1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copied from the kernel sources:
4 *
5 * Copyright IBM Corp. 1999, 2009
6 *
7 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
8 */
9
10 #ifndef __TOOLS_LINUX_ASM_BARRIER_H
11 #define __TOOLS_LINUX_ASM_BARRIER_H
12
13 /*
14 * Force strict CPU ordering.
15 * And yes, this is required on UP too when we're talking
16 * to devices.
17 */
18
19 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
20 /* Fast-BCR without checkpoint synchronization */
21 #define __ASM_BARRIER "bcr 14,0\n"
22 #else
23 #define __ASM_BARRIER "bcr 15,0\n"
24 #endif
25
26 #define mb() do { asm volatile(__ASM_BARRIER : : : "memory"); } while (0)
27
28 #define rmb() mb()
29 #define wmb() mb()
30
31 #define smp_store_release(p, v) \
32 do { \
33 barrier(); \
34 WRITE_ONCE(*p, v); \
35 } while (0)
36
37 #define smp_load_acquire(p) \
38 ({ \
39 typeof(*p) ___p1 = READ_ONCE(*p); \
40 barrier(); \
41 ___p1; \
42 })
43
44 #endif /* __TOOLS_LIB_ASM_BARRIER_H */