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/**@file
  Platform PEI driver

  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
  Copyright (c) 2011, Andrei Warkentin <andreiw@motorola.com>

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

//
// The package level header files this module uses
//
#include <PiPei.h>

//
// The Library classes this module consumes
//
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/HobLib.h>
#include <Library/IoLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/PcdLib.h>
#include <Library/PciLib.h>
#include <Library/PeimEntryPoint.h>
#include <Library/PeiServicesLib.h>
#include <Library/QemuFwCfgLib.h>
#include <Library/QemuFwCfgS3Lib.h>
#include <Library/ResourcePublicationLib.h>
#include <Guid/MemoryTypeInformation.h>
#include <Ppi/MasterBootMode.h>
#include <IndustryStandard/Pci22.h>
#include <OvmfPlatforms.h>

#include "Platform.h"
#include "Cmos.h"

EFI_MEMORY_TYPE_INFORMATION mDefaultMemoryTypeInformation[] = {
  { EfiACPIMemoryNVS,       0x004 },
  { EfiACPIReclaimMemory,   0x008 },
  { EfiReservedMemoryType,  0x004 },
  { EfiRuntimeServicesData, 0x024 },
  { EfiRuntimeServicesCode, 0x030 },
  { EfiBootServicesCode,    0x180 },
  { EfiBootServicesData,    0xF00 },
  { EfiMaxMemoryType,       0x000 }
};


EFI_PEI_PPI_DESCRIPTOR   mPpiBootMode[] = {
  {
    EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST,
    &gEfiPeiMasterBootModePpiGuid,
    NULL
  }
};


UINT16 mHostBridgeDevId;

EFI_BOOT_MODE mBootMode = BOOT_WITH_FULL_CONFIGURATION;

BOOLEAN mS3Supported = FALSE;

UINT32 mMaxCpuCount;

VOID
AddIoMemoryBaseSizeHob (
  EFI_PHYSICAL_ADDRESS        MemoryBase,
  UINT64                      MemorySize
  )
{
  BuildResourceDescriptorHob (
    EFI_RESOURCE_MEMORY_MAPPED_IO,
      EFI_RESOURCE_ATTRIBUTE_PRESENT     |
      EFI_RESOURCE_ATTRIBUTE_INITIALIZED |
      EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE |
      EFI_RESOURCE_ATTRIBUTE_TESTED,
    MemoryBase,
    MemorySize
    );
}

VOID
AddReservedMemoryBaseSizeHob (
  EFI_PHYSICAL_ADDRESS        MemoryBase,
  UINT64                      MemorySize,
  BOOLEAN                     Cacheable
  )
{
  BuildResourceDescriptorHob (
    EFI_RESOURCE_MEMORY_RESERVED,
      EFI_RESOURCE_ATTRIBUTE_PRESENT     |
      EFI_RESOURCE_ATTRIBUTE_INITIALIZED |
      EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE |
      (Cacheable ?
       EFI_RESOURCE_ATTRIBUTE_WRITE_COMBINEABLE |
       EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE |
       EFI_RESOURCE_ATTRIBUTE_WRITE_BACK_CACHEABLE :
       0
       ) |
      EFI_RESOURCE_ATTRIBUTE_TESTED,
    MemoryBase,
    MemorySize
    );
}

VOID
AddIoMemoryRangeHob (
  EFI_PHYSICAL_ADDRESS        MemoryBase,
  EFI_PHYSICAL_ADDRESS        MemoryLimit
  )
{
  AddIoMemoryBaseSizeHob (MemoryBase, (UINT64)(MemoryLimit - MemoryBase));
}


VOID
AddMemoryBaseSizeHob (
  EFI_PHYSICAL_ADDRESS        MemoryBase,
  UINT64                      MemorySize
  )
{
  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 |
      EFI_RESOURCE_ATTRIBUTE_TESTED,
    MemoryBase,
    MemorySize
    );
}


VOID
AddMemoryRangeHob (
  EFI_PHYSICAL_ADDRESS        MemoryBase,
  EFI_PHYSICAL_ADDRESS        MemoryLimit
  )
{
  AddMemoryBaseSizeHob (MemoryBase, (UINT64)(MemoryLimit - MemoryBase));
}


VOID
MemMapInitialization (
  VOID
  )
{
  UINT64        PciIoBase;
  UINT64        PciIoSize;
  RETURN_STATUS PcdStatus;

  PciIoBase = 0xC000;
  PciIoSize = 0x4000;

  //
  // Create Memory Type Information HOB
  //
  BuildGuidDataHob (
    &gEfiMemoryTypeInformationGuid,
    mDefaultMemoryTypeInformation,
    sizeof(mDefaultMemoryTypeInformation)
    );

  //
  // Video memory + Legacy BIOS region
  //
  AddIoMemoryRangeHob (0x0A0000, BASE_1MB);

  if (!mXen) {
    UINT32  TopOfLowRam;
    UINT64  PciExBarBase;
    UINT32  PciBase;
    UINT32  PciSize;

    TopOfLowRam = GetSystemMemorySizeBelow4gb ();
    PciExBarBase = 0;
    if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) {
      //
      // The MMCONFIG area is expected to fall between the top of low RAM and
      // the base of the 32-bit PCI host aperture.
      //
      PciExBarBase = FixedPcdGet64 (PcdPciExpressBaseAddress);
      ASSERT (TopOfLowRam <= PciExBarBase);
      ASSERT (PciExBarBase <= MAX_UINT32 - SIZE_256MB);
      PciBase = (UINT32)(PciExBarBase + SIZE_256MB);
    } else {
      PciBase = (TopOfLowRam < BASE_2GB) ? BASE_2GB : TopOfLowRam;
    }

    //
    // address       purpose   size
    // ------------  --------  -------------------------
    // max(top, 2g)  PCI MMIO  0xFC000000 - max(top, 2g)
    // 0xFC000000    gap                           44 MB
    // 0xFEC00000    IO-APIC                        4 KB
    // 0xFEC01000    gap                         1020 KB
    // 0xFED00000    HPET                           1 KB
    // 0xFED00400    gap                          111 KB
    // 0xFED1C000    gap (PIIX4) / RCRB (ICH9)     16 KB
    // 0xFED20000    gap                          896 KB
    // 0xFEE00000    LAPIC                          1 MB
    //
    PciSize = 0xFC000000 - PciBase;
    AddIoMemoryBaseSizeHob (PciBase, PciSize);
    PcdStatus = PcdSet64S (PcdPciMmio32Base, PciBase);
    ASSERT_RETURN_ERROR (PcdStatus);
    PcdStatus = PcdSet64S (PcdPciMmio32Size, PciSize);
    ASSERT_RETURN_ERROR (PcdStatus);

    AddIoMemoryBaseSizeHob (0xFEC00000, SIZE_4KB);
    AddIoMemoryBaseSizeHob (0xFED00000, SIZE_1KB);
    if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) {
      AddIoMemoryBaseSizeHob (ICH9_ROOT_COMPLEX_BASE, SIZE_16KB);
      //
      // Note: there should be an
      //
      //   AddIoMemoryBaseSizeHob (PciExBarBase, SIZE_256MB);
      //
      // call below, just like the one above for RCBA. However, Linux insists
      // that the MMCONFIG area be marked in the E820 or UEFI memory map as
      // "reserved memory" -- Linux does not content itself with a simple gap
      // in the memory map wherever the MCFG ACPI table points to.
      //
      // This appears to be a safety measure. The PCI Firmware Specification
      // (rev 3.1) says in 4.1.2. "MCFG Table Description": "The resources can
      // *optionally* be returned in [...] EFIGetMemoryMap as reserved memory
      // [...]". (Emphasis added here.)
      //
      // Normally we add memory resource descriptor HOBs in
      // QemuInitializeRam(), and pre-allocate from those with memory
      // allocation HOBs in InitializeRamRegions(). However, the MMCONFIG area
      // is most definitely not RAM; so, as an exception, cover it with
      // uncacheable reserved memory right here.
      //
      AddReservedMemoryBaseSizeHob (PciExBarBase, SIZE_256MB, FALSE);
      BuildMemoryAllocationHob (PciExBarBase, SIZE_256MB,
        EfiReservedMemoryType);
    }
    AddIoMemoryBaseSizeHob (PcdGet32(PcdCpuLocalApicBaseAddress), SIZE_1MB);

    //
    // On Q35, the IO Port space is available for PCI resource allocations from
    // 0x6000 up.
    //
    if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) {
      PciIoBase = 0x6000;
      PciIoSize = 0xA000;
      ASSERT ((ICH9_PMBASE_VALUE & 0xF000) < PciIoBase);
    }
  }

  //
  // Add PCI IO Port space available for PCI resource allocations.
  //
  BuildResourceDescriptorHob (
    EFI_RESOURCE_IO,
    EFI_RESOURCE_ATTRIBUTE_PRESENT     |
    EFI_RESOURCE_ATTRIBUTE_INITIALIZED,
    PciIoBase,
    PciIoSize
    );
  PcdStatus = PcdSet64S (PcdPciIoBase, PciIoBase);
  ASSERT_RETURN_ERROR (PcdStatus);
  PcdStatus = PcdSet64S (PcdPciIoSize, PciIoSize);
  ASSERT_RETURN_ERROR (PcdStatus);
}

EFI_STATUS
GetNamedFwCfgBoolean (
  IN  CHAR8   *FwCfgFileName,
  OUT BOOLEAN *Setting
  )
{
  EFI_STATUS           Status;
  FIRMWARE_CONFIG_ITEM FwCfgItem;
  UINTN                FwCfgSize;
  UINT8                Value[3];

  Status = QemuFwCfgFindFile (FwCfgFileName, &FwCfgItem, &FwCfgSize);
  if (EFI_ERROR (Status)) {
    return Status;
  }
  if (FwCfgSize > sizeof Value) {
    return EFI_BAD_BUFFER_SIZE;
  }
  QemuFwCfgSelectItem (FwCfgItem);
  QemuFwCfgReadBytes (FwCfgSize, Value);

  if ((FwCfgSize == 1) ||
      (FwCfgSize == 2 && Value[1] == '\n') ||
      (FwCfgSize == 3 && Value[1] == '\r' && Value[2] == '\n')) {
    switch (Value[0]) {
      case '0':
      case 'n':
      case 'N':
        *Setting = FALSE;
        return EFI_SUCCESS;

      case '1':
      case 'y':
      case 'Y':
        *Setting = TRUE;
        return EFI_SUCCESS;

      default:
        break;
    }
  }
  return EFI_PROTOCOL_ERROR;
}

#define UPDATE_BOOLEAN_PCD_FROM_FW_CFG(TokenName)                   \
          do {                                                      \
            BOOLEAN       Setting;                                  \
            RETURN_STATUS PcdStatus;                                \
                                                                    \
            if (!EFI_ERROR (GetNamedFwCfgBoolean (                  \
                              "opt/ovmf/" #TokenName, &Setting))) { \
              PcdStatus = PcdSetBoolS (TokenName, Setting);         \
              ASSERT_RETURN_ERROR (PcdStatus);                      \
            }                                                       \
          } while (0)

VOID
NoexecDxeInitialization (
  VOID
  )
{
  UPDATE_BOOLEAN_PCD_FROM_FW_CFG (PcdPropertiesTableEnable);
  UPDATE_BOOLEAN_PCD_FROM_FW_CFG (PcdSetNxForStack);
}

VOID
PciExBarInitialization (
  VOID
  )
{
  union {
    UINT64 Uint64;
    UINT32 Uint32[2];
  } PciExBarBase;

  //
  // We only support the 256MB size for the MMCONFIG area:
  // 256 buses * 32 devices * 8 functions * 4096 bytes config space.
  //
  // The masks used below enforce the Q35 requirements that the MMCONFIG area
  // be (a) correctly aligned -- here at 256 MB --, (b) located under 64 GB.
  //
  // Note that (b) also ensures that the minimum address width we have
  // determined in AddressWidthInitialization(), i.e., 36 bits, will suffice
  // for DXE's page tables to cover the MMCONFIG area.
  //
  PciExBarBase.Uint64 = FixedPcdGet64 (PcdPciExpressBaseAddress);
  ASSERT ((PciExBarBase.Uint32[1] & MCH_PCIEXBAR_HIGHMASK) == 0);
  ASSERT ((PciExBarBase.Uint32[0] & MCH_PCIEXBAR_LOWMASK) == 0);

  //
  // Clear the PCIEXBAREN bit first, before programming the high register.
  //
  PciWrite32 (DRAMC_REGISTER_Q35 (MCH_PCIEXBAR_LOW), 0);

  //
  // Program the high register. Then program the low register, setting the
  // MMCONFIG area size and enabling decoding at once.
  //
  PciWrite32 (DRAMC_REGISTER_Q35 (MCH_PCIEXBAR_HIGH), PciExBarBase.Uint32[1]);
  PciWrite32 (
    DRAMC_REGISTER_Q35 (MCH_PCIEXBAR_LOW),
    PciExBarBase.Uint32[0] | MCH_PCIEXBAR_BUS_FF | MCH_PCIEXBAR_EN
    );
}

VOID
MiscInitialization (
  VOID
  )
{
  UINTN         PmCmd;
  UINTN         Pmba;
  UINT32        PmbaAndVal;
  UINT32        PmbaOrVal;
  UINTN         AcpiCtlReg;
  UINT8         AcpiEnBit;
  RETURN_STATUS PcdStatus;

  //
  // Disable A20 Mask
  //
  IoOr8 (0x92, BIT1);

  //
  // Build the CPU HOB with guest RAM size dependent address width and 16-bits
  // of IO space. (Side note: unlike other HOBs, the CPU HOB is needed during
  // S3 resume as well, so we build it unconditionally.)
  //
  BuildCpuHob (mPhysMemAddressWidth, 16);

  //
  // Determine platform type and save Host Bridge DID to PCD
  //
  switch (mHostBridgeDevId) {
    case INTEL_82441_DEVICE_ID:
      PmCmd      = POWER_MGMT_REGISTER_PIIX4 (PCI_COMMAND_OFFSET);
      Pmba       = POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMBA);
      PmbaAndVal = ~(UINT32)PIIX4_PMBA_MASK;
      PmbaOrVal  = PIIX4_PMBA_VALUE;
      AcpiCtlReg = POWER_MGMT_REGISTER_PIIX4 (PIIX4_PMREGMISC);
      AcpiEnBit  = PIIX4_PMREGMISC_PMIOSE;
      break;
    case INTEL_Q35_MCH_DEVICE_ID:
      PmCmd      = POWER_MGMT_REGISTER_Q35 (PCI_COMMAND_OFFSET);
      Pmba       = POWER_MGMT_REGISTER_Q35 (ICH9_PMBASE);
      PmbaAndVal = ~(UINT32)ICH9_PMBASE_MASK;
      PmbaOrVal  = ICH9_PMBASE_VALUE;
      AcpiCtlReg = POWER_MGMT_REGISTER_Q35 (ICH9_ACPI_CNTL);
      AcpiEnBit  = ICH9_ACPI_CNTL_ACPI_EN;
      break;
    default:
      DEBUG ((EFI_D_ERROR, "%a: Unknown Host Bridge Device ID: 0x%04x\n",
        __FUNCTION__, mHostBridgeDevId));
      ASSERT (FALSE);
      return;
  }
  PcdStatus = PcdSet16S (PcdOvmfHostBridgePciDevId, mHostBridgeDevId);
  ASSERT_RETURN_ERROR (PcdStatus);

  //
  // If the appropriate IOspace enable bit is set, assume the ACPI PMBA
  // has been configured (e.g., by Xen) and skip the setup here.
  // This matches the logic in AcpiTimerLibConstructor ().
  //
  if ((PciRead8 (AcpiCtlReg) & AcpiEnBit) == 0) {
    //
    // The PEI phase should be exited with fully accessibe ACPI PM IO space:
    // 1. set PMBA
    //
    PciAndThenOr32 (Pmba, PmbaAndVal, PmbaOrVal);

    //
    // 2. set PCICMD/IOSE
    //
    PciOr8 (PmCmd, EFI_PCI_COMMAND_IO_SPACE);

    //
    // 3. set ACPI PM IO enable bit (PMREGMISC:PMIOSE or ACPI_CNTL:ACPI_EN)
    //
    PciOr8 (AcpiCtlReg, AcpiEnBit);
  }

  if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) {
    //
    // Set Root Complex Register Block BAR
    //
    PciWrite32 (
      POWER_MGMT_REGISTER_Q35 (ICH9_RCBA),
      ICH9_ROOT_COMPLEX_BASE | ICH9_RCBA_EN
      );

    //
    // Set PCI Express Register Range Base Address
    //
    PciExBarInitialization ();
  }
}


VOID
BootModeInitialization (
  VOID
  )
{
  EFI_STATUS    Status;

  if (CmosRead8 (0xF) == 0xFE) {
    mBootMode = BOOT_ON_S3_RESUME;
  }
  CmosWrite8 (0xF, 0x00);

  Status = PeiServicesSetBootMode (mBootMode);
  ASSERT_EFI_ERROR (Status);

  Status = PeiServicesInstallPpi (mPpiBootMode);
  ASSERT_EFI_ERROR (Status);
}


VOID
ReserveEmuVariableNvStore (
  )
{
  EFI_PHYSICAL_ADDRESS VariableStore;
  RETURN_STATUS        PcdStatus;

  //
  // Allocate storage for NV variables early on so it will be
  // at a consistent address.  Since VM memory is preserved
  // across reboots, this allows the NV variable storage to survive
  // a VM reboot.
  //
  VariableStore =
    (EFI_PHYSICAL_ADDRESS)(UINTN)
      AllocateRuntimePages (
        EFI_SIZE_TO_PAGES (2 * PcdGet32 (PcdFlashNvStorageFtwSpareSize))
        );
  DEBUG ((EFI_D_INFO,
          "Reserved variable store memory: 0x%lX; size: %dkb\n",
          VariableStore,
          (2 * PcdGet32 (PcdFlashNvStorageFtwSpareSize)) / 1024
        ));
  PcdStatus = PcdSet64S (PcdEmuVariableNvStoreReserved, VariableStore);
  ASSERT_RETURN_ERROR (PcdStatus);
}


VOID
DebugDumpCmos (
  VOID
  )
{
  UINT32 Loop;

  DEBUG ((EFI_D_INFO, "CMOS:\n"));

  for (Loop = 0; Loop < 0x80; Loop++) {
    if ((Loop % 0x10) == 0) {
      DEBUG ((EFI_D_INFO, "%02x:", Loop));
    }
    DEBUG ((EFI_D_INFO, " %02x", CmosRead8 (Loop)));
    if ((Loop % 0x10) == 0xf) {
      DEBUG ((EFI_D_INFO, "\n"));
    }
  }
}


VOID
S3Verification (
  VOID
  )
{
#if defined (MDE_CPU_X64)
  if (FeaturePcdGet (PcdSmmSmramRequire) && mS3Supported) {
    DEBUG ((EFI_D_ERROR,
      "%a: S3Resume2Pei doesn't support X64 PEI + SMM yet.\n", __FUNCTION__));
    DEBUG ((EFI_D_ERROR,
      "%a: Please disable S3 on the QEMU command line (see the README),\n",
      __FUNCTION__));
    DEBUG ((EFI_D_ERROR,
      "%a: or build OVMF with \"OvmfPkgIa32X64.dsc\".\n", __FUNCTION__));
    ASSERT (FALSE);
    CpuDeadLoop ();
  }
#endif
}


/**
  Fetch the number of boot CPUs from QEMU and expose it to UefiCpuPkg modules.
  Set the mMaxCpuCount variable.
**/
VOID
MaxCpuCountInitialization (
  VOID
  )
{
  UINT16        ProcessorCount;
  RETURN_STATUS PcdStatus;

  QemuFwCfgSelectItem (QemuFwCfgItemSmpCpuCount);
  ProcessorCount = QemuFwCfgRead16 ();
  //
  // If the fw_cfg key or fw_cfg entirely is unavailable, load mMaxCpuCount
  // from the PCD default. No change to PCDs.
  //
  if (ProcessorCount == 0) {
    mMaxCpuCount = PcdGet32 (PcdCpuMaxLogicalProcessorNumber);
    return;
  }
  //
  // Otherwise, set mMaxCpuCount to the value reported by QEMU.
  //
  mMaxCpuCount = ProcessorCount;
  //
  // Additionally, tell UefiCpuPkg modules (a) the exact number of VCPUs, (b)
  // to wait, in the initial AP bringup, exactly as long as it takes for all of
  // the APs to report in. For this, we set the longest representable timeout
  // (approx. 71 minutes).
  //
  PcdStatus = PcdSet32S (PcdCpuMaxLogicalProcessorNumber, ProcessorCount);
  ASSERT_RETURN_ERROR (PcdStatus);
  PcdStatus = PcdSet32S (PcdCpuApInitTimeOutInMicroSeconds, MAX_UINT32);
  ASSERT_RETURN_ERROR (PcdStatus);
  DEBUG ((DEBUG_INFO, "%a: QEMU reports %d processor(s)\n", __FUNCTION__,
    ProcessorCount));
}


/**
  Perform Platform PEI initialization.

  @param  FileHandle      Handle of the file being invoked.
  @param  PeiServices     Describes the list of possible PEI Services.

  @return EFI_SUCCESS     The PEIM initialized successfully.

**/
EFI_STATUS
EFIAPI
InitializePlatform (
  IN       EFI_PEI_FILE_HANDLE  FileHandle,
  IN CONST EFI_PEI_SERVICES     **PeiServices
  )
{
  EFI_STATUS    Status;

  DEBUG ((DEBUG_INFO, "Platform PEIM Loaded\n"));

  DebugDumpCmos ();

  XenDetect ();

  if (QemuFwCfgS3Enabled ()) {
    DEBUG ((EFI_D_INFO, "S3 support was detected on QEMU\n"));
    mS3Supported = TRUE;
    Status = PcdSetBoolS (PcdAcpiS3Enable, TRUE);
    ASSERT_EFI_ERROR (Status);
  }

  S3Verification ();
  BootModeInitialization ();
  AddressWidthInitialization ();
  MaxCpuCountInitialization ();

  //
  // Query Host Bridge DID
  //
  mHostBridgeDevId = PciRead16 (OVMF_HOSTBRIDGE_DID);

  if (FeaturePcdGet (PcdSmmSmramRequire)) {
    Q35TsegMbytesInitialization ();
  }

  PublishPeiMemory ();

  InitializeRamRegions ();

  if (mXen) {
    DEBUG ((EFI_D_INFO, "Xen was detected\n"));
    InitializeXen ();
  }

  if (mBootMode != BOOT_ON_S3_RESUME) {
    if (!FeaturePcdGet (PcdSmmSmramRequire)) {
      ReserveEmuVariableNvStore ();
    }
    PeiFvInitialization ();
    MemMapInitialization ();
    NoexecDxeInitialization ();
  }

  AmdSevInitialize ();
  MiscInitialization ();
  InstallFeatureControlCallback ();

  return EFI_SUCCESS;
}