audk/MdePkg/Include/Library/IoLib.h

/** @file
  Provide services to access I/O Ports and MMIO registers.

Copyright (c) 2006 - 2008, Intel Corporation<BR>
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.

**/

#ifndef __IO_LIB_H__
#define __IO_LIB_H__

/**
  Macro that converts PCI Segment and I/O Port to an address that can be
  passed to the I/O Library functions.
  
  Computes an address that is compatible with the I/O Library functions.  
  The unused upper bits of Segment, and Port are stripped prior to the 
  generation of the address.
  
  @param  Segment   PCI Segment number.  Range 0..65535.
  @param  Port      I/O Port number.  Range 0..65535.
  
  @return An address that the I/o Library functions need.

**/

#define IO_LIB_ADDRESS(Segment,Port) \
  ( ((Port) & 0xffff) | (((Segment) & 0xffff) << 16) )

/**
  Reads an 8-bit I/O port.

  Reads the 8-bit I/O port specified by Port. The 8-bit read value is returned.
  This function must guarantee that all I/O read and write operations are
  serialized.

  If 8-bit I/O port operations are not supported, then ASSERT().

  @param  Port  The I/O port to read.

  @return The value read.

**/
UINT8
EFIAPI
IoRead8 (
  IN      UINTN                     Port
  );

/**
  Writes an 8-bit I/O port.

  Writes the 8-bit I/O port specified by Port with the value specified by Value
  and returns Value. This function must guarantee that all I/O read and write
  operations are serialized.

  If 8-bit I/O port operations are not supported, then ASSERT().

  @param  Port  The I/O port to write.
  @param  Value The value to write to the I/O port.

  @return The value written the I/O port.

**/
UINT8
EFIAPI
IoWrite8 (
  IN      UINTN                     Port,
  IN      UINT8                     Value
  );

/**
  Reads an 8-bit I/O port, performs a bitwise OR, and writes the
  result back to the 8-bit I/O port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 8-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized.

  If 8-bit I/O port operations are not supported, then ASSERT().

  @param  Port    The I/O port to write.
  @param  OrData  The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoOr8 (
  IN      UINTN                     Port,
  IN      UINT8                     OrData
  );

/**
  Reads an 8-bit I/O port, performs a bitwise AND, and writes the result back
  to the 8-bit I/O port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 8-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized.

  If 8-bit I/O port operations are not supported, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoAnd8 (
  IN      UINTN                     Port,
  IN      UINT8                     AndData
  );

/**
  Reads an 8-bit I/O port, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 8-bit I/O port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, performs a bitwise OR
  between the result of the AND operation and the value specified by OrData,
  and writes the result to the 8-bit I/O port specified by Port. The value
  written to the I/O port is returned. This function must guarantee that all
  I/O read and write operations are serialized.

  If 8-bit I/O port operations are not supported, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoAndThenOr8 (
  IN      UINTN                     Port,
  IN      UINT8                     AndData,
  IN      UINT8                     OrData
  );

/**
  Reads a bit field of an I/O register.

  Reads the bit field in an 8-bit I/O register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 8-bit I/O port operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.

  @return The value read.

**/
UINT8
EFIAPI
IoBitFieldRead8 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to an I/O register.

  Writes Value to the bit field of the I/O register. The bit field is specified
  by the StartBit and the EndBit. All other bits in the destination I/O
  register are preserved. The value written to the I/O port is returned. 

  If 8-bit I/O port operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  Value     New value of the bit field.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoBitFieldWrite8 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     Value
  );

/**
  Reads a bit field in an 8-bit port, performs a bitwise OR, and writes the
  result back to the bit field in the 8-bit port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 8-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized. Extra left bits in OrData are stripped.

  If 8-bit I/O port operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  OrData    The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoBitFieldOr8 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     OrData
  );

/**
  Reads a bit field in an 8-bit port, performs a bitwise AND, and writes the
  result back to the bit field in the 8-bit port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 8-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized. Extra left bits in AndData are stripped.

  If 8-bit I/O port operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  AndData   The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoBitFieldAnd8 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     AndData
  );

/**
  Reads a bit field in an 8-bit port, performs a bitwise AND followed by a
  bitwise OR, and writes the result back to the bit field in the
  8-bit port.

  Reads the 8-bit I/O port specified by Port, performs a bitwise AND followed
  by a bitwise OR between the read result and the value specified by
  AndData, and writes the result to the 8-bit I/O port specified by Port. The
  value written to the I/O port is returned. This function must guarantee that
  all I/O read and write operations are serialized. Extra left bits in both
  AndData and OrData are stripped.

  If 8-bit I/O port operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  AndData   The value to AND with the read value from the I/O port.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT8
EFIAPI
IoBitFieldAndThenOr8 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     AndData,
  IN      UINT8                     OrData
  );

/**
  Reads a 16-bit I/O port.

  Reads the 16-bit I/O port specified by Port. The 16-bit read value is returned.
  This function must guarantee that all I/O read and write operations are
  serialized.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().

  @param  Port  The I/O port to read.

  @return The value read.

**/
UINT16
EFIAPI
IoRead16 (
  IN      UINTN                     Port
  );

/**
  Writes a 16-bit I/O port.

  Writes the 16-bit I/O port specified by Port with the value specified by Value
  and returns Value. This function must guarantee that all I/O read and write
  operations are serialized.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  
  @param  Port  The I/O port to write.
  @param  Value The value to write to the I/O port.

  @return The value written the I/O port.

**/
UINT16
EFIAPI
IoWrite16 (
  IN      UINTN                     Port,
  IN      UINT16                    Value
  );

/**
  Reads a 16-bit I/O port, performs a bitwise OR, and writes the
  result back to the 16-bit I/O port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 16-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  OrData  The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoOr16 (
  IN      UINTN                     Port,
  IN      UINT16                    OrData
  );

/**
  Reads a 16-bit I/O port, performs a bitwise AND, and writes the result back
  to the 16-bit I/O port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 16-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  
  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoAnd16 (
  IN      UINTN                     Port,
  IN      UINT16                    AndData
  );

/**
  Reads a 16-bit I/O port, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 16-bit I/O port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, performs a bitwise OR
  between the result of the AND operation and the value specified by OrData,
  and writes the result to the 16-bit I/O port specified by Port. The value
  written to the I/O port is returned. This function must guarantee that all
  I/O read and write operations are serialized.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  
  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoAndThenOr16 (
  IN      UINTN                     Port,
  IN      UINT16                    AndData,
  IN      UINT16                    OrData
  );

/**
  Reads a bit field of an I/O register.

  Reads the bit field in a 16-bit I/O register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.

  @return The value read.

**/
UINT16
EFIAPI
IoBitFieldRead16 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to an I/O register.

  Writes Value to the bit field of the I/O register. The bit field is specified
  by the StartBit and the EndBit. All other bits in the destination I/O
  register are preserved. The value written to the I/O port is returned. Extra
  left bits in Value are stripped.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  Value     New value of the bit field.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoBitFieldWrite16 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    Value
  );

/**
  Reads a bit field in a 16-bit port, performs a bitwise OR, and writes the
  result back to the bit field in the 16-bit port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 16-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized. Extra left bits in OrData are stripped.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  OrData    The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoBitFieldOr16 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    OrData
  );

/**
  Reads a bit field in a 16-bit port, performs a bitwise AND, and writes the
  result back to the bit field in the 16-bit port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 16-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized. Extra left bits in AndData are stripped.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  AndData   The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoBitFieldAnd16 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    AndData
  );

/**
  Reads a bit field in a 16-bit port, performs a bitwise AND followed by a
  bitwise OR, and writes the result back to the bit field in the
  16-bit port.

  Reads the 16-bit I/O port specified by Port, performs a bitwise AND followed
  by a bitwise OR between the read result and the value specified by
  AndData, and writes the result to the 16-bit I/O port specified by Port. The
  value written to the I/O port is returned. This function must guarantee that
  all I/O read and write operations are serialized. Extra left bits in both
  AndData and OrData are stripped.

  If 16-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  AndData   The value to AND with the read value from the I/O port.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT16
EFIAPI
IoBitFieldAndThenOr16 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    AndData,
  IN      UINT16                    OrData
  );

/**
  Reads a 32-bit I/O port.

  Reads the 32-bit I/O port specified by Port. The 32-bit read value is returned.
  This function must guarantee that all I/O read and write operations are
  serialized.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  
  @param  Port  The I/O port to read.

  @return The value read.

**/
UINT32
EFIAPI
IoRead32 (
  IN      UINTN                     Port
  );

/**
  Writes a 32-bit I/O port.

  Writes the 32-bit I/O port specified by Port with the value specified by Value
  and returns Value. This function must guarantee that all I/O read and write
  operations are serialized.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  
  @param  Port  The I/O port to write.
  @param  Value The value to write to the I/O port.

  @return The value written the I/O port.

**/
UINT32
EFIAPI
IoWrite32 (
  IN      UINTN                     Port,
  IN      UINT32                    Value
  );

/**
  Reads a 32-bit I/O port, performs a bitwise OR, and writes the
  result back to the 32-bit I/O port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 32-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  OrData  The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoOr32 (
  IN      UINTN                     Port,
  IN      UINT32                    OrData
  );

/**
  Reads a 32-bit I/O port, performs a bitwise AND, and writes the result back
  to the 32-bit I/O port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 32-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoAnd32 (
  IN      UINTN                     Port,
  IN      UINT32                    AndData
  );

/**
  Reads a 32-bit I/O port, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 32-bit I/O port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, performs a bitwise OR
  between the result of the AND operation and the value specified by OrData,
  and writes the result to the 32-bit I/O port specified by Port. The value
  written to the I/O port is returned. This function must guarantee that all
  I/O read and write operations are serialized.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoAndThenOr32 (
  IN      UINTN                     Port,
  IN      UINT32                    AndData,
  IN      UINT32                    OrData
  );

/**
  Reads a bit field of an I/O register.

  Reads the bit field in a 32-bit I/O register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.

  @return The value read.

**/
UINT32
EFIAPI
IoBitFieldRead32 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to an I/O register.

  Writes Value to the bit field of the I/O register. The bit field is specified
  by the StartBit and the EndBit. All other bits in the destination I/O
  register are preserved. The value written to the I/O port is returned. Extra
  left bits in Value are stripped.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  Value     New value of the bit field.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoBitFieldWrite32 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    Value
  );

/**
  Reads a bit field in a 32-bit port, performs a bitwise OR, and writes the
  result back to the bit field in the 32-bit port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 32-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized. Extra left bits in OrData are stripped.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  OrData    The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoBitFieldOr32 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    OrData
  );

/**
  Reads a bit field in a 32-bit port, performs a bitwise AND, and writes the
  result back to the bit field in the 32-bit port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 32-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized. Extra left bits in AndData are stripped.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  AndData   The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoBitFieldAnd32 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    AndData
  );

/**
  Reads a bit field in a 32-bit port, performs a bitwise AND followed by a
  bitwise OR, and writes the result back to the bit field in the
  32-bit port.

  Reads the 32-bit I/O port specified by Port, performs a bitwise AND followed
  by a bitwise OR between the read result and the value specified by
  AndData, and writes the result to the 32-bit I/O port specified by Port. The
  value written to the I/O port is returned. This function must guarantee that
  all I/O read and write operations are serialized. Extra left bits in both
  AndData and OrData are stripped.

  If 32-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  AndData   The value to AND with the read value from the I/O port.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT32
EFIAPI
IoBitFieldAndThenOr32 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    AndData,
  IN      UINT32                    OrData
  );

/**
  Reads a 64-bit I/O port.

  Reads the 64-bit I/O port specified by Port. The 64-bit read value is returned.
  This function must guarantee that all I/O read and write operations are
  serialized.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().

  @param  Port  The I/O port to read.

  @return The value read.

**/
UINT64
EFIAPI
IoRead64 (
  IN      UINTN                     Port
  );

/**
  Writes a 64-bit I/O port.

  Writes the 64-bit I/O port specified by Port with the value specified by Value
  and returns Value. This function must guarantee that all I/O read and write
  operations are serialized.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().

  @param  Port  The I/O port to write.
  @param  Value The value to write to the I/O port.

  @return The value written the I/O port.

**/
UINT64
EFIAPI
IoWrite64 (
  IN      UINTN                     Port,
  IN      UINT64                    Value
  );

/**
  Reads a 64-bit I/O port, performs a bitwise OR, and writes the
  result back to the 64-bit I/O port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 64-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  OrData  The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoOr64 (
  IN      UINTN                     Port,
  IN      UINT64                    OrData
  );

/**
  Reads a 64-bit I/O port, performs a bitwise AND, and writes the result back
  to the 64-bit I/O port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 64-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoAnd64 (
  IN      UINTN                     Port,
  IN      UINT64                    AndData
  );

/**
  Reads a 64-bit I/O port, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 64-bit I/O port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, performs a bitwise OR
  between the result of the AND operation and the value specified by OrData,
  and writes the result to the 64-bit I/O port specified by Port. The value
  written to the I/O port is returned. This function must guarantee that all
  I/O read and write operations are serialized.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().

  @param  Port    The I/O port to write.
  @param  AndData The value to AND with the read value from the I/O port.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoAndThenOr64 (
  IN      UINTN                     Port,
  IN      UINT64                    AndData,
  IN      UINT64                    OrData
  );

/**
  Reads a bit field of an I/O register.

  Reads the bit field in a 64-bit I/O register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.

  @return The value read.

**/
UINT64
EFIAPI
IoBitFieldRead64 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to an I/O register.

  Writes Value to the bit field of the I/O register. The bit field is specified
  by the StartBit and the EndBit. All other bits in the destination I/O
  register are preserved. The value written to the I/O port is returned. Extra
  left bits in Value are stripped.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  Value     New value of the bit field.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoBitFieldWrite64 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    Value
  );

/**
  Reads a bit field in a 64-bit port, performs a bitwise OR, and writes the
  result back to the bit field in the 64-bit port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise OR
  between the read result and the value specified by OrData, and writes the
  result to the 64-bit I/O port specified by Port. The value written to the I/O
  port is returned. This function must guarantee that all I/O read and write
  operations are serialized. Extra left bits in OrData are stripped.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  OrData    The value to OR with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoBitFieldOr64 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    OrData
  );

/**
  Reads a bit field in a 64-bit port, performs a bitwise AND, and writes the
  result back to the bit field in the 64-bit port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise AND between
  the read result and the value specified by AndData, and writes the result to
  the 64-bit I/O port specified by Port. The value written to the I/O port is
  returned. This function must guarantee that all I/O read and write operations
  are serialized. Extra left bits in AndData are stripped.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  AndData   The value to AND with the read value from the I/O port.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoBitFieldAnd64 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    AndData
  );

/**
  Reads a bit field in a 64-bit port, performs a bitwise AND followed by a
  bitwise OR, and writes the result back to the bit field in the
  64-bit port.

  Reads the 64-bit I/O port specified by Port, performs a bitwise AND followed
  by a bitwise OR between the read result and the value specified by
  AndData, and writes the result to the 64-bit I/O port specified by Port. The
  value written to the I/O port is returned. This function must guarantee that
  all I/O read and write operations are serialized. Extra left bits in both
  AndData and OrData are stripped.

  If 64-bit I/O port operations are not supported, then ASSERT().
  If Port is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Port      The I/O port to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  AndData   The value to AND with the read value from the I/O port.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the I/O port.

**/
UINT64
EFIAPI
IoBitFieldAndThenOr64 (
  IN      UINTN                     Port,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    AndData,
  IN      UINT64                    OrData
  );

/**
  Reads an 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address. The 8-bit read value is
  returned. This function must guarantee that all MMIO read and write
  operations are serialized.

  If 8-bit MMIO register operations are not supported, then ASSERT().

  @param  Address The MMIO register to read.

  @return The value read.

**/
UINT8
EFIAPI
MmioRead8 (
  IN      UINTN                     Address
  );

/**
  Writes an 8-bit MMIO register.

  Writes the 8-bit MMIO register specified by Address with the value specified
  by Value and returns Value. This function must guarantee that all MMIO read
  and write operations are serialized.

  If 8-bit MMIO register operations are not supported, then ASSERT().

  @param  Address The MMIO register to write.
  @param  Value   The value to write to the MMIO register.
  
  @return Value.

**/
UINT8
EFIAPI
MmioWrite8 (
  IN      UINTN                     Address,
  IN      UINT8                     Value
  );

/**
  Reads an 8-bit MMIO register, performs a bitwise OR, and writes the
  result back to the 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 8-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized.

  If 8-bit MMIO register operations are not supported, then ASSERT().

  @param  Address The MMIO register to write.
  @param  OrData  The value to OR with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioOr8 (
  IN      UINTN                     Address,
  IN      UINT8                     OrData
  );

/**
  Reads an 8-bit MMIO register, performs a bitwise AND, and writes the result
  back to the 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 8-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized.

  If 8-bit MMIO register operations are not supported, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioAnd8 (
  IN      UINTN                     Address,
  IN      UINT8                     AndData
  );

/**
  Reads an 8-bit MMIO register, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, performs a
  bitwise OR between the result of the AND operation and the value specified by
  OrData, and writes the result to the 8-bit MMIO register specified by
  Address. The value written to the MMIO register is returned. This function
  must guarantee that all MMIO read and write operations are serialized.

  If 8-bit MMIO register operations are not supported, then ASSERT().


  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioAndThenOr8 (
  IN      UINTN                     Address,
  IN      UINT8                     AndData,
  IN      UINT8                     OrData
  );

/**
  Reads a bit field of a MMIO register.

  Reads the bit field in an 8-bit MMIO register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 8-bit MMIO register operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.

  @return The value read.

**/
UINT8
EFIAPI
MmioBitFieldRead8 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to a MMIO register.

  Writes Value to the bit field of the MMIO register. The bit field is
  specified by the StartBit and the EndBit. All other bits in the destination
  MMIO register are preserved. The new value of the 8-bit register is returned.

  If 8-bit MMIO register operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  Value     New value of the bit field.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioBitFieldWrite8 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     Value
  );

/**
  Reads a bit field in an 8-bit MMIO register, performs a bitwise OR, and
  writes the result back to the bit field in the 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 8-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized. Extra left bits in OrData
  are stripped.

  If 8-bit MMIO register operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  OrData    The value to OR with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioBitFieldOr8 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     OrData
  );

/**
  Reads a bit field in an 8-bit MMIO register, performs a bitwise AND, and
  writes the result back to the bit field in the 8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 8-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized. Extra left bits in AndData are
  stripped.

  If 8-bit MMIO register operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  AndData   The value to AND with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioBitFieldAnd8 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     AndData
  );

/**
  Reads a bit field in an 8-bit MMIO register, performs a bitwise AND followed
  by a bitwise OR, and writes the result back to the bit field in the
  8-bit MMIO register.

  Reads the 8-bit MMIO register specified by Address, performs a bitwise AND
  followed by a bitwise OR between the read result and the value
  specified by AndData, and writes the result to the 8-bit MMIO register
  specified by Address. The value written to the MMIO register is returned.
  This function must guarantee that all MMIO read and write operations are
  serialized. Extra left bits in both AndData and OrData are stripped.

  If 8-bit MMIO register operations are not supported, then ASSERT().
  If StartBit is greater than 7, then ASSERT().
  If EndBit is greater than 7, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..7.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..7.
  @param  AndData   The value to AND with read value from the MMIO register.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT8
EFIAPI
MmioBitFieldAndThenOr8 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT8                     AndData,
  IN      UINT8                     OrData
  );

/**
  Reads a 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address. The 16-bit read value is
  returned. This function must guarantee that all MMIO read and write
  operations are serialized.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().

  @param  Address The MMIO register to read.

  @return The value read.

**/
UINT16
EFIAPI
MmioRead16 (
  IN      UINTN                     Address
  );

/**
  Writes a 16-bit MMIO register.

  Writes the 16-bit MMIO register specified by Address with the value specified
  by Value and returns Value. This function must guarantee that all MMIO read
  and write operations are serialized.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  Value   The value to write to the MMIO register.
  
  @return Value.

**/
UINT16
EFIAPI
MmioWrite16 (
  IN      UINTN                     Address,
  IN      UINT16                    Value
  );

/**
  Reads a 16-bit MMIO register, performs a bitwise OR, and writes the
  result back to the 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 16-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  OrData  The value to OR with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioOr16 (
  IN      UINTN                     Address,
  IN      UINT16                    OrData
  );

/**
  Reads a 16-bit MMIO register, performs a bitwise AND, and writes the result
  back to the 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 16-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioAnd16 (
  IN      UINTN                     Address,
  IN      UINT16                    AndData
  );

/**
  Reads a 16-bit MMIO register, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, performs a
  bitwise OR between the result of the AND operation and the value specified by
  OrData, and writes the result to the 16-bit MMIO register specified by
  Address. The value written to the MMIO register is returned. This function
  must guarantee that all MMIO read and write operations are serialized.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioAndThenOr16 (
  IN      UINTN                     Address,
  IN      UINT16                    AndData,
  IN      UINT16                    OrData
  );

/**
  Reads a bit field of a MMIO register.

  Reads the bit field in a 16-bit MMIO register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.

  @return The value read.

**/
UINT16
EFIAPI
MmioBitFieldRead16 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to a MMIO register.

  Writes Value to the bit field of the MMIO register. The bit field is
  specified by the StartBit and the EndBit. All other bits in the destination
  MMIO register are preserved. The new value of the 16-bit register is returned.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  Value     New value of the bit field.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioBitFieldWrite16 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    Value
  );

/**
  Reads a bit field in a 16-bit MMIO register, performs a bitwise OR, and
  writes the result back to the bit field in the 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 16-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized. Extra left bits in OrData
  are stripped.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  OrData    The value to OR with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioBitFieldOr16 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    OrData
  );

/**
  Reads a bit field in a 16-bit MMIO register, performs a bitwise AND, and
  writes the result back to the bit field in the 16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 16-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized. Extra left bits in AndData are
  stripped.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  AndData   The value to AND with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioBitFieldAnd16 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    AndData
  );

/**
  Reads a bit field in a 16-bit MMIO register, performs a bitwise AND followed
  by a bitwise OR, and writes the result back to the bit field in the
  16-bit MMIO register.

  Reads the 16-bit MMIO register specified by Address, performs a bitwise AND
  followed by a bitwise OR between the read result and the value
  specified by AndData, and writes the result to the 16-bit MMIO register
  specified by Address. The value written to the MMIO register is returned.
  This function must guarantee that all MMIO read and write operations are
  serialized. Extra left bits in both AndData and OrData are stripped.

  If 16-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 16-bit boundary, then ASSERT().
  If StartBit is greater than 15, then ASSERT().
  If EndBit is greater than 15, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..15.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..15.
  @param  AndData   The value to AND with read value from the MMIO register.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT16
EFIAPI
MmioBitFieldAndThenOr16 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT16                    AndData,
  IN      UINT16                    OrData
  );

/**
  Reads a 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address. The 32-bit read value is
  returned. This function must guarantee that all MMIO read and write
  operations are serialized.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().

  @param  Address The MMIO register to read.

  @return The value read.

**/
UINT32
EFIAPI
MmioRead32 (
  IN      UINTN                     Address
  );

/**
  Writes a 32-bit MMIO register.

  Writes the 32-bit MMIO register specified by Address with the value specified
  by Value and returns Value. This function must guarantee that all MMIO read
  and write operations are serialized.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  Value   The value to write to the MMIO register.
  
  @return Value.

**/
UINT32
EFIAPI
MmioWrite32 (
  IN      UINTN                     Address,
  IN      UINT32                    Value
  );

/**
  Reads a 32-bit MMIO register, performs a bitwise OR, and writes the
  result back to the 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 32-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  OrData  The value to OR with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioOr32 (
  IN      UINTN                     Address,
  IN      UINT32                    OrData
  );

/**
  Reads a 32-bit MMIO register, performs a bitwise AND, and writes the result
  back to the 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 32-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioAnd32 (
  IN      UINTN                     Address,
  IN      UINT32                    AndData
  );

/**
  Reads a 32-bit MMIO register, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, performs a
  bitwise OR between the result of the AND operation and the value specified by
  OrData, and writes the result to the 32-bit MMIO register specified by
  Address. The value written to the MMIO register is returned. This function
  must guarantee that all MMIO read and write operations are serialized.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioAndThenOr32 (
  IN      UINTN                     Address,
  IN      UINT32                    AndData,
  IN      UINT32                    OrData
  );

/**
  Reads a bit field of a MMIO register.

  Reads the bit field in a 32-bit MMIO register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.

  @return The value read.

**/
UINT32
EFIAPI
MmioBitFieldRead32 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to a MMIO register.

  Writes Value to the bit field of the MMIO register. The bit field is
  specified by the StartBit and the EndBit. All other bits in the destination
  MMIO register are preserved. The new value of the 32-bit register is returned.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  Value     New value of the bit field.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioBitFieldWrite32 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    Value
  );

/**
  Reads a bit field in a 32-bit MMIO register, performs a bitwise OR, and
  writes the result back to the bit field in the 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 32-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized. Extra left bits in OrData
  are stripped.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  OrData    The value to OR with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioBitFieldOr32 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    OrData
  );

/**
  Reads a bit field in a 32-bit MMIO register, performs a bitwise AND, and
  writes the result back to the bit field in the 32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 32-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized. Extra left bits in AndData are
  stripped.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  AndData   The value to AND with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioBitFieldAnd32 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    AndData
  );

/**
  Reads a bit field in a 32-bit MMIO register, performs a bitwise AND followed
  by a bitwise OR, and writes the result back to the bit field in the
  32-bit MMIO register.

  Reads the 32-bit MMIO register specified by Address, performs a bitwise AND
  followed by a bitwise OR between the read result and the value
  specified by AndData, and writes the result to the 32-bit MMIO register
  specified by Address. The value written to the MMIO register is returned.
  This function must guarantee that all MMIO read and write operations are
  serialized. Extra left bits in both AndData and OrData are stripped.

  If 32-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 32-bit boundary, then ASSERT().
  If StartBit is greater than 31, then ASSERT().
  If EndBit is greater than 31, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..31.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..31.
  @param  AndData   The value to AND with read value from the MMIO register.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT32
EFIAPI
MmioBitFieldAndThenOr32 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT32                    AndData,
  IN      UINT32                    OrData
  );

/**
  Reads a 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address. The 64-bit read value is
  returned. This function must guarantee that all MMIO read and write
  operations are serialized.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().

  @param  Address The MMIO register to read.

  @return The value read.

**/
UINT64
EFIAPI
MmioRead64 (
  IN      UINTN                     Address
  );

/**
  Writes a 64-bit MMIO register.

  Writes the 64-bit MMIO register specified by Address with the value specified
  by Value and returns Value. This function must guarantee that all MMIO read
  and write operations are serialized.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  Value   The value to write to the MMIO register.

**/
UINT64
EFIAPI
MmioWrite64 (
  IN      UINTN                     Address,
  IN      UINT64                    Value
  );

/**
  Reads a 64-bit MMIO register, performs a bitwise OR, and writes the
  result back to the 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 64-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  OrData  The value to OR with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioOr64 (
  IN      UINTN                     Address,
  IN      UINT64                    OrData
  );

/**
  Reads a 64-bit MMIO register, performs a bitwise AND, and writes the result
  back to the 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 64-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioAnd64 (
  IN      UINTN                     Address,
  IN      UINT64                    AndData
  );

/**
  Reads a 64-bit MMIO register, performs a bitwise AND followed by a bitwise 
  OR, and writes the result back to the 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, performs a
  bitwise OR between the result of the AND operation and the value specified by
  OrData, and writes the result to the 64-bit MMIO register specified by
  Address. The value written to the MMIO register is returned. This function
  must guarantee that all MMIO read and write operations are serialized.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().

  @param  Address The MMIO register to write.
  @param  AndData The value to AND with the read value from the MMIO register.
  @param  OrData  The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioAndThenOr64 (
  IN      UINTN                     Address,
  IN      UINT64                    AndData,
  IN      UINT64                    OrData
  );

/**
  Reads a bit field of a MMIO register.

  Reads the bit field in a 64-bit MMIO register. The bit field is specified by
  the StartBit and the EndBit. The value of the bit field is returned.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to read.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.

  @return The value read.

**/
UINT64
EFIAPI
MmioBitFieldRead64 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit
  );

/**
  Writes a bit field to a MMIO register.

  Writes Value to the bit field of the MMIO register. The bit field is
  specified by the StartBit and the EndBit. All other bits in the destination
  MMIO register are preserved. The new value of the 64-bit register is returned.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  Value     New value of the bit field.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioBitFieldWrite64 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    Value
  );

/**
  Reads a bit field in a 64-bit MMIO register, performs a bitwise OR, and
  writes the result back to the bit field in the 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise 
  OR between the read result and the value specified by OrData, and
  writes the result to the 64-bit MMIO register specified by Address. The value
  written to the MMIO register is returned. This function must guarantee that
  all MMIO read and write operations are serialized. Extra left bits in OrData
  are stripped.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  OrData    The value to OR with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioBitFieldOr64 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    OrData
  );

/**
  Reads a bit field in a 64-bit MMIO register, performs a bitwise AND, and
  writes the result back to the bit field in the 64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise AND
  between the read result and the value specified by AndData, and writes the
  result to the 64-bit MMIO register specified by Address. The value written to
  the MMIO register is returned. This function must guarantee that all MMIO
  read and write operations are serialized. Extra left bits in AndData are
  stripped.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  AndData   The value to AND with read value from the MMIO register.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioBitFieldAnd64 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    AndData
  );

/**
  Reads a bit field in a 64-bit MMIO register, performs a bitwise AND followed
  by a bitwise OR, and writes the result back to the bit field in the
  64-bit MMIO register.

  Reads the 64-bit MMIO register specified by Address, performs a bitwise AND
  followed by a bitwise OR between the read result and the value
  specified by AndData, and writes the result to the 64-bit MMIO register
  specified by Address. The value written to the MMIO register is returned.
  This function must guarantee that all MMIO read and write operations are
  serialized. Extra left bits in both AndData and OrData are stripped.

  If 64-bit MMIO register operations are not supported, then ASSERT().
  If Address is not aligned on a 64-bit boundary, then ASSERT().
  If StartBit is greater than 63, then ASSERT().
  If EndBit is greater than 63, then ASSERT().
  If EndBit is less than StartBit, then ASSERT().

  @param  Address   MMIO register to write.
  @param  StartBit  The ordinal of the least significant bit in the bit field.
                    Range 0..63.
  @param  EndBit    The ordinal of the most significant bit in the bit field.
                    Range 0..63.
  @param  AndData   The value to AND with read value from the MMIO register.
  @param  OrData    The value to OR with the result of the AND operation.

  @return The value written back to the MMIO register.

**/
UINT64
EFIAPI
MmioBitFieldAndThenOr64 (
  IN      UINTN                     Address,
  IN      UINTN                     StartBit,
  IN      UINTN                     EndBit,
  IN      UINT64                    AndData,
  IN      UINT64                    OrData
  );

/**
  Copy data from MMIO region to system memory by using 8-bit access.

  Copy data from MMIO region specified by starting address StartAddress 
  to system memory specified by Buffer by using 8-bit access. The total 
  number of byte to be copied is specified by Length. Buffer is returned.
  
  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().


  @param  StartAddress    Starting address for the MMIO region to be copied from.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer receiving the data read.

  @return Buffer

**/
UINT8 *
EFIAPI
MmioReadBuffer8 (
  IN  UINTN       StartAddress,
  IN  UINTN       Length,
  OUT UINT8       *Buffer
  );

/**
  Copy data from MMIO region to system memory by using 16-bit access.

  Copy data from MMIO region specified by starting address StartAddress 
  to system memory specified by Buffer by using 16-bit access. The total 
  number of byte to be copied is specified by Length. Buffer is returned.
  
  If StartAddress is not aligned on a 16-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

  If Length is not aligned on a 16-bit boundary, then ASSERT().
  If Buffer is not aligned on a 16-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied from.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer receiving the data read.

  @return Buffer

**/
UINT16 *
EFIAPI
MmioReadBuffer16 (
  IN  UINTN       StartAddress,
  IN  UINTN       Length,
  OUT UINT16      *Buffer
  );

/**
  Copy data from MMIO region to system memory by using 32-bit access.

  Copy data from MMIO region specified by starting address StartAddress 
  to system memory specified by Buffer by using 32-bit access. The total 
  number of byte to be copied is specified by Length. Buffer is returned.
  
  If StartAddress is not aligned on a 32-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

  If Length is not aligned on a 32-bit boundary, then ASSERT().
  If Buffer is not aligned on a 32-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied from.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer receiving the data read.

  @return Buffer

**/
UINT32 *
EFIAPI
MmioReadBuffer32 (
  IN  UINTN       StartAddress,
  IN  UINTN       Length,
  OUT UINT32      *Buffer
  );

/**
  Copy data from MMIO region to system memory by using 64-bit access.

  Copy data from MMIO region specified by starting address StartAddress 
  to system memory specified by Buffer by using 64-bit access. The total 
  number of byte to be copied is specified by Length. Buffer is returned.
  
  If StartAddress is not aligned on a 64-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

  If Length is not aligned on a 64-bit boundary, then ASSERT().
  If Buffer is not aligned on a 64-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied from.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer receiving the data read.

  @return Buffer

**/
UINT64 *
EFIAPI
MmioReadBuffer64 (
  IN  UINTN       StartAddress,
  IN  UINTN       Length,
  OUT UINT64      *Buffer
  );

/**
  Copy data from system memory to MMIO region by using 8-bit access.

  Copy data from system memory specified by Buffer to MMIO region specified 
  by starting address StartAddress by using 8-bit access. The total number 
  of byte to be copied is specified by Length. Buffer is returned.
  
  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS -Buffer + 1), then ASSERT().


  @param  StartAddress    Starting address for the MMIO region to be copied to.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer containing the data to write.

  @return Size in bytes of the copy.

**/
UINT8 *
EFIAPI
MmioWriteBuffer8 (
  IN  UINTN         StartAddress,
  IN  UINTN         Length,
  IN  CONST UINT8   *Buffer
  );

/**
  Copy data from system memory to MMIO region by using 16-bit access.

  Copy data from system memory specified by Buffer to MMIO region specified 
  by starting address StartAddress by using 16-bit access. The total number 
  of byte to be copied is specified by Length. Length is returned.
  
  If StartAddress is not aligned on a 16-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS -Buffer + 1), then ASSERT().

  If Length is not aligned on a 16-bit boundary, then ASSERT().

  If Buffer is not aligned on a 16-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied to.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer containing the data to write.

  @return Size in bytes of the copy.

**/
UINT16 *
EFIAPI
MmioWriteBuffer16 (
  IN  UINTN        StartAddress,
  IN  UINTN        Length,
  IN  CONST UINT16 *Buffer
  );

/**
  Copy data from system memory to MMIO region by using 32-bit access.

  Copy data from system memory specified by Buffer to MMIO region specified 
  by starting address StartAddress by using 32-bit access. The total number 
  of byte to be copied is specified by Length. Length is returned.
  
  If StartAddress is not aligned on a 32-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS -Buffer + 1), then ASSERT().

  If Length is not aligned on a 32-bit boundary, then ASSERT().

  If Buffer is not aligned on a 32-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied to.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer containing the data to write.

  @return Size in bytes of the copy.

**/
UINT32 *
EFIAPI
MmioWriteBuffer32 (
  IN  UINTN        StartAddress,
  IN  UINTN        Length,
  IN  CONST UINT32 *Buffer
  );

/**
  Copy data from system memory to MMIO region by using 64-bit access.

  Copy data from system memory specified by Buffer to MMIO region specified 
  by starting address StartAddress by using 64-bit access. The total number 
  of byte to be copied is specified by Length. Length is returned.
  
  If StartAddress is not aligned on a 64-bit boundary, then ASSERT().

  If Length is greater than (MAX_ADDRESS - StartAddress + 1), then ASSERT(). 
  If Length is greater than (MAX_ADDRESS -Buffer + 1), then ASSERT().

  If Length is not aligned on a 64-bit boundary, then ASSERT().

  If Buffer is not aligned on a 64-bit boundary, then ASSERT().

  @param  StartAddress    Starting address for the MMIO region to be copied to.
  @param  Length          The size, in bytes, of Buffer.
  @param  Buffer          Pointer to a system memory buffer containing the data to write.

  @return Size in bytes of the copy.

**/
UINT64 *
EFIAPI
MmioWriteBuffer64 (
  IN  UINTN        StartAddress,
  IN  UINTN        Length,
  IN  CONST UINT64 *Buffer
  );


#endif