diff options
Diffstat (limited to 'kernel/arch/metag/include/asm/cmpxchg_lock1.h')
-rw-r--r-- | kernel/arch/metag/include/asm/cmpxchg_lock1.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/kernel/arch/metag/include/asm/cmpxchg_lock1.h b/kernel/arch/metag/include/asm/cmpxchg_lock1.h new file mode 100644 index 000000000..fd6850474 --- /dev/null +++ b/kernel/arch/metag/include/asm/cmpxchg_lock1.h @@ -0,0 +1,48 @@ +#ifndef __ASM_METAG_CMPXCHG_LOCK1_H +#define __ASM_METAG_CMPXCHG_LOCK1_H + +#include <asm/global_lock.h> + +/* Use LOCK2 as these have to be atomic w.r.t. ordinary accesses. */ + +static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val) +{ + unsigned long flags, retval; + + __global_lock2(flags); + fence(); + retval = *m; + *m = val; + __global_unlock2(flags); + return retval; +} + +static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val) +{ + unsigned long flags, retval; + + __global_lock2(flags); + fence(); + retval = *m; + *m = val & 0xff; + __global_unlock2(flags); + return retval; +} + +static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old, + unsigned long new) +{ + __u32 retval; + unsigned long flags; + + __global_lock2(flags); + retval = *m; + if (retval == old) { + fence(); + *m = new; + } + __global_unlock2(flags); + return retval; +} + +#endif /* __ASM_METAG_CMPXCHG_LOCK1_H */ |