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 #ifdef TRACE_TODO
33 #include "radeon_trace.h"
34 #endif
35 
36 int radeon_semaphore_create(struct radeon_device *rdev,
37 			    struct radeon_semaphore **semaphore)
38 {
39 	uint64_t *cpu_addr;
40 	int i, r;
41 
42 	*semaphore = kmalloc(sizeof(struct radeon_semaphore), M_DRM,
43 			     M_WAITOK);
44 	if (*semaphore == NULL) {
45 		return -ENOMEM;
46 	}
47 	r = radeon_sa_bo_new(rdev, &rdev->ring_tmp_bo, &(*semaphore)->sa_bo,
48 			     8 * RADEON_NUM_SYNCS, 8);
49 	if (r) {
50 		kfree(*semaphore);
51 		*semaphore = NULL;
52 		return r;
53 	}
54 	(*semaphore)->waiters = 0;
55 	(*semaphore)->gpu_addr = radeon_sa_bo_gpu_addr((*semaphore)->sa_bo);
56 
57 	cpu_addr = radeon_sa_bo_cpu_addr((*semaphore)->sa_bo);
58 	for (i = 0; i < RADEON_NUM_SYNCS; ++i)
59 		cpu_addr[i] = 0;
60 
61 	for (i = 0; i < RADEON_NUM_RINGS; ++i)
62 		(*semaphore)->sync_to[i] = NULL;
63 
64 	return 0;
65 }
66 
67 bool radeon_semaphore_emit_signal(struct radeon_device *rdev, int ridx,
68 			          struct radeon_semaphore *semaphore)
69 {
70 	struct radeon_ring *ring = &rdev->ring[ridx];
71 
72 #ifdef TRACE_TODO
73 	trace_radeon_semaphore_signale(ridx, semaphore);
74 #endif
75 
76 	if (radeon_semaphore_ring_emit(rdev, ridx, ring, semaphore, false)) {
77 		--semaphore->waiters;
78 
79 		/* for debugging lockup only, used by sysfs debug files */
80 		ring->last_semaphore_signal_addr = semaphore->gpu_addr;
81 		return true;
82 	}
83 	return false;
84 }
85 
86 bool radeon_semaphore_emit_wait(struct radeon_device *rdev, int ridx,
87 			        struct radeon_semaphore *semaphore)
88 {
89 	struct radeon_ring *ring = &rdev->ring[ridx];
90 
91 #ifdef TRACE_TODO
92 	trace_radeon_semaphore_wait(ridx, semaphore);
93 #endif
94 
95 	if (radeon_semaphore_ring_emit(rdev, ridx, ring, semaphore, true)) {
96 		++semaphore->waiters;
97 
98 		/* for debugging lockup only, used by sysfs debug files */
99 		ring->last_semaphore_wait_addr = semaphore->gpu_addr;
100 		return true;
101 	}
102 	return false;
103 }
104 
105 /**
106  * radeon_semaphore_sync_to - use the semaphore to sync to a fence
107  *
108  * @semaphore: semaphore object to add fence to
109  * @fence: fence to sync to
110  *
111  * Sync to the fence using this semaphore object
112  */
113 void radeon_semaphore_sync_to(struct radeon_semaphore *semaphore,
114 			      struct radeon_fence *fence)
115 {
116         struct radeon_fence *other;
117 
118         if (!fence)
119                 return;
120 
121         other = semaphore->sync_to[fence->ring];
122         semaphore->sync_to[fence->ring] = radeon_fence_later(fence, other);
123 }
124 
125 /**
126  * radeon_semaphore_sync_rings - sync ring to all registered fences
127  *
128  * @rdev: radeon_device pointer
129  * @semaphore: semaphore object to use for sync
130  * @ring: ring that needs sync
131  *
132  * Ensure that all registered fences are signaled before letting
133  * the ring continue. The caller must hold the ring lock.
134  */
135 int radeon_semaphore_sync_rings(struct radeon_device *rdev,
136 				struct radeon_semaphore *semaphore,
137 				int ring)
138 {
139 	unsigned count = 0;
140 	int i, r;
141 
142         for (i = 0; i < RADEON_NUM_RINGS; ++i) {
143 		struct radeon_fence *fence = semaphore->sync_to[i];
144 
145 		/* check if we really need to sync */
146                 if (!radeon_fence_need_sync(fence, ring))
147 			continue;
148 
149 		/* prevent GPU deadlocks */
150 		if (!rdev->ring[i].ready) {
151 			dev_err(rdev->dev, "Syncing to a disabled ring!");
152 			return -EINVAL;
153 		}
154 
155 		if (++count > RADEON_NUM_SYNCS) {
156 			/* not enough room, wait manually */
157 			r = radeon_fence_wait(fence, false);
158 			if (r)
159 				return r;
160 			continue;
161 		}
162 
163 		/* allocate enough space for sync command */
164 		r = radeon_ring_alloc(rdev, &rdev->ring[i], 16);
165 		if (r) {
166 			return r;
167 		}
168 
169 		/* emit the signal semaphore */
170 		if (!radeon_semaphore_emit_signal(rdev, i, semaphore)) {
171 			/* signaling wasn't successful wait manually */
172 			radeon_ring_undo(&rdev->ring[i]);
173 			r = radeon_fence_wait(fence, false);
174 			if (r)
175 				return r;
176 			continue;
177 		}
178 
179 		/* we assume caller has already allocated space on waiters ring */
180 		if (!radeon_semaphore_emit_wait(rdev, ring, semaphore)) {
181 			/* waiting wasn't successful wait manually */
182 			radeon_ring_undo(&rdev->ring[i]);
183 			r = radeon_fence_wait(fence, false);
184 			if (r)
185 				return r;
186 			continue;
187 		}
188 
189 		radeon_ring_commit(rdev, &rdev->ring[i], false);
190 		radeon_fence_note_sync(fence, ring);
191 
192 		semaphore->gpu_addr += 8;
193 	}
194 
195 	return 0;
196 }
197 
198 void radeon_semaphore_free(struct radeon_device *rdev,
199 			   struct radeon_semaphore **semaphore,
200 			   struct radeon_fence *fence)
201 {
202 	if (semaphore == NULL || *semaphore == NULL) {
203 		return;
204 	}
205 	if ((*semaphore)->waiters > 0) {
206 		dev_err(rdev->dev, "semaphore %p has more waiters than signalers,"
207 			" hardware lockup imminent!\n", *semaphore);
208 	}
209 	radeon_sa_bo_free(rdev, &(*semaphore)->sa_bo, fence);
210 	kfree(*semaphore);
211 	*semaphore = NULL;
212 }
213