1 /* tdfx_context.c -- IOCTLs for tdfx contexts -*- linux-c -*-
2  * Created: Thu Oct  7 10:50:22 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:
28  *    Rickard E. (Rik) Faith <faith@valinux.com>
29  *    Daryll Strauss <daryll@valinux.com>
30  *
31  */
32 
33 #define __NO_VERSION__
34 #include "drmP.h"
35 #include "tdfx_drv.h"
36 
37 extern drm_ctx_t tdfx_res_ctx;
38 
tdfx_alloc_queue(drm_device_t * dev)39 static int tdfx_alloc_queue(drm_device_t *dev)
40 {
41 	return drm_ctxbitmap_next(dev);
42 }
43 
tdfx_context_switch(drm_device_t * dev,int old,int new)44 int tdfx_context_switch(drm_device_t *dev, int old, int new)
45 {
46         char        buf[64];
47 
48         atomic_inc(&dev->total_ctx);
49 
50         if (test_and_set_bit(0, &dev->context_flag)) {
51                 DRM_ERROR("Reentering -- FIXME\n");
52                 return -EBUSY;
53         }
54 
55 #if DRM_DMA_HISTOGRAM
56         dev->ctx_start = get_cycles();
57 #endif
58 
59         DRM_DEBUG("Context switch from %d to %d\n", old, new);
60 
61         if (new == dev->last_context) {
62                 clear_bit(0, &dev->context_flag);
63                 return 0;
64         }
65 
66         if (drm_flags & DRM_FLAG_NOCTX) {
67                 tdfx_context_switch_complete(dev, new);
68         } else {
69                 sprintf(buf, "C %d %d\n", old, new);
70                 drm_write_string(dev, buf);
71         }
72 
73         return 0;
74 }
75 
tdfx_context_switch_complete(drm_device_t * dev,int new)76 int tdfx_context_switch_complete(drm_device_t *dev, int new)
77 {
78         dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */
79         dev->last_switch  = jiffies;
80 
81         if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
82                 DRM_ERROR("Lock isn't held after context switch\n");
83         }
84 
85 				/* If a context switch is ever initiated
86                                    when the kernel holds the lock, release
87                                    that lock here. */
88 #if DRM_DMA_HISTOGRAM
89         atomic_inc(&dev->histo.ctx[drm_histogram_slot(get_cycles()
90                                                       - dev->ctx_start)]);
91 
92 #endif
93         clear_bit(0, &dev->context_flag);
94         wake_up(&dev->context_wait);
95 
96         return 0;
97 }
98 
99 
tdfx_resctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)100 int tdfx_resctx(struct inode *inode, struct file *filp, unsigned int cmd,
101 	       unsigned long arg)
102 {
103 	drm_ctx_res_t	res;
104 	drm_ctx_t	ctx;
105 	int		i;
106 
107 	DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
108 	if (copy_from_user(&res, (drm_ctx_res_t *)arg, sizeof(res)))
109 		return -EFAULT;
110 	if (res.count >= DRM_RESERVED_CONTEXTS) {
111 		memset(&ctx, 0, sizeof(ctx));
112 		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
113 			ctx.handle = i;
114 			if (copy_to_user(&res.contexts[i],
115 					 &i,
116 					 sizeof(i)))
117 				return -EFAULT;
118 		}
119 	}
120 	res.count = DRM_RESERVED_CONTEXTS;
121 	if (copy_to_user((drm_ctx_res_t *)arg, &res, sizeof(res)))
122 		return -EFAULT;
123 	return 0;
124 }
125 
126 
tdfx_addctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)127 int tdfx_addctx(struct inode *inode, struct file *filp, unsigned int cmd,
128 	       unsigned long arg)
129 {
130 	drm_file_t	*priv	= filp->private_data;
131 	drm_device_t	*dev	= priv->dev;
132 	drm_ctx_t	ctx;
133 
134 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
135 		return -EFAULT;
136 	if ((ctx.handle = tdfx_alloc_queue(dev)) == DRM_KERNEL_CONTEXT) {
137 				/* Skip kernel's context and get a new one. */
138 		ctx.handle = tdfx_alloc_queue(dev);
139 	}
140 	DRM_DEBUG("%d\n", ctx.handle);
141 	if (ctx.handle == -1) {
142 		DRM_DEBUG("Not enough free contexts.\n");
143 				/* Should this return -EBUSY instead? */
144 		return -ENOMEM;
145 	}
146 
147 	if (copy_to_user((drm_ctx_t *)arg, &ctx, sizeof(ctx)))
148 		return -EFAULT;
149 	return 0;
150 }
151 
tdfx_modctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)152 int tdfx_modctx(struct inode *inode, struct file *filp, unsigned int cmd,
153 	unsigned long arg)
154 {
155 	drm_ctx_t ctx;
156 
157 	if (copy_from_user(&ctx, (drm_ctx_t*)arg, sizeof(ctx)))
158 		return -EFAULT;
159 	if (ctx.flags==_DRM_CONTEXT_PRESERVED)
160 		tdfx_res_ctx.handle=ctx.handle;
161 	return 0;
162 }
163 
tdfx_getctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)164 int tdfx_getctx(struct inode *inode, struct file *filp, unsigned int cmd,
165 	unsigned long arg)
166 {
167 	drm_ctx_t ctx;
168 
169 	if (copy_from_user(&ctx, (drm_ctx_t*)arg, sizeof(ctx)))
170 		return -EFAULT;
171 	/* This is 0, because we don't handle any context flags */
172 	ctx.flags = 0;
173 	if (copy_to_user((drm_ctx_t*)arg, &ctx, sizeof(ctx)))
174 		return -EFAULT;
175 	return 0;
176 }
177 
tdfx_switchctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)178 int tdfx_switchctx(struct inode *inode, struct file *filp, unsigned int cmd,
179 		   unsigned long arg)
180 {
181 	drm_file_t	*priv	= filp->private_data;
182 	drm_device_t	*dev	= priv->dev;
183 	drm_ctx_t	ctx;
184 
185 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
186 		return -EFAULT;
187 	DRM_DEBUG("%d\n", ctx.handle);
188 	return tdfx_context_switch(dev, dev->last_context, ctx.handle);
189 }
190 
tdfx_newctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)191 int tdfx_newctx(struct inode *inode, struct file *filp, unsigned int cmd,
192 		unsigned long arg)
193 {
194 	drm_file_t	*priv	= filp->private_data;
195 	drm_device_t	*dev	= priv->dev;
196 	drm_ctx_t	ctx;
197 
198 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
199 		return -EFAULT;
200 	DRM_DEBUG("%d\n", ctx.handle);
201 	tdfx_context_switch_complete(dev, ctx.handle);
202 
203 	return 0;
204 }
205 
tdfx_rmctx(struct inode * inode,struct file * filp,unsigned int cmd,unsigned long arg)206 int tdfx_rmctx(struct inode *inode, struct file *filp, unsigned int cmd,
207 	       unsigned long arg)
208 {
209 	drm_file_t      *priv   = filp->private_data;
210 	drm_device_t    *dev    = priv->dev;
211 	drm_ctx_t	ctx;
212 
213 	if (copy_from_user(&ctx, (drm_ctx_t *)arg, sizeof(ctx)))
214 		return -EFAULT;
215 	DRM_DEBUG("%d\n", ctx.handle);
216 	drm_ctxbitmap_free(dev, ctx.handle);
217 
218 	return 0;
219 }
220