1 files changed, 159 insertions, 0 deletions
diff --git a/include/asm-i386/io.h b/include/asm-i386/io.h
new file mode 100644
index 000000000..09c494ce8
--- /dev/null
+++ b/include/asm-i386/io.h
@@ -0,0 +1,159 @@
+#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.
+ */
+
+/*
+ * Thanks to James van Artsdalen for a better timing-fix than
+ * the two short jumps: using outb's to a nonexistent port seems
+ * to guarantee better timings even on fast machines.
+ *
+ * On the other hand, I'd like to be sure of a non-existent port:
+ * I feel a bit unsafe about using 0x80 (should be safe, though)
+ *
+ *		Linus
+ */
+
+#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) \
+extern 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), "i" (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), "i" (port)); SLOW_DOWN_IO; }
+
+#define __IN1(s) \
+extern inline unsigned int __in##s(unsigned short port) { unsigned int _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) : "i" (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) : "i" (port) ,##i ); SLOW_DOWN_IO; return _v; }
+
+#define __INS(s) \
+extern inline void ins##s(unsigned short port, void * addr, unsigned long count) \
+{ __asm__ __volatile__ ("cld ; rep ; ins" #s \
+: "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
+
+#define __OUTS(s) \
+extern 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)); }
+
+__IN(b,"b","0" (0))
+__IN(w,"w","0" (0))
+__IN(l,"")
+
+__OUT(b,"b",char)
+__OUT(w,"w",short)
+__OUT(l,,int)
+
+__INS(b)
+__INS(w)
+__INS(l)
+
+__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 outb_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__outbc_p((val),(port)) : \
+	__outb_p((val),(port)))
+
+#define inb_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__inbc_p(port) : \
+	__inb_p(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 outw_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__outwc_p((val),(port)) : \
+	__outw_p((val),(port)))
+
+#define inw_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__inwc_p(port) : \
+	__inw_p(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))
+
+#define outl_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__outlc_p((val),(port)) : \
+	__outl_p((val),(port)))
+
+#define inl_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+	__inlc_p(port) : \
+	__inl_p(port))
+
+#endif