mirror of
https://github.com/brain-hackers/u-boot-brain
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c1d1bfa583
UBIFS requires fls(), which is not defined for arm (and some other architectures) and this patch adds it. The implementation is taken from Linux and is generic. ffs() is also defined for those that miss it. Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
59 lines
1.1 KiB
C
59 lines
1.1 KiB
C
/*
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* bitops.h: Bit string operations on the m68k
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*/
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#ifndef _M68K_BITOPS_H
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#define _M68K_BITOPS_H
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#include <linux/config.h>
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#include <asm/byteorder.h>
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extern void set_bit(int nr, volatile void *addr);
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extern void clear_bit(int nr, volatile void *addr);
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extern void change_bit(int nr, volatile void *addr);
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extern int test_and_set_bit(int nr, volatile void *addr);
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extern int test_and_clear_bit(int nr, volatile void *addr);
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extern int test_and_change_bit(int nr, volatile void *addr);
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#ifdef __KERNEL__
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/*
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* ffs: find first bit set. This is defined the same way as
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* the libc and compiler builtin ffs routines, therefore
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* differs in spirit from the above ffz (man ffs).
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*/
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extern __inline__ int ffs(int x)
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{
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int r = 1;
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if (!x)
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return 0;
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if (!(x & 0xffff)) {
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x >>= 16;
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r += 16;
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}
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if (!(x & 0xff)) {
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x >>= 8;
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r += 8;
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}
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if (!(x & 0xf)) {
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x >>= 4;
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r += 4;
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}
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if (!(x & 3)) {
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x >>= 2;
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r += 2;
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}
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if (!(x & 1)) {
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x >>= 1;
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r += 1;
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}
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return r;
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}
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#define __ffs(x) (ffs(x) - 1)
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#define ffs
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#endif /* __KERNEL__ */
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#endif /* _M68K_BITOPS_H */
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