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 
33 
34 int radeon_semaphore_create(struct radeon_device *rdev,
35 			    struct radeon_semaphore **semaphore)
36 {
37 	int 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 	return 0;
54 }
55 
56 void radeon_semaphore_emit_signal(struct radeon_device *rdev, int ring,
57 			          struct radeon_semaphore *semaphore)
58 {
59 	--semaphore->waiters;
60 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, false);
61 }
62 
63 void radeon_semaphore_emit_wait(struct radeon_device *rdev, int ring,
64 			        struct radeon_semaphore *semaphore)
65 {
66 	++semaphore->waiters;
67 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, true);
68 }
69 
70 /* caller must hold ring lock */
71 int radeon_semaphore_sync_rings(struct radeon_device *rdev,
72 				struct radeon_semaphore *semaphore,
73 				int signaler, int waiter)
74 {
75 	int r;
76 
77 	/* no need to signal and wait on the same ring */
78 	if (signaler == waiter) {
79 		return 0;
80 	}
81 
82 	/* prevent GPU deadlocks */
83 	if (!rdev->ring[signaler].ready) {
84 		dev_err(rdev->dev, "Trying to sync to a disabled ring!");
85 		return -EINVAL;
86 	}
87 
88 	r = radeon_ring_alloc(rdev, &rdev->ring[signaler], 8);
89 	if (r) {
90 		return r;
91 	}
92 	radeon_semaphore_emit_signal(rdev, signaler, semaphore);
93 	radeon_ring_commit(rdev, &rdev->ring[signaler]);
94 
95 	/* we assume caller has already allocated space on waiters ring */
96 	radeon_semaphore_emit_wait(rdev, waiter, semaphore);
97 
98 	/* for debugging lockup only, used by sysfs debug files */
99 	rdev->ring[signaler].last_semaphore_signal_addr = semaphore->gpu_addr;
100 	rdev->ring[waiter].last_semaphore_wait_addr = semaphore->gpu_addr;
101 
102 	return 0;
103 }
104 
105 void radeon_semaphore_free(struct radeon_device *rdev,
106 			   struct radeon_semaphore **semaphore,
107 			   struct radeon_fence *fence)
108 {
109 	if (semaphore == NULL || *semaphore == NULL) {
110 		return;
111 	}
112 	if ((*semaphore)->waiters > 0) {
113 		dev_err(rdev->dev, "semaphore %p has more waiters than signalers,"
114 			" hardware lockup imminent!\n", *semaphore);
115 	}
116 	radeon_sa_bo_free(rdev, &(*semaphore)->sa_bo, fence);
117 	kfree(*semaphore);
118 	*semaphore = NULL;
119 }
120