xref: /openbmc/linux/arch/s390/include/asm/barrier.h (revision 78700c0a)
1 /*
2  * Copyright IBM Corp. 1999, 2009
3  *
4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5  */
6 
7 #ifndef __ASM_BARRIER_H
8 #define __ASM_BARRIER_H
9 
10 /*
11  * Force strict CPU ordering.
12  * And yes, this is required on UP too when we're talking
13  * to devices.
14  */
15 
16 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
17 /* Fast-BCR without checkpoint synchronization */
18 #define __ASM_BARRIER "bcr 14,0\n"
19 #else
20 #define __ASM_BARRIER "bcr 15,0\n"
21 #endif
22 
23 #define mb() do {  asm volatile(__ASM_BARRIER : : : "memory"); } while (0)
24 
25 #define rmb()				barrier()
26 #define wmb()				barrier()
27 #define dma_rmb()			mb()
28 #define dma_wmb()			mb()
29 #define __smp_mb()			mb()
30 #define __smp_rmb()			rmb()
31 #define __smp_wmb()			wmb()
32 
33 #define __smp_store_release(p, v)					\
34 do {									\
35 	compiletime_assert_atomic_type(*p);				\
36 	barrier();							\
37 	WRITE_ONCE(*p, v);						\
38 } while (0)
39 
40 #define __smp_load_acquire(p)						\
41 ({									\
42 	typeof(*p) ___p1 = READ_ONCE(*p);				\
43 	compiletime_assert_atomic_type(*p);				\
44 	barrier();							\
45 	___p1;								\
46 })
47 
48 #define __smp_mb__before_atomic()	barrier()
49 #define __smp_mb__after_atomic()	barrier()
50 
51 #include <asm-generic/barrier.h>
52 
53 #endif /* __ASM_BARRIER_H */
54