2 * Copyright 2009 Jerome Glisse.
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:
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.
21 * The above copyright notice and this permission notice (including the
22 * next paragraph) shall be included in all copies or substantial portions
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>
39 #include "amdgpu_trace.h"
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.
54 struct amdgpu_ring *ring;
57 static struct kmem_cache *amdgpu_fence_slab;
59 int amdgpu_fence_slab_init(void)
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)
69 void amdgpu_fence_slab_fini(void)
71 kmem_cache_destroy(amdgpu_fence_slab);
76 static const struct fence_ops amdgpu_fence_ops;
77 static inline struct amdgpu_fence *to_amdgpu_fence(struct fence *f)
79 struct amdgpu_fence *__f = container_of(f, struct amdgpu_fence, base);
81 if (__f->base.ops == &amdgpu_fence_ops)
88 * amdgpu_fence_write - write a fence value
90 * @ring: ring the fence is associated with
91 * @seq: sequence number to write
93 * Writes a fence value to memory (all asics).
95 static void amdgpu_fence_write(struct amdgpu_ring *ring, u32 seq)
97 struct amdgpu_fence_driver *drv = &ring->fence_drv;
100 *drv->cpu_addr = cpu_to_le32(seq);
104 * amdgpu_fence_read - read a fence value
106 * @ring: ring the fence is associated with
108 * Reads a fence value from memory (all asics).
109 * Returns the value of the fence read from memory.
111 static u32 amdgpu_fence_read(struct amdgpu_ring *ring)
113 struct amdgpu_fence_driver *drv = &ring->fence_drv;
117 seq = le32_to_cpu(*drv->cpu_addr);
119 seq = atomic_read(&drv->last_seq);
125 * amdgpu_fence_emit - emit a fence on the requested ring
127 * @ring: ring the fence is associated with
128 * @f: resulting fence object
130 * Emits a fence command on the requested ring (all asics).
131 * Returns 0 on success, -ENOMEM on failure.
133 int amdgpu_fence_emit(struct amdgpu_ring *ring, struct fence **f)
135 struct amdgpu_device *adev = ring->adev;
136 struct amdgpu_fence *fence;
137 struct fence *old, **ptr;
140 fence = kmem_cache_alloc(amdgpu_fence_slab, GFP_KERNEL);
144 seq = ++ring->fence_drv.sync_seq;
146 fence_init(&fence->base, &amdgpu_fence_ops,
147 &ring->fence_drv.lock,
148 adev->fence_context + ring->idx,
150 amdgpu_ring_emit_fence(ring, ring->fence_drv.gpu_addr,
151 seq, AMDGPU_FENCE_FLAG_INT);
153 ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask];
154 /* This function can't be called concurrently anyway, otherwise
155 * emitting the fence would mess up the hardware ring buffer.
157 old = rcu_dereference_protected(*ptr, 1);
158 if (old && !fence_is_signaled(old)) {
159 DRM_INFO("rcu slot is busy\n");
160 fence_wait(old, false);
163 rcu_assign_pointer(*ptr, fence_get(&fence->base));
171 * amdgpu_fence_schedule_fallback - schedule fallback check
173 * @ring: pointer to struct amdgpu_ring
175 * Start a timer as fallback to our interrupts.
177 static void amdgpu_fence_schedule_fallback(struct amdgpu_ring *ring)
179 mod_timer(&ring->fence_drv.fallback_timer,
180 jiffies + AMDGPU_FENCE_JIFFIES_TIMEOUT);
184 * amdgpu_fence_process - check for fence activity
186 * @ring: pointer to struct amdgpu_ring
188 * Checks the current fence value and calculates the last
189 * signalled fence value. Wakes the fence queue if the
190 * sequence number has increased.
192 void amdgpu_fence_process(struct amdgpu_ring *ring)
194 struct amdgpu_fence_driver *drv = &ring->fence_drv;
195 uint32_t seq, last_seq;
199 last_seq = atomic_read(&ring->fence_drv.last_seq);
200 seq = amdgpu_fence_read(ring);
202 } while (atomic_cmpxchg(&drv->last_seq, last_seq, seq) != last_seq);
204 if (seq != ring->fence_drv.sync_seq)
205 amdgpu_fence_schedule_fallback(ring);
207 if (unlikely(seq == last_seq))
210 last_seq &= drv->num_fences_mask;
211 seq &= drv->num_fences_mask;
214 struct fence *fence, **ptr;
217 last_seq &= drv->num_fences_mask;
218 ptr = &drv->fences[last_seq];
220 /* There is always exactly one thread signaling this fence slot */
221 fence = rcu_dereference_protected(*ptr, 1);
222 RCU_INIT_POINTER(*ptr, NULL);
227 r = fence_signal(fence);
229 FENCE_TRACE(fence, "signaled from irq context\n");
234 } while (last_seq != seq);
238 * amdgpu_fence_fallback - fallback for hardware interrupts
240 * @work: delayed work item
242 * Checks for fence activity.
244 static void amdgpu_fence_fallback(unsigned long arg)
246 struct amdgpu_ring *ring = (void *)arg;
248 amdgpu_fence_process(ring);
252 * amdgpu_fence_wait_empty - wait for all fences to signal
254 * @adev: amdgpu device pointer
255 * @ring: ring index the fence is associated with
257 * Wait for all fences on the requested ring to signal (all asics).
258 * Returns 0 if the fences have passed, error for all other cases.
260 int amdgpu_fence_wait_empty(struct amdgpu_ring *ring)
262 uint64_t seq = ACCESS_ONCE(ring->fence_drv.sync_seq);
263 struct fence *fence, **ptr;
269 ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask];
271 fence = rcu_dereference(*ptr);
272 if (!fence || !fence_get_rcu(fence)) {
278 r = fence_wait(fence, false);
284 * amdgpu_fence_count_emitted - get the count of emitted fences
286 * @ring: ring the fence is associated with
288 * Get the number of fences emitted on the requested ring (all asics).
289 * Returns the number of emitted fences on the ring. Used by the
290 * dynpm code to ring track activity.
292 unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring)
296 /* We are not protected by ring lock when reading the last sequence
297 * but it's ok to report slightly wrong fence count here.
299 amdgpu_fence_process(ring);
300 emitted = 0x100000000ull;
301 emitted -= atomic_read(&ring->fence_drv.last_seq);
302 emitted += ACCESS_ONCE(ring->fence_drv.sync_seq);
303 return lower_32_bits(emitted);
307 * amdgpu_fence_driver_start_ring - make the fence driver
308 * ready for use on the requested ring.
310 * @ring: ring to start the fence driver on
311 * @irq_src: interrupt source to use for this ring
312 * @irq_type: interrupt type to use for this ring
314 * Make the fence driver ready for processing (all asics).
315 * Not all asics have all rings, so each asic will only
316 * start the fence driver on the rings it has.
317 * Returns 0 for success, errors for failure.
319 int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
320 struct amdgpu_irq_src *irq_src,
323 struct amdgpu_device *adev = ring->adev;
326 if (ring != &adev->uvd.ring) {
327 ring->fence_drv.cpu_addr = &adev->wb.wb[ring->fence_offs];
328 ring->fence_drv.gpu_addr = adev->wb.gpu_addr + (ring->fence_offs * 4);
330 /* put fence directly behind firmware */
331 index = ALIGN(adev->uvd.fw->size, 8);
332 ring->fence_drv.cpu_addr = adev->uvd.cpu_addr + index;
333 ring->fence_drv.gpu_addr = adev->uvd.gpu_addr + index;
335 amdgpu_fence_write(ring, atomic_read(&ring->fence_drv.last_seq));
336 amdgpu_irq_get(adev, irq_src, irq_type);
338 ring->fence_drv.irq_src = irq_src;
339 ring->fence_drv.irq_type = irq_type;
340 ring->fence_drv.initialized = true;
342 dev_info(adev->dev, "fence driver on ring %d use gpu addr 0x%016llx, "
343 "cpu addr 0x%p\n", ring->idx,
344 ring->fence_drv.gpu_addr, ring->fence_drv.cpu_addr);
349 * amdgpu_fence_driver_init_ring - init the fence driver
350 * for the requested ring.
352 * @ring: ring to init the fence driver on
353 * @num_hw_submission: number of entries on the hardware queue
355 * Init the fence driver for the requested ring (all asics).
356 * Helper function for amdgpu_fence_driver_init().
358 int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring,
359 unsigned num_hw_submission)
364 /* Check that num_hw_submission is a power of two */
365 if ((num_hw_submission & (num_hw_submission - 1)) != 0)
368 ring->fence_drv.cpu_addr = NULL;
369 ring->fence_drv.gpu_addr = 0;
370 ring->fence_drv.sync_seq = 0;
371 atomic_set(&ring->fence_drv.last_seq, 0);
372 ring->fence_drv.initialized = false;
374 setup_timer(&ring->fence_drv.fallback_timer, amdgpu_fence_fallback,
375 (unsigned long)ring);
377 ring->fence_drv.num_fences_mask = num_hw_submission * 2 - 1;
378 spin_lock_init(&ring->fence_drv.lock);
379 ring->fence_drv.fences = kcalloc(num_hw_submission * 2, sizeof(void *),
381 if (!ring->fence_drv.fences)
384 timeout = msecs_to_jiffies(amdgpu_lockup_timeout);
388 * Delayed workqueue cannot use it directly,
389 * so the scheduler will not use delayed workqueue if
390 * MAX_SCHEDULE_TIMEOUT is set.
391 * Currently keep it simple and silly.
393 timeout = MAX_SCHEDULE_TIMEOUT;
395 r = amd_sched_init(&ring->sched, &amdgpu_sched_ops,
397 timeout, ring->name);
399 DRM_ERROR("Failed to create scheduler on ring %s.\n",
408 * amdgpu_fence_driver_init - init the fence driver
409 * for all possible rings.
411 * @adev: amdgpu device pointer
413 * Init the fence driver for all possible rings (all asics).
414 * Not all asics have all rings, so each asic will only
415 * start the fence driver on the rings it has using
416 * amdgpu_fence_driver_start_ring().
417 * Returns 0 for success.
419 int amdgpu_fence_driver_init(struct amdgpu_device *adev)
421 if (amdgpu_debugfs_fence_init(adev))
422 dev_err(adev->dev, "fence debugfs file creation failed\n");
428 * amdgpu_fence_driver_fini - tear down the fence driver
429 * for all possible rings.
431 * @adev: amdgpu device pointer
433 * Tear down the fence driver for all possible rings (all asics).
435 void amdgpu_fence_driver_fini(struct amdgpu_device *adev)
440 for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
441 struct amdgpu_ring *ring = adev->rings[i];
443 if (!ring || !ring->fence_drv.initialized)
445 r = amdgpu_fence_wait_empty(ring);
447 /* no need to trigger GPU reset as we are unloading */
448 amdgpu_fence_driver_force_completion(adev);
450 amdgpu_irq_put(adev, ring->fence_drv.irq_src,
451 ring->fence_drv.irq_type);
452 amd_sched_fini(&ring->sched);
453 del_timer_sync(&ring->fence_drv.fallback_timer);
454 for (j = 0; j <= ring->fence_drv.num_fences_mask; ++j)
455 fence_put(ring->fence_drv.fences[j]);
456 kfree(ring->fence_drv.fences);
457 ring->fence_drv.fences = NULL;
458 ring->fence_drv.initialized = false;
463 * amdgpu_fence_driver_suspend - suspend the fence driver
464 * for all possible rings.
466 * @adev: amdgpu device pointer
468 * Suspend the fence driver for all possible rings (all asics).
470 void amdgpu_fence_driver_suspend(struct amdgpu_device *adev)
474 for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
475 struct amdgpu_ring *ring = adev->rings[i];
476 if (!ring || !ring->fence_drv.initialized)
479 /* wait for gpu to finish processing current batch */
480 r = amdgpu_fence_wait_empty(ring);
482 /* delay GPU reset to resume */
483 amdgpu_fence_driver_force_completion(adev);
486 /* disable the interrupt */
487 amdgpu_irq_put(adev, ring->fence_drv.irq_src,
488 ring->fence_drv.irq_type);
493 * amdgpu_fence_driver_resume - resume the fence driver
494 * for all possible rings.
496 * @adev: amdgpu device pointer
498 * Resume the fence driver for all possible rings (all asics).
499 * Not all asics have all rings, so each asic will only
500 * start the fence driver on the rings it has using
501 * amdgpu_fence_driver_start_ring().
502 * Returns 0 for success.
504 void amdgpu_fence_driver_resume(struct amdgpu_device *adev)
508 for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
509 struct amdgpu_ring *ring = adev->rings[i];
510 if (!ring || !ring->fence_drv.initialized)
513 /* enable the interrupt */
514 amdgpu_irq_get(adev, ring->fence_drv.irq_src,
515 ring->fence_drv.irq_type);
520 * amdgpu_fence_driver_force_completion - force all fence waiter to complete
522 * @adev: amdgpu device pointer
524 * In case of GPU reset failure make sure no process keep waiting on fence
525 * that will never complete.
527 void amdgpu_fence_driver_force_completion(struct amdgpu_device *adev)
531 for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
532 struct amdgpu_ring *ring = adev->rings[i];
533 if (!ring || !ring->fence_drv.initialized)
536 amdgpu_fence_write(ring, ring->fence_drv.sync_seq);
541 * Common fence implementation
544 static const char *amdgpu_fence_get_driver_name(struct fence *fence)
549 static const char *amdgpu_fence_get_timeline_name(struct fence *f)
551 struct amdgpu_fence *fence = to_amdgpu_fence(f);
552 return (const char *)fence->ring->name;
556 * amdgpu_fence_enable_signaling - enable signalling on fence
559 * This function is called with fence_queue lock held, and adds a callback
560 * to fence_queue that checks if this fence is signaled, and if so it
561 * signals the fence and removes itself.
563 static bool amdgpu_fence_enable_signaling(struct fence *f)
565 struct amdgpu_fence *fence = to_amdgpu_fence(f);
566 struct amdgpu_ring *ring = fence->ring;
568 if (!timer_pending(&ring->fence_drv.fallback_timer))
569 amdgpu_fence_schedule_fallback(ring);
571 FENCE_TRACE(&fence->base, "armed on ring %i!\n", ring->idx);
577 * amdgpu_fence_free - free up the fence memory
579 * @rcu: RCU callback head
581 * Free up the fence memory after the RCU grace period.
583 static void amdgpu_fence_free(struct rcu_head *rcu)
585 struct fence *f = container_of(rcu, struct fence, rcu);
586 struct amdgpu_fence *fence = to_amdgpu_fence(f);
587 kmem_cache_free(amdgpu_fence_slab, fence);
591 * amdgpu_fence_release - callback that fence can be freed
595 * This function is called when the reference count becomes zero.
596 * It just RCU schedules freeing up the fence.
598 static void amdgpu_fence_release(struct fence *f)
600 call_rcu(&f->rcu, amdgpu_fence_free);
603 static const struct fence_ops amdgpu_fence_ops = {
604 .get_driver_name = amdgpu_fence_get_driver_name,
605 .get_timeline_name = amdgpu_fence_get_timeline_name,
606 .enable_signaling = amdgpu_fence_enable_signaling,
607 .wait = fence_default_wait,
608 .release = amdgpu_fence_release,
614 #if defined(CONFIG_DEBUG_FS)
615 static int amdgpu_debugfs_fence_info(struct seq_file *m, void *data)
617 struct drm_info_node *node = (struct drm_info_node *)m->private;
618 struct drm_device *dev = node->minor->dev;
619 struct amdgpu_device *adev = dev->dev_private;
622 for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
623 struct amdgpu_ring *ring = adev->rings[i];
624 if (!ring || !ring->fence_drv.initialized)
627 amdgpu_fence_process(ring);
629 seq_printf(m, "--- ring %d (%s) ---\n", i, ring->name);
630 seq_printf(m, "Last signaled fence 0x%08x\n",
631 atomic_read(&ring->fence_drv.last_seq));
632 seq_printf(m, "Last emitted 0x%08x\n",
633 ring->fence_drv.sync_seq);
639 * amdgpu_debugfs_gpu_reset - manually trigger a gpu reset
641 * Manually trigger a gpu reset at the next fence wait.
643 static int amdgpu_debugfs_gpu_reset(struct seq_file *m, void *data)
645 struct drm_info_node *node = (struct drm_info_node *) m->private;
646 struct drm_device *dev = node->minor->dev;
647 struct amdgpu_device *adev = dev->dev_private;
649 seq_printf(m, "gpu reset\n");
650 amdgpu_gpu_reset(adev);
655 static const struct drm_info_list amdgpu_debugfs_fence_list[] = {
656 {"amdgpu_fence_info", &amdgpu_debugfs_fence_info, 0, NULL},
657 {"amdgpu_gpu_reset", &amdgpu_debugfs_gpu_reset, 0, NULL}
661 int amdgpu_debugfs_fence_init(struct amdgpu_device *adev)
663 #if defined(CONFIG_DEBUG_FS)
664 return amdgpu_debugfs_add_files(adev, amdgpu_debugfs_fence_list, 2);