mirror of https://github.com/acidanthera/audk.git
253 lines
6.4 KiB
C
253 lines
6.4 KiB
C
/** @file
|
|
Unaligned access functions of BaseLib for ARM.
|
|
|
|
volatile was added to work around optimization issues.
|
|
|
|
Copyright (c) 2006 - 2009, Intel Corporation<BR>
|
|
Portions Copyright (c) 2008-2009 Apple Inc.<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.
|
|
|
|
**/
|
|
|
|
#include "BaseLibInternals.h"
|
|
|
|
/**
|
|
Reads a 16-bit value from memory that may be unaligned.
|
|
|
|
This function returns the 16-bit value pointed to by Buffer. The function
|
|
guarantees that the read operation does not produce an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 16-bit value that may be unaligned.
|
|
|
|
@return The 16-bit value read from Buffer.
|
|
|
|
**/
|
|
UINT16
|
|
EFIAPI
|
|
ReadUnaligned16 (
|
|
IN CONST UINT16 *Buffer
|
|
)
|
|
{
|
|
volatile UINT8 LowerByte;
|
|
volatile UINT8 HigherByte;
|
|
|
|
ASSERT (Buffer != NULL);
|
|
|
|
LowerByte = ((UINT8*)Buffer)[0];
|
|
HigherByte = ((UINT8*)Buffer)[1];
|
|
|
|
return (UINT16)(LowerByte | (HigherByte << 8));
|
|
}
|
|
|
|
/**
|
|
Writes a 16-bit value to memory that may be unaligned.
|
|
|
|
This function writes the 16-bit value specified by Value to Buffer. Value is
|
|
returned. The function guarantees that the write operation does not produce
|
|
an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 16-bit value that may be unaligned.
|
|
@param Value 16-bit value to write to Buffer.
|
|
|
|
@return The 16-bit value to write to Buffer.
|
|
|
|
**/
|
|
UINT16
|
|
EFIAPI
|
|
WriteUnaligned16 (
|
|
OUT UINT16 *Buffer,
|
|
IN UINT16 Value
|
|
)
|
|
{
|
|
ASSERT (Buffer != NULL);
|
|
|
|
((volatile UINT8*)Buffer)[0] = (UINT8)Value;
|
|
((volatile UINT8*)Buffer)[1] = (UINT8)(Value >> 8);
|
|
|
|
return Value;
|
|
}
|
|
|
|
/**
|
|
Reads a 24-bit value from memory that may be unaligned.
|
|
|
|
This function returns the 24-bit value pointed to by Buffer. The function
|
|
guarantees that the read operation does not produce an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 24-bit value that may be unaligned.
|
|
|
|
@return The 24-bit value read from Buffer.
|
|
|
|
**/
|
|
UINT32
|
|
EFIAPI
|
|
ReadUnaligned24 (
|
|
IN CONST UINT32 *Buffer
|
|
)
|
|
{
|
|
ASSERT (Buffer != NULL);
|
|
|
|
return (UINT32)(
|
|
ReadUnaligned16 ((UINT16*)Buffer) |
|
|
(((UINT8*)Buffer)[2] << 16)
|
|
);
|
|
}
|
|
|
|
/**
|
|
Writes a 24-bit value to memory that may be unaligned.
|
|
|
|
This function writes the 24-bit value specified by Value to Buffer. Value is
|
|
returned. The function guarantees that the write operation does not produce
|
|
an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 24-bit value that may be unaligned.
|
|
@param Value 24-bit value to write to Buffer.
|
|
|
|
@return The 24-bit value to write to Buffer.
|
|
|
|
**/
|
|
UINT32
|
|
EFIAPI
|
|
WriteUnaligned24 (
|
|
OUT UINT32 *Buffer,
|
|
IN UINT32 Value
|
|
)
|
|
{
|
|
ASSERT (Buffer != NULL);
|
|
|
|
WriteUnaligned16 ((UINT16*)Buffer, (UINT16)Value);
|
|
*(UINT8*)((UINT16*)Buffer + 1) = (UINT8)(Value >> 16);
|
|
return Value;
|
|
}
|
|
|
|
/**
|
|
Reads a 32-bit value from memory that may be unaligned.
|
|
|
|
This function returns the 32-bit value pointed to by Buffer. The function
|
|
guarantees that the read operation does not produce an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 32-bit value that may be unaligned.
|
|
|
|
@return The 32-bit value read from Buffer.
|
|
|
|
**/
|
|
UINT32
|
|
EFIAPI
|
|
ReadUnaligned32 (
|
|
IN CONST UINT32 *Buffer
|
|
)
|
|
{
|
|
UINT16 LowerBytes;
|
|
UINT16 HigherBytes;
|
|
|
|
ASSERT (Buffer != NULL);
|
|
|
|
LowerBytes = ReadUnaligned16 ((UINT16*) Buffer);
|
|
HigherBytes = ReadUnaligned16 ((UINT16*) Buffer + 1);
|
|
|
|
return (UINT32) (LowerBytes | (HigherBytes << 16));
|
|
}
|
|
|
|
/**
|
|
Writes a 32-bit value to memory that may be unaligned.
|
|
|
|
This function writes the 32-bit value specified by Value to Buffer. Value is
|
|
returned. The function guarantees that the write operation does not produce
|
|
an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 32-bit value that may be unaligned.
|
|
@param Value 32-bit value to write to Buffer.
|
|
|
|
@return The 32-bit value to write to Buffer.
|
|
|
|
**/
|
|
UINT32
|
|
EFIAPI
|
|
WriteUnaligned32 (
|
|
OUT UINT32 *Buffer,
|
|
IN UINT32 Value
|
|
)
|
|
{
|
|
ASSERT (Buffer != NULL);
|
|
|
|
WriteUnaligned16 ((UINT16*)Buffer, (UINT16)Value);
|
|
WriteUnaligned16 ((UINT16*)Buffer + 1, (UINT16)(Value >> 16));
|
|
return Value;
|
|
}
|
|
|
|
/**
|
|
Reads a 64-bit value from memory that may be unaligned.
|
|
|
|
This function returns the 64-bit value pointed to by Buffer. The function
|
|
guarantees that the read operation does not produce an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 64-bit value that may be unaligned.
|
|
|
|
@return The 64-bit value read from Buffer.
|
|
|
|
**/
|
|
UINT64
|
|
EFIAPI
|
|
ReadUnaligned64 (
|
|
IN CONST UINT64 *Buffer
|
|
)
|
|
{
|
|
UINT32 LowerBytes;
|
|
UINT32 HigherBytes;
|
|
|
|
ASSERT (Buffer != NULL);
|
|
|
|
LowerBytes = ReadUnaligned32 ((UINT32*) Buffer);
|
|
HigherBytes = ReadUnaligned32 ((UINT32*) Buffer + 1);
|
|
|
|
return (UINT64) (LowerBytes | LShiftU64 (HigherBytes, 32));
|
|
}
|
|
|
|
/**
|
|
Writes a 64-bit value to memory that may be unaligned.
|
|
|
|
This function writes the 64-bit value specified by Value to Buffer. Value is
|
|
returned. The function guarantees that the write operation does not produce
|
|
an alignment fault.
|
|
|
|
If the Buffer is NULL, then ASSERT().
|
|
|
|
@param Buffer Pointer to a 64-bit value that may be unaligned.
|
|
@param Value 64-bit value to write to Buffer.
|
|
|
|
@return The 64-bit value to write to Buffer.
|
|
|
|
**/
|
|
UINT64
|
|
EFIAPI
|
|
WriteUnaligned64 (
|
|
OUT UINT64 *Buffer,
|
|
IN UINT64 Value
|
|
)
|
|
{
|
|
ASSERT (Buffer != NULL);
|
|
|
|
WriteUnaligned32 ((UINT32*)Buffer, (UINT32)Value);
|
|
WriteUnaligned32 ((UINT32*)Buffer + 1, (UINT32)RShiftU64 (Value, 32));
|
|
return Value;
|
|
}
|