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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef __ARCH_M68K_ATOMIC__
2#define __ARCH_M68K_ATOMIC__
3
4#include <linux/config.h>
5
6#include <asm/system.h> /* local_irq_XXX() */
7
8/*
9 * Atomic operations that C can't guarantee us. Useful for
10 * resource counting etc..
11 */
12
13/*
14 * We do not have SMP m68k systems, so we don't have to deal with that.
15 */
16
17typedef struct { int counter; } atomic_t;
18#define ATOMIC_INIT(i) { (i) }
19
20#define atomic_read(v) ((v)->counter)
21#define atomic_set(v, i) (((v)->counter) = i)
22
23static inline void atomic_add(int i, atomic_t *v)
24{
25 __asm__ __volatile__("addl %1,%0" : "+m" (*v) : "id" (i));
26}
27
28static inline void atomic_sub(int i, atomic_t *v)
29{
30 __asm__ __volatile__("subl %1,%0" : "+m" (*v) : "id" (i));
31}
32
33static inline void atomic_inc(atomic_t *v)
34{
35 __asm__ __volatile__("addql #1,%0" : "+m" (*v));
36}
37
38static inline void atomic_dec(atomic_t *v)
39{
40 __asm__ __volatile__("subql #1,%0" : "+m" (*v));
41}
42
43static inline int atomic_dec_and_test(atomic_t *v)
44{
45 char c;
46 __asm__ __volatile__("subql #1,%1; seq %0" : "=d" (c), "+m" (*v));
47 return c != 0;
48}
49
50static inline int atomic_inc_and_test(atomic_t *v)
51{
52 char c;
53 __asm__ __volatile__("addql #1,%1; seq %0" : "=d" (c), "+m" (*v));
54 return c != 0;
55}
56
57#ifdef CONFIG_RMW_INSNS
58static inline int atomic_add_return(int i, atomic_t *v)
59{
60 int t, tmp;
61
62 __asm__ __volatile__(
63 "1: movel %2,%1\n"
64 " addl %3,%1\n"
65 " casl %2,%1,%0\n"
66 " jne 1b"
67 : "+m" (*v), "=&d" (t), "=&d" (tmp)
68 : "g" (i), "2" (atomic_read(v)));
69 return t;
70}
71
72static inline int atomic_sub_return(int i, atomic_t *v)
73{
74 int t, tmp;
75
76 __asm__ __volatile__(
77 "1: movel %2,%1\n"
78 " subl %3,%1\n"
79 " casl %2,%1,%0\n"
80 " jne 1b"
81 : "+m" (*v), "=&d" (t), "=&d" (tmp)
82 : "g" (i), "2" (atomic_read(v)));
83 return t;
84}
85#else /* !CONFIG_RMW_INSNS */
86static inline int atomic_add_return(int i, atomic_t * v)
87{
88 unsigned long flags;
89 int t;
90
91 local_irq_save(flags);
92 t = atomic_read(v);
93 t += i;
94 atomic_set(v, t);
95 local_irq_restore(flags);
96
97 return t;
98}
99
100static inline int atomic_sub_return(int i, atomic_t * v)
101{
102 unsigned long flags;
103 int t;
104
105 local_irq_save(flags);
106 t = atomic_read(v);
107 t -= i;
108 atomic_set(v, t);
109 local_irq_restore(flags);
110
111 return t;
112}
113#endif /* !CONFIG_RMW_INSNS */
114
115#define atomic_dec_return(v) atomic_sub_return(1, (v))
116#define atomic_inc_return(v) atomic_add_return(1, (v))
117
118static inline int atomic_sub_and_test(int i, atomic_t *v)
119{
120 char c;
121 __asm__ __volatile__("subl %2,%1; seq %0" : "=d" (c), "+m" (*v): "g" (i));
122 return c != 0;
123}
124
125static inline int atomic_add_negative(int i, atomic_t *v)
126{
127 char c;
128 __asm__ __volatile__("addl %2,%1; smi %0" : "=d" (c), "+m" (*v): "g" (i));
129 return c != 0;
130}
131
132static inline void atomic_clear_mask(unsigned long mask, unsigned long *v)
133{
134 __asm__ __volatile__("andl %1,%0" : "+m" (*v) : "id" (~(mask)));
135}
136
137static inline void atomic_set_mask(unsigned long mask, unsigned long *v)
138{
139 __asm__ __volatile__("orl %1,%0" : "+m" (*v) : "id" (mask));
140}
141
142/* Atomic operations are already serializing */
143#define smp_mb__before_atomic_dec() barrier()
144#define smp_mb__after_atomic_dec() barrier()
145#define smp_mb__before_atomic_inc() barrier()
146#define smp_mb__after_atomic_inc() barrier()
147
148#endif /* __ARCH_M68K_ATOMIC __ */