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/amdgpu_drm.h>
33 #include "amdgpu.h"
34 #include "atom.h"
35 
36 /*
37  * Rings
38  * Most engines on the GPU are fed via ring buffers.  Ring
39  * buffers are areas of GPU accessible memory that the host
40  * writes commands into and the GPU reads commands out of.
41  * There is a rptr (read pointer) that determines where the
42  * GPU is currently reading, and a wptr (write pointer)
43  * which determines where the host has written.  When the
44  * pointers are equal, the ring is idle.  When the host
45  * writes commands to the ring buffer, it increments the
46  * wptr.  The GPU then starts fetching commands and executes
47  * them until the pointers are equal again.
48  */
49 static int amdgpu_debugfs_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring);
50 
51 /**
52  * amdgpu_ring_alloc - allocate space on the ring buffer
53  *
54  * @adev: amdgpu_device pointer
55  * @ring: amdgpu_ring structure holding ring information
56  * @ndw: number of dwords to allocate in the ring buffer
57  *
58  * Allocate @ndw dwords in the ring buffer (all asics).
59  * Returns 0 on success, error on failure.
60  */
61 int amdgpu_ring_alloc(struct amdgpu_ring *ring, unsigned ndw)
62 {
63 	/* Align requested size with padding so unlock_commit can
64 	 * pad safely */
65 	ndw = (ndw + ring->align_mask) & ~ring->align_mask;
66 
67 	/* Make sure we aren't trying to allocate more space
68 	 * than the maximum for one submission
69 	 */
70 	if (WARN_ON_ONCE(ndw > ring->max_dw))
71 		return -ENOMEM;
72 
73 	ring->count_dw = ndw;
74 	ring->wptr_old = ring->wptr;
75 	return 0;
76 }
77 
78 /** amdgpu_ring_insert_nop - insert NOP packets
79  *
80  * @ring: amdgpu_ring structure holding ring information
81  * @count: the number of NOP packets to insert
82  *
83  * This is the generic insert_nop function for rings except SDMA
84  */
85 void amdgpu_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count)
86 {
87 	int i;
88 
89 	for (i = 0; i < count; i++)
90 		amdgpu_ring_write(ring, ring->nop);
91 }
92 
93 /** amdgpu_ring_generic_pad_ib - pad IB with NOP packets
94  *
95  * @ring: amdgpu_ring structure holding ring information
96  * @ib: IB to add NOP packets to
97  *
98  * This is the generic pad_ib function for rings except SDMA
99  */
100 void amdgpu_ring_generic_pad_ib(struct amdgpu_ring *ring, struct amdgpu_ib *ib)
101 {
102 	while (ib->length_dw & ring->align_mask)
103 		ib->ptr[ib->length_dw++] = ring->nop;
104 }
105 
106 /**
107  * amdgpu_ring_commit - tell the GPU to execute the new
108  * commands on the ring buffer
109  *
110  * @adev: amdgpu_device pointer
111  * @ring: amdgpu_ring structure holding ring information
112  *
113  * Update the wptr (write pointer) to tell the GPU to
114  * execute new commands on the ring buffer (all asics).
115  */
116 void amdgpu_ring_commit(struct amdgpu_ring *ring)
117 {
118 	uint32_t count;
119 
120 	/* We pad to match fetch size */
121 	count = ring->align_mask + 1 - (ring->wptr & ring->align_mask);
122 	count %= ring->align_mask + 1;
123 	ring->funcs->insert_nop(ring, count);
124 
125 	mb();
126 	amdgpu_ring_set_wptr(ring);
127 }
128 
129 /**
130  * amdgpu_ring_undo - reset the wptr
131  *
132  * @ring: amdgpu_ring structure holding ring information
133  *
134  * Reset the driver's copy of the wptr (all asics).
135  */
136 void amdgpu_ring_undo(struct amdgpu_ring *ring)
137 {
138 	ring->wptr = ring->wptr_old;
139 }
140 
141 /**
142  * amdgpu_ring_backup - Back up the content of a ring
143  *
144  * @ring: the ring we want to back up
145  *
146  * Saves all unprocessed commits from a ring, returns the number of dwords saved.
147  */
148 unsigned amdgpu_ring_backup(struct amdgpu_ring *ring,
149 			    uint32_t **data)
150 {
151 	unsigned size, ptr, i;
152 
153 	*data = NULL;
154 
155 	if (ring->ring_obj == NULL)
156 		return 0;
157 
158 	/* it doesn't make sense to save anything if all fences are signaled */
159 	if (!amdgpu_fence_count_emitted(ring))
160 		return 0;
161 
162 	ptr = le32_to_cpu(*ring->next_rptr_cpu_addr);
163 
164 	size = ring->wptr + (ring->ring_size / 4);
165 	size -= ptr;
166 	size &= ring->ptr_mask;
167 	if (size == 0)
168 		return 0;
169 
170 	/* and then save the content of the ring */
171 	*data = kmalloc_array(size, sizeof(uint32_t), GFP_KERNEL);
172 	if (!*data)
173 		return 0;
174 	for (i = 0; i < size; ++i) {
175 		(*data)[i] = ring->ring[ptr++];
176 		ptr &= ring->ptr_mask;
177 	}
178 
179 	return size;
180 }
181 
182 /**
183  * amdgpu_ring_restore - append saved commands to the ring again
184  *
185  * @ring: ring to append commands to
186  * @size: number of dwords we want to write
187  * @data: saved commands
188  *
189  * Allocates space on the ring and restore the previously saved commands.
190  */
191 int amdgpu_ring_restore(struct amdgpu_ring *ring,
192 			unsigned size, uint32_t *data)
193 {
194 	int i, r;
195 
196 	if (!size || !data)
197 		return 0;
198 
199 	/* restore the saved ring content */
200 	r = amdgpu_ring_alloc(ring, size);
201 	if (r)
202 		return r;
203 
204 	for (i = 0; i < size; ++i) {
205 		amdgpu_ring_write(ring, data[i]);
206 	}
207 
208 	amdgpu_ring_commit(ring);
209 	kfree(data);
210 	return 0;
211 }
212 
213 /**
214  * amdgpu_ring_init - init driver ring struct.
215  *
216  * @adev: amdgpu_device pointer
217  * @ring: amdgpu_ring structure holding ring information
218  * @ring_size: size of the ring
219  * @nop: nop packet for this ring
220  *
221  * Initialize the driver information for the selected ring (all asics).
222  * Returns 0 on success, error on failure.
223  */
224 int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
225 		     unsigned ring_size, u32 nop, u32 align_mask,
226 		     struct amdgpu_irq_src *irq_src, unsigned irq_type,
227 		     enum amdgpu_ring_type ring_type)
228 {
229 	u32 rb_bufsz;
230 	int r;
231 
232 	if (ring->adev == NULL) {
233 		if (adev->num_rings >= AMDGPU_MAX_RINGS)
234 			return -EINVAL;
235 
236 		ring->adev = adev;
237 		ring->idx = adev->num_rings++;
238 		adev->rings[ring->idx] = ring;
239 		r = amdgpu_fence_driver_init_ring(ring,
240 			amdgpu_sched_hw_submission);
241 		if (r)
242 			return r;
243 	}
244 
245 	r = amdgpu_wb_get(adev, &ring->rptr_offs);
246 	if (r) {
247 		dev_err(adev->dev, "(%d) ring rptr_offs wb alloc failed\n", r);
248 		return r;
249 	}
250 
251 	r = amdgpu_wb_get(adev, &ring->wptr_offs);
252 	if (r) {
253 		dev_err(adev->dev, "(%d) ring wptr_offs wb alloc failed\n", r);
254 		return r;
255 	}
256 
257 	r = amdgpu_wb_get(adev, &ring->fence_offs);
258 	if (r) {
259 		dev_err(adev->dev, "(%d) ring fence_offs wb alloc failed\n", r);
260 		return r;
261 	}
262 
263 	r = amdgpu_wb_get(adev, &ring->next_rptr_offs);
264 	if (r) {
265 		dev_err(adev->dev, "(%d) ring next_rptr wb alloc failed\n", r);
266 		return r;
267 	}
268 	ring->next_rptr_gpu_addr = adev->wb.gpu_addr + (ring->next_rptr_offs * 4);
269 	ring->next_rptr_cpu_addr = &adev->wb.wb[ring->next_rptr_offs];
270 	spin_lock_init(&ring->fence_lock);
271 	r = amdgpu_fence_driver_start_ring(ring, irq_src, irq_type);
272 	if (r) {
273 		dev_err(adev->dev, "failed initializing fences (%d).\n", r);
274 		return r;
275 	}
276 
277 	/* Align ring size */
278 	rb_bufsz = order_base_2(ring_size / 8);
279 	ring_size = (1 << (rb_bufsz + 1)) * 4;
280 	ring->ring_size = ring_size;
281 	ring->align_mask = align_mask;
282 	ring->nop = nop;
283 	ring->type = ring_type;
284 
285 	/* Allocate ring buffer */
286 	if (ring->ring_obj == NULL) {
287 		r = amdgpu_bo_create(adev, ring->ring_size, PAGE_SIZE, true,
288 				     AMDGPU_GEM_DOMAIN_GTT, 0,
289 				     NULL, NULL, &ring->ring_obj);
290 		if (r) {
291 			dev_err(adev->dev, "(%d) ring create failed\n", r);
292 			return r;
293 		}
294 		r = amdgpu_bo_reserve(ring->ring_obj, false);
295 		if (unlikely(r != 0))
296 			return r;
297 		r = amdgpu_bo_pin(ring->ring_obj, AMDGPU_GEM_DOMAIN_GTT,
298 					&ring->gpu_addr);
299 		if (r) {
300 			amdgpu_bo_unreserve(ring->ring_obj);
301 			dev_err(adev->dev, "(%d) ring pin failed\n", r);
302 			return r;
303 		}
304 		r = amdgpu_bo_kmap(ring->ring_obj,
305 				       (void **)&ring->ring);
306 		amdgpu_bo_unreserve(ring->ring_obj);
307 		if (r) {
308 			dev_err(adev->dev, "(%d) ring map failed\n", r);
309 			return r;
310 		}
311 	}
312 	ring->ptr_mask = (ring->ring_size / 4) - 1;
313 	ring->max_dw = DIV_ROUND_UP(ring->ring_size / 4,
314 				    amdgpu_sched_hw_submission);
315 
316 	if (amdgpu_debugfs_ring_init(adev, ring)) {
317 		DRM_ERROR("Failed to register debugfs file for rings !\n");
318 	}
319 	return 0;
320 }
321 
322 /**
323  * amdgpu_ring_fini - tear down the driver ring struct.
324  *
325  * @adev: amdgpu_device pointer
326  * @ring: amdgpu_ring structure holding ring information
327  *
328  * Tear down the driver information for the selected ring (all asics).
329  */
330 void amdgpu_ring_fini(struct amdgpu_ring *ring)
331 {
332 	int r;
333 	struct amdgpu_bo *ring_obj;
334 
335 	ring_obj = ring->ring_obj;
336 	ring->ready = false;
337 	ring->ring = NULL;
338 	ring->ring_obj = NULL;
339 
340 	amdgpu_wb_free(ring->adev, ring->fence_offs);
341 	amdgpu_wb_free(ring->adev, ring->rptr_offs);
342 	amdgpu_wb_free(ring->adev, ring->wptr_offs);
343 	amdgpu_wb_free(ring->adev, ring->next_rptr_offs);
344 
345 	if (ring_obj) {
346 		r = amdgpu_bo_reserve(ring_obj, false);
347 		if (likely(r == 0)) {
348 			amdgpu_bo_kunmap(ring_obj);
349 			amdgpu_bo_unpin(ring_obj);
350 			amdgpu_bo_unreserve(ring_obj);
351 		}
352 		amdgpu_bo_unref(&ring_obj);
353 	}
354 }
355 
356 /*
357  * Debugfs info
358  */
359 #if defined(CONFIG_DEBUG_FS)
360 
361 static int amdgpu_debugfs_ring_info(struct seq_file *m, void *data)
362 {
363 	struct drm_info_node *node = (struct drm_info_node *) m->private;
364 	struct drm_device *dev = node->minor->dev;
365 	struct amdgpu_device *adev = dev->dev_private;
366 	int roffset = *(int*)node->info_ent->data;
367 	struct amdgpu_ring *ring = (void *)(((uint8_t*)adev) + roffset);
368 
369 	uint32_t rptr, wptr, rptr_next;
370 	unsigned i;
371 
372 	wptr = amdgpu_ring_get_wptr(ring);
373 	seq_printf(m, "wptr: 0x%08x [%5d]\n", wptr, wptr);
374 
375 	rptr = amdgpu_ring_get_rptr(ring);
376 	rptr_next = le32_to_cpu(*ring->next_rptr_cpu_addr);
377 
378 	seq_printf(m, "rptr: 0x%08x [%5d]\n", rptr, rptr);
379 
380 	seq_printf(m, "driver's copy of the wptr: 0x%08x [%5d]\n",
381 		   ring->wptr, ring->wptr);
382 
383 	if (!ring->ready)
384 		return 0;
385 
386 	/* print 8 dw before current rptr as often it's the last executed
387 	 * packet that is the root issue
388 	 */
389 	i = (rptr + ring->ptr_mask + 1 - 32) & ring->ptr_mask;
390 	while (i != rptr) {
391 		seq_printf(m, "r[%5d]=0x%08x", i, ring->ring[i]);
392 		if (i == rptr)
393 			seq_puts(m, " *");
394 		if (i == rptr_next)
395 			seq_puts(m, " #");
396 		seq_puts(m, "\n");
397 		i = (i + 1) & ring->ptr_mask;
398 	}
399 	while (i != wptr) {
400 		seq_printf(m, "r[%5d]=0x%08x", i, ring->ring[i]);
401 		if (i == rptr)
402 			seq_puts(m, " *");
403 		if (i == rptr_next)
404 			seq_puts(m, " #");
405 		seq_puts(m, "\n");
406 		i = (i + 1) & ring->ptr_mask;
407 	}
408 	return 0;
409 }
410 
411 /* TODO: clean this up !*/
412 static int amdgpu_gfx_index = offsetof(struct amdgpu_device, gfx.gfx_ring[0]);
413 static int cayman_cp1_index = offsetof(struct amdgpu_device, gfx.compute_ring[0]);
414 static int cayman_cp2_index = offsetof(struct amdgpu_device, gfx.compute_ring[1]);
415 static int amdgpu_dma1_index = offsetof(struct amdgpu_device, sdma.instance[0].ring);
416 static int amdgpu_dma2_index = offsetof(struct amdgpu_device, sdma.instance[1].ring);
417 static int r600_uvd_index = offsetof(struct amdgpu_device, uvd.ring);
418 static int si_vce1_index = offsetof(struct amdgpu_device, vce.ring[0]);
419 static int si_vce2_index = offsetof(struct amdgpu_device, vce.ring[1]);
420 
421 static struct drm_info_list amdgpu_debugfs_ring_info_list[] = {
422 	{"amdgpu_ring_gfx", amdgpu_debugfs_ring_info, 0, &amdgpu_gfx_index},
423 	{"amdgpu_ring_cp1", amdgpu_debugfs_ring_info, 0, &cayman_cp1_index},
424 	{"amdgpu_ring_cp2", amdgpu_debugfs_ring_info, 0, &cayman_cp2_index},
425 	{"amdgpu_ring_dma1", amdgpu_debugfs_ring_info, 0, &amdgpu_dma1_index},
426 	{"amdgpu_ring_dma2", amdgpu_debugfs_ring_info, 0, &amdgpu_dma2_index},
427 	{"amdgpu_ring_uvd", amdgpu_debugfs_ring_info, 0, &r600_uvd_index},
428 	{"amdgpu_ring_vce1", amdgpu_debugfs_ring_info, 0, &si_vce1_index},
429 	{"amdgpu_ring_vce2", amdgpu_debugfs_ring_info, 0, &si_vce2_index},
430 };
431 
432 #endif
433 
434 static int amdgpu_debugfs_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring)
435 {
436 #if defined(CONFIG_DEBUG_FS)
437 	unsigned i;
438 	for (i = 0; i < ARRAY_SIZE(amdgpu_debugfs_ring_info_list); ++i) {
439 		struct drm_info_list *info = &amdgpu_debugfs_ring_info_list[i];
440 		int roffset = *(int*)amdgpu_debugfs_ring_info_list[i].data;
441 		struct amdgpu_ring *other = (void *)(((uint8_t*)adev) + roffset);
442 		unsigned r;
443 
444 		if (other != ring)
445 			continue;
446 
447 		r = amdgpu_debugfs_add_files(adev, info, 1);
448 		if (r)
449 			return r;
450 	}
451 #endif
452 	return 0;
453 }
454