/**
  Destory FrameList buffer.

  @param  Uhc                    The UHCI device.

**/
VOID
UhciDestoryFrameList (
  IN USB_HC_DEV           *Uhc
  )
{
  //
  // Unmap the common buffer for framelist entry,
  // and free the common buffer.
  // Uhci's frame list occupy 4k memory.
  //
  Uhc->PciIo->Unmap (Uhc->PciIo, Uhc->FrameMapping);

  Uhc->PciIo->FreeBuffer (
                Uhc->PciIo,
                EFI_SIZE_TO_PAGES (4096),
                (VOID *) Uhc->FrameBase
                );

  if (Uhc->FrameBaseHostAddr != NULL) {
    FreePool (Uhc->FrameBaseHostAddr);
  }

  if (Uhc->SyncIntQh != NULL) {
    UsbHcFreeMem (Uhc->MemPool, Uhc->SyncIntQh, sizeof (UHCI_QH_SW));
  }

  if (Uhc->CtrlQh != NULL) {
    UsbHcFreeMem (Uhc->MemPool, Uhc->CtrlQh, sizeof (UHCI_QH_SW));
  }

  if (Uhc->BulkQh != NULL) {
    UsbHcFreeMem (Uhc->MemPool, Uhc->BulkQh, sizeof (UHCI_QH_SW));
  }

  Uhc->FrameBase           = NULL;
  Uhc->FrameBaseHostAddr   = NULL;
  Uhc->SyncIntQh           = NULL;
  Uhc->CtrlQh              = NULL;
  Uhc->BulkQh              = NULL;
}

/**
  Allocate reset vector buffer.

  @param[in, out]  CpuMpData  The pointer to CPU MP Data structure.
**/
VOID
AllocateResetVector (
  IN OUT CPU_MP_DATA          *CpuMpData
  )
{
  EFI_STATUS            Status;
  UINTN                 ApResetVectorSize;
  EFI_PHYSICAL_ADDRESS  StartAddress;

  if (CpuMpData->SaveRestoreFlag) {
    BackupAndPrepareWakeupBuffer (CpuMpData);
  } else {
    ApResetVectorSize = CpuMpData->AddressMap.RendezvousFunnelSize +
                        sizeof (MP_CPU_EXCHANGE_INFO);

    StartAddress = BASE_1MB;
    Status = gBS->AllocatePages (
                    AllocateMaxAddress,
                    EfiACPIMemoryNVS,
                    EFI_SIZE_TO_PAGES (ApResetVectorSize),
                    &StartAddress
                    );
    ASSERT_EFI_ERROR (Status);

    CpuMpData->WakeupBuffer      = (UINTN) StartAddress;
    CpuMpData->MpCpuExchangeInfo = (MP_CPU_EXCHANGE_INFO *) (UINTN)
                  (CpuMpData->WakeupBuffer + CpuMpData->AddressMap.RendezvousFunnelSize);
    //
    // copy AP reset code in it
    //
    CopyMem (
      (VOID *) CpuMpData->WakeupBuffer,
      (VOID *) CpuMpData->AddressMap.RendezvousFunnelAddress,
      CpuMpData->AddressMap.RendezvousFunnelSize
      );
  }
}

/**
  Initialize the shadow stack related data structure.

  @param CpuIndex     The index of CPU.
  @param ShadowStack  The bottom of the shadow stack for this CPU.
**/
VOID
InitShadowStack (
  IN UINTN  CpuIndex,
  IN VOID   *ShadowStack
  )
{
  UINTN       SmmShadowStackSize;
  UINT64      *InterruptSspTable;

  if ((PcdGet32 (PcdControlFlowEnforcementPropertyMask) != 0) && mCetSupported) {
    SmmShadowStackSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (PcdGet32 (PcdCpuSmmShadowStackSize)));
    if (FeaturePcdGet (PcdCpuSmmStackGuard)) {
      SmmShadowStackSize += EFI_PAGES_TO_SIZE (2);
    }
    mCetPl0Ssp = (UINT32)((UINTN)ShadowStack + SmmShadowStackSize - sizeof(UINT64));
    PatchInstructionX86 (mPatchCetPl0Ssp, mCetPl0Ssp, 4);
    DEBUG ((DEBUG_INFO, "mCetPl0Ssp - 0x%x\n", mCetPl0Ssp));
    DEBUG ((DEBUG_INFO, "ShadowStack - 0x%x\n", ShadowStack));
    DEBUG ((DEBUG_INFO, "  SmmShadowStackSize - 0x%x\n", SmmShadowStackSize));

    if (FeaturePcdGet (PcdCpuSmmStackGuard)) {
      if (mSmmInterruptSspTables == 0) {
        mSmmInterruptSspTables = (UINTN)AllocateZeroPool(sizeof(UINT64) * 8 * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus);
        ASSERT (mSmmInterruptSspTables != 0);
        DEBUG ((DEBUG_INFO, "mSmmInterruptSspTables - 0x%x\n", mSmmInterruptSspTables));
      }
      mCetInterruptSsp = (UINT32)((UINTN)ShadowStack + EFI_PAGES_TO_SIZE(1) - sizeof(UINT64));
      mCetInterruptSspTable = (UINT32)(UINTN)(mSmmInterruptSspTables + sizeof(UINT64) * 8 * CpuIndex);
      InterruptSspTable = (UINT64 *)(UINTN)mCetInterruptSspTable;
      InterruptSspTable[1] = mCetInterruptSsp;
      PatchInstructionX86 (mPatchCetInterruptSsp, mCetInterruptSsp, 4);
      PatchInstructionX86 (mPatchCetInterruptSspTable, mCetInterruptSspTable, 4);
      DEBUG ((DEBUG_INFO, "mCetInterruptSsp - 0x%x\n", mCetInterruptSsp));
      DEBUG ((DEBUG_INFO, "mCetInterruptSspTable - 0x%x\n", mCetInterruptSspTable));
    }
  }
}

/**
  Perform CPU specific actions required to migrate the PEI Services Table 
  pointer from temporary RAM to permanent RAM.

  For IA32 CPUs, the PEI Services Table pointer is stored in the 4 bytes 
  immediately preceding the Interrupt Descriptor Table (IDT) in memory.
  For X64 CPUs, the PEI Services Table pointer is stored in the 8 bytes 
  immediately preceding the Interrupt Descriptor Table (IDT) in memory.
  For Itanium and ARM CPUs, a the PEI Services Table Pointer is stored in
  a dedicated CPU register.  This means that there is no memory storage 
  associated with storing the PEI Services Table pointer, so no additional 
  migration actions are required for Itanium or ARM CPUs.

  If The cached PEI Services Table pointer is NULL, then ASSERT().
  If the permanent memory is allocated failed, then ASSERT().
**/
VOID
EFIAPI
MigratePeiServicesTablePointer (
  VOID
  )
{
  EFI_STATUS             Status;
  IA32_DESCRIPTOR        Idtr;
  EFI_PHYSICAL_ADDRESS   IdtBase;
  CONST EFI_PEI_SERVICES  **PeiServices;

  //
  // Get PEI Services Table pointer
  //
  AsmReadIdtr (&Idtr);
  PeiServices = (CONST EFI_PEI_SERVICES **) (*(UINTN*)(Idtr.Base - sizeof (UINTN)));
  ASSERT (PeiServices != NULL);
  //
  // Allocate the permanent memory.
  //
  Status = (*PeiServices)->AllocatePages (
                            PeiServices, 
                            EfiBootServicesCode,
                            EFI_SIZE_TO_PAGES(Idtr.Limit + 1 + sizeof (UINTN)),
                            &IdtBase
                            );
  ASSERT_EFI_ERROR (Status);
  //
  // Idt table needs to be migrated into memory.
  //
  CopyMem ((VOID *) (UINTN) IdtBase, (VOID *) (Idtr.Base - sizeof (UINTN)), Idtr.Limit + 1 + sizeof (UINTN));
  Idtr.Base = (UINTN) IdtBase + sizeof (UINTN);
  AsmWriteIdtr (&Idtr);
  
  return;
}

/**
  Initialize SMM profile data structures.

**/
VOID
InitSmmProfileInternal (
  VOID
  )
{
  EFI_STATUS                 Status;
  EFI_PHYSICAL_ADDRESS       Base;
  VOID                       *Registration;
  UINTN                      Index;
  UINTN                      MsrDsAreaSizePerCpu;
  UINTN                      TotalSize;

  mPFEntryCount = (UINTN *)AllocateZeroPool (sizeof (UINTN) * mMaxNumberOfCpus);
  ASSERT (mPFEntryCount != NULL);
  mLastPFEntryValue = (UINT64  (*)[MAX_PF_ENTRY_COUNT])AllocateZeroPool (
                                                         sizeof (mLastPFEntryValue[0]) * mMaxNumberOfCpus);
  ASSERT (mLastPFEntryValue != NULL);
  mLastPFEntryPointer = (UINT64 *(*)[MAX_PF_ENTRY_COUNT])AllocateZeroPool (
                                                           sizeof (mLastPFEntryPointer[0]) * mMaxNumberOfCpus);
  ASSERT (mLastPFEntryPointer != NULL);

  //
  // Allocate memory for SmmProfile below 4GB.
  // The base address
  //
  mSmmProfileSize = PcdGet32 (PcdCpuSmmProfileSize);
  ASSERT ((mSmmProfileSize & 0xFFF) == 0);

  if (mBtsSupported) {
    TotalSize = mSmmProfileSize + mMsrDsAreaSize;
  } else {
    TotalSize = mSmmProfileSize;
  }

  Base = 0xFFFFFFFF;
  Status = gBS->AllocatePages (
                  AllocateMaxAddress,
                  EfiReservedMemoryType,
                  EFI_SIZE_TO_PAGES (TotalSize),
                  &Base
                  );
  ASSERT_EFI_ERROR (Status);
  ZeroMem ((VOID *)(UINTN)Base, TotalSize);
  mSmmProfileBase = (SMM_PROFILE_HEADER *)(UINTN)Base;

  //
  // Initialize SMM profile data header.
  //
  mSmmProfileBase->HeaderSize     = sizeof (SMM_PROFILE_HEADER);
  mSmmProfileBase->MaxDataEntries = (UINT64)((mSmmProfileSize - sizeof(SMM_PROFILE_HEADER)) / sizeof (SMM_PROFILE_ENTRY));
  mSmmProfileBase->MaxDataSize    = MultU64x64 (mSmmProfileBase->MaxDataEntries, sizeof(SMM_PROFILE_ENTRY));
  mSmmProfileBase->CurDataEntries = 0;
  mSmmProfileBase->CurDataSize    = 0;
  mSmmProfileBase->TsegStart      = mCpuHotPlugData.SmrrBase;
  mSmmProfileBase->TsegSize       = mCpuHotPlugData.SmrrSize;
  mSmmProfileBase->NumSmis        = 0;
  mSmmProfileBase->NumCpus        = gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus;

  if (mBtsSupported) {
    mMsrDsArea = (MSR_DS_AREA_STRUCT **)AllocateZeroPool (sizeof (MSR_DS_AREA_STRUCT *) * mMaxNumberOfCpus);
    ASSERT (mMsrDsArea != NULL);
    mMsrBTSRecord = (BRANCH_TRACE_RECORD **)AllocateZeroPool (sizeof (BRANCH_TRACE_RECORD *) * mMaxNumberOfCpus);
    ASSERT (mMsrBTSRecord != NULL);
    mMsrPEBSRecord = (PEBS_RECORD **)AllocateZeroPool (sizeof (PEBS_RECORD *) * mMaxNumberOfCpus);
    ASSERT (mMsrPEBSRecord != NULL);

    mMsrDsAreaBase  = (MSR_DS_AREA_STRUCT *)((UINTN)Base + mSmmProfileSize);
    MsrDsAreaSizePerCpu = mMsrDsAreaSize / mMaxNumberOfCpus;
    mBTSRecordNumber    = (MsrDsAreaSizePerCpu - sizeof(PEBS_RECORD) * PEBS_RECORD_NUMBER - sizeof(MSR_DS_AREA_STRUCT)) / sizeof(BRANCH_TRACE_RECORD);
    for (Index = 0; Index < mMaxNumberOfCpus; Index++) {
      mMsrDsArea[Index]     = (MSR_DS_AREA_STRUCT *)((UINTN)mMsrDsAreaBase + MsrDsAreaSizePerCpu * Index);
      mMsrBTSRecord[Index]  = (BRANCH_TRACE_RECORD *)((UINTN)mMsrDsArea[Index] + sizeof(MSR_DS_AREA_STRUCT));
      mMsrPEBSRecord[Index] = (PEBS_RECORD *)((UINTN)mMsrDsArea[Index] + MsrDsAreaSizePerCpu - sizeof(PEBS_RECORD) * PEBS_RECORD_NUMBER);

      mMsrDsArea[Index]->BTSBufferBase          = (UINTN)mMsrBTSRecord[Index];
      mMsrDsArea[Index]->BTSIndex               = mMsrDsArea[Index]->BTSBufferBase;
      mMsrDsArea[Index]->BTSAbsoluteMaximum     = mMsrDsArea[Index]->BTSBufferBase + mBTSRecordNumber * sizeof(BRANCH_TRACE_RECORD) + 1;
      mMsrDsArea[Index]->BTSInterruptThreshold  = mMsrDsArea[Index]->BTSAbsoluteMaximum + 1;

      mMsrDsArea[Index]->PEBSBufferBase         = (UINTN)mMsrPEBSRecord[Index];
      mMsrDsArea[Index]->PEBSIndex              = mMsrDsArea[Index]->PEBSBufferBase;
      mMsrDsArea[Index]->PEBSAbsoluteMaximum    = mMsrDsArea[Index]->PEBSBufferBase + PEBS_RECORD_NUMBER * sizeof(PEBS_RECORD) + 1;
      mMsrDsArea[Index]->PEBSInterruptThreshold = mMsrDsArea[Index]->PEBSAbsoluteMaximum + 1;
    }
  }

  mProtectionMemRange      = mProtectionMemRangeTemplate;
  mProtectionMemRangeCount = sizeof (mProtectionMemRangeTemplate) / sizeof (MEMORY_PROTECTION_RANGE);

  //
  // Update TSeg entry.
  //
  mProtectionMemRange[0].Range.Base = mCpuHotPlugData.SmrrBase;
  mProtectionMemRange[0].Range.Top  = mCpuHotPlugData.SmrrBase + mCpuHotPlugData.SmrrSize;

  //
//.........这里部分代码省略.........

/**
  Main entry point.

  @param[in] ImageHandle    The firmware allocated handle for the EFI image.  
  @param[in] SystemTable    A pointer to the EFI System Table.
  
  @retval EFI_SUCCESS       Successfully initialized.

**/
EFI_STATUS
EFIAPI
FvbInitialize (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  )
{
  EFI_STATUS                          Status;
  VOID                                *Ptr;
  VOID                                *SubPtr;
  BOOLEAN                             Initialize;
  EFI_HANDLE                          Handle;
  EFI_PHYSICAL_ADDRESS                Address;
  RETURN_STATUS                       PcdStatus;

  DEBUG ((EFI_D_INFO, "EMU Variable FVB Started\n"));

  //
  // Verify that the PCD's are set correctly.
  //
  if (
       (PcdGet32 (PcdVariableStoreSize) +
        PcdGet32 (PcdFlashNvStorageFtwWorkingSize)
       ) >
       EMU_FVB_BLOCK_SIZE
     ) {
    DEBUG ((EFI_D_ERROR, "EMU Variable invalid PCD sizes\n"));
    return EFI_INVALID_PARAMETER;
  }

  if (PcdGet64 (PcdFlashNvStorageVariableBase64) != 0) {
    DEBUG ((EFI_D_INFO, "Disabling EMU Variable FVB since "
                        "flash variables appear to be supported.\n"));
    return EFI_ABORTED;
  }

  //
  // By default we will initialize the FV contents.  But, if
  // PcdEmuVariableNvStoreReserved is non-zero, then we will
  // use this location for our buffer.
  //
  // If this location does not have a proper FV header, then
  // we will initialize it.
  //
  Initialize = TRUE;
  if (PcdGet64 (PcdEmuVariableNvStoreReserved) != 0) {
    Ptr = (VOID*)(UINTN) PcdGet64 (PcdEmuVariableNvStoreReserved);
    DEBUG ((
      EFI_D_INFO,
      "EMU Variable FVB: Using pre-reserved block at %p\n",
      Ptr
      ));
    Status = ValidateFvHeader (Ptr);
    if (!EFI_ERROR (Status)) {
      DEBUG ((EFI_D_INFO, "EMU Variable FVB: Found valid pre-existing FV\n"));
      Initialize = FALSE;
    }
  } else {
    Ptr = AllocateAlignedRuntimePages (
            EFI_SIZE_TO_PAGES (EMU_FVB_SIZE),
            SIZE_64KB
            );
  }

  mEmuVarsFvb.BufferPtr = Ptr;

  //
  // Initialize the main FV header and variable store header
  //
  if (Initialize) {
    SetMem (Ptr, EMU_FVB_SIZE, ERASED_UINT8);
    InitializeFvAndVariableStoreHeaders (Ptr);
  }
  PcdStatus = PcdSet64S (PcdFlashNvStorageVariableBase64, (UINT32)(UINTN) Ptr);
  ASSERT_RETURN_ERROR (PcdStatus);

  //
  // Initialize the Fault Tolerant Write data area
  //
  SubPtr = (VOID*) ((UINT8*) Ptr + PcdGet32 (PcdVariableStoreSize));
  PcdStatus = PcdSet32S (PcdFlashNvStorageFtwWorkingBase,
                (UINT32)(UINTN) SubPtr);
  ASSERT_RETURN_ERROR (PcdStatus);

  //
  // Initialize the Fault Tolerant Write spare block
  //
  SubPtr = (VOID*) ((UINT8*) Ptr + EMU_FVB_BLOCK_SIZE);
  PcdStatus = PcdSet32S (PcdFlashNvStorageFtwSpareBase,
                (UINT32)(UINTN) SubPtr);
  ASSERT_RETURN_ERROR (PcdStatus);
//.........这里部分代码省略.........

/**
   Decompresses a section to the output buffer.

   This function looks up the compression type field in the input section and
   applies the appropriate compression algorithm to compress the section to a
   callee allocated buffer.
    
   @param  This                  Points to this instance of the
                                 EFI_PEI_DECOMPRESS_PEI PPI.
   @param  CompressionSection    Points to the compressed section.
   @param  OutputBuffer          Holds the returned pointer to the decompressed
                                 sections.
   @param  OutputSize            Holds the returned size of the decompress
                                 section streams.
   
   @retval EFI_SUCCESS           The section was decompressed successfully.
                                 OutputBuffer contains the resulting data and
                                 OutputSize contains the resulting size.

**/
EFI_STATUS
EFIAPI 
Decompress (
  IN CONST  EFI_PEI_DECOMPRESS_PPI  *This,
  IN CONST  EFI_COMPRESSION_SECTION *CompressionSection,
  OUT       VOID                    **OutputBuffer,
  OUT       UINTN                   *OutputSize
 )
{
  EFI_STATUS                      Status;
  UINT8                           *DstBuffer;
  UINT8                           *ScratchBuffer;
  UINT32                          DstBufferSize;
  UINT32                          ScratchBufferSize;
  VOID                            *CompressionSource;
  UINT32                          CompressionSourceSize;
  UINT32                          UncompressedLength;
  UINT8                           CompressionType;

  if (CompressionSection->CommonHeader.Type != EFI_SECTION_COMPRESSION) {
    ASSERT (FALSE);
    return EFI_INVALID_PARAMETER;
  }

  if (IS_SECTION2 (CompressionSection)) {
    CompressionSource = (VOID *) ((UINT8 *) CompressionSection + sizeof (EFI_COMPRESSION_SECTION2));
    CompressionSourceSize = (UINT32) (SECTION2_SIZE (CompressionSection) - sizeof (EFI_COMPRESSION_SECTION2));
    UncompressedLength = ((EFI_COMPRESSION_SECTION2 *) CompressionSection)->UncompressedLength;
    CompressionType = ((EFI_COMPRESSION_SECTION2 *) CompressionSection)->CompressionType;
  } else {
    CompressionSource = (VOID *) ((UINT8 *) CompressionSection + sizeof (EFI_COMPRESSION_SECTION));
    CompressionSourceSize = (UINT32) (SECTION_SIZE (CompressionSection) - sizeof (EFI_COMPRESSION_SECTION));
    UncompressedLength = CompressionSection->UncompressedLength;
    CompressionType = CompressionSection->CompressionType;
  }
  
  //
  // This is a compression set, expand it
  //
  switch (CompressionType) {
  case EFI_STANDARD_COMPRESSION:
    if (FeaturePcdGet(PcdDxeIplSupportUefiDecompress)) {
      //
      // Load EFI standard compression.
      // For compressed data, decompress them to destination buffer.
      //
      Status = UefiDecompressGetInfo (
                 CompressionSource,
                 CompressionSourceSize,
                 &DstBufferSize,
                 &ScratchBufferSize
                 );
      if (EFI_ERROR (Status)) {
        //
        // GetInfo failed
        //
        DEBUG ((DEBUG_ERROR, "Decompress GetInfo Failed - %r\n", Status));
        return EFI_NOT_FOUND;
      }
      //
      // Allocate scratch buffer
      //
      ScratchBuffer = AllocatePages (EFI_SIZE_TO_PAGES (ScratchBufferSize));
      if (ScratchBuffer == NULL) {
        return EFI_OUT_OF_RESOURCES;
      }
      //
      // Allocate destination buffer, extra one page for adjustment 
      //
      DstBuffer = AllocatePages (EFI_SIZE_TO_PAGES (DstBufferSize) + 1);
      if (DstBuffer == NULL) {
        return EFI_OUT_OF_RESOURCES;
      }
      //
      // DstBuffer still is one section. Adjust DstBuffer offset, skip EFI section header
      // to make section data at page alignment.
      //
      DstBuffer = DstBuffer + EFI_PAGE_SIZE - sizeof (EFI_COMMON_SECTION_HEADER);
      //
      // Call decompress function
//.........这里部分代码省略.........

/**
  The ExtractSection() function processes the input section and
  returns a pointer to the section contents. If the section being
  extracted does not require processing (if the section
  GuidedSectionHeader.Attributes has the
  EFI_GUIDED_SECTION_PROCESSING_REQUIRED field cleared), then
  OutputBuffer is just updated to point to the start of the
  section's contents. Otherwise, *Buffer must be allocated
  from PEI permanent memory.

  @param This                   Indicates the
                                EFI_PEI_GUIDED_SECTION_EXTRACTION_PPI instance.
                                Buffer containing the input GUIDed section to be
                                processed. OutputBuffer OutputBuffer is
                                allocated from PEI permanent memory and contains
                                the new section stream.
  @param InputSection           A pointer to the input buffer, which contains
                                the input section to be processed.
  @param OutputBuffer           A pointer to a caller-allocated buffer, whose
                                size is specified by the contents of OutputSize.
  @param OutputSize             A pointer to a caller-allocated
                                UINTN in which the size of *OutputBuffer
                                allocation is stored. If the function
                                returns anything other than EFI_SUCCESS,
                                the value of OutputSize is undefined.
  @param AuthenticationStatus   A pointer to a caller-allocated
                                UINT32 that indicates the
                                authentication status of the
                                output buffer. If the input
                                section's GuidedSectionHeader.
                                Attributes field has the
                                EFI_GUIDED_SECTION_AUTH_STATUS_VALID 
                                bit as clear,
                                AuthenticationStatus must return
                                zero. These bits reflect the
                                status of the extraction
                                operation. If the function
                                returns anything other than
                                EFI_SUCCESS, the value of
                                AuthenticationStatus is
                                undefined.
  
  @retval EFI_SUCCESS           The InputSection was
                                successfully processed and the
                                section contents were returned.
  
  @retval EFI_OUT_OF_RESOURCES  The system has insufficient
                                resources to process the request.
  
  @retval EFI_INVALID_PARAMETER The GUID in InputSection does
                                not match this instance of the
                                GUIDed Section Extraction PPI.

**/
EFI_STATUS
EFIAPI
CustomGuidedSectionExtract (
  IN CONST  EFI_PEI_GUIDED_SECTION_EXTRACTION_PPI *This,
  IN CONST  VOID                                  *InputSection,
  OUT       VOID                                  **OutputBuffer,
  OUT       UINTN                                 *OutputSize,
  OUT       UINT32                                *AuthenticationStatus
)
{
  EFI_STATUS      Status;
  UINT8           *ScratchBuffer;
  UINT32          ScratchBufferSize;
  UINT32          OutputBufferSize;
  UINT16          SectionAttribute;
  
  //
  // Init local variable
  //
  ScratchBuffer = NULL;

  //
  // Call GetInfo to get the size and attribute of input guided section data.
  //
  Status = ExtractGuidedSectionGetInfo (
             InputSection,
             &OutputBufferSize,
             &ScratchBufferSize,
             &SectionAttribute
             );
  
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_ERROR, "GetInfo from guided section Failed - %r\n", Status));
    return Status;
  }
  
  if (ScratchBufferSize != 0) {
    //
    // Allocate scratch buffer
    //
    ScratchBuffer = AllocatePages (EFI_SIZE_TO_PAGES (ScratchBufferSize));
    if (ScratchBuffer == NULL) {
      return EFI_OUT_OF_RESOURCES;
    }
  }

//.........这里部分代码省略.........

void
efi_main(EFI_HANDLE image_handle, EFI_SYSTEM_TABLE *system_table)
{
	static EFI_GUID image_protocol = LOADED_IMAGE_PROTOCOL;
	EFI_LOADED_IMAGE *img;
	CHAR16 *argp, *args, **argv;
	EFI_STATUS status;
	int argc, addprog;

	IH = image_handle;
	ST = system_table;
	BS = ST->BootServices;
	RS = ST->RuntimeServices;

	heapsize = 512*1024;
	status = BS->AllocatePages(AllocateAnyPages, EfiLoaderData,
	    EFI_SIZE_TO_PAGES(heapsize), &heap);
	if (status != EFI_SUCCESS)
		BS->Exit(IH, status, 0, NULL);

	setheap((void *)heap, (void *)(heap + heapsize));

	/* Use exit() from here on... */

	status = BS->HandleProtocol(IH, &image_protocol, (VOID**)&img);
	if (status != EFI_SUCCESS)
		exit(status);

	/*
	 * Pre-process the (optional) load options. If the option string
	 * is given as an ASCII string, we use a poor man's ASCII to
	 * Unicode-16 translation. The size of the option string as given
	 * to us includes the terminating null character. We assume the
	 * string is an ASCII string if strlen() plus the terminating
	 * '\0' is less than LoadOptionsSize. Even if all Unicode-16
	 * characters have the upper 8 bits non-zero, the terminating
	 * null character will cause a one-off.
	 * If the string is already in Unicode-16, we make a copy so that
	 * we know we can always modify the string.
	 */
	if (img->LoadOptionsSize > 0 && img->LoadOptions != NULL) {
		if (img->LoadOptionsSize == strlen(img->LoadOptions) + 1) {
			args = malloc(img->LoadOptionsSize << 1);
			for (argc = 0; argc < img->LoadOptionsSize; argc++)
				args[argc] = ((char*)img->LoadOptions)[argc];
		} else {
			args = malloc(img->LoadOptionsSize);
			memcpy(args, img->LoadOptions, img->LoadOptionsSize);
		}
	} else
		args = NULL;

	/*
	 * Use a quick and dirty algorithm to build the argv vector. We
	 * first count the number of words. Then, after allocating the
	 * vector, we split the string up. We don't deal with quotes or
	 * other more advanced shell features.
	 * The EFI shell will pas the name of the image as the first
	 * word in the argument list. This does not happen if we're
	 * loaded by the boot manager. This is not so easy to figure
	 * out though. The ParentHandle is not always NULL, because
	 * there can be a function (=image) that will perform the task
	 * for the boot manager.
	 */
	/* Part 1: Figure out if we need to add our program name. */
	addprog = (args == NULL || img->ParentHandle == NULL ||
	    img->FilePath == NULL) ? 1 : 0;
	if (!addprog) {
		addprog =
		    (DevicePathType(img->FilePath) != MEDIA_DEVICE_PATH ||
		     DevicePathSubType(img->FilePath) != MEDIA_FILEPATH_DP ||
		     DevicePathNodeLength(img->FilePath) <=
			sizeof(FILEPATH_DEVICE_PATH)) ? 1 : 0;
		if (!addprog) {
			/* XXX todo. */
		}
	}
	/* Part 2: count words. */
	argc = (addprog) ? 1 : 0;
	argp = args;
	while (argp != NULL && *argp != 0) {
		argp = arg_skipsep(argp);
		if (*argp == 0)
			break;
		argc++;
		argp = arg_skipword(argp);
	}
	/* Part 3: build vector. */
	argv = malloc((argc + 1) * sizeof(CHAR16*));
	argc = 0;
	if (addprog)
		argv[argc++] = L"loader.efi";
	argp = args;
	while (argp != NULL && *argp != 0) {
		argp = arg_skipsep(argp);
		if (*argp == 0)
			break;
		argv[argc++] = argp;
		argp = arg_skipword(argp);
		/* Terminate the words. */
//.........这里部分代码省略.........

int
ldr_bootinfo(struct bootinfo *bi, uint64_t *bi_addr)
{
	VOID *fpswa;
	EFI_MEMORY_DESCRIPTOR *mm;
	EFI_PHYSICAL_ADDRESS addr;
	EFI_HANDLE handle;
	EFI_STATUS status;
	size_t bisz;
	UINTN mmsz, pages, sz;
	UINT32 mmver;

	bi->bi_systab = (uint64_t)ST;
	bi->bi_hcdp = (uint64_t)efi_get_table(&hcdp_guid);

	sz = sizeof(EFI_HANDLE);
	status = BS->LocateHandle(ByProtocol, &fpswa_guid, 0, &sz, &handle);
	if (status == 0)
		status = BS->HandleProtocol(handle, &fpswa_guid, &fpswa);
	bi->bi_fpswa = (status == 0) ? (uint64_t)fpswa : 0;

	bisz = (sizeof(struct bootinfo) + 0x0f) & ~0x0f;

	/*
	 * Allocate enough pages to hold the bootinfo block and the memory
	 * map EFI will return to us. The memory map has an unknown size,
	 * so we have to determine that first. Note that the AllocatePages
	 * call can itself modify the memory map, so we have to take that
	 * into account as well. The changes to the memory map are caused
	 * by splitting a range of free memory into two (AFAICT), so that
	 * one is marked as being loader data.
	 */
	sz = 0;
	BS->GetMemoryMap(&sz, NULL, &mapkey, &mmsz, &mmver);
	sz += mmsz;
	sz = (sz + 15) & ~15;
	pages = EFI_SIZE_TO_PAGES(sz + bisz);
	status = BS->AllocatePages(AllocateAnyPages, EfiLoaderData, pages,
	    &addr);
	if (EFI_ERROR(status)) {
		printf("%s: AllocatePages() returned 0x%lx\n", __func__,
		    (long)status);
		return (ENOMEM);
	}

	/*
	 * Read the memory map and stash it after bootinfo. Align the
	 * memory map on a 16-byte boundary (the bootinfo block is page
	 * aligned).
	 */
	*bi_addr = addr;
	mm = (void *)(addr + bisz);
	sz = (EFI_PAGE_SIZE * pages) - bisz;
	status = BS->GetMemoryMap(&sz, mm, &mapkey, &mmsz, &mmver);
	if (EFI_ERROR(status)) {
		printf("%s: GetMemoryMap() returned 0x%lx\n", __func__,
		    (long)status);
		return (EINVAL);
	}
	bi->bi_memmap = (uint64_t)mm;
	bi->bi_memmap_size = sz;
	bi->bi_memdesc_size = mmsz;
	bi->bi_memdesc_version = mmver;

	bcopy(bi, (void *)(*bi_addr), sizeof(*bi));
	return (0);
}

VOID *
UncachedInternalAllocateAlignedPages (
  IN EFI_MEMORY_TYPE  MemoryType,  
  IN UINTN            Pages,
  IN UINTN            Alignment
  )
{
  EFI_STATUS                        Status;
  EFI_PHYSICAL_ADDRESS              Memory;
  EFI_PHYSICAL_ADDRESS              AlignedMemory;
  UINTN                             AlignmentMask;
  UINTN                             UnalignedPages;
  UINTN                             RealPages;
  EFI_GCD_MEMORY_SPACE_DESCRIPTOR   Descriptor;

  //
  // Alignment must be a power of two or zero.
  //
  ASSERT ((Alignment & (Alignment - 1)) == 0);
 
  if (Pages == 0) {
    return NULL;
  }
  if (Alignment > EFI_PAGE_SIZE) {
    //
    // Caculate the total number of pages since alignment is larger than page size.
    //
    AlignmentMask  = Alignment - 1;
    RealPages      = Pages + EFI_SIZE_TO_PAGES (Alignment);
    //
    // Make sure that Pages plus EFI_SIZE_TO_PAGES (Alignment) does not overflow.
    //
    ASSERT (RealPages > Pages);
 
    Status         = gBS->AllocatePages (AllocateAnyPages, MemoryType, RealPages, &Memory);
    if (EFI_ERROR (Status)) {
      return NULL;
    }
    AlignedMemory  = ((UINTN) Memory + AlignmentMask) & ~AlignmentMask;
    UnalignedPages = EFI_SIZE_TO_PAGES (AlignedMemory - (UINTN) Memory);
    if (UnalignedPages > 0) {
      //
      // Free first unaligned page(s).
      //
      Status = gBS->FreePages (Memory, UnalignedPages);
      ASSERT_EFI_ERROR (Status);
    }
    Memory         = (EFI_PHYSICAL_ADDRESS) (AlignedMemory + EFI_PAGES_TO_SIZE (Pages));
    UnalignedPages = RealPages - Pages - UnalignedPages;
    if (UnalignedPages > 0) {
      //
      // Free last unaligned page(s).
      //
      Status = gBS->FreePages (Memory, UnalignedPages);
      ASSERT_EFI_ERROR (Status);
    }
  } else {
    //
    // Do not over-allocate pages in this case.
    //
    Status = gBS->AllocatePages (AllocateAnyPages, MemoryType, Pages, &Memory);
    if (EFI_ERROR (Status)) {
      return NULL;
    }
    AlignedMemory  = (UINTN) Memory;
  }
  
  Status = gDS->GetMemorySpaceDescriptor (Memory, &Descriptor);
  if (!EFI_ERROR (Status)) {
    // We are making an assumption that all of memory has the same default attributes
    gAttributes = Descriptor.Attributes;
  }
  
  Status = gDS->SetMemorySpaceAttributes (Memory, EFI_PAGES_TO_SIZE (Pages), EFI_MEMORY_WC);
  ASSERT_EFI_ERROR (Status);
  
  return (VOID *)(UINTN)Memory;
}

/**
  Return the Virtual Memory Map of your platform

  This Virtual Memory Map is used by MemoryInitPei Module to initialize the MMU on your platform.

  @param[out]   VirtualMemoryMap    Array of ARM_MEMORY_REGION_DESCRIPTOR describing a Physical-to-
                                    Virtual Memory mapping. This array must be ended by a zero-filled
                                    entry

**/
VOID
ArmPlatformGetVirtualMemoryMap (
  IN ARM_MEMORY_REGION_DESCRIPTOR** VirtualMemoryMap
  )
{
  ARM_MEMORY_REGION_ATTRIBUTES  CacheAttributes;
  //EFI_RESOURCE_ATTRIBUTE_TYPE   ResourceAttributes;
  UINTN                         Index;
  ARM_MEMORY_REGION_DESCRIPTOR  *VirtualMemoryTable;
  //UINT32                        SysId;
  //BOOLEAN                       HasSparseMemory;
  //EFI_VIRTUAL_ADDRESS           SparseMemoryBase;
  //UINT64                        SparseMemorySize;
  EFI_PEI_HOB_POINTERS          NextHob;

  ASSERT (VirtualMemoryMap != NULL);

  VirtualMemoryTable = (ARM_MEMORY_REGION_DESCRIPTOR*)AllocatePages(EFI_SIZE_TO_PAGES (sizeof(ARM_MEMORY_REGION_DESCRIPTOR) * MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS));
  if (VirtualMemoryTable == NULL) {
      return;
  }

  if (FeaturePcdGet(PcdCacheEnable) == TRUE) {
      CacheAttributes = DDR_ATTRIBUTES_CACHED;
  } else {
      CacheAttributes = DDR_ATTRIBUTES_UNCACHED;
  }
/*
  // ReMap (Either NOR Flash or DRAM)
  VirtualMemoryTable[Index].PhysicalBase = ARM_VE_REMAP_BASE;
  VirtualMemoryTable[Index].VirtualBase  = ARM_VE_REMAP_BASE;
  VirtualMemoryTable[Index].Length       = ARM_VE_REMAP_SZ;

  if (FeaturePcdGet(PcdNorFlashRemapping) == FALSE) {
    // Map the NOR Flash as Secure Memory
    if (FeaturePcdGet(PcdCacheEnable) == TRUE) {
      VirtualMemoryTable[Index].Attributes   = DDR_ATTRIBUTES_CACHED;
    } else {
      VirtualMemoryTable[Index].Attributes   = DDR_ATTRIBUTES_UNCACHED;
    }
  } else {
    // DRAM mapping
    VirtualMemoryTable[Index].Attributes   = CacheAttributes;
  }
*/

  Index = OemSetVirtualMapDesc(VirtualMemoryTable, CacheAttributes);

  // Search for System Memory Hob that contains the EFI resource system memory  s00296804
  NextHob.Raw = GetHobList ();
  while ((NextHob.Raw = GetNextHob (EFI_HOB_TYPE_RESOURCE_DESCRIPTOR, NextHob.Raw)) != NULL)
  {
    if (NextHob.ResourceDescriptor->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY)
    {
        if (NextHob.ResourceDescriptor->PhysicalStart > BASE_4GB)//只修改4G以上的属性
        {
            VirtualMemoryTable[++Index].PhysicalBase = NextHob.ResourceDescriptor->PhysicalStart;
            VirtualMemoryTable[Index].VirtualBase  = NextHob.ResourceDescriptor->PhysicalStart;
            VirtualMemoryTable[Index].Length       =NextHob.ResourceDescriptor->ResourceLength;
            VirtualMemoryTable[Index].Attributes   =  CacheAttributes;
        }
    }

    NextHob.Raw = GET_NEXT_HOB (NextHob);
  }
  
  // End of Table
  VirtualMemoryTable[++Index].PhysicalBase = 0;
  VirtualMemoryTable[Index].VirtualBase  = 0;
  VirtualMemoryTable[Index].Length       = 0;
  VirtualMemoryTable[Index].Attributes   = (ARM_MEMORY_REGION_ATTRIBUTES)0;
  
  ASSERT((Index + 1) <= MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS);
  DEBUG((EFI_D_ERROR, "[%a]:[%dL] discriptor count=%d\n", __FUNCTION__, __LINE__, Index+1));

  *VirtualMemoryMap = VirtualMemoryTable;
}

/**
  Process a QEMU_LOADER_ALLOCATE command.

  @param[in] Allocate     The QEMU_LOADER_ALLOCATE command to process.

  @param[in,out] Tracker  The ORDERED_COLLECTION tracking the BLOB user
                          structures created thus far.

  @retval EFI_SUCCESS           An area of whole AcpiNVS pages has been
                                allocated for the blob contents, and the
                                contents have been saved. A BLOB object (user
                                structure) has been allocated from pool memory,
                                referencing the blob contents. The BLOB user
                                structure has been linked into Tracker.

  @retval EFI_PROTOCOL_ERROR    Malformed fw_cfg file name has been found in
                                Allocate, or the Allocate command references a
                                file that is already known by Tracker.

  @retval EFI_UNSUPPORTED       Unsupported alignment request has been found in
                                Allocate.

  @retval EFI_OUT_OF_RESOURCES  Pool allocation failed.

  @return                       Error codes from QemuFwCfgFindFile() and
                                gBS->AllocatePages().
**/
STATIC
EFI_STATUS
EFIAPI
ProcessCmdAllocate (
  IN CONST QEMU_LOADER_ALLOCATE *Allocate,
  IN OUT ORDERED_COLLECTION     *Tracker
  )
{
  FIRMWARE_CONFIG_ITEM FwCfgItem;
  UINTN                FwCfgSize;
  EFI_STATUS           Status;
  UINTN                NumPages;
  EFI_PHYSICAL_ADDRESS Address;
  BLOB                 *Blob;

  if (Allocate->File[QEMU_LOADER_FNAME_SIZE - 1] != '\0') {
    DEBUG ((EFI_D_ERROR, "%a: malformed file name\n", __FUNCTION__));
    return EFI_PROTOCOL_ERROR;
  }

  if (Allocate->Alignment > EFI_PAGE_SIZE) {
    DEBUG ((EFI_D_ERROR, "%a: unsupported alignment 0x%x\n", __FUNCTION__,
      Allocate->Alignment));
    return EFI_UNSUPPORTED;
  }

  Status = QemuFwCfgFindFile ((CHAR8 *)Allocate->File, &FwCfgItem, &FwCfgSize);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "%a: QemuFwCfgFindFile(\"%a\"): %r\n", __FUNCTION__,
      Allocate->File, Status));
    return Status;
  }

  NumPages = EFI_SIZE_TO_PAGES (FwCfgSize);
  Address = 0xFFFFFFFF;
  Status = gBS->AllocatePages (AllocateMaxAddress, EfiACPIMemoryNVS, NumPages,
                  &Address);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  Blob = AllocatePool (sizeof *Blob);
  if (Blob == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto FreePages;
  }
  CopyMem (Blob->File, Allocate->File, QEMU_LOADER_FNAME_SIZE);
  Blob->Size = FwCfgSize;
  Blob->Base = (VOID *)(UINTN)Address;
  Blob->HostsOnlyTableData = TRUE;

  Status = OrderedCollectionInsert (Tracker, NULL, Blob);
  if (Status == RETURN_ALREADY_STARTED) {
    DEBUG ((EFI_D_ERROR, "%a: duplicated file \"%a\"\n", __FUNCTION__,
      Allocate->File));
    Status = EFI_PROTOCOL_ERROR;
  }
  if (EFI_ERROR (Status)) {
    goto FreeBlob;
  }

  QemuFwCfgSelectItem (FwCfgItem);
  QemuFwCfgReadBytes (FwCfgSize, Blob->Base);
  ZeroMem (Blob->Base + Blob->Size, EFI_PAGES_TO_SIZE (NumPages) - Blob->Size);

  DEBUG ((EFI_D_VERBOSE, "%a: File=\"%a\" Alignment=0x%x Zone=%d Size=0x%Lx "
    "Address=0x%Lx\n", __FUNCTION__, Allocate->File, Allocate->Alignment,
    Allocate->Zone, (UINT64)Blob->Size, (UINT64)(UINTN)Blob->Base));
  return EFI_SUCCESS;

FreeBlob:
  FreePool (Blob);

//.........这里部分代码省略.........

//.........这里部分代码省略.........

  Tracker = OrderedCollectionInit (BlobCompare, BlobKeyCompare);
  if (Tracker == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto FreeLoader;
  }

  //
  // first pass: process the commands
  //
  for (LoaderEntry = LoaderStart; LoaderEntry < LoaderEnd; ++LoaderEntry) {
    switch (LoaderEntry->Type) {
    case QemuLoaderCmdAllocate:
      Status = ProcessCmdAllocate (&LoaderEntry->Command.Allocate, Tracker);
      break;

    case QemuLoaderCmdAddPointer:
      Status = ProcessCmdAddPointer (&LoaderEntry->Command.AddPointer,
                 Tracker);
      break;

    case QemuLoaderCmdAddChecksum:
      Status = ProcessCmdAddChecksum (&LoaderEntry->Command.AddChecksum,
                 Tracker);
      break;

    default:
      DEBUG ((EFI_D_VERBOSE, "%a: unknown loader command: 0x%x\n",
        __FUNCTION__, LoaderEntry->Type));
      break;
    }

    if (EFI_ERROR (Status)) {
      goto FreeTracker;
    }
  }

  InstalledKey = AllocatePool (INSTALLED_TABLES_MAX * sizeof *InstalledKey);
  if (InstalledKey == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto FreeTracker;
  }

  //
  // second pass: identify and install ACPI tables
  //
  Installed = 0;
  for (LoaderEntry = LoaderStart; LoaderEntry < LoaderEnd; ++LoaderEntry) {
    if (LoaderEntry->Type == QemuLoaderCmdAddPointer) {
      Status = Process2ndPassCmdAddPointer (&LoaderEntry->Command.AddPointer,
                 Tracker, AcpiProtocol, InstalledKey, &Installed);
      if (EFI_ERROR (Status)) {
        break;
      }
    }
  }

  if (EFI_ERROR (Status)) {
    //
    // roll back partial installation
    //
    while (Installed > 0) {
      --Installed;
      AcpiProtocol->UninstallAcpiTable (AcpiProtocol, InstalledKey[Installed]);
    }
  } else {
    DEBUG ((EFI_D_INFO, "%a: installed %d tables\n", __FUNCTION__, Installed));
  }

  FreePool (InstalledKey);

FreeTracker:
  //
  // Tear down the tracker infrastructure. Each fw_cfg blob will be left in
  // place only if we're exiting with success and the blob hosts data that is
  // not directly part of some ACPI table.
  //
  for (TrackerEntry = OrderedCollectionMin (Tracker); TrackerEntry != NULL;
       TrackerEntry = TrackerEntry2) {
    VOID *UserStruct;
    BLOB *Blob;

    TrackerEntry2 = OrderedCollectionNext (TrackerEntry);
    OrderedCollectionDelete (Tracker, TrackerEntry, &UserStruct);
    Blob = UserStruct;

    if (EFI_ERROR (Status) || Blob->HostsOnlyTableData) {
      DEBUG ((EFI_D_VERBOSE, "%a: freeing \"%a\"\n", __FUNCTION__,
        Blob->File));
      gBS->FreePages ((UINTN)Blob->Base, EFI_SIZE_TO_PAGES (Blob->Size));
    }
    FreePool (Blob);
  }
  OrderedCollectionUninit (Tracker);

FreeLoader:
  FreePool (LoaderStart);

  return Status;
}

STATIC
EFI_STATUS
EFIAPI
EmmcIdentificationMode (
  IN MMC_HOST_INSTANCE     *MmcHostInstance,
  IN OCR_RESPONSE           Response
  )
{
  EFI_MMC_HOST_PROTOCOL *Host;
  EFI_BLOCK_IO_MEDIA    *Media;
  EFI_STATUS Status;
  EMMC_DEVICE_STATE     State;
  UINT32     RCA;

  Host  = MmcHostInstance->MmcHost;
  Media = MmcHostInstance->BlockIo.Media;

  // Fetch card identity register
  Status = Host->SendCommand (Host, MMC_CMD2, 0);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): Failed to send CMD2, Status=%r.\n", Status));
    return Status;
  }

  Status = Host->ReceiveResponse (Host, MMC_RESPONSE_TYPE_R2, (UINT32 *)&(MmcHostInstance->CardInfo.CIDData));
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): CID retrieval error, Status=%r.\n", Status));
    return Status;
  }

  // Assign a relative address value to the card
  MmcHostInstance->CardInfo.RCA = ++mEmmcRcaCount; // TODO: might need a more sophisticated way of doing this
  RCA = MmcHostInstance->CardInfo.RCA << RCA_SHIFT_OFFSET;
  Status = Host->SendCommand (Host, MMC_CMD3, RCA);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): RCA set error, Status=%r.\n", Status));
    return Status;
  }

  // Fetch card specific data
  Status = Host->SendCommand (Host, MMC_CMD9, RCA);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): Failed to send CMD9, Status=%r.\n", Status));
    return Status;
  }

  Status = Host->ReceiveResponse (Host, MMC_RESPONSE_TYPE_R2, (UINT32 *)&(MmcHostInstance->CardInfo.CSDData));
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): CSD retrieval error, Status=%r.\n", Status));
    return Status;
  }

  // Select the card
  Status = Host->SendCommand (Host, MMC_CMD7, RCA);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): Card selection error, Status=%r.\n", Status));
  }

  if (MMC_HOST_HAS_SETIOS(Host)) {
    // Set 1-bit bus width
    Status = Host->SetIos (Host, 0, 1, EMMCBACKWARD);
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): Set 1-bit bus width error, Status=%r.\n", Status));
      return Status;
    }

    // Set 1-bit bus width for EXTCSD
    Status = EmmcSetEXTCSD (MmcHostInstance, EXTCSD_BUS_WIDTH, EMMC_BUS_WIDTH_1BIT);
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): Set extcsd bus width error, Status=%r.\n", Status));
      return Status;
    }
  }

  // Fetch ECSD
  MmcHostInstance->CardInfo.ECSDData = AllocatePages (EFI_SIZE_TO_PAGES (sizeof (ECSD)));
  if (MmcHostInstance->CardInfo.ECSDData == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }
  Status = Host->SendCommand (Host, MMC_CMD8, 0);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): ECSD fetch error, Status=%r.\n", Status));
  }

  Status = Host->ReadBlockData (Host, 0, 512, (UINT32 *)MmcHostInstance->CardInfo.ECSDData);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "EmmcIdentificationMode(): ECSD read error, Status=%r.\n&