drivers/video/videomodes.c

   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 }