diff options
Diffstat (limited to 'arch/arm64/include/asm/atomic_lse.h')
| -rw-r--r-- | arch/arm64/include/asm/atomic_lse.h | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/atomic_lse.h b/arch/arm64/include/asm/atomic_lse.h index 6e21b5e0c9d6..b39ae4c1451a 100644 --- a/arch/arm64/include/asm/atomic_lse.h +++ b/arch/arm64/include/asm/atomic_lse.h @@ -349,4 +349,43 @@ static inline long atomic64_dec_if_positive(atomic64_t *v) #undef __LL_SC_ATOMIC64 +#define __LL_SC_CMPXCHG(op) __LL_SC_CALL(__cmpxchg_case_##op) + +#define __CMPXCHG_CASE(w, sz, name, mb, cl...) \ +static inline unsigned long __cmpxchg_case_##name(volatile void *ptr, \ + unsigned long old, \ + unsigned long new) \ +{ \ + register unsigned long x0 asm ("x0") = (unsigned long)ptr; \ + register unsigned long x1 asm ("x1") = old; \ + register unsigned long x2 asm ("x2") = new; \ + \ + asm volatile(ARM64_LSE_ATOMIC_INSN( \ + /* LL/SC */ \ + "nop\n" \ + __LL_SC_CMPXCHG(name) \ + "nop", \ + /* LSE atomics */ \ + " mov " #w "30, %" #w "[old]\n" \ + " cas" #mb #sz "\t" #w "30, %" #w "[new], %[v]\n" \ + " mov %" #w "[ret], " #w "30") \ + : [ret] "+r" (x0), [v] "+Q" (*(unsigned long *)ptr) \ + : [old] "r" (x1), [new] "r" (x2) \ + : "x30" , ##cl); \ + \ + return x0; \ +} + +__CMPXCHG_CASE(w, b, 1, ) +__CMPXCHG_CASE(w, h, 2, ) +__CMPXCHG_CASE(w, , 4, ) +__CMPXCHG_CASE(x, , 8, ) +__CMPXCHG_CASE(w, b, mb_1, al, "memory") +__CMPXCHG_CASE(w, h, mb_2, al, "memory") +__CMPXCHG_CASE(w, , mb_4, al, "memory") +__CMPXCHG_CASE(x, , mb_8, al, "memory") + +#undef __LL_SC_CMPXCHG +#undef __CMPXCHG_CASE + #endif /* __ASM_ATOMIC_LSE_H */ |