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Diffstat (limited to 'arch/tile/include/asm/bitops_32.h')
-rw-r--r-- | arch/tile/include/asm/bitops_32.h | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/arch/tile/include/asm/bitops_32.h b/arch/tile/include/asm/bitops_32.h new file mode 100644 index 000000000000..7a93c001ac19 --- /dev/null +++ b/arch/tile/include/asm/bitops_32.h @@ -0,0 +1,132 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#ifndef _ASM_TILE_BITOPS_32_H +#define _ASM_TILE_BITOPS_32_H + +#include <linux/compiler.h> +#include <asm/atomic.h> +#include <asm/system.h> + +/* Tile-specific routines to support <asm/bitops.h>. */ +unsigned long _atomic_or(volatile unsigned long *p, unsigned long mask); +unsigned long _atomic_andn(volatile unsigned long *p, unsigned long mask); +unsigned long _atomic_xor(volatile unsigned long *p, unsigned long mask); + +/** + * set_bit - Atomically set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + * + * This function is atomic and may not be reordered. + * See __set_bit() if you do not require the atomic guarantees. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ +static inline void set_bit(unsigned nr, volatile unsigned long *addr) +{ + _atomic_or(addr + BIT_WORD(nr), BIT_MASK(nr)); +} + +/** + * clear_bit - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * clear_bit() is atomic and may not be reordered. + * See __clear_bit() if you do not require the atomic guarantees. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + * + * clear_bit() may not contain a memory barrier, so if it is used for + * locking purposes, you should call smp_mb__before_clear_bit() and/or + * smp_mb__after_clear_bit() to ensure changes are visible on other cpus. + */ +static inline void clear_bit(unsigned nr, volatile unsigned long *addr) +{ + _atomic_andn(addr + BIT_WORD(nr), BIT_MASK(nr)); +} + +/** + * change_bit - Toggle a bit in memory + * @nr: Bit to change + * @addr: Address to start counting from + * + * change_bit() is atomic and may not be reordered. + * See __change_bit() if you do not require the atomic guarantees. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ +static inline void change_bit(unsigned nr, volatile unsigned long *addr) +{ + _atomic_xor(addr + BIT_WORD(nr), BIT_MASK(nr)); +} + +/** + * test_and_set_bit - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. + */ +static inline int test_and_set_bit(unsigned nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + addr += BIT_WORD(nr); + smp_mb(); /* barrier for proper semantics */ + return (_atomic_or(addr, mask) & mask) != 0; +} + +/** + * test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to clear + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. + */ +static inline int test_and_clear_bit(unsigned nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + addr += BIT_WORD(nr); + smp_mb(); /* barrier for proper semantics */ + return (_atomic_andn(addr, mask) & mask) != 0; +} + +/** + * test_and_change_bit - Change a bit and return its old value + * @nr: Bit to change + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. + */ +static inline int test_and_change_bit(unsigned nr, + volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + addr += BIT_WORD(nr); + smp_mb(); /* barrier for proper semantics */ + return (_atomic_xor(addr, mask) & mask) != 0; +} + +/* See discussion at smp_mb__before_atomic_dec() in <asm/atomic.h>. */ +#define smp_mb__before_clear_bit() smp_mb() +#define smp_mb__after_clear_bit() do {} while (0) + +#include <asm-generic/bitops/non-atomic.h> +#include <asm-generic/bitops/ext2-atomic.h> + +#endif /* _ASM_TILE_BITOPS_32_H */ |