diff options
Diffstat (limited to 'include/asm-mips/bitops.h')
| -rw-r--r-- | include/asm-mips/bitops.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/include/asm-mips/bitops.h b/include/asm-mips/bitops.h index 899357a72ac4..ec75ce4cdb8c 100644 --- a/include/asm-mips/bitops.h +++ b/include/asm-mips/bitops.h @@ -9,6 +9,10 @@ #ifndef _ASM_BITOPS_H #define _ASM_BITOPS_H +#ifndef _LINUX_BITOPS_H +#error only <linux/bitops.h> can be included directly +#endif + #include <linux/compiler.h> #include <linux/irqflags.h> #include <linux/types.h> @@ -172,6 +176,20 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr) } /* + * clear_bit_unlock - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * clear_bit() is atomic and implies release semantics before the memory + * operation. It can be used for an unlock. + */ +static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) +{ + smp_mb__before_clear_bit(); + clear_bit(nr, addr); +} + +/* * change_bit - Toggle a bit in memory * @nr: Bit to change * @addr: Address to start counting from @@ -240,6 +258,8 @@ static inline int test_and_set_bit(unsigned long nr, unsigned short bit = nr & SZLONG_MASK; unsigned long res; + smp_llsc_mb(); + if (cpu_has_llsc && R10000_LLSC_WAR) { unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); unsigned long temp; @@ -295,6 +315,73 @@ static inline int test_and_set_bit(unsigned long nr, } /* + * test_and_set_bit_lock - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and implies acquire ordering semantics + * after the memory operation. + */ +static inline int test_and_set_bit_lock(unsigned long nr, + volatile unsigned long *addr) +{ + unsigned short bit = nr & SZLONG_MASK; + unsigned long res; + + if (cpu_has_llsc && R10000_LLSC_WAR) { + unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); + unsigned long temp; + + __asm__ __volatile__( + " .set mips3 \n" + "1: " __LL "%0, %1 # test_and_set_bit \n" + " or %2, %0, %3 \n" + " " __SC "%2, %1 \n" + " beqzl %2, 1b \n" + " and %2, %0, %3 \n" + " .set mips0 \n" + : "=&r" (temp), "=m" (*m), "=&r" (res) + : "r" (1UL << bit), "m" (*m) + : "memory"); + } else if (cpu_has_llsc) { + unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); + unsigned long temp; + + __asm__ __volatile__( + " .set push \n" + " .set noreorder \n" + " .set mips3 \n" + "1: " __LL "%0, %1 # test_and_set_bit \n" + " or %2, %0, %3 \n" + " " __SC "%2, %1 \n" + " beqz %2, 2f \n" + " and %2, %0, %3 \n" + " .subsection 2 \n" + "2: b 1b \n" + " nop \n" + " .previous \n" + " .set pop \n" + : "=&r" (temp), "=m" (*m), "=&r" (res) + : "r" (1UL << bit), "m" (*m) + : "memory"); + } else { + volatile unsigned long *a = addr; + unsigned long mask; + unsigned long flags; + + a += nr >> SZLONG_LOG; + mask = 1UL << bit; + raw_local_irq_save(flags); + res = (mask & *a); + *a |= mask; + raw_local_irq_restore(flags); + } + + smp_llsc_mb(); + + return res != 0; +} +/* * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from @@ -308,6 +395,8 @@ static inline int test_and_clear_bit(unsigned long nr, unsigned short bit = nr & SZLONG_MASK; unsigned long res; + smp_llsc_mb(); + if (cpu_has_llsc && R10000_LLSC_WAR) { unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); unsigned long temp; @@ -396,6 +485,8 @@ static inline int test_and_change_bit(unsigned long nr, unsigned short bit = nr & SZLONG_MASK; unsigned long res; + smp_llsc_mb(); + if (cpu_has_llsc && R10000_LLSC_WAR) { unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); unsigned long temp; @@ -453,6 +544,21 @@ static inline int test_and_change_bit(unsigned long nr, #include <asm-generic/bitops/non-atomic.h> /* + * __clear_bit_unlock - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * __clear_bit() is non-atomic and implies release semantics before the memory + * operation. It can be used for an unlock if no other CPUs can concurrently + * modify other bits in the word. + */ +static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) +{ + smp_mb(); + __clear_bit(nr, addr); +} + +/* * Return the bit position (0..63) of the most significant 1 bit in a word * Returns -1 if no 1 bit exists */ |