blob: a38f92e6a52904c87fe70f379a45326b8478be5d [file] [log] [blame]
#ifndef _ASM_IO_H
#define _ASM_IO_H
/*
* This file contains the definitions for the x86 IO instructions
* inb/inw/inl/outb/outw/outl and the "string versions" of the same
* (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
* versions of the single-IO instructions (inb_p/inw_p/..).
*
* This file is not meant to be obfuscating: it's just complicated
* to (a) handle it all in a way that makes gcc able to optimize it
* as well as possible and (b) trying to avoid writing the same thing
* over and over again with slight variations and possibly making a
* mistake somewhere.
*/
#ifdef SLOW_IO_BY_JUMPING
#define __SLOW_DOWN_IO __asm__ __volatile__("jmp 1f\n1:\tjmp 1f\n1:")
#else
#define __SLOW_DOWN_IO __asm__ __volatile__("outb %al,$0x80")
#endif
#ifdef REALLY_SLOW_IO
#define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
#else
#define SLOW_DOWN_IO __SLOW_DOWN_IO
#endif
/*
* Talk about misusing macros..
*/
#define __OUT1(s,x) \
static inline void __out##s(unsigned x value, unsigned short port) {
#define __OUT2(s,s1,s2) \
__asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
#define __OUT(s,s1,x) \
__OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); } \
__OUT1(s##c,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); } \
__OUT1(s##_p,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); SLOW_DOWN_IO; } \
__OUT1(s##c_p,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); SLOW_DOWN_IO; }
#define __IN1(s) \
static inline RETURN_TYPE __in##s(unsigned short port) { RETURN_TYPE _v;
#define __IN2(s,s1,s2) \
__asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
#define __IN(s,s1,i...) \
__IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); return _v; } \
__IN1(s##c) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); return _v; } \
__IN1(s##_p) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); SLOW_DOWN_IO; return _v; } \
__IN1(s##c_p) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); SLOW_DOWN_IO; return _v; }
#define __OUTS(s) \
static inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
{ __asm__ __volatile__ ("cld ; rep ; outs" #s \
: "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
#define RETURN_TYPE unsigned char
/* __IN(b,"b","0" (0)) */
__IN(b,"")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned short
/* __IN(w,"w","0" (0)) */
__IN(w,"")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned int
__IN(l,"")
#undef RETURN_TYPE
__OUT(b,"b",char)
__OUT(w,"w",short)
__OUT(l,,int)
__OUTS(b)
__OUTS(w)
__OUTS(l)
/*
* Note that due to the way __builtin_constant_p() works, you
* - can't use it inside a inline function (it will never be true)
* - you don't have to worry about side effects within the __builtin..
*/
#define outb(val,port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__outbc((val),(port)) : \
__outb((val),(port)))
#define inb(port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__inbc(port) : \
__inb(port))
#define outw(val,port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__outwc((val),(port)) : \
__outw((val),(port)))
#define inw(port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__inwc(port) : \
__inw(port))
#define outl(val,port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__outlc((val),(port)) : \
__outl((val),(port)))
#define inl(port) \
((__builtin_constant_p((port)) && (port) < 256) ? \
__inlc(port) : \
__inl(port))
#endif