/** @file
  DXE Library for VTD ACPI table initialization.

  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Library/DxeVtdInitLib.h>
#include <Library/DxeVtdPolicyLib.h>
#include <Library/VtdInitFruLib.h>
#include <Register/SaRegsHostBridge.h>

///
/// Global Variables
///
GLOBAL_REMOVE_IF_UNREFERENCED VTD_DATA_HOB     *mVtdDataHob;

BOOLEAN mInterruptRemappingSupport;

/**
  Get the corresponding device Enable/Disable bit according DevNum and FunNum

  @param[in] DevNum  - Device Number
  @param[in] FunNum  - Function Number

  @retval If the device is found, return disable/Enable bit in FD/Deven reigster
  @retval If not found return 0xFF
**/
UINT16
GetFunDisableBit (
  UINT8 DevNum,
  UINT8 FunNum
  )
{
  UINTN Index;

  for (Index = 0; Index < mDevEnMapSize; Index++) {
    if (mDevEnMap[Index][0] == ((DevNum << 0x08) | FunNum)) {
      return mDevEnMap[Index][1];
    }
  }

  return 0xFF;
}

/**
  Update the DRHD structure

  @param[in, out] DrhdEnginePtr       - A pointer to DRHD structure
**/
VOID
UpdateDrhd (
  IN OUT VOID *DrhdEnginePtr
  )
{
  UINT16                        Length;
  UINT16                        DisableBit;
  BOOLEAN                       NeedRemove;
  EFI_ACPI_DRHD_ENGINE1_STRUCT  *DrhdEngine;

  //
  // Convert DrhdEnginePtr to EFI_ACPI_DRHD_ENGINE1_STRUCT Pointer
  //
  DrhdEngine      = (EFI_ACPI_DRHD_ENGINE1_STRUCT *) DrhdEnginePtr;
  Length          = DrhdEngine->DrhdHeader.Header.Length;
  DisableBit = GetFunDisableBit (
                 DrhdEngine->DeviceScope[0].PciPath.Device,
                 DrhdEngine->DeviceScope[0].PciPath.Function
                 );
  NeedRemove = FALSE;

  if ((DisableBit == 0xFF) ||
      (DrhdEngine->DrhdHeader.RegisterBaseAddress == 0) ||
      ((DisableBit == 0x80) &&
       (PciSegmentRead32 (PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, 0, DrhdEngine->DeviceScope[0].PciPath.Device, DrhdEngine->DeviceScope[0].PciPath.Function, 0x00)) == 0xFFFFFFFF))
      ) {
    NeedRemove = TRUE;
  }
  if ((DrhdEngine->DeviceScope[0].PciPath.Device == IGD_DEV_NUM) && (DrhdEngine->DeviceScope[0].PciPath.Function == IGD_FUN_NUM) &&
      (PciSegmentRead32 (PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, 0, DrhdEngine->DeviceScope[0].PciPath.Device, DrhdEngine->DeviceScope[0].PciPath.Function, 0x00)) != 0xFFFFFFFF)) {
    NeedRemove = FALSE;
  }
  if (NeedRemove) {
    Length -= sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE);
  }
  ///
  /// If no devicescope is left, we set the structure length as 0x00
  ///
  if ((Length > EFI_ACPI_DRHD_ENGINE_HEADER_LENGTH) || (DrhdEngine->DrhdHeader.Flags == 0x01)) {
    DrhdEngine->DrhdHeader.Header.Length = Length;
  } else {
    DrhdEngine->DrhdHeader.Header.Length = 0;
  }
}

/**
  Get IOAPIC ID from LPC

  @retval APIC ID
**/
UINT8
GetIoApicId (
  VOID
  )
{
  UINT32                IoApicAddress;
  UINT32                IoApicId;

  IoApicAddress = PcdGet32 (PcdSiIoApicBaseAddress);
  ///
  /// Get current IO APIC ID
  ///
  MmioWrite8 ((UINTN) (IoApicAddress + R_IO_APIC_MEM_INDEX_OFFSET), 0);
  IoApicId = MmioRead32 ((UINTN) (IoApicAddress + R_IO_APIC_MEM_DATA_OFFSET)) >> 24;

  return (UINT8) IoApicId;
}

/**
  Update the second DRHD structure

  @param[in, out] DrhdEnginePtr       - A pointer to DRHD structure
**/
VOID
UpdateDrhd2 (
  IN OUT VOID *DrhdEnginePtr
  )
{
  UINT16                        Length;
  UINTN                         DeviceScopeNum;
  UINTN                         ValidDeviceScopeNum;
  UINT16                        Index;
  UINT8                         Bus;
  UINT8                         Path[2];
  BOOLEAN                       NeedRemove;
  EFI_ACPI_DRHD_ENGINE3_STRUCT  *DrhdEngine;
  VOID                          *HobPtr;
  PCH_INFO_HOB                  *PchInfoHob;

  ///
  /// Convert DrhdEnginePtr to EFI_ACPI_DRHD_ENGINE3_STRUCT Pointer
  ///
  DrhdEngine      = (EFI_ACPI_DRHD_ENGINE3_STRUCT *) DrhdEnginePtr;

  Length          = DrhdEngine->DrhdHeader.Header.Length;
  DeviceScopeNum  = (DrhdEngine->DrhdHeader.Header.Length - EFI_ACPI_DRHD_ENGINE_HEADER_LENGTH) / sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE);
  Bus             = 0;
  ValidDeviceScopeNum = 0;
  Path[0]         = 0;
  Path[1]         = 0;

  HobPtr = GetFirstGuidHob (&gPchInfoHobGuid);
  ASSERT (HobPtr != NULL);
  if (HobPtr == NULL) {
    return;
  }
  PchInfoHob = (PCH_INFO_HOB *) GET_GUID_HOB_DATA (HobPtr);
  ASSERT (PchInfoHob != NULL);
  if (PchInfoHob == NULL) {
    return;
  }

  for (Index = 0; Index < DeviceScopeNum; Index++) {
    NeedRemove = FALSE;
    /**
      For HPET and APIC, update device scope if Interrupt remapping is supported. remove device scope
      if interrupt remapping is not supported.
      - Index = 0 - IOAPIC
      - Index = 1 - HPET
    **/
    if (mInterruptRemappingSupport) {
      if (Index == 0) {
        ///
        /// Update source id for IoApic's device scope entry
        ///
        Bus = (UINT8) PchInfoHob->IoApicBusNum;
        Path[0] = (UINT8) PchInfoHob->IoApicDevNum;
        Path[1] = (UINT8) PchInfoHob->IoApicFuncNum;
        DrhdEngine->DeviceScope[Index].DeviceScopeStructureHeader.StartBusNumber = Bus;
        DrhdEngine->DeviceScope[Index].PciPath.Device = Path[0];
        DrhdEngine->DeviceScope[Index].PciPath.Function = Path[1];
        //
        // Update APIC ID
        //
        DrhdEngine->DeviceScope[Index].DeviceScopeStructureHeader.EnumerationId = GetIoApicId ();
      }
      if (Index == 1) {
        ///
        /// Update source id for HPET's device scope entry
        ///
        Bus     = (UINT8) PchInfoHob->HpetBusNum;
        Path[0] = (UINT8) PchInfoHob->HpetDevNum;
        Path[1] = (UINT8) PchInfoHob->HpetFuncNum;
        DrhdEngine->DeviceScope[Index].DeviceScopeStructureHeader.StartBusNumber = Bus;
        DrhdEngine->DeviceScope[Index].PciPath.Device = Path[0];
        DrhdEngine->DeviceScope[Index].PciPath.Function = Path[1];
      }
    } else {
      if ((Index == 0) || (Index == 1)) {
        NeedRemove = TRUE;
      }
    }

    CopyMem (
      &DrhdEngine->DeviceScope[ValidDeviceScopeNum],
      &DrhdEngine->DeviceScope[Index],
      sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE)
      );
    if (NeedRemove) {
      Length -= sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE);
    } else {
      ValidDeviceScopeNum++;
    }
  }
  ///
  /// If no devicescope is left, we set the structure length as 0x00
  ///
  if ((Length > EFI_ACPI_DRHD_ENGINE_HEADER_LENGTH) || (DrhdEngine->DrhdHeader.Flags == 0x01)) {
    DrhdEngine->DrhdHeader.Header.Length = Length;
  } else {
    DrhdEngine->DrhdHeader.Header.Length = 0;
  }
}

/**
  Update the RMRR structure

  @param[in, out] RmrrPtr             - A pointer to RMRR structure
**/
VOID
UpdateRmrr (
  IN OUT VOID *RmrrPtr
  )
{
  UINT16                  Length;
  UINT16                  DisableBit;
  UINTN                   DeviceScopeNum;
  UINTN                   ValidDeviceScopeNum;
  UINTN                   Index;
  BOOLEAN                 NeedRemove;
  EFI_ACPI_RMRR_USB_STRUC *Rmrr;

  ///
  /// To make sure all devicescope can be checked,
  /// we convert the RmrrPtr to EFI_ACPI_RMRR_USB_STRUC pointer
  ///
  Rmrr                = (EFI_ACPI_RMRR_USB_STRUC *) RmrrPtr;

  Length              = Rmrr->RmrrHeader.Header.Length;
  ValidDeviceScopeNum = 0;
  DeviceScopeNum      = (Rmrr->RmrrHeader.Header.Length - EFI_ACPI_RMRR_HEADER_LENGTH) / sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE);
  for (Index = 0; Index < DeviceScopeNum; Index++) {
    DisableBit = GetFunDisableBit (
                   Rmrr->DeviceScope[Index].PciPath.Device,
                   Rmrr->DeviceScope[Index].PciPath.Function
                   );
    NeedRemove = FALSE;
    if ((DisableBit == 0xFF) ||
        ((DisableBit == 0x80) &&
         (PciSegmentRead32 (PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, 0, Rmrr->DeviceScope[Index].PciPath.Device, Rmrr->DeviceScope[Index].PciPath.Function, 0x00)) == 0xFFFFFFFF))
        ) {
      NeedRemove = TRUE;
    } else if (DisableBit == 0x8F) {
      DEBUG ((DEBUG_ERROR, "Rmrr->RmrrHeader.ReservedMemoryRegionBaseAddress %x\n", Rmrr->RmrrHeader.ReservedMemoryRegionBaseAddress));

      if (Rmrr->RmrrHeader.ReservedMemoryRegionBaseAddress != 0) {
        DEBUG ((DEBUG_ERROR, "NeedRemove = FALSE\n"));
        NeedRemove = FALSE;
      } else {
        DEBUG ((DEBUG_ERROR, "NeedRemove = TRUE\n"));
        NeedRemove = TRUE;
      }
    }
    CopyMem (
      &Rmrr->DeviceScope[ValidDeviceScopeNum],
      &Rmrr->DeviceScope[Index],
      sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE)
      );

    if (Rmrr->RmrrHeader.ReservedMemoryRegionLimitAddress == 0x0) {
      NeedRemove = TRUE;
    }

    if (NeedRemove) {
      Length -= sizeof (EFI_ACPI_DEV_SCOPE_STRUCTURE);
    } else {
      ValidDeviceScopeNum++;
    }
  }
  ///
  /// If No deviceScope is left, set length as 0x00
  ///
  if (Length > EFI_ACPI_RMRR_HEADER_LENGTH) {
    Rmrr->RmrrHeader.Header.Length = Length;
  } else {
    Rmrr->RmrrHeader.Header.Length = 0;
  }
}

/**
  Update the DMAR table

  @param[in, out] TableHeader         - The table to be set
  @param[in, out] Version             - Version to publish
**/
VOID
DmarTableUpdate (
  IN OUT   EFI_ACPI_DESCRIPTION_HEADER       *TableHeader,
  IN OUT   EFI_ACPI_TABLE_VERSION            *Version
  )
{
  EFI_ACPI_DMAR_TABLE *DmarTable;
  EFI_ACPI_DMAR_TABLE TempDmarTable;
  UINTN               Offset;
  UINTN               StructureLen;
  UINT64              McD0BaseAddress;
  UINT16              IgdMode;
  UINT16              GttMode;
  UINT32              IgdMemSize;
  UINT32              GttMemSize;
  EFI_STATUS          Status;
  VTD_DXE_CONFIG      *VtdDxeConfig;
  SA_POLICY_PROTOCOL  *SaPolicy;


  IgdMemSize  = 0;
  GttMemSize  = 0;
  DmarTable   = (EFI_ACPI_DMAR_TABLE *) TableHeader;

  Status = gBS->LocateProtocol (&gSaPolicyProtocolGuid, NULL, (VOID **) &SaPolicy);
  ASSERT_EFI_ERROR (Status);

  Status = GetConfigBlock ((VOID *) SaPolicy, &gVtdDxeConfigGuid, (VOID *)&VtdDxeConfig);
  ASSERT_EFI_ERROR (Status);

  ///
  /// Set INTR_REMAP bit (BIT 0) if interrupt remapping is supported
  ///
  if (mInterruptRemappingSupport) {
    DmarTable->DmarHeader.Flags |= BIT0;
  }

  if (mVtdDataHob->X2ApicOptOut == 1) {
    DmarTable->DmarHeader.Flags |= BIT1;
  } else {
    DmarTable->DmarHeader.Flags &= 0xFD;
  }

  ///
  /// Set DMA_CONTROL_GUARANTEE bit (BIT 2) if Dma Control Guarantee is supported
  ///
  if (mVtdDataHob->DmaControlGuarantee == 1) {
    DmarTable->DmarHeader.Flags |= BIT2;
  }
  ///
  /// Get OemId
  ///
  CopyMem (DmarTable->DmarHeader.Header.OemId, PcdGetPtr (PcdAcpiDefaultOemId), sizeof (DmarTable->DmarHeader.Header.OemId));
  DmarTable->DmarHeader.Header.OemTableId      = PcdGet64 (PcdAcpiDefaultOemTableId);
  DmarTable->DmarHeader.Header.OemRevision     = PcdGet32 (PcdAcpiDefaultOemRevision);
  DmarTable->DmarHeader.Header.CreatorId       = PcdGet32 (PcdAcpiDefaultCreatorId);
  DmarTable->DmarHeader.Header.CreatorRevision = PcdGet32 (PcdAcpiDefaultCreatorRevision);

  ///
  /// Calculate IGD memsize
  ///
  McD0BaseAddress = PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, SA_MC_BUS, 0, 0, 0);
  IgdMode = ((PciSegmentRead16 (McD0BaseAddress + R_SA_GGC) & B_SA_GGC_GMS_MASK) >> N_SA_GGC_GMS_OFFSET) & 0xFF;
  if (IgdMode < 0xF0) {
    IgdMemSize = IgdMode * 32 * (1024) * (1024);
  } else {
    IgdMemSize = 4 * (IgdMode - 0xF0 + 1) * (1024) * (1024);
  }
  ///
  /// Calculate GTT mem size
  ///
  GttMemSize = 0;
  GttMode = (PciSegmentRead16 (McD0BaseAddress + R_SA_GGC) & B_SA_GGC_GGMS_MASK) >> N_SA_GGC_GGMS_OFFSET;
  if (GttMode <= V_SA_GGC_GGMS_8MB) {
    GttMemSize = (1 << GttMode) * (1024) * (1024);
  }

  DmarTable->RmrrIgd.RmrrHeader.ReservedMemoryRegionBaseAddress   = (PciSegmentRead32 (McD0BaseAddress + R_SA_BGSM) & ~(0x01));
  DmarTable->RmrrIgd.RmrrHeader.ReservedMemoryRegionLimitAddress  = DmarTable->RmrrIgd.RmrrHeader.ReservedMemoryRegionBaseAddress + IgdMemSize + GttMemSize - 1;
  DEBUG ((DEBUG_INFO, "RMRR Base  address IGD %016lX\n", DmarTable->RmrrIgd.RmrrHeader.ReservedMemoryRegionBaseAddress));
  DEBUG ((DEBUG_INFO, "RMRR Limit address IGD %016lX\n", DmarTable->RmrrIgd.RmrrHeader.ReservedMemoryRegionLimitAddress));

  ///
  /// Update DRHD structures of DmarTable
  ///
  DmarTable->DrhdEngine1.DrhdHeader.RegisterBaseAddress = ReadVtdBaseAddress(0);
  DmarTable->DrhdEngine3.DrhdHeader.RegisterBaseAddress = ReadVtdBaseAddress (2);

  DEBUG ((DEBUG_INFO, "VTD base address 1 = %x\n", DmarTable->DrhdEngine1.DrhdHeader.RegisterBaseAddress));
  DEBUG ((DEBUG_INFO, "VTD base address 3 = %x\n", DmarTable->DrhdEngine3.DrhdHeader.RegisterBaseAddress));
  ///
  /// copy DmarTable to TempDmarTable to be processed
  ///
  CopyMem (&TempDmarTable, DmarTable, sizeof (EFI_ACPI_DMAR_TABLE));

  ///
  /// Update DRHD structures of temp DMAR table
  ///
  UpdateDrhd (&TempDmarTable.DrhdEngine1);
  UpdateDrhd2 (&TempDmarTable.DrhdEngine3);

  ///
  /// Remove unused device scope or entire DRHD structures
  ///
  Offset = (UINTN) (&TempDmarTable.DrhdEngine1);
  if (TempDmarTable.DrhdEngine1.DrhdHeader.Header.Length != 0) {
    Offset += TempDmarTable.DrhdEngine1.DrhdHeader.Header.Length;
  }
  if (TempDmarTable.DrhdEngine3.DrhdHeader.Header.Length != 0) {
    StructureLen = TempDmarTable.DrhdEngine3.DrhdHeader.Header.Length;
    CopyMem ((VOID *) Offset, (VOID *) &TempDmarTable.DrhdEngine3, TempDmarTable.DrhdEngine3.DrhdHeader.Header.Length);
    Offset += StructureLen;
  }
  ///
  /// Remove unused device scope or entire RMRR structures
  ///
  if (TempDmarTable.RmrrIgd.RmrrHeader.Header.Length != 0) {
    StructureLen = TempDmarTable.RmrrIgd.RmrrHeader.Header.Length;
    CopyMem ((VOID *) Offset, (VOID *) &TempDmarTable.RmrrIgd, TempDmarTable.RmrrIgd.RmrrHeader.Header.Length);
    Offset += StructureLen;
  }
  Offset = Offset - (UINTN) &TempDmarTable;
  ///
  /// Re-calculate DMAR table check sum
  ///
  TempDmarTable.DmarHeader.Header.Checksum = (UINT8) (TempDmarTable.DmarHeader.Header.Checksum + TempDmarTable.DmarHeader.Header.Length - Offset);
  ///
  /// Set DMAR table length
  ///
  TempDmarTable.DmarHeader.Header.Length = (UINT32) Offset;
  ///
  /// Replace DMAR table with rebuilt table TempDmarTable
  ///
  CopyMem ((VOID *) DmarTable, (VOID *) &TempDmarTable, TempDmarTable.DmarHeader.Header.Length);
}

/**
  EndOfPcieEnumration routine for update DMAR
**/
VOID
UpdateDmarEndOfPcieEnum (
  VOID
  )
{
  EFI_STATUS                      Status;
  EFI_HANDLE                      *HandleBuffer;
  UINTN                           NumberOfHandles;
  EFI_FV_FILETYPE                 FileType;
  UINT32                          FvStatus;
  EFI_FV_FILE_ATTRIBUTES          Attributes;
  UINTN                           Size;
  UINTN                           i;
  INTN                            Instance;
  EFI_ACPI_TABLE_VERSION          Version;
  EFI_ACPI_COMMON_HEADER          *CurrentTable;
  UINTN                           AcpiTableHandle;
  EFI_FIRMWARE_VOLUME2_PROTOCOL   *FwVol;
  EFI_ACPI_TABLE_PROTOCOL         *AcpiTable;
  EFI_ACPI_DESCRIPTION_HEADER     *VtdAcpiTable;
  STATIC BOOLEAN                  Triggered = FALSE;


  if (Triggered) {
    return;
  }

  Triggered     = TRUE;

  FwVol         = NULL;
  AcpiTable     = NULL;
  VtdAcpiTable  = NULL;

  DEBUG ((DEBUG_INFO, "UpdateDmarEndOfPcieEnum \n"));


  ///
  /// Fix DMAR Table always created, skip install when disabled
  ///
  if ((mVtdDataHob->VtdDisable == TRUE) || (PciSegmentRead32 (PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, SA_MC_BUS, 0, 0, R_SA_MC_CAPID0_A_OFFSET)) & BIT23)) {
    DEBUG ((DEBUG_INFO, "Vtd Disabled, skip DMAR Table install\n"));
    return;
  }


  ///
  /// Locate ACPI support protocol
  ///
  Status = gBS->LocateProtocol (&gEfiAcpiTableProtocolGuid, NULL, (VOID **) &AcpiTable);

  ///
  /// Locate protocol.
  /// There is little chance we can't find an FV protocol
  ///
  Status = gBS->LocateHandleBuffer (
                  ByProtocol,
                  &gEfiFirmwareVolume2ProtocolGuid,
                  NULL,
                  &NumberOfHandles,
                  &HandleBuffer
                  );
  ASSERT_EFI_ERROR (Status);

  ///
  /// Looking for FV with ACPI storage file
  ///
  for (i = 0; i < NumberOfHandles; i++) {
    ///
    /// Get the protocol on this handle
    /// This should not fail because of LocateHandleBuffer
    ///
    Status = gBS->HandleProtocol (
                    HandleBuffer[i],
                    &gEfiFirmwareVolume2ProtocolGuid,
                    (VOID **) &FwVol
                    );
    ASSERT_EFI_ERROR (Status);

    ///
    /// See if it has the ACPI storage file
    ///
    Size      = 0;
    FvStatus  = 0;
    Status = FwVol->ReadFile (
                      FwVol,
                      &gSaAcpiTableStorageGuid,
                      NULL,
                      &Size,
                      &FileType,
                      &Attributes,
                      &FvStatus
                      );

    ///
    /// If we found it, then we are done
    ///
    if (Status == EFI_SUCCESS) {
      break;
    }
  }
  ///
  /// Our exit status is determined by the success of the previous operations
  /// If the protocol was found, Instance already points to it.
  ///
  ///
  /// Free any allocated buffers
  ///
  FreePool (HandleBuffer);

  ///
  /// Sanity check that we found our data file
  ///
  ASSERT (FwVol);
  if (FwVol == NULL) {
    return;
  }
  ///
  /// By default, a table belongs in all ACPI table versions published.
  ///
  Version = EFI_ACPI_TABLE_VERSION_1_0B | EFI_ACPI_TABLE_VERSION_2_0 | EFI_ACPI_TABLE_VERSION_3_0;

  ///
  /// Read tables from the storage file.
  ///
  Instance      = 0;
  CurrentTable  = NULL;

  while (Status == EFI_SUCCESS) {
    Status = FwVol->ReadSection (
                      FwVol,
                      &gSaAcpiTableStorageGuid,
                      EFI_SECTION_RAW,
                      Instance,
                      (VOID **) &CurrentTable,
                      &Size,
                      &FvStatus
                      );

    if (!EFI_ERROR (Status)) {
      ///
      /// Check the Signature ID to modify the table
      ///
      if ((CurrentTable != NULL) && ((EFI_ACPI_DESCRIPTION_HEADER *) CurrentTable)->Signature == EFI_ACPI_VTD_DMAR_TABLE_SIGNATURE) {
        VtdAcpiTable = (EFI_ACPI_DESCRIPTION_HEADER *) CurrentTable;
        DmarTableUpdate (VtdAcpiTable, &Version);
        break;
      }
      ///
      /// Increment the instance
      ///
      Instance++;
      if (CurrentTable != NULL) {
        gBS->FreePool (CurrentTable);
        CurrentTable = NULL;
      }
    }
  }
  ///
  /// Update the VTD table in the ACPI tables.
  ///
  AcpiTableHandle = 0;
  if (VtdAcpiTable != NULL) {
    Status = AcpiTable->InstallAcpiTable (
                          AcpiTable,
                          VtdAcpiTable,
                          VtdAcpiTable->Length,
                          &AcpiTableHandle
                          );
    FreePool (VtdAcpiTable);
  }
}

/**
  Locate the VT-d ACPI tables data file and read ACPI SSDT tables.
  Publish the appropriate SSDT based on current configuration and capabilities.

  @param[in] SaPolicy     -  SA DXE Policy protocol

  @retval EFI_SUCCESS     - Vtd initialization complete
  @exception EFI_UNSUPPORTED - Vtd is not enabled by policy
**/
EFI_STATUS
VtdInit (
  IN  SA_POLICY_PROTOCOL    *SaPolicy
  )
{
  EFI_STATUS                      Status;
  UINT64                          McD0BaseAddress;
  UINT64                          McD2BaseAddress;
  SYSTEM_AGENT_NVS_AREA_PROTOCOL  *SaNvsAreaProtocol;
  UINT8                           Index;

  mInterruptRemappingSupport  = FALSE;
  mVtdDataHob = NULL;
  mVtdDataHob = GetFirstGuidHob(&gVtdDataHobGuid);
  if (mVtdDataHob != NULL) {
    mInterruptRemappingSupport = mVtdDataHob->InterruptRemappingSupport;
  }

  ///
  ///  Locate the SA Global NVS Protocol.
  ///
  Status = gBS->LocateProtocol (
                  &gSaNvsAreaProtocolGuid,
                  NULL,
                  (VOID **) &SaNvsAreaProtocol
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  McD0BaseAddress  = PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, SA_MC_BUS, 0, 0, 0);
  McD2BaseAddress  = PCI_SEGMENT_LIB_ADDRESS (SA_SEG_NUM, IGD_BUS_NUM, IGD_DEV_NUM, IGD_FUN_NUM, 0);

  if (mVtdDataHob != NULL) {
    SaNvsAreaProtocol->Area->VtdDisable = mVtdDataHob->VtdDisable;
  }

  for (Index = 0; Index < VTD_ENGINE_NUMBER; Index++) {
    SaNvsAreaProtocol->Area->VtdBaseAddress[Index] = ReadVtdBaseAddress (Index);
  }
  SaNvsAreaProtocol->Area->VtdEngine1Vid = PciSegmentRead16(McD2BaseAddress + PCI_VENDOR_ID_OFFSET);

  if (mVtdDataHob != NULL) {
    if ((mVtdDataHob->VtdDisable) || (PciSegmentRead32 (McD0BaseAddress + R_SA_MC_CAPID0_A_OFFSET) & BIT23)) {
      DEBUG ((DEBUG_WARN, "VTd disabled or no capability!\n"));
      return EFI_UNSUPPORTED;
    }
  }
  ///
  /// Check SA supports VTD and VTD is enabled in setup menu
  ///
  DEBUG ((DEBUG_INFO, "VTd enabled\n"));

  return EFI_SUCCESS;
}