audk/MdePkg/Include/Ppi/PciCfg2.h

/** @file
  This file declares PciCfg2 PPI.

  This ppi Provides platform or chipset-specific access to 
  the PCI configuration space for a specific PCI segment.

  Copyright (c) 2006 - 2009, 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.

  @par Revision Reference:
  This PPI is introduced in PI Version 1.0.

**/

#ifndef __PEI_PCI_CFG2_H__
#define __PEI_PCI_CFG2_H__

#define EFI_PEI_PCI_CFG2_PPI_GUID \
  { 0x57a449a, 0x1fdc, 0x4c06, { 0xbf, 0xc9, 0xf5, 0x3f, 0x6a, 0x99, 0xbb, 0x92 } }


typedef struct _EFI_PEI_PCI_CFG2_PPI   EFI_PEI_PCI_CFG2_PPI;

#define EFI_PEI_PCI_CFG_ADDRESS(bus,dev,func,reg) \
  (((bus) << 24) | \
  ((dev) << 16) | \
  ((func) << 8) | \
  ((reg) < 256 ? (reg) : ((UINT64)(reg) << 32)));

///
/// EFI_PEI_PCI_CFG_PPI_WIDTH
///
typedef enum {
  ///
  ///  8-bit access
  ///
  EfiPeiPciCfgWidthUint8  = 0,
  ///
  /// 16-bit access
  ///
  EfiPeiPciCfgWidthUint16 = 1,
  ///
  /// 32-bit access
  ///
  EfiPeiPciCfgWidthUint32 = 2,
  ///
  /// 64-bit access
  ///
  EfiPeiPciCfgWidthUint64 = 3,
  EfiPeiPciCfgWidthMaximum
} EFI_PEI_PCI_CFG_PPI_WIDTH;

///
/// EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS
///
typedef struct {
  ///
  /// 8-bit register offset within the PCI configuration space for a given device's function
  /// space.
  ///
  UINT8   Register;
  ///
  /// Only the 3 least-significant bits are used to encode one of 8 possible functions within a
  /// given device.
  ///
  UINT8   Function;
  ///
  /// Only the 5 least-significant bits are used to encode one of 32 possible devices.
  ///
  UINT8   Device;
  ///
  /// 8-bit value to encode between 0 and 255 buses.
  ///
  UINT8   Bus;
  ///
  /// Register number in PCI configuration space. If this field is zero, then Register is used
  /// for the register number. If this field is non-zero, then Register is ignored and this field
  /// is used for the register number.
  ///
  UINT32  ExtendedRegister;
} EFI_PEI_PCI_CFG_PPI_PCI_ADDRESS;

/**
  Reads from or 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_DEVICE_ERROR      There was a problem with the transaction.

  @retval EFI_DEVICE_NOT_READY  The device is not capable of supporting the operation at this
                                time.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_PEI_PCI_CFG2_PPI_IO)(
  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
);


/**
  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_DEVICE_ERROR      There was a problem with the transaction.

  @retval EFI_DEVICE_NOT_READY  The device is not capable of supporting
                                the operation at this time.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_PEI_PCI_CFG2_PPI_RW)(
  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
);

///
/// The EFI_PEI_PCI_CFG_PPI interfaces are used to abstract accesses to PCI
/// controllers behind a PCI root bridge controller.
///
struct _EFI_PEI_PCI_CFG2_PPI {
  EFI_PEI_PCI_CFG2_PPI_IO  Read;
  EFI_PEI_PCI_CFG2_PPI_IO  Write;
  EFI_PEI_PCI_CFG2_PPI_RW  Modify;
  ///
  /// The PCI bus segment which the specified functions will access.
  ///
  UINT16                  Segment;
};


extern EFI_GUID gEfiPciCfg2PpiGuid;

#endif