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 #include "string.h"
  20
  21 /* VESA information */
  22 static struct vesa_general_info vginfo;
  23 static struct vesa_mode_info vminfo;
  24
  25 static __videocard video_vesa;
  26
  27 #ifndef _WAKEUP
  28 static void vesa_store_mode_params_graphics(void);
  29 #else /* _WAKEUP */
  30 static inline void vesa_store_mode_params_graphics(void) {}
  31 #endif /* _WAKEUP */
  32
  33 static int vesa_probe(void)
  34 {
  35         struct biosregs ireg, oreg;
  36         u16 mode;
  37         addr_t mode_ptr;
  38         struct mode_info *mi;
  39         int nmodes = 0;
  40
  41         video_vesa.modes = GET_HEAP(struct mode_info, 0);
  42
  43         initregs(&ireg);
  44         ireg.ax = 0x4f00;
  45         ireg.di = (size_t)&vginfo;
  46         intcall(0x10, &ireg, &oreg);
  47
  48         if (oreg.ax != 0x004f ||
  49             vginfo.signature != VESA_MAGIC ||
  50             vginfo.version < 0x0102)
  51                 return 0;       /* Not present */
  52
  53         set_fs(vginfo.video_mode_ptr.seg);
  54         mode_ptr = vginfo.video_mode_ptr.off;
  55
  56         while ((mode = rdfs16(mode_ptr)) != 0xffff) {
  57                 mode_ptr += 2;
  58
  59                 if (!heap_free(sizeof(struct mode_info)))
  60                         break;  /* Heap full, can't save mode info */
  61
  62                 if (mode & ~0x1ff)
  63                         continue;
  64
  65                 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
  66
  67                 ireg.ax = 0x4f01;
  68                 ireg.cx = mode;
  69                 ireg.di = (size_t)&vminfo;
  70                 intcall(0x10, &ireg, &oreg);
  71
  72                 if (oreg.ax != 0x004f)
  73                         continue;
  74
  75                 if ((vminfo.mode_attr & 0x15) == 0x05) {
  76                         /* Text Mode, TTY BIOS supported,
  77                            supported by hardware */
  78                         mi = GET_HEAP(struct mode_info, 1);
  79                         mi->mode  = mode + VIDEO_FIRST_VESA;
  80                         mi->depth = 0; /* text */
  81                         mi->x     = vminfo.h_res;
  82                         mi->y     = vminfo.v_res;
  83                         nmodes++;
  84                 } else if ((vminfo.mode_attr & 0x99) == 0x99 &&
  85                            (vminfo.memory_layout == 4 ||
  86                             vminfo.memory_layout == 6) &&
  87                            vminfo.memory_planes == 1) {
  88 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
  89                         /* Graphics mode, color, linear frame buffer
  90                            supported.  Only register the mode if
  91                            if framebuffer is configured, however,
  92                            otherwise the user will be left without a screen. */
  93                         mi = GET_HEAP(struct mode_info, 1);
  94                         mi->mode = mode + VIDEO_FIRST_VESA;
  95                         mi->depth = vminfo.bpp;
  96                         mi->x = vminfo.h_res;
  97                         mi->y = vminfo.v_res;
  98                         nmodes++;
  99 #endif
 100                 }
 101         }
 102
 103         return nmodes;
 104 }
 105
 106 static int vesa_set_mode(struct mode_info *mode)
 107 {
 108         struct biosregs ireg, oreg;
 109         int is_graphic;
 110         u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
 111
 112         memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
 113
 114         initregs(&ireg);
 115         ireg.ax = 0x4f01;
 116         ireg.cx = vesa_mode;
 117         ireg.di = (size_t)&vminfo;
 118         intcall(0x10, &ireg, &oreg);
 119
 120         if (oreg.ax != 0x004f)
 121                 return -1;
 122
 123         if ((vminfo.mode_attr & 0x15) == 0x05) {
 124                 /* It's a supported text mode */
 125                 is_graphic = 0;
 126 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
 127         } else if ((vminfo.mode_attr & 0x99) == 0x99) {
 128                 /* It's a graphics mode with linear frame buffer */
 129                 is_graphic = 1;
 130                 vesa_mode |= 0x4000; /* Request linear frame buffer */
 131 #endif
 132         } else {
 133                 return -1;      /* Invalid mode */
 134         }
 135
 136
 137         initregs(&ireg);
 138         ireg.ax = 0x4f02;
 139         ireg.bx = vesa_mode;
 140         intcall(0x10, &ireg, &oreg);
 141
 142         if (oreg.ax != 0x004f)
 143                 return -1;
 144
 145         graphic_mode = is_graphic;
 146         if (!is_graphic) {
 147                 /* Text mode */
 148                 force_x = mode->x;
 149                 force_y = mode->y;
 150                 do_restore = 1;
 151         } else {
 152                 /* Graphics mode */
 153                 vesa_store_mode_params_graphics();
 154         }
 155
 156         return 0;
 157 }
 158
 159
 160 #ifndef _WAKEUP
 161
 162 /* Switch DAC to 8-bit mode */
 163 static void vesa_dac_set_8bits(void)
 164 {
 165         struct biosregs ireg, oreg;
 166         u8 dac_size = 6;
 167
 168         /* If possible, switch the DAC to 8-bit mode */
 169         if (vginfo.capabilities & 1) {
 170                 initregs(&ireg);
 171                 ireg.ax = 0x4f08;
 172                 ireg.bh = 0x08;
 173                 intcall(0x10, &ireg, &oreg);
 174                 if (oreg.ax == 0x004f)
 175                         dac_size = oreg.bh;
 176         }
 177
 178         /* Set the color sizes to the DAC size, and offsets to 0 */
 179         boot_params.screen_info.red_size   = dac_size;
 180         boot_params.screen_info.green_size = dac_size;
 181         boot_params.screen_info.blue_size  = dac_size;
 182         boot_params.screen_info.rsvd_size  = dac_size;
 183
 184         boot_params.screen_info.red_pos    = 0;
 185         boot_params.screen_info.green_pos  = 0;
 186         boot_params.screen_info.blue_pos   = 0;
 187         boot_params.screen_info.rsvd_pos   = 0;
 188 }
 189
 190 /* Save the VESA protected mode info */
 191 static void vesa_store_pm_info(void)
 192 {
 193         struct biosregs ireg, oreg;
 194
 195         initregs(&ireg);
 196         ireg.ax = 0x4f0a;
 197         intcall(0x10, &ireg, &oreg);
 198
 199         if (oreg.ax != 0x004f)
 200                 return;
 201
 202         boot_params.screen_info.vesapm_seg = oreg.es;
 203         boot_params.screen_info.vesapm_off = oreg.di;
 204 }
 205
 206 /*
 207  * Save video mode parameters for graphics mode
 208  */
 209 static void vesa_store_mode_params_graphics(void)
 210 {
 211         /* Tell the kernel we're in VESA graphics mode */
 212         boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
 213
 214         /* Mode parameters */
 215         boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
 216         boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
 217         boot_params.screen_info.lfb_width = vminfo.h_res;
 218         boot_params.screen_info.lfb_height = vminfo.v_res;
 219         boot_params.screen_info.lfb_depth = vminfo.bpp;
 220         boot_params.screen_info.pages = vminfo.image_planes;
 221         boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
 222         memcpy(&boot_params.screen_info.red_size,
 223                &vminfo.rmask, 8);
 224
 225         /* General parameters */
 226         boot_params.screen_info.lfb_size = vginfo.total_memory;
 227
 228         if (vminfo.bpp <= 8)
 229                 vesa_dac_set_8bits();
 230
 231         vesa_store_pm_info();
 232 }
 233
 234 /*
 235  * Save EDID information for the kernel; this is invoked, separately,
 236  * after mode-setting.
 237  */
 238 void vesa_store_edid(void)
 239 {
 240 #ifdef CONFIG_FIRMWARE_EDID
 241         struct biosregs ireg, oreg;
 242
 243         /* Apparently used as a nonsense token... */
 244         memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
 245
 246         if (vginfo.version < 0x0200)
 247                 return;         /* EDID requires VBE 2.0+ */
 248
 249         initregs(&ireg);
 250         ireg.ax = 0x4f15;               /* VBE DDC */
 251         /* ireg.bx = 0x0000; */         /* Report DDC capabilities */
 252         /* ireg.cx = 0; */              /* Controller 0 */
 253         ireg.es = 0;                    /* ES:DI must be 0 by spec */
 254         intcall(0x10, &ireg, &oreg);
 255
 256         if (oreg.ax != 0x004f)
 257                 return;         /* No EDID */
 258
 259         /* BH = time in seconds to transfer EDD information */
 260         /* BL = DDC level supported */
 261
 262         ireg.ax = 0x4f15;               /* VBE DDC */
 263         ireg.bx = 0x0001;               /* Read EDID */
 264         /* ireg.cx = 0; */              /* Controller 0 */
 265         /* ireg.dx = 0; */              /* EDID block number */
 266         ireg.es = ds();
 267         ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
 268         intcall(0x10, &ireg, &oreg);
 269 #endif /* CONFIG_FIRMWARE_EDID */
 270 }
 271
 272 #endif /* not _WAKEUP */
 273
 274 static __videocard video_vesa =
 275 {
 276         .card_name      = "VESA",
 277         .probe          = vesa_probe,
 278         .set_mode       = vesa_set_mode,
 279         .xmode_first    = VIDEO_FIRST_VESA,
 280         .xmode_n        = 0x200,
 281 };