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- /*
- * include/asm-xtensa/bitops.h
- *
- * Atomic operations that C can't guarantee us.Useful for resource counting etc.
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2001 - 2007 Tensilica Inc.
- */
- #ifndef _XTENSA_BITOPS_H
- #define _XTENSA_BITOPS_H
- #ifdef __KERNEL__
- #ifndef _LINUX_BITOPS_H
- #error only <linux/bitops.h> can be included directly
- #endif
- #include <asm/processor.h>
- #include <asm/byteorder.h>
- #ifdef CONFIG_SMP
- # error SMP not supported on this architecture
- #endif
- #define smp_mb__before_clear_bit() barrier()
- #define smp_mb__after_clear_bit() barrier()
- #include <asm-generic/bitops/atomic.h>
- #include <asm-generic/bitops/non-atomic.h>
- #if XCHAL_HAVE_NSA
- static inline unsigned long __cntlz (unsigned long x)
- {
- int lz;
- asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
- return lz;
- }
- /*
- * ffz: Find first zero in word. Undefined if no zero exists.
- * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
- */
- static inline int ffz(unsigned long x)
- {
- return 31 - __cntlz(~x & -~x);
- }
- /*
- * __ffs: Find first bit set in word. Return 0 for bit 0
- */
- static inline int __ffs(unsigned long x)
- {
- return 31 - __cntlz(x & -x);
- }
- /*
- * ffs: Find first bit set in word. 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(unsigned long x)
- {
- return 32 - __cntlz(x & -x);
- }
- /*
- * fls: Find last (most-significant) bit set in word.
- * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
- */
- static inline int fls (unsigned int x)
- {
- return 32 - __cntlz(x);
- }
- /**
- * __fls - find last (most-significant) set bit in a long word
- * @word: the word to search
- *
- * Undefined if no set bit exists, so code should check against 0 first.
- */
- static inline unsigned long __fls(unsigned long word)
- {
- return 31 - __cntlz(word);
- }
- #else
- /* Use the generic implementation if we don't have the nsa/nsau instructions. */
- # include <asm-generic/bitops/ffs.h>
- # include <asm-generic/bitops/__ffs.h>
- # include <asm-generic/bitops/ffz.h>
- # include <asm-generic/bitops/fls.h>
- # include <asm-generic/bitops/__fls.h>
- #endif
- #include <asm-generic/bitops/fls64.h>
- #include <asm-generic/bitops/find.h>
- #include <asm-generic/bitops/le.h>
- #include <asm-generic/bitops/ext2-atomic-setbit.h>
- #include <asm-generic/bitops/hweight.h>
- #include <asm-generic/bitops/lock.h>
- #include <asm-generic/bitops/sched.h>
- #endif /* __KERNEL__ */
- #endif /* _XTENSA_BITOPS_H */
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