence_drv.initialized) 481 continue; 482 483 /* wait for gpu to finish processing current batch */ 484 r = amdgpu_fence_wait_empty(ring); 485 if (r) { 486 /* delay GPU reset to resume */ 487 amdgpu_fence_driver_force_completion(adev); 488 } 489 490 /* disable the interrupt */ 491 amdgpu_irq_put(adev, ring->fence_drv.irq_src, 492 ring->fence_drv.irq_type); 493 } 494 } 495 496 /** 497 * amdgpu_fence_driver_resume - resume the fence driver 498 * for all possible rings. 499 * 500 * @adev: amdgpu device pointer 501 * 502 * Resume the fence driver for all possible rings (all asics). 503 * Not all asics have all rings, so each asic will only 504 * start the fence driver on the rings it has using 505 * amdgpu_fence_driver_start_ring(). 506 * Returns 0 for success. 507 */ 508 void amdgpu_fence_driver_resume(struct amdgpu_device *adev) 509 { 510 int i; 511 512 for (i = 0; i < AMDGPU_MAX_RINGS; i++) { 513 struct amdgpu_ring *ring = adev->rings[i]; 514 if (!ring || !ring->fence_drv.initialized) 515 continue; 516 517 /* enable the interrupt */ 518 amdgpu_irq_get(adev, ring->fence_drv.irq_src, 519 ring->fence_drv.irq_type); 520 } 521 } 522 523 /** 524 * amdgpu_fence_driver_force_completion - force all fence waiter to complete 525 * 526 * @adev: amdgpu device pointer 527 * 528 * In case of GPU reset failure make sure no process keep waiting on fence 529 * that will never complete. 530 */ 531 void amdgpu_fence_driver_force_completion(struct amdgpu_device *adev) 532 { 533 int i; 534 535 for (i = 0; i < AMDGPU_MAX_RINGS; i++) { 536 struct amdgpu_ring *ring = adev->rings[i]; 537 if (!ring || !ring->fence_drv.initialized) 538 continue; 539 540 amdgpu_fence_write(ring, ring->fence_drv.sync_seq); 541 } 542 } 543 544 /* 545 * Common fence implementation 546 */ 547 548 static const char *amdgpu_fence_get_driver_name(struct dma_fence *fence) 549 { 550 return "amdgpu"; 551 } 552 553 static const char *amdgpu_fence_get_timeline_name(struct dma_fence *f) 554 { 555 struct amdgpu_fence *fence = to_amdgpu_fence(f); 556 return (const char *)fence->ring->name; 557 } 558 559 /** 560 * amdgpu_fence_enable_signaling - enable signalling on fence 561 * @fence: fence 562 * 563 * This function is called with fence_queue lock held, and adds a callback 564 * to fence_queue that checks if this fence is signaled, and if so it 565 * signals the fence and removes itself. 566 */ 567 static bool amdgpu_fence_enable_signaling(struct dma_fence *f) 568 { 569 struct amdgpu_fence *fence = to_amdgpu_fence(f); 570 struct amdgpu_ring *ring = fence->ring; 571 572 if (!timer_pending(&ring->fence_drv.fallback_timer)) 573 amdgpu_fence_schedule_fallback(ring); 574 575 DMA_FENCE_TRACE(&fence->base, "armed on ring %i!\n", ring->idx); 576 577 return true; 578 } 579 580 /** 581 * amdgpu_fence_free - free up the fence memory 582 * 583 * @rcu: RCU callback head 584 * 585 * Free up the fence memory after the RCU grace period. 586 */ 587 static void amdgpu_fence_free(struct rcu_head *rcu) 588 { 589 struct dma_fence *f = container_of(rcu, struct dma_fence, rcu); 590 struct amdgpu_fence *fence = to_amdgpu_fence(f); 591 kmem_cache_free(amdgpu_fence_slab, fence); 592 } 593 594 /** 595 * amdgpu_fence_release - callback that fence can be freed 596 * 597 * @fence: fence 598 * 599 * This function is called when the reference count becomes zero. 600 * It just RCU schedules freeing up the fence. 601 */ 602 static void amdgpu_fence_release(struct dma_fence *f) 603 { 604 call_rcu(&f->rcu, amdgpu_fence_free); 605 } 606 607 static const struct dma_fence_ops amdgpu_fence_ops = { 608 .get_driver_name = amdgpu_fence_get_driver_name, 609 .get_timeline_name = amdgpu_fence_get_timeline_name, 610 .enable_signaling = amdgpu_fence_enable_signaling, 611 .wait = dma_fence_default_wait, 612 .release = amdgpu_fence_release, 613 }; 614 615 /* 616 * Fence debugfs 617 */ 618 #if defined(CONFIG_DEBUG_FS) 619 static int amdgpu_debugfs_fence_info(struct seq_file *m, void *data) 620 { 621 struct drm_info_node *node = (struct drm_info_node *)m->private; 622 struct drm_device *dev = node->minor->dev; 623 struct amdgpu_device *adev = dev->dev_private; 624 int i; 625 626 for (i = 0; i < AMDGPU_MAX_RINGS; ++i) { 627 struct amdgpu_ring *ring = adev->rings[i]; 628 if (!ring || !ring->fence_drv.initialized) 629 continue; 630 631 amdgpu_fence_process(ring); 632 633 seq_printf(m, "--- ring %d (%s) ---\n", i, ring->name); 634 seq_printf(m, "Last signaled fence 0x%08x\n", 635 atomic_read(&ring->fence_drv.last_seq)); 636 seq_printf(m, "Last emitted 0x%08x\n", 637 ring->fence_drv.sync_seq); 638 } 639 return 0; 640 } 641 642 /** 643 * amdgpu_debugfs_gpu_reset - manually trigger a gpu reset 644 * 645 * Manually trigger a gpu reset at the next fence wait. 646 */ 647 static int amdgpu_debugfs_gpu_reset(struct seq_file *m, void *data) 648 { 649 struct drm_info_node *node = (struct drm_info_node *) m->private; 650 struct drm_device *dev = node->minor->dev; 651 struct amdgpu_device *adev = dev->dev_private; 652 653 seq_printf(m, "gpu reset\n"); 654 amdgpu_gpu_reset(adev); 655 656 return 0; 657 } 658 659 static const struct drm_info_list amdgpu_debugfs_fence_list[] = { 660 {"amdgpu_fence_info", &amdgpu_debugfs_fence_info, 0, NULL}, 661 {"amdgpu_gpu_reset", &amdgpu_debugfs_gpu_reset, 0, NULL} 662 }; 663 #endif 664 665 int amdgpu_debugfs_fence_init(struct amdgpu_device *adev) 666 { 667 #if defined(CONFIG_DEBUG_FS) 668 return amdgpu_debugfs_add_files(adev, amdgpu_debugfs_fence_list, 2); 669 #else 670 return 0; 671 #endif 672 } 673 674