/** @file
 Implement the Chipset Servcie IHISI OemExtra Data subfunction for this driver.

;***************************************************************************
;* Copyright (c) 2017 - 2021, Insyde Software Corp. All Rights Reserved.
;*
;* You may not reproduce, distribute, publish, display, perform, modify, adapt,
;* transmit, broadcast, present, recite, release, license or otherwise exploit
;* any part of this publication in any form, by any means, without the prior
;* written permission of Insyde Software Corporation.
;*
;******************************************************************************
*/

#include <Uefi.h>
#include <H2OIhisi.h>
#include "BiosGuard.h"
#include <CpuRegs.h>
#include "IndustryStandard/Oa3_0.h"
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/SmmChipsetSvcLib.h>
#include <Library/SmmOemSvcChipsetLib.h>
#include <Library/SmmServicesTableLib.h>
#include <Library/BaseOemSvcKernelLib.h>
#include <Protocol/BiosGuard.h>
#include <Protocol/H2OIhisi.h>
#include <Protocol/SmmFwBlockService.h>
#include <Protocol/SmmVariable.h>
#include <CsSvcIhisiOemExtraDataCommunication.h>
#include <CsSvcIhisiFbts.h>
#include <Register/CommonMsr.h>
#include <Library/MsrFruLib.h>
#include <IndustryStandard/Oa3_0.h>
#include <Library/SmmHeciLib.h>

extern BOOLEAN                               mFlashME;
extern UINTN                                 mWriteSize;
extern H2O_IHISI_PROTOCOL                   *mH2OIhisi;
extern EFI_SMM_FW_BLOCK_SERVICE_PROTOCOL    *mSmmFwBlockService;
extern BIOSGUARD_PROTOCOL                   *mBiosGuardProtocol;
extern EFI_PHYSICAL_ADDRESS                 mBiosGuardMemAddress;
extern UINTN                                mBiosGuardMemSize;
extern EFI_SMM_VARIABLE_PROTOCOL            *mSmmVariable;
static EFI_GUID                             gMsdmAddressGuid = MEMORY_ADDRESS_FOR_MSDM_GUID;

// These Offset should check BiosGuard Script, which described the Destination Flash Address and DataSize, Please reference GenBiosGuardHdr.h
#define BGSL_DST_TYPE_OFFSET       0x03
#define BGSL_SIZE_OFFSET           0x05
#define BGSL_SPI_DST_ADDR_OFFSET   0x07 


/**
  TURE  -- Platform Pfat/BiosGuard feature enabling
  FALSE -- Platform Pfat/BiosGuard feature disabling
**/
BOOLEAN
IsBiosGuardSupport (
  VOID
  )
{
  MSR_PLAT_FRMW_PROT_CTRL_REGISTER          PlatFrmwProtCtrl;

  if (!MsrIsPfatEnabled()) {
    //
    // Cpu does not support Pfat/BiosGuard Feature.
    //
    return FALSE;
  }

  PlatFrmwProtCtrl.Uint64 = AsmReadMsr64 (MSR_PLAT_FRMW_PROT_CTRL);
  if (PlatFrmwProtCtrl.Bits.PfatEnable == 1) {
    //
    // Pfat/BiosGuard feature enabled.
    //
    return TRUE;
  }

  return FALSE;
}

/**
  TURE  -- Platform FlashWearOut Set
  FALSE -- Platform FlashWearOut Un-set
**/
BOOLEAN
IsFlashWearOutSet (
  VOID
  )
{
  UINT64          PlatformBiosInfo;
  UINTN           DataSize;
  EFI_STATUS      Status;

  DataSize = sizeof (UINT64);
  Status = mSmmVariable->SmmGetVariable (
                           L"BiosInfoFlagData",
                           &gBiosInfoFlagGuid,
                           NULL,
                           &DataSize,
                           &PlatformBiosInfo
                           );
  if (!EFI_ERROR(Status) && PlatformBiosInfo & BIT0) {
    return TRUE;
  }
  return FALSE;
}

STATIC
BOOLEAN
MsdmExist (
  VOID
  )
{
  EFI_STATUS                       Status;
  UINTN                            DataSize;
  BOOLEAN                          MsdmExist;
  UINTN                            RomBaseAddress;
  EFI_ACPI_MSDM_DATA_STRUCTURE    *MsdmData;
  UINT8                           *VarDataBuffer;

  MsdmData = NULL;
  MsdmExist = FALSE;
  VarDataBuffer = NULL;

  if (IsBiosGuardSupport () && IsFlashWearOutSet()) {
    DataSize = (UINTN) FixedPcdGet32 (PcdFlashNvStorageMsdmDataSize);
    Status = gSmst->SmmAllocatePool (
                      EfiRuntimeServicesData,
                      DataSize,
                      (VOID **)&VarDataBuffer
                      );
    Status = mSmmVariable->SmmGetVariable (
                             L"MsdmUpdate",
                             &gMsdmAddressGuid,
                             NULL,
                             &DataSize,
                             VarDataBuffer
                             );
  
    if (!EFI_ERROR (Status)){
      Status = mSmmVariable->SmmSetVariable (
                               L"MsdmUpdate",
                               &gMsdmAddressGuid,
                               EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,
                               0,
                               NULL
                               );
    }
  }

  DataSize = sizeof (EFI_ACPI_MSDM_DATA_STRUCTURE);
  RomBaseAddress = (UINTN) FixedPcdGet32 (PcdFlashNvStorageMsdmDataBase);

  Status = gSmst->SmmAllocatePool (
                    EfiRuntimeServicesData,
                    DataSize,
                    (VOID **)&MsdmData
                    );
  if (EFI_ERROR (Status)) {
    goto Done;
  }
  *(mSmmFwBlockService->FlashMode) = SMM_FW_DEFAULT_MODE;
  Status = mSmmFwBlockService->Read (
                                 mSmmFwBlockService,
                                 RomBaseAddress,
                                 0,
                                 &DataSize,
                                 (UINT8*) MsdmData
                                 );
  if (EFI_ERROR (Status)) {
    goto Done;
  }

  if ((MsdmData->MsdmVersion == 0xFFFFFFFF) &&
      (MsdmData->MdsmDataType == 0xFFFFFFFF) &&
      (MsdmData->MsdmDataLength == 0xFFFFFFFF)) {
    goto Done;
  }

  MsdmExist = TRUE;

Done:
  if (MsdmData != NULL) {
    gSmst->SmmFreePool (MsdmData);
  }
  return MsdmExist;
}

/**
  AH=41h, OEM Extra Data Communication type 50h to read/write OA3.0.

  @param[in]  ApCommDataBuffer   Pointer to AP communication data buffer.
  @param[out] BiosCommDataBuffer Pointer to BIOS communication data buffer.

  @retval EFI_SUCCESS  Read or write OA3.0 successful.
**/
EFI_STATUS
Oa30ReadWriteFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{
  UINT32                      MsdmDataSize;

  MsdmDataSize = sizeof (EFI_ACPI_MSDM_DATA_STRUCTURE);
  switch (ApCommDataBuffer->DataSize) {

  case OemExtraReportReadSize:
    BiosCommDataBuffer->Signature        = BIOS_COMMUNICATION_SIGNATURE;
    BiosCommDataBuffer->StructureSize    = sizeof (BIOS_COMMUNICATION_DATA_TABLE);
    BiosCommDataBuffer->BlockSize        = OemExtraBlockSize4k;
    BiosCommDataBuffer->DataSize         = OemExtraReportReadSize;
    BiosCommDataBuffer->PhysicalDataSize = MsdmDataSize;
    break;

  case OemExtraSkipSizeCheck:
    BiosCommDataBuffer->Signature        = BIOS_COMMUNICATION_SIGNATURE;
    BiosCommDataBuffer->StructureSize    = sizeof (BIOS_COMMUNICATION_DATA_TABLE);
    BiosCommDataBuffer->BlockSize        = OemExtraBlockSize4k;
    BiosCommDataBuffer->DataSize         = OemExtraSkipSizeCheck;   //Don't care
    BiosCommDataBuffer->PhysicalDataSize = 0x00;                   //Don't care
    break;

  case OemExtraReportWriteSize:
    BiosCommDataBuffer->Signature        = BIOS_COMMUNICATION_SIGNATURE;
    BiosCommDataBuffer->StructureSize    = sizeof (BIOS_COMMUNICATION_DATA_TABLE);
    BiosCommDataBuffer->BlockSize        = OemExtraBlockSize4k;
    BiosCommDataBuffer->DataSize         = OemExtraReportWriteSize;
    BiosCommDataBuffer->PhysicalDataSize = MsdmDataSize;   //bin size
    break;

  default:
    break;
  }

  if (!MsdmExist ()) {
    BiosCommDataBuffer->ErrorReturn    = (BiosCommDataBuffer->ErrorReturn | ERROR_RETURE_OA30_NOT_EXIST);
  }

  return EFI_SUCCESS;
}

/**
  AH=41h, OEM Extra Data Communication type 51h to erase OA3.0 (reset to default).

  @param[in]  ApCommDataBuffer   Pointer to AP communication data buffer.
  @param[out] BiosCommDataBuffer Pointer to BIOS communication data buffer.

  @retval EFI_SUCCESS  Erase OA3.0 successful.
**/
EFI_STATUS
Oa30EraseFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{
  EFI_STATUS                   Status;
  EFI_STATUS                   OemSvcStatus;
  UINT8                        LoopCount;
  UINTN                        RomBaseAddress;
  UINTN                        EraseSize;
  UINT8                        Erase;

  RomBaseAddress = (UINTN) FixedPcdGet32 (PcdFlashNvStorageMsdmDataBase);
  LoopCount = 0;
  EraseSize = 0x1000;
  Status = EFI_SUCCESS;

  if (!MsdmExist ()) {
    BiosCommDataBuffer->ErrorReturn    = (BiosCommDataBuffer->ErrorReturn | ERROR_RETURE_OA30_NOT_EXIST);
    goto Done;
  }

  if (PcdGetBool (PcdEcSharedFlashSupported)) {
    DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices Call: OemSvcEcIdle \n"));
    OemSvcStatus = OemSvcEcIdle (TRUE);
    DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices OemSvcEcIdle Status: %r\n", OemSvcStatus));
  }
  
  Status = EFI_UNSUPPORTED;
  if (IsBiosGuardSupport () && IsFlashWearOutSet()) {
    Erase = 1;
    Status = mSmmVariable->SmmSetVariable (
                             L"MsdmErase",
                             &gMsdmAddressGuid,
                             EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,
                             sizeof(UINT8),
                             &Erase
                             );
  } else {
    *(mSmmFwBlockService->FlashMode) = SMM_FW_DEFAULT_MODE;
    while ((EFI_ERROR (Status)) && (LoopCount < 100)) {
      Status = mSmmFwBlockService->EraseBlocks (
                                     mSmmFwBlockService,
                                     RomBaseAddress,
                                     &EraseSize
                                     );
      LoopCount++;
    }
  }

  if (PcdGetBool (PcdEcSharedFlashSupported)) {
    DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices Call: OemSvcEcIdle \n"));
    OemSvcStatus = OemSvcEcIdle (FALSE);
    DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices OemSvcEcIdle Status: %r\n", OemSvcStatus));
  }

Done:
  BiosCommDataBuffer->DataSize = ApCommDataBuffer->DataSize;
  BiosCommDataBuffer->PhysicalDataSize = ApCommDataBuffer->PhysicalDataSize;

  return Status;
}

/**
  AH=41h, OEM Extra Data Communication type 52h to populate header.

  @param[in]  ApCommDataBuffer   Pointer to AP communication data buffer.
  @param[out] BiosCommDataBuffer Pointer to BIOS communication data buffer.

  @retval EFI_SUCCESS   populate header successful.
**/
EFI_STATUS
Oa30PopulateHeaderFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{

  return EFI_SUCCESS;
}

/**
  AH=41h, OEM Extra Data Communication type 53h to de-populate header.

  @param[in]  ApCommDataBuffer   Pointer to AP communication data buffer.
  @param[out] BiosCommDataBuffer Pointer to BIOS communication data buffer.

  @retval EFI_SUCCESS   populate header successful.
**/
EFI_STATUS
Oa30DePopulateHeaderFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{

  return EFI_SUCCESS;
}

EFI_STATUS
BiosGuardUpdateHandleFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{
  if (IsBiosGuardSupport () == FALSE) {
    BiosCommDataBuffer->ErrorReturn = ERROR_RETURE_NOT_SUPPORT;
    return EFI_UNSUPPORTED;
  }

  BiosCommDataBuffer->BlockSize        = OemExtraMaximunBlockSize;
  BiosCommDataBuffer->DataSize         = OemExtraReportWriteSize;
  BiosCommDataBuffer->PhysicalDataSize = ApCommDataBuffer->PhysicalDataSize;

  return EFI_SUCCESS;
}

EFI_STATUS
BiosGuardReturnHandleFunction (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  OUT BIOS_COMMUNICATION_DATA_TABLE        *BiosCommDataBuffer
  )
{
  EFI_STATUS   Status;

  if (IsBiosGuardSupport () == FALSE) {
    BiosCommDataBuffer->ErrorReturn = ERROR_RETURE_NOT_SUPPORT;
    return EFI_UNSUPPORTED;
  }
  BiosCommDataBuffer->BlockSize        = OemExtraMaximunBlockSize;
  BiosCommDataBuffer->DataSize         = OemExtraReportWriteSize;
  BiosCommDataBuffer->PhysicalDataSize = ApCommDataBuffer->PhysicalDataSize;
  BiosCommDataBuffer->ErrorReturn      = ERROR_RETURE_RETURN_CODE_VALID;

  BiosCommDataBuffer->ReturnCode = AsmReadMsr64 (MSR_PLAT_FRMW_PROT_TRIG_PARAM) &
                                     (LShiftU64 (V_MSR_PLAT_FRMW_PROT_TRIG_PARAM_STATUS_MASK,
                                        N_MSR_PLAT_FRMW_PROT_TRIG_PARAM_STATUS_OFFSET) |
                                      LShiftU64 (V_MSR_PLAT_FRMW_PROT_TRIG_PARAM_DATA_MASK,
                                        N_MSR_PLAT_FRMW_PROT_TRIG_PARAM_DATA_OFFSET));
  if (mFlashME) {
    if (BiosCommDataBuffer->ReturnCode == 0x0) {
      Status = IhisiSuccess;
    } else {
      Status = FbtsWriteFail;
    }
    FlashMEAfterProcess(Status);
  }
  
  return EFI_SUCCESS;
}

EFI_STATUS
BiosGuardUpdateWrite (
  VOID
  )
{
  EFI_STATUS                            Status;
  UINT32                                BgupcSize;
  UINT32                                BgupcOffset;
  UINT32                                BufferSize;
  EFI_PHYSICAL_ADDRESS                  BgupCertificate;
  UINT8                                 *InputDataBuffer;
  UINT32                                DataSize;
  UINT32                                *BGSL;
  UINT32                                ROMOffset;
  Status          = EFI_SUCCESS;
  InputDataBuffer = NULL;
  BgupcOffset     = 0x00;
  BgupcSize       = 0x00;
  BufferSize      = 0x00;
  BgupCertificate = 0x00;
  DataSize        = 0x00;
  BGSL            = NULL;
  ROMOffset       = 0x00;
  
  if (IsBiosGuardSupport () == FALSE){
    return EFI_UNSUPPORTED;
  }
 
  InputDataBuffer = (UINT8*) (UINTN)  mH2OIhisi->ReadCpuReg32 (EFI_SMM_SAVE_STATE_REGISTER_RSI);
  BgupcOffset     = sizeof (BGUP_HEADER) + ((BGUP *) InputDataBuffer)->BgupHeader.ScriptSectionSize + ((BGUP *) InputDataBuffer)->BgupHeader.DataSectionSize;
  BufferSize      =  mH2OIhisi->ReadCpuReg32 (EFI_SMM_SAVE_STATE_REGISTER_RDI);
  BgupCertificate = (EFI_PHYSICAL_ADDRESS) (mBiosGuardMemAddress + mBiosGuardMemSize - BGUPC_MEMORY_OFFSET);

  if (!mH2OIhisi->BufferInCmdBuffer ((VOID *) InputDataBuffer, BufferSize)) {
    return EFI_INVALID_PARAMETER;
  }

  switch (((BGUPC_HEADER *)(InputDataBuffer + BgupcOffset))->Algorithm) {
  case 1:
    BgupcSize = sizeof (BGUPC_ALGORITHM_1);
    break;
  default:
    BgupcSize = sizeof (BGUPC_ALGORITHM_1);
    break;
  }

  if ((BgupcOffset + BgupcSize) != BufferSize) {
    return EFI_INVALID_PARAMETER;
  }

  ZeroMem ((VOID *)(UINT64) mBiosGuardMemAddress, mBiosGuardMemSize);
  CopyMem ((VOID *)(UINT64) mBiosGuardMemAddress, InputDataBuffer, BgupcOffset);
  CopyMem ((VOID *) BgupCertificate, InputDataBuffer + BgupcOffset, BgupcSize);

  if (!mFlashME){
    DataSize = ((BGUP_HEADER*)mBiosGuardMemAddress)->ScriptSectionSize;

    Status = gSmst->SmmAllocatePool (
                    EfiRuntimeServicesData,
                    DataSize,
                     (VOID **)&BGSL
                     );
    if (!EFI_ERROR (Status )) {
      CopyMem (BGSL, (VOID *)(mBiosGuardMemAddress + sizeof(BGUP_HEADER)), DataSize);
	  //
	  // 0x00000000 means Full image
	  // 0xFFFFFFFF means only BIOS
	  //
      if ((BGSL[BGSL_DST_TYPE_OFFSET]) == 0x00000000) {
        mWriteSize = BGSL[BGSL_SIZE_OFFSET];
        ROMOffset  = BGSL[BGSL_SPI_DST_ADDR_OFFSET];
        CheckInMERange (ROMOffset);
      }
        gSmst->SmmFreePool (BGSL);
    }
  }
  if (mFlashME){
    SetMeHalt ();
  }

  //
  // Use Intel BIOS Guard protocol to trigger BIOS Guard ACM
  //
//  Status = gSmst->SmmIo.Io.Write (&gSmst->SmmIo, SMM_IO_UINT8, mGlobalNvsArea->BiosGuardIoTrapAddress, 1, &Trigger);
  mBiosGuardProtocol->Execute (mBiosGuardProtocol, TRUE);

  return Status;
}

/**
  Function to write OA3.0 data and do action which request from IHISI function 42h.

  @retval EFI_SUCCESS   Successfully returns.
**/
EFI_STATUS
Oa30DataWrite (
  VOID
  )
{
  EFI_STATUS                       Status;
  EFI_STATUS                       OemSvcStatus;
  UINT32                           WriteSize;
  UINT8                            EraseCount;
  UINT8                            WriteCount;
  UINT8                            ShutdownMode;
  UINT32                           MsdmDataSize;
  UINTN                            RomBaseAddress;
  UINT8                           *WriteDataBuffer;
  UINT8                           *ReturnDataBuffer;
  UINTN                            Index2;
  UINTN                            EraseSize;
  UINT8                            *TEMP;

  WriteDataBuffer = (UINT8 *) (UINTN) mH2OIhisi->ReadCpuReg32(EFI_SMM_SAVE_STATE_REGISTER_RSI);
  WriteSize = (UINT32) mH2OIhisi->ReadCpuReg32 (EFI_SMM_SAVE_STATE_REGISTER_RDI);
  RomBaseAddress = (UINTN) FixedPcdGet32 (PcdFlashNvStorageMsdmDataBase);
  MsdmDataSize = sizeof (EFI_ACPI_MSDM_DATA_STRUCTURE);

  if (WriteSize == MsdmDataSize) {
    EraseSize = (UINTN) FixedPcdGet32 (PcdFlashNvStorageMsdmDataSize);
    ReturnDataBuffer = NULL;
    
    Status = gSmst->SmmAllocatePool (
                      EfiRuntimeServicesData,
                      EraseSize,
                      (VOID **)&ReturnDataBuffer
                      );
    if (EFI_ERROR (Status)) {
      return EFI_OUT_OF_RESOURCES;
    }

    *(mSmmFwBlockService->FlashMode) = SMM_FW_DEFAULT_MODE;
    Status = mSmmFwBlockService->Read (
                                   mSmmFwBlockService,
                                   RomBaseAddress,
                                   0,
                                   &EraseSize,
                                   ReturnDataBuffer
                                   );
    //
    // Only modify the first 0x31 bytes
    //
    TEMP   = ReturnDataBuffer;
    for (Index2 = 0; Index2 < MsdmDataSize; Index2++) {
      TEMP[Index2] = WriteDataBuffer[Index2];
    }

    Status = EFI_UNSUPPORTED;
    if (PcdGetBool (PcdEcSharedFlashSupported)) {
      DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices Call: OemSvcEcIdle \n"));
      OemSvcStatus = OemSvcEcIdle (TRUE);
      DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices OemSvcEcIdle Status: %r\n", OemSvcStatus));
    }
    
    if (IsBiosGuardSupport () && IsFlashWearOutSet()) {
        Status = mSmmVariable->SmmSetVariable (
                                 L"MsdmUpdate",
                                 &gMsdmAddressGuid,
                                 EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,
                                 MsdmDataSize,
                                 ReturnDataBuffer
                                 );
    } else {
      EraseCount      = 0;
      WriteCount      = 0;
      do {
        Status = mSmmFwBlockService->EraseBlocks (
                                       mSmmFwBlockService,
                                       RomBaseAddress,
                                       &EraseSize
                                       );
        if (!EFI_ERROR (Status)) {
          EraseCount = 0;
          Status = mSmmFwBlockService->Write (
                                         mSmmFwBlockService,
                                         RomBaseAddress,
                                         &EraseSize,
                                         ReturnDataBuffer
                                         );
          if (!EFI_ERROR (Status)) {
            goto WriteDone;
          } else {
            Status = IHISI_FBTS_WRITE_FAILED;
            WriteCount++;
          }
        } else {
          Status = IHISI_FBTS_ERASE_FAILED;
          EraseCount++;
        }
      } while ((EraseCount < 100) && (WriteCount < 100));
    }

    WriteDone:
      gSmst->SmmFreePool (ReturnDataBuffer);
      if (PcdGetBool (PcdEcSharedFlashSupported)) {
        DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices Call: OemSvcEcIdle \n"));
        OemSvcStatus = OemSvcEcIdle (FALSE);
        DEBUG_OEM_SVC ((DEBUG_INFO, "OemKernelServices OemSvcEcIdle Status: %r\n", OemSvcStatus));
      }
      
      if (EFI_ERROR(Status)){
        return EFI_ACCESS_DENIED;
      }
  } else {
    return EFI_INVALID_PARAMETER;
  }

  ShutdownMode = (UINT8) mH2OIhisi->ReadCpuReg32 (EFI_SMM_SAVE_STATE_REGISTER_RCX);
  switch (ShutdownMode) {

  case DoNothing:
    Status = EFI_SUCCESS;
    break;

  case WindowsReboot:
    Status = EFI_SUCCESS;
    break;

  case WindowsShutdown:
    Status = EFI_SUCCESS;
    break;

  case DosReboot:
    //
    // Note: Reboot by Oem hook
    //
    Status = IhisiFbtsReboot ();
    break;

  case DosShutdown:
    Status = IhisiFbtsShutDown ();
    break;

  default:
    Status = EFI_UNSUPPORTED;
    break;
  }

  return EFI_SUCCESS;
}

/**
  AH=41h(OemExtraDataCommunication),
  This function offers an interface to do IHISI Sub function AH=41h.

 @param[in]         ApCommDataBuffer    Pointer to AP communication data buffer.
 @param[in, out]    BiosCommDataBuffer  On entry, pointer to BIOS communication data buffer.
                                        On exit, points to updated BIOS communication data buffer.

 @retval            EFI_UNSUPPORTED     Returns unsupported by default.
 @retval            EFI_MEDIA_CHANGED   Alter the Configuration Parameter or hook code.
 @retval            EFI_SUCCESS         The function performs the same operation as caller.
                                        The caller will skip the specified behavior and assuming
                                        that it has been handled completely by this function.
*/
EFI_STATUS
EFIAPI
IhisiOemExtCommunication (
  IN  AP_COMMUNICATION_DATA_TABLE          *ApCommDataBuffer,
  IN OUT BIOS_COMMUNICATION_DATA_TABLE     *BiosCommDataBuffer
)
{
  EFI_STATUS                       Status;

  switch (ApCommDataBuffer->DataType) {
    case Oa30ReadWrite:
      Status = Oa30ReadWriteFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    case Oa30Erase:
      Status = Oa30EraseFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    case Oa30PopulateHeader:
      Status = Oa30PopulateHeaderFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    case Oa30DePopulateHeader:
      Status = Oa30DePopulateHeaderFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    case PfatUpdate:
      Status = BiosGuardUpdateHandleFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    case PfatReturn:
      Status = BiosGuardReturnHandleFunction (ApCommDataBuffer, BiosCommDataBuffer);
      break;

    default:
      Status = EFI_UNSUPPORTED;           //Return unsupported to indicate this is reserved function
      break;
  }

  if (EFI_ERROR (Status)) {
    return EFI_UNSUPPORTED;
  } else {
    CopyMem (ApCommDataBuffer, BiosCommDataBuffer, sizeof (BIOS_COMMUNICATION_DATA_TABLE));
    return EFI_SUCCESS;
  }

}

/**
  AH=42h(OemExtraDataWrite)
  This function offers an interface to do IHISI Sub function AH=42h,

 @param[in]         FunctionType      Function type.
 @param[in, out]    WriteDataBuffer   Pointer to input file data buffer.
 @param[in, out]    WriteSize         Write size.
 @param[in, out]    RomBaseAddress    Target offset to write.
 @param[in]         ShutdownMode      Shutdown mode.

 @retval            EFI_UNSUPPORTED     Returns unsupported by default.
 @retval            EFI_MEDIA_CHANGED   Alter the Configuration Parameter or hook code.
 @retval            EFI_SUCCESS         The function performs the same operation as caller.
                                        The caller will skip the specified behavior and assuming
                                        that it has been handled completely by this function.
*/
EFI_STATUS
EFIAPI
IhisiOemExtDataWrite (
  IN      UINT8                   FunctionType,
  IN OUT  UINT8                  *WriteDataBuffer,
  IN OUT  UINTN                  *WriteSize,
  IN OUT  UINTN                  *RomBaseAddress,
  IN      UINT8                   ShutdownMode
)
{
  EFI_STATUS                       Status;

  Status = EFI_UNSUPPORTED;

  switch (FunctionType) {
    case Oa30ReadWrite:
      Status = Oa30DataWrite ();
      break;

    case PfatUpdate:
      FunctionType = 0x00;
      Status = BiosGuardUpdateWrite ();
      break;

    default:
      Status = EFI_UNSUPPORTED;
      break;
    }

  return Status;
}

/**
 AH=47h(OemExtraDataRead),
 This function offers an interface to do IHISI Sub function AH=47h,

 @param[in]         FunctionType        Function type
 @param[in, out]    DataBuffer          Pointer to return data buffer.
 @param[in, out]    Size                Read size.
 @param[in, out]    RomBaseAddress      Read address.

 @retval            EFI_UNSUPPORTED     Returns unsupported by default.
 @retval            EFI_MEDIA_CHANGED   Alter the Configuration Parameter or hook code.
 @retval            EFI_SUCCESS         The function performs the same operation as caller.
                                        The caller will skip the specified behavior and assuming
                                        that it has been handled completely by this function.
*/
EFI_STATUS
EFIAPI
IhisiOemExtDataRead (
  IN UINT8                        FunctionType,
  IN OUT  UINT8                  *DataBuffer,
  IN OUT  UINTN                  *Size,
  IN OUT  UINTN                  *RomBaseAddress
)
{
  return EFI_UNSUPPORTED;
}