1 /*
2  * Copyright (C) 2015 Red Hat, Inc.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a 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, sublicense, 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 above copyright notice and this permission notice (including the
14  * next paragraph) shall be included in all copies or substantial
15  * portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24  */
25 
26 #include <drm/drmP.h>
27 #include "virtgpu_drv.h"
28 
29 static const char *virtio_get_driver_name(struct dma_fence *f)
30 {
31 	return "virtio_gpu";
32 }
33 
34 static const char *virtio_get_timeline_name(struct dma_fence *f)
35 {
36 	return "controlq";
37 }
38 
39 static bool virtio_signaled(struct dma_fence *f)
40 {
41 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
42 
43 	if (atomic64_read(&fence->drv->last_seq) >= fence->seq)
44 		return true;
45 	return false;
46 }
47 
48 static void virtio_fence_value_str(struct dma_fence *f, char *str, int size)
49 {
50 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
51 
52 	snprintf(str, size, "%llu", fence->seq);
53 }
54 
55 static void virtio_timeline_value_str(struct dma_fence *f, char *str, int size)
56 {
57 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
58 
59 	snprintf(str, size, "%llu", (u64)atomic64_read(&fence->drv->last_seq));
60 }
61 
62 static const struct dma_fence_ops virtio_fence_ops = {
63 	.get_driver_name     = virtio_get_driver_name,
64 	.get_timeline_name   = virtio_get_timeline_name,
65 	.signaled            = virtio_signaled,
66 	.fence_value_str     = virtio_fence_value_str,
67 	.timeline_value_str  = virtio_timeline_value_str,
68 };
69 
70 struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev)
71 {
72 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
73 	struct virtio_gpu_fence *fence = kzalloc(sizeof(struct virtio_gpu_fence),
74 							GFP_ATOMIC);
75 	if (!fence)
76 		return fence;
77 
78 	fence->drv = drv;
79 	dma_fence_init(&fence->f, &virtio_fence_ops, &drv->lock, drv->context, 0);
80 
81 	return fence;
82 }
83 
84 int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
85 			  struct virtio_gpu_ctrl_hdr *cmd_hdr,
86 			  struct virtio_gpu_fence *fence)
87 {
88 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
89 	unsigned long irq_flags;
90 
91 	spin_lock_irqsave(&drv->lock, irq_flags);
92 	fence->seq = ++drv->sync_seq;
93 	dma_fence_get(&fence->f);
94 	list_add_tail(&fence->node, &drv->fences);
95 	spin_unlock_irqrestore(&drv->lock, irq_flags);
96 
97 	cmd_hdr->flags |= cpu_to_le32(VIRTIO_GPU_FLAG_FENCE);
98 	cmd_hdr->fence_id = cpu_to_le64(fence->seq);
99 	return 0;
100 }
101 
102 void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
103 				    u64 last_seq)
104 {
105 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
106 	struct virtio_gpu_fence *fence, *tmp;
107 	unsigned long irq_flags;
108 
109 	spin_lock_irqsave(&drv->lock, irq_flags);
110 	atomic64_set(&vgdev->fence_drv.last_seq, last_seq);
111 	list_for_each_entry_safe(fence, tmp, &drv->fences, node) {
112 		if (last_seq < fence->seq)
113 			continue;
114 		dma_fence_signal_locked(&fence->f);
115 		list_del(&fence->node);
116 		dma_fence_put(&fence->f);
117 	}
118 	spin_unlock_irqrestore(&drv->lock, irq_flags);
119 }
120