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  * $FreeBSD: head/sys/dev/drm2/radeon/radeon_semaphore.c 254885 2013-08-25 19:37:15Z dumbbell $
26  */
27 
28 /*
29  * Authors:
30  *    Christian König <deathsimple@vodafone.de>
31  */
32 #include <drm/drmP.h>
33 #include "radeon.h"
34 
35 
36 int radeon_semaphore_create(struct radeon_device *rdev,
37 			    struct radeon_semaphore **semaphore)
38 {
39 	int r;
40 
41 	*semaphore = kmalloc(sizeof(struct radeon_semaphore), DRM_MEM_DRIVER,
42 			     M_WAITOK);
43 	if (*semaphore == NULL) {
44 		return -ENOMEM;
45 	}
46 	r = radeon_sa_bo_new(rdev, &rdev->ring_tmp_bo,
47 			     &(*semaphore)->sa_bo, 8, 8, true);
48 	if (r) {
49 		drm_free(*semaphore, DRM_MEM_DRIVER);
50 		*semaphore = NULL;
51 		return r;
52 	}
53 	(*semaphore)->waiters = 0;
54 	(*semaphore)->gpu_addr = radeon_sa_bo_gpu_addr((*semaphore)->sa_bo);
55 	*((uint64_t*)radeon_sa_bo_cpu_addr((*semaphore)->sa_bo)) = 0;
56 	return 0;
57 }
58 
59 void radeon_semaphore_emit_signal(struct radeon_device *rdev, int ring,
60 			          struct radeon_semaphore *semaphore)
61 {
62 	--semaphore->waiters;
63 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, false);
64 }
65 
66 void radeon_semaphore_emit_wait(struct radeon_device *rdev, int ring,
67 			        struct radeon_semaphore *semaphore)
68 {
69 	++semaphore->waiters;
70 	radeon_semaphore_ring_emit(rdev, ring, &rdev->ring[ring], semaphore, true);
71 }
72 
73 /* caller must hold ring lock */
74 int radeon_semaphore_sync_rings(struct radeon_device *rdev,
75 				struct radeon_semaphore *semaphore,
76 				int signaler, int waiter)
77 {
78 	int r;
79 
80 	/* no need to signal and wait on the same ring */
81 	if (signaler == waiter) {
82 		return 0;
83 	}
84 
85 	/* prevent GPU deadlocks */
86 	if (!rdev->ring[signaler].ready) {
87 		dev_err(rdev->dev, "Trying to sync to a disabled ring!");
88 		return -EINVAL;
89 	}
90 
91 	r = radeon_ring_alloc(rdev, &rdev->ring[signaler], 8);
92 	if (r) {
93 		return r;
94 	}
95 	radeon_semaphore_emit_signal(rdev, signaler, semaphore);
96 	radeon_ring_commit(rdev, &rdev->ring[signaler]);
97 
98 	/* we assume caller has already allocated space on waiters ring */
99 	radeon_semaphore_emit_wait(rdev, waiter, semaphore);
100 
101 	/* for debugging lockup only, used by sysfs debug files */
102 	rdev->ring[signaler].last_semaphore_signal_addr = semaphore->gpu_addr;
103 	rdev->ring[waiter].last_semaphore_wait_addr = semaphore->gpu_addr;
104 
105 	return 0;
106 }
107 
108 void radeon_semaphore_free(struct radeon_device *rdev,
109 			   struct radeon_semaphore **semaphore,
110 			   struct radeon_fence *fence)
111 {
112 	if (semaphore == NULL || *semaphore == NULL) {
113 		return;
114 	}
115 	if ((*semaphore)->waiters > 0) {
116 		dev_err(rdev->dev, "semaphore %p has more waiters than signalers,"
117 			" hardware lockup imminent!\n", *semaphore);
118 	}
119 	radeon_sa_bo_free(rdev, &(*semaphore)->sa_bo, fence);
120 	drm_free(*semaphore, DRM_MEM_DRIVER);
121 	*semaphore = NULL;
122 }
123