xref: /openbmc/u-boot/drivers/video/videomodes.c (revision 660da094)
1 /*
2  * (C) Copyright 2004
3  * Pierre Aubert, Staubli Faverges , <p.aubert@staubli.com>
4  * Copyright 2011 Freescale Semiconductor, Inc.
5  *
6  * See file CREDITS for list of people who contributed to this
7  * project.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of
12  * the License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22  * MA 02111-1307 USA
23  */
24 
25 /************************************************************************
26   Get Parameters for the video mode:
27   The default video mode can be defined in CONFIG_SYS_DEFAULT_VIDEO_MODE.
28   If undefined, default video mode is set to 0x301
29   Parameters can be set via the variable "videomode" in the environment.
30   2 diferent ways are possible:
31   "videomode=301"   - 301 is a hexadecimal number describing the VESA
32 		      mode. Following modes are implemented:
33 
34 		      Colors	640x480 800x600 1024x768 1152x864 1280x1024
35 		     --------+---------------------------------------------
36 		      8 bits |	0x301	0x303	 0x305	  0x161	    0x307
37 		     15 bits |	0x310	0x313	 0x316	  0x162	    0x319
38 		     16 bits |	0x311	0x314	 0x317	  0x163	    0x31A
39 		     24 bits |	0x312	0x315	 0x318	    ?	    0x31B
40 		     --------+---------------------------------------------
41   "videomode=bootargs"
42 		   - the parameters are parsed from the bootargs.
43 		      The format is "NAME:VALUE,NAME:VALUE" etc.
44 		      Ex.:
45 		      "bootargs=video=ctfb:x:800,y:600,depth:16,pclk:25000"
46 		      Parameters not included in the list will be taken from
47 		      the default mode, which is one of the following:
48 		      mode:0  640x480x24
49 		      mode:1  800x600x16
50 		      mode:2  1024x768x8
51 		      mode:3  960x720x24
52 		      mode:4  1152x864x16
53 		      mode:5  1280x1024x8
54 
55 		      if "mode" is not provided within the parameter list,
56 		      mode:0 is assumed.
57 		      Following parameters are supported:
58 		      x	      xres = visible resolution horizontal
59 		      y	      yres = visible resolution vertical
60 		      pclk    pixelclocks in pico sec
61 		      le      left_marging time from sync to picture in pixelclocks
62 		      ri      right_marging time from picture to sync in pixelclocks
63 		      up      upper_margin time from sync to picture
64 		      lo      lower_margin
65 		      hs      hsync_len length of horizontal sync
66 		      vs      vsync_len length of vertical sync
67 		      sync    see FB_SYNC_*
68 		      vmode   see FB_VMODE_*
69 		      depth   Color depth in bits per pixel
70 		      All other parameters in the variable bootargs are ignored.
71 		      It is also possible to set the parameters direct in the
72 		      variable "videomode", or in another variable i.e.
73 		      "myvideo" and setting the variable "videomode=myvideo"..
74 ****************************************************************************/
75 
76 #include <common.h>
77 #include <linux/ctype.h>
78 
79 #include "videomodes.h"
80 
81 const struct ctfb_vesa_modes vesa_modes[VESA_MODES_COUNT] = {
82 	{0x301, RES_MODE_640x480, 8},
83 	{0x310, RES_MODE_640x480, 15},
84 	{0x311, RES_MODE_640x480, 16},
85 	{0x312, RES_MODE_640x480, 24},
86 	{0x303, RES_MODE_800x600, 8},
87 	{0x313, RES_MODE_800x600, 15},
88 	{0x314, RES_MODE_800x600, 16},
89 	{0x315, RES_MODE_800x600, 24},
90 	{0x305, RES_MODE_1024x768, 8},
91 	{0x316, RES_MODE_1024x768, 15},
92 	{0x317, RES_MODE_1024x768, 16},
93 	{0x318, RES_MODE_1024x768, 24},
94 	{0x161, RES_MODE_1152x864, 8},
95 	{0x162, RES_MODE_1152x864, 15},
96 	{0x163, RES_MODE_1152x864, 16},
97 	{0x307, RES_MODE_1280x1024, 8},
98 	{0x319, RES_MODE_1280x1024, 15},
99 	{0x31A, RES_MODE_1280x1024, 16},
100 	{0x31B, RES_MODE_1280x1024, 24},
101 };
102 const struct ctfb_res_modes res_mode_init[RES_MODES_COUNT] = {
103 	/* x	 y pixclk   le	ri  up	lo   hs vs  s  vmode */
104 	{640, 480, 39721, 40, 24, 32, 11, 96, 2, 0, FB_VMODE_NONINTERLACED},
105 	{800, 600, 27778, 64, 24, 22, 1, 72, 2, 0, FB_VMODE_NONINTERLACED},
106 	{1024, 768, 15384, 168, 8, 29, 3, 144, 4, 0, FB_VMODE_NONINTERLACED},
107 	{960, 720, 13100, 160, 40, 32, 8, 80, 4, 0, FB_VMODE_NONINTERLACED},
108 	{1152, 864, 12004, 200, 64, 32, 16, 80, 4, 0, FB_VMODE_NONINTERLACED},
109 	{1280, 1024, 9090, 200, 48, 26, 1, 184, 3, 0, FB_VMODE_NONINTERLACED},
110 };
111 
112 /************************************************************************
113  * Get Parameters for the video mode:
114  */
115 /*********************************************************************
116  * returns the length to the next seperator
117  */
118 static int
119 video_get_param_len (char *start, char sep)
120 {
121 	int i = 0;
122 	while ((*start != 0) && (*start != sep)) {
123 		start++;
124 		i++;
125 	}
126 	return i;
127 }
128 
129 static int
130 video_search_param (char *start, char *param)
131 {
132 	int len, totallen, i;
133 	char *p = start;
134 	len = strlen (param);
135 	totallen = len + strlen (start);
136 	for (i = 0; i < totallen; i++) {
137 		if (strncmp (p++, param, len) == 0)
138 			return (i);
139 	}
140 	return -1;
141 }
142 
143 /***************************************************************
144  * Get parameter via the environment as it is done for the
145  * linux kernel i.e:
146  * video=ctfb:x:800,xv:1280,y:600,yv:1024,depth:16,mode:0,pclk:25000,
147  *	 le:56,ri:48,up:26,lo:5,hs:152,vs:2,sync:0,vmode:0,accel:0
148  *
149  * penv is a pointer to the environment, containing the string, or the name of
150  * another environment variable. It could even be the term "bootargs"
151  */
152 
153 #define GET_OPTION(name,var)				\
154 	if(strncmp(p,name,strlen(name))==0) {		\
155 		val_s=p+strlen(name);			\
156 		var=simple_strtoul(val_s, NULL, 10);	\
157 	}
158 
159 int video_get_params (struct ctfb_res_modes *pPar, char *penv)
160 {
161 	char *p, *s, *val_s;
162 	int i = 0, t;
163 	int bpp;
164 	int mode;
165 	/* first search for the environment containing the real param string */
166 	s = penv;
167 	if ((p = getenv (s)) != NULL) {
168 		s = p;
169 	}
170 	/* in case of the bootargs line, we have to start
171 	 * after "video=ctfb:"
172 	 */
173 	i = video_search_param (s, "video=ctfb:");
174 	if (i >= 0) {
175 		s += i;
176 		s += strlen ("video=ctfb:");
177 	}
178 	/* search for mode as a default value */
179 	p = s;
180 	t = 0;
181 	mode = 0;		/* default */
182 	while ((i = video_get_param_len (p, ',')) != 0) {
183 		GET_OPTION ("mode:", mode)
184 			p += i;
185 		if (*p != 0)
186 			p++;	/* skip ',' */
187 	}
188 	if (mode >= RES_MODES_COUNT)
189 		mode = 0;
190 	*pPar = res_mode_init[mode];	/* copy default values */
191 	bpp = 24 - ((mode % 3) * 8);
192 	p = s;			/* restart */
193 	while ((i = video_get_param_len (p, ',')) != 0) {
194 		GET_OPTION ("x:", pPar->xres)
195 			GET_OPTION ("y:", pPar->yres)
196 			GET_OPTION ("le:", pPar->left_margin)
197 			GET_OPTION ("ri:", pPar->right_margin)
198 			GET_OPTION ("up:", pPar->upper_margin)
199 			GET_OPTION ("lo:", pPar->lower_margin)
200 			GET_OPTION ("hs:", pPar->hsync_len)
201 			GET_OPTION ("vs:", pPar->vsync_len)
202 			GET_OPTION ("sync:", pPar->sync)
203 			GET_OPTION ("vmode:", pPar->vmode)
204 			GET_OPTION ("pclk:", pPar->pixclock)
205 			GET_OPTION ("depth:", bpp)
206 			p += i;
207 		if (*p != 0)
208 			p++;	/* skip ',' */
209 	}
210 	return bpp;
211 }
212 
213 /*
214  * Parse the 'video-mode' environment variable
215  *
216  * Example: "video-mode=fslfb:1280x1024-32@60,monitor=dvi".  See
217  * doc/README.video for more information on how to set the variable.
218  *
219  * @xres: returned value of X-resolution
220  * @yres: returned value of Y-resolution
221  * @depth: returned value of color depth
222  * @freq: returned value of monitor frequency
223  * @options: pointer to any remaining options, or NULL
224  *
225  * Returns 1 if valid values were found, 0 otherwise
226  */
227 int video_get_video_mode(unsigned int *xres, unsigned int *yres,
228 	unsigned int *depth, unsigned int *freq, const char **options)
229 {
230 	char *p = getenv("video-mode");
231 	if (!p)
232 		return 0;
233 
234 	/* Skip over the driver name, which we don't care about. */
235 	p = strchr(p, ':');
236 	if (!p)
237 		return 0;
238 
239 	/* Get the X-resolution*/
240 	while (*p && !isdigit(*p))
241 		p++;
242 	*xres = simple_strtoul(p, &p, 10);
243 	if (!*xres)
244 		return 0;
245 
246 	/* Get the Y-resolution */
247 	while (*p && !isdigit(*p))
248 		p++;
249 	*yres = simple_strtoul(p, &p, 10);
250 	if (!*yres)
251 		return 0;
252 
253 	/* Get the depth */
254 	while (*p && !isdigit(*p))
255 		p++;
256 	*depth = simple_strtoul(p, &p, 10);
257 	if (!*depth)
258 		return 0;
259 
260 	/* Get the frequency */
261 	while (*p && !isdigit(*p))
262 		p++;
263 	*freq = simple_strtoul(p, &p, 10);
264 	if (!*freq)
265 		return 0;
266 
267 	/* Find the extra options, if any */
268 	p = strchr(p, ',');
269 	*options = p ? p + 1 : NULL;
270 
271 	return 1;
272 }
273