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author | Thomas Chou <thomas@wytron.com.tw> | 2010-03-20 07:05:46 +0800 |
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committer | Scott McNutt <smcnutt@psyent.com> | 2010-04-02 12:28:40 -0400 |
commit | 3bef253f0802c6292b8e2acc0089894019e99e62 (patch) | |
tree | 4117b2da164130ffc4ee38b35f472e853142427c /include/asm-nios2/bitops/ffs.h | |
parent | d8b73dffa9866d6de3c05c8a2d07ecd4bc0d5d7e (diff) | |
download | u-boot-imx-3bef253f0802c6292b8e2acc0089894019e99e62.zip u-boot-imx-3bef253f0802c6292b8e2acc0089894019e99e62.tar.gz u-boot-imx-3bef253f0802c6292b8e2acc0089894019e99e62.tar.bz2 |
nios2: use bitops from linux-2.6 asm-generic
These are needed to use ubi/ubifs.
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
Diffstat (limited to 'include/asm-nios2/bitops/ffs.h')
-rw-r--r-- | include/asm-nios2/bitops/ffs.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/include/asm-nios2/bitops/ffs.h b/include/asm-nios2/bitops/ffs.h new file mode 100644 index 0000000..fbbb43a --- /dev/null +++ b/include/asm-nios2/bitops/ffs.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FFS_H_ +#define _ASM_GENERIC_BITOPS_FFS_H_ + +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static inline int ffs(int x) +{ + int r = 1; + + if (!x) + return 0; + if (!(x & 0xffff)) { + x >>= 16; + r += 16; + } + if (!(x & 0xff)) { + x >>= 8; + r += 8; + } + if (!(x & 0xf)) { + x >>= 4; + r += 4; + } + if (!(x & 3)) { + x >>= 2; + r += 2; + } + if (!(x & 1)) { + x >>= 1; + r += 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */ |