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/*++
Copyright (c) 1994 Microsoft Corporation
Module Name:
x86bios.c
Abstract:
This module implements the platform specific interface between a device
driver and the execution of x86 ROM bios code for the device.
--*/
#include "halp.h"
//
// Define global data.
// per default, we enable int10's but we do nort use them on our well known
// SNI graphic cards
// if we have an unknown card, we try to initialize it via the emulator and the card
// bios. if this fails, we disable int10 calls
//
ULONG HalpX86BiosInitialized = FALSE;
ULONG HalpEnableInt10Calls = TRUE;
BOOLEAN
HalCallBios (
IN ULONG BiosCommand,
IN OUT PULONG Eax,
IN OUT PULONG Ebx,
IN OUT PULONG Ecx,
IN OUT PULONG Edx,
IN OUT PULONG Esi,
IN OUT PULONG Edi,
IN OUT PULONG Ebp
)
/*++
Routine Description:
This function provides the platform specific interface between a device
driver and the execution of the x86 ROM bios code for the specified ROM
bios command.
Arguments:
BiosCommand - Supplies the ROM bios command to be emulated.
Eax to Ebp - Supplies the x86 emulation context.
Return Value:
A value of TRUE is returned if the specified function is executed.
Otherwise, a value of FALSE is returned.
--*/
{
XM86_CONTEXT Context;
//
// If the X86 BIOS Emulator has not been initialized, then return FALSE.
//
if (HalpX86BiosInitialized == FALSE) {
return FALSE;
}
//
// If the Video Adapter initialization failed and an Int10 command is
// specified, then return FALSE.
//
if (BiosCommand == 0x10){
if(HalpEnableInt10Calls == FALSE) {
return FALSE;
}
//
// if Int10 commands are still enabled, Initialize the Card
// if it fails, disable Int10's
// this should make sense ...
//
if (x86BiosInitializeAdapter(0xc0000, NULL, NULL, NULL) != XM_SUCCESS) {
HalpEnableInt10Calls = FALSE;
return FALSE;
}
}
//
// Copy the x86 bios context and emulate the specified command.
//
Context.Eax = *Eax;
Context.Ebx = *Ebx;
Context.Ecx = *Ecx;
Context.Edx = *Edx;
Context.Esi = *Esi;
Context.Edi = *Edi;
Context.Ebp = *Ebp;
if (x86BiosExecuteInterrupt((UCHAR)BiosCommand, &Context, NULL, NULL) != XM_SUCCESS) {
return FALSE;
}
//
// Copy the x86 bios context and return TRUE.
//
*Eax = Context.Eax;
*Ebx = Context.Ebx;
*Ecx = Context.Ecx;
*Edx = Context.Edx;
*Esi = Context.Esi;
*Edi = Context.Edi;
*Ebp = Context.Ebp;
return TRUE;
}
VOID
HalpResetX86DisplayAdapter(
VOID
)
/*++
Routine Description:
This function resets a display adapter using the x86 bios emulator.
Arguments:
None.
Return Value:
None.
--*/
{
XM86_CONTEXT Context;
//
// Initialize the x86 bios context and make the INT 10 call to initialize
// the display adapter to 80x50 16 color text mode.
// this is done by two int10 calls like on an standard PC
// hopefully this works ...
// the sample code sets only 80x25 mode, but we want more !!!
//
Context.Eax = 0x0003; // Function 0, Mode 3
Context.Ebx = 0;
Context.Ecx = 0;
Context.Edx = 0;
Context.Esi = 0;
Context.Edi = 0;
Context.Ebp = 0;
HalCallBios(0x10,
&Context.Eax,
&Context.Ebx,
&Context.Ecx,
&Context.Edx,
&Context.Esi,
&Context.Edi,
&Context.Ebp);
//
// Now change it to 80x50 8x8Font Mode
//
Context.Eax = 0x1112; // use 8x8 font (causes 50 line mode)
Context.Ebx = 0;
HalCallBios(0x10,
&Context.Eax,
&Context.Ebx,
&Context.Ecx,
&Context.Edx,
&Context.Esi,
&Context.Edi,
&Context.Ebp);
}