1 /* i810_context.c -- IOCTLs for i810 contexts -*- linux-c -*-
2  * Created: Mon Dec 13 09:51:35 1999 by faith@precisioninsight.com
3  *
4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6  * All Rights Reserved.
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a
9  * copy of this software and associated documentation files (the "Software"),
10  * to deal in the Software without restriction, including without limitation
11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12  * and/or sell copies of the Software, and to permit persons to whom the
13  * Software is furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the next
16  * paragraph) shall be included in all copies or substantial portions of the
17  * Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25  * DEALINGS IN THE SOFTWARE.
26  *
27  * Authors: Rickard E. (Rik) Faith <faith@valinux.com>
28  *	    Jeff Hartmann <jhartmann@valinux.com>
29  *
30  */
31 
32 #define __NO_VERSION__
33 #include "drmP.h"
34 #include "i810_drv.h"
35 
i810_alloc_queue(drm_device_t * dev)36 static int i810_alloc_queue(drm_device_t *dev)
37 {
38    	int temp = drm_ctxbitmap_next(dev);
39    	DRM_DEBUG("i810_alloc_queue: %d\n", temp);
40 	return temp;
41 }
42 
i810_context_switch(drm_device_t * dev,int old,int new)43 int i810_context_switch(drm_device_t *dev, int old, int new)
44 {
45         char        buf[64];
46 
47         atomic_inc(&dev->total_ctx);
48 
49         if (test_and_set_bit(0, &dev->context_flag)) {
50                 DRM_ERROR("Reentering -- FIXME\n");
51                 return -EBUSY;
52         }
53 
54 #if DRM_DMA_HISTOGRAM
55         dev->ctx_start = get_cycles();
56 #endif
57 
58         DRM_DEBUG("Context switch from %d to %d\n", old, new);
59 
60         if (new == dev->last_context) {
61                 clear_bit(0, &dev->context_flag);
62                 return 0;
63         }
64 
65         if (drm_flags & DRM_FLAG_NOCTX) {
66                 i810_context_switch_complete(dev, new);
67         } else {
68                 sprintf(buf, "C %d %d\n", old, new);
69                 drm_write_string(dev, buf);
70         }
71 
72         return 0;
73 }
74 
i810_context_switch_complete(drm_device_t * dev,int new)75 int i810_context_switch_complete(drm_device_t *dev, int new)
76 {
77         dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */
78         dev->last_switch  = jiffies;
79 
80         if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
81                 DRM_ERROR("Lock isn't held after context switch\n");
82         }
83 
84 				/* If a context switch is ever initiated
85                                    when the kernel holds the lock, release
86                                    that lock here. */
87 #if DRM_DMA_HISTOGRAM
88         atomic_inc(&dev->histo.ctx[drm_histogram_slot(get_cycles()
89                                                       - dev->ctx_start)]);
90 
91 #endif
92         clear_bit(0, &dev->context_flag);
93         wake_up(&dev->context_wait);
94 
95         return 0;
96 }
97 
i810_resctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)98 int i810_resctx(struct inode *inode, struct file *filp, unsigned int cmd,
99 	       unsigned long arg)
100 {
101 	drm_ctx_res_t	res;
102 	drm_ctx_t	ctx;
103 	int		i;
104 
105 	DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
106 	if (copy_from_user(&res, (drm_ctx_res_t *)arg, sizeof(res)))
107 		return -EFAULT;
108 	if (res.count >= DRM_RESERVED_CONTEXTS) {
109 		memset(&ctx, 0, sizeof(ctx));
110 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
111 			ctx.handle = i;
112 			if (copy_to_user(&res.contexts[i],
113 					 &i,
114 					 sizeof(i)))
115 				return -EFAULT;
116 		}
117 	}
118 	res.count = DRM_RESERVED_CONTEXTS;
119 	if (copy_to_user((drm_ctx_res_t *)arg, &res, sizeof(res)))
120 		return -EFAULT;
121 	return 0;
122 }
123 
i810_addctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)124 int i810_addctx(struct inode *inode, struct file *filp, unsigned int cmd,
125 	       unsigned long arg)
126 {
127 	drm_file_t	*priv	= filp->private_data;
128 	drm_device_t	*dev	= priv->dev;
129 	drm_ctx_t	ctx;
130 
131 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
132 		return -EFAULT;
133 	if ((ctx.handle = i810_alloc_queue(dev)) == DRM_KERNEL_CONTEXT) {
134 				/* Skip kernel's context and get a new one. */
135 		ctx.handle = i810_alloc_queue(dev);
136 	}
137         if (ctx.handle == -1) {
138 		DRM_DEBUG("Not enough free contexts.\n");
139 				/* Should this return -EBUSY instead? */
140 		return -ENOMEM;
141 	}
142 	DRM_DEBUG("%d\n", ctx.handle);
143 	if (copy_to_user((drm_ctx_t *)arg, &ctx, sizeof(ctx)))
144 		return -EFAULT;
145 	return 0;
146 }
147 
i810_modctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)148 int i810_modctx(struct inode *inode, struct file *filp, unsigned int cmd,
149 	unsigned long arg)
150 {
151    	/* This does nothing for the i810 */
152 	return 0;
153 }
154 
i810_getctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)155 int i810_getctx(struct inode *inode, struct file *filp, unsigned int cmd,
156 	unsigned long arg)
157 {
158 	drm_ctx_t ctx;
159 
160 	if (copy_from_user(&ctx, (drm_ctx_t*)arg, sizeof(ctx)))
161 		return -EFAULT;
162 	/* This is 0, because we don't hanlde any context flags */
163 	ctx.flags = 0;
164 	if (copy_to_user((drm_ctx_t*)arg, &ctx, sizeof(ctx)))
165 		return -EFAULT;
166 	return 0;
167 }
168 
i810_switchctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)169 int i810_switchctx(struct inode *inode, struct file *filp, unsigned int cmd,
170 		   unsigned long arg)
171 {
172 	drm_file_t	*priv	= filp->private_data;
173 	drm_device_t	*dev	= priv->dev;
174 	drm_ctx_t	ctx;
175 
176 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
177 		return -EFAULT;
178 	DRM_DEBUG("%d\n", ctx.handle);
179 	return i810_context_switch(dev, dev->last_context, ctx.handle);
180 }
181 
i810_newctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)182 int i810_newctx(struct inode *inode, struct file *filp, unsigned int cmd,
183 		unsigned long arg)
184 {
185 	drm_file_t	*priv	= filp->private_data;
186 	drm_device_t	*dev	= priv->dev;
187 	drm_ctx_t	ctx;
188 
189 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
190 		return -EFAULT;
191 	DRM_DEBUG("%d\n", ctx.handle);
192 	i810_context_switch_complete(dev, ctx.handle);
193 
194 	return 0;
195 }
196 
i810_rmctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)197 int i810_rmctx(struct inode *inode, struct file *filp, unsigned int cmd,
198 	      unsigned long arg)
199 {
200 	drm_file_t	*priv	= filp->private_data;
201 	drm_device_t	*dev	= priv->dev;
202 	drm_ctx_t	ctx;
203 
204 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
205 		return -EFAULT;
206 	DRM_DEBUG("%d\n", ctx.handle);
207    	if(ctx.handle != DRM_KERNEL_CONTEXT) {
208 	   	drm_ctxbitmap_free(dev, ctx.handle);
209 	}
210 
211 	return 0;
212 }
213