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| author | Cédric Le Goater <clg@fr.ibm.com> | 2014-04-24 11:23:33 +0400 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-04-28 11:35:56 +0400 |
| commit | 98fd433aa6b02ba1612f9a9b73b8eb2f7e9d3419 (patch) | |
| tree | 0d6771a0ddc11bd0ce1d22eab04566896185fdc9 /arch/powerpc/boot/swab.h | |
| parent | b636031a7b0622ffdc5689ff36fb13669f00e160 (diff) | |
| download | linux-98fd433aa6b02ba1612f9a9b73b8eb2f7e9d3419.tar.xz | |
powerpc/boot: Define byteswapping routines for little endian
These are not the most efficient versions of swab but the wrapper does
not do much byte swapping. On a big endian cpu, these routines are
a no-op.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/boot/swab.h')
| -rw-r--r-- | arch/powerpc/boot/swab.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/powerpc/boot/swab.h b/arch/powerpc/boot/swab.h new file mode 100644 index 000000000000..d0e1431084ca --- /dev/null +++ b/arch/powerpc/boot/swab.h @@ -0,0 +1,29 @@ +#ifndef _PPC_BOOT_SWAB_H_ +#define _PPC_BOOT_SWAB_H_ + +static inline u16 swab16(u16 x) +{ + return ((x & (u16)0x00ffU) << 8) | + ((x & (u16)0xff00U) >> 8); +} + +static inline u32 swab32(u32 x) +{ + return ((x & (u32)0x000000ffUL) << 24) | + ((x & (u32)0x0000ff00UL) << 8) | + ((x & (u32)0x00ff0000UL) >> 8) | + ((x & (u32)0xff000000UL) >> 24); +} + +static inline u64 swab64(u64 x) +{ + return (u64)((x & (u64)0x00000000000000ffULL) << 56) | + (u64)((x & (u64)0x000000000000ff00ULL) << 40) | + (u64)((x & (u64)0x0000000000ff0000ULL) << 24) | + (u64)((x & (u64)0x00000000ff000000ULL) << 8) | + (u64)((x & (u64)0x000000ff00000000ULL) >> 8) | + (u64)((x & (u64)0x0000ff0000000000ULL) >> 24) | + (u64)((x & (u64)0x00ff000000000000ULL) >> 40) | + (u64)((x & (u64)0xff00000000000000ULL) >> 56); +} +#endif /* _PPC_BOOT_SWAB_H_ */ |