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author | Stefan Roese <sr@denx.de> | 2007-08-21 16:33:33 +0200 |
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committer | Stefan Roese <sr@denx.de> | 2007-08-21 16:33:33 +0200 |
commit | 93f798346033a1f6d22090b47abad4be88243b04 (patch) | |
tree | 45b4d2a887a89572015de3234b04b419bfc11b44 /include/asm-m68k/bitops.h | |
parent | 3ad63878737a5a2b1e60825bf0a7d601d7a695e7 (diff) | |
parent | 3e66c078003607a7d1d214c15a5f262bc1b4032f (diff) | |
download | u-boot-imx-93f798346033a1f6d22090b47abad4be88243b04.zip u-boot-imx-93f798346033a1f6d22090b47abad4be88243b04.tar.gz u-boot-imx-93f798346033a1f6d22090b47abad4be88243b04.tar.bz2 |
Merge with /home/stefan/git/u-boot/u-boot-ppc4xx
Diffstat (limited to 'include/asm-m68k/bitops.h')
-rw-r--r-- | include/asm-m68k/bitops.h | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/include/asm-m68k/bitops.h b/include/asm-m68k/bitops.h index 3283714..0f9e8ab 100644 --- a/include/asm-m68k/bitops.h +++ b/include/asm-m68k/bitops.h @@ -15,4 +15,43 @@ extern int test_and_set_bit(int nr, volatile void *addr); extern int test_and_clear_bit(int nr, volatile void *addr); extern int test_and_change_bit(int nr, volatile void *addr); +#ifdef __KERNEL__ + +/* + * ffs: find first bit set. This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +extern __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; +} +#define __ffs(x) (ffs(x) - 1) + +#endif /* __KERNEL__ */ + #endif /* _M68K_BITOPS_H */ |