git.mutantstargoat.com Git - eightysix/blob - kern/src/disp.c

   1 #include "disp.h"
   2
   3 static void detect_video(void);
   4
   5 struct console con_disp = { clear_disp, disp_putc, 0 };
   6
   7 static uint16_t __far *vmem;
   8 static uint16_t cur_attr;
   9 static int cur_x, cur_y;
  10 static int cur_scroll;
  11 static int mono;
  12
  13 void init_disp(void)
  14 {
  15         detect_video();
  16 }
  17
  18 static void detect_video(void)
  19 {
  20         mono = 0;
  21         disp_type = DISP_UNK;
  22
  23         if(detect_vgainfo() == 0) {
  24                 goto done;
  25         }
  26         if(detect_egainfo() == 0) {
  27                 goto done;
  28         }
  29         if(detect_eqlist() == 0) {
  30                 goto done;
  31         }
  32
  33 done:
  34         vmem = mono ? MK_FP(0xb000, 0) : MK_FP(0xb800, 0);
  35 }
  36
  37 static int detect_vgainfo(void)
  38 {
  39         union regs regs;
  40
  41         regs.w.ax = 0x1a00;
  42         int86(0x10, &regs, &regs);
  43         if(regs.h.al != 0x1a) {
  44                 return -1;
  45         }
  46
  47         switch(regs.h.bl) {
  48         case 1:
  49                 disp_type = DISP_MDA;
  50                 mono = 1;
  51                 break;
  52         case 2:
  53                 disp_type = DISP_CGA;
  54                 break;
  55         case 4:
  56                 disp_type = DISP_EGA;
  57                 break;
  58         case 5:
  59                 disp_type = DISP_EGA;
  60                 mono = 1;
  61                 break;
  62         case 6:
  63                 disp_type = DISP_PGA;
  64                 break;
  65         case 7:
  66                 disp_type = DISP_VGA;
  67                 mono = 1;
  68                 break;
  69         case 8:
  70                 disp_type = DISP_VGA;
  71                 break;
  72         case 0xa:
  73         case 0xc:
  74                 disp_type = DISP_MCGA;
  75                 break;
  76         case 0xb:
  77                 disp_type = DISP_MCGA;
  78                 mono = 1;
  79                 break;
  80         default:
  81                 return -1;
  82         }
  83         return 0;
  84 }
  85
  86 static int detect_egainfo(void)
  87 {
  88         union regs regs;
  89
  90         regs.w.ax = 0x1200;
  91         regs.w.bx = 0xff10;
  92         int86(0x10, &regs, &regs);
  93         if(regs.h.bh == 0xff) {
  94                 return -1;
  95         }
  96
  97         disp_type = DISP_EGA;
  98         mono = regs.h.bh;
  99         return 0;
 100 }
 101
 102 static int detect_eqlist(void)
 103 {
 104 }