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/** @file

  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
  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.

**/

#include <Uefi.h>
#include <PiPei.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/HobLib.h>
#include <IndustryStandard/Vtd.h>
#include <Ppi/VtdInfo.h>

#include "IntelVTdPmrPei.h"

/**
  Dump DMAR DeviceScopeEntry.

  @param[in]  DmarDeviceScopeEntry  DMAR DeviceScopeEntry
**/
VOID
DumpDmarDeviceScopeEntry (
  IN EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER     *DmarDeviceScopeEntry
  )
{
  UINTN   PciPathNumber;
  UINTN   PciPathIndex;
  EFI_ACPI_DMAR_PCI_PATH  *PciPath;

  if (DmarDeviceScopeEntry == NULL) {
    return;
  }

  DEBUG ((DEBUG_INFO,
    "    *************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    "    *       DMA-Remapping Device Scope Entry Structure                      *\n"
    ));
  DEBUG ((DEBUG_INFO,
    "    *************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    (sizeof(UINTN) == sizeof(UINT64)) ?
    "    DMAR Device Scope Entry address ...................... 0x%016lx\n" :
    "    DMAR Device Scope Entry address ...................... 0x%08x\n",
    DmarDeviceScopeEntry
    ));
  DEBUG ((DEBUG_INFO,
    "      Device Scope Entry Type ............................ 0x%02x\n",
    DmarDeviceScopeEntry->Type
    ));
  switch (DmarDeviceScopeEntry->Type) {
  case EFI_ACPI_DEVICE_SCOPE_ENTRY_TYPE_PCI_ENDPOINT:
    DEBUG ((DEBUG_INFO,
      "        PCI Endpoint Device\n"
      ));
    break;
  case EFI_ACPI_DEVICE_SCOPE_ENTRY_TYPE_PCI_BRIDGE:
    DEBUG ((DEBUG_INFO,
      "        PCI Sub-hierachy\n"
      ));
    break;
  default:
    break;
  }
  DEBUG ((DEBUG_INFO,
    "      Length ............................................. 0x%02x\n",
    DmarDeviceScopeEntry->Length
    ));
  DEBUG ((DEBUG_INFO,
    "      Enumeration ID ..................................... 0x%02x\n",
    DmarDeviceScopeEntry->EnumerationId
    ));
  DEBUG ((DEBUG_INFO,
    "      Starting Bus Number ................................ 0x%02x\n",
    DmarDeviceScopeEntry->StartBusNumber
    ));

  PciPathNumber = (DmarDeviceScopeEntry->Length - sizeof(EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER)) / sizeof(EFI_ACPI_DMAR_PCI_PATH);
  PciPath = (EFI_ACPI_DMAR_PCI_PATH *)(DmarDeviceScopeEntry + 1);
  for (PciPathIndex = 0; PciPathIndex < PciPathNumber; PciPathIndex++) {
    DEBUG ((DEBUG_INFO,
      "      Device ............................................. 0x%02x\n",
      PciPath[PciPathIndex].Device
      ));
    DEBUG ((DEBUG_INFO,
      "      Function ........................................... 0x%02x\n",
      PciPath[PciPathIndex].Function
      ));
  }

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

  return;
}

/**
  Dump DMAR RMRR table.

  @param[in]  Rmrr  DMAR RMRR table
**/
VOID
DumpDmarRmrr (
  IN EFI_ACPI_DMAR_RMRR_HEADER *Rmrr
  )
{
  EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER       *DmarDeviceScopeEntry;
  INTN                                    RmrrLen;

  if (Rmrr == NULL) {
    return;
  }

  DEBUG ((DEBUG_INFO,
    "  ***************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    "  *       Reserved Memory Region Reporting Structure                        *\n"
    ));
  DEBUG ((DEBUG_INFO,
    "  ***************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    (sizeof(UINTN) == sizeof(UINT64)) ?
    "  RMRR address ........................................... 0x%016lx\n" :
    "  RMRR address ........................................... 0x%08x\n",
    Rmrr
    ));
  DEBUG ((DEBUG_INFO,
    "    Type ................................................. 0x%04x\n",
    Rmrr->Header.Type
    ));
  DEBUG ((DEBUG_INFO,
    "    Length ............................................... 0x%04x\n",
    Rmrr->Header.Length
    ));
  DEBUG ((DEBUG_INFO,
    "    Segment Number ....................................... 0x%04x\n",
    Rmrr->SegmentNumber
    ));
  DEBUG ((DEBUG_INFO,
    "    Reserved Memory Region Base Address .................. 0x%016lx\n",
    Rmrr->ReservedMemoryRegionBaseAddress
    ));
  DEBUG ((DEBUG_INFO,
    "    Reserved Memory Region Limit Address ................. 0x%016lx\n",
    Rmrr->ReservedMemoryRegionLimitAddress
    ));

  RmrrLen  = Rmrr->Header.Length - sizeof(EFI_ACPI_DMAR_RMRR_HEADER);
  DmarDeviceScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)(Rmrr + 1);
  while (RmrrLen > 0) {
    DumpDmarDeviceScopeEntry (DmarDeviceScopeEntry);
    RmrrLen -= DmarDeviceScopeEntry->Length;
    DmarDeviceScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)DmarDeviceScopeEntry + DmarDeviceScopeEntry->Length);
  }

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

  return;
}

/**
  Dump DMAR DRHD table.

  @param[in]  Drhd  DMAR DRHD table
**/
VOID
DumpDmarDrhd (
  IN EFI_ACPI_DMAR_DRHD_HEADER *Drhd
  )
{
  EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER       *DmarDeviceScopeEntry;
  INTN                                    DrhdLen;

  if (Drhd == NULL) {
    return;
  }

  DEBUG ((DEBUG_INFO,
    "  ***************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    "  *       DMA-Remapping Hardware Definition Structure                       *\n"
    ));
  DEBUG ((DEBUG_INFO,
    "  ***************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    (sizeof(UINTN) == sizeof(UINT64)) ?
    "  DRHD address ........................................... 0x%016lx\n" :
    "  DRHD address ........................................... 0x%08x\n",
    Drhd
    ));
  DEBUG ((DEBUG_INFO,
    "    Type ................................................. 0x%04x\n",
    Drhd->Header.Type
    ));
  DEBUG ((DEBUG_INFO,
    "    Length ............................................... 0x%04x\n",
    Drhd->Header.Length
    ));
  DEBUG ((DEBUG_INFO,
    "    Flags ................................................ 0x%02x\n",
    Drhd->Flags
    ));
  DEBUG ((DEBUG_INFO,
    "      INCLUDE_PCI_ALL .................................... 0x%02x\n",
    Drhd->Flags & EFI_ACPI_DMAR_DRHD_FLAGS_INCLUDE_PCI_ALL
    ));
  DEBUG ((DEBUG_INFO,
    "    Segment Number ....................................... 0x%04x\n",
    Drhd->SegmentNumber
    ));
  DEBUG ((DEBUG_INFO,
    "    Register Base Address ................................ 0x%016lx\n",
    Drhd->RegisterBaseAddress
    ));

  DrhdLen  = Drhd->Header.Length - sizeof(EFI_ACPI_DMAR_DRHD_HEADER);
  DmarDeviceScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)(Drhd + 1);
  while (DrhdLen > 0) {
    DumpDmarDeviceScopeEntry (DmarDeviceScopeEntry);
    DrhdLen -= DmarDeviceScopeEntry->Length;
    DmarDeviceScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)DmarDeviceScopeEntry + DmarDeviceScopeEntry->Length);
  }

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

  return;
}

/**
  Dump DMAR ACPI table.

  @param[in]  Dmar  DMAR ACPI table
**/
VOID
DumpAcpiDMAR (
  IN EFI_ACPI_DMAR_HEADER  *Dmar
  )
{
  EFI_ACPI_DMAR_STRUCTURE_HEADER *DmarHeader;
  INTN                  DmarLen;

  if (Dmar == NULL) {
    return;
  }

  //
  // Dump Dmar table
  //
  DEBUG ((DEBUG_INFO,
    "*****************************************************************************\n"
    ));
  DEBUG ((DEBUG_INFO,
    "*         DMAR Table                                                        *\n"
    ));
  DEBUG ((DEBUG_INFO,
    "*****************************************************************************\n"
    ));

  DEBUG ((DEBUG_INFO,
    (sizeof(UINTN) == sizeof(UINT64)) ?
    "DMAR address ............................................. 0x%016lx\n" :
    "DMAR address ............................................. 0x%08x\n",
    Dmar
    ));

  DEBUG ((DEBUG_INFO,
    "  Table Contents:\n"
    ));
  DEBUG ((DEBUG_INFO,
    "    Host Address Width ................................... 0x%02x\n",
    Dmar->HostAddressWidth
    ));
  DEBUG ((DEBUG_INFO,
    "    Flags ................................................ 0x%02x\n",
    Dmar->Flags
    ));
  DEBUG ((DEBUG_INFO,
    "      INTR_REMAP ......................................... 0x%02x\n",
    Dmar->Flags & EFI_ACPI_DMAR_FLAGS_INTR_REMAP
    ));
  DEBUG ((DEBUG_INFO,
    "      X2APIC_OPT_OUT_SET ................................. 0x%02x\n",
    Dmar->Flags & EFI_ACPI_DMAR_FLAGS_X2APIC_OPT_OUT
    ));

  DmarLen  = Dmar->Header.Length - sizeof(EFI_ACPI_DMAR_HEADER);
  DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)(Dmar + 1);
  while (DmarLen > 0) {
    switch (DmarHeader->Type) {
    case EFI_ACPI_DMAR_TYPE_DRHD:
      DumpDmarDrhd ((EFI_ACPI_DMAR_DRHD_HEADER *)DmarHeader);
      break;
    case EFI_ACPI_DMAR_TYPE_RMRR:
      DumpDmarRmrr ((EFI_ACPI_DMAR_RMRR_HEADER *)DmarHeader);
      break;
    default:
      break;
    }
    DmarLen -= DmarHeader->Length;
    DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)DmarHeader + DmarHeader->Length);
  }

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

  return;
}

/**
  Get VTd engine number.

  @param[in]  AcpiDmarTable  DMAR ACPI table

  @return the VTd engine number.
**/
UINTN
GetVtdEngineNumber (
  IN EFI_ACPI_DMAR_HEADER                    *AcpiDmarTable
  )
{
  EFI_ACPI_DMAR_STRUCTURE_HEADER                    *DmarHeader;
  UINTN                                             VtdIndex;

  VtdIndex = 0;
  DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)(AcpiDmarTable + 1));
  while ((UINTN)DmarHeader < (UINTN)AcpiDmarTable + AcpiDmarTable->Header.Length) {
    switch (DmarHeader->Type) {
    case EFI_ACPI_DMAR_TYPE_DRHD:
      VtdIndex++;
      break;
    default:
      break;
    }
    DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)DmarHeader + DmarHeader->Length);
  }
  return VtdIndex ;
}

/**
  Process DMAR DHRD table.

  @param[in]  VTdInfo   The VTd engine context information.
  @param[in]  VtdIndex  The index of VTd engine.
  @param[in]  DmarDrhd  The DRHD table.
**/
VOID
ProcessDhrd (
  IN VTD_INFO                   *VTdInfo,
  IN UINTN                      VtdIndex,
  IN EFI_ACPI_DMAR_DRHD_HEADER  *DmarDrhd
  )
{
  DEBUG ((DEBUG_INFO,"  VTD (%d) BaseAddress -  0x%016lx\n", VtdIndex, DmarDrhd->RegisterBaseAddress));
  VTdInfo->VTdEngineAddress[VtdIndex] = DmarDrhd->RegisterBaseAddress;
}

/**
  Parse DMAR DRHD table.

  @param[in]  AcpiDmarTable  DMAR ACPI table

  @return EFI_SUCCESS  The DMAR DRHD table is parsed.
**/
EFI_STATUS
ParseDmarAcpiTableDrhd (
  IN EFI_ACPI_DMAR_HEADER                    *AcpiDmarTable
  )
{
  EFI_ACPI_DMAR_STRUCTURE_HEADER                    *DmarHeader;
  UINTN                                             VtdUnitNumber;
  UINTN                                             VtdIndex;
  VTD_INFO                                          *VTdInfo;

  VtdUnitNumber = GetVtdEngineNumber (AcpiDmarTable);
  if (VtdUnitNumber == 0) {
    return EFI_UNSUPPORTED;
  }

  VTdInfo = BuildGuidHob (&mVTdInfoGuid, sizeof(VTD_INFO) + (VtdUnitNumber - 1) * sizeof(UINT64));
  ASSERT(VTdInfo != NULL);
  if (VTdInfo == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  //
  // Initialize the engine mask to all.
  //
  VTdInfo->AcpiDmarTable    = AcpiDmarTable;
  VTdInfo->EngineMask       = LShiftU64 (1, VtdUnitNumber) - 1;
  VTdInfo->HostAddressWidth = AcpiDmarTable->HostAddressWidth;
  VTdInfo->VTdEngineCount   = VtdUnitNumber;

  VtdIndex = 0;
  DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)(AcpiDmarTable + 1));
  while ((UINTN)DmarHeader < (UINTN)AcpiDmarTable + AcpiDmarTable->Header.Length) {
    switch (DmarHeader->Type) {
    case EFI_ACPI_DMAR_TYPE_DRHD:
      ASSERT (VtdIndex < VtdUnitNumber);
      ProcessDhrd (VTdInfo, VtdIndex, (EFI_ACPI_DMAR_DRHD_HEADER *)DmarHeader);
      VtdIndex++;

      break;

    default:
      break;
    }
    DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)DmarHeader + DmarHeader->Length);
  }
  ASSERT (VtdIndex == VtdUnitNumber);

  return EFI_SUCCESS;
}

/**
  Return the VTd engine index according to the Segment and DevScopeEntry.

  @param AcpiDmarTable   DMAR ACPI table
  @param Segment         The segment of the VTd engine
  @param DevScopeEntry   The DevScopeEntry of the VTd engine

  @return The VTd engine index according to the Segment and DevScopeEntry.
  @retval -1  The VTd engine is not found.
**/
UINTN
GetVTdEngineFromDevScopeEntry (
  IN  EFI_ACPI_DMAR_HEADER                        *AcpiDmarTable,
  IN  UINT16                                      Segment,
  IN  EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *DevScopeEntry
  )
{
  EFI_ACPI_DMAR_STRUCTURE_HEADER                    *DmarHeader;
  UINTN                                             VtdIndex;
  EFI_ACPI_DMAR_DRHD_HEADER                         *DmarDrhd;
  EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER       *ThisDevScopeEntry;

  VtdIndex = 0;
  DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)(AcpiDmarTable + 1));
  while ((UINTN)DmarHeader < (UINTN)AcpiDmarTable + AcpiDmarTable->Header.Length) {
    switch (DmarHeader->Type) {
    case EFI_ACPI_DMAR_TYPE_DRHD:
      DmarDrhd = (EFI_ACPI_DMAR_DRHD_HEADER *)DmarHeader;
      if (DmarDrhd->SegmentNumber != Segment) {
        // Mismatch
        break;
      }
      if ((DmarDrhd->Header.Length == sizeof(EFI_ACPI_DMAR_DRHD_HEADER)) ||
          ((DmarDrhd->Flags & EFI_ACPI_DMAR_DRHD_FLAGS_INCLUDE_PCI_ALL) != 0)) {
        // No DevScopeEntry
        // Do not handle PCI_ALL
        break;
      }
      ThisDevScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)(DmarDrhd + 1));
      while ((UINTN)ThisDevScopeEntry < (UINTN)DmarDrhd + DmarDrhd->Header.Length) {
        if ((ThisDevScopeEntry->Length == DevScopeEntry->Length) &&
            (CompareMem (ThisDevScopeEntry, DevScopeEntry, DevScopeEntry->Length) == 0)) {
          return VtdIndex;
        }
        ThisDevScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)ThisDevScopeEntry + ThisDevScopeEntry->Length);
      }
      break;
    default:
      break;
    }
    DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)DmarHeader + DmarHeader->Length);
  }
  return (UINTN)-1;
}

/**
  Process DMAR RMRR table.

  @param[in]  VTdInfo   The VTd engine context information.
  @param[in]  DmarRmrr  The RMRR table.
**/
VOID
ProcessRmrr (
  IN VTD_INFO                   *VTdInfo,
  IN EFI_ACPI_DMAR_RMRR_HEADER  *DmarRmrr
  )
{
  EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER       *DmarDevScopeEntry;
  UINTN                                             VTdIndex;
  UINT64                                            RmrrMask;
  UINTN                                             LowBottom;
  UINTN                                             LowTop;
  UINTN                                             HighBottom;
  UINT64                                            HighTop;
  EFI_ACPI_DMAR_HEADER                              *AcpiDmarTable;

  AcpiDmarTable = VTdInfo->AcpiDmarTable;

  DEBUG ((DEBUG_INFO,"  RMRR (Base 0x%016lx, Limit 0x%016lx)\n", DmarRmrr->ReservedMemoryRegionBaseAddress, DmarRmrr->ReservedMemoryRegionLimitAddress));

  if ((DmarRmrr->ReservedMemoryRegionBaseAddress == 0) ||
      (DmarRmrr->ReservedMemoryRegionLimitAddress == 0)) {
    return ;
  }

  DmarDevScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)(DmarRmrr + 1));
  while ((UINTN)DmarDevScopeEntry < (UINTN)DmarRmrr + DmarRmrr->Header.Length) {
    ASSERT (DmarDevScopeEntry->Type == EFI_ACPI_DEVICE_SCOPE_ENTRY_TYPE_PCI_ENDPOINT);

    VTdIndex = GetVTdEngineFromDevScopeEntry (AcpiDmarTable, DmarRmrr->SegmentNumber, DmarDevScopeEntry);
    if (VTdIndex != (UINTN)-1) {
      RmrrMask = LShiftU64 (1, VTdIndex);

      LowBottom = 0;
      LowTop = (UINTN)DmarRmrr->ReservedMemoryRegionBaseAddress;
      HighBottom = (UINTN)DmarRmrr->ReservedMemoryRegionLimitAddress + 1;
      HighTop = GetTopMemory ();

      SetDmaProtectedRange (
        VTdInfo,
        RmrrMask,
        0,
        (UINT32)(LowTop - LowBottom),
        HighBottom,
        HighTop - HighBottom
        );

      //
      // Remove the engine from the engine mask.
      // The assumption is that any other PEI driver does not access
      // the device covered by this engine.
      //
      VTdInfo->EngineMask = VTdInfo->EngineMask & (~RmrrMask);
    }

    DmarDevScopeEntry = (EFI_ACPI_DMAR_DEVICE_SCOPE_STRUCTURE_HEADER *)((UINTN)DmarDevScopeEntry + DmarDevScopeEntry->Length);
  }
}

/**
  Parse DMAR DRHD table.

  @param[in]  VTdInfo   The VTd engine context information.
**/
VOID
ParseDmarAcpiTableRmrr (
  IN VTD_INFO                    *VTdInfo
  )
{
  EFI_ACPI_DMAR_HEADER                    *AcpiDmarTable;
  EFI_ACPI_DMAR_STRUCTURE_HEADER          *DmarHeader;

  AcpiDmarTable = VTdInfo->AcpiDmarTable;

  DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)(AcpiDmarTable + 1));
  while ((UINTN)DmarHeader < (UINTN)AcpiDmarTable + AcpiDmarTable->Header.Length) {
    switch (DmarHeader->Type) {
    case EFI_ACPI_DMAR_TYPE_RMRR:
      ProcessRmrr (VTdInfo, (EFI_ACPI_DMAR_RMRR_HEADER *)DmarHeader);
      break;
    default:
      break;
    }
    DmarHeader = (EFI_ACPI_DMAR_STRUCTURE_HEADER *)((UINTN)DmarHeader + DmarHeader->Length);
  }
}