summaryrefslogtreecommitdiff
path: root/arch/mips/include/asm/barrier.h
blob: 7ecba84656d4951a4196622344338c842997fb0f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2006 by Ralf Baechle (ralf@linux-mips.org)
 */
#ifndef __ASM_BARRIER_H
#define __ASM_BARRIER_H

#include <asm/addrspace.h>

#define read_barrier_depends()		do { } while(0)
#define smp_read_barrier_depends()	do { } while(0)

#ifdef CONFIG_CPU_HAS_SYNC
#define __sync()				\
	__asm__ __volatile__(			\
		".set	push\n\t"		\
		".set	noreorder\n\t"		\
		".set	mips2\n\t"		\
		"sync\n\t"			\
		".set	pop"			\
		: /* no output */		\
		: /* no input */		\
		: "memory")
#else
#define __sync()	do { } while(0)
#endif

#define __fast_iob()				\
	__asm__ __volatile__(			\
		".set	push\n\t"		\
		".set	noreorder\n\t"		\
		"lw	$0,%0\n\t"		\
		"nop\n\t"			\
		".set	pop"			\
		: /* no output */		\
		: "m" (*(int *)CKSEG1)		\
		: "memory")
#ifdef CONFIG_CPU_CAVIUM_OCTEON
# define OCTEON_SYNCW_STR	".set push\n.set arch=octeon\nsyncw\nsyncw\n.set pop\n"
# define __syncw()	__asm__ __volatile__(OCTEON_SYNCW_STR : : : "memory")

# define fast_wmb()	__syncw()
# define fast_rmb()	barrier()
# define fast_mb()	__sync()
# define fast_iob()	do { } while (0)
#else /* ! CONFIG_CPU_CAVIUM_OCTEON */
# define fast_wmb()	__sync()
# define fast_rmb()	__sync()
# define fast_mb()	__sync()
# ifdef CONFIG_SGI_IP28
#  define fast_iob()				\
	__asm__ __volatile__(			\
		".set	push\n\t"		\
		".set	noreorder\n\t"		\
		"lw	$0,%0\n\t"		\
		"sync\n\t"			\
		"lw	$0,%0\n\t"		\
		".set	pop"			\
		: /* no output */		\
		: "m" (*(int *)CKSEG1ADDR(0x1fa00004)) \
		: "memory")
# else
#  define fast_iob()				\
	do {					\
		__sync();			\
		__fast_iob();			\
	} while (0)
# endif
#endif /* CONFIG_CPU_CAVIUM_OCTEON */

#ifdef CONFIG_CPU_HAS_WB

#include <asm/wbflush.h>

#define mb()		wbflush()
#define iob()		wbflush()

#else /* !CONFIG_CPU_HAS_WB */

#define mb()		fast_mb()
#define iob()		fast_iob()

#endif /* !CONFIG_CPU_HAS_WB */

#define wmb()		fast_wmb()
#define rmb()		fast_rmb()
#define dma_wmb()	fast_wmb()
#define dma_rmb()	fast_rmb()

#if defined(CONFIG_WEAK_ORDERING) && defined(CONFIG_SMP)
# ifdef CONFIG_CPU_CAVIUM_OCTEON
#  define smp_mb()	__sync()
#  define smp_rmb()	barrier()
#  define smp_wmb()	__syncw()
# else
#  define smp_mb()	__asm__ __volatile__("sync" : : :"memory")
#  define smp_rmb()	__asm__ __volatile__("sync" : : :"memory")
#  define smp_wmb()	__asm__ __volatile__("sync" : : :"memory")
# endif
#else
#define smp_mb()	barrier()
#define smp_rmb()	barrier()
#define smp_wmb()	barrier()
#endif

#if defined(CONFIG_WEAK_REORDERING_BEYOND_LLSC) && defined(CONFIG_SMP)
#define __WEAK_LLSC_MB		"	sync	\n"
#else
#define __WEAK_LLSC_MB		"		\n"
#endif

#define smp_store_mb(var, value) \
	do { WRITE_ONCE(var, value); smp_mb(); } while (0)

#define smp_llsc_mb()	__asm__ __volatile__(__WEAK_LLSC_MB : : :"memory")

#ifdef CONFIG_CPU_CAVIUM_OCTEON
#define smp_mb__before_llsc() smp_wmb()
/* Cause previous writes to become visible on all CPUs as soon as possible */
#define nudge_writes() __asm__ __volatile__(".set push\n\t"		\
					    ".set arch=octeon\n\t"	\
					    "syncw\n\t"			\
					    ".set pop" : : : "memory")
#else
#define smp_mb__before_llsc() smp_llsc_mb()
#define nudge_writes() mb()
#endif

#define smp_store_release(p, v)						\
do {									\
	compiletime_assert_atomic_type(*p);				\
	smp_mb();							\
	ACCESS_ONCE(*p) = (v);						\
} while (0)

#define smp_load_acquire(p)						\
({									\
	typeof(*p) ___p1 = ACCESS_ONCE(*p);				\
	compiletime_assert_atomic_type(*p);				\
	smp_mb();							\
	___p1;								\
})

#define smp_mb__before_atomic()	smp_mb__before_llsc()
#define smp_mb__after_atomic()	smp_llsc_mb()

#endif /* __ASM_BARRIER_H */