1 /* $NetBSD: radeon_sync.c,v 1.3 2021/12/18 23:45:43 riastradh Exp $ */
2
3 /*
4 * Copyright 2014 Advanced Micro Devices, Inc.
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
21 * USE OR OTHER DEALINGS IN THE SOFTWARE.
22 *
23 * The above copyright notice and this permission notice (including the
24 * next paragraph) shall be included in all copies or substantial portions
25 * of the Software.
26 *
27 */
28 /*
29 * Authors:
30 * Christian König <christian.koenig@amd.com>
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: radeon_sync.c,v 1.3 2021/12/18 23:45:43 riastradh Exp $");
35
36 #include "radeon.h"
37 #include "radeon_trace.h"
38
39 /**
40 * radeon_sync_create - zero init sync object
41 *
42 * @sync: sync object to initialize
43 *
44 * Just clear the sync object for now.
45 */
radeon_sync_create(struct radeon_sync * sync)46 void radeon_sync_create(struct radeon_sync *sync)
47 {
48 unsigned i;
49
50 for (i = 0; i < RADEON_NUM_SYNCS; ++i)
51 sync->semaphores[i] = NULL;
52
53 for (i = 0; i < RADEON_NUM_RINGS; ++i)
54 sync->sync_to[i] = NULL;
55
56 sync->last_vm_update = NULL;
57 }
58
59 /**
60 * radeon_sync_fence - use the semaphore to sync to a fence
61 *
62 * @sync: sync object to add fence to
63 * @fence: fence to sync to
64 *
65 * Sync to the fence using the semaphore objects
66 */
radeon_sync_fence(struct radeon_sync * sync,struct radeon_fence * fence)67 void radeon_sync_fence(struct radeon_sync *sync,
68 struct radeon_fence *fence)
69 {
70 struct radeon_fence *other;
71
72 if (!fence)
73 return;
74
75 other = sync->sync_to[fence->ring];
76 sync->sync_to[fence->ring] = radeon_fence_later(fence, other);
77
78 if (fence->is_vm_update) {
79 other = sync->last_vm_update;
80 sync->last_vm_update = radeon_fence_later(fence, other);
81 }
82 }
83
84 /**
85 * radeon_sync_resv - use the semaphores to sync to a reservation object
86 *
87 * @sync: sync object to add fences from reservation object to
88 * @resv: reservation object with embedded fence
89 * @shared: true if we should only sync to the exclusive fence
90 *
91 * Sync to the fence using the semaphore objects
92 */
radeon_sync_resv(struct radeon_device * rdev,struct radeon_sync * sync,struct dma_resv * resv,bool shared)93 int radeon_sync_resv(struct radeon_device *rdev,
94 struct radeon_sync *sync,
95 struct dma_resv *resv,
96 bool shared)
97 {
98 struct dma_resv_list *flist;
99 struct dma_fence *f;
100 struct radeon_fence *fence;
101 unsigned i;
102 int r = 0;
103
104 /* always sync to the exclusive fence */
105 f = dma_resv_get_excl(resv);
106 fence = f ? to_radeon_fence(f) : NULL;
107 if (fence && fence->rdev == rdev)
108 radeon_sync_fence(sync, fence);
109 else if (f)
110 r = dma_fence_wait(f, true);
111
112 flist = dma_resv_get_list(resv);
113 if (shared || !flist || r)
114 return r;
115
116 for (i = 0; i < flist->shared_count; ++i) {
117 f = rcu_dereference_protected(flist->shared[i],
118 dma_resv_held(resv));
119 fence = to_radeon_fence(f);
120 if (fence && fence->rdev == rdev)
121 radeon_sync_fence(sync, fence);
122 else
123 r = dma_fence_wait(f, true);
124
125 if (r)
126 break;
127 }
128 return r;
129 }
130
131 /**
132 * radeon_sync_rings - sync ring to all registered fences
133 *
134 * @rdev: radeon_device pointer
135 * @sync: sync object to use
136 * @ring: ring that needs sync
137 *
138 * Ensure that all registered fences are signaled before letting
139 * the ring continue. The caller must hold the ring lock.
140 */
radeon_sync_rings(struct radeon_device * rdev,struct radeon_sync * sync,int ring)141 int radeon_sync_rings(struct radeon_device *rdev,
142 struct radeon_sync *sync,
143 int ring)
144 {
145 unsigned count = 0;
146 int i, r;
147
148 for (i = 0; i < RADEON_NUM_RINGS; ++i) {
149 struct radeon_fence *fence = sync->sync_to[i];
150 struct radeon_semaphore *semaphore;
151
152 /* check if we really need to sync */
153 if (!radeon_fence_need_sync(fence, ring))
154 continue;
155
156 /* prevent GPU deadlocks */
157 if (!rdev->ring[i].ready) {
158 dev_err(rdev->dev, "Syncing to a disabled ring!");
159 return -EINVAL;
160 }
161
162 if (count >= RADEON_NUM_SYNCS) {
163 /* not enough room, wait manually */
164 r = radeon_fence_wait(fence, false);
165 if (r)
166 return r;
167 continue;
168 }
169 r = radeon_semaphore_create(rdev, &semaphore);
170 if (r)
171 return r;
172
173 sync->semaphores[count++] = semaphore;
174
175 /* allocate enough space for sync command */
176 r = radeon_ring_alloc(rdev, &rdev->ring[i], 16);
177 if (r)
178 return r;
179
180 /* emit the signal semaphore */
181 if (!radeon_semaphore_emit_signal(rdev, i, semaphore)) {
182 /* signaling wasn't successful wait manually */
183 radeon_ring_undo(&rdev->ring[i]);
184 r = radeon_fence_wait(fence, false);
185 if (r)
186 return r;
187 continue;
188 }
189
190 /* we assume caller has already allocated space on waiters ring */
191 if (!radeon_semaphore_emit_wait(rdev, ring, semaphore)) {
192 /* waiting wasn't successful wait manually */
193 radeon_ring_undo(&rdev->ring[i]);
194 r = radeon_fence_wait(fence, false);
195 if (r)
196 return r;
197 continue;
198 }
199
200 radeon_ring_commit(rdev, &rdev->ring[i], false);
201 radeon_fence_note_sync(fence, ring);
202 }
203
204 return 0;
205 }
206
207 /**
208 * radeon_sync_free - free the sync object
209 *
210 * @rdev: radeon_device pointer
211 * @sync: sync object to use
212 * @fence: fence to use for the free
213 *
214 * Free the sync object by freeing all semaphores in it.
215 */
radeon_sync_free(struct radeon_device * rdev,struct radeon_sync * sync,struct radeon_fence * fence)216 void radeon_sync_free(struct radeon_device *rdev,
217 struct radeon_sync *sync,
218 struct radeon_fence *fence)
219 {
220 unsigned i;
221
222 for (i = 0; i < RADEON_NUM_SYNCS; ++i)
223 radeon_semaphore_free(rdev, &sync->semaphores[i], fence);
224 }
225