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 
34 int 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 
64 bool 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 
81 bool 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  */
106 void 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  */
128 int 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 
191 void 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 }
206