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Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5#ifndef __ASM_BARRIER_H
6#define __ASM_BARRIER_H
7
8#define __sync() __asm__ __volatile__("dbar 0" : : : "memory")
9
10#define fast_wmb() __sync()
11#define fast_rmb() __sync()
12#define fast_mb() __sync()
13#define fast_iob() __sync()
14#define wbflush() __sync()
15
16#define wmb() fast_wmb()
17#define rmb() fast_rmb()
18#define mb() fast_mb()
19#define iob() fast_iob()
20
21#define __smp_mb() __asm__ __volatile__("dbar 0" : : : "memory")
22#define __smp_rmb() __asm__ __volatile__("dbar 0" : : : "memory")
23#define __smp_wmb() __asm__ __volatile__("dbar 0" : : : "memory")
24
25#ifdef CONFIG_SMP
26#define __WEAK_LLSC_MB " dbar 0 \n"
27#else
28#define __WEAK_LLSC_MB " \n"
29#endif
30
31#define __smp_mb__before_atomic() barrier()
32#define __smp_mb__after_atomic() barrier()
33
34/**
35 * array_index_mask_nospec() - generate a ~0 mask when index < size, 0 otherwise
36 * @index: array element index
37 * @size: number of elements in array
38 *
39 * Returns:
40 * 0 - (@index < @size)
41 */
42#define array_index_mask_nospec array_index_mask_nospec
43static inline unsigned long array_index_mask_nospec(unsigned long index,
44 unsigned long size)
45{
46 unsigned long mask;
47
48 __asm__ __volatile__(
49 "sltu %0, %1, %2\n\t"
50#if (__SIZEOF_LONG__ == 4)
51 "sub.w %0, $zero, %0\n\t"
52#elif (__SIZEOF_LONG__ == 8)
53 "sub.d %0, $zero, %0\n\t"
54#endif
55 : "=r" (mask)
56 : "r" (index), "r" (size)
57 :);
58
59 return mask;
60}
61
62#define __smp_load_acquire(p) \
63({ \
64 union { typeof(*p) __val; char __c[1]; } __u; \
65 unsigned long __tmp = 0; \
66 compiletime_assert_atomic_type(*p); \
67 switch (sizeof(*p)) { \
68 case 1: \
69 *(__u8 *)__u.__c = *(volatile __u8 *)p; \
70 __smp_mb(); \
71 break; \
72 case 2: \
73 *(__u16 *)__u.__c = *(volatile __u16 *)p; \
74 __smp_mb(); \
75 break; \
76 case 4: \
77 __asm__ __volatile__( \
78 "amor_db.w %[val], %[tmp], %[mem] \n" \
79 : [val] "=&r" (*(__u32 *)__u.__c) \
80 : [mem] "ZB" (*(u32 *) p), [tmp] "r" (__tmp) \
81 : "memory"); \
82 break; \
83 case 8: \
84 __asm__ __volatile__( \
85 "amor_db.d %[val], %[tmp], %[mem] \n" \
86 : [val] "=&r" (*(__u64 *)__u.__c) \
87 : [mem] "ZB" (*(u64 *) p), [tmp] "r" (__tmp) \
88 : "memory"); \
89 break; \
90 } \
91 (typeof(*p))__u.__val; \
92})
93
94#define __smp_store_release(p, v) \
95do { \
96 union { typeof(*p) __val; char __c[1]; } __u = \
97 { .__val = (__force typeof(*p)) (v) }; \
98 unsigned long __tmp; \
99 compiletime_assert_atomic_type(*p); \
100 switch (sizeof(*p)) { \
101 case 1: \
102 __smp_mb(); \
103 *(volatile __u8 *)p = *(__u8 *)__u.__c; \
104 break; \
105 case 2: \
106 __smp_mb(); \
107 *(volatile __u16 *)p = *(__u16 *)__u.__c; \
108 break; \
109 case 4: \
110 __asm__ __volatile__( \
111 "amswap_db.w %[tmp], %[val], %[mem] \n" \
112 : [mem] "+ZB" (*(u32 *)p), [tmp] "=&r" (__tmp) \
113 : [val] "r" (*(__u32 *)__u.__c) \
114 : ); \
115 break; \
116 case 8: \
117 __asm__ __volatile__( \
118 "amswap_db.d %[tmp], %[val], %[mem] \n" \
119 : [mem] "+ZB" (*(u64 *)p), [tmp] "=&r" (__tmp) \
120 : [val] "r" (*(__u64 *)__u.__c) \
121 : ); \
122 break; \
123 } \
124} while (0)
125
126#define __smp_store_mb(p, v) \
127do { \
128 union { typeof(p) __val; char __c[1]; } __u = \
129 { .__val = (__force typeof(p)) (v) }; \
130 unsigned long __tmp; \
131 switch (sizeof(p)) { \
132 case 1: \
133 *(volatile __u8 *)&p = *(__u8 *)__u.__c; \
134 __smp_mb(); \
135 break; \
136 case 2: \
137 *(volatile __u16 *)&p = *(__u16 *)__u.__c; \
138 __smp_mb(); \
139 break; \
140 case 4: \
141 __asm__ __volatile__( \
142 "amswap_db.w %[tmp], %[val], %[mem] \n" \
143 : [mem] "+ZB" (*(u32 *)&p), [tmp] "=&r" (__tmp) \
144 : [val] "r" (*(__u32 *)__u.__c) \
145 : ); \
146 break; \
147 case 8: \
148 __asm__ __volatile__( \
149 "amswap_db.d %[tmp], %[val], %[mem] \n" \
150 : [mem] "+ZB" (*(u64 *)&p), [tmp] "=&r" (__tmp) \
151 : [val] "r" (*(__u64 *)__u.__c) \
152 : ); \
153 break; \
154 } \
155} while (0)
156
157#include <asm-generic/barrier.h>
158
159#endif /* __ASM_BARRIER_H */