diff options
Diffstat (limited to 'arch/xtensa/include/asm/bitops.h')
-rw-r--r-- | arch/xtensa/include/asm/bitops.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/bitops.h b/arch/xtensa/include/asm/bitops.h new file mode 100644 index 00000000..5270197d --- /dev/null +++ b/arch/xtensa/include/asm/bitops.h @@ -0,0 +1,118 @@ +/* + * 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 */ |