diff options
Diffstat (limited to 'arch/blackfin/include/asm/atomic.h')
-rw-r--r-- | arch/blackfin/include/asm/atomic.h | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/atomic.h b/arch/blackfin/include/asm/atomic.h new file mode 100644 index 0000000..7cf5087 --- /dev/null +++ b/arch/blackfin/include/asm/atomic.h @@ -0,0 +1,144 @@ +#ifndef __ARCH_BLACKFIN_ATOMIC__ +#define __ARCH_BLACKFIN_ATOMIC__ + +#include <asm/system.h> /* local_irq_XXX() */ + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc.. + * + * Generally we do not concern about SMP BFIN systems, so we don't have + * to deal with that. + * + * Tony Kou (tonyko@lineo.ca) Lineo Inc. 2001 + */ + +typedef struct { + int counter; +} atomic_t; +#define ATOMIC_INIT(i) { (i) } + +#define atomic_read(v) ((v)->counter) +#define atomic_set(v, i) (((v)->counter) = i) + +static __inline__ void atomic_add(int i, atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter += i; + local_irq_restore(flags); +} + +static __inline__ void atomic_sub(int i, atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter -= i; + local_irq_restore(flags); + +} + +static inline int atomic_add_return(int i, atomic_t * v) +{ + int __temp = 0; + long flags; + + local_irq_save(flags); + v->counter += i; + __temp = v->counter; + local_irq_restore(flags); + + + return __temp; +} + +#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) +static inline int atomic_sub_return(int i, atomic_t * v) +{ + int __temp = 0; + long flags; + + local_irq_save(flags); + v->counter -= i; + __temp = v->counter; + local_irq_restore(flags); + + return __temp; +} + +static __inline__ void atomic_inc(volatile atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter++; + local_irq_restore(flags); +} + +#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) +#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) + +#define atomic_add_unless(v, a, u) \ +({ \ + int c, old; \ + c = atomic_read(v); \ + while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \ + c = old; \ + c != (u); \ +}) +#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) + +static __inline__ void atomic_dec(volatile atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter--; + local_irq_restore(flags); +} + +static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter &= ~mask; + local_irq_restore(flags); +} + +static __inline__ void atomic_set_mask(unsigned int mask, atomic_t * v) +{ + long flags; + + local_irq_save(flags); + v->counter |= mask; + local_irq_restore(flags); +} + +/* Atomic operations are already serializing */ +#define smp_mb__before_atomic_dec() barrier() +#define smp_mb__after_atomic_dec() barrier() +#define smp_mb__before_atomic_inc() barrier() +#define smp_mb__after_atomic_inc() barrier() + +#define atomic_dec_return(v) atomic_sub_return(1,(v)) +#define atomic_inc_return(v) atomic_add_return(1,(v)) + +/* + * atomic_inc_and_test - increment and test + * @v: pointer of type atomic_t + * + * Atomically increments @v by 1 + * and returns true if the result is zero, or false for all + * other cases. + */ +#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) + +#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) +#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) + +#include <asm-generic/atomic.h> + +#endif /* __ARCH_BLACKFIN_ATOMIC __ */ |