/** @file
  FADT table parser

  Copyright (c) 2016 - 2020, ARM Limited. All rights reserved.
  SPDX-License-Identifier: BSD-2-Clause-Patent

  @par Reference(s):
    - ACPI 6.3 Specification - January 2019
**/

#include <IndustryStandard/Acpi.h>
#include <Library/UefiLib.h>
#include "AcpiParser.h"
#include "AcpiTableParser.h"
#include "AcpiView.h"

// Local variables
STATIC CONST UINT32* DsdtAddress;
STATIC CONST UINT64* X_DsdtAddress;
STATIC CONST UINT32* Flags;
STATIC CONST UINT32* FirmwareCtrl;
STATIC CONST UINT64* X_FirmwareCtrl;
STATIC CONST UINT8*  FadtMinorRevision;
STATIC ACPI_DESCRIPTION_HEADER_INFO AcpiHdrInfo;

/**
  A macro defining the Hardware reduced ACPI flag
**/
#define HW_REDUCED_ACPI   BIT20

/**
  Offset to the FACS signature from the start of the FACS.
**/
#define FACS_SIGNATURE_OFFSET   0

/**
  Offset to the FACS revision from the start of the FACS.
**/
#define FACS_VERSION_OFFSET     32

/**
  Offset to the FACS length from the start of the FACS.
**/
#define FACS_LENGTH_OFFSET      4

/**
  Get the ACPI XSDT header info.
**/
CONST ACPI_DESCRIPTION_HEADER_INFO *
EFIAPI
GetAcpiXsdtHeaderInfo (
  VOID
  );

/**
  This function validates the Firmware Control Field.

  @param [in] Ptr     Pointer to the start of the field data.
  @param [in] Context Pointer to context specific information e.g. this
                      could be a pointer to the ACPI table header.
**/
STATIC
VOID
EFIAPI
ValidateFirmwareCtrl (
  IN UINT8* Ptr,
  IN VOID*  Context
)
{
#if defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64)
  if (*(UINT32*)Ptr != 0) {
    IncrementErrorCount ();
    Print (
      L"\nERROR: Firmware Control must be zero for ARM platforms."
    );
  }
#endif
}

/**
  This function validates the X_Firmware Control Field.

  @param [in] Ptr     Pointer to the start of the field data.
  @param [in] Context Pointer to context specific information e.g. this
                      could be a pointer to the ACPI table header.
**/
STATIC
VOID
EFIAPI
ValidateXFirmwareCtrl (
  IN UINT8* Ptr,
  IN VOID*  Context
)
{
#if defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64)
  if (*(UINT64*)Ptr != 0) {
    IncrementErrorCount ();
    Print (
      L"\nERROR: X Firmware Control must be zero for ARM platforms."
    );
  }
#endif
}

/**
  This function validates the flags.

  @param [in] Ptr     Pointer to the start of the field data.
  @param [in] Context Pointer to context specific information e.g. this
                      could be a pointer to the ACPI table header.
**/
STATIC
VOID
EFIAPI
ValidateFlags (
  IN UINT8* Ptr,
  IN VOID*  Context
)
{
#if defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64)
  if (((*(UINT32*)Ptr) & HW_REDUCED_ACPI) == 0) {
    IncrementErrorCount ();
    Print (
      L"\nERROR: HW_REDUCED_ACPI flag must be set for ARM platforms."
    );
  }
#endif
}

/**
  An ACPI_PARSER array describing the ACPI FADT Table.
**/
STATIC CONST ACPI_PARSER FadtParser[] = {
  PARSE_ACPI_HEADER (&AcpiHdrInfo),
  {L"FIRMWARE_CTRL", 4, 36, L"0x%x", NULL, (VOID**)&FirmwareCtrl,
    ValidateFirmwareCtrl, NULL},
  {L"DSDT", 4, 40, L"0x%x", NULL, (VOID**)&DsdtAddress, NULL, NULL},
  {L"Reserved", 1, 44, L"%x", NULL, NULL, NULL, NULL},
  {L"Preferred_PM_Profile", 1, 45, L"0x%x", NULL, NULL, NULL, NULL},
  {L"SCI_INT", 2, 46, L"0x%x", NULL, NULL, NULL, NULL},
  {L"SMI_CMD", 4, 48, L"0x%x", NULL, NULL, NULL, NULL},
  {L"ACPI_ENABLE", 1, 52, L"0x%x", NULL, NULL, NULL, NULL},
  {L"ACPI_DISABLE", 1, 53, L"0x%x", NULL, NULL, NULL, NULL},
  {L"S4BIOS_REQ", 1, 54, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PSTATE_CNT", 1, 55, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1a_EVT_BLK", 4, 56, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1b_EVT_BLK", 4, 60, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1a_CNT_BLK", 4, 64, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1b_CNT_BLK", 4, 68, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM2_CNT_BLK", 4, 72, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM_TMR_BLK", 4, 76, L"0x%x", NULL, NULL, NULL, NULL},
  {L"GPE0_BLK", 4, 80, L"0x%x", NULL, NULL, NULL, NULL},
  {L"GPE1_BLK", 4, 84, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1_EVT_LEN", 1, 88, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM1_CNT_LEN", 1, 89, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM2_CNT_LEN", 1, 90, L"0x%x", NULL, NULL, NULL, NULL},
  {L"PM_TMR_LEN", 1, 91, L"0x%x", NULL, NULL, NULL, NULL},
  {L"GPE0_BLK_LEN", 1, 92, L"0x%x", NULL, NULL, NULL, NULL},
  {L"GPE1_BLK_LEN", 1, 93, L"0x%x", NULL, NULL, NULL, NULL},
  {L"GPE1_BASE", 1, 94, L"0x%x", NULL, NULL, NULL, NULL},
  {L"CST_CNT", 1, 95, L"0x%x", NULL, NULL, NULL, NULL},
  {L"P_LVL2_LAT", 2, 96, L"0x%x", NULL, NULL, NULL, NULL},
  {L"P_LVL3_LAT", 2, 98, L"0x%x", NULL, NULL, NULL, NULL},
  {L"FLUSH_SIZE", 2, 100, L"0x%x", NULL, NULL, NULL, NULL},
  {L"FLUSH_STRIDE", 2, 102, L"0x%x", NULL, NULL, NULL, NULL},
  {L"DUTY_OFFSET", 1, 104, L"0x%x", NULL, NULL, NULL, NULL},
  {L"DUTY_WIDTH", 1, 105, L"0x%x", NULL, NULL, NULL, NULL},
  {L"DAY_ALRM", 1, 106, L"0x%x", NULL, NULL, NULL, NULL},
  {L"MON_ALRM", 1, 107, L"0x%x", NULL, NULL, NULL, NULL},
  {L"CENTURY", 1, 108, L"0x%x", NULL, NULL, NULL, NULL},
  {L"IAPC_BOOT_ARCH", 2, 109, L"0x%x", NULL, NULL, NULL, NULL},
  {L"Reserved", 1, 111, L"0x%x", NULL, NULL, NULL, NULL},
  {L"Flags", 4, 112, L"0x%x", NULL, (VOID**)&Flags, ValidateFlags, NULL},
  {L"RESET_REG", 12, 116, NULL, DumpGas, NULL, NULL, NULL},
  {L"RESET_VALUE", 1, 128, L"0x%x", NULL, NULL, NULL, NULL},
  {L"ARM_BOOT_ARCH", 2, 129, L"0x%x", NULL, NULL, NULL, NULL},
  {L"FADT Minor Version", 1, 131, L"0x%x", NULL, (VOID**)&FadtMinorRevision,
    NULL, NULL},
  {L"X_FIRMWARE_CTRL", 8, 132, L"0x%lx", NULL, (VOID**)&X_FirmwareCtrl,
    ValidateXFirmwareCtrl, NULL},
  {L"X_DSDT", 8, 140, L"0x%lx", NULL, (VOID**)&X_DsdtAddress, NULL, NULL},
  {L"X_PM1a_EVT_BLK", 12, 148, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_PM1b_EVT_BLK", 12, 160, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_PM1a_CNT_BLK", 12, 172, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_PM1b_CNT_BLK", 12, 184, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_PM2_CNT_BLK", 12, 196, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_PM_TMR_BLK", 12, 208, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_GPE0_BLK", 12, 220, NULL, DumpGas, NULL, NULL, NULL},
  {L"X_GPE1_BLK", 12, 232, NULL, DumpGas, NULL, NULL, NULL},
  {L"SLEEP_CONTROL_REG", 12, 244, NULL, DumpGas, NULL, NULL, NULL},
  {L"SLEEP_STATUS_REG", 12, 256, NULL, DumpGas, NULL, NULL, NULL},
  {L"Hypervisor VendorIdentity", 8, 268, L"%lx", NULL, NULL, NULL, NULL}
};

/**
  This function parses the ACPI FADT table.
  This function parses the FADT table and optionally traces the ACPI table fields.

  This function also performs validation of the ACPI table fields.

  @param [in] Trace              If TRUE, trace the ACPI fields.
  @param [in] Ptr                Pointer to the start of the buffer.
  @param [in] AcpiTableLength    Length of the ACPI table.
  @param [in] AcpiTableRevision  Revision of the ACPI table.
**/
VOID
EFIAPI
ParseAcpiFadt (
  IN BOOLEAN Trace,
  IN UINT8*  Ptr,
  IN UINT32  AcpiTableLength,
  IN UINT8   AcpiTableRevision
  )
{
  EFI_STATUS              Status;
  UINT8*                  DsdtPtr;
  UINT8*                  FirmwareCtrlPtr;
  UINT32                  FacsSignature;
  UINT32                  FacsLength;
  UINT8                   FacsRevision;
  PARSE_ACPI_TABLE_PROC   FacsParserProc;

  ParseAcpi (
    Trace,
    0,
    "FADT",
    Ptr,
    AcpiTableLength,
    PARSER_PARAMS (FadtParser)
    );

  if (Trace) {
    if (FadtMinorRevision != NULL) {
      Print (L"\nSummary:\n");
      PrintFieldName (2, L"FADT Version");
      Print (L"%d.%d\n",  *AcpiHdrInfo.Revision, *FadtMinorRevision);
    }

    if (*GetAcpiXsdtHeaderInfo ()->OemTableId != *AcpiHdrInfo.OemTableId) {
      IncrementErrorCount ();
      Print (L"ERROR: OEM Table Id does not match with RSDT/XSDT.\n");
    }
  }

  // If X_FIRMWARE_CTRL is not zero then use X_FIRMWARE_CTRL and ignore
  // FIRMWARE_CTRL, else use FIRMWARE_CTRL.
  if ((X_FirmwareCtrl != NULL) && (*X_FirmwareCtrl != 0)) {
    FirmwareCtrlPtr = (UINT8*)(UINTN)(*X_FirmwareCtrl);
  } else if ((FirmwareCtrl != NULL) && (*FirmwareCtrl != 0)) {
    FirmwareCtrlPtr = (UINT8*)(UINTN)(*FirmwareCtrl);
  } else {
    FirmwareCtrlPtr = NULL;
    // if HW_REDUCED_ACPI flag is not set, both FIRMWARE_CTRL and
    // X_FIRMWARE_CTRL cannot be zero, and the FACS Table must be
    // present.
    if ((Trace) &&
        (Flags != NULL) &&
        ((*Flags & EFI_ACPI_6_3_HW_REDUCED_ACPI) != EFI_ACPI_6_3_HW_REDUCED_ACPI)) {
      IncrementErrorCount ();
      Print (L"ERROR: No FACS table found, "
               L"both X_FIRMWARE_CTRL and FIRMWARE_CTRL are zero.\n");
    }
  }

  if (FirmwareCtrlPtr != NULL) {
    // The FACS table does not have a standard ACPI table header. Therefore,
    // the signature, length and version needs to be initially parsed.
    // The FACS signature is 4 bytes starting at offset 0.
    FacsSignature = *(UINT32*)(FirmwareCtrlPtr + FACS_SIGNATURE_OFFSET);

    // The FACS length is 4 bytes starting at offset 4.
    FacsLength = *(UINT32*)(FirmwareCtrlPtr + FACS_LENGTH_OFFSET);

    // The FACS version is 1 byte starting at offset 32.
    FacsRevision = *(UINT8*)(FirmwareCtrlPtr + FACS_VERSION_OFFSET);

    Trace = ProcessTableReportOptions (
              FacsSignature,
              FirmwareCtrlPtr,
              FacsLength
              );

    Status = GetParser (FacsSignature, &FacsParserProc);
    if (EFI_ERROR (Status)) {
      Print (
        L"ERROR: No registered parser found for FACS.\n"
        );
      return;
    }

    FacsParserProc (
      Trace,
      FirmwareCtrlPtr,
      FacsLength,
      FacsRevision
      );
  }

  // If X_DSDT is valid then use X_DSDT and ignore DSDT, else use DSDT.
  if ((X_DsdtAddress != NULL) && (*X_DsdtAddress != 0)) {
    DsdtPtr = (UINT8*)(UINTN)(*X_DsdtAddress);
  } else if ((DsdtAddress != NULL) && (*DsdtAddress != 0)) {
    DsdtPtr = (UINT8*)(UINTN)(*DsdtAddress);
  } else {
    // Both DSDT and X_DSDT cannot be invalid.
#if defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64)
    if (Trace) {
      // The DSDT Table is mandatory for ARM systems
      // as the CPU information MUST be presented in
      // the DSDT.
      IncrementErrorCount ();
      Print (L"ERROR: Both X_DSDT and DSDT are invalid.\n");
    }
#endif
    return;
  }

  ProcessAcpiTable (DsdtPtr);
}