diff options
Diffstat (limited to 'arch/parisc/include/uapi/asm/swab.h')
| -rw-r--r-- | arch/parisc/include/uapi/asm/swab.h | 66 | 
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/parisc/include/uapi/asm/swab.h b/arch/parisc/include/uapi/asm/swab.h new file mode 100644 index 00000000000..e78403b129e --- /dev/null +++ b/arch/parisc/include/uapi/asm/swab.h @@ -0,0 +1,66 @@ +#ifndef _PARISC_SWAB_H +#define _PARISC_SWAB_H + +#include <linux/types.h> +#include <linux/compiler.h> + +#define __SWAB_64_THRU_32__ + +static inline __attribute_const__ __u16 __arch_swab16(__u16 x) +{ +	__asm__("dep %0, 15, 8, %0\n\t"		/* deposit 00ab -> 0bab */ +		"shd %%r0, %0, 8, %0"		/* shift 000000ab -> 00ba */ +		: "=r" (x) +		: "0" (x)); +	return x; +} +#define __arch_swab16 __arch_swab16 + +static inline __attribute_const__ __u32 __arch_swab24(__u32 x) +{ +	__asm__("shd %0, %0, 8, %0\n\t"		/* shift xabcxabc -> cxab */ +		"dep %0, 15, 8, %0\n\t"		/* deposit cxab -> cbab */ +		"shd %%r0, %0, 8, %0"		/* shift 0000cbab -> 0cba */ +		: "=r" (x) +		: "0" (x)); +	return x; +} + +static inline __attribute_const__ __u32 __arch_swab32(__u32 x) +{ +	unsigned int temp; +	__asm__("shd %0, %0, 16, %1\n\t"	/* shift abcdabcd -> cdab */ +		"dep %1, 15, 8, %1\n\t"		/* deposit cdab -> cbab */ +		"shd %0, %1, 8, %0"		/* shift abcdcbab -> dcba */ +		: "=r" (x), "=&r" (temp) +		: "0" (x)); +	return x; +} +#define __arch_swab32 __arch_swab32 + +#if BITS_PER_LONG > 32 +/* +** From "PA-RISC 2.0 Architecture", HP Professional Books. +** See Appendix I page 8 , "Endian Byte Swapping". +** +** Pretty cool algorithm: (* == zero'd bits) +**      PERMH   01234567 -> 67452301 into %0 +**      HSHL    67452301 -> 7*5*3*1* into %1 +**      HSHR    67452301 -> *6*4*2*0 into %0 +**      OR      %0 | %1  -> 76543210 into %0 (all done!) +*/ +static inline __attribute_const__ __u64 __arch_swab64(__u64 x) +{ +	__u64 temp; +	__asm__("permh,3210 %0, %0\n\t" +		"hshl %0, 8, %1\n\t" +		"hshr,u %0, 8, %0\n\t" +		"or %1, %0, %0" +		: "=r" (x), "=&r" (temp) +		: "0" (x)); +	return x; +} +#define __arch_swab64 __arch_swab64 +#endif /* BITS_PER_LONG > 32 */ + +#endif /* _PARISC_SWAB_H */  |