diff options
Diffstat (limited to 'include/asm-i386/byteorder.h')
-rw-r--r-- | include/asm-i386/byteorder.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/include/asm-i386/byteorder.h b/include/asm-i386/byteorder.h new file mode 100644 index 000000000000..a0d73f48d5be --- /dev/null +++ b/include/asm-i386/byteorder.h @@ -0,0 +1,59 @@ +#ifndef _I386_BYTEORDER_H +#define _I386_BYTEORDER_H + +#include <asm/types.h> +#include <linux/compiler.h> + +#ifdef __GNUC__ + +/* For avoiding bswap on i386 */ +#ifdef __KERNEL__ +#include <linux/config.h> +#endif + +static __inline__ __attribute_const__ __u32 ___arch__swab32(__u32 x) +{ +#ifdef CONFIG_X86_BSWAP + __asm__("bswap %0" : "=r" (x) : "0" (x)); +#else + __asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */ + "rorl $16,%0\n\t" /* swap words */ + "xchgb %b0,%h0" /* swap higher bytes */ + :"=q" (x) + : "0" (x)); +#endif + return x; +} + +static __inline__ __attribute_const__ __u64 ___arch__swab64(__u64 val) +{ + union { + struct { __u32 a,b; } s; + __u64 u; + } v; + v.u = val; +#ifdef CONFIG_X86_BSWAP + asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1" + : "=r" (v.s.a), "=r" (v.s.b) + : "0" (v.s.a), "1" (v.s.b)); +#else + v.s.a = ___arch__swab32(v.s.a); + v.s.b = ___arch__swab32(v.s.b); + asm("xchgl %0,%1" : "=r" (v.s.a), "=r" (v.s.b) : "0" (v.s.a), "1" (v.s.b)); +#endif + return v.u; +} + +/* Do not define swab16. Gcc is smart enough to recognize "C" version and + convert it into rotation or exhange. */ + +#define __arch__swab64(x) ___arch__swab64(x) +#define __arch__swab32(x) ___arch__swab32(x) + +#define __BYTEORDER_HAS_U64__ + +#endif /* __GNUC__ */ + +#include <linux/byteorder/little_endian.h> + +#endif /* _I386_BYTEORDER_H */ |