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