diff options
Diffstat (limited to 'arch/arm/atomic.h')
| -rw-r--r-- | arch/arm/atomic.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/arm/atomic.h b/arch/arm/atomic.h index 734d2871..fe88225b 100644 --- a/arch/arm/atomic.h +++ b/arch/arm/atomic.h @@ -22,7 +22,28 @@ static inline int a_ctz_64(uint64_t x) return a_ctz_l(y); } +#if __ARM_ARCH_6__ || __ARM_ARCH_6K__ || __ARM_ARCH_6ZK__ \ + || __ARM_ARCH_7A__ || __ARM_ARCH_7R__ \ + || __ARM_ARCH >= 7 +static inline int __k_cas(int t, int s, volatile int *p) +{ + int ret; + __asm__( + " mcr p15,0,r0,c7,c10,5\n" + "1: ldrex %0,%3\n" + " subs %0,%0,%1\n" + " strexeq %0,%2,%3\n" + " teqeq %0,#1\n" + " beq 1b\n" + " mcr p15,0,r0,c7,c10,5\n" + : "=&r"(ret) + : "r"(t), "r"(s), "m"(*p) + : "memory", "cc" ); + return ret; +} +#else #define __k_cas ((int (*)(int, int, volatile int *))0xffff0fc0) +#endif static inline int a_cas(volatile int *p, int t, int s) { |