1 /*
2  * Copyright 2008 Advanced Micro Devices, Inc.
3  * Copyright 2008 Red Hat Inc.
4  * Copyright 2009 Jerome Glisse.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: Dave Airlie
25  *          Alex Deucher
26  *          Jerome Glisse
27  *          Christian König
28  */
29 #include <linux/seq_file.h>
30 #include <linux/slab.h>
31 #include <drm/drmP.h>
32 #include <drm/radeon_drm.h>
33 #include "radeon_reg.h"
34 #include "radeon.h"
35 #include "atom.h"
36 
37 /*
38  * IB
39  * IBs (Indirect Buffers) and areas of GPU accessible memory where
40  * commands are stored.  You can put a pointer to the IB in the
41  * command ring and the hw will fetch the commands from the IB
42  * and execute them.  Generally userspace acceleration drivers
43  * produce command buffers which are send to the kernel and
44  * put in IBs for execution by the requested ring.
45  */
46 static int radeon_debugfs_sa_init(struct radeon_device *rdev);
47 
48 /**
49  * radeon_ib_get - request an IB (Indirect Buffer)
50  *
51  * @rdev: radeon_device pointer
52  * @ring: ring index the IB is associated with
53  * @ib: IB object returned
54  * @size: requested IB size
55  *
56  * Request an IB (all asics).  IBs are allocated using the
57  * suballocator.
58  * Returns 0 on success, error on failure.
59  */
60 int radeon_ib_get(struct radeon_device *rdev, int ring,
61 		  struct radeon_ib *ib, struct radeon_vm *vm,
62 		  unsigned size)
63 {
64 	int r;
65 
66 	r = radeon_sa_bo_new(rdev, &rdev->ring_tmp_bo, &ib->sa_bo, size, 256, true);
67 	if (r) {
68 		dev_err(rdev->dev, "failed to get a new IB (%d)\n", r);
69 		return r;
70 	}
71 
72 	r = radeon_semaphore_create(rdev, &ib->semaphore);
73 	if (r) {
74 		return r;
75 	}
76 
77 	ib->ring = ring;
78 	ib->fence = NULL;
79 	ib->ptr = radeon_sa_bo_cpu_addr(ib->sa_bo);
80 	ib->vm = vm;
81 	if (vm) {
82 		/* ib pool is bound at RADEON_VA_IB_OFFSET in virtual address
83 		 * space and soffset is the offset inside the pool bo
84 		 */
85 		ib->gpu_addr = ib->sa_bo->soffset + RADEON_VA_IB_OFFSET;
86 	} else {
87 		ib->gpu_addr = radeon_sa_bo_gpu_addr(ib->sa_bo);
88 	}
89 	ib->is_const_ib = false;
90 
91 	return 0;
92 }
93 
94 /**
95  * radeon_ib_free - free an IB (Indirect Buffer)
96  *
97  * @rdev: radeon_device pointer
98  * @ib: IB object to free
99  *
100  * Free an IB (all asics).
101  */
102 void radeon_ib_free(struct radeon_device *rdev, struct radeon_ib *ib)
103 {
104 	radeon_semaphore_free(rdev, &ib->semaphore, ib->fence);
105 	radeon_sa_bo_free(rdev, &ib->sa_bo, ib->fence);
106 	radeon_fence_unref(&ib->fence);
107 }
108 
109 /**
110  * radeon_ib_schedule - schedule an IB (Indirect Buffer) on the ring
111  *
112  * @rdev: radeon_device pointer
113  * @ib: IB object to schedule
114  * @const_ib: Const IB to schedule (SI only)
115  *
116  * Schedule an IB on the associated ring (all asics).
117  * Returns 0 on success, error on failure.
118  *
119  * On SI, there are two parallel engines fed from the primary ring,
120  * the CE (Constant Engine) and the DE (Drawing Engine).  Since
121  * resource descriptors have moved to memory, the CE allows you to
122  * prime the caches while the DE is updating register state so that
123  * the resource descriptors will be already in cache when the draw is
124  * processed.  To accomplish this, the userspace driver submits two
125  * IBs, one for the CE and one for the DE.  If there is a CE IB (called
126  * a CONST_IB), it will be put on the ring prior to the DE IB.  Prior
127  * to SI there was just a DE IB.
128  */
129 int radeon_ib_schedule(struct radeon_device *rdev, struct radeon_ib *ib,
130 		       struct radeon_ib *const_ib)
131 {
132 	struct radeon_ring *ring = &rdev->ring[ib->ring];
133 	int r = 0;
134 
135 	if (!ib->length_dw || !ring->ready) {
136 		/* TODO: Nothings in the ib we should report. */
137 		dev_err(rdev->dev, "couldn't schedule ib\n");
138 		return -EINVAL;
139 	}
140 
141 	/* 64 dwords should be enough for fence too */
142 	r = radeon_ring_lock(rdev, ring, 64 + RADEON_NUM_RINGS * 8);
143 	if (r) {
144 		dev_err(rdev->dev, "scheduling IB failed (%d).\n", r);
145 		return r;
146 	}
147 
148 	/* sync with other rings */
149 	r = radeon_semaphore_sync_rings(rdev, ib->semaphore, ib->ring);
150 	if (r) {
151 		dev_err(rdev->dev, "failed to sync rings (%d)\n", r);
152 		radeon_ring_unlock_undo(rdev, ring);
153 		return r;
154 	}
155 
156 	/* if we can't remember our last VM flush then flush now! */
157 	/* XXX figure out why we have to flush for every IB */
158 	if (ib->vm /*&& !ib->vm->last_flush*/) {
159 		radeon_ring_vm_flush(rdev, ib->ring, ib->vm);
160 	}
161 	if (const_ib) {
162 		radeon_ring_ib_execute(rdev, const_ib->ring, const_ib);
163 		radeon_semaphore_free(rdev, &const_ib->semaphore, NULL);
164 	}
165 	radeon_ring_ib_execute(rdev, ib->ring, ib);
166 	r = radeon_fence_emit(rdev, &ib->fence, ib->ring);
167 	if (r) {
168 		dev_err(rdev->dev, "failed to emit fence for new IB (%d)\n", r);
169 		radeon_ring_unlock_undo(rdev, ring);
170 		return r;
171 	}
172 	if (const_ib) {
173 		const_ib->fence = radeon_fence_ref(ib->fence);
174 	}
175 	/* we just flushed the VM, remember that */
176 	if (ib->vm && !ib->vm->last_flush) {
177 		ib->vm->last_flush = radeon_fence_ref(ib->fence);
178 	}
179 	radeon_ring_unlock_commit(rdev, ring);
180 	return 0;
181 }
182 
183 /**
184  * radeon_ib_pool_init - Init the IB (Indirect Buffer) pool
185  *
186  * @rdev: radeon_device pointer
187  *
188  * Initialize the suballocator to manage a pool of memory
189  * for use as IBs (all asics).
190  * Returns 0 on success, error on failure.
191  */
192 int radeon_ib_pool_init(struct radeon_device *rdev)
193 {
194 	int r;
195 
196 	if (rdev->ib_pool_ready) {
197 		return 0;
198 	}
199 	r = radeon_sa_bo_manager_init(rdev, &rdev->ring_tmp_bo,
200 				      RADEON_IB_POOL_SIZE*64*1024,
201 				      RADEON_GPU_PAGE_SIZE,
202 				      RADEON_GEM_DOMAIN_GTT);
203 	if (r) {
204 		return r;
205 	}
206 
207 	r = radeon_sa_bo_manager_start(rdev, &rdev->ring_tmp_bo);
208 	if (r) {
209 		return r;
210 	}
211 
212 	rdev->ib_pool_ready = true;
213 	if (radeon_debugfs_sa_init(rdev)) {
214 		dev_err(rdev->dev, "failed to register debugfs file for SA\n");
215 	}
216 	return 0;
217 }
218 
219 /**
220  * radeon_ib_pool_fini - Free the IB (Indirect Buffer) pool
221  *
222  * @rdev: radeon_device pointer
223  *
224  * Tear down the suballocator managing the pool of memory
225  * for use as IBs (all asics).
226  */
227 void radeon_ib_pool_fini(struct radeon_device *rdev)
228 {
229 	if (rdev->ib_pool_ready) {
230 		radeon_sa_bo_manager_suspend(rdev, &rdev->ring_tmp_bo);
231 		radeon_sa_bo_manager_fini(rdev, &rdev->ring_tmp_bo);
232 		rdev->ib_pool_ready = false;
233 	}
234 }
235 
236 /**
237  * radeon_ib_ring_tests - test IBs on the rings
238  *
239  * @rdev: radeon_device pointer
240  *
241  * Test an IB (Indirect Buffer) on each ring.
242  * If the test fails, disable the ring.
243  * Returns 0 on success, error if the primary GFX ring
244  * IB test fails.
245  */
246 int radeon_ib_ring_tests(struct radeon_device *rdev)
247 {
248 	unsigned i;
249 	int r;
250 
251 	for (i = 0; i < RADEON_NUM_RINGS; ++i) {
252 		struct radeon_ring *ring = &rdev->ring[i];
253 
254 		if (!ring->ready)
255 			continue;
256 
257 		r = radeon_ib_test(rdev, i, ring);
258 		if (r) {
259 			ring->ready = false;
260 
261 			if (i == RADEON_RING_TYPE_GFX_INDEX) {
262 				/* oh, oh, that's really bad */
263 				DRM_ERROR("radeon: failed testing IB on GFX ring (%d).\n", r);
264 		                rdev->accel_working = false;
265 				return r;
266 
267 			} else {
268 				/* still not good, but we can live with it */
269 				DRM_ERROR("radeon: failed testing IB on ring %d (%d).\n", i, r);
270 			}
271 		}
272 	}
273 	return 0;
274 }
275 
276 /*
277  * Rings
278  * Most engines on the GPU are fed via ring buffers.  Ring
279  * buffers are areas of GPU accessible memory that the host
280  * writes commands into and the GPU reads commands out of.
281  * There is a rptr (read pointer) that determines where the
282  * GPU is currently reading, and a wptr (write pointer)
283  * which determines where the host has written.  When the
284  * pointers are equal, the ring is idle.  When the host
285  * writes commands to the ring buffer, it increments the
286  * wptr.  The GPU then starts fetching commands and executes
287  * them until the pointers are equal again.
288  */
289 static int radeon_debugfs_ring_init(struct radeon_device *rdev, struct radeon_ring *ring);
290 
291 /**
292  * radeon_ring_write - write a value to the ring
293  *
294  * @ring: radeon_ring structure holding ring information
295  * @v: dword (dw) value to write
296  *
297  * Write a value to the requested ring buffer (all asics).
298  */
299 void radeon_ring_write(struct radeon_ring *ring, uint32_t v)
300 {
301 #if DRM_DEBUG_CODE
302 	if (ring->count_dw <= 0) {
303 		DRM_ERROR("radeon: writing more dwords to the ring than expected!\n");
304 	}
305 #endif
306 	ring->ring[ring->wptr++] = v;
307 	ring->wptr &= ring->ptr_mask;
308 	ring->count_dw--;
309 	ring->ring_free_dw--;
310 }
311 
312 /**
313  * radeon_ring_supports_scratch_reg - check if the ring supports
314  * writing to scratch registers
315  *
316  * @rdev: radeon_device pointer
317  * @ring: radeon_ring structure holding ring information
318  *
319  * Check if a specific ring supports writing to scratch registers (all asics).
320  * Returns true if the ring supports writing to scratch regs, false if not.
321  */
322 bool radeon_ring_supports_scratch_reg(struct radeon_device *rdev,
323 				      struct radeon_ring *ring)
324 {
325 	switch (ring->idx) {
326 	case RADEON_RING_TYPE_GFX_INDEX:
327 	case CAYMAN_RING_TYPE_CP1_INDEX:
328 	case CAYMAN_RING_TYPE_CP2_INDEX:
329 		return true;
330 	default:
331 		return false;
332 	}
333 }
334 
335 /**
336  * radeon_ring_free_size - update the free size
337  *
338  * @rdev: radeon_device pointer
339  * @ring: radeon_ring structure holding ring information
340  *
341  * Update the free dw slots in the ring buffer (all asics).
342  */
343 void radeon_ring_free_size(struct radeon_device *rdev, struct radeon_ring *ring)
344 {
345 	ring->rptr = radeon_ring_get_rptr(rdev, ring);
346 	/* This works because ring_size is a power of 2 */
347 	ring->ring_free_dw = (ring->rptr + (ring->ring_size / 4));
348 	ring->ring_free_dw -= ring->wptr;
349 	ring->ring_free_dw &= ring->ptr_mask;
350 	if (!ring->ring_free_dw) {
351 		ring->ring_free_dw = ring->ring_size / 4;
352 	}
353 }
354 
355 /**
356  * radeon_ring_alloc - allocate space on the ring buffer
357  *
358  * @rdev: radeon_device pointer
359  * @ring: radeon_ring structure holding ring information
360  * @ndw: number of dwords to allocate in the ring buffer
361  *
362  * Allocate @ndw dwords in the ring buffer (all asics).
363  * Returns 0 on success, error on failure.
364  */
365 int radeon_ring_alloc(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ndw)
366 {
367 	int r;
368 
369 	/* make sure we aren't trying to allocate more space than there is on the ring */
370 	if (ndw > (ring->ring_size / 4))
371 		return -ENOMEM;
372 	/* Align requested size with padding so unlock_commit can
373 	 * pad safely */
374 	radeon_ring_free_size(rdev, ring);
375 	if (ring->ring_free_dw == (ring->ring_size / 4)) {
376 		/* This is an empty ring update lockup info to avoid
377 		 * false positive.
378 		 */
379 		radeon_ring_lockup_update(ring);
380 	}
381 	ndw = (ndw + ring->align_mask) & ~ring->align_mask;
382 	while (ndw > (ring->ring_free_dw - 1)) {
383 		radeon_ring_free_size(rdev, ring);
384 		if (ndw < ring->ring_free_dw) {
385 			break;
386 		}
387 		r = radeon_fence_wait_next_locked(rdev, ring->idx);
388 		if (r)
389 			return r;
390 	}
391 	ring->count_dw = ndw;
392 	ring->wptr_old = ring->wptr;
393 	return 0;
394 }
395 
396 /**
397  * radeon_ring_lock - lock the ring and allocate space on it
398  *
399  * @rdev: radeon_device pointer
400  * @ring: radeon_ring structure holding ring information
401  * @ndw: number of dwords to allocate in the ring buffer
402  *
403  * Lock the ring and allocate @ndw dwords in the ring buffer
404  * (all asics).
405  * Returns 0 on success, error on failure.
406  */
407 int radeon_ring_lock(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ndw)
408 {
409 	int r;
410 
411 	mutex_lock(&rdev->ring_lock);
412 	r = radeon_ring_alloc(rdev, ring, ndw);
413 	if (r) {
414 		mutex_unlock(&rdev->ring_lock);
415 		return r;
416 	}
417 	return 0;
418 }
419 
420 /**
421  * radeon_ring_commit - tell the GPU to execute the new
422  * commands on the ring buffer
423  *
424  * @rdev: radeon_device pointer
425  * @ring: radeon_ring structure holding ring information
426  *
427  * Update the wptr (write pointer) to tell the GPU to
428  * execute new commands on the ring buffer (all asics).
429  */
430 void radeon_ring_commit(struct radeon_device *rdev, struct radeon_ring *ring)
431 {
432 	/* We pad to match fetch size */
433 	while (ring->wptr & ring->align_mask) {
434 		radeon_ring_write(ring, ring->nop);
435 	}
436 	mb();
437 	radeon_ring_set_wptr(rdev, ring);
438 }
439 
440 /**
441  * radeon_ring_unlock_commit - tell the GPU to execute the new
442  * commands on the ring buffer and unlock it
443  *
444  * @rdev: radeon_device pointer
445  * @ring: radeon_ring structure holding ring information
446  *
447  * Call radeon_ring_commit() then unlock the ring (all asics).
448  */
449 void radeon_ring_unlock_commit(struct radeon_device *rdev, struct radeon_ring *ring)
450 {
451 	radeon_ring_commit(rdev, ring);
452 	mutex_unlock(&rdev->ring_lock);
453 }
454 
455 /**
456  * radeon_ring_undo - reset the wptr
457  *
458  * @ring: radeon_ring structure holding ring information
459  *
460  * Reset the driver's copy of the wptr (all asics).
461  */
462 void radeon_ring_undo(struct radeon_ring *ring)
463 {
464 	ring->wptr = ring->wptr_old;
465 }
466 
467 /**
468  * radeon_ring_unlock_undo - reset the wptr and unlock the ring
469  *
470  * @ring: radeon_ring structure holding ring information
471  *
472  * Call radeon_ring_undo() then unlock the ring (all asics).
473  */
474 void radeon_ring_unlock_undo(struct radeon_device *rdev, struct radeon_ring *ring)
475 {
476 	radeon_ring_undo(ring);
477 	mutex_unlock(&rdev->ring_lock);
478 }
479 
480 /**
481  * radeon_ring_force_activity - add some nop packets to the ring
482  *
483  * @rdev: radeon_device pointer
484  * @ring: radeon_ring structure holding ring information
485  *
486  * Add some nop packets to the ring to force activity (all asics).
487  * Used for lockup detection to see if the rptr is advancing.
488  */
489 void radeon_ring_force_activity(struct radeon_device *rdev, struct radeon_ring *ring)
490 {
491 	int r;
492 
493 	radeon_ring_free_size(rdev, ring);
494 	if (ring->rptr == ring->wptr) {
495 		r = radeon_ring_alloc(rdev, ring, 1);
496 		if (!r) {
497 			radeon_ring_write(ring, ring->nop);
498 			radeon_ring_commit(rdev, ring);
499 		}
500 	}
501 }
502 
503 /**
504  * radeon_ring_lockup_update - update lockup variables
505  *
506  * @ring: radeon_ring structure holding ring information
507  *
508  * Update the last rptr value and timestamp (all asics).
509  */
510 void radeon_ring_lockup_update(struct radeon_ring *ring)
511 {
512 	ring->last_rptr = ring->rptr;
513 	ring->last_activity = jiffies;
514 }
515 
516 /**
517  * radeon_ring_test_lockup() - check if ring is lockedup by recording information
518  * @rdev:       radeon device structure
519  * @ring:       radeon_ring structure holding ring information
520  *
521  * We don't need to initialize the lockup tracking information as we will either
522  * have CP rptr to a different value of jiffies wrap around which will force
523  * initialization of the lockup tracking informations.
524  *
525  * A possible false positivie is if we get call after while and last_cp_rptr ==
526  * the current CP rptr, even if it's unlikely it might happen. To avoid this
527  * if the elapsed time since last call is bigger than 2 second than we return
528  * false and update the tracking information. Due to this the caller must call
529  * radeon_ring_test_lockup several time in less than 2sec for lockup to be reported
530  * the fencing code should be cautious about that.
531  *
532  * Caller should write to the ring to force CP to do something so we don't get
533  * false positive when CP is just gived nothing to do.
534  *
535  **/
536 bool radeon_ring_test_lockup(struct radeon_device *rdev, struct radeon_ring *ring)
537 {
538 	unsigned long cjiffies, elapsed;
539 
540 	cjiffies = jiffies;
541 	if (!time_after(cjiffies, ring->last_activity)) {
542 		/* likely a wrap around */
543 		radeon_ring_lockup_update(ring);
544 		return false;
545 	}
546 	ring->rptr = radeon_ring_get_rptr(rdev, ring);
547 	if (ring->rptr != ring->last_rptr) {
548 		/* CP is still working no lockup */
549 		radeon_ring_lockup_update(ring);
550 		return false;
551 	}
552 	elapsed = jiffies_to_msecs(cjiffies - ring->last_activity);
553 	if (radeon_lockup_timeout && elapsed >= radeon_lockup_timeout) {
554 		dev_err(rdev->dev, "GPU lockup CP stall for more than %lumsec\n", elapsed);
555 		return true;
556 	}
557 	/* give a chance to the GPU ... */
558 	return false;
559 }
560 
561 /**
562  * radeon_ring_backup - Back up the content of a ring
563  *
564  * @rdev: radeon_device pointer
565  * @ring: the ring we want to back up
566  *
567  * Saves all unprocessed commits from a ring, returns the number of dwords saved.
568  */
569 unsigned radeon_ring_backup(struct radeon_device *rdev, struct radeon_ring *ring,
570 			    uint32_t **data)
571 {
572 	unsigned size, ptr, i;
573 
574 	/* just in case lock the ring */
575 	mutex_lock(&rdev->ring_lock);
576 	*data = NULL;
577 
578 	if (ring->ring_obj == NULL) {
579 		mutex_unlock(&rdev->ring_lock);
580 		return 0;
581 	}
582 
583 	/* it doesn't make sense to save anything if all fences are signaled */
584 	if (!radeon_fence_count_emitted(rdev, ring->idx)) {
585 		mutex_unlock(&rdev->ring_lock);
586 		return 0;
587 	}
588 
589 	/* calculate the number of dw on the ring */
590 	if (ring->rptr_save_reg)
591 		ptr = RREG32(ring->rptr_save_reg);
592 	else if (rdev->wb.enabled)
593 		ptr = le32_to_cpu(*ring->next_rptr_cpu_addr);
594 	else {
595 		/* no way to read back the next rptr */
596 		mutex_unlock(&rdev->ring_lock);
597 		return 0;
598 	}
599 
600 	size = ring->wptr + (ring->ring_size / 4);
601 	size -= ptr;
602 	size &= ring->ptr_mask;
603 	if (size == 0) {
604 		mutex_unlock(&rdev->ring_lock);
605 		return 0;
606 	}
607 
608 	/* and then save the content of the ring */
609 	*data = kmalloc_array(size, sizeof(uint32_t), GFP_KERNEL);
610 	if (!*data) {
611 		mutex_unlock(&rdev->ring_lock);
612 		return 0;
613 	}
614 	for (i = 0; i < size; ++i) {
615 		(*data)[i] = ring->ring[ptr++];
616 		ptr &= ring->ptr_mask;
617 	}
618 
619 	mutex_unlock(&rdev->ring_lock);
620 	return size;
621 }
622 
623 /**
624  * radeon_ring_restore - append saved commands to the ring again
625  *
626  * @rdev: radeon_device pointer
627  * @ring: ring to append commands to
628  * @size: number of dwords we want to write
629  * @data: saved commands
630  *
631  * Allocates space on the ring and restore the previously saved commands.
632  */
633 int radeon_ring_restore(struct radeon_device *rdev, struct radeon_ring *ring,
634 			unsigned size, uint32_t *data)
635 {
636 	int i, r;
637 
638 	if (!size || !data)
639 		return 0;
640 
641 	/* restore the saved ring content */
642 	r = radeon_ring_lock(rdev, ring, size);
643 	if (r)
644 		return r;
645 
646 	for (i = 0; i < size; ++i) {
647 		radeon_ring_write(ring, data[i]);
648 	}
649 
650 	radeon_ring_unlock_commit(rdev, ring);
651 	kfree(data);
652 	return 0;
653 }
654 
655 /**
656  * radeon_ring_init - init driver ring struct.
657  *
658  * @rdev: radeon_device pointer
659  * @ring: radeon_ring structure holding ring information
660  * @ring_size: size of the ring
661  * @rptr_offs: offset of the rptr writeback location in the WB buffer
662  * @nop: nop packet for this ring
663  *
664  * Initialize the driver information for the selected ring (all asics).
665  * Returns 0 on success, error on failure.
666  */
667 int radeon_ring_init(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ring_size,
668 		     unsigned rptr_offs, u32 nop)
669 {
670 	int r;
671 
672 	ring->ring_size = ring_size;
673 	ring->rptr_offs = rptr_offs;
674 	ring->nop = nop;
675 	/* Allocate ring buffer */
676 	if (ring->ring_obj == NULL) {
677 		r = radeon_bo_create(rdev, ring->ring_size, PAGE_SIZE, true,
678 				     RADEON_GEM_DOMAIN_GTT,
679 				     NULL, &ring->ring_obj);
680 		if (r) {
681 			dev_err(rdev->dev, "(%d) ring create failed\n", r);
682 			return r;
683 		}
684 		r = radeon_bo_reserve(ring->ring_obj, false);
685 		if (unlikely(r != 0))
686 			return r;
687 		r = radeon_bo_pin(ring->ring_obj, RADEON_GEM_DOMAIN_GTT,
688 					&ring->gpu_addr);
689 		if (r) {
690 			radeon_bo_unreserve(ring->ring_obj);
691 			dev_err(rdev->dev, "(%d) ring pin failed\n", r);
692 			return r;
693 		}
694 		r = radeon_bo_kmap(ring->ring_obj,
695 				       (void **)&ring->ring);
696 		radeon_bo_unreserve(ring->ring_obj);
697 		if (r) {
698 			dev_err(rdev->dev, "(%d) ring map failed\n", r);
699 			return r;
700 		}
701 	}
702 	ring->ptr_mask = (ring->ring_size / 4) - 1;
703 	ring->ring_free_dw = ring->ring_size / 4;
704 	if (rdev->wb.enabled) {
705 		u32 index = RADEON_WB_RING0_NEXT_RPTR + (ring->idx * 4);
706 		ring->next_rptr_gpu_addr = rdev->wb.gpu_addr + index;
707 		ring->next_rptr_cpu_addr = &rdev->wb.wb[index/4];
708 	}
709 	if (radeon_debugfs_ring_init(rdev, ring)) {
710 		DRM_ERROR("Failed to register debugfs file for rings !\n");
711 	}
712 	radeon_ring_lockup_update(ring);
713 	return 0;
714 }
715 
716 /**
717  * radeon_ring_fini - tear down the driver ring struct.
718  *
719  * @rdev: radeon_device pointer
720  * @ring: radeon_ring structure holding ring information
721  *
722  * Tear down the driver information for the selected ring (all asics).
723  */
724 void radeon_ring_fini(struct radeon_device *rdev, struct radeon_ring *ring)
725 {
726 	int r;
727 	struct radeon_bo *ring_obj;
728 
729 	mutex_lock(&rdev->ring_lock);
730 	ring_obj = ring->ring_obj;
731 	ring->ready = false;
732 	ring->ring = NULL;
733 	ring->ring_obj = NULL;
734 	mutex_unlock(&rdev->ring_lock);
735 
736 	if (ring_obj) {
737 		r = radeon_bo_reserve(ring_obj, false);
738 		if (likely(r == 0)) {
739 			radeon_bo_kunmap(ring_obj);
740 			radeon_bo_unpin(ring_obj);
741 			radeon_bo_unreserve(ring_obj);
742 		}
743 		radeon_bo_unref(&ring_obj);
744 	}
745 }
746 
747 /*
748  * Debugfs info
749  */
750 #if defined(CONFIG_DEBUG_FS)
751 
752 static int radeon_debugfs_ring_info(struct seq_file *m, void *data)
753 {
754 	struct drm_info_node *node = (struct drm_info_node *) m->private;
755 	struct drm_device *dev = node->minor->dev;
756 	struct radeon_device *rdev = dev->dev_private;
757 	int ridx = *(int*)node->info_ent->data;
758 	struct radeon_ring *ring = &rdev->ring[ridx];
759 
760 	uint32_t rptr, wptr, rptr_next;
761 	unsigned count, i, j;
762 
763 	radeon_ring_free_size(rdev, ring);
764 	count = (ring->ring_size / 4) - ring->ring_free_dw;
765 
766 	wptr = radeon_ring_get_wptr(rdev, ring);
767 	seq_printf(m, "wptr: 0x%08x [%5d]\n",
768 		   wptr, wptr);
769 
770 	rptr = radeon_ring_get_rptr(rdev, ring);
771 	seq_printf(m, "rptr: 0x%08x [%5d]\n",
772 		   rptr, rptr);
773 
774 	if (ring->rptr_save_reg) {
775 		rptr_next = RREG32(ring->rptr_save_reg);
776 		seq_printf(m, "rptr next(0x%04x): 0x%08x [%5d]\n",
777 			   ring->rptr_save_reg, rptr_next, rptr_next);
778 	} else
779 		rptr_next = ~0;
780 
781 	seq_printf(m, "driver's copy of the wptr: 0x%08x [%5d]\n",
782 		   ring->wptr, ring->wptr);
783 	seq_printf(m, "driver's copy of the rptr: 0x%08x [%5d]\n",
784 		   ring->rptr, ring->rptr);
785 	seq_printf(m, "last semaphore signal addr : 0x%016llx\n",
786 		   ring->last_semaphore_signal_addr);
787 	seq_printf(m, "last semaphore wait addr   : 0x%016llx\n",
788 		   ring->last_semaphore_wait_addr);
789 	seq_printf(m, "%u free dwords in ring\n", ring->ring_free_dw);
790 	seq_printf(m, "%u dwords in ring\n", count);
791 
792 	if (!ring->ready)
793 		return 0;
794 
795 	/* print 8 dw before current rptr as often it's the last executed
796 	 * packet that is the root issue
797 	 */
798 	i = (rptr + ring->ptr_mask + 1 - 32) & ring->ptr_mask;
799 	for (j = 0; j <= (count + 32); j++) {
800 		seq_printf(m, "r[%5d]=0x%08x", i, ring->ring[i]);
801 		if (rptr == i)
802 			seq_puts(m, " *");
803 		if (rptr_next == i)
804 			seq_puts(m, " #");
805 		seq_puts(m, "\n");
806 		i = (i + 1) & ring->ptr_mask;
807 	}
808 	return 0;
809 }
810 
811 static int radeon_gfx_index = RADEON_RING_TYPE_GFX_INDEX;
812 static int cayman_cp1_index = CAYMAN_RING_TYPE_CP1_INDEX;
813 static int cayman_cp2_index = CAYMAN_RING_TYPE_CP2_INDEX;
814 static int radeon_dma1_index = R600_RING_TYPE_DMA_INDEX;
815 static int radeon_dma2_index = CAYMAN_RING_TYPE_DMA1_INDEX;
816 static int r600_uvd_index = R600_RING_TYPE_UVD_INDEX;
817 
818 static struct drm_info_list radeon_debugfs_ring_info_list[] = {
819 	{"radeon_ring_gfx", radeon_debugfs_ring_info, 0, &radeon_gfx_index},
820 	{"radeon_ring_cp1", radeon_debugfs_ring_info, 0, &cayman_cp1_index},
821 	{"radeon_ring_cp2", radeon_debugfs_ring_info, 0, &cayman_cp2_index},
822 	{"radeon_ring_dma1", radeon_debugfs_ring_info, 0, &radeon_dma1_index},
823 	{"radeon_ring_dma2", radeon_debugfs_ring_info, 0, &radeon_dma2_index},
824 	{"radeon_ring_uvd", radeon_debugfs_ring_info, 0, &r600_uvd_index},
825 };
826 
827 static int radeon_debugfs_sa_info(struct seq_file *m, void *data)
828 {
829 	struct drm_info_node *node = (struct drm_info_node *) m->private;
830 	struct drm_device *dev = node->minor->dev;
831 	struct radeon_device *rdev = dev->dev_private;
832 
833 	radeon_sa_bo_dump_debug_info(&rdev->ring_tmp_bo, m);
834 
835 	return 0;
836 
837 }
838 
839 static struct drm_info_list radeon_debugfs_sa_list[] = {
840         {"radeon_sa_info", &radeon_debugfs_sa_info, 0, NULL},
841 };
842 
843 #endif
844 
845 static int radeon_debugfs_ring_init(struct radeon_device *rdev, struct radeon_ring *ring)
846 {
847 #if defined(CONFIG_DEBUG_FS)
848 	unsigned i;
849 	for (i = 0; i < ARRAY_SIZE(radeon_debugfs_ring_info_list); ++i) {
850 		struct drm_info_list *info = &radeon_debugfs_ring_info_list[i];
851 		int ridx = *(int*)radeon_debugfs_ring_info_list[i].data;
852 		unsigned r;
853 
854 		if (&rdev->ring[ridx] != ring)
855 			continue;
856 
857 		r = radeon_debugfs_add_files(rdev, info, 1);
858 		if (r)
859 			return r;
860 	}
861 #endif
862 	return 0;
863 }
864 
865 static int radeon_debugfs_sa_init(struct radeon_device *rdev)
866 {
867 #if defined(CONFIG_DEBUG_FS)
868 	return radeon_debugfs_add_files(rdev, radeon_debugfs_sa_list, 1);
869 #else
870 	return 0;
871 #endif
872 }
873