/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __ASM_BARRIER_H #define __ASM_BARRIER_H #include <asm/alternative.h> #ifndef __ASSEMBLY__ /* The synchronize caches instruction executes as a nop on systems in which all memory references are performed in order. */ #define synchronize_caches() asm volatile("sync" \ ALTERNATIVE(ALT_COND_NO_SMP, INSN_NOP) \ : : : "memory") #if defined(CONFIG_SMP) #define mb() do { synchronize_caches(); } while (0) #define rmb() mb() #define wmb() mb() #define dma_rmb() mb() #define dma_wmb() mb() #else #define mb() barrier() #define rmb() barrier() #define wmb() barrier() #define dma_rmb() barrier() #define dma_wmb() barrier() #endif #define __smp_mb() mb() #define __smp_rmb() mb() #define __smp_wmb() mb() #define __smp_store_release(p, v) \ do { \ typeof(p) __p = (p); \ union { typeof(*p) __val; char __c[1]; } __u = \ { .__val = (__force typeof(*p)) (v) }; \ compiletime_assert_atomic_type(*p); \ switch (sizeof(*p)) { \ case 1: \ asm volatile("stb,ma %0,0(%1)" \ : : "r"(*(__u8 *)__u.__c), "r"(__p) \ : "memory"); \ break; \ case 2: \ asm volatile("sth,ma %0,0(%1)" \ : : "r"(*(__u16 *)__u.__c), "r"(__p) \ : "memory"); \ break; \ case 4: \ asm volatile("stw,ma %0,0(%1)" \ : : "r"(*(__u32 *)__u.__c), "r"(__p) \ : "memory"); \ break; \ case 8: \ if (IS_ENABLED(CONFIG_64BIT)) \ asm volatile("std,ma %0,0(%1)" \ : : "r"(*(__u64 *)__u.__c), "r"(__p) \ : "memory"); \ break; \ } \ } while (0) #define __smp_load_acquire(p) \ ({ \ union { typeof(*p) __val; char __c[1]; } __u; \ typeof(p) __p = (p); \ compiletime_assert_atomic_type(*p); \ switch (sizeof(*p)) { \ case 1: \ asm volatile("ldb,ma 0(%1),%0" \ : "=r"(*(__u8 *)__u.__c) : "r"(__p) \ : "memory"); \ break; \ case 2: \ asm volatile("ldh,ma 0(%1),%0" \ : "=r"(*(__u16 *)__u.__c) : "r"(__p) \ : "memory"); \ break; \ case 4: \ asm volatile("ldw,ma 0(%1),%0" \ : "=r"(*(__u32 *)__u.__c) : "r"(__p) \ : "memory"); \ break; \ case 8: \ if (IS_ENABLED(CONFIG_64BIT)) \ asm volatile("ldd,ma 0(%1),%0" \ : "=r"(*(__u64 *)__u.__c) : "r"(__p) \ : "memory"); \ break; \ } \ __u.__val; \ }) #include <asm-generic/barrier.h> #endif /* !__ASSEMBLY__ */ #endif /* __ASM_BARRIER_H */