File: /usr/src/linux/drivers/char/drm/drm_init.h
1 /* drm_init.h -- Setup/Cleanup for DRM -*- linux-c -*-
2 * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.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 * VA LINUX SYSTEMS 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
25 * OTHER DEALINGS IN THE SOFTWARE.
26 *
27 * Authors:
28 * Rickard E. (Rik) Faith <faith@valinux.com>
29 * Gareth Hughes <gareth@valinux.com>
30 */
31
32 #define __NO_VERSION__
33 #include "drmP.h"
34
35 #if 0
36 int DRM(flags) = DRM_FLAG_DEBUG;
37 #else
38 int DRM(flags) = 0;
39 #endif
40
41 /* drm_parse_option parses a single option. See description for
42 * drm_parse_options for details.
43 */
44 static void DRM(parse_option)(char *s)
45 {
46 char *c, *r;
47
48 DRM_DEBUG("\"%s\"\n", s);
49 if (!s || !*s) return;
50 for (c = s; *c && *c != ':'; c++); /* find : or \0 */
51 if (*c) r = c + 1; else r = NULL; /* remember remainder */
52 *c = '\0'; /* terminate */
53 if (!strcmp(s, "noctx")) {
54 DRM(flags) |= DRM_FLAG_NOCTX;
55 DRM_INFO("Server-mediated context switching OFF\n");
56 return;
57 }
58 if (!strcmp(s, "debug")) {
59 DRM(flags) |= DRM_FLAG_DEBUG;
60 DRM_INFO("Debug messages ON\n");
61 return;
62 }
63 DRM_ERROR("\"%s\" is not a valid option\n", s);
64 return;
65 }
66
67 /* drm_parse_options parse the insmod "drm_opts=" options, or the command-line
68 * options passed to the kernel via LILO. The grammar of the format is as
69 * follows:
70 *
71 * drm ::= 'drm_opts=' option_list
72 * option_list ::= option [ ';' option_list ]
73 * option ::= 'device:' major
74 * | 'debug'
75 * | 'noctx'
76 * major ::= INTEGER
77 *
78 * Note that 's' contains option_list without the 'drm_opts=' part.
79 *
80 * device=major,minor specifies the device number used for /dev/drm
81 * if major == 0 then the misc device is used
82 * if major == 0 and minor == 0 then dynamic misc allocation is used
83 * debug=on specifies that debugging messages will be printk'd
84 * debug=trace specifies that each function call will be logged via printk
85 * debug=off turns off all debugging options
86 *
87 */
88
89 void DRM(parse_options)(char *s)
90 {
91 char *h, *t, *n;
92
93 DRM_DEBUG("\"%s\"\n", s ?: "");
94 if (!s || !*s) return;
95
96 for (h = t = n = s; h && *h; h = n) {
97 for (; *t && *t != ';'; t++); /* find ; or \0 */
98 if (*t) n = t + 1; else n = NULL; /* remember next */
99 *t = '\0'; /* terminate */
100 DRM(parse_option)(h); /* parse */
101 }
102 }
103
104 /* drm_cpu_valid returns non-zero if the DRI will run on this CPU, and 0
105 * otherwise.
106 */
107 int DRM(cpu_valid)(void)
108 {
109 #if defined(__i386__)
110 if (boot_cpu_data.x86 == 3) return 0; /* No cmpxchg on a 386 */
111 #endif
112 #if defined(__sparc__) && !defined(__sparc_v9__)
113 return 0; /* No cmpxchg before v9 sparc. */
114 #endif
115 return 1;
116 }
117