com32/samples/vesainfo.c

   1 /*
   2  * vesainfo.c
   3  *
   4  * Dump information about what VESA graphics modes are supported.
   5  */
   6
   7 #include <string.h>
   8 #include <stdio.h>
   9 #include <console.h>
  10 #include <com32.h>
  11 #include <inttypes.h>
  12 #include "../lib/sys/vesa/vesa.h"
  13
  14 /* Wait for a keypress */
  15 static void wait_key(void)
  16 {
  17   char ch;
  18   while (fread(&ch, 1, 1, stdin) == 0)
  19     ;
  20 }
  21
  22 static void print_modes(void)
  23 {
  24   static com32sys_t rm;
  25   struct vesa_general_info *gi;
  26   struct vesa_mode_info *mi;
  27   uint16_t mode, *mode_ptr;
  28   int lines;
  29
  30   /* Allocate space in the bounce buffer for these structures */
  31   gi = &((struct vesa_info *)__com32.cs_bounce)->gi;
  32   mi = &((struct vesa_info *)__com32.cs_bounce)->mi;
  33
  34   gi->signature = VBE2_MAGIC;   /* Get VBE2 extended data */
  35   rm.eax.w[0] = 0x4F00;         /* Get SVGA general information */
  36   rm.edi.w[0] = OFFS(gi);
  37   rm.es      = SEG(gi);
  38   __intcall(0x10, &rm, &rm);
  39
  40   if ( rm.eax.w[0] != 0x004F ) {
  41     printf("No VESA BIOS detected\n");
  42     return;
  43   } else if ( gi->signature != VESA_MAGIC ) {
  44     printf("VESA information structure has bad magic, trying anyway...\n");
  45   }
  46
  47   printf("VBE version %d.%d\n"
  48          "Mode   attrib h_res v_res bpp layout rpos gpos bpos\n",
  49          (gi->version >> 8) & 0xff, gi->version & 0xff);
  50
  51   lines = 1;
  52
  53   mode_ptr = GET_PTR(gi->video_mode_ptr);
  54
  55   while ((mode = *mode_ptr++) != 0xFFFF) {
  56     if (++lines >= 23) {
  57       wait_key();
  58       lines = 0;
  59     }
  60
  61     rm.eax.w[0] = 0x4F01;       /* Get SVGA mode information */
  62     rm.ecx.w[0] = mode;
  63     rm.edi.w[0] = OFFS(mi);
  64     rm.es  = SEG(mi);
  65     __intcall(0x10, &rm, &rm);
  66
  67     /* Must be a supported mode */
  68     if ( rm.eax.w[0] != 0x004f )
  69       continue;
  70
  71     printf("0x%04x 0x%04x %5u %5u %3u %6u %4u %4u %4u\n",
  72            mode, mi->mode_attr, mi->h_res, mi->v_res, mi->bpp,
  73            mi->memory_layout, mi->rpos, mi->gpos, mi->bpos);
  74   }
  75 }
  76
  77 int main(void)
  78 {
  79   openconsole(&dev_rawcon_r, &dev_stdcon_w);
  80
  81   print_modes();
  82   return 0;
  83 }