arch/common/boot/grub2/commands/i386/pc/vbeinfo.c

   1 /* vbeinfo.c - command to list compatible VBE video modes.  */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2005,2007  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/normal.h>
  21 #include <grub/dl.h>
  22 #include <grub/arg.h>
  23 #include <grub/env.h>
  24 #include <grub/misc.h>
  25 #include <grub/machine/init.h>
  26 #include <grub/machine/vbe.h>
  27 #include <grub/mm.h>
  28
  29 static void *
  30 real2pm (grub_vbe_farptr_t ptr)
  31 {
  32   return (void *) ((((unsigned long) ptr & 0xFFFF0000) >> 12UL)
  33                    + ((unsigned long) ptr & 0x0000FFFF));
  34 }
  35
  36 static grub_err_t
  37 grub_cmd_vbeinfo (struct grub_arg_list *state __attribute__ ((unused)),
  38                   int argc __attribute__ ((unused)),
  39                   char **args __attribute__ ((unused)))
  40 {
  41   struct grub_vbe_info_block controller_info;
  42   struct grub_vbe_mode_info_block mode_info_tmp;
  43   grub_uint32_t use_mode = GRUB_VBE_DEFAULT_VIDEO_MODE;
  44   grub_uint16_t *video_mode_list;
  45   grub_uint16_t *p;
  46   grub_uint16_t *saved_video_mode_list;
  47   grub_size_t video_mode_list_size;
  48   grub_err_t err;
  49   char *modevar;
  50
  51   err = grub_vbe_probe (&controller_info);
  52   if (err != GRUB_ERR_NONE)
  53     return err;
  54
  55   grub_printf ("VBE info:   version: %d.%d  OEM software rev: %d.%d\n",
  56                controller_info.version >> 8,
  57                controller_info.version & 0xFF,
  58                controller_info.oem_software_rev >> 8,
  59                controller_info.oem_software_rev & 0xFF);
  60
  61   /* The total_memory field is in 64 KiB units.  */
  62   grub_printf ("            total memory: %d KiB\n",
  63                (controller_info.total_memory << 16) / 1024);
  64
  65   /* Because the information on video modes is stored in a temporary place,
  66      it is better to copy it to somewhere safe.  */
  67   p = video_mode_list = real2pm (controller_info.video_mode_ptr);
  68   while (*p++ != 0xFFFF)
  69     ;
  70
  71   video_mode_list_size = (grub_addr_t) p - (grub_addr_t) video_mode_list;
  72   saved_video_mode_list = grub_malloc (video_mode_list_size);
  73   if (! saved_video_mode_list)
  74     return grub_errno;
  75
  76   grub_memcpy (saved_video_mode_list, video_mode_list, video_mode_list_size);
  77
  78   grub_printf ("List of compatible video modes:\n");
  79   grub_printf ("Legend: P=Packed pixel, D=Direct color, "
  80                "mask/pos=R/G/B/reserved\n");
  81
  82   /* Walk through all video modes listed.  */
  83   for (p = saved_video_mode_list; *p != 0xFFFF; p++)
  84     {
  85       const char *memory_model = 0;
  86       grub_uint32_t mode = (grub_uint32_t) *p;
  87
  88       err = grub_vbe_get_video_mode_info (mode, &mode_info_tmp);
  89       if (err != GRUB_ERR_NONE)
  90         {
  91           grub_errno = GRUB_ERR_NONE;
  92           continue;
  93         }
  94
  95       if ((mode_info_tmp.mode_attributes & GRUB_VBE_MODEATTR_SUPPORTED) == 0)
  96         /* If not available, skip it.  */
  97         continue;
  98
  99       if ((mode_info_tmp.mode_attributes & GRUB_VBE_MODEATTR_RESERVED_1) == 0)
 100         /* Not enough information.  */
 101         continue;
 102
 103       if ((mode_info_tmp.mode_attributes & GRUB_VBE_MODEATTR_COLOR) == 0)
 104         /* Monochrome is unusable.  */
 105         continue;
 106
 107       if ((mode_info_tmp.mode_attributes & GRUB_VBE_MODEATTR_LFB_AVAIL) == 0)
 108         /* We support only linear frame buffer modes.  */
 109         continue;
 110
 111       if ((mode_info_tmp.mode_attributes & GRUB_VBE_MODEATTR_GRAPHICS) == 0)
 112         /* We allow only graphical modes.  */
 113         continue;
 114
 115       switch (mode_info_tmp.memory_model)
 116         {
 117         case GRUB_VBE_MEMORY_MODEL_PACKED_PIXEL:
 118           memory_model = "Packed";
 119           break;
 120         case GRUB_VBE_MEMORY_MODEL_DIRECT_COLOR:
 121           memory_model = "Direct";
 122           break;
 123
 124         default:
 125           break;
 126         }
 127
 128       if (! memory_model)
 129         continue;
 130
 131       grub_printf ("0x%03x:  %4d x %4d x %2d  %s",
 132                    mode,
 133                    mode_info_tmp.x_resolution,
 134                    mode_info_tmp.y_resolution,
 135                    mode_info_tmp.bits_per_pixel,
 136                    memory_model);
 137
 138       /* Show mask and position details for direct color modes.  */
 139       if (mode_info_tmp.memory_model == GRUB_VBE_MEMORY_MODEL_DIRECT_COLOR)
 140         grub_printf (", mask: %d/%d/%d/%d  pos: %d/%d/%d/%d",
 141                      mode_info_tmp.red_mask_size,
 142                      mode_info_tmp.green_mask_size,
 143                      mode_info_tmp.blue_mask_size,
 144                      mode_info_tmp.rsvd_mask_size,
 145                      mode_info_tmp.red_field_position,
 146                      mode_info_tmp.green_field_position,
 147                      mode_info_tmp.blue_field_position,
 148                      mode_info_tmp.rsvd_field_position);
 149       grub_printf ("\n");
 150     }
 151
 152   grub_free (saved_video_mode_list);
 153
 154   /* Check existence of vbe_mode environment variable.  */
 155   modevar = grub_env_get ("vbe_mode");
 156
 157   if (modevar != 0)
 158     {
 159       unsigned long value;
 160
 161       value = grub_strtoul (modevar, 0, 0);
 162       if (grub_errno == GRUB_ERR_NONE)
 163         use_mode = value;
 164       else
 165         grub_errno = GRUB_ERR_NONE;
 166     }
 167
 168   grub_printf ("Configured VBE mode (vbe_mode) = 0x%03x\n", use_mode);
 169
 170   return 0;
 171 }
 172
 173 GRUB_MOD_INIT(vbeinfo)
 174 {
 175   (void) mod;                   /* To stop warning.  */
 176   grub_register_command ("vbeinfo",
 177                          grub_cmd_vbeinfo,
 178                          GRUB_COMMAND_FLAG_BOTH,
 179                          "vbeinfo",
 180                          "List compatible VESA BIOS extension video modes.",
 181                          0);
 182 }
 183
 184 GRUB_MOD_FINI(vbeinfo)
 185 {
 186   grub_unregister_command ("vbeinfo");
 187 }