windows-nt-4.0/private/ntos/nthals/halr96b/mips/x86bios.c

// #pragma comment(exestr, "@(#) x86bios.c 1.1 95/09/28 18:40:12 nec")
/*++

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.

Author:

    David N. Cutler (davec) 17-Jun-1994

Environment:

    Kernel mode only.

Revision History:

    M001 kuriyama@oa2.kb.nec.co.jp Tue Jul 18 15:45:09 JST 1995
         - add check intel based bios flag

    M002 kuriyama@oa2.kb.nec.co.jp Thu Jul 20 15:16:52 JST 1995
         - add for DPI support (NO PCI DATA structure)

    S003 kuriyama@oa2.kb.nec.co.jp Tue Aug 15 14:09:30 JST 1995
	 - bug fix for canopus PowerWindows 864PCI

--*/


#define USE_BIOS_EMULATOR



#include "halp.h"
#include "pci.h"
#include "pcip.h"
#include "xm86.h"
#include "x86new.h"

VOID
HalpReadPCIConfigUlongByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PULONG Buffer,
    IN ULONG Offset
   );

VOID
HalpWritePCIConfigUlongByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PULONG Buffer,
    IN ULONG Offset
   );

VOID
HalpReadPCIConfigUshortByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PSHORT Buffer,
    IN ULONG Offset
   );

VOID
HalpWritePCIConfigUshortByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PSHORT Buffer,
    IN ULONG Offset
   );

// M001 +++
VOID
HalpReadPCIConfigUcharByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PUCHAR Buffer,
    IN ULONG Offset
   );

VOID
HalpWritePCIConfigUcharByOffset (
    IN PCI_SLOT_NUMBER Slot,
    IN PUCHAR Buffer,
    IN ULONG Offset
   );
// M001 ---

//
// Define global data.
//


ULONG HalpX86BiosInitialized = FALSE;
ULONG HalpEnableInt10Calls = FALSE;
PVOID HalpIoMemoryBase = NULL;
PVOID HalpIoControlBase=NULL;
PUCHAR HalpRomBase = NULL;

ULONG ROM_Length;
#define BUFFER_SIZE (64*1024)
UCHAR ROM_Buffer[BUFFER_SIZE];

//#define R98_PCICONFIG_START           ((PULONG)(0x18ca8800 | KSEG1_BASE))

extern KSPIN_LOCK          HalpPCIConfigLock;
BOOLEAN HalpInitX86Emulator(
  VOID)

{
    ULONG  ROM_size = 0;
    PHYSICAL_ADDRESS PhysAddr;
    UCHAR BaseClass, SubClass, ProgIf;// M001
    USHORT Cmd,SetCmd, VendorID, DeviceID, Slot; // M002
    PUCHAR ROM_Ptr, ROM_Shadow;
    ULONG i;
    ULONG r;
    USHORT PciDataOffset;  // M001
    PCI_SLOT_NUMBER PciSlot;
    UCHAR header;
    KIRQL            Irql;
    PhysAddr.HighPart = 0x00000000;


#if 1
    KeInitializeSpinLock (&HalpPCIConfigLock);
    //kuku
    KeRaiseIrql (PROFILE_LEVEL, &Irql);
    KiAcquireSpinLock (&HalpPCIConfigLock);



#if 0 //tmp 707  // M001
  // First Check ISA BIOS.Becase PCEB 0-1M Positive Decode So
  // I Can See ROM Image. 
  // Create a mapping to ISA memory space, unless one already exists
  //

  HalpIoMemoryBase=   (PVOID)0x40000000; 
  ROM_size = 0xD0000;   // Map to end of option ROM space

  //
  // Look for ISA option video ROM signature
  //
  ROM_Ptr = (PUCHAR) HalpIoMemoryBase + 0xC0000;
  HalpRomBase = ROM_Ptr;
  if (*ROM_Ptr == 0x55 && *(ROM_Ptr+1) == 0xAA) {
        //
        // Copy ROM to RAM.  PCI Spec says you can't execute from ROM.
        // ROM and video RAM sometimes can't co-exist.
        //
        ROM_Length = *(ROM_Ptr+2) << 9;
        if (ROM_Length <= BUFFER_SIZE) {
          for (i=0; i<ROM_Length; i++)
            ROM_Buffer[i] = *ROM_Ptr++;
        }
#if defined(_X86_DBG_)
        DbgPrint("\n EISA ROM BIOS Found \n");  //DBGDBG   
#endif // _X86_DBG_
        HalpRomBase = (PUCHAR) ROM_Buffer;
        HalpIoControlBase= (PVOID)0x403f0000;

        KiReleaseSpinLock (&HalpPCIConfigLock);
        KeLowerIrql (Irql);

        return TRUE;

  }
#endif

  //
  // Scan PCI slots for video BIOS ROMs, except 3 PCI "slots" on motherboard
  //
  // Slot 0: Hurrucane (host bridge)
  // Slot 1: Typhoon (Internal-bus bridge)
  // Slot 2: PCI-EISA bridge
  //
  for (Slot = 3; Slot < 6; Slot++) {
#if defined(_X86_DBG_)
    DbgPrint("\n PCI SLot Number=%x\n",Slot);  //DBGDBG   
#endif // _X86_DBG_
    //
    // Create a mapping to PCI configuration space
    //

    PciSlot.u.bits.FunctionNumber = 0;
    PciSlot.u.bits.DeviceNumber = Slot ;

    //
    // Read Vendor ID and check if slot is empty
    //

    HalpReadPCIConfigUshortByOffset(PciSlot,&VendorID,FIELD_OFFSET (PCI_COMMON_CONFIG, VendorID));

#if defined(_X86_DBG_)
DbgPrint("\n Vendor ID=%x\n",VendorID);  //DBGDBG                            
#endif // _X86_DBG_

    if (VendorID == 0xFFFF){
        continue;       // Slot is empty; go to next slot
    }

// M002 +++
    //
    // Read Device ID and check if slot is empty
    //

    HalpReadPCIConfigUshortByOffset(PciSlot,&DeviceID,FIELD_OFFSET (PCI_COMMON_CONFIG, DeviceID));

    //
    // Check for GLINT or DEC-GA board.
    //

    if ( (VendorID == 0x3d3d && DeviceID == 0x0001) ||
	(VendorID == 0x1011 && DeviceID == 0x0004) ) {
	continue;
    }
// M002 ---    


// M001 +++
    //
    //	Check Base Class Code
    //
    HalpReadPCIConfigUcharByOffset(PciSlot,&BaseClass,FIELD_OFFSET (PCI_COMMON_CONFIG, BaseClass));

#if defined(_X86_DBG_)
    DbgPrint("\n BaseClass =%x\n",BaseClass); //DBGDBG
#endif // _X86_DBG_
     
    //
    //	Check Sub Class Code
    //
    HalpReadPCIConfigUcharByOffset(PciSlot,&SubClass,FIELD_OFFSET (PCI_COMMON_CONFIG, SubClass));

#if defined(_X86_DBG_)
    DbgPrint("\n SubClass =%x\n",SubClass); //DBGDBG
#endif // _X86_DBG_

    //
    //	Check Proglamming Interface
    //
    HalpReadPCIConfigUcharByOffset(PciSlot,&ProgIf,FIELD_OFFSET (PCI_COMMON_CONFIG, ProgIf));

#if defined(_X86_DBG_)
    DbgPrint("\n ProgIf =%x\n",ProgIf); //DBGDBG
#endif // _X86_DBG_

    //
    // check if video card
    //
    if ( ( (BaseClass == 0) && (SubClass == 1) && (ProgIf == 0) ) || //S003
	 ( (BaseClass == 3) && (SubClass == 0) && (ProgIf == 0) ) ||
	 ( (BaseClass == 3) && (SubClass == 1) && (ProgIf == 0) ) ||
	 ( (BaseClass == 3) && (SubClass == 0x80) && (ProgIf == 0) ) ) {
#if defined(_X86_DBG_)
	DbgPrint("\n This is Video card \n");
#endif // _X86_DBG_
    } else {
#if defined(_X86_DBG_)
	DbgPrint("\n This is not Video card \n");
#endif // _X86_DBG_
	continue;
    }
// M001 ---

    //
    // Get size of ROM
    //

    ROM_size=0xFFFFFFFF;

#if defined(_X86_DBG_)
    DbgPrint("ROM size config offset = %x\n",FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));
#endif // _X86_DBG_
    HalpWritePCIConfigUlongByOffset(PciSlot,&ROM_size,FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));

    HalpReadPCIConfigUlongByOffset(PciSlot,&ROM_size,FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));


#if defined(_X86_DBG_)
    DbgPrint("\nROM_Size = %0x\n",ROM_size);
#endif // _X86_DBG_

    if ((ROM_size != 0xFFFFFFFF) && (ROM_size != 0)) {

 
      ROM_size = 0xD0000;       // Map to end of option ROM space

      //
      // Set Expansion ROM Base Address & enable ROM
      //

      PhysAddr.LowPart = 0x000C0000 | PCI_ROMADDRESS_ENABLED;

      HalpWritePCIConfigUlongByOffset(PciSlot,&(PhysAddr.LowPart),FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));

      //
      // Enable Memory & I/O spaces in command register
      //

      HalpReadPCIConfigUshortByOffset(PciSlot,&Cmd,FIELD_OFFSET (PCI_COMMON_CONFIG, Command));

#if defined(_X86_DBG_)
      DbgPrint("\nREAD CMD=%0x\n",Cmd);
#endif // _X86_DBG_

      SetCmd = Cmd|0x3;

      HalpWritePCIConfigUshortByOffset(PciSlot,&SetCmd,FIELD_OFFSET (PCI_COMMON_CONFIG, Command));

      // Map Phys C0000000-C00D0000
      // Create a mapping to the PCI memory space
      //
      PhysAddr.HighPart = 1;
      PhysAddr.LowPart=0;

#if 1


      HalpIoMemoryBase=   (PVOID)0x40000000; 
#else
      HalpIoMemoryBase = MmMapIoSpace(PhysAddr, ROM_size,FALSE);
      if (HalpIoMemoryBase == NULL) {
#if defined(_X86_DBG_)
        DbgPrint("\nCan't create mapping to PCI memory space\n");
#endif // _X86_DBG_
        KiReleaseSpinLock (&HalpPCIConfigLock);
        KeLowerIrql (Irql);
        return FALSE;
      }
#endif
      //
      // Look for PCI option video ROM signature
      //
      HalpRomBase = ROM_Ptr = (PUCHAR) HalpIoMemoryBase + 0xC0000;
#if defined(_X86_DBG_)
      DbgPrint("\nHalpRomBase=%x\n",HalpRomBase);
#endif // _X86_DBG_
      if (*ROM_Ptr == 0x55 && *(ROM_Ptr+1) == 0xAA) {
        //
        // Copy ROM to RAM.  PCI Spec says you can't execute from ROM.
        // Sometimes option ROM and video RAM can't co-exist.
        //
        ROM_Length = *(ROM_Ptr+2) << 9;
        if (ROM_Length <= BUFFER_SIZE) {
          for (i=0; i<ROM_Length; i++)
            ROM_Buffer[i] = *ROM_Ptr++;


          HalpRomBase = (PUCHAR) ROM_Buffer;
#if defined(_X86_DBG_)
          DbgPrint("\nROM Short HalpRomBase=%x\n",HalpRomBase);
#endif // _X86_DBG_
          
        }

#if 0 // M002
// M001 +++
	//
	// check rom code is INTEL BASE
	//

	PciDataOffset = *(PUSHORT)(0x400c0000 + 0x18);
#if defined(_X86_DBG_)
    DbgPrint("PciDataOffset = %x\n",PciDataOffset);
#endif // _X86_DBG_

	if ( *(PUCHAR)(0x400c0000 + (ULONG)PciDataOffset + 0x14) == 0 ) {
//        DbgPrint("check PCI rom\n");
//        DbgBreakPoint();
#if defined(_X86_DBG_)
	    DbgPrint("\n This is intel base rom \n");
#endif // _X86_DBG_
	} else {
#if defined(_X86_DBG_)
	    DbgPrint("\n This is not intel  base rom \n");
#endif // _X86_DBG_

	    //
	    // Disable Rom address
	    //

	    PhysAddr.LowPart = 0x000C0000;
	    HalpWritePCIConfigUlongByOffset(PciSlot,&(PhysAddr.LowPart),FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));

	    continue;
	}
// M001 ---
#endif // 0 // M002

	//
        // Io Map.
        //
        HalpIoControlBase= (PVOID)0x403f0000;

#if 0 // M001---
      PhysAddr.LowPart = 0x000C0000;
      HalpWritePCIConfigUlongByOffset(PciSlot,&(PhysAddr.LowPart),FIELD_OFFSET (PCI_COMMON_CONFIG, u.type0.ROMBaseAddress));
#endif // M001---

#if 0  //706  
        //      Found PCI VIDEO ROM.
        //              1.Map ISA Memory Space 
        //              2.
#if defined(_X86_DBG_)
        DbgPrint("\nFound PCI ROM BIOS\n");
#endif // _X86_DBG_


        //  0: rom enable so do  PCI
        //  1: rom disable so do EISA vga

        HalpWritePCIConfigUshortByOffset(PciSlot,&Cmd,FIELD_OFFSET (PCI_COMMON_CONFIG, Command));

#endif

         KiReleaseSpinLock (&HalpPCIConfigLock);
         KeLowerIrql (Irql);

         return TRUE;    // Exit slot scan after finding 1st option ROM
      }
//      MmUnmapIoSpace (      HalpIoMemoryBase, ROM_size);

      // Not Found So Reset!!.
      // Delete mapping to PCI memory space


#if 1  //706  
        //      Found PCI VIDEO ROM.
        //              1.Map ISA Memory Space 
        //              2.
#if defined(_X86_DBG_)
        DbgPrint("\nFound PCI ROM BIOS\n");
#endif // _X86_DBG_


      //  0: rom enable so do  PCI
      //  1: rom disable so do EISA vga

      HalpWritePCIConfigUshortByOffset(PciSlot,&Cmd,FIELD_OFFSET (PCI_COMMON_CONFIG, Command));
      
#endif

    } // end of if clause
#if defined(_X86_DBG_)
    DbgPrint("\n ROM SIZE invalid\n");  //DBGDBG   
#endif // _X86_DBG_
  } // end of for loop
#else
//      ROM_size = 0xD0000;     // Map to end of option ROM space
#endif


    KiReleaseSpinLock (&HalpPCIConfigLock);
    KeLowerIrql (Irql);

#if 1 //tmp 707 // M001
  // No PCI BIOS SO Search ISA BIOS.
  // Create a mapping to ISA memory space, unless one already exists
  //

  HalpIoMemoryBase=   (PULONG)0x40000000; 
  ROM_size = 0xD0000;   // Map to end of option ROM space

  //
  // Look for ISA option video ROM signature
  //
  ROM_Ptr = (PUCHAR) HalpIoMemoryBase + 0xC0000;
  HalpRomBase = ROM_Ptr;
  if (*ROM_Ptr == 0x55 && *(ROM_Ptr+1) == 0xAA) {
//        DbgPrint("check PCI rom\n");
//        DbgBreakPoint();
        //
        // Copy ROM to RAM.  PCI Spec says you can't execute from ROM.
        // ROM and video RAM sometimes can't co-exist.
        //
        ROM_Length = *(ROM_Ptr+2) << 9;
        if (ROM_Length <= BUFFER_SIZE) {
          for (i=0; i<ROM_Length; i++)
            ROM_Buffer[i] = *ROM_Ptr++;
        }
#if defined(_X86_DBG_)
        DbgPrint("\n EISA ROM BIOS Found \n");  //DBGDBG   
#endif // _X86_DBG_
        HalpRomBase = (PUCHAR) ROM_Buffer;
        HalpIoControlBase= (PVOID)0x403f0000;
        return TRUE;
  }
#endif
  // 
  // No video option ROM was found.  Delete mapping to PCI memory space.
  //
#if defined(_X86_DBG_)
  DbgPrint("\n 55AA BIOS Not \n");  //DBGDBG   
#endif // _X86_DBG_
  return FALSE;
}

//--------------------

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.

--*/

{

#if defined(USE_BIOS_EMULATOR)

    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) && (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,
                                HalpIoControlBase,
                                HalpIoMemoryBase) != 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;

#else

    return FALSE;

#endif

}

BOOLEAN
HalpInitializeX86DisplayAdapter(
    VOID
    )

/*++

Routine Description:

    This function initializes a display adapter using the x86 bios emulator.

Arguments:

    None.

Return Value:

    None.

--*/

{

#if defined(USE_BIOS_EMULATOR)

    //
    // If EISA I/O Ports or EISA memory could not be mapped, then don't
    // attempt to initialize the display adapter.
    //

    if (!HalpInitX86Emulator())
        return FALSE;

    if (HalpIoControlBase == NULL || HalpIoMemoryBase == NULL) {
        return FALSE;
    }

    //
    // Initialize the x86 bios emulator.
    //

    x86BiosInitializeBios(HalpIoControlBase, HalpIoMemoryBase);
    HalpX86BiosInitialized = TRUE;

    //
    // Attempt to initialize the display adapter by executing its ROM bios
    // code. The standard ROM bios code address for PC video adapters is
    // 0xC000:0000 on the ISA bus.
    //

    if (x86BiosInitializeAdapter(0xc0000, NULL, HalpIoControlBase, HalpIoMemoryBase) != XM_SUCCESS) {
        HalpEnableInt10Calls = FALSE;
        return FALSE;
    }
    HalpEnableInt10Calls = TRUE;

#endif

    return TRUE;
}

VOID
HalpResetX86DisplayAdapter(
    VOID
    )

/*++

Routine Description:

    This function resets a display adapter using the x86 bios emulator.

Arguments:

    None.

Return Value:

    None.

--*/

{

#if defined(USE_BIOS_EMULATOR)

    XM86_CONTEXT Context;

    //
    // Initialize the x86 bios context and make the INT 10 call to initialize
    // the display adapter to 80x25 color text mode.
    //

    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);

#endif

    return;
}


//
// This code came from ..\..\x86new\x86bios.c
//
#define LOW_MEMORY_SIZE 0x800
extern UCHAR x86BiosLowMemory[LOW_MEMORY_SIZE + 3];
extern ULONG x86BiosScratchMemory;
extern ULONG x86BiosIoMemory;
extern ULONG x86BiosIoSpace;


PVOID
x86BiosTranslateAddress (
    IN USHORT Segment,
    IN USHORT Offset
    )

/*++

Routine Description:

    This translates a segment/offset address into a memory address.

Arguments:

    Segment - Supplies the segment register value.

    Offset - Supplies the offset within segment.

Return Value:

    The memory address of the translated segment/offset pair is
    returned as the function value.

--*/

{

    ULONG Value;

    //
    // Compute the logical memory address and case on high hex digit of
    // the resultant address.
    //

    Value = Offset + (Segment << 4);
    Offset = (USHORT)(Value & 0xffff);
    Value &= 0xf0000;
    switch ((Value >> 16) & 0xf) {

        //
        // Interrupt vector/stack space.
        //

    case 0x0:
        if (Offset > LOW_MEMORY_SIZE) {
            x86BiosScratchMemory = 0;
            return (PVOID)&x86BiosScratchMemory;

        } else {
            return (PVOID)(&x86BiosLowMemory[0] + Offset);
        }

        //
        // The memory range from 0x10000 to 0x9ffff reads as zero
        // and writes are ignored.
        //

    case 0x1:
    case 0x2:
    case 0x3:
    case 0x4:
    case 0x5:
    case 0x6:
    case 0x7:
    case 0x8:
    case 0x9:
        x86BiosScratchMemory = 0;
        return (PVOID)&x86BiosScratchMemory;

        //
        // The memory range from 0xa0000 to 0xdffff maps to I/O memory.
        //

    case 0xa:
    case 0xb:
        return (PVOID)(x86BiosIoMemory + Offset + Value);

    case 0xc:
    case 0xd:
        return (PVOID)(HalpRomBase + Offset);

        //
        // The memory range from 0x10000 to 0x9ffff reads as zero
        // and writes are ignored.
        //

    case 0xe:
    case 0xf:
        x86BiosScratchMemory = 0;
        return (PVOID)&x86BiosScratchMemory;
    }

    // NOT REACHED - NOT EXECUTED - Prevents Compiler Warning.
    return (PVOID)NULL;
}


VOID HalpCopyROMs(VOID) 
{
ULONG i;
PUCHAR ROM_Shadow;

  if (ROM_Buffer[0] == 0x55 && ROM_Buffer[1] == 0xAA) {
    HalpRomBase = ROM_Shadow = ExAllocatePool(NonPagedPool, ROM_Length);
#if defined(_X86_DBG_)
    DbgPrint("HalpRomBase=%0x\n",HalpRomBase);
#endif // _X86_DBG_
    for (i=0; i<ROM_Length; i++) {
      *ROM_Shadow++ = ROM_Buffer[i];
    }
  }
}


/****Include File x86new\x86bios.c Here - except the routine x86BiosTranslateAddress.  ****/

/*++

Copyright (c) 1994  Microsoft Corporation

Module Name:

    x86bios.c

Abstract:

    This module implements supplies the HAL interface to the 386/486
    real mode emulator for the purpose of emulating BIOS calls..

Author:

    David N. Cutler (davec) 13-Nov-1994

Environment:

    Kernel mode only.

Revision History:

--*/

#include "nthal.h"
#include "hal.h"
#include "xm86.h"
#include "x86new.h"

//
// Define the size of low memory.
//

#define LOW_MEMORY_SIZE 0x800
//
// Define storage for low emulated memory.
//

UCHAR x86BiosLowMemory[LOW_MEMORY_SIZE + 3];
ULONG x86BiosScratchMemory;

//
// Define storage to capture the base address of I/O space and the
// base address of I/O memory space.
//

ULONG x86BiosIoMemory;
ULONG x86BiosIoSpace;

//
// Define BIOS initialized state.
//

BOOLEAN x86BiosInitialized = FALSE;

ULONG
x86BiosReadIoSpace (
    IN XM_OPERATION_DATATYPE DataType,
    IN USHORT PortNumber
    )

/*++

Routine Description:

    This function reads from emulated I/O space.

Arguments:

    DataType - Supplies the datatype for the read operation.

    PortNumber - Supplies the port number in I/O space to read from.

Return Value:

    The value read from I/O space is returned as the function value.

    N.B. If an aligned operation is specified, then the individual
        bytes are read from the specified port one at a time and
        assembled into the specified datatype.

--*/

{

    ULONG Result;

    union {
        PUCHAR Byte;
        PUSHORT Word;
        PULONG Long;
    } u;

    //
    // Compute port address and read port.
    //

    u.Long = (PULONG)(x86BiosIoSpace + PortNumber);
//    DbgPrint("read port %x translate %x\n",PortNumber,u.Long);
    
    if (DataType == BYTE_DATA) {
        Result = READ_REGISTER_UCHAR(u.Byte);

    } else if (DataType == LONG_DATA) {
        if (((ULONG)u.Long & 0x3) != 0) {
            Result = (READ_REGISTER_UCHAR(u.Byte + 0)) |
                     (READ_REGISTER_UCHAR(u.Byte + 1) << 8) |
                     (READ_REGISTER_UCHAR(u.Byte + 2) << 16) |
                     (READ_REGISTER_UCHAR(u.Byte + 3) << 24);

        } else {
            Result = READ_REGISTER_ULONG(u.Long);
        }

    } else {
        if (((ULONG)u.Word & 0x1) != 0) {
            Result = (READ_REGISTER_UCHAR(u.Byte + 0)) |
                     (READ_REGISTER_UCHAR(u.Byte + 1) << 8);

        } else {
            Result = READ_REGISTER_USHORT(u.Word);
        }
    }

    return Result;
}

VOID
x86BiosWriteIoSpace (
    IN XM_OPERATION_DATATYPE DataType,
    IN USHORT PortNumber,
    IN ULONG Value
    )

/*++

Routine Description:

    This function write to emulated I/O space.

    N.B. If an aligned operation is specified, then the individual
        bytes are written to the specified port one at a time.

Arguments:

    DataType - Supplies the datatype for the write operation.

    PortNumber - Supplies the port number in I/O space to write to.

    Value - Supplies the value to write.

Return Value:

    None.

--*/

{

    union {
        PUCHAR Byte;
        PUSHORT Word;
        PULONG Long;
    } u;

    //
    // Compute port address and read port.
    //

    u.Long = (PULONG)(x86BiosIoSpace + PortNumber);
//    DbgPrint("write port %x translate %x\n",PortNumber,u.Long);
    if (DataType == BYTE_DATA) {
        WRITE_REGISTER_UCHAR(u.Byte, (UCHAR)Value);

    } else if (DataType == LONG_DATA) {
        if (((ULONG)u.Long & 0x3) != 0) {
            WRITE_REGISTER_UCHAR(u.Byte + 0, (UCHAR)(Value));
            WRITE_REGISTER_UCHAR(u.Byte + 1, (UCHAR)(Value >> 8));
            WRITE_REGISTER_UCHAR(u.Byte + 2, (UCHAR)(Value >> 16));
            WRITE_REGISTER_UCHAR(u.Byte + 3, (UCHAR)(Value >> 24));

        } else {
            WRITE_REGISTER_ULONG(u.Long, Value);
        }

    } else {
        if (((ULONG)u.Word & 0x1) != 0) {
            WRITE_REGISTER_UCHAR(u.Byte + 0, (UCHAR)(Value));
            WRITE_REGISTER_UCHAR(u.Byte + 1, (UCHAR)(Value >> 8));

        } else {
            WRITE_REGISTER_USHORT(u.Word, (USHORT)Value);
        }
    }

    return;
}

VOID
x86BiosInitializeBios (
    IN PVOID BiosIoSpace,
    IN PVOID BiosIoMemory
    )

/*++

Routine Description:

    This function initializes x86 BIOS emulation.

Arguments:

    BiosIoSpace - Supplies the base address of the I/O space to be used
        for BIOS emulation.

    BiosIoMemory - Supplies the base address of the I/O memory to be
        used for BIOS emulation.

Return Value:

    None.

--*/

{

    //
    // Zero low memory.
    //

    memset(&x86BiosLowMemory, 0, LOW_MEMORY_SIZE);

    //
    // Save base address of I/O memory and I/O space.
    //

    x86BiosIoSpace = (ULONG)BiosIoSpace;
    x86BiosIoMemory = (ULONG)BiosIoMemory;

    //
    // Initialize the emulator and the BIOS.
    //

    XmInitializeEmulator(0,
                         LOW_MEMORY_SIZE,
                         x86BiosReadIoSpace,
                         x86BiosWriteIoSpace,
                         x86BiosTranslateAddress);

#if defined(_X86_DBG_)
    DbgPrint("\n EMU INIT \n");  //DBGDBG   
#endif // _X86_DBG_
    x86BiosInitialized = TRUE;
    return;
}

XM_STATUS
x86BiosExecuteInterrupt (
    IN UCHAR Number,
    IN OUT PXM86_CONTEXT Context,
    IN PVOID BiosIoSpace OPTIONAL,
    IN PVOID BiosIoMemory OPTIONAL
    )

/*++

Routine Description:

    This function executes an interrupt by calling the x86 emulator.

Arguments:

    Number - Supplies the number of the interrupt that is to be emulated.

    Context - Supplies a pointer to an x86 context structure.

Return Value:

    The emulation completion status.

--*/

{

    XM_STATUS Status;

    //
    // If a new base address is specified, then set the appropriate base.
    //

    if (BiosIoSpace != NULL) {
        x86BiosIoSpace = (ULONG)BiosIoSpace;
    }

    if (BiosIoMemory != NULL) {
        x86BiosIoMemory = (ULONG)BiosIoMemory;
    }

    //
    // Execute the specified interrupt.
    //

    Status = XmEmulateInterrupt(Number, Context);
    if (Status != XM_SUCCESS) {
#if defined(_X86_DBG_)
        DbgPrint("HAL: Interrupt emulation failed, status %lx\n", Status);
#endif // _X86_DBG_
    }

    return Status;
}

XM_STATUS
x86BiosInitializeAdapter (
    IN ULONG Adapter,
    IN OUT PXM86_CONTEXT Context OPTIONAL,
    IN PVOID BiosIoSpace OPTIONAL,
    IN PVOID BiosIoMemory OPTIONAL
    )

/*++

Routine Description:

    This function initializes the adapter whose BIOS starts at the
    specified 20-bit address.

Arguments:

    Adpater - Supplies the 20-bit address of the BIOS for the adapter
        to be initialized.

Return Value:

    The emulation completion status.

--*/

{

    PUCHAR Byte;
    XM86_CONTEXT State;
    USHORT Offset;
    USHORT Segment;
    XM_STATUS Status;

#if defined(_X86_DBG_)
    DbgPrint("\n BIOS INIT \n");  //DBGDBG   
#endif // _X86_DBG_
    //
    // If BIOS emulation has not been initialized, then return an error.
    //

    if (x86BiosInitialized == FALSE) {
        return XM_EMULATOR_NOT_INITIALIZED;
    }

    //
    // If an emulator context is not specified, then use a default
    // context.
    //

    if (ARGUMENT_PRESENT(Context) == FALSE) {
        State.Eax = 0;
        State.Ecx = 0;
        State.Edx = 0;
        State.Ebx = 0;
        State.Ebp = 0;
        State.Esi = 0;
        State.Edi = 0;
        Context = &State;
    }

    //
    // If a new base address is specified, then set the appropriate base.
    //

    if (BiosIoSpace != NULL) {
        x86BiosIoSpace = (ULONG)BiosIoSpace;
    }

    if (BiosIoMemory != NULL) {
        x86BiosIoMemory = (ULONG)BiosIoMemory;
    }

    //
    // If the specified adpater is not BIOS code, then return an error.
    //

    Segment = (USHORT)((Adapter >> 4) & 0xf000);
    Offset = (USHORT)(Adapter & 0xffff);
    Byte = (PUCHAR)x86BiosTranslateAddress(Segment, Offset);
    if ((*Byte++ != 0x55) || (*Byte != 0xaa)) {
        return XM_ILLEGAL_CODE_SEGMENT;
    }

    //
    // Call the BIOS code to initialize the specified adapter.
    //

    Adapter += 3;
    Segment = (USHORT)((Adapter >> 4) & 0xf000);
    Offset = (USHORT)(Adapter & 0xffff);
#if defined(_X86_DBG_)
    DbgPrint("\n Emcall BIOS start \n");  //DBGDBG   
#endif // _X86_DBG_
    Status = XmEmulateFarCall(Segment, Offset, Context);
#if defined(_X86_DBG_)
    DbgPrint("\n Emcall BIOS End \n");  //DBGDBG   
#endif // _X86_DBG_
    if (Status != XM_SUCCESS) {
#if defined(_X86_DBG_)
        DbgPrint("HAL: Adapter initialization falied, status %lx\n", Status);
#endif // _X86_DBG_
    }

    return Status;
}