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8#ifndef __ASM_BARRIER_H
9#define __ASM_BARRIER_H
10
11#include <asm/addrspace.h>
12
13#define read_barrier_depends() do { } while(0)
14#define smp_read_barrier_depends() do { } while(0)
15
16#ifdef CONFIG_CPU_HAS_SYNC
17#define __sync() \
18 __asm__ __volatile__( \
19 ".set push\n\t" \
20 ".set noreorder\n\t" \
21 ".set mips2\n\t" \
22 "sync\n\t" \
23 ".set pop" \
24 : \
25 : \
26 : "memory")
27#else
28#define __sync() do { } while(0)
29#endif
30
31#define __fast_iob() \
32 __asm__ __volatile__( \
33 ".set push\n\t" \
34 ".set noreorder\n\t" \
35 "lw $0,%0\n\t" \
36 "nop\n\t" \
37 ".set pop" \
38 : \
39 : "m" (*(int *)CKSEG1) \
40 : "memory")
41#ifdef CONFIG_CPU_CAVIUM_OCTEON
42# define OCTEON_SYNCW_STR ".set push\n.set arch=octeon\nsyncw\nsyncw\n.set pop\n"
43# define __syncw() __asm__ __volatile__(OCTEON_SYNCW_STR : : : "memory")
44
45# define fast_wmb() __syncw()
46# define fast_rmb() barrier()
47# define fast_mb() __sync()
48# define fast_iob() do { } while (0)
49#else
50# define fast_wmb() __sync()
51# define fast_rmb() __sync()
52# define fast_mb() __sync()
53# ifdef CONFIG_SGI_IP28
54# define fast_iob() \
55 __asm__ __volatile__( \
56 ".set push\n\t" \
57 ".set noreorder\n\t" \
58 "lw $0,%0\n\t" \
59 "sync\n\t" \
60 "lw $0,%0\n\t" \
61 ".set pop" \
62 : \
63 : "m" (*(int *)CKSEG1ADDR(0x1fa00004)) \
64 : "memory")
65# else
66# define fast_iob() \
67 do { \
68 __sync(); \
69 __fast_iob(); \
70 } while (0)
71# endif
72#endif
73
74#ifdef CONFIG_CPU_HAS_WB
75
76#include <asm/wbflush.h>
77
78#define mb() wbflush()
79#define iob() wbflush()
80
81#else
82
83#define mb() fast_mb()
84#define iob() fast_iob()
85
86#endif
87
88#define wmb() fast_wmb()
89#define rmb() fast_rmb()
90#define dma_wmb() fast_wmb()
91#define dma_rmb() fast_rmb()
92
93#if defined(CONFIG_WEAK_ORDERING) && defined(CONFIG_SMP)
94# ifdef CONFIG_CPU_CAVIUM_OCTEON
95# define smp_mb() __sync()
96# define smp_rmb() barrier()
97# define smp_wmb() __syncw()
98# else
99# define smp_mb() __asm__ __volatile__("sync" : : :"memory")
100# define smp_rmb() __asm__ __volatile__("sync" : : :"memory")
101# define smp_wmb() __asm__ __volatile__("sync" : : :"memory")
102# endif
103#else
104#define smp_mb() barrier()
105#define smp_rmb() barrier()
106#define smp_wmb() barrier()
107#endif
108
109#if defined(CONFIG_WEAK_REORDERING_BEYOND_LLSC) && defined(CONFIG_SMP)
110#define __WEAK_LLSC_MB " sync \n"
111#else
112#define __WEAK_LLSC_MB " \n"
113#endif
114
115#define smp_store_mb(var, value) \
116 do { WRITE_ONCE(var, value); smp_mb(); } while (0)
117
118#define smp_llsc_mb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory")
119
120#ifdef CONFIG_CPU_CAVIUM_OCTEON
121#define smp_mb__before_llsc() smp_wmb()
122
123#define nudge_writes() __asm__ __volatile__(".set push\n\t" \
124 ".set arch=octeon\n\t" \
125 "syncw\n\t" \
126 ".set pop" : : : "memory")
127#else
128#define smp_mb__before_llsc() smp_llsc_mb()
129#define nudge_writes() mb()
130#endif
131
132#define smp_store_release(p, v) \
133do { \
134 compiletime_assert_atomic_type(*p); \
135 smp_mb(); \
136 WRITE_ONCE(*p, v); \
137} while (0)
138
139#define smp_load_acquire(p) \
140({ \
141 typeof(*p) ___p1 = READ_ONCE(*p); \
142 compiletime_assert_atomic_type(*p); \
143 smp_mb(); \
144 ___p1; \
145})
146
147#define smp_mb__before_atomic() smp_mb__before_llsc()
148#define smp_mb__after_atomic() smp_llsc_mb()
149
150#endif
151