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