2 * Copyright 2008 Advanced Micro Devices, Inc.
3 * Copyright 2008 Red Hat Inc.
4 * Copyright 2009 Jerome Glisse.
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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.
24 * Authors: Dave Airlie
29 #include <linux/seq_file.h>
30 #include <linux/slab.h>
31 #include <linux/debugfs.h>
33 #include <drm/amdgpu_drm.h>
39 * Most engines on the GPU are fed via ring buffers. Ring
40 * buffers are areas of GPU accessible memory that the host
41 * writes commands into and the GPU reads commands out of.
42 * There is a rptr (read pointer) that determines where the
43 * GPU is currently reading, and a wptr (write pointer)
44 * which determines where the host has written. When the
45 * pointers are equal, the ring is idle. When the host
46 * writes commands to the ring buffer, it increments the
47 * wptr. The GPU then starts fetching commands and executes
48 * them until the pointers are equal again.
50 static int amdgpu_debugfs_ring_init(struct amdgpu_device
*adev
,
51 struct amdgpu_ring
*ring
);
52 static void amdgpu_debugfs_ring_fini(struct amdgpu_ring
*ring
);
55 * amdgpu_ring_alloc - allocate space on the ring buffer
57 * @adev: amdgpu_device pointer
58 * @ring: amdgpu_ring structure holding ring information
59 * @ndw: number of dwords to allocate in the ring buffer
61 * Allocate @ndw dwords in the ring buffer (all asics).
62 * Returns 0 on success, error on failure.
64 int amdgpu_ring_alloc(struct amdgpu_ring
*ring
, unsigned ndw
)
66 /* Align requested size with padding so unlock_commit can
68 ndw
= (ndw
+ ring
->align_mask
) & ~ring
->align_mask
;
70 /* Make sure we aren't trying to allocate more space
71 * than the maximum for one submission
73 if (WARN_ON_ONCE(ndw
> ring
->max_dw
))
77 ring
->wptr_old
= ring
->wptr
;
79 if (ring
->funcs
->begin_use
)
80 ring
->funcs
->begin_use(ring
);
85 /** amdgpu_ring_insert_nop - insert NOP packets
87 * @ring: amdgpu_ring structure holding ring information
88 * @count: the number of NOP packets to insert
90 * This is the generic insert_nop function for rings except SDMA
92 void amdgpu_ring_insert_nop(struct amdgpu_ring
*ring
, uint32_t count
)
96 for (i
= 0; i
< count
; i
++)
97 amdgpu_ring_write(ring
, ring
->nop
);
100 /** amdgpu_ring_generic_pad_ib - pad IB with NOP packets
102 * @ring: amdgpu_ring structure holding ring information
103 * @ib: IB to add NOP packets to
105 * This is the generic pad_ib function for rings except SDMA
107 void amdgpu_ring_generic_pad_ib(struct amdgpu_ring
*ring
, struct amdgpu_ib
*ib
)
109 while (ib
->length_dw
& ring
->align_mask
)
110 ib
->ptr
[ib
->length_dw
++] = ring
->nop
;
114 * amdgpu_ring_commit - tell the GPU to execute the new
115 * commands on the ring buffer
117 * @adev: amdgpu_device pointer
118 * @ring: amdgpu_ring structure holding ring information
120 * Update the wptr (write pointer) to tell the GPU to
121 * execute new commands on the ring buffer (all asics).
123 void amdgpu_ring_commit(struct amdgpu_ring
*ring
)
127 /* We pad to match fetch size */
128 count
= ring
->align_mask
+ 1 - (ring
->wptr
& ring
->align_mask
);
129 count
%= ring
->align_mask
+ 1;
130 ring
->funcs
->insert_nop(ring
, count
);
133 amdgpu_ring_set_wptr(ring
);
135 if (ring
->funcs
->end_use
)
136 ring
->funcs
->end_use(ring
);
140 * amdgpu_ring_undo - reset the wptr
142 * @ring: amdgpu_ring structure holding ring information
144 * Reset the driver's copy of the wptr (all asics).
146 void amdgpu_ring_undo(struct amdgpu_ring
*ring
)
148 ring
->wptr
= ring
->wptr_old
;
150 if (ring
->funcs
->end_use
)
151 ring
->funcs
->end_use(ring
);
155 * amdgpu_ring_init - init driver ring struct.
157 * @adev: amdgpu_device pointer
158 * @ring: amdgpu_ring structure holding ring information
159 * @max_ndw: maximum number of dw for ring alloc
160 * @nop: nop packet for this ring
162 * Initialize the driver information for the selected ring (all asics).
163 * Returns 0 on success, error on failure.
165 int amdgpu_ring_init(struct amdgpu_device
*adev
, struct amdgpu_ring
*ring
,
166 unsigned max_dw
, u32 nop
, u32 align_mask
,
167 struct amdgpu_irq_src
*irq_src
, unsigned irq_type
,
168 enum amdgpu_ring_type ring_type
)
172 if (ring
->adev
== NULL
) {
173 if (adev
->num_rings
>= AMDGPU_MAX_RINGS
)
177 ring
->idx
= adev
->num_rings
++;
178 adev
->rings
[ring
->idx
] = ring
;
179 r
= amdgpu_fence_driver_init_ring(ring
,
180 amdgpu_sched_hw_submission
);
185 r
= amdgpu_wb_get(adev
, &ring
->rptr_offs
);
187 dev_err(adev
->dev
, "(%d) ring rptr_offs wb alloc failed\n", r
);
191 r
= amdgpu_wb_get(adev
, &ring
->wptr_offs
);
193 dev_err(adev
->dev
, "(%d) ring wptr_offs wb alloc failed\n", r
);
197 r
= amdgpu_wb_get(adev
, &ring
->fence_offs
);
199 dev_err(adev
->dev
, "(%d) ring fence_offs wb alloc failed\n", r
);
203 r
= amdgpu_wb_get(adev
, &ring
->cond_exe_offs
);
205 dev_err(adev
->dev
, "(%d) ring cond_exec_polling wb alloc failed\n", r
);
208 ring
->cond_exe_gpu_addr
= adev
->wb
.gpu_addr
+ (ring
->cond_exe_offs
* 4);
209 ring
->cond_exe_cpu_addr
= &adev
->wb
.wb
[ring
->cond_exe_offs
];
211 r
= amdgpu_fence_driver_start_ring(ring
, irq_src
, irq_type
);
213 dev_err(adev
->dev
, "failed initializing fences (%d).\n", r
);
217 ring
->ring_size
= roundup_pow_of_two(max_dw
* 4 *
218 amdgpu_sched_hw_submission
);
219 ring
->align_mask
= align_mask
;
221 ring
->type
= ring_type
;
223 /* Allocate ring buffer */
224 if (ring
->ring_obj
== NULL
) {
225 r
= amdgpu_bo_create(adev
, ring
->ring_size
, PAGE_SIZE
, true,
226 AMDGPU_GEM_DOMAIN_GTT
, 0,
227 NULL
, NULL
, &ring
->ring_obj
);
229 dev_err(adev
->dev
, "(%d) ring create failed\n", r
);
232 r
= amdgpu_bo_reserve(ring
->ring_obj
, false);
233 if (unlikely(r
!= 0))
235 r
= amdgpu_bo_pin(ring
->ring_obj
, AMDGPU_GEM_DOMAIN_GTT
,
238 amdgpu_bo_unreserve(ring
->ring_obj
);
239 dev_err(adev
->dev
, "(%d) ring pin failed\n", r
);
242 r
= amdgpu_bo_kmap(ring
->ring_obj
,
243 (void **)&ring
->ring
);
245 memset((void *)ring
->ring
, 0, ring
->ring_size
);
247 amdgpu_bo_unreserve(ring
->ring_obj
);
249 dev_err(adev
->dev
, "(%d) ring map failed\n", r
);
253 ring
->ptr_mask
= (ring
->ring_size
/ 4) - 1;
254 ring
->max_dw
= max_dw
;
256 if (amdgpu_debugfs_ring_init(adev
, ring
)) {
257 DRM_ERROR("Failed to register debugfs file for rings !\n");
263 * amdgpu_ring_fini - tear down the driver ring struct.
265 * @adev: amdgpu_device pointer
266 * @ring: amdgpu_ring structure holding ring information
268 * Tear down the driver information for the selected ring (all asics).
270 void amdgpu_ring_fini(struct amdgpu_ring
*ring
)
273 struct amdgpu_bo
*ring_obj
;
275 ring_obj
= ring
->ring_obj
;
278 ring
->ring_obj
= NULL
;
280 amdgpu_wb_free(ring
->adev
, ring
->cond_exe_offs
);
281 amdgpu_wb_free(ring
->adev
, ring
->fence_offs
);
282 amdgpu_wb_free(ring
->adev
, ring
->rptr_offs
);
283 amdgpu_wb_free(ring
->adev
, ring
->wptr_offs
);
286 r
= amdgpu_bo_reserve(ring_obj
, false);
287 if (likely(r
== 0)) {
288 amdgpu_bo_kunmap(ring_obj
);
289 amdgpu_bo_unpin(ring_obj
);
290 amdgpu_bo_unreserve(ring_obj
);
292 amdgpu_bo_unref(&ring_obj
);
294 amdgpu_debugfs_ring_fini(ring
);
300 #if defined(CONFIG_DEBUG_FS)
302 /* Layout of file is 12 bytes consisting of
305 * - driver's copy of wptr
307 * followed by n-words of ring data
309 static ssize_t
amdgpu_debugfs_ring_read(struct file
*f
, char __user
*buf
,
310 size_t size
, loff_t
*pos
)
312 struct amdgpu_ring
*ring
= (struct amdgpu_ring
*)f
->f_inode
->i_private
;
314 uint32_t value
, result
, early
[3];
316 if (*pos
& 3 || size
& 3)
322 early
[0] = amdgpu_ring_get_rptr(ring
);
323 early
[1] = amdgpu_ring_get_wptr(ring
);
324 early
[2] = ring
->wptr
;
325 for (i
= *pos
/ 4; i
< 3 && size
; i
++) {
326 r
= put_user(early
[i
], (uint32_t *)buf
);
337 if (*pos
>= (ring
->ring_size
+ 12))
340 value
= ring
->ring
[(*pos
- 12)/4];
341 r
= put_user(value
, (uint32_t*)buf
);
353 static const struct file_operations amdgpu_debugfs_ring_fops
= {
354 .owner
= THIS_MODULE
,
355 .read
= amdgpu_debugfs_ring_read
,
356 .llseek
= default_llseek
361 static int amdgpu_debugfs_ring_init(struct amdgpu_device
*adev
,
362 struct amdgpu_ring
*ring
)
364 #if defined(CONFIG_DEBUG_FS)
365 struct drm_minor
*minor
= adev
->ddev
->primary
;
366 struct dentry
*ent
, *root
= minor
->debugfs_root
;
369 sprintf(name
, "amdgpu_ring_%s", ring
->name
);
371 ent
= debugfs_create_file(name
,
372 S_IFREG
| S_IRUGO
, root
,
373 ring
, &amdgpu_debugfs_ring_fops
);
377 i_size_write(ent
->d_inode
, ring
->ring_size
+ 12);
383 static void amdgpu_debugfs_ring_fini(struct amdgpu_ring
*ring
)
385 #if defined(CONFIG_DEBUG_FS)
386 debugfs_remove(ring
->ent
);