/** @file
  EFI PEI Core dispatch services

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
(C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "PeiMain.h"

/**

  Discover all Peims and optional Apriori file in one FV. There is at most one
  Apriori file in one FV.


  @param Private          Pointer to the private data passed in from caller
  @param CoreFileHandle   The instance of PEI_CORE_FV_HANDLE.

**/
VOID
DiscoverPeimsAndOrderWithApriori (
  IN  PEI_CORE_INSTANCE    *Private,
  IN  PEI_CORE_FV_HANDLE   *CoreFileHandle
  )
{
  EFI_STATUS                          Status;
  EFI_PEI_FILE_HANDLE                 FileHandle;
  EFI_PEI_FILE_HANDLE                 AprioriFileHandle;
  EFI_GUID                            *Apriori;
  UINTN                               Index;
  UINTN                               Index2;
  UINTN                               PeimIndex;
  UINTN                               PeimCount;
  EFI_GUID                            *Guid;
  EFI_PEI_FILE_HANDLE                 *TempFileHandles;
  EFI_GUID                            *TempFileGuid;
  EFI_PEI_FIRMWARE_VOLUME_PPI         *FvPpi;
  EFI_FV_FILE_INFO                    FileInfo;

  FvPpi = CoreFileHandle->FvPpi;

  //
  // Walk the FV and find all the PEIMs and the Apriori file.
  //
  AprioriFileHandle = NULL;
  Private->CurrentFvFileHandles = NULL;
  Guid = NULL;

  //
  // If the current Fv has been scanned, directly get its cached records.
  //
  if (CoreFileHandle->ScanFv) {
    Private->CurrentFvFileHandles = CoreFileHandle->FvFileHandles;
    return;
  }

  TempFileHandles = Private->TempFileHandles;
  TempFileGuid    = Private->TempFileGuid;

  //
  // Go ahead to scan this Fv, get PeimCount and cache FileHandles within it to TempFileHandles.
  //
  PeimCount = 0;
  FileHandle = NULL;
  do {
    Status = FvPpi->FindFileByType (FvPpi, PEI_CORE_INTERNAL_FFS_FILE_DISPATCH_TYPE, CoreFileHandle->FvHandle, &FileHandle);
    if (!EFI_ERROR (Status)) {
      if (PeimCount >= Private->TempPeimCount) {
        //
        // Run out of room, grow the buffer.
        //
        TempFileHandles = AllocatePool (
                            sizeof (EFI_PEI_FILE_HANDLE) * (Private->TempPeimCount + TEMP_FILE_GROWTH_STEP));
        ASSERT (TempFileHandles != NULL);
        CopyMem (
          TempFileHandles,
          Private->TempFileHandles,
          sizeof (EFI_PEI_FILE_HANDLE) * Private->TempPeimCount
          );
        Private->TempFileHandles = TempFileHandles;
        TempFileGuid = AllocatePool (
                         sizeof (EFI_GUID) * (Private->TempPeimCount + TEMP_FILE_GROWTH_STEP));
        ASSERT (TempFileGuid != NULL);
        CopyMem (
          TempFileGuid,
          Private->TempFileGuid,
          sizeof (EFI_GUID) * Private->TempPeimCount
          );
        Private->TempFileGuid = TempFileGuid;
        Private->TempPeimCount = Private->TempPeimCount + TEMP_FILE_GROWTH_STEP;
      }

      TempFileHandles[PeimCount++] = FileHandle;
    }
  } while (!EFI_ERROR (Status));

  DEBUG ((
    DEBUG_INFO,
    "%a(): Found 0x%x PEI FFS files in the %dth FV\n",
    __FUNCTION__,
    PeimCount,
    Private->CurrentPeimFvCount
    ));

  if (PeimCount == 0) {
    //
    // No PEIM FFS file is found, set ScanFv flag and return.
    //
    CoreFileHandle->ScanFv = TRUE;
    return;
  }

  //
  // Record PeimCount, allocate buffer for PeimState and FvFileHandles.
  //
  CoreFileHandle->PeimCount = PeimCount;
  CoreFileHandle->PeimState = AllocateZeroPool (sizeof (UINT8) * PeimCount);
  ASSERT (CoreFileHandle->PeimState != NULL);
  CoreFileHandle->FvFileHandles = AllocateZeroPool (sizeof (EFI_PEI_FILE_HANDLE) * PeimCount);
  ASSERT (CoreFileHandle->FvFileHandles != NULL);

  //
  // Get Apriori File handle
  //
  Private->AprioriCount = 0;
  Status = FvPpi->FindFileByName (FvPpi, &gPeiAprioriFileNameGuid, &CoreFileHandle->FvHandle, &AprioriFileHandle);
  if (!EFI_ERROR(Status) && AprioriFileHandle != NULL) {
    //
    // Read the Apriori file
    //
    Status = FvPpi->FindSectionByType (FvPpi, EFI_SECTION_RAW, AprioriFileHandle, (VOID **) &Apriori);
    if (!EFI_ERROR (Status)) {
      //
      // Calculate the number of PEIMs in the Apriori file
      //
      Status = FvPpi->GetFileInfo (FvPpi, AprioriFileHandle, &FileInfo);
      ASSERT_EFI_ERROR (Status);
      Private->AprioriCount = FileInfo.BufferSize;
      if (IS_SECTION2 (FileInfo.Buffer)) {
        Private->AprioriCount -= sizeof (EFI_COMMON_SECTION_HEADER2);
      } else {
        Private->AprioriCount -= sizeof (EFI_COMMON_SECTION_HEADER);
      }
      Private->AprioriCount /= sizeof (EFI_GUID);

      for (Index = 0; Index < PeimCount; Index++) {
        //
        // Make an array of file name guids that matches the FileHandle array so we can convert
        // quickly from file name to file handle
        //
        Status = FvPpi->GetFileInfo (FvPpi, TempFileHandles[Index], &FileInfo);
        ASSERT_EFI_ERROR (Status);
        CopyMem (&TempFileGuid[Index], &FileInfo.FileName, sizeof(EFI_GUID));
      }

      //
      // Walk through TempFileGuid array to find out who is invalid PEIM guid in Apriori file.
      // Add available PEIMs in Apriori file into FvFileHandles array.
      //
      Index = 0;
      for (Index2 = 0; Index2 < Private->AprioriCount; Index2++) {
        Guid = ScanGuid (TempFileGuid, PeimCount * sizeof (EFI_GUID), &Apriori[Index2]);
        if (Guid != NULL) {
          PeimIndex = ((UINTN)Guid - (UINTN)&TempFileGuid[0])/sizeof (EFI_GUID);
          CoreFileHandle->FvFileHandles[Index++] = TempFileHandles[PeimIndex];

          //
          // Since we have copied the file handle we can remove it from this list.
          //
          TempFileHandles[PeimIndex] = NULL;
        }
      }

      //
      // Update valid AprioriCount
      //
      Private->AprioriCount = Index;

      //
      // Add in any PEIMs not in the Apriori file
      //
      for (Index2 = 0; Index2 < PeimCount; Index2++) {
        if (TempFileHandles[Index2] != NULL) {
          CoreFileHandle->FvFileHandles[Index++] = TempFileHandles[Index2];
          TempFileHandles[Index2] = NULL;
        }
      }
      ASSERT (Index == PeimCount);
    }
  } else {
    CopyMem (CoreFileHandle->FvFileHandles, TempFileHandles, sizeof (EFI_PEI_FILE_HANDLE) * PeimCount);
  }

  //
  // The current Fv File Handles have been cached. So that we don't have to scan the Fv again.
  // Instead, we can retrieve the file handles within this Fv from cached records.
  //
  CoreFileHandle->ScanFv = TRUE;
  Private->CurrentFvFileHandles = CoreFileHandle->FvFileHandles;
}

//
// This is the minimum memory required by DxeCore initialization. When LMFA feature enabled,
// This part of memory still need reserved on the very top of memory so that the DXE Core could
// use these memory for data initialization. This macro should be sync with the same marco
// defined in DXE Core.
//
#define MINIMUM_INITIAL_MEMORY_SIZE 0x10000
/**
  This function is to test if the memory range described in resource HOB is available or not.

  This function should only be invoked when Loading Module at Fixed Address(LMFA) feature is enabled. Some platform may allocate the
  memory before PeiLoadFixAddressHook in invoked. so this function is to test if the memory range described by the input resource HOB is
  available or not.

  @param PrivateData         Pointer to the private data passed in from caller
  @param ResourceHob         Pointer to a resource HOB which described the memory range described by the input resource HOB
**/
BOOLEAN
PeiLoadFixAddressIsMemoryRangeAvailable (
  IN PEI_CORE_INSTANCE                  *PrivateData,
  IN EFI_HOB_RESOURCE_DESCRIPTOR        *ResourceHob
  )
{
  EFI_HOB_MEMORY_ALLOCATION          *MemoryHob;
  BOOLEAN                             IsAvailable;
  EFI_PEI_HOB_POINTERS                Hob;

  IsAvailable = TRUE;
  if (PrivateData == NULL || ResourceHob == NULL) {
    return FALSE;
  }
  //
  // test if the memory range describe in the HOB is already allocated.
  //
  for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
    //
    // See if this is a memory allocation HOB
    //
    if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_MEMORY_ALLOCATION) {
      MemoryHob = Hob.MemoryAllocation;
      if(MemoryHob->AllocDescriptor.MemoryBaseAddress == ResourceHob->PhysicalStart &&
         MemoryHob->AllocDescriptor.MemoryBaseAddress + MemoryHob->AllocDescriptor.MemoryLength == ResourceHob->PhysicalStart + ResourceHob->ResourceLength) {
         IsAvailable = FALSE;
         break;
       }
     }
  }

  return IsAvailable;

}
/**
  Hook function for Loading Module at Fixed Address feature

  This function should only be invoked when Loading Module at Fixed Address(LMFA) feature is enabled. When feature is
  configured as Load Modules at Fix Absolute Address, this function is to validate the top address assigned by user. When
  feature is configured as Load Modules at Fixed Offset, the functino is to find the top address which is TOLM-TSEG in general.
  And also the function will re-install PEI memory.

  @param PrivateData         Pointer to the private data passed in from caller

**/
VOID
PeiLoadFixAddressHook(
  IN PEI_CORE_INSTANCE           *PrivateData
  )
{
  EFI_PHYSICAL_ADDRESS               TopLoadingAddress;
  UINT64                             PeiMemorySize;
  UINT64                             TotalReservedMemorySize;
  UINT64                             MemoryRangeEnd;
  EFI_PHYSICAL_ADDRESS               HighAddress;
  EFI_HOB_RESOURCE_DESCRIPTOR        *ResourceHob;
  EFI_HOB_RESOURCE_DESCRIPTOR        *NextResourceHob;
  EFI_HOB_RESOURCE_DESCRIPTOR        *CurrentResourceHob;
  EFI_PEI_HOB_POINTERS               CurrentHob;
  EFI_PEI_HOB_POINTERS               Hob;
  EFI_PEI_HOB_POINTERS               NextHob;
  EFI_HOB_MEMORY_ALLOCATION          *MemoryHob;
  //
  // Initialize Local Variables
  //
  CurrentResourceHob    = NULL;
  ResourceHob           = NULL;
  NextResourceHob       = NULL;
  HighAddress           = 0;
  TopLoadingAddress     = 0;
  MemoryRangeEnd      = 0;
  CurrentHob.Raw      = PrivateData->HobList.Raw;
  PeiMemorySize = PrivateData->PhysicalMemoryLength;
  //
  // The top reserved memory include 3 parts: the topest range is for DXE core initialization with the size  MINIMUM_INITIAL_MEMORY_SIZE
  // then RuntimeCodePage range and Boot time code range.
  //
  TotalReservedMemorySize = MINIMUM_INITIAL_MEMORY_SIZE + EFI_PAGES_TO_SIZE(PcdGet32(PcdLoadFixAddressRuntimeCodePageNumber));
  TotalReservedMemorySize+= EFI_PAGES_TO_SIZE(PcdGet32(PcdLoadFixAddressBootTimeCodePageNumber)) ;
  //
  // PEI memory range lies below the top reserved memory
  //
  TotalReservedMemorySize += PeiMemorySize;

  DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: PcdLoadFixAddressRuntimeCodePageNumber= 0x%x.\n", PcdGet32(PcdLoadFixAddressRuntimeCodePageNumber)));
  DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: PcdLoadFixAddressBootTimeCodePageNumber= 0x%x.\n", PcdGet32(PcdLoadFixAddressBootTimeCodePageNumber)));
  DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: PcdLoadFixAddressPeiCodePageNumber= 0x%x.\n", PcdGet32(PcdLoadFixAddressPeiCodePageNumber)));
  DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: Total Reserved Memory Size = 0x%lx.\n", TotalReservedMemorySize));
  //
  // Loop through the system memory typed hob to merge the adjacent memory range
  //
  for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
    //
    // See if this is a resource descriptor HOB
    //
    if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {

      ResourceHob = Hob.ResourceDescriptor;
      //
      // If range described in this hob is not system memory or heigher than MAX_ADDRESS, ignored.
      //
      if (ResourceHob->ResourceType != EFI_RESOURCE_SYSTEM_MEMORY ||
          ResourceHob->PhysicalStart + ResourceHob->ResourceLength > MAX_ADDRESS)   {
        continue;
      }

      for (NextHob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(NextHob); NextHob.Raw = GET_NEXT_HOB(NextHob)) {
        if (NextHob.Raw == Hob.Raw){
          continue;
        }
        //
        // See if this is a resource descriptor HOB
        //
        if (GET_HOB_TYPE (NextHob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {

          NextResourceHob = NextHob.ResourceDescriptor;
          //
          // test if range described in this NextResourceHob is system memory and have the same attribute.
          // Note: Here is a assumption that system memory should always be healthy even without test.
          //
          if (NextResourceHob->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY &&
             (((NextResourceHob->ResourceAttribute^ResourceHob->ResourceAttribute)&(~EFI_RESOURCE_ATTRIBUTE_TESTED)) == 0)){

              //
              // See if the memory range described in ResourceHob and NextResourceHob is adjacent
              //
              if ((ResourceHob->PhysicalStart <= NextResourceHob->PhysicalStart &&
                    ResourceHob->PhysicalStart + ResourceHob->ResourceLength >= NextResourceHob->PhysicalStart)||
                  (ResourceHob->PhysicalStart >= NextResourceHob->PhysicalStart&&
                     ResourceHob->PhysicalStart <= NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength)) {

                MemoryRangeEnd = ((ResourceHob->PhysicalStart + ResourceHob->ResourceLength)>(NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength)) ?
                                     (ResourceHob->PhysicalStart + ResourceHob->ResourceLength):(NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength);

                ResourceHob->PhysicalStart = (ResourceHob->PhysicalStart < NextResourceHob->PhysicalStart) ?
                                                    ResourceHob->PhysicalStart : NextResourceHob->PhysicalStart;


                ResourceHob->ResourceLength = (MemoryRangeEnd - ResourceHob->PhysicalStart);

                ResourceHob->ResourceAttribute = ResourceHob->ResourceAttribute & (~EFI_RESOURCE_ATTRIBUTE_TESTED);
                //
                // Delete the NextResourceHob by marking it as unused.
                //
                GET_HOB_TYPE (NextHob) = EFI_HOB_TYPE_UNUSED;

              }
           }
        }
      }
    }
  }
  //
  // Some platform is already allocated pages before the HOB re-org. Here to build dedicated resource HOB to describe
  //  the allocated memory range
  //
  for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
    //
    // See if this is a memory allocation HOB
    //
    if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_MEMORY_ALLOCATION) {
      MemoryHob = Hob.MemoryAllocation;
      for (NextHob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(NextHob); NextHob.Raw = GET_NEXT_HOB(NextHob)) {
        //
        // See if this is a resource descriptor HOB
        //
        if (GET_HOB_TYPE (NextHob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {
          NextResourceHob = NextHob.ResourceDescriptor;
          //
          // If range described in this hob is not system memory or heigher than MAX_ADDRESS, ignored.
          //
          if (NextResourceHob->ResourceType != EFI_RESOURCE_SYSTEM_MEMORY || NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength > MAX_ADDRESS) {
            continue;
          }
          //
          // If the range describe in memory allocation HOB  belongs to the memroy range described by the resource hob
          //
          if (MemoryHob->AllocDescriptor.MemoryBaseAddress >= NextResourceHob->PhysicalStart &&
              MemoryHob->AllocDescriptor.MemoryBaseAddress + MemoryHob->AllocDescriptor.MemoryLength <= NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength) {
             //
             // Build seperate resource hob for this allocated range
             //
             if (MemoryHob->AllocDescriptor.MemoryBaseAddress > NextResourceHob->PhysicalStart) {
               BuildResourceDescriptorHob (
                 EFI_RESOURCE_SYSTEM_MEMORY,
                 NextResourceHob->ResourceAttribute,
                 NextResourceHob->PhysicalStart,
                 (MemoryHob->AllocDescriptor.MemoryBaseAddress - NextResourceHob->PhysicalStart)
               );
             }
             if (MemoryHob->AllocDescriptor.MemoryBaseAddress + MemoryHob->AllocDescriptor.MemoryLength < NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength) {
               BuildResourceDescriptorHob (
                 EFI_RESOURCE_SYSTEM_MEMORY,
                 NextResourceHob->ResourceAttribute,
                 MemoryHob->AllocDescriptor.MemoryBaseAddress + MemoryHob->AllocDescriptor.MemoryLength,
                 (NextResourceHob->PhysicalStart + NextResourceHob->ResourceLength -(MemoryHob->AllocDescriptor.MemoryBaseAddress + MemoryHob->AllocDescriptor.MemoryLength))
               );
             }
             NextResourceHob->PhysicalStart = MemoryHob->AllocDescriptor.MemoryBaseAddress;
             NextResourceHob->ResourceLength = MemoryHob->AllocDescriptor.MemoryLength;
             break;
          }
        }
      }
    }
  }

  //
  // Try to find and validate the TOP address.
  //
  if ((INT64)PcdGet64(PcdLoadModuleAtFixAddressEnable) > 0 ) {
    //
    // The LMFA feature is enabled as load module at fixed absolute address.
    //
    TopLoadingAddress = (EFI_PHYSICAL_ADDRESS)PcdGet64(PcdLoadModuleAtFixAddressEnable);
    DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: Loading module at fixed absolute address.\n"));
    //
    // validate the Address. Loop the resource descriptor HOB to make sure the address is in valid memory range
    //
    if ((TopLoadingAddress & EFI_PAGE_MASK) != 0) {
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED ERROR:Top Address 0x%lx is invalid since top address should be page align. \n", TopLoadingAddress));
      ASSERT (FALSE);
    }
    //
    // Search for a memory region that is below MAX_ADDRESS and in which TopLoadingAddress lies
    //
    for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
      //
      // See if this is a resource descriptor HOB
      //
      if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {

        ResourceHob = Hob.ResourceDescriptor;
        //
        // See if this resource descrior HOB describes tested system memory below MAX_ADDRESS
        //
        if (ResourceHob->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY &&
            ResourceHob->PhysicalStart + ResourceHob->ResourceLength <= MAX_ADDRESS) {
            //
            // See if Top address specified by user is valid.
            //
            if (ResourceHob->PhysicalStart + TotalReservedMemorySize < TopLoadingAddress &&
                (ResourceHob->PhysicalStart + ResourceHob->ResourceLength - MINIMUM_INITIAL_MEMORY_SIZE) >= TopLoadingAddress &&
                PeiLoadFixAddressIsMemoryRangeAvailable(PrivateData, ResourceHob)) {
              CurrentResourceHob = ResourceHob;
              CurrentHob = Hob;
              break;
           }
        }
      }
    }
    if (CurrentResourceHob != NULL) {
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO:Top Address 0x%lx is valid \n",  TopLoadingAddress));
      TopLoadingAddress += MINIMUM_INITIAL_MEMORY_SIZE;
    } else {
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED ERROR:Top Address 0x%lx is invalid \n",  TopLoadingAddress));
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED ERROR:The recommended Top Address for the platform is: \n"));
      //
      // Print the recomended Top address range.
      //
      for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
        //
        // See if this is a resource descriptor HOB
        //
        if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {

          ResourceHob = Hob.ResourceDescriptor;
          //
          // See if this resource descrior HOB describes tested system memory below MAX_ADDRESS
          //
          if (ResourceHob->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY &&
              ResourceHob->PhysicalStart + ResourceHob->ResourceLength <= MAX_ADDRESS) {
              //
              // See if Top address specified by user is valid.
              //
              if (ResourceHob->ResourceLength > TotalReservedMemorySize && PeiLoadFixAddressIsMemoryRangeAvailable(PrivateData, ResourceHob)) {
                 DEBUG ((EFI_D_INFO, "(0x%lx, 0x%lx)\n",
                          (ResourceHob->PhysicalStart + TotalReservedMemorySize -MINIMUM_INITIAL_MEMORY_SIZE),
                          (ResourceHob->PhysicalStart + ResourceHob->ResourceLength -MINIMUM_INITIAL_MEMORY_SIZE)
                        ));
              }
          }
        }
      }
      //
      // Assert here
      //
      ASSERT (FALSE);
      return;
    }
  } else {
    //
    // The LMFA feature is enabled as load module at fixed offset relative to TOLM
    // Parse the Hob list to find the topest available memory. Generally it is (TOLM - TSEG)
    //
    //
    // Search for a tested memory region that is below MAX_ADDRESS
    //
    for (Hob.Raw = PrivateData->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
      //
      // See if this is a resource descriptor HOB
      //
      if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_RESOURCE_DESCRIPTOR) {

        ResourceHob = Hob.ResourceDescriptor;
        //
        // See if this resource descrior HOB describes tested system memory below MAX_ADDRESS
        //
        if (ResourceHob->ResourceType == EFI_RESOURCE_SYSTEM_MEMORY &&
            ResourceHob->PhysicalStart + ResourceHob->ResourceLength <= MAX_ADDRESS &&
            ResourceHob->ResourceLength > TotalReservedMemorySize && PeiLoadFixAddressIsMemoryRangeAvailable(PrivateData, ResourceHob)) {
          //
          // See if this is the highest largest system memory region below MaxAddress
          //
          if (ResourceHob->PhysicalStart > HighAddress) {
             CurrentResourceHob = ResourceHob;
             CurrentHob = Hob;
             HighAddress = CurrentResourceHob->PhysicalStart;
          }
        }
      }
    }
    if (CurrentResourceHob == NULL) {
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED ERROR:The System Memory is too small\n"));
      //
      // Assert here
      //
      ASSERT (FALSE);
      return;
    } else {
      TopLoadingAddress = CurrentResourceHob->PhysicalStart + CurrentResourceHob->ResourceLength ;
    }
  }

  if (CurrentResourceHob != NULL) {
    //
    // rebuild resource HOB for PEI memmory and reserved memory
    //
    BuildResourceDescriptorHob (
      EFI_RESOURCE_SYSTEM_MEMORY,
      (
      EFI_RESOURCE_ATTRIBUTE_PRESENT |
      EFI_RESOURCE_ATTRIBUTE_INITIALIZED |
      EFI_RESOURCE_ATTRIBUTE_TESTED |
      EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE |
      EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE |
      EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE |
      EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE
      ),
      (TopLoadingAddress - TotalReservedMemorySize),
      TotalReservedMemorySize
    );
    //
    // rebuild resource for the remain memory if necessary
    //
    if (CurrentResourceHob->PhysicalStart < TopLoadingAddress - TotalReservedMemorySize) {
      BuildResourceDescriptorHob (
        EFI_RESOURCE_SYSTEM_MEMORY,
        (
         EFI_RESOURCE_ATTRIBUTE_PRESENT |
         EFI_RESOURCE_ATTRIBUTE_INITIALIZED |
         EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE
         ),
         CurrentResourceHob->PhysicalStart,
         (TopLoadingAddress - TotalReservedMemorySize - CurrentResourceHob->PhysicalStart)
       );
    }
    if (CurrentResourceHob->PhysicalStart + CurrentResourceHob->ResourceLength  > TopLoadingAddress ) {
      BuildResourceDescriptorHob (
        EFI_RESOURCE_SYSTEM_MEMORY,
        (
         EFI_RESOURCE_ATTRIBUTE_PRESENT |
         EFI_RESOURCE_ATTRIBUTE_INITIALIZED |
         EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE |
         EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE
         ),
         TopLoadingAddress,
         (CurrentResourceHob->PhysicalStart + CurrentResourceHob->ResourceLength  - TopLoadingAddress)
       );
    }
    //
    // Delete CurrentHob by marking it as unused since the the memory range described by is rebuilt.
    //
    GET_HOB_TYPE (CurrentHob) = EFI_HOB_TYPE_UNUSED;
  }

  //
  // Cache the top address for Loading Module at Fixed Address feature
  //
  PrivateData->LoadModuleAtFixAddressTopAddress = TopLoadingAddress - MINIMUM_INITIAL_MEMORY_SIZE;
  DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: Top address = 0x%lx\n",  PrivateData->LoadModuleAtFixAddressTopAddress));
  //
  // reinstall the PEI memory relative to TopLoadingAddress
  //
  PrivateData->PhysicalMemoryBegin   = TopLoadingAddress - TotalReservedMemorySize;
  PrivateData->FreePhysicalMemoryTop = PrivateData->PhysicalMemoryBegin + PeiMemorySize;
}

/**
  This routine is invoked in switch stack as PeiCore Entry.

  @param SecCoreData     Points to a data structure containing information about the PEI core's operating
                         environment, such as the size and location of temporary RAM, the stack location and
                         the BFV location.
  @param Private         Pointer to old core data that is used to initialize the
                         core's data areas.
**/
VOID
EFIAPI
PeiCoreEntry (
  IN CONST EFI_SEC_PEI_HAND_OFF    *SecCoreData,
  IN PEI_CORE_INSTANCE             *Private
  )
{
  //
  // Entry PEI Phase 2
  //
  PeiCore (SecCoreData, NULL, Private);
}

/**
  Check SwitchStackSignal and switch stack if SwitchStackSignal is TRUE.

  @param[in] SecCoreData    Points to a data structure containing information about the PEI core's operating
                            environment, such as the size and location of temporary RAM, the stack location and
                            the BFV location.
  @param[in] Private        Pointer to the private data passed in from caller.

**/
VOID
PeiCheckAndSwitchStack (
  IN CONST EFI_SEC_PEI_HAND_OFF         *SecCoreData,
  IN PEI_CORE_INSTANCE                  *Private
  )
{
  VOID                                  *LoadFixPeiCodeBegin;
  EFI_STATUS                            Status;
  CONST EFI_PEI_SERVICES                **PeiServices;
  UINT64                                NewStackSize;
  EFI_PHYSICAL_ADDRESS                  TopOfOldStack;
  EFI_PHYSICAL_ADDRESS                  TopOfNewStack;
  UINTN                                 StackOffset;
  BOOLEAN                               StackOffsetPositive;
  EFI_PHYSICAL_ADDRESS                  TemporaryRamBase;
  UINTN                                 TemporaryRamSize;
  UINTN                                 TemporaryStackSize;
  VOID                                  *TemporaryStackBase;
  UINTN                                 PeiTemporaryRamSize;
  VOID                                  *PeiTemporaryRamBase;
  EFI_PEI_TEMPORARY_RAM_SUPPORT_PPI     *TemporaryRamSupportPpi;
  EFI_PHYSICAL_ADDRESS                  BaseOfNewHeap;
  EFI_PHYSICAL_ADDRESS                  HoleMemBase;
  UINTN                                 HoleMemSize;
  UINTN                                 HeapTemporaryRamSize;
  EFI_PHYSICAL_ADDRESS                  TempBase1;
  UINTN                                 TempSize1;
  EFI_PHYSICAL_ADDRESS                  TempBase2;
  UINTN                                 TempSize2;
  UINTN                                 Index;

  PeiServices = (CONST EFI_PEI_SERVICES **) &Private->Ps;

  if (Private->SwitchStackSignal) {
    //
    // Before switch stack from temporary memory to permanent memory, calculate the heap and stack
    // usage in temporary memory for debugging.
    //
    DEBUG_CODE_BEGIN ();
      UINT32                *StackPointer;
      EFI_PEI_HOB_POINTERS  Hob;

      for (StackPointer = (UINT32*)SecCoreData->StackBase;
           (StackPointer < (UINT32*)((UINTN)SecCoreData->StackBase + SecCoreData->StackSize)) \
           && (*StackPointer == PcdGet32 (PcdInitValueInTempStack));
           StackPointer ++) {
      }

      DEBUG ((DEBUG_INFO, "Temp Stack : BaseAddress=0x%p Length=0x%X\n", SecCoreData->StackBase, (UINT32)SecCoreData->StackSize));
      DEBUG ((DEBUG_INFO, "Temp Heap  : BaseAddress=0x%p Length=0x%X\n", SecCoreData->PeiTemporaryRamBase, (UINT32)SecCoreData->PeiTemporaryRamSize));
      DEBUG ((DEBUG_INFO, "Total temporary memory:    %d bytes.\n", (UINT32)SecCoreData->TemporaryRamSize));
      DEBUG ((DEBUG_INFO, "  temporary memory stack ever used:       %d bytes.\n",
             (UINT32)(SecCoreData->StackSize - ((UINTN) StackPointer - (UINTN)SecCoreData->StackBase))
            ));
      DEBUG ((DEBUG_INFO, "  temporary memory heap used for HobList: %d bytes.\n",
             (UINT32)((UINTN)Private->HobList.HandoffInformationTable->EfiFreeMemoryBottom - (UINTN)Private->HobList.Raw)
            ));
      DEBUG ((DEBUG_INFO, "  temporary memory heap occupied by memory pages: %d bytes.\n",
             (UINT32)(UINTN)(Private->HobList.HandoffInformationTable->EfiMemoryTop - Private->HobList.HandoffInformationTable->EfiFreeMemoryTop)
            ));
      for (Hob.Raw = Private->HobList.Raw; !END_OF_HOB_LIST(Hob); Hob.Raw = GET_NEXT_HOB(Hob)) {
        if (GET_HOB_TYPE (Hob) == EFI_HOB_TYPE_MEMORY_ALLOCATION) {
          DEBUG ((DEBUG_INFO, "Memory Allocation 0x%08x 0x%0lx - 0x%0lx\n", \
            Hob.MemoryAllocation->AllocDescriptor.MemoryType,               \
            Hob.MemoryAllocation->AllocDescriptor.MemoryBaseAddress,        \
            Hob.MemoryAllocation->AllocDescriptor.MemoryBaseAddress + Hob.MemoryAllocation->AllocDescriptor.MemoryLength - 1));
        }
      }
    DEBUG_CODE_END ();

    if (PcdGet64(PcdLoadModuleAtFixAddressEnable) != 0 && (Private->HobList.HandoffInformationTable->BootMode != BOOT_ON_S3_RESUME)) {
      //
      // Loading Module at Fixed Address is enabled
      //
      PeiLoadFixAddressHook (Private);

      //
      // If Loading Module at Fixed Address is enabled, Allocating memory range for Pei code range.
      //
      LoadFixPeiCodeBegin = AllocatePages((UINTN)PcdGet32(PcdLoadFixAddressPeiCodePageNumber));
      DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: PeiCodeBegin = 0x%lX, PeiCodeTop= 0x%lX\n", (UINT64)(UINTN)LoadFixPeiCodeBegin, (UINT64)((UINTN)LoadFixPeiCodeBegin + PcdGet32(PcdLoadFixAddressPeiCodePageNumber) * EFI_PAGE_SIZE)));
    }

    //
    // Reserve the size of new stack at bottom of physical memory
    //
    // The size of new stack in permanent memory must be the same size
    // or larger than the size of old stack in temporary memory.
    // But if new stack is smaller than the size of old stack, we also reserve
    // the size of old stack at bottom of permanent memory.
    //
    NewStackSize = RShiftU64 (Private->PhysicalMemoryLength, 1);
    NewStackSize = ALIGN_VALUE (NewStackSize, EFI_PAGE_SIZE);
    NewStackSize = MIN (PcdGet32(PcdPeiCoreMaxPeiStackSize), NewStackSize);
    DEBUG ((EFI_D_INFO, "Old Stack size %d, New stack size %d\n", (UINT32)SecCoreData->StackSize, (UINT32)NewStackSize));
    ASSERT (NewStackSize >= SecCoreData->StackSize);

    //
    // Calculate stack offset and heap offset between temporary memory and new permement
    // memory seperately.
    //
    TopOfOldStack = (UINTN)SecCoreData->StackBase + SecCoreData->StackSize;
    TopOfNewStack = Private->PhysicalMemoryBegin + NewStackSize;
    if (TopOfNewStack >= TopOfOldStack) {
      StackOffsetPositive = TRUE;
      StackOffset = (UINTN)(TopOfNewStack - TopOfOldStack);
    } else {
      StackOffsetPositive = FALSE;
      StackOffset = (UINTN)(TopOfOldStack - TopOfNewStack);
    }
    Private->StackOffsetPositive = StackOffsetPositive;
    Private->StackOffset = StackOffset;

    //
    // Build Stack HOB that describes the permanent memory stack
    //
    DEBUG ((EFI_D_INFO, "Stack Hob: BaseAddress=0x%lX Length=0x%lX\n", TopOfNewStack - NewStackSize, NewStackSize));
    BuildStackHob (TopOfNewStack - NewStackSize, NewStackSize);

    //
    // Cache information from SecCoreData into locals before SecCoreData is converted to a permanent memory address
    //
    TemporaryRamBase    = (EFI_PHYSICAL_ADDRESS)(UINTN)SecCoreData->TemporaryRamBase;
    TemporaryRamSize    = SecCoreData->TemporaryRamSize;
    TemporaryStackSize  = SecCoreData->StackSize;
    TemporaryStackBase  = SecCoreData->StackBase;
    PeiTemporaryRamSize = SecCoreData->PeiTemporaryRamSize;
    PeiTemporaryRamBase = SecCoreData->PeiTemporaryRamBase;

    //
    // TemporaryRamSupportPpi is produced by platform's SEC
    //
    Status = PeiServicesLocatePpi (
               &gEfiTemporaryRamSupportPpiGuid,
               0,
               NULL,
               (VOID**)&TemporaryRamSupportPpi
               );
    if (!EFI_ERROR (Status)) {
      //
      // Heap Offset
      //
      BaseOfNewHeap = TopOfNewStack;
      if (BaseOfNewHeap >= (UINTN)SecCoreData->PeiTemporaryRamBase) {
        Private->HeapOffsetPositive = TRUE;
        Private->HeapOffset = (UINTN)(BaseOfNewHeap - (UINTN)SecCoreData->PeiTemporaryRamBase);
      } else {
        Private->HeapOffsetPositive = FALSE;
        Private->HeapOffset = (UINTN)((UINTN)SecCoreData->PeiTemporaryRamBase - BaseOfNewHeap);
      }

      DEBUG ((EFI_D_INFO, "Heap Offset = 0x%lX Stack Offset = 0x%lX\n", (UINT64) Private->HeapOffset, (UINT64) Private->StackOffset));

      //
      // Calculate new HandOffTable and PrivateData address in permanent memory's stack
      //
      if (StackOffsetPositive) {
        SecCoreData = (CONST EFI_SEC_PEI_HAND_OFF *)((UINTN)(VOID *)SecCoreData + StackOffset);
        Private = (PEI_CORE_INSTANCE *)((UINTN)(VOID *)Private + StackOffset);
      } else {
        SecCoreData = (CONST EFI_SEC_PEI_HAND_OFF *)((UINTN)(VOID *)SecCoreData - StackOffset);
        Private = (PEI_CORE_INSTANCE *)((UINTN)(VOID *)Private - StackOffset);
      }

      //
      // Temporary Ram Support PPI is provided by platform, it will copy
      // temporary memory to permanent memory and do stack switching.
      // After invoking Temporary Ram Support PPI, the following code's
      // stack is in permanent memory.
      //
      TemporaryRamSupportPpi->TemporaryRamMigration (
                                PeiServices,
                                TemporaryRamBase,
                                (EFI_PHYSICAL_ADDRESS)(UINTN)(TopOfNewStack - TemporaryStackSize),
                                TemporaryRamSize
                                );

      //
      // Migrate memory pages allocated in pre-memory phase.
      // It could not be called before calling TemporaryRamSupportPpi->TemporaryRamMigration()
      // as the migrated memory pages may be overridden by TemporaryRamSupportPpi->TemporaryRamMigration().
      //
      MigrateMemoryPages (Private, TRUE);

      //
      // Entry PEI Phase 2
      //
      PeiCore (SecCoreData, NULL, Private);
    } else {
      //
      // Migrate memory pages allocated in pre-memory phase.
      //
      MigrateMemoryPages (Private, FALSE);

      //
      // Migrate the PEI Services Table pointer from temporary RAM to permanent RAM.
      //
      MigratePeiServicesTablePointer ();

      //
      // Heap Offset
      //
      BaseOfNewHeap = TopOfNewStack;
      HoleMemBase   = TopOfNewStack;
      HoleMemSize   = TemporaryRamSize - PeiTemporaryRamSize - TemporaryStackSize;
      if (HoleMemSize != 0) {
        //
        // Make sure HOB List start address is 8 byte alignment.
        //
        BaseOfNewHeap = ALIGN_VALUE (BaseOfNewHeap + HoleMemSize, 8);
      }
      if (BaseOfNewHeap >= (UINTN)SecCoreData->PeiTemporaryRamBase) {
        Private->HeapOffsetPositive = TRUE;
        Private->HeapOffset = (UINTN)(BaseOfNewHeap - (UINTN)SecCoreData->PeiTemporaryRamBase);
      } else {
        Private->HeapOffsetPositive = FALSE;
        Private->HeapOffset = (UINTN)((UINTN)SecCoreData->PeiTemporaryRamBase - BaseOfNewHeap);
      }

      DEBUG ((EFI_D_INFO, "Heap Offset = 0x%lX Stack Offset = 0x%lX\n", (UINT64) Private->HeapOffset, (UINT64) Private->StackOffset));

      //
      // Migrate Heap
      //
      HeapTemporaryRamSize = (UINTN) (Private->HobList.HandoffInformationTable->EfiFreeMemoryBottom - Private->HobList.HandoffInformationTable->EfiMemoryBottom);
      ASSERT (BaseOfNewHeap + HeapTemporaryRamSize <= Private->FreePhysicalMemoryTop);
      CopyMem ((UINT8 *) (UINTN) BaseOfNewHeap, PeiTemporaryRamBase, HeapTemporaryRamSize);

      //
      // Migrate Stack
      //
      CopyMem ((UINT8 *) (UINTN) (TopOfNewStack - TemporaryStackSize), TemporaryStackBase, TemporaryStackSize);

      //
      // Copy Hole Range Data
      //
      if (HoleMemSize != 0) {
        //
        // Prepare Hole
        //
        if (PeiTemporaryRamBase < TemporaryStackBase) {
          TempBase1 = (EFI_PHYSICAL_ADDRESS) (UINTN) PeiTemporaryRamBase;
          TempSize1 = PeiTemporaryRamSize;
          TempBase2 = (EFI_PHYSICAL_ADDRESS) (UINTN) TemporaryStackBase;
          TempSize2 = TemporaryStackSize;
        } else {
          TempBase1 = (EFI_PHYSICAL_ADDRESS) (UINTN) TemporaryStackBase;
          TempSize1 = TemporaryStackSize;
          TempBase2 =(EFI_PHYSICAL_ADDRESS) (UINTN) PeiTemporaryRamBase;
          TempSize2 = PeiTemporaryRamSize;
        }
        if (TemporaryRamBase < TempBase1) {
          Private->HoleData[0].Base = TemporaryRamBase;
          Private->HoleData[0].Size = (UINTN) (TempBase1 - TemporaryRamBase);
        }
        if (TempBase1 + TempSize1 < TempBase2) {
          Private->HoleData[1].Base = TempBase1 + TempSize1;
          Private->HoleData[1].Size = (UINTN) (TempBase2 - TempBase1 - TempSize1);
        }
        if (TempBase2 + TempSize2 < TemporaryRamBase + TemporaryRamSize) {
          Private->HoleData[2].Base = TempBase2 + TempSize2;
          Private->HoleData[2].Size = (UINTN) (TemporaryRamBase + TemporaryRamSize - TempBase2 - TempSize2);
        }

        //
        // Copy Hole Range data.
        //
        for (Index = 0; Index < HOLE_MAX_NUMBER; Index ++) {
          if (Private->HoleData[Index].Size > 0) {
            if (HoleMemBase > Private->HoleData[Index].Base) {
              Private->HoleData[Index].OffsetPositive = TRUE;
              Private->HoleData[Index].Offset = (UINTN) (HoleMemBase - Private->HoleData[Index].Base);
            } else {
              Private->HoleData[Index].OffsetPositive = FALSE;
              Private->HoleData[Index].Offset = (UINTN) (Private->HoleData[Index].Base - HoleMemBase);
            }
            CopyMem ((VOID *) (UINTN) HoleMemBase, (VOID *) (UINTN) Private->HoleData[Index].Base, Private->HoleData[Index].Size);
            HoleMemBase = HoleMemBase + Private->HoleData[Index].Size;
          }
        }
      }

      //
      // Switch new stack
      //
      SwitchStack (
        (SWITCH_STACK_ENTRY_POINT)(UINTN)PeiCoreEntry,
        (VOID *) SecCoreData,
        (VOID *) Private,
        (VOID *) (UINTN) TopOfNewStack
        );
    }

    //
    // Code should not come here
    //
    ASSERT (FALSE);
  }
}

/**
  Conduct PEIM dispatch.

  @param SecCoreData     Points to a data structure containing information about the PEI core's operating
                         environment, such as the size and location of temporary RAM, the stack location and
                         the BFV location.
  @param Private         Pointer to the private data passed in from caller

**/
VOID
PeiDispatcher (
  IN CONST EFI_SEC_PEI_HAND_OFF  *SecCoreData,
  IN PEI_CORE_INSTANCE           *Private
  )
{
  EFI_STATUS                          Status;
  UINT32                              Index1;
  UINT32                              Index2;
  CONST EFI_PEI_SERVICES              **PeiServices;
  EFI_PEI_FILE_HANDLE                 PeimFileHandle;
  UINTN                               FvCount;
  UINTN                               PeimCount;
  UINT32                              AuthenticationState;
  EFI_PHYSICAL_ADDRESS                EntryPoint;
  EFI_PEIM_ENTRY_POINT2               PeimEntryPoint;
  UINTN                               SaveCurrentPeimCount;
  UINTN                               SaveCurrentFvCount;
  EFI_PEI_FILE_HANDLE                 SaveCurrentFileHandle;
  EFI_FV_FILE_INFO                    FvFileInfo;
  PEI_CORE_FV_HANDLE                  *CoreFvHandle;

  PeiServices = (CONST EFI_PEI_SERVICES **) &Private->Ps;
  PeimEntryPoint = NULL;
  PeimFileHandle = NULL;
  EntryPoint     = 0;

  if ((Private->PeiMemoryInstalled) && (Private->HobList.HandoffInformationTable->BootMode != BOOT_ON_S3_RESUME || PcdGetBool (PcdShadowPeimOnS3Boot))) {
    //
    // Once real memory is available, shadow the RegisterForShadow modules. And meanwhile
    // update the modules' status from PEIM_STATE_REGISTER_FOR_SHADOW to PEIM_STATE_DONE.
    //
    SaveCurrentPeimCount  = Private->CurrentPeimCount;
    SaveCurrentFvCount    = Private->CurrentPeimFvCount;
    SaveCurrentFileHandle =  Private->CurrentFileHandle;

    for (Index1 = 0; Index1 < Private->FvCount; Index1++) {
      for (Index2 = 0; Index2 < Private->Fv[Index1].PeimCount; Index2++) {
        if (Private->Fv[Index1].PeimState[Index2] == PEIM_STATE_REGISTER_FOR_SHADOW) {
          PeimFileHandle = Private->Fv[Index1].FvFileHandles[Index2];
          Private->CurrentFileHandle   = PeimFileHandle;
          Private->CurrentPeimFvCount  = Index1;
          Private->CurrentPeimCount    = Index2;
          Status = PeiLoadImage (
                    (CONST EFI_PEI_SERVICES **) &Private->Ps,
                    PeimFileHandle,
                    PEIM_STATE_REGISTER_FOR_SHADOW,
                    &EntryPoint,
                    &AuthenticationState
                    );
          if (Status == EFI_SUCCESS) {
            //
            // PEIM_STATE_REGISTER_FOR_SHADOW move to PEIM_STATE_DONE
            //
            Private->Fv[Index1].PeimState[Index2]++;
            //
            // Call the PEIM entry point
            //
            PeimEntryPoint = (EFI_PEIM_ENTRY_POINT2)(UINTN)EntryPoint;

            PERF_START_IMAGE_BEGIN (PeimFileHandle);
            PeimEntryPoint(PeimFileHandle, (const EFI_PEI_SERVICES **) &Private->Ps);
            PERF_START_IMAGE_END (PeimFileHandle);
          }

          //
          // Process the Notify list and dispatch any notifies for
          // newly installed PPIs.
          //
          ProcessDispatchNotifyList (Private);
        }
      }
    }
    Private->CurrentFileHandle  = SaveCurrentFileHandle;
    Private->CurrentPeimFvCount = SaveCurrentFvCount;
    Private->CurrentPeimCount   = SaveCurrentPeimCount;
  }

  //
  // This is the main dispatch loop.  It will search known FVs for PEIMs and
  // attempt to dispatch them.  If any PEIM gets dispatched through a single
  // pass of the dispatcher, it will start over from the Bfv again to see
  // if any new PEIMs dependencies got satisfied.  With a well ordered
  // FV where PEIMs are found in the order their dependencies are also
  // satisfied, this dipatcher should run only once.
  //
  do {
    //
    // In case that reenter PeiCore happens, the last pass record is still available.
    //
    if (!Private->PeimDispatcherReenter) {
      Private->PeimNeedingDispatch      = FALSE;
      Private->PeimDispatchOnThisPass   = FALSE;
    } else {
      Private->PeimDispatcherReenter    = FALSE;
    }

    for (FvCount = Private->CurrentPeimFvCount; FvCount < Private->FvCount; FvCount++) {
      CoreFvHandle = FindNextCoreFvHandle (Private, FvCount);
      ASSERT (CoreFvHandle != NULL);

      //
      // If the FV has corresponding EFI_PEI_FIRMWARE_VOLUME_PPI instance, then dispatch it.
      //
      if (CoreFvHandle->FvPpi == NULL) {
        continue;
      }

      Private->CurrentPeimFvCount = FvCount;

      if (Private->CurrentPeimCount == 0) {
        //
        // When going through each FV, at first, search Apriori file to
        // reorder all PEIMs to ensure the PEIMs in Apriori file to get
        // dispatch at first.
        //
        DiscoverPeimsAndOrderWithApriori (Private, CoreFvHandle);
      }

      //
      // Start to dispatch all modules within the current Fv.
      //
      for (PeimCount = Private->CurrentPeimCount;
           PeimCount < Private->Fv[FvCount].PeimCount;
           PeimCount++) {
        Private->CurrentPeimCount  = PeimCount;
        PeimFileHandle = Private->CurrentFileHandle = Private->CurrentFvFileHandles[PeimCount];

        if (Private->Fv[FvCount].PeimState[PeimCount] == PEIM_STATE_NOT_DISPATCHED) {
          if (!DepexSatisfied (Private, PeimFileHandle, PeimCount)) {
            Private->PeimNeedingDispatch = TRUE;
          } else {
            Status = CoreFvHandle->FvPpi->GetFileInfo (CoreFvHandle->FvPpi, PeimFileHandle, &FvFileInfo);
            ASSERT_EFI_ERROR (Status);
            if (FvFileInfo.FileType == EFI_FV_FILETYPE_FIRMWARE_VOLUME_IMAGE) {
              //
              // For Fv type file, Produce new FvInfo PPI and FV hob
              //
              Status = ProcessFvFile (Private, &Private->Fv[FvCount], PeimFileHandle);
              if (Status == EFI_SUCCESS) {
                //
                // PEIM_STATE_NOT_DISPATCHED move to PEIM_STATE_DISPATCHED
                //
                Private->Fv[FvCount].PeimState[PeimCount]++;
                Private->PeimDispatchOnThisPass = TRUE;
              } else {
                //
                // The related GuidedSectionExtraction/Decompress PPI for the
                // encapsulated FV image section may be installed in the rest
                // of this do-while loop, so need to make another pass.
                //
                Private->PeimNeedingDispatch = TRUE;
              }
            } else {
              //
              // For PEIM driver, Load its entry point
              //
              Status = PeiLoadImage (
                         PeiServices,
                         PeimFileHandle,
                         PEIM_STATE_NOT_DISPATCHED,
                         &EntryPoint,
                         &AuthenticationState
                         );
              if (Status == EFI_SUCCESS) {
                //
                // The PEIM has its dependencies satisfied, and its entry point
                // has been found, so invoke it.
                //
                PERF_START_IMAGE_BEGIN (PeimFileHandle);

                REPORT_STATUS_CODE_WITH_EXTENDED_DATA (
                  EFI_PROGRESS_CODE,
                  (EFI_SOFTWARE_PEI_CORE | EFI_SW_PC_INIT_BEGIN),
                  (VOID *)(&PeimFileHandle),
                  sizeof (PeimFileHandle)
                  );

                Status = VerifyPeim (Private, CoreFvHandle->FvHandle, PeimFileHandle, AuthenticationState);
                if (Status != EFI_SECURITY_VIOLATION) {
                  //
                  // PEIM_STATE_NOT_DISPATCHED move to PEIM_STATE_DISPATCHED
                  //
                  Private->Fv[FvCount].PeimState[PeimCount]++;
                  //
                  // Call the PEIM entry point for PEIM driver
                  //
                  PeimEntryPoint = (EFI_PEIM_ENTRY_POINT2)(UINTN)EntryPoint;
                  PeimEntryPoint (PeimFileHandle, (const EFI_PEI_SERVICES **) PeiServices);
                  Private->PeimDispatchOnThisPass = TRUE;
                } else {
                  //
                  // The related GuidedSectionExtraction PPI for the
                  // signed PEIM image section may be installed in the rest
                  // of this do-while loop, so need to make another pass.
                  //
                  Private->PeimNeedingDispatch = TRUE;
                }

                REPORT_STATUS_CODE_WITH_EXTENDED_DATA (
                  EFI_PROGRESS_CODE,
                  (EFI_SOFTWARE_PEI_CORE | EFI_SW_PC_INIT_END),
                  (VOID *)(&PeimFileHandle),
                  sizeof (PeimFileHandle)
                  );
                PERF_START_IMAGE_END (PeimFileHandle);

              }
            }

            PeiCheckAndSwitchStack (SecCoreData, Private);

            //
            // Process the Notify list and dispatch any notifies for
            // newly installed PPIs.
            //
            ProcessDispatchNotifyList (Private);

            //
            // Recheck SwitchStackSignal after ProcessDispatchNotifyList()
            // in case PeiInstallPeiMemory() is done in a callback with
            // EFI_PEI_PPI_DESCRIPTOR_NOTIFY_DISPATCH.
            //
            PeiCheckAndSwitchStack (SecCoreData, Private);

            if ((Private->PeiMemoryInstalled) && (Private->Fv[FvCount].PeimState[PeimCount] == PEIM_STATE_REGISTER_FOR_SHADOW) &&   \
                (Private->HobList.HandoffInformationTable->BootMode != BOOT_ON_S3_RESUME || PcdGetBool (PcdShadowPeimOnS3Boot))) {
              //
              // If memory is available we shadow images by default for performance reasons.
              // We call the entry point a 2nd time so the module knows it's shadowed.
              //
              //PERF_START (PeiServices, L"PEIM", PeimFileHandle, 0);
              if ((Private->HobList.HandoffInformationTable->BootMode != BOOT_ON_S3_RESUME) && !PcdGetBool (PcdShadowPeimOnBoot)) {
                //
                // Load PEIM into Memory for Register for shadow PEIM.
                //
                Status = PeiLoadImage (
                           PeiServices,
                           PeimFileHandle,
                           PEIM_STATE_REGISTER_FOR_SHADOW,
                           &EntryPoint,
                           &AuthenticationState
                           );
                if (Status == EFI_SUCCESS) {
                  PeimEntryPoint = (EFI_PEIM_ENTRY_POINT2)(UINTN)EntryPoint;
                }
              }
              ASSERT (PeimEntryPoint != NULL);
              PeimEntryPoint (PeimFileHandle, (const EFI_PEI_SERVICES **) PeiServices);
              //PERF_END (PeiServices, L"PEIM", PeimFileHandle, 0);

              //
              // PEIM_STATE_REGISTER_FOR_SHADOW move to PEIM_STATE_DONE
              //
              Private->Fv[FvCount].PeimState[PeimCount]++;

              //
              // Process the Notify list and dispatch any notifies for
              // newly installed PPIs.
              //
              ProcessDispatchNotifyList (Private);
            }
          }
        }
      }

      //
      // Before walking through the next FV, we should set them to NULL/0 to
      // start at the begining of the next FV.
      //
      Private->CurrentFileHandle = NULL;
      Private->CurrentPeimCount = 0;
      Private->CurrentFvFileHandles = NULL;
    }

    //
    // Before making another pass, we should set it to 0 to
    // go through all the FVs.
    //
    Private->CurrentPeimFvCount = 0;

    //
    // PeimNeedingDispatch being TRUE means we found a PEIM/FV that did not get
    //  dispatched. So we need to make another pass
    //
    // PeimDispatchOnThisPass being TRUE means we dispatched a PEIM/FV on this
    //  pass. If we did not dispatch a PEIM/FV there is no point in trying again
    //  as it will fail the next time too (nothing has changed).
    //
  } while (Private->PeimNeedingDispatch && Private->PeimDispatchOnThisPass);

}

/**
  Initialize the Dispatcher's data members

  @param PrivateData     PeiCore's private data structure
  @param OldCoreData     Old data from SecCore
                         NULL if being run in non-permament memory mode.
  @param SecCoreData     Points to a data structure containing information about the PEI core's operating
                         environment, such as the size and location of temporary RAM, the stack location and
                         the BFV location.

  @return None.

**/
VOID
InitializeDispatcherData (
  IN PEI_CORE_INSTANCE            *PrivateData,
  IN PEI_CORE_INSTANCE            *OldCoreData,
  IN CONST EFI_SEC_PEI_HAND_OFF   *SecCoreData
  )
{
  if (OldCoreData == NULL) {
    PrivateData->PeimDispatcherReenter = FALSE;
    PeiInitializeFv (PrivateData, SecCoreData);
  } else {
    PeiReinitializeFv (PrivateData);
  }

  return;
}

/**
  This routine parses the Dependency Expression, if available, and
  decides if the module can be executed.


  @param Private         PeiCore's private data structure
  @param FileHandle      PEIM's file handle
  @param PeimCount       Peim count in all dispatched PEIMs.

  @retval TRUE   Can be dispatched
  @retval FALSE  Cannot be dispatched

**/
BOOLEAN
DepexSatisfied (
  IN PEI_CORE_INSTANCE          *Private,
  IN EFI_PEI_FILE_HANDLE        FileHandle,
  IN UINTN                      PeimCount
  )
{
  EFI_STATUS           Status;
  VOID                 *DepexData;
  EFI_FV_FILE_INFO     FileInfo;

  Status = PeiServicesFfsGetFileInfo (FileHandle, &FileInfo);
  if (EFI_ERROR (Status)) {
    DEBUG ((DEBUG_DISPATCH, "Evaluate PEI DEPEX for FFS(Unknown)\n"));
  } else {
    DEBUG ((DEBUG_DISPATCH, "Evaluate PEI DEPEX for FFS(%g)\n", &FileInfo.FileName));
  }

  if (PeimCount < Private->AprioriCount) {
    //
    // If it's in the Apriori file then we set Depex to TRUE
    //
    DEBUG ((DEBUG_DISPATCH, "  RESULT = TRUE (Apriori)\n"));
    return TRUE;
  }

  //
  // Depex section not in the encapsulated section.
  //
  Status = PeiServicesFfsFindSectionData (
              EFI_SECTION_PEI_DEPEX,
              FileHandle,
              (VOID **)&DepexData
              );

  if (EFI_ERROR (Status)) {
    //
    // If there is no DEPEX, assume the module can be executed
    //
    DEBUG ((DEBUG_DISPATCH, "  RESULT = TRUE (No DEPEX)\n"));
    return TRUE;
  }

  //
  // Evaluate a given DEPEX
  //
  return PeimDispatchReadiness (&Private->Ps, DepexData);
}

/**
  This routine enable a PEIM to register itself to shadow when PEI Foundation
  discovery permanent memory.

  @param FileHandle             File handle of a PEIM.

  @retval EFI_NOT_FOUND         The file handle doesn't point to PEIM itself.
  @retval EFI_ALREADY_STARTED   Indicate that the PEIM has been registered itself.
  @retval EFI_SUCCESS           Successfully to register itself.

**/
EFI_STATUS
EFIAPI
PeiRegisterForShadow (
  IN EFI_PEI_FILE_HANDLE       FileHandle
  )
{
  PEI_CORE_INSTANCE            *Private;
  Private = PEI_CORE_INSTANCE_FROM_PS_THIS (GetPeiServicesTablePointer ());

  if (Private->CurrentFileHandle != FileHandle) {
    //
    // The FileHandle must be for the current PEIM
    //
    return EFI_NOT_FOUND;
  }

  if (Private->Fv[Private->CurrentPeimFvCount].PeimState[Private->CurrentPeimCount] >= PEIM_STATE_REGISTER_FOR_SHADOW) {
    //
    // If the PEIM has already entered the PEIM_STATE_REGISTER_FOR_SHADOW or PEIM_STATE_DONE then it's already been started
    //
    return EFI_ALREADY_STARTED;
  }

  Private->Fv[Private->CurrentPeimFvCount].PeimState[Private->CurrentPeimCount] = PEIM_STATE_REGISTER_FOR_SHADOW;

  return EFI_SUCCESS;
}



