xref: /openbmc/linux/arch/csky/include/asm/barrier.h (revision da1d9caf)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef __ASM_CSKY_BARRIER_H
4 #define __ASM_CSKY_BARRIER_H
5 
6 #ifndef __ASSEMBLY__
7 
8 #define nop()	asm volatile ("nop\n":::"memory")
9 
10 #ifdef CONFIG_SMP
11 
12 /*
13  * bar.brwarws: ordering barrier for all load/store instructions
14  *              before/after
15  *
16  * |31|30 26|25 21|20 16|15  10|9   5|4           0|
17  *  1  10000 00000 00000 100001	00001 0 bw br aw ar
18  *
19  * b: before
20  * a: after
21  * r: read
22  * w: write
23  *
24  * Here are all combinations:
25  *
26  * bar.brw
27  * bar.br
28  * bar.bw
29  * bar.arw
30  * bar.ar
31  * bar.aw
32  * bar.brwarw
33  * bar.brarw
34  * bar.bwarw
35  * bar.brwar
36  * bar.brwaw
37  * bar.brar
38  * bar.bwaw
39  */
40 #define FULL_FENCE		".long 0x842fc000\n"
41 #define ACQUIRE_FENCE		".long 0x8427c000\n"
42 #define RELEASE_FENCE		".long 0x842ec000\n"
43 
44 #define __bar_brw()	asm volatile (".long 0x842cc000\n":::"memory")
45 #define __bar_br()	asm volatile (".long 0x8424c000\n":::"memory")
46 #define __bar_bw()	asm volatile (".long 0x8428c000\n":::"memory")
47 #define __bar_arw()	asm volatile (".long 0x8423c000\n":::"memory")
48 #define __bar_ar()	asm volatile (".long 0x8421c000\n":::"memory")
49 #define __bar_aw()	asm volatile (".long 0x8422c000\n":::"memory")
50 #define __bar_brwarw()	asm volatile (FULL_FENCE:::"memory")
51 #define __bar_brarw()	asm volatile (ACQUIRE_FENCE:::"memory")
52 #define __bar_bwarw()	asm volatile (".long 0x842bc000\n":::"memory")
53 #define __bar_brwar()	asm volatile (".long 0x842dc000\n":::"memory")
54 #define __bar_brwaw()	asm volatile (RELEASE_FENCE:::"memory")
55 #define __bar_brar()	asm volatile (".long 0x8425c000\n":::"memory")
56 #define __bar_brar()	asm volatile (".long 0x8425c000\n":::"memory")
57 #define __bar_bwaw()	asm volatile (".long 0x842ac000\n":::"memory")
58 
59 #define __smp_mb()	__bar_brwarw()
60 #define __smp_rmb()	__bar_brar()
61 #define __smp_wmb()	__bar_bwaw()
62 
63 #define __smp_acquire_fence()	__bar_brarw()
64 #define __smp_release_fence()	__bar_brwaw()
65 
66 #endif /* CONFIG_SMP */
67 
68 /*
69  * sync:        completion barrier, all sync.xx instructions
70  *              guarantee the last response received by bus transaction
71  *              made by ld/st instructions before sync.s
72  * sync.s:      inherit from sync, but also shareable to other cores
73  * sync.i:      inherit from sync, but also flush cpu pipeline
74  * sync.is:     the same with sync.i + sync.s
75  */
76 #define mb()		asm volatile ("sync\n":::"memory")
77 
78 #ifdef CONFIG_CPU_HAS_CACHEV2
79 /*
80  * Using three sync.is to prevent speculative PTW
81  */
82 #define sync_is()	asm volatile ("sync.is\nsync.is\nsync.is\n":::"memory")
83 #endif
84 
85 #include <asm-generic/barrier.h>
86 
87 #endif /* __ASSEMBLY__ */
88 #endif /* __ASM_CSKY_BARRIER_H */
89