arch/x86/boot/video-vesa.c

   1 /* -*- linux-c -*- ------------------------------------------------------- *
   2  *
   3  *   Copyright (C) 1991, 1992 Linus Torvalds
   4  *   Copyright 2007 rPath, Inc. - All Rights Reserved
   5  *   Copyright 2009 Intel Corporation; author H. Peter Anvin
   6  *
   7  *   This file is part of the Linux kernel, and is made available under
   8  *   the terms of the GNU General Public License version 2.
   9  *
  10  * ----------------------------------------------------------------------- */
  11
  12 /*
  13  * VESA text modes
  14  */
  15
  16 #include "boot.h"
  17 #include "video.h"
  18 #include "vesa.h"
  19
  20 /* VESA information */
  21 static struct vesa_general_info vginfo;
  22 static struct vesa_mode_info vminfo;
  23
  24 static __videocard video_vesa;
  25
  26 #ifndef _WAKEUP
  27 static void vesa_store_mode_params_graphics(void);
  28 #else /* _WAKEUP */
  29 static inline void vesa_store_mode_params_graphics(void) {}
  30 #endif /* _WAKEUP */
  31
  32 static int vesa_probe(void)
  33 {
  34         struct biosregs ireg, oreg;
  35         u16 mode;
  36         addr_t mode_ptr;
  37         struct mode_info *mi;
  38         int nmodes = 0;
  39
  40         video_vesa.modes = GET_HEAP(struct mode_info, 0);
  41
  42         initregs(&ireg);
  43         ireg.ax = 0x4f00;
  44         ireg.di = (size_t)&vginfo;
  45         intcall(0x10, &ireg, &oreg);
  46
  47         if (oreg.ax != 0x004f ||
  48             vginfo.signature != VESA_MAGIC ||
  49             vginfo.version < 0x0102)
  50                 return 0;       /* Not present */
  51
  52         set_fs(vginfo.video_mode_ptr.seg);
  53         mode_ptr = vginfo.video_mode_ptr.off;
  54
  55         while ((mode = rdfs16(mode_ptr)) != 0xffff) {
  56                 mode_ptr += 2;
  57
  58                 if (!heap_free(sizeof(struct mode_info)))
  59                         break;  /* Heap full, can't save mode info */
  60
  61                 if (mode & ~0x1ff)
  62                         continue;
  63
  64                 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
  65
  66                 ireg.ax = 0x4f01;
  67                 ireg.cx = mode;
  68                 ireg.di = (size_t)&vminfo;
  69                 intcall(0x10, &ireg, &oreg);
  70
  71                 if (oreg.ax != 0x004f)
  72                         continue;
  73
  74                 if ((vminfo.mode_attr & 0x15) == 0x05) {
  75                         /* Text Mode, TTY BIOS supported,
  76                            supported by hardware */
  77                         mi = GET_HEAP(struct mode_info, 1);
  78                         mi->mode  = mode + VIDEO_FIRST_VESA;
  79                         mi->depth = 0; /* text */
  80                         mi->x     = vminfo.h_res;
  81                         mi->y     = vminfo.v_res;
  82                         nmodes++;
  83                 } else if ((vminfo.mode_attr & 0x99) == 0x99 &&
  84                            (vminfo.memory_layout == 4 ||
  85                             vminfo.memory_layout == 6) &&
  86                            vminfo.memory_planes == 1) {
  87 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
  88                         /* Graphics mode, color, linear frame buffer
  89                            supported.  Only register the mode if
  90                            if framebuffer is configured, however,
  91                            otherwise the user will be left without a screen. */
  92                         mi = GET_HEAP(struct mode_info, 1);
  93                         mi->mode = mode + VIDEO_FIRST_VESA;
  94                         mi->depth = vminfo.bpp;
  95                         mi->x = vminfo.h_res;
  96                         mi->y = vminfo.v_res;
  97                         nmodes++;
  98 #endif
  99                 }
 100         }
 101
 102         return nmodes;
 103 }
 104
 105 static int vesa_set_mode(struct mode_info *mode)
 106 {
 107         struct biosregs ireg, oreg;
 108         int is_graphic;
 109         u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
 110
 111         memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
 112
 113         initregs(&ireg);
 114         ireg.ax = 0x4f01;
 115         ireg.cx = vesa_mode;
 116         ireg.di = (size_t)&vminfo;
 117         intcall(0x10, &ireg, &oreg);
 118
 119         if (oreg.ax != 0x004f)
 120                 return -1;
 121
 122         if ((vminfo.mode_attr & 0x15) == 0x05) {
 123                 /* It's a supported text mode */
 124                 is_graphic = 0;
 125 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
 126         } else if ((vminfo.mode_attr & 0x99) == 0x99) {
 127                 /* It's a graphics mode with linear frame buffer */
 128                 is_graphic = 1;
 129                 vesa_mode |= 0x4000; /* Request linear frame buffer */
 130 #endif
 131         } else {
 132                 return -1;      /* Invalid mode */
 133         }
 134
 135
 136         initregs(&ireg);
 137         ireg.ax = 0x4f02;
 138         ireg.bx = vesa_mode;
 139         intcall(0x10, &ireg, &oreg);
 140
 141         if (oreg.ax != 0x004f)
 142                 return -1;
 143
 144         graphic_mode = is_graphic;
 145         if (!is_graphic) {
 146                 /* Text mode */
 147                 force_x = mode->x;
 148                 force_y = mode->y;
 149                 do_restore = 1;
 150         } else {
 151                 /* Graphics mode */
 152                 vesa_store_mode_params_graphics();
 153         }
 154
 155         return 0;
 156 }
 157
 158
 159 #ifndef _WAKEUP
 160
 161 /* Switch DAC to 8-bit mode */
 162 static void vesa_dac_set_8bits(void)
 163 {
 164         struct biosregs ireg, oreg;
 165         u8 dac_size = 6;
 166
 167         /* If possible, switch the DAC to 8-bit mode */
 168         if (vginfo.capabilities & 1) {
 169                 initregs(&ireg);
 170                 ireg.ax = 0x4f08;
 171                 ireg.bh = 0x08;
 172                 intcall(0x10, &ireg, &oreg);
 173                 if (oreg.ax == 0x004f)
 174                         dac_size = oreg.bh;
 175         }
 176
 177         /* Set the color sizes to the DAC size, and offsets to 0 */
 178         boot_params.screen_info.red_size   = dac_size;
 179         boot_params.screen_info.green_size = dac_size;
 180         boot_params.screen_info.blue_size  = dac_size;
 181         boot_params.screen_info.rsvd_size  = dac_size;
 182
 183         boot_params.screen_info.red_pos    = 0;
 184         boot_params.screen_info.green_pos  = 0;
 185         boot_params.screen_info.blue_pos   = 0;
 186         boot_params.screen_info.rsvd_pos   = 0;
 187 }
 188
 189 /* Save the VESA protected mode info */
 190 static void vesa_store_pm_info(void)
 191 {
 192         struct biosregs ireg, oreg;
 193
 194         initregs(&ireg);
 195         ireg.ax = 0x4f0a;
 196         intcall(0x10, &ireg, &oreg);
 197
 198         if (oreg.ax != 0x004f)
 199                 return;
 200
 201         boot_params.screen_info.vesapm_seg = oreg.es;
 202         boot_params.screen_info.vesapm_off = oreg.di;
 203 }
 204
 205 /*
 206  * Save video mode parameters for graphics mode
 207  */
 208 static void vesa_store_mode_params_graphics(void)
 209 {
 210         /* Tell the kernel we're in VESA graphics mode */
 211         boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
 212
 213         /* Mode parameters */
 214         boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
 215         boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
 216         boot_params.screen_info.lfb_width = vminfo.h_res;
 217         boot_params.screen_info.lfb_height = vminfo.v_res;
 218         boot_params.screen_info.lfb_depth = vminfo.bpp;
 219         boot_params.screen_info.pages = vminfo.image_planes;
 220         boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
 221         memcpy(&boot_params.screen_info.red_size,
 222                &vminfo.rmask, 8);
 223
 224         /* General parameters */
 225         boot_params.screen_info.lfb_size = vginfo.total_memory;
 226
 227         if (vminfo.bpp <= 8)
 228                 vesa_dac_set_8bits();
 229
 230         vesa_store_pm_info();
 231 }
 232
 233 /*
 234  * Save EDID information for the kernel; this is invoked, separately,
 235  * after mode-setting.
 236  */
 237 void vesa_store_edid(void)
 238 {
 239 #ifdef CONFIG_FIRMWARE_EDID
 240         struct biosregs ireg, oreg;
 241
 242         /* Apparently used as a nonsense token... */
 243         memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
 244
 245         if (vginfo.version < 0x0200)
 246                 return;         /* EDID requires VBE 2.0+ */
 247
 248         initregs(&ireg);
 249         ireg.ax = 0x4f15;               /* VBE DDC */
 250         /* ireg.bx = 0x0000; */         /* Report DDC capabilities */
 251         /* ireg.cx = 0; */              /* Controller 0 */
 252         ireg.es = 0;                    /* ES:DI must be 0 by spec */
 253         intcall(0x10, &ireg, &oreg);
 254
 255         if (oreg.ax != 0x004f)
 256                 return;         /* No EDID */
 257
 258         /* BH = time in seconds to transfer EDD information */
 259         /* BL = DDC level supported */
 260
 261         ireg.ax = 0x4f15;               /* VBE DDC */
 262         ireg.bx = 0x0001;               /* Read EDID */
 263         /* ireg.cx = 0; */              /* Controller 0 */
 264         /* ireg.dx = 0; */              /* EDID block number */
 265         ireg.es = ds();
 266         ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
 267         intcall(0x10, &ireg, &oreg);
 268 #endif /* CONFIG_FIRMWARE_EDID */
 269 }
 270
 271 #endif /* not _WAKEUP */
 272
 273 static __videocard video_vesa =
 274 {
 275         .card_name      = "VESA",
 276         .probe          = vesa_probe,
 277         .set_mode       = vesa_set_mode,
 278         .xmode_first    = VIDEO_FIRST_VESA,
 279         .xmode_n        = 0x200,
 280 };