drivers/gpu/drm/radeon/radeon_sync.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   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  *    Christian König <christian.koenig@amd.com>
  29  */
  30
  31 #include "radeon.h"
  32 #include "radeon_trace.h"
  33
  34 /**
  35  * radeon_sync_create - zero init sync object
  36  *
  37  * @sync: sync object to initialize
  38  *
  39  * Just clear the sync object for now.
  40  */
  41 void radeon_sync_create(struct radeon_sync *sync)
  42 {
  43         unsigned i;
  44
  45         for (i = 0; i < RADEON_NUM_SYNCS; ++i)
  46                 sync->semaphores[i] = NULL;
  47
  48         for (i = 0; i < RADEON_NUM_RINGS; ++i)
  49                 sync->sync_to[i] = NULL;
  50
  51         sync->last_vm_update = NULL;
  52 }
  53
  54 /**
  55  * radeon_sync_fence - use the semaphore to sync to a fence
  56  *
  57  * @sync: sync object to add fence to
  58  * @fence: fence to sync to
  59  *
  60  * Sync to the fence using the semaphore objects
  61  */
  62 void radeon_sync_fence(struct radeon_sync *sync,
  63                        struct radeon_fence *fence)
  64 {
  65         struct radeon_fence *other;
  66
  67         if (!fence)
  68                 return;
  69
  70         other = sync->sync_to[fence->ring];
  71         sync->sync_to[fence->ring] = radeon_fence_later(fence, other);
  72
  73         if (fence->is_vm_update) {
  74                 other = sync->last_vm_update;
  75                 sync->last_vm_update = radeon_fence_later(fence, other);
  76         }
  77 }
  78
  79 /**
  80  * radeon_sync_resv - use the semaphores to sync to a reservation object
  81  *
  82  * @sync: sync object to add fences from reservation object to
  83  * @resv: reservation object with embedded fence
  84  * @shared: true if we should only sync to the exclusive fence
  85  *
  86  * Sync to the fence using the semaphore objects
  87  */
  88 int radeon_sync_resv(struct radeon_device *rdev,
  89                      struct radeon_sync *sync,
  90                      struct dma_resv *resv,
  91                      bool shared)
  92 {
  93         struct dma_resv_list *flist;
  94         struct dma_fence *f;
  95         struct radeon_fence *fence;
  96         unsigned i;
  97         int r = 0;
  98
  99         /* always sync to the exclusive fence */
 100         f = dma_resv_get_excl(resv);
 101         fence = f ? to_radeon_fence(f) : NULL;
 102         if (fence && fence->rdev == rdev)
 103                 radeon_sync_fence(sync, fence);
 104         else if (f)
 105                 r = dma_fence_wait(f, true);
 106
 107         flist = dma_resv_get_list(resv);
 108         if (shared || !flist || r)
 109                 return r;
 110
 111         for (i = 0; i < flist->shared_count; ++i) {
 112                 f = rcu_dereference_protected(flist->shared[i],
 113                                               dma_resv_held(resv));
 114                 fence = to_radeon_fence(f);
 115                 if (fence && fence->rdev == rdev)
 116                         radeon_sync_fence(sync, fence);
 117                 else
 118                         r = dma_fence_wait(f, true);
 119
 120                 if (r)
 121                         break;
 122         }
 123         return r;
 124 }
 125
 126 /**
 127  * radeon_sync_rings - sync ring to all registered fences
 128  *
 129  * @rdev: radeon_device pointer
 130  * @sync: sync object to use
 131  * @ring: ring that needs sync
 132  *
 133  * Ensure that all registered fences are signaled before letting
 134  * the ring continue. The caller must hold the ring lock.
 135  */
 136 int radeon_sync_rings(struct radeon_device *rdev,
 137                       struct radeon_sync *sync,
 138                       int ring)
 139 {
 140         unsigned count = 0;
 141         int i, r;
 142
 143         for (i = 0; i < RADEON_NUM_RINGS; ++i) {
 144                 struct radeon_fence *fence = sync->sync_to[i];
 145                 struct radeon_semaphore *semaphore;
 146
 147                 /* check if we really need to sync */
 148                 if (!radeon_fence_need_sync(fence, ring))
 149                         continue;
 150
 151                 /* prevent GPU deadlocks */
 152                 if (!rdev->ring[i].ready) {
 153                         dev_err(rdev->dev, "Syncing to a disabled ring!");
 154                         return -EINVAL;
 155                 }
 156
 157                 if (count >= RADEON_NUM_SYNCS) {
 158                         /* not enough room, wait manually */
 159                         r = radeon_fence_wait(fence, false);
 160                         if (r)
 161                                 return r;
 162                         continue;
 163                 }
 164                 r = radeon_semaphore_create(rdev, &semaphore);
 165                 if (r)
 166                         return r;
 167
 168                 sync->semaphores[count++] = semaphore;
 169
 170                 /* allocate enough space for sync command */
 171                 r = radeon_ring_alloc(rdev, &rdev->ring[i], 16);
 172                 if (r)
 173                         return r;
 174
 175                 /* emit the signal semaphore */
 176                 if (!radeon_semaphore_emit_signal(rdev, i, semaphore)) {
 177                         /* signaling wasn't successful wait manually */
 178                         radeon_ring_undo(&rdev->ring[i]);
 179                         r = radeon_fence_wait(fence, false);
 180                         if (r)
 181                                 return r;
 182                         continue;
 183                 }
 184
 185                 /* we assume caller has already allocated space on waiters ring */
 186                 if (!radeon_semaphore_emit_wait(rdev, ring, semaphore)) {
 187                         /* waiting wasn't successful wait manually */
 188                         radeon_ring_undo(&rdev->ring[i]);
 189                         r = radeon_fence_wait(fence, false);
 190                         if (r)
 191                                 return r;
 192                         continue;
 193                 }
 194
 195                 radeon_ring_commit(rdev, &rdev->ring[i], false);
 196                 radeon_fence_note_sync(fence, ring);
 197         }
 198
 199         return 0;
 200 }
 201
 202 /**
 203  * radeon_sync_free - free the sync object
 204  *
 205  * @rdev: radeon_device pointer
 206  * @sync: sync object to use
 207  * @fence: fence to use for the free
 208  *
 209  * Free the sync object by freeing all semaphores in it.
 210  */
 211 void radeon_sync_free(struct radeon_device *rdev,
 212                       struct radeon_sync *sync,
 213                       struct radeon_fence *fence)
 214 {
 215         unsigned i;
 216
 217         for (i = 0; i < RADEON_NUM_SYNCS; ++i)
 218                 radeon_semaphore_free(rdev, &sync->semaphores[i], fence);
 219 }