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libhermit/arch/x86_64/loader/include/io.h
2018-04-22 16:47:28 +00:00

100 lines
3.4 KiB
C

/*
* Copyright (c) 2010, Stefan Lankes, RWTH Aachen University
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __IO_H__
#define __IO_H__
#ifdef __cplusplus
extern "C" {
#endif
/** @brief Read a byte from an IO port
*
* @param _port The port you want to read from
* @return The value which reads out from this port
*/
inline static unsigned char inportb(unsigned short _port) {
unsigned char rv;
asm volatile("inb %1, %0":"=a"(rv):"dN"(_port));
return rv;
}
/** @brief Read a word (2 byte) from an IO port
*
* @param _port The port you want to read from
* @return The value which reads out from this port
*/
inline static unsigned short inportw(unsigned short _port) {
unsigned short rv;
asm volatile("inw %1, %0":"=a"(rv):"dN"(_port));
return rv;
}
/** @brief Read a double word (4 byte) from an IO port
*
* @param _port The port you want to read from
* @return The value which reads out from this port
*/
inline static unsigned int inportl(unsigned short _port) {
unsigned int rv;
asm volatile("inl %1, %0":"=a"(rv):"dN"(_port));
return rv;
}
/** @brief Write a byte to an IO port
*
* @param _port The port you want to write to
* @param _data the 1 byte value you want to write
*/
inline static void outportb(unsigned short _port, unsigned char _data) {
asm volatile("outb %1, %0"::"dN"(_port), "a"(_data));
}
/** @brief Write a word (2 bytes) to an IO port
*
* @param _port The port you want to write to
* @param _data the 2 byte value you want to write
*/
inline static void outportw(unsigned short _port, unsigned short _data) {
asm volatile("outw %1, %0"::"dN"(_port), "a"(_data));
}
/** @brief Write a double word (4 bytes) to an IO port
*
* @param _port The port you want to write to
* @param _data the 4 byte value you want to write
*/
inline static void outportl(unsigned short _port, unsigned int _data)
{
asm volatile("outl %1, %0"::"dN"(_port), "a"(_data));
}
#ifdef __cplusplus
}
#endif
#endif