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 "drmP.h"
31 #include "drm.h"
32 #include "radeon.h"
33 
34 
35 int radeon_semaphore_create(struct radeon_device *rdev,
36 			    struct radeon_semaphore **semaphore)
37 {
38 	int 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,
45 			     &(*semaphore)->sa_bo, 8, 8, true);
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 	*((uint64_t*)radeon_sa_bo_cpu_addr((*semaphore)->sa_bo)) = 0;
54 	return 0;
55 }
56 
57 void radeon_semaphore_emit_signal(struct radeon_device *rdev, int ring,
58 			          struct radeon_semaphore *semaphore)
59 {
60 	--semaphore->waiters;
61 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, false);
62 }
63 
64 void radeon_semaphore_emit_wait(struct radeon_device *rdev, int ring,
65 			        struct radeon_semaphore *semaphore)
66 {
67 	++semaphore->waiters;
68 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, true);
69 }
70 
71 /* caller must hold ring lock */
72 int radeon_semaphore_sync_rings(struct radeon_device *rdev,
73 				struct radeon_semaphore *semaphore,
74 				int signaler, int waiter)
75 {
76 	int r;
77 
78 	/* no need to signal and wait on the same ring */
79 	if (signaler == waiter) {
80 		return 0;
81 	}
82 
83 	/* prevent GPU deadlocks */
84 	if (!rdev->ring[signaler].ready) {
85 		dev_err(rdev->dev, "Trying to sync to a disabled ring!");
86 		return -EINVAL;
87 	}
88 
89 	r = radeon_ring_alloc(rdev, &rdev->ring[signaler], 8);
90 	if (r) {
91 		return r;
92 	}
93 	radeon_semaphore_emit_signal(rdev, signaler, semaphore);
94 	radeon_ring_commit(rdev, &rdev->ring[signaler]);
95 
96 	/* we assume caller has already allocated space on waiters ring */
97 	radeon_semaphore_emit_wait(rdev, waiter, semaphore);
98 
99 	return 0;
100 }
101 
102 void radeon_semaphore_free(struct radeon_device *rdev,
103 			   struct radeon_semaphore **semaphore,
104 			   struct radeon_fence *fence)
105 {
106 	if (semaphore == NULL || *semaphore == NULL) {
107 		return;
108 	}
109 	if ((*semaphore)->waiters > 0) {
110 		dev_err(rdev->dev, "semaphore %p has more waiters than signalers,"
111 			" hardware lockup imminent!\n", *semaphore);
112 	}
113 	radeon_sa_bo_free(rdev, &(*semaphore)->sa_bo, fence);
114 	kfree(*semaphore);
115 	*semaphore = NULL;
116 }
117