os/libc/ports.c

#include <stdint.h>

uint8_t port_byte_in(uint16_t port) {
  uint8_t result;
  asm("in %%dx, %%al":"=a"(result):"d"(port));
  return result;
}

void port_byte_out(uint16_t port,uint8_t data) {
  asm("out %%al, %%dx":: "a"(data),"d"(port));
}

uint16_t port_word_in(uint16_t port) {
  uint16_t result;
  asm("in %%dx, %%ax":"=a"(result):"d"(port));
  return result;
}

void port_word_out(uint16_t port,uint16_t data) {
  asm("out %%ax, %%dx":: "a" (data), "d" (port));
}

uint32_t port_long_in(uint16_t port) {
  uint32_t result;
  asm("inl %%dx, %%eax":"=a"(result):"d"(port));
  return result;
}

void port_long_out(uint16_t port,uint32_t data) {
  asm("outl %%eax, %%dx":: "a" (data), "d" (port));
}