1 /*
2 * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
3 *
4 * This file is licensed under the terms of the GNU General Public License
5 * version 2. This program is licensed "as is" without any warranty of any
6 * kind, whether express or implied.
7 */
8
9 #ifndef __ASM_OPENRISC_ATOMIC_H
10 #define __ASM_OPENRISC_ATOMIC_H
11
12 #include <linux/types.h>
13
14 /* Atomically perform op with v->counter and i */
15 #define ATOMIC_OP(op) \
16 static inline void atomic_##op(int i, atomic_t *v) \
17 { \
18 int tmp; \
19 \
20 __asm__ __volatile__( \
21 "1: l.lwa %0,0(%1) \n" \
22 " l." #op " %0,%0,%2 \n" \
23 " l.swa 0(%1),%0 \n" \
24 " l.bnf 1b \n" \
25 " l.nop \n" \
26 : "=&r"(tmp) \
27 : "r"(&v->counter), "r"(i) \
28 : "cc", "memory"); \
29 }
30
31 /* Atomically perform op with v->counter and i, return the result */
32 #define ATOMIC_OP_RETURN(op) \
33 static inline int atomic_##op##_return(int i, atomic_t *v) \
34 { \
35 int tmp; \
36 \
37 __asm__ __volatile__( \
38 "1: l.lwa %0,0(%1) \n" \
39 " l." #op " %0,%0,%2 \n" \
40 " l.swa 0(%1),%0 \n" \
41 " l.bnf 1b \n" \
42 " l.nop \n" \
43 : "=&r"(tmp) \
44 : "r"(&v->counter), "r"(i) \
45 : "cc", "memory"); \
46 \
47 return tmp; \
48 }
49
50 /* Atomically perform op with v->counter and i, return orig v->counter */
51 #define ATOMIC_FETCH_OP(op) \
52 static inline int atomic_fetch_##op(int i, atomic_t *v) \
53 { \
54 int tmp, old; \
55 \
56 __asm__ __volatile__( \
57 "1: l.lwa %0,0(%2) \n" \
58 " l." #op " %1,%0,%3 \n" \
59 " l.swa 0(%2),%1 \n" \
60 " l.bnf 1b \n" \
61 " l.nop \n" \
62 : "=&r"(old), "=&r"(tmp) \
63 : "r"(&v->counter), "r"(i) \
64 : "cc", "memory"); \
65 \
66 return old; \
67 }
68
69 ATOMIC_OP_RETURN(add)
70 ATOMIC_OP_RETURN(sub)
71
72 ATOMIC_FETCH_OP(add)
73 ATOMIC_FETCH_OP(sub)
74 ATOMIC_FETCH_OP(and)
75 ATOMIC_FETCH_OP(or)
76 ATOMIC_FETCH_OP(xor)
77
78 ATOMIC_OP(and)
79 ATOMIC_OP(or)
80 ATOMIC_OP(xor)
81
82 #undef ATOMIC_FETCH_OP
83 #undef ATOMIC_OP_RETURN
84 #undef ATOMIC_OP
85
86 #define atomic_add_return atomic_add_return
87 #define atomic_sub_return atomic_sub_return
88 #define atomic_fetch_add atomic_fetch_add
89 #define atomic_fetch_sub atomic_fetch_sub
90 #define atomic_fetch_and atomic_fetch_and
91 #define atomic_fetch_or atomic_fetch_or
92 #define atomic_fetch_xor atomic_fetch_xor
93 #define atomic_and atomic_and
94 #define atomic_or atomic_or
95 #define atomic_xor atomic_xor
96
97 /*
98 * Atomically add a to v->counter as long as v is not already u.
99 * Returns the original value at v->counter.
100 *
101 * This is often used through atomic_inc_not_zero()
102 */
103 static inline int atomic_fetch_add_unless(atomic_t *v, int a, int u)
104 {
105 int old, tmp;
106
107 __asm__ __volatile__(
108 "1: l.lwa %0, 0(%2) \n"
109 " l.sfeq %0, %4 \n"
110 " l.bf 2f \n"
111 " l.add %1, %0, %3 \n"
112 " l.swa 0(%2), %1 \n"
113 " l.bnf 1b \n"
114 " l.nop \n"
115 "2: \n"
116 : "=&r"(old), "=&r" (tmp)
117 : "r"(&v->counter), "r"(a), "r"(u)
118 : "cc", "memory");
119
120 return old;
121 }
122 #define atomic_fetch_add_unless atomic_fetch_add_unless
123
124 #include <asm-generic/atomic.h>
125
126 #endif /* __ASM_OPENRISC_ATOMIC_H */