1/*
  2 * Copyright 2011 Christian König.
  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 <deathsimple@vodafone.de>
 29 */
 30#include <drm/drmP.h>
 31#include "radeon.h"
 32#include "radeon_trace.h"
 33
 34int radeon_semaphore_create(struct radeon_device *rdev,
 35			    struct radeon_semaphore **semaphore)
 36{
 37	uint32_t *cpu_addr;
 38	int i, r;
 39
 40	*semaphore = kmalloc(sizeof(struct radeon_semaphore), GFP_KERNEL);
 41	if (*semaphore == NULL) {
 42		return -ENOMEM;
 43	}
 44	r = radeon_sa_bo_new(rdev, &rdev->ring_tmp_bo, &(*semaphore)->sa_bo,
 45			     8 * RADEON_NUM_SYNCS, 8);
 46	if (r) {
 47		kfree(*semaphore);
 48		*semaphore = NULL;
 49		return r;
 50	}
 51	(*semaphore)->waiters = 0;
 52	(*semaphore)->gpu_addr = radeon_sa_bo_gpu_addr((*semaphore)->sa_bo);
 53
 54	cpu_addr = radeon_sa_bo_cpu_addr((*semaphore)->sa_bo);
 55	for (i = 0; i < RADEON_NUM_SYNCS; ++i)
 56		cpu_addr[i] = 0;
 57
 58	for (i = 0; i < RADEON_NUM_RINGS; ++i)
 59		(*semaphore)->sync_to[i] = NULL;
 60
 61	return 0;
 62}
 63
 64bool radeon_semaphore_emit_signal(struct radeon_device *rdev, int ridx,
 65			          struct radeon_semaphore *semaphore)
 66{
 67	struct radeon_ring *ring = &rdev->ring[ridx];
 68
 69	trace_radeon_semaphore_signale(ridx, semaphore);
 70
 71	if (radeon_semaphore_ring_emit(rdev, ridx, ring, semaphore, false)) {
 72		--semaphore->waiters;
 73
 74		/* for debugging lockup only, used by sysfs debug files */
 75		ring->last_semaphore_signal_addr = semaphore->gpu_addr;
 76		return true;
 77	}
 78	return false;
 79}
 80
 81bool radeon_semaphore_emit_wait(struct radeon_device *rdev, int ridx,
 82			        struct radeon_semaphore *semaphore)
 83{
 84	struct radeon_ring *ring = &rdev->ring[ridx];
 85
 86	trace_radeon_semaphore_wait(ridx, semaphore);
 87
 88	if (radeon_semaphore_ring_emit(rdev, ridx, ring, semaphore, true)) {
 89		++semaphore->waiters;
 90
 91		/* for debugging lockup only, used by sysfs debug files */
 92		ring->last_semaphore_wait_addr = semaphore->gpu_addr;
 93		return true;
 94	}
 95	return false;
 96}
 97
 98/**
 99 * radeon_semaphore_sync_to - use the semaphore to sync to a fence
100 *
101 * @semaphore: semaphore object to add fence to
102 * @fence: fence to sync to
103 *
104 * Sync to the fence using this semaphore object
105 */
106void radeon_semaphore_sync_to(struct radeon_semaphore *semaphore,
107			      struct radeon_fence *fence)
108{
109        struct radeon_fence *other;
110
111        if (!fence)
112                return;
113
114        other = semaphore->sync_to[fence->ring];
115        semaphore->sync_to[fence->ring] = radeon_fence_later(fence, other);
116}
117
118/**
119 * radeon_semaphore_sync_rings - sync ring to all registered fences
120 *
121 * @rdev: radeon_device pointer
122 * @semaphore: semaphore object to use for sync
123 * @ring: ring that needs sync
124 *
125 * Ensure that all registered fences are signaled before letting
126 * the ring continue. The caller must hold the ring lock.
127 */
128int radeon_semaphore_sync_rings(struct radeon_device *rdev,
129				struct radeon_semaphore *semaphore,
130				int ring)
131{
132	unsigned count = 0;
133	int i, r;
134
135        for (i = 0; i < RADEON_NUM_RINGS; ++i) {
136		struct radeon_fence *fence = semaphore->sync_to[i];
137
138		/* check if we really need to sync */
139                if (!radeon_fence_need_sync(fence, ring))
140			continue;
141
142		/* prevent GPU deadlocks */
143		if (!rdev->ring[i].ready) {
144			dev_err(rdev->dev, "Syncing to a disabled ring!");
145			return -EINVAL;
146		}
147
148		if (++count > RADEON_NUM_SYNCS) {
149			/* not enough room, wait manually */
150			r = radeon_fence_wait(fence, false);
151			if (r)
152				return r;
153			continue;
154		}
155
156		/* allocate enough space for sync command */
157		r = radeon_ring_alloc(rdev, &rdev->ring[i], 16);
158		if (r) {
159			return r;
160		}
161
162		/* emit the signal semaphore */
163		if (!radeon_semaphore_emit_signal(rdev, i, semaphore)) {
164			/* signaling wasn't successful wait manually */
165			radeon_ring_undo(&rdev->ring[i]);
166			r = radeon_fence_wait(fence, false);
167			if (r)
168				return r;
169			continue;
170		}
171
172		/* we assume caller has already allocated space on waiters ring */
173		if (!radeon_semaphore_emit_wait(rdev, ring, semaphore)) {
174			/* waiting wasn't successful wait manually */
175			radeon_ring_undo(&rdev->ring[i]);
176			r = radeon_fence_wait(fence, false);
177			if (r)
178				return r;
179			continue;
180		}
181
182		radeon_ring_commit(rdev, &rdev->ring[i]);
183		radeon_fence_note_sync(fence, ring);
184
185		semaphore->gpu_addr += 8;
186	}
187
188	return 0;
189}
190
191void radeon_semaphore_free(struct radeon_device *rdev,
192			   struct radeon_semaphore **semaphore,
193			   struct radeon_fence *fence)
194{
195	if (semaphore == NULL || *semaphore == NULL) {
196		return;
197	}
198	if ((*semaphore)->waiters > 0) {
199		dev_err(rdev->dev, "semaphore %p has more waiters than signalers,"
200			" hardware lockup imminent!\n", *semaphore);
201	}
202	radeon_sa_bo_free(rdev, &(*semaphore)->sa_bo, fence);
203	kfree(*semaphore);
204	*semaphore = NULL;
205}