audk/IntelFspPkg/FspSecCore/SecMain.c

/** @file

  Copyright (c) 2014 - 2015, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "SecMain.h"
#include "SecFsp.h"

EFI_PEI_TEMPORARY_RAM_SUPPORT_PPI gSecTemporaryRamSupportPpi = {
  SecTemporaryRamSupport
};

EFI_PEI_PPI_DESCRIPTOR            mPeiSecPlatformInformationPpi[] = {
  {
    (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
    &gEfiTemporaryRamSupportPpiGuid,
    &gSecTemporaryRamSupportPpi
  }
};

//
// These are IDT entries pointing to 08:FFFFFFE4h.
//
UINT64  mIdtEntryTemplate = 0xffff8e000008ffe4ULL;

/**

  Entry point to the C language phase of SEC. After the SEC assembly
  code has initialized some temporary memory and set up the stack,
  the control is transferred to this function.


  @param[in] SizeOfRam          Size of the temporary memory available for use.
  @param[in] TempRamBase        Base address of temporary ram
  @param[in] BootFirmwareVolume Base address of the Boot Firmware Volume.
  @param[in] PeiCore            PeiCore entry point.
  @param[in] BootLoaderStack    BootLoader stack.
  @param[in] ApiIdx             the index of API.

  @return This function never returns.

**/
VOID
EFIAPI
SecStartup (
  IN UINT32                   SizeOfRam,
  IN UINT32                   TempRamBase,
  IN VOID                    *BootFirmwareVolume,
  IN PEI_CORE_ENTRY           PeiCore,
  IN UINT32                   BootLoaderStack,
  IN UINT32                   ApiIdx
  )
{
  EFI_SEC_PEI_HAND_OFF        SecCoreData;
  IA32_DESCRIPTOR             IdtDescriptor;
  SEC_IDT_TABLE               IdtTableInStack;
  UINT32                      Index;
  FSP_GLOBAL_DATA             PeiFspData;
  UINT64                      ExceptionHandler;

  //
  // Process all libraries constructor function linked to SecCore.
  //
  ProcessLibraryConstructorList ();

  //
  // Initialize floating point operating environment
  // to be compliant with UEFI spec.
  //
  InitializeFloatingPointUnits ();


  // |-------------------|---->
  // |Idt Table          |
  // |-------------------|
  // |PeiService Pointer |    PeiStackSize
  // |-------------------|
  // |                   |
  // |      Stack        |
  // |-------------------|---->
  // |                   |
  // |                   |
  // |      Heap         |    PeiTemporayRamSize
  // |                   |
  // |                   |
  // |-------------------|---->  TempRamBase
  IdtTableInStack.PeiService  = NULL;
  ExceptionHandler = FspGetExceptionHandler(mIdtEntryTemplate);
  for (Index = 0; Index < SEC_IDT_ENTRY_COUNT; Index ++) {
    CopyMem ((VOID*)&IdtTableInStack.IdtTable[Index], (VOID*)&ExceptionHandler, sizeof (UINT64));
  }

  IdtDescriptor.Base  = (UINTN) &IdtTableInStack.IdtTable;
  IdtDescriptor.Limit = (UINT16)(sizeof (IdtTableInStack.IdtTable) - 1);

  AsmWriteIdtr (&IdtDescriptor);

  //
  // Initialize the global FSP data region
  //
  FspGlobalDataInit (&PeiFspData, BootLoaderStack, (UINT8)ApiIdx);

  //
  // Update the base address and length of Pei temporary memory
  //
  SecCoreData.DataSize               = sizeof (EFI_SEC_PEI_HAND_OFF);
  SecCoreData.BootFirmwareVolumeBase = BootFirmwareVolume;
  SecCoreData.BootFirmwareVolumeSize = (UINT32)((EFI_FIRMWARE_VOLUME_HEADER *)BootFirmwareVolume)->FvLength;
  SecCoreData.TemporaryRamBase       = (VOID*)(UINTN) TempRamBase;
  SecCoreData.TemporaryRamSize       = SizeOfRam;
  SecCoreData.PeiTemporaryRamBase    = SecCoreData.TemporaryRamBase;
  SecCoreData.PeiTemporaryRamSize    = SizeOfRam >> 1;
  SecCoreData.StackBase              = (VOID*)(UINTN)(TempRamBase + SecCoreData.PeiTemporaryRamSize);
  SecCoreData.StackSize              = SizeOfRam >> 1;

  //
  // Call PeiCore Entry
  //  
  PeiCore (&SecCoreData, mPeiSecPlatformInformationPpi);

  //
  // Should never be here
  //
  CpuDeadLoop ();
}

/**
  This service of the TEMPORARY_RAM_SUPPORT_PPI that migrates temporary RAM into
  permanent memory.

  @param[in] PeiServices            Pointer to the PEI Services Table.
  @param[in] TemporaryMemoryBase    Source Address in temporary memory from which the SEC or PEIM will copy the
                                Temporary RAM contents.
  @param[in] PermanentMemoryBase    Destination Address in permanent memory into which the SEC or PEIM will copy the
                                Temporary RAM contents.
  @param[in] CopySize               Amount of memory to migrate from temporary to permanent memory.

  @retval EFI_SUCCESS           The data was successfully returned.
  @retval EFI_INVALID_PARAMETER PermanentMemoryBase + CopySize > TemporaryMemoryBase when
                                TemporaryMemoryBase > PermanentMemoryBase.

**/
EFI_STATUS
EFIAPI
SecTemporaryRamSupport (
  IN CONST EFI_PEI_SERVICES   **PeiServices,
  IN EFI_PHYSICAL_ADDRESS     TemporaryMemoryBase,
  IN EFI_PHYSICAL_ADDRESS     PermanentMemoryBase,
  IN UINTN                    CopySize
  )
{
  IA32_DESCRIPTOR   IdtDescriptor;
  VOID*             OldHeap;
  VOID*             NewHeap;
  VOID*             OldStack;
  VOID*             NewStack;

  OldHeap = (VOID*)(UINTN)TemporaryMemoryBase;
  NewHeap = (VOID*)((UINTN)PermanentMemoryBase + CopySize / 2);

  OldStack = (VOID*)((UINTN)TemporaryMemoryBase + CopySize / 2);
  NewStack = (VOID*)(UINTN)PermanentMemoryBase;

  //
  // Migrate Heap
  //
  CopyMem (NewHeap, OldHeap, CopySize / 2);

  //
  // Migrate Stack
  //
  CopyMem (NewStack, OldStack, CopySize / 2);


  //
  // We need *not* fix the return address because currently,
  // The PeiCore is executed in flash.
  //

  //
  // Rebase IDT table in permanent memory
  //
  AsmReadIdtr (&IdtDescriptor);
  IdtDescriptor.Base = IdtDescriptor.Base - (UINTN)OldStack + (UINTN)NewStack;

  AsmWriteIdtr (&IdtDescriptor);

  //
  // Fixed the FSP data pointer
  //
  FspDataPointerFixUp ((UINTN)NewStack - (UINTN)OldStack);

  //
  // SecSwitchStack function must be invoked after the memory migration
  // immediately, also we need fixup the stack change caused by new call into
  // permanent memory.
  //
  SecSwitchStack (
    (UINT32) (UINTN) OldStack,
    (UINT32) (UINTN) NewStack
    );

  return EFI_SUCCESS;
}