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 #if defined(CONFIG_VIDEO_VESA) || defined(CONFIG_FIRMWARE_EDID)
  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 #endif /* CONFIG_VIDEO_VESA || CONFIG_FIRMWARE_EDID */
  53 #ifdef CONFIG_VIDEO_VESA
  54         set_fs(vginfo.video_mode_ptr.seg);
  55         mode_ptr = vginfo.video_mode_ptr.off;
  56
  57         while ((mode = rdfs16(mode_ptr)) != 0xffff) {
  58                 mode_ptr += 2;
  59
  60                 if (!heap_free(sizeof(struct mode_info)))
  61                         break;  /* Heap full, can't save mode info */
  62
  63                 if (mode & ~0x1ff)
  64                         continue;
  65
  66                 memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
  67
  68                 ireg.ax = 0x4f01;
  69                 ireg.cx = mode;
  70                 ireg.di = (size_t)&vminfo;
  71                 intcall(0x10, &ireg, &oreg);
  72
  73                 if (oreg.ax != 0x004f)
  74                         continue;
  75
  76                 if ((vminfo.mode_attr & 0x15) == 0x05) {
  77                         /* Text Mode, TTY BIOS supported,
  78                            supported by hardware */
  79                         mi = GET_HEAP(struct mode_info, 1);
  80                         mi->mode  = mode + VIDEO_FIRST_VESA;
  81                         mi->depth = 0; /* text */
  82                         mi->x     = vminfo.h_res;
  83                         mi->y     = vminfo.v_res;
  84                         nmodes++;
  85                 } else if ((vminfo.mode_attr & 0x99) == 0x99 &&
  86                            (vminfo.memory_layout == 4 ||
  87                             vminfo.memory_layout == 6) &&
  88                            vminfo.memory_planes == 1) {
  89 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
  90                         /* Graphics mode, color, linear frame buffer
  91                            supported.  Only register the mode if
  92                            if framebuffer is configured, however,
  93                            otherwise the user will be left without a screen. */
  94                         mi = GET_HEAP(struct mode_info, 1);
  95                         mi->mode = mode + VIDEO_FIRST_VESA;
  96                         mi->depth = vminfo.bpp;
  97                         mi->x = vminfo.h_res;
  98                         mi->y = vminfo.v_res;
  99                         nmodes++;
 100 #endif
 101                 }
 102         }
 103
 104         return nmodes;
 105 #else
 106         return 0;
 107 #endif /* CONFIG_VIDEO_VESA */
 108 }
 109
 110 static int vesa_set_mode(struct mode_info *mode)
 111 {
 112         struct biosregs ireg, oreg;
 113         int is_graphic;
 114         u16 vesa_mode = mode->mode - VIDEO_FIRST_VESA;
 115
 116         memset(&vminfo, 0, sizeof vminfo); /* Just in case... */
 117
 118         initregs(&ireg);
 119         ireg.ax = 0x4f01;
 120         ireg.cx = vesa_mode;
 121         ireg.di = (size_t)&vminfo;
 122         intcall(0x10, &ireg, &oreg);
 123
 124         if (oreg.ax != 0x004f)
 125                 return -1;
 126
 127         if ((vminfo.mode_attr & 0x15) == 0x05) {
 128                 /* It's a supported text mode */
 129                 is_graphic = 0;
 130 #ifdef CONFIG_FB_BOOT_VESA_SUPPORT
 131         } else if ((vminfo.mode_attr & 0x99) == 0x99) {
 132                 /* It's a graphics mode with linear frame buffer */
 133                 is_graphic = 1;
 134                 vesa_mode |= 0x4000; /* Request linear frame buffer */
 135 #endif
 136         } else {
 137                 return -1;      /* Invalid mode */
 138         }
 139
 140
 141         initregs(&ireg);
 142         ireg.ax = 0x4f02;
 143         ireg.bx = vesa_mode;
 144         intcall(0x10, &ireg, &oreg);
 145
 146         if (oreg.ax != 0x004f)
 147                 return -1;
 148
 149         graphic_mode = is_graphic;
 150         if (!is_graphic) {
 151                 /* Text mode */
 152                 force_x = mode->x;
 153                 force_y = mode->y;
 154                 do_restore = 1;
 155         } else {
 156                 /* Graphics mode */
 157                 vesa_store_mode_params_graphics();
 158         }
 159
 160         return 0;
 161 }
 162
 163
 164 #ifndef _WAKEUP
 165
 166 /* Switch DAC to 8-bit mode */
 167 static void vesa_dac_set_8bits(void)
 168 {
 169         struct biosregs ireg, oreg;
 170         u8 dac_size = 6;
 171
 172         /* If possible, switch the DAC to 8-bit mode */
 173         if (vginfo.capabilities & 1) {
 174                 initregs(&ireg);
 175                 ireg.ax = 0x4f08;
 176                 ireg.bh = 0x08;
 177                 intcall(0x10, &ireg, &oreg);
 178                 if (oreg.ax == 0x004f)
 179                         dac_size = oreg.bh;
 180         }
 181
 182         /* Set the color sizes to the DAC size, and offsets to 0 */
 183         boot_params.screen_info.red_size   = dac_size;
 184         boot_params.screen_info.green_size = dac_size;
 185         boot_params.screen_info.blue_size  = dac_size;
 186         boot_params.screen_info.rsvd_size  = dac_size;
 187
 188         boot_params.screen_info.red_pos    = 0;
 189         boot_params.screen_info.green_pos  = 0;
 190         boot_params.screen_info.blue_pos   = 0;
 191         boot_params.screen_info.rsvd_pos   = 0;
 192 }
 193
 194 /* Save the VESA protected mode info */
 195 static void vesa_store_pm_info(void)
 196 {
 197         struct biosregs ireg, oreg;
 198
 199         initregs(&ireg);
 200         ireg.ax = 0x4f0a;
 201         intcall(0x10, &ireg, &oreg);
 202
 203         if (oreg.ax != 0x004f)
 204                 return;
 205
 206         boot_params.screen_info.vesapm_seg = oreg.es;
 207         boot_params.screen_info.vesapm_off = oreg.di;
 208 }
 209
 210 /*
 211  * Save video mode parameters for graphics mode
 212  */
 213 static void vesa_store_mode_params_graphics(void)
 214 {
 215         /* Tell the kernel we're in VESA graphics mode */
 216         boot_params.screen_info.orig_video_isVGA = VIDEO_TYPE_VLFB;
 217
 218         /* Mode parameters */
 219         boot_params.screen_info.vesa_attributes = vminfo.mode_attr;
 220         boot_params.screen_info.lfb_linelength = vminfo.logical_scan;
 221         boot_params.screen_info.lfb_width = vminfo.h_res;
 222         boot_params.screen_info.lfb_height = vminfo.v_res;
 223         boot_params.screen_info.lfb_depth = vminfo.bpp;
 224         boot_params.screen_info.pages = vminfo.image_planes;
 225         boot_params.screen_info.lfb_base = vminfo.lfb_ptr;
 226         memcpy(&boot_params.screen_info.red_size,
 227                &vminfo.rmask, 8);
 228
 229         /* General parameters */
 230         boot_params.screen_info.lfb_size = vginfo.total_memory;
 231
 232         if (vminfo.bpp <= 8)
 233                 vesa_dac_set_8bits();
 234
 235         vesa_store_pm_info();
 236 }
 237
 238 /*
 239  * Save EDID information for the kernel; this is invoked, separately,
 240  * after mode-setting.
 241  */
 242 void vesa_store_edid(void)
 243 {
 244 #ifdef CONFIG_FIRMWARE_EDID
 245         struct biosregs ireg, oreg;
 246
 247         /* Apparently used as a nonsense token... */
 248         memset(&boot_params.edid_info, 0x13, sizeof boot_params.edid_info);
 249
 250         if (vginfo.version < 0x0200)
 251                 return;         /* EDID requires VBE 2.0+ */
 252
 253         initregs(&ireg);
 254         ireg.ax = 0x4f15;               /* VBE DDC */
 255         /* ireg.bx = 0x0000; */         /* Report DDC capabilities */
 256         /* ireg.cx = 0; */              /* Controller 0 */
 257         ireg.es = 0;                    /* ES:DI must be 0 by spec */
 258         intcall(0x10, &ireg, &oreg);
 259
 260         if (oreg.ax != 0x004f)
 261                 return;         /* No EDID */
 262
 263         /* BH = time in seconds to transfer EDD information */
 264         /* BL = DDC level supported */
 265
 266         ireg.ax = 0x4f15;               /* VBE DDC */
 267         ireg.bx = 0x0001;               /* Read EDID */
 268         /* ireg.cx = 0; */              /* Controller 0 */
 269         /* ireg.dx = 0; */              /* EDID block number */
 270         ireg.es = ds();
 271         ireg.di =(size_t)&boot_params.edid_info; /* (ES:)Pointer to block */
 272         intcall(0x10, &ireg, &oreg);
 273 #endif /* CONFIG_FIRMWARE_EDID */
 274 }
 275
 276 #endif /* not _WAKEUP */
 277
 278 static __videocard video_vesa =
 279 {
 280         .card_name      = "VESA",
 281         .probe          = vesa_probe,
 282         .set_mode       = vesa_set_mode,
 283         .xmode_first    = VIDEO_FIRST_VESA,
 284         .xmode_n        = 0x200,
 285 };