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 */
 41void 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 */
 62void 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 * @rdev: radeon_device pointer
 83 * @sync: sync object to add fences from reservation object to
 84 * @resv: reservation object with embedded fence
 85 * @shared: true if we should only sync to the exclusive fence
 86 *
 87 * Sync to the fence using the semaphore objects
 88 */
 89int radeon_sync_resv(struct radeon_device *rdev,
 90		     struct radeon_sync *sync,
 91		     struct dma_resv *resv,
 92		     bool shared)
 93{
 94	struct dma_resv_iter cursor;
 95	struct radeon_fence *fence;
 96	struct dma_fence *f;
 97	int r = 0;
 98
 99	dma_resv_for_each_fence(&cursor, resv, dma_resv_usage_rw(!shared), f) {
100		fence = to_radeon_fence(f);
101		if (fence && fence->rdev == rdev)
102			radeon_sync_fence(sync, fence);
103		else
104			r = dma_fence_wait(f, true);
105		if (r)
106			break;
107	}
108	return r;
109}
110
111/**
112 * radeon_sync_rings - sync ring to all registered fences
113 *
114 * @rdev: radeon_device pointer
115 * @sync: sync object to use
116 * @ring: ring that needs sync
117 *
118 * Ensure that all registered fences are signaled before letting
119 * the ring continue. The caller must hold the ring lock.
120 */
121int radeon_sync_rings(struct radeon_device *rdev,
122		      struct radeon_sync *sync,
123		      int ring)
124{
125	unsigned count = 0;
126	int i, r;
127
128	for (i = 0; i < RADEON_NUM_RINGS; ++i) {
129		struct radeon_fence *fence = sync->sync_to[i];
130		struct radeon_semaphore *semaphore;
131
132		/* check if we really need to sync */
133		if (!radeon_fence_need_sync(fence, ring))
134			continue;
135
136		/* prevent GPU deadlocks */
137		if (!rdev->ring[i].ready) {
138			dev_err(rdev->dev, "Syncing to a disabled ring!");
139			return -EINVAL;
140		}
141
142		if (count >= RADEON_NUM_SYNCS) {
143			/* not enough room, wait manually */
144			r = radeon_fence_wait(fence, false);
145			if (r)
146				return r;
147			continue;
148		}
149		r = radeon_semaphore_create(rdev, &semaphore);
150		if (r)
151			return r;
152
153		sync->semaphores[count++] = semaphore;
154
155		/* allocate enough space for sync command */
156		r = radeon_ring_alloc(rdev, &rdev->ring[i], 16);
157		if (r)
158			return r;
159
160		/* emit the signal semaphore */
161		if (!radeon_semaphore_emit_signal(rdev, i, semaphore)) {
162			/* signaling wasn't successful wait manually */
163			radeon_ring_undo(&rdev->ring[i]);
164			r = radeon_fence_wait(fence, false);
165			if (r)
166				return r;
167			continue;
168		}
169
170		/* we assume caller has already allocated space on waiters ring */
171		if (!radeon_semaphore_emit_wait(rdev, ring, semaphore)) {
172			/* waiting wasn't successful wait manually */
173			radeon_ring_undo(&rdev->ring[i]);
174			r = radeon_fence_wait(fence, false);
175			if (r)
176				return r;
177			continue;
178		}
179
180		radeon_ring_commit(rdev, &rdev->ring[i], false);
181		radeon_fence_note_sync(fence, ring);
182	}
183
184	return 0;
185}
186
187/**
188 * radeon_sync_free - free the sync object
189 *
190 * @rdev: radeon_device pointer
191 * @sync: sync object to use
192 * @fence: fence to use for the free
193 *
194 * Free the sync object by freeing all semaphores in it.
195 */
196void radeon_sync_free(struct radeon_device *rdev,
197		      struct radeon_sync *sync,
198		      struct radeon_fence *fence)
199{
200	unsigned i;
201
202	for (i = 0; i < RADEON_NUM_SYNCS; ++i)
203		radeon_semaphore_free(rdev, &sync->semaphores[i], fence);
204}