xref: /openbmc/u-boot/drivers/video/videomodes.c (revision 33b1d3f4)
1 /*
2  * (C) Copyright 2004
3  * Pierre Aubert, Staubli Faverges , <p.aubert@staubli.com>
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 /************************************************************************
25   Get Parameters for the video mode:
26   The default video mode can be defined in CONFIG_SYS_DEFAULT_VIDEO_MODE.
27   If undefined, default video mode is set to 0x301
28   Parameters can be set via the variable "videomode" in the environment.
29   2 diferent ways are possible:
30   "videomode=301"   - 301 is a hexadecimal number describing the VESA
31 		      mode. Following modes are implemented:
32 
33 		      Colors	640x480 800x600 1024x768 1152x864 1280x1024
34 		     --------+---------------------------------------------
35 		      8 bits |	0x301	0x303	 0x305	  0x161	    0x307
36 		     15 bits |	0x310	0x313	 0x316	  0x162	    0x319
37 		     16 bits |	0x311	0x314	 0x317	  0x163	    0x31A
38 		     24 bits |	0x312	0x315	 0x318	    ?	    0x31B
39 		     --------+---------------------------------------------
40   "videomode=bootargs"
41 		   - the parameters are parsed from the bootargs.
42 		      The format is "NAME:VALUE,NAME:VALUE" etc.
43 		      Ex.:
44 		      "bootargs=video=ctfb:x:800,y:600,depth:16,pclk:25000"
45 		      Parameters not included in the list will be taken from
46 		      the default mode, which is one of the following:
47 		      mode:0  640x480x24
48 		      mode:1  800x600x16
49 		      mode:2  1024x768x8
50 		      mode:3  960x720x24
51 		      mode:4  1152x864x16
52 		      mode:5  1280x1024x8
53 
54 		      if "mode" is not provided within the parameter list,
55 		      mode:0 is assumed.
56 		      Following parameters are supported:
57 		      x	      xres = visible resolution horizontal
58 		      y	      yres = visible resolution vertical
59 		      pclk    pixelclocks in pico sec
60 		      le      left_marging time from sync to picture in pixelclocks
61 		      ri      right_marging time from picture to sync in pixelclocks
62 		      up      upper_margin time from sync to picture
63 		      lo      lower_margin
64 		      hs      hsync_len length of horizontal sync
65 		      vs      vsync_len length of vertical sync
66 		      sync    see FB_SYNC_*
67 		      vmode   see FB_VMODE_*
68 		      depth   Color depth in bits per pixel
69 		      All other parameters in the variable bootargs are ignored.
70 		      It is also possible to set the parameters direct in the
71 		      variable "videomode", or in another variable i.e.
72 		      "myvideo" and setting the variable "videomode=myvideo"..
73 ****************************************************************************/
74 
75 #include <common.h>
76 #include "videomodes.h"
77 
78 const struct ctfb_vesa_modes vesa_modes[VESA_MODES_COUNT] = {
79 	{0x301, RES_MODE_640x480, 8},
80 	{0x310, RES_MODE_640x480, 15},
81 	{0x311, RES_MODE_640x480, 16},
82 	{0x312, RES_MODE_640x480, 24},
83 	{0x303, RES_MODE_800x600, 8},
84 	{0x313, RES_MODE_800x600, 15},
85 	{0x314, RES_MODE_800x600, 16},
86 	{0x315, RES_MODE_800x600, 24},
87 	{0x305, RES_MODE_1024x768, 8},
88 	{0x316, RES_MODE_1024x768, 15},
89 	{0x317, RES_MODE_1024x768, 16},
90 	{0x318, RES_MODE_1024x768, 24},
91 	{0x161, RES_MODE_1152x864, 8},
92 	{0x162, RES_MODE_1152x864, 15},
93 	{0x163, RES_MODE_1152x864, 16},
94 	{0x307, RES_MODE_1280x1024, 8},
95 	{0x319, RES_MODE_1280x1024, 15},
96 	{0x31A, RES_MODE_1280x1024, 16},
97 	{0x31B, RES_MODE_1280x1024, 24},
98 };
99 const struct ctfb_res_modes res_mode_init[RES_MODES_COUNT] = {
100 	/* x	 y pixclk   le	ri  up	lo   hs vs  s  vmode */
101 	{640, 480, 39721, 40, 24, 32, 11, 96, 2, 0, FB_VMODE_NONINTERLACED},
102 	{800, 600, 27778, 64, 24, 22, 1, 72, 2, 0, FB_VMODE_NONINTERLACED},
103 	{1024, 768, 15384, 168, 8, 29, 3, 144, 4, 0, FB_VMODE_NONINTERLACED},
104 	{960, 720, 13100, 160, 40, 32, 8, 80, 4, 0, FB_VMODE_NONINTERLACED},
105 	{1152, 864, 12004, 200, 64, 32, 16, 80, 4, 0, FB_VMODE_NONINTERLACED},
106 	{1280, 1024, 9090, 200, 48, 26, 1, 184, 3, 0, FB_VMODE_NONINTERLACED},
107 };
108 
109 /************************************************************************
110  * Get Parameters for the video mode:
111  */
112 /*********************************************************************
113  * returns the length to the next seperator
114  */
115 static int
116 video_get_param_len (char *start, char sep)
117 {
118 	int i = 0;
119 	while ((*start != 0) && (*start != sep)) {
120 		start++;
121 		i++;
122 	}
123 	return i;
124 }
125 
126 static int
127 video_search_param (char *start, char *param)
128 {
129 	int len, totallen, i;
130 	char *p = start;
131 	len = strlen (param);
132 	totallen = len + strlen (start);
133 	for (i = 0; i < totallen; i++) {
134 		if (strncmp (p++, param, len) == 0)
135 			return (i);
136 	}
137 	return -1;
138 }
139 
140 /***************************************************************
141  * Get parameter via the environment as it is done for the
142  * linux kernel i.e:
143  * video=ctfb:x:800,xv:1280,y:600,yv:1024,depth:16,mode:0,pclk:25000,
144  *	 le:56,ri:48,up:26,lo:5,hs:152,vs:2,sync:0,vmode:0,accel:0
145  *
146  * penv is a pointer to the environment, containing the string, or the name of
147  * another environment variable. It could even be the term "bootargs"
148  */
149 
150 #define GET_OPTION(name,var)				\
151 	if(strncmp(p,name,strlen(name))==0) {		\
152 		val_s=p+strlen(name);			\
153 		var=simple_strtoul(val_s, NULL, 10);	\
154 	}
155 
156 int video_get_params (struct ctfb_res_modes *pPar, char *penv)
157 {
158 	char *p, *s, *val_s;
159 	int i = 0, t;
160 	int bpp;
161 	int mode;
162 	/* first search for the environment containing the real param string */
163 	s = penv;
164 	if ((p = getenv (s)) != NULL) {
165 		s = p;
166 	}
167 	/* in case of the bootargs line, we have to start
168 	 * after "video=ctfb:"
169 	 */
170 	i = video_search_param (s, "video=ctfb:");
171 	if (i >= 0) {
172 		s += i;
173 		s += strlen ("video=ctfb:");
174 	}
175 	/* search for mode as a default value */
176 	p = s;
177 	t = 0;
178 	mode = 0;		/* default */
179 	while ((i = video_get_param_len (p, ',')) != 0) {
180 		GET_OPTION ("mode:", mode)
181 			p += i;
182 		if (*p != 0)
183 			p++;	/* skip ',' */
184 	}
185 	if (mode >= RES_MODES_COUNT)
186 		mode = 0;
187 	*pPar = res_mode_init[mode];	/* copy default values */
188 	bpp = 24 - ((mode % 3) * 8);
189 	p = s;			/* restart */
190 	while ((i = video_get_param_len (p, ',')) != 0) {
191 		GET_OPTION ("x:", pPar->xres)
192 			GET_OPTION ("y:", pPar->yres)
193 			GET_OPTION ("le:", pPar->left_margin)
194 			GET_OPTION ("ri:", pPar->right_margin)
195 			GET_OPTION ("up:", pPar->upper_margin)
196 			GET_OPTION ("lo:", pPar->lower_margin)
197 			GET_OPTION ("hs:", pPar->hsync_len)
198 			GET_OPTION ("vs:", pPar->vsync_len)
199 			GET_OPTION ("sync:", pPar->sync)
200 			GET_OPTION ("vmode:", pPar->vmode)
201 			GET_OPTION ("pclk:", pPar->pixclock)
202 			GET_OPTION ("depth:", bpp)
203 			p += i;
204 		if (*p != 0)
205 			p++;	/* skip ',' */
206 	}
207 	return bpp;
208 }
209