1 /**************************************************************************
2  *
3  * Copyright (C) 2010 VMware, Inc., Palo Alto, CA., USA
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 
29 #include "vmwgfx_drv.h"
30 
31 struct vmw_fence {
32 	struct list_head head;
33 	uint32_t sequence;
34 	struct timespec submitted;
35 };
36 
vmw_fence_queue_init(struct vmw_fence_queue * queue)37 void vmw_fence_queue_init(struct vmw_fence_queue *queue)
38 {
39 	INIT_LIST_HEAD(&queue->head);
40 	queue->lag = ns_to_timespec(0);
41 	getrawmonotonic(&queue->lag_time);
42 	spin_lock_init(&queue->lock);
43 }
44 
vmw_fence_queue_takedown(struct vmw_fence_queue * queue)45 void vmw_fence_queue_takedown(struct vmw_fence_queue *queue)
46 {
47 	struct vmw_fence *fence, *next;
48 
49 	spin_lock(&queue->lock);
50 	list_for_each_entry_safe(fence, next, &queue->head, head) {
51 		kfree(fence);
52 	}
53 	spin_unlock(&queue->lock);
54 }
55 
vmw_fence_push(struct vmw_fence_queue * queue,uint32_t sequence)56 int vmw_fence_push(struct vmw_fence_queue *queue,
57 		   uint32_t sequence)
58 {
59 	struct vmw_fence *fence = kmalloc(sizeof(*fence), GFP_KERNEL);
60 
61 	if (unlikely(!fence))
62 		return -ENOMEM;
63 
64 	fence->sequence = sequence;
65 	getrawmonotonic(&fence->submitted);
66 	spin_lock(&queue->lock);
67 	list_add_tail(&fence->head, &queue->head);
68 	spin_unlock(&queue->lock);
69 
70 	return 0;
71 }
72 
vmw_fence_pull(struct vmw_fence_queue * queue,uint32_t signaled_sequence)73 int vmw_fence_pull(struct vmw_fence_queue *queue,
74 		   uint32_t signaled_sequence)
75 {
76 	struct vmw_fence *fence, *next;
77 	struct timespec now;
78 	bool updated = false;
79 
80 	spin_lock(&queue->lock);
81 	getrawmonotonic(&now);
82 
83 	if (list_empty(&queue->head)) {
84 		queue->lag = ns_to_timespec(0);
85 		queue->lag_time = now;
86 		updated = true;
87 		goto out_unlock;
88 	}
89 
90 	list_for_each_entry_safe(fence, next, &queue->head, head) {
91 		if (signaled_sequence - fence->sequence > (1 << 30))
92 			continue;
93 
94 		queue->lag = timespec_sub(now, fence->submitted);
95 		queue->lag_time = now;
96 		updated = true;
97 		list_del(&fence->head);
98 		kfree(fence);
99 	}
100 
101 out_unlock:
102 	spin_unlock(&queue->lock);
103 
104 	return (updated) ? 0 : -EBUSY;
105 }
106 
vmw_timespec_add(struct timespec t1,struct timespec t2)107 static struct timespec vmw_timespec_add(struct timespec t1,
108 					struct timespec t2)
109 {
110 	t1.tv_sec += t2.tv_sec;
111 	t1.tv_nsec += t2.tv_nsec;
112 	if (t1.tv_nsec >= 1000000000L) {
113 		t1.tv_sec += 1;
114 		t1.tv_nsec -= 1000000000L;
115 	}
116 
117 	return t1;
118 }
119 
vmw_fifo_lag(struct vmw_fence_queue * queue)120 static struct timespec vmw_fifo_lag(struct vmw_fence_queue *queue)
121 {
122 	struct timespec now;
123 
124 	spin_lock(&queue->lock);
125 	getrawmonotonic(&now);
126 	queue->lag = vmw_timespec_add(queue->lag,
127 				      timespec_sub(now, queue->lag_time));
128 	queue->lag_time = now;
129 	spin_unlock(&queue->lock);
130 	return queue->lag;
131 }
132 
133 
vmw_lag_lt(struct vmw_fence_queue * queue,uint32_t us)134 static bool vmw_lag_lt(struct vmw_fence_queue *queue,
135 		       uint32_t us)
136 {
137 	struct timespec lag, cond;
138 
139 	cond = ns_to_timespec((s64) us * 1000);
140 	lag = vmw_fifo_lag(queue);
141 	return (timespec_compare(&lag, &cond) < 1);
142 }
143 
vmw_wait_lag(struct vmw_private * dev_priv,struct vmw_fence_queue * queue,uint32_t us)144 int vmw_wait_lag(struct vmw_private *dev_priv,
145 		 struct vmw_fence_queue *queue, uint32_t us)
146 {
147 	struct vmw_fence *fence;
148 	uint32_t sequence;
149 	int ret;
150 
151 	while (!vmw_lag_lt(queue, us)) {
152 		spin_lock(&queue->lock);
153 		if (list_empty(&queue->head))
154 			sequence = atomic_read(&dev_priv->fence_seq);
155 		else {
156 			fence = list_first_entry(&queue->head,
157 						 struct vmw_fence, head);
158 			sequence = fence->sequence;
159 		}
160 		spin_unlock(&queue->lock);
161 
162 		ret = vmw_wait_fence(dev_priv, false, sequence, true,
163 				     3*HZ);
164 
165 		if (unlikely(ret != 0))
166 			return ret;
167 
168 		(void) vmw_fence_pull(queue, sequence);
169 	}
170 	return 0;
171 }
172 
173 
174