Fixed case where the screen was cleared during a panic

[tpg/acess2.git] / Kernel / arch / x86 / kpanic.c

diff --git a/Kernel/arch/x86/kpanic.c b/Kernel/arch/x86/kpanic.c
index 505f698..1972fd3 100644 (file)
--- a/Kernel/arch/x86/kpanic.c
+++ b/Kernel/arch/x86/kpanic.c
@@ -7,21 +7,81 @@
 #include <acess.h>
 
 #define        FB      ((Uint16 *)(KERNEL_BASE|0xB8000))
+#define BGC    0x4F00  // White on Red
+//#define BGC  0xC000  // Black on Bright Red
+//#define BGC  0x1F00  // White on Blue (BSOD!)
 
  int   giKP_Pos = 0;
 
+const struct {
+       Uint16  IdxPort;
+       Uint16  DatPort;
+       Uint8   Index;
+       Uint8   Value;
+}      caRegValues[] = {
+       //{0x3C0, 0x3C0, 0x10, 0x0C},   // Mode Control (Blink Enabled)
+       {0x3C0, 0x3C0, 0x10, 0x04},     // Mode Control (Blink Disabled)
+       {0x3C0, 0x3C0, 0x11, 0x00},     // Overscan Register
+       {0x3C0, 0x3C0, 0x12, 0x0F},     // Color Plane Enable
+       {0x3C0, 0x3C0, 0x13, 0x08},     // Horizontal Panning
+       {0x3C0, 0x3C0, 0x14, 0x00},     // Color Select
+       {0    , 0x3C2, 0   , 0x67},     // Miscellaneous Output Register
+       {0x3C4, 0x3C5, 0x01, 0x00},     // Clock Mode Register
+       {0x3C4, 0x3C5, 0x03, 0x00},     // Character select
+       {0x3C4, 0x3C5, 0x04, 0x07},     // Memory Mode Register
+       {0x3CE, 0x3CF, 0x05, 0x10},     // Mode Register
+       {0x3CE, 0x3CF, 0x06, 0x0E},     // Miscellaneous Register
+       {0x3D4, 0x3D5, 0x00, 0x5F},     // Horizontal Total
+       {0x3D4, 0x3D5, 0x01, 0x4F},     // Horizontal Display Enable End
+       {0x3D4, 0x3D5, 0x02, 0x50},     // Horizontal Blank Start
+       {0x3D4, 0x3D5, 0x03, 0x82},     // Horizontal Blank End
+       {0x3D4, 0x3D5, 0x04, 0x55},     // Horizontal Retrace Start
+       {0x3D4, 0x3D5, 0x05, 0x81},     // Horizontal Retrace End
+       {0x3D4, 0x3D5, 0x06, 0xBF},     // Vertical Total
+       {0x3D4, 0x3D5, 0x07, 0x1F},     // Overflow Register
+       {0x3D4, 0x3D5, 0x08, 0x00},     // Preset row scan
+       {0x3D4, 0x3D5, 0x09, 0x4F},     // Maximum Scan Line
+       {0x3D4, 0x3D5, 0x10, 0x9C},     // Vertical Retrace Start
+       {0x3D4, 0x3D5, 0x11, 0x8E},     // Vertical Retrace End
+       {0x3D4, 0x3D5, 0x12, 0x8F},     // Vertical Display Enable End
+       {0x3D4, 0x3D5, 0x13, 0x28},     // Logical Width
+       {0x3D4, 0x3D5, 0x14, 0x1F},     // Underline Location
+       {0x3D4, 0x3D5, 0x15, 0x96},     // Vertical Blank Start
+       {0x3D4, 0x3D5, 0x16, 0xB9},     // Vertical Blank End
+       {0x3D4, 0x3D5, 0x17, 0xA3}      // CRTC Mode Control
+};
+#define        NUM_REGVALUES   (sizeof(caRegValues)/sizeof(caRegValues[0]))
+
 /**
  * \brief Sets the screen mode for a kernel panic
  */
 void KernelPanic_SetMode()
 {
         int    i;
+       
+       // Some routines call this function twice, let's avoid that, shall we?
+       if( giKP_Pos )  return ;
+       
        // Restore VGA 0xB8000 text mode
+       #if 1
+       for( i = 0; i < NUM_REGVALUES; i++ )
+       {
+               // Reset Flip-Flop
+               if( caRegValues[i].IdxPort == 0x3C0 )   inb(0x3DA);
+               
+               if( caRegValues[i].IdxPort )
+                       outb(caRegValues[i].IdxPort, caRegValues[i].Index);
+               outb(caRegValues[i].DatPort, caRegValues[i].Value);
+       }
+       
+       inb(0x3DA);
+       outb(0x3C0, 0x20);
+       #endif
        
        // Clear Screen
        for( i = 0; i < 80*25; i++ )
        {
-               FB[i] = 0x4F00;
+               FB[i] = BGC;
        }
 }