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/** @file
I/O Library. This file has compiler specifics for ICC as there
is no ANSI C standard for doing IO.
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<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.
**/
#include "BaseIoLibIntrinsicInternal.h"
/**
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
)
{
UINT8 Data;
__asm {
mov dx, word ptr [Port]
in al, dx
mov Data, al
}
return Data;
}
/**
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
)
{
__asm {
mov al, byte ptr [Value]
mov dx, word ptr [Port]
out dx, al
}
return Value;
}
/**
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
)
{
UINT16 Data;
ASSERT ((Port & 1) == 0);
__asm {
mov dx, word ptr [Port]
in ax, dx
mov word ptr [Data], ax
}
return Data;
}
/**
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
)
{
ASSERT ((Port & 1) == 0);
__asm {
mov ax, word ptr [Value]
mov dx, word ptr [Port]
out dx, ax
}
return Value;
}
/**
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
)
{
UINT32 Data;
ASSERT ((Port & 3) == 0);
__asm {
mov dx, word ptr [Port]
in eax, dx
mov dword ptr [Data], eax
}
return Data;
}
/**
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
)
{
ASSERT ((Port & 3) == 0);
__asm {
mov eax, dword ptr [Value]
mov dx, word ptr [Port]
out dx, eax
}
return Value;
}