basekernel/kernel/ioports.h

102 lines
1.9 KiB
C

/*
Copyright (C) 2015-2019 The University of Notre Dame
This software is distributed under the GNU General Public License.
See the file LICENSE for details.
*/
#ifndef IOPORTS_H
#define IOPORTS_H
#include "kernel/types.h"
/*
These are C wrappers around the assembly instruction IN and OUT
to move data to and from I/O ports. These variants are historically
called inb/inw/inl outb/outw/outl for in/out of byte (8 bits),
word (16 bits), and long (32 bits) respectively.
Note that some devices requires the "slow" variants that do an
extra dummy I/O in order to give the device more time to respond.
*/
static inline uint8_t inb(int port)
{
uint8_t result;
asm("inb %w1, %b0": "=a"(result):"Nd"(port));
return result;
}
static inline uint16_t inw(int port)
{
uint16_t result;
asm("inw %w1, %w0": "=a"(result):"Nd"(port));
return result;
}
static inline uint16_t inl(int port)
{
uint32_t result;
asm("inl %w1, %0": "=a"(result):"Nd"(port));
return result;
}
static inline void outb(uint8_t value, int port)
{
asm("outb %b0, %w1": :"a"(value), "Nd"(port));
}
static inline void outw(uint16_t value, int port)
{
asm("outw %w0, %w1": :"a"(value), "Nd"(port));
}
static inline void outl(uint32_t value, int port)
{
asm("outl %0, %w1": :"a"(value), "Nd"(port));
}
static inline void iowait()
{
outb(0, 0x80);
}
static inline uint8_t inb_slow(int port)
{
uint8_t result = inb(port);
iowait();
return result;
}
static inline uint16_t inw_slow(int port)
{
uint16_t result = inw(port);
iowait();
return result;
}
static inline uint32_t inl_slow(int port)
{
uint32_t result = inl(port);
iowait();
return result;
}
static inline void outb_slow(uint8_t value, int port)
{
outb(value, port);
iowait();
}
static inline void outw_slow(uint16_t value, int port)
{
outw(value, port);
iowait();
}
static inline void outl_slow(uint32_t value, int port)
{
outl(value, port);
iowait();
}
#endif