audk/OvmfPkg/QemuVideoDxe/UnalignedIoInternal.h

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/** @file
Unaligned port I/O, with implementations for various x86 compilers and a
dummy for platforms which do not support unaligned port I/O.
Copyright (c) 2017, Phil Dennis-Jordan.<BR>
This program and the accompanying materials are licensed and made available
under the terms and conditions of the BSD License which accompanies this
distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#ifndef _UNALIGNED_IO_INTERNAL_H_
#define _UNALIGNED_IO_INTERNAL_H_
/**
Performs a 32-bit write to the specified, possibly unaligned I/O-type address.
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 unaligned I/O port operations are not supported, then ASSERT().
@param[in] Port I/O port address
@param[in] Value 32-bit word to write
@return The value written to the I/O port.
**/
UINT32
UnalignedIoWrite32 (
IN UINTN Port,
IN UINT32 Value
);
/**
Reads a 32-bit word from the specified, possibly unaligned I/O-type address.
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 unaligned I/O port operations are not supported, then ASSERT().
@param[in] Port The I/O port to read.
@return The value read.
**/
UINT32
UnalignedIoRead32 (
IN UINTN Port
);
#endif