1 /*
2  * Copyright (C) 2007 Ben Skeggs.
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 
27 #include "drmP.h"
28 #include "drm.h"
29 
30 #include <linux/ktime.h>
31 #include <linux/hrtimer.h>
32 
33 #include "nouveau_drv.h"
34 #include "nouveau_ramht.h"
35 #include "nouveau_fence.h"
36 #include "nouveau_software.h"
37 #include "nouveau_dma.h"
38 
39 void
40 nouveau_fence_context_del(struct nouveau_fence_chan *fctx)
41 {
42 	struct nouveau_fence *fence, *fnext;
43 	spin_lock(&fctx->lock);
44 	list_for_each_entry_safe(fence, fnext, &fctx->pending, head) {
45 		if (fence->work)
46 			fence->work(fence->priv, false);
47 		fence->channel = NULL;
48 		list_del(&fence->head);
49 		nouveau_fence_unref(&fence);
50 	}
51 	spin_unlock(&fctx->lock);
52 }
53 
54 void
55 nouveau_fence_context_new(struct nouveau_fence_chan *fctx)
56 {
57 	INIT_LIST_HEAD(&fctx->pending);
58 	spin_lock_init(&fctx->lock);
59 }
60 
61 void
62 nouveau_fence_update(struct nouveau_channel *chan)
63 {
64 	struct drm_device *dev = chan->dev;
65 	struct nouveau_fence_priv *priv = nv_engine(dev, NVOBJ_ENGINE_FENCE);
66 	struct nouveau_fence_chan *fctx = chan->engctx[NVOBJ_ENGINE_FENCE];
67 	struct nouveau_fence *fence, *fnext;
68 
69 	spin_lock(&fctx->lock);
70 	list_for_each_entry_safe(fence, fnext, &fctx->pending, head) {
71 		if (priv->read(chan) < fence->sequence)
72 			break;
73 
74 		if (fence->work)
75 			fence->work(fence->priv, true);
76 		fence->channel = NULL;
77 		list_del(&fence->head);
78 		nouveau_fence_unref(&fence);
79 	}
80 	spin_unlock(&fctx->lock);
81 }
82 
83 int
84 nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
85 {
86 	struct drm_device *dev = chan->dev;
87 	struct nouveau_fence_priv *priv = nv_engine(dev, NVOBJ_ENGINE_FENCE);
88 	struct nouveau_fence_chan *fctx = chan->engctx[NVOBJ_ENGINE_FENCE];
89 	int ret;
90 
91 	fence->channel  = chan;
92 	fence->timeout  = jiffies + (3 * DRM_HZ);
93 	fence->sequence = ++fctx->sequence;
94 
95 	ret = priv->emit(fence);
96 	if (!ret) {
97 		kref_get(&fence->kref);
98 		spin_lock(&fctx->lock);
99 		list_add_tail(&fence->head, &fctx->pending);
100 		spin_unlock(&fctx->lock);
101 	}
102 
103 	return ret;
104 }
105 
106 bool
107 nouveau_fence_done(struct nouveau_fence *fence)
108 {
109 	if (fence->channel)
110 		nouveau_fence_update(fence->channel);
111 	return !fence->channel;
112 }
113 
114 int
115 nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
116 {
117 	unsigned long sleep_time = NSEC_PER_MSEC / 1000;
118 	ktime_t t;
119 	int ret = 0;
120 
121 	while (!nouveau_fence_done(fence)) {
122 		if (fence->timeout && time_after_eq(jiffies, fence->timeout)) {
123 			ret = -EBUSY;
124 			break;
125 		}
126 
127 		__set_current_state(intr ? TASK_INTERRUPTIBLE :
128 					   TASK_UNINTERRUPTIBLE);
129 		if (lazy) {
130 			t = ktime_set(0, sleep_time);
131 			schedule_hrtimeout(&t, HRTIMER_MODE_REL);
132 			sleep_time *= 2;
133 			if (sleep_time > NSEC_PER_MSEC)
134 				sleep_time = NSEC_PER_MSEC;
135 		}
136 
137 		if (intr && signal_pending(current)) {
138 			ret = -ERESTARTSYS;
139 			break;
140 		}
141 	}
142 
143 	__set_current_state(TASK_RUNNING);
144 	return ret;
145 }
146 
147 int
148 nouveau_fence_sync(struct nouveau_fence *fence, struct nouveau_channel *chan)
149 {
150 	struct drm_device *dev = chan->dev;
151 	struct nouveau_fence_priv *priv = nv_engine(dev, NVOBJ_ENGINE_FENCE);
152 	struct nouveau_channel *prev;
153 	int ret = 0;
154 
155 	prev = fence ? nouveau_channel_get_unlocked(fence->channel) : NULL;
156 	if (prev) {
157 		if (unlikely(prev != chan && !nouveau_fence_done(fence))) {
158 			ret = priv->sync(fence, prev, chan);
159 			if (unlikely(ret))
160 				ret = nouveau_fence_wait(fence, true, false);
161 		}
162 		nouveau_channel_put_unlocked(&prev);
163 	}
164 
165 	return ret;
166 }
167 
168 static void
169 nouveau_fence_del(struct kref *kref)
170 {
171 	struct nouveau_fence *fence = container_of(kref, typeof(*fence), kref);
172 	kfree(fence);
173 }
174 
175 void
176 nouveau_fence_unref(struct nouveau_fence **pfence)
177 {
178 	if (*pfence)
179 		kref_put(&(*pfence)->kref, nouveau_fence_del);
180 	*pfence = NULL;
181 }
182 
183 struct nouveau_fence *
184 nouveau_fence_ref(struct nouveau_fence *fence)
185 {
186 	kref_get(&fence->kref);
187 	return fence;
188 }
189 
190 int
191 nouveau_fence_new(struct nouveau_channel *chan, struct nouveau_fence **pfence)
192 {
193 	struct nouveau_fence *fence;
194 	int ret = 0;
195 
196 	if (unlikely(!chan->engctx[NVOBJ_ENGINE_FENCE]))
197 		return -ENODEV;
198 
199 	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
200 	if (!fence)
201 		return -ENOMEM;
202 	kref_init(&fence->kref);
203 
204 	if (chan) {
205 		ret = nouveau_fence_emit(fence, chan);
206 		if (ret)
207 			nouveau_fence_unref(&fence);
208 	}
209 
210 	*pfence = fence;
211 	return ret;
212 }
213