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| author | Greg Watson <jarrah@users.sourceforge.net> | 2004-03-13 03:37:11 +0000 |
|---|---|---|
| committer | Greg Watson <jarrah@users.sourceforge.net> | 2004-03-13 03:37:11 +0000 |
| commit | 4f566ca1c0cc9e3b2984fe684e7df07d5dc73c53 (patch) | |
| tree | 87ba326ef87d0540b22307fe09569fd32d905ea4 /src/include/swab.h | |
| parent | 1624782bbe44018a1784cf78839bc4ec95802fdf (diff) | |
| download | coreboot-4f566ca1c0cc9e3b2984fe684e7df07d5dc73c53.tar.gz coreboot-4f566ca1c0cc9e3b2984fe684e7df07d5dc73c53.tar.bz2 coreboot-4f566ca1c0cc9e3b2984fe684e7df07d5dc73c53.zip | |
byte swapping
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1406 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Diffstat (limited to 'src/include/swab.h')
| -rw-r--r-- | src/include/swab.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/include/swab.h b/src/include/swab.h new file mode 100644 index 000000000000..3a166863ec6e --- /dev/null +++ b/src/include/swab.h @@ -0,0 +1,33 @@ +#ifndef _SWAB_H +#define _SWAB_H + +/* + * linux/byteorder/swab.h + * Byte-swapping, independently from CPU endianness + * swabXX[ps]?(foo) + * + * Francois-Rene Rideau <fare@tunes.org> 19971205 + * separated swab functions from cpu_to_XX, + * to clean up support for bizarre-endian architectures. + * + * See asm-i386/byteorder.h and suches for examples of how to provide + * architecture-dependent optimized versions + * + */ + +/* casts are necessary for constants, because we never know how for sure + * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way. + */ +#define swab16(x) \ + ((unsigned short)( \ + (((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \ + (((unsigned short)(x) & (unsigned short)0xff00U) >> 8) )) + +#define swab32(x) \ + ((unsigned int)( \ + (((unsigned int)(x) & (unsigned int)0x000000ffUL) << 24) | \ + (((unsigned int)(x) & (unsigned int)0x0000ff00UL) << 8) | \ + (((unsigned int)(x) & (unsigned int)0x00ff0000UL) >> 8) | \ + (((unsigned int)(x) & (unsigned int)0xff000000UL) >> 24) )) + +#endif /* _SWAB_H */ |