diff options
Diffstat (limited to 'arch/x86/include/asm/swab.h')
| -rw-r--r-- | arch/x86/include/asm/swab.h | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/x86/include/asm/swab.h b/arch/x86/include/asm/swab.h new file mode 100644 index 000000000000..306d4178ffc9 --- /dev/null +++ b/arch/x86/include/asm/swab.h @@ -0,0 +1,61 @@ +#ifndef _ASM_X86_SWAB_H +#define _ASM_X86_SWAB_H + +#include <asm/types.h> +#include <linux/compiler.h> + +static inline __attribute_const__ __u32 __arch_swab32(__u32 val) +{ +#ifdef __i386__ +# ifdef CONFIG_X86_BSWAP + asm("bswap %0" : "=r" (val) : "0" (val)); +# else + asm("xchgb %b0,%h0\n\t" /* swap lower bytes */ + "rorl $16,%0\n\t" /* swap words */ + "xchgb %b0,%h0" /* swap higher bytes */ + : "=q" (val) + : "0" (val)); +# endif + +#else /* __i386__ */ + asm("bswapl %0" + : "=r" (val) + : "0" (val)); +#endif + return val; +} +#define __arch_swab32 __arch_swab32 + +static inline __attribute_const__ __u64 __arch_swab64(__u64 val) +{ +#ifdef __i386__ + union { + struct { + __u32 a; + __u32 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; +#else /* __i386__ */ + asm("bswapq %0" + : "=r" (val) + : "0" (val)); + return val; +#endif +} +#define __arch_swab64 __arch_swab64 + +#endif /* _ASM_X86_SWAB_H */ |