drivers/video/miniport/vga/initvga.c

   1 #include "vgamp.h"
   2
   3 static VGA_REGISTERS Mode12Regs =
   4 {
   5    /* CRT Controller Registers */
   6    {0x5F, 0x4F, 0x50, 0x82, 0x54, 0x80, 0x0B, 0x3E, 0x00, 0x40, 0x00, 0x00,
   7     0x00, 0x00, 0x00, 0x59, 0xEA, 0x8C, 0xDF, 0x28, 0x00, 0xE7, 0x04, 0xE3},
   8    /* Attribute Controller Registers */
   9    {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B,
  10     0x0C, 0x0D, 0x0E, 0x0F, 0x81, 0x00, 0x0F, 0x00, 0x00},
  11    /* Graphics Controller Registers */
  12    {0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x05, 0x0F, 0xFF},
  13    /* Sequencer Registers */
  14    {0x03, 0x01, 0x0F, 0x00, 0x06},
  15    /* Misc Output Register */
  16    0xE3
  17 };
  18
  19 VGA_REGISTERS TextModeRegs;
  20
  21 static VOID FASTCALL
  22 vgaSaveRegisters(PVGA_REGISTERS Registers)
  23 {
  24    SIZE_T i;
  25
  26    for (i = 0; i < sizeof(Registers->CRT); i++)
  27    {
  28       VideoPortWritePortUchar(CRTC, i);
  29       Registers->CRT[i] = VideoPortReadPortUchar(CRTCDATA);
  30    }
  31
  32    for (i = 0; i < sizeof(Registers->Attribute); i++)
  33    {
  34       VideoPortReadPortUchar(STATUS);
  35       VideoPortWritePortUchar(ATTRIB, i);
  36       Registers->Attribute[i] = VideoPortReadPortUchar(ATTRIBREAD);
  37    }
  38
  39    for (i = 0; i < sizeof(Registers->Graphics); i++)
  40    {
  41       VideoPortWritePortUchar(GRAPHICS, i);
  42       Registers->Graphics[i] = VideoPortReadPortUchar(GRAPHICSDATA);
  43    }
  44
  45    for (i = 0; i < sizeof(Registers->Sequencer); i++)
  46    {
  47       VideoPortWritePortUchar(SEQ, i);
  48       Registers->Sequencer[i] = VideoPortReadPortUchar(SEQDATA);
  49    }
  50
  51    Registers->Misc = VideoPortReadPortUchar(MISC);
  52 }
  53
  54 static VOID FASTCALL
  55 vgaSetRegisters(PVGA_REGISTERS Registers)
  56 {
  57    SIZE_T i;
  58
  59    /* Update misc output register */
  60    VideoPortWritePortUchar(MISC, Registers->Misc);
  61
  62    /* Synchronous reset on */
  63    VideoPortWritePortUchar(SEQ, 0x00);
  64    VideoPortWritePortUchar(SEQDATA, 0x01);
  65
  66    /* Write sequencer registers */
  67    for (i = 1; i < sizeof(Registers->Sequencer); i++)
  68    {
  69       VideoPortWritePortUchar(SEQ, i);
  70       VideoPortWritePortUchar(SEQDATA, Registers->Sequencer[i]);
  71    }
  72
  73    /* Synchronous reset off */
  74    VideoPortWritePortUchar(SEQ, 0x00);
  75    VideoPortWritePortUchar(SEQDATA, 0x03);
  76
  77    /* Deprotect CRT registers 0-7 */
  78    VideoPortWritePortUchar(CRTC, 0x11);
  79    VideoPortWritePortUchar(CRTCDATA, Registers->CRT[0x11] & 0x7f);
  80
  81    /* Write CRT registers */
  82    for (i = 0; i < sizeof(Registers->CRT); i++)
  83    {
  84       VideoPortWritePortUchar(CRTC, i);
  85       VideoPortWritePortUchar(CRTCDATA, Registers->CRT[i]);
  86    }
  87
  88    /* Write graphics controller registers */
  89    for (i = 0; i < sizeof(Registers->Graphics); i++)
  90    {
  91       VideoPortWritePortUchar(GRAPHICS, i);
  92       VideoPortWritePortUchar(GRAPHICSDATA, Registers->Graphics[i]);
  93    }
  94
  95    /* Write attribute controller registers */
  96    for (i = 0; i < sizeof(Registers->Attribute); i++)
  97    {
  98       VideoPortReadPortUchar(STATUS);
  99       VideoPortWritePortUchar(ATTRIB, i);
 100       VideoPortWritePortUchar(ATTRIB, Registers->Attribute[i]);
 101    }
 102
 103    /* Renable screen. */
 104    VideoPortWritePortUchar(ATTRIB, 0x20);
 105 }
 106
 107 VOID
 108 InitVGAMode()
 109 {
 110    vgaSaveRegisters(&TextModeRegs);
 111    vgaSetRegisters(&Mode12Regs);
 112 }
 113
 114 VOID
 115 VGAResetDevice(OUT PSTATUS_BLOCK StatusBlock)
 116 {
 117    vgaSetRegisters(&TextModeRegs);
 118 }