xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/virtio/virtgpu_fence.c (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1 /*	$NetBSD: virtgpu_fence.c,v 1.2 2018/08/27 04:58:37 riastradh Exp $	*/
2 
3 /*
4  * Copyright (C) 2015 Red Hat, Inc.
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining
8  * a copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sublicense, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the
16  * next paragraph) shall be included in all copies or substantial
17  * portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
22  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
23  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
24  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
25  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: virtgpu_fence.c,v 1.2 2018/08/27 04:58:37 riastradh Exp $");
30 
31 #include <drm/drmP.h>
32 #include "virtgpu_drv.h"
33 
34 static const char *virtio_get_driver_name(struct fence *f)
35 {
36 	return "virtio_gpu";
37 }
38 
39 static const char *virtio_get_timeline_name(struct fence *f)
40 {
41 	return "controlq";
42 }
43 
44 static bool virtio_enable_signaling(struct fence *f)
45 {
46 	return true;
47 }
48 
49 static bool virtio_signaled(struct fence *f)
50 {
51 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
52 
53 	if (atomic64_read(&fence->drv->last_seq) >= fence->seq)
54 		return true;
55 	return false;
56 }
57 
58 static void virtio_fence_value_str(struct fence *f, char *str, int size)
59 {
60 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
61 
62 	snprintf(str, size, "%llu", fence->seq);
63 }
64 
65 static void virtio_timeline_value_str(struct fence *f, char *str, int size)
66 {
67 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
68 
69 	snprintf(str, size, "%llu", (u64)atomic64_read(&fence->drv->last_seq));
70 }
71 
72 static const struct fence_ops virtio_fence_ops = {
73 	.get_driver_name     = virtio_get_driver_name,
74 	.get_timeline_name   = virtio_get_timeline_name,
75 	.enable_signaling    = virtio_enable_signaling,
76 	.signaled            = virtio_signaled,
77 	.wait                = fence_default_wait,
78 	.fence_value_str     = virtio_fence_value_str,
79 	.timeline_value_str  = virtio_timeline_value_str,
80 };
81 
82 int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
83 			  struct virtio_gpu_ctrl_hdr *cmd_hdr,
84 			  struct virtio_gpu_fence **fence)
85 {
86 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
87 	unsigned long irq_flags;
88 
89 	*fence = kmalloc(sizeof(struct virtio_gpu_fence), GFP_ATOMIC);
90 	if ((*fence) == NULL)
91 		return -ENOMEM;
92 
93 	spin_lock_irqsave(&drv->lock, irq_flags);
94 	(*fence)->drv = drv;
95 	(*fence)->seq = ++drv->sync_seq;
96 	fence_init(&(*fence)->f, &virtio_fence_ops, &drv->lock,
97 		   0, (*fence)->seq);
98 	fence_get(&(*fence)->f);
99 	list_add_tail(&(*fence)->node, &drv->fences);
100 	spin_unlock_irqrestore(&drv->lock, irq_flags);
101 
102 	cmd_hdr->flags |= cpu_to_le32(VIRTIO_GPU_FLAG_FENCE);
103 	cmd_hdr->fence_id = cpu_to_le64((*fence)->seq);
104 	return 0;
105 }
106 
107 void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
108 				    u64 last_seq)
109 {
110 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
111 	struct virtio_gpu_fence *fence, *tmp;
112 	unsigned long irq_flags;
113 
114 	spin_lock_irqsave(&drv->lock, irq_flags);
115 	atomic64_set(&vgdev->fence_drv.last_seq, last_seq);
116 	list_for_each_entry_safe(fence, tmp, &drv->fences, node) {
117 		if (last_seq < fence->seq)
118 			continue;
119 		fence_signal_locked(&fence->f);
120 		list_del(&fence->node);
121 		fence_put(&fence->f);
122 	}
123 	spin_unlock_irqrestore(&drv->lock, irq_flags);
124 }
125