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Diffstat (limited to 'arch/parisc/include/asm/swab.h')
-rw-r--r-- | arch/parisc/include/asm/swab.h | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/swab.h b/arch/parisc/include/asm/swab.h new file mode 100644 index 00000000000..3ff16c5a335 --- /dev/null +++ b/arch/parisc/include/asm/swab.h @@ -0,0 +1,66 @@ +#ifndef _PARISC_SWAB_H +#define _PARISC_SWAB_H + +#include <asm/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 */ |