kernel/portio.h

   1 /*
   2  *    Copyright (c) 2008 Joshua Phillips. All rights reserved.
   3  *
   4  *  Redistribution and use in source and binary forms, with or without
   5  *  modification, are permitted provided that the following conditions are
   6  *  met:
   7  *
   8  *    1. Redistributions of source code must retain the above copyright
   9  *       notice, this list of conditions and the following disclaimer.
  10  *    2. Redistributions in binary form must reproduce the above copyright
  11  *       notice, this list of conditions and the following disclaimer in
  12  *       the documentation and/or other materials provided with the
  13  *       distribution.
  14  *
  15  *  THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
  16  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  18  *  DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  19  *  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  21  *  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  23  *  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  *  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  25  *  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #ifndef PORTIO_H
  29 #define PORTIO_H
  30
  31 #include "stddef.h"
  32
  33 static inline void outb(int port, unsigned char value)
  34 {
  35         asm volatile ("outb %%al,%%dx" :: "a" (value), "d" (port));
  36 }
  37
  38 static inline void outw(int port, unsigned short value)
  39 {
  40         asm volatile ("outw %%ax,%%dx" :: "a" (value), "d" (port));
  41 }
  42
  43 static inline void outl(int port, unsigned long value)
  44 {
  45         asm volatile ("outl %%eax,%%dx" :: "a" (value), "d" (port));
  46 }
  47
  48 static inline unsigned char inb(int port)
  49 {
  50         unsigned char value;
  51         asm volatile ("inb %%dx,%%al" : "=a" (value) : "d" (port));
  52         return value;
  53 }
  54
  55 static inline unsigned short inw(int port)
  56 {
  57         unsigned short value;
  58         asm volatile ("inw %%dx,%%ax" : "=a" (value) : "d" (port));
  59         return value;
  60 }
  61
  62 static inline unsigned long inl(int port)
  63 {
  64         unsigned long value;
  65         asm volatile ("inl %%dx,%%eax" : "=a" (value) : "d" (port));
  66         return value;
  67 }
  68
  69 #endif
  70