/** @file
  This driver installs Single Segment Pci Configuration 2 PPI 
  to provide read, write and modify access to Pci configuration space in PEI phase. 
  To follow PI specification, these services also support access to the unaligned Pci address.

  Copyright (c) 2006 - 2010, Intel Corporation
  All rights reserved. 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 <PiPei.h>
#include <Ppi/PciCfg2.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/PciLib.h>
#include <Library/PeimEntryPoint.h>
#include <Library/PeiServicesLib.h>
#include <IndustryStandard/Pci.h>

/**
   Convert EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS to PCI_LIB_ADDRESS.

   @param Address   PCI address with EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS format.

   @return PCI address with PCI_LIB_ADDRESS format.

**/
UINTN
PciCfgAddressConvert (
  EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS *Address
  )
{
  if (Address->ExtendedRegister == 0) {
    return PCI_LIB_ADDRESS (Address->Bus, Address->Device, Address->Function, Address->Register);
  }

  return PCI_LIB_ADDRESS (Address->Bus, Address->Device, Address->Function, Address->ExtendedRegister);
}

/**
  Reads from a given location in the PCI configuration space.

  @param  PeiServices     An indirect pointer to the PEI Services Table published by the PEI Foundation.
  @param  This            Pointer to local data for the interface.
  @param  Width           The width of the access. Enumerated in bytes.
                          See EFI_PEI_PCI_CFG_PPI_WIDTH above.
  @param  Address         The physical address of the access. The format of
                          the address is described by EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS.
  @param  Buffer          A pointer to the buffer of data.

  @retval EFI_SUCCESS           The function completed successfully.
  @retval EFI_INVALID_PARAMETER The invalid access width.
  
**/
EFI_STATUS
EFIAPI
PciCfg2Read (
  IN CONST  EFI_PEI_SERVICES          **PeiServices,
  IN CONST  EFI_PEI_PCI_CFG2_PPI      *This,
  IN        EFI_PEI_PCI_CFG_PPI_WIDTH Width,
  IN        UINT64                    Address,
  IN OUT    VOID                      *Buffer
  )
{
  UINTN  PciLibAddress;

  PciLibAddress = PciCfgAddressConvert ((EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS *) &Address);

  if (Width == EfiPeiPciCfgWidthUint8) {
    *((UINT8 *) Buffer) = PciRead8 (PciLibAddress);
  } else if (Width == EfiPeiPciCfgWidthUint16) {
    if ((PciLibAddress & 0x01) == 0) {
      //
      // Aligned Pci address access
      //
      WriteUnaligned16 (((UINT16 *) Buffer), PciRead16 (PciLibAddress));
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      *((UINT8 *) Buffer) = PciRead8 (PciLibAddress);
      *((UINT8 *) Buffer + 1) = PciRead8 (PciLibAddress + 1);
    }
  } else if (Width == EfiPeiPciCfgWidthUint32) {
    if ((PciLibAddress & 0x03) == 0) {
      //
      // Aligned Pci address access
      //
      WriteUnaligned32 (((UINT32 *) Buffer), PciRead32 (PciLibAddress));
    } else if ((PciLibAddress & 0x01) == 0) {
      //
      // Unaligned Pci address access, break up the request into word by word.
      //
      WriteUnaligned16 (((UINT16 *) Buffer), PciRead16 (PciLibAddress));
      WriteUnaligned16 (((UINT16 *) Buffer + 1), PciRead16 (PciLibAddress + 2));
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      *((UINT8 *) Buffer) = PciRead8 (PciLibAddress);
      *((UINT8 *) Buffer + 1) = PciRead8 (PciLibAddress + 1);
      *((UINT8 *) Buffer + 2) = PciRead8 (PciLibAddress + 2);
      *((UINT8 *) Buffer + 3) = PciRead8 (PciLibAddress + 3);
    }
  } else {
    return EFI_INVALID_PARAMETER;
  }

  return EFI_SUCCESS;
}

/**
  Write to a given location in the PCI configuration space.

  @param  PeiServices     An indirect pointer to the PEI Services Table published by the PEI Foundation.
  @param  This            Pointer to local data for the interface.
  @param  Width           The width of the access. Enumerated in bytes.
                          See EFI_PEI_PCI_CFG_PPI_WIDTH above.
  @param  Address         The physical address of the access. The format of
                          the address is described by EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS.
  @param  Buffer          A pointer to the buffer of data.

  @retval EFI_SUCCESS           The function completed successfully.
  @retval EFI_INVALID_PARAMETER The invalid access width.

**/
EFI_STATUS
EFIAPI
PciCfg2Write (
  IN CONST  EFI_PEI_SERVICES          **PeiServices,
  IN CONST  EFI_PEI_PCI_CFG2_PPI      *This,
  IN        EFI_PEI_PCI_CFG_PPI_WIDTH Width,
  IN        UINT64                    Address,
  IN OUT    VOID                      *Buffer
  )
{
  UINTN  PciLibAddress;

  PciLibAddress = PciCfgAddressConvert ((EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS *) &Address);

  if (Width == EfiPeiPciCfgWidthUint8) {
    PciWrite8 (PciLibAddress, *((UINT8 *) Buffer));
  } else if (Width == EfiPeiPciCfgWidthUint16) {
    if ((PciLibAddress & 0x01) == 0) {
      //
      // Aligned Pci address access
      //
      PciWrite16 (PciLibAddress, ReadUnaligned16 ((UINT16 *) Buffer));
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      PciWrite8 (PciLibAddress, *((UINT8 *) Buffer));
      PciWrite8 (PciLibAddress + 1, *((UINT8 *) Buffer + 1)); 
    }
  } else if (Width == EfiPeiPciCfgWidthUint32) {
    if ((PciLibAddress & 0x03) == 0) {
      //
      // Aligned Pci address access
      //
      PciWrite32 (PciLibAddress, ReadUnaligned32 ((UINT32 *) Buffer));
    } else if ((PciLibAddress & 0x01) == 0) {
      //
      // Unaligned Pci address access, break up the request into word by word.
      //
      PciWrite16 (PciLibAddress, ReadUnaligned16 ((UINT16 *) Buffer));
      PciWrite16 (PciLibAddress + 2, ReadUnaligned16 ((UINT16 *) Buffer + 1));
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      PciWrite8 (PciLibAddress, *((UINT8 *) Buffer));
      PciWrite8 (PciLibAddress + 1, *((UINT8 *) Buffer + 1)); 
      PciWrite8 (PciLibAddress + 2, *((UINT8 *) Buffer + 2)); 
      PciWrite8 (PciLibAddress + 3, *((UINT8 *) Buffer + 3)); 
    }
  } else {
    return EFI_INVALID_PARAMETER;
  }

  return EFI_SUCCESS;
}


/**
  This function performs a read-modify-write operation on the contents from a given
  location in the PCI configuration space.

  @param  PeiServices     An indirect pointer to the PEI Services Table
                          published by the PEI Foundation.
  @param  This            Pointer to local data for the interface.
  @param  Width           The width of the access. Enumerated in bytes. Type
                          EFI_PEI_PCI_CFG_PPI_WIDTH is defined in Read().
  @param  Address         The physical address of the access.
  @param  SetBits         Points to value to bitwise-OR with the read configuration value.
                          The size of the value is determined by Width.
  @param  ClearBits       Points to the value to negate and bitwise-AND with the read configuration value.
                          The size of the value is determined by Width.

  @retval EFI_SUCCESS           The function completed successfully.
  @retval EFI_INVALID_PARAMETER The invalid access width.

**/
EFI_STATUS
EFIAPI
PciCfg2Modify (
  IN CONST  EFI_PEI_SERVICES          **PeiServices,
  IN CONST  EFI_PEI_PCI_CFG2_PPI      *This,
  IN        EFI_PEI_PCI_CFG_PPI_WIDTH Width,
  IN        UINT64                    Address,
  IN        VOID                      *SetBits,
  IN        VOID                      *ClearBits
  )
{
  UINTN   PciLibAddress;
  UINT16  ClearValue16;
  UINT16  SetValue16;
  UINT32  ClearValue32;
  UINT32  SetValue32;

  PciLibAddress = PciCfgAddressConvert ((EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS *) &Address);

  if (Width == EfiPeiPciCfgWidthUint8) {
    PciAndThenOr8 (PciLibAddress, (UINT8) (~(*(UINT8 *) ClearBits)), *((UINT8 *) SetBits));
  } else if (Width == EfiPeiPciCfgWidthUint16) {
    if ((PciLibAddress & 0x01) == 0) {
      //
      // Aligned Pci address access
      //
      ClearValue16  = (UINT16) (~ReadUnaligned16 ((UINT16 *) ClearBits));
      SetValue16    = ReadUnaligned16 ((UINT16 *) SetBits);
      PciAndThenOr16 (PciLibAddress, ClearValue16, SetValue16);
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      PciAndThenOr8 (PciLibAddress, (UINT8) (~(*(UINT8 *) ClearBits)), *((UINT8 *) SetBits));
      PciAndThenOr8 (PciLibAddress + 1, (UINT8) (~(*((UINT8 *) ClearBits + 1))), *((UINT8 *) SetBits + 1));
    }
  } else if (Width == EfiPeiPciCfgWidthUint32) {
    if ((PciLibAddress & 0x03) == 0) {
      //
      // Aligned Pci address access
      //
      ClearValue32  = (UINT32) (~ReadUnaligned32 ((UINT32 *) ClearBits));
      SetValue32    = ReadUnaligned32 ((UINT32 *) SetBits);
      PciAndThenOr32 (PciLibAddress, ClearValue32, SetValue32);
    } else if ((PciLibAddress & 0x01) == 0) {
      //
      // Unaligned Pci address access, break up the request into word by word.
      //
      ClearValue16  = (UINT16) (~ReadUnaligned16 ((UINT16 *) ClearBits));
      SetValue16    = ReadUnaligned16 ((UINT16 *) SetBits);
      PciAndThenOr16 (PciLibAddress, ClearValue16, SetValue16);

      ClearValue16  = (UINT16) (~ReadUnaligned16 ((UINT16 *) ClearBits + 1));
      SetValue16    = ReadUnaligned16 ((UINT16 *) SetBits + 1);
      PciAndThenOr16 (PciLibAddress + 2, ClearValue16, SetValue16);
    } else {
      //
      // Unaligned Pci address access, break up the request into byte by byte.
      //
      PciAndThenOr8 (PciLibAddress, (UINT8) (~(*(UINT8 *) ClearBits)), *((UINT8 *) SetBits));
      PciAndThenOr8 (PciLibAddress + 1, (UINT8) (~(*((UINT8 *) ClearBits + 1))), *((UINT8 *) SetBits + 1));
      PciAndThenOr8 (PciLibAddress + 2, (UINT8) (~(*((UINT8 *) ClearBits + 2))), *((UINT8 *) SetBits + 2));
      PciAndThenOr8 (PciLibAddress + 3, (UINT8) (~(*((UINT8 *) ClearBits + 3))), *((UINT8 *) SetBits + 3));
    }
  } else {
    return EFI_INVALID_PARAMETER;
  }

  return EFI_SUCCESS;
}

EFI_PEI_PCI_CFG2_PPI gPciCfg2Ppi = {
  PciCfg2Read,
  PciCfg2Write,
  PciCfg2Modify,
  0
};

EFI_PEI_PPI_DESCRIPTOR gPciCfg2PpiList = {
  (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  &gEfiPciCfg2PpiGuid,
  &gPciCfg2Ppi
};

/**
  Module's entry function. 
  This routine will install EFI_PEI_PCI_CFG2_PPI.
  
  @param  FileHandle  Handle of the file being invoked.
  @param  PeiServices Describes the list of possible PEI Services.

  @return Whether success to install service.
**/
EFI_STATUS
EFIAPI
PeimInitializePciCfg (
  IN       EFI_PEI_FILE_HANDLE  FileHandle,
  IN CONST EFI_PEI_SERVICES     **PeiServices
  )
{
  EFI_STATUS            Status;

  (**(EFI_PEI_SERVICES **)PeiServices).PciCfg = &gPciCfg2Ppi;
  Status = PeiServicesInstallPpi (&gPciCfg2PpiList);
  ASSERT_EFI_ERROR (Status);

  return Status;
}