1 /*
2 * PowerPC atomic operations
3 */
4
5 #ifndef _ASM_PPC_ATOMIC_H_
6 #define _ASM_PPC_ATOMIC_H_
7
8 #ifdef CONFIG_SMP
9 typedef struct { volatile int counter; } atomic_t;
10 #else
11 typedef struct { int counter; } atomic_t;
12 #endif
13
14 #define ATOMIC_INIT(i) { (i) }
15
16 #define atomic_read(v) ((v)->counter)
17 #define atomic_set(v,i) (((v)->counter) = (i))
18
19 extern void atomic_clear_mask(unsigned long mask, unsigned long *addr);
20 extern void atomic_set_mask(unsigned long mask, unsigned long *addr);
21
atomic_add_return(int a,atomic_t * v)22 static __inline__ int atomic_add_return(int a, atomic_t *v)
23 {
24 int t;
25
26 __asm__ __volatile__("\n\
27 1: lwarx %0,0,%3\n\
28 add %0,%2,%0\n\
29 stwcx. %0,0,%3\n\
30 bne- 1b"
31 : "=&r" (t), "=m" (*v)
32 : "r" (a), "r" (v), "m" (*v)
33 : "cc");
34
35 return t;
36 }
37
atomic_sub_return(int a,atomic_t * v)38 static __inline__ int atomic_sub_return(int a, atomic_t *v)
39 {
40 int t;
41
42 __asm__ __volatile__("\n\
43 1: lwarx %0,0,%3\n\
44 subf %0,%2,%0\n\
45 stwcx. %0,0,%3\n\
46 bne- 1b"
47 : "=&r" (t), "=m" (*v)
48 : "r" (a), "r" (v), "m" (*v)
49 : "cc");
50
51 return t;
52 }
53
atomic_inc_return(atomic_t * v)54 static __inline__ int atomic_inc_return(atomic_t *v)
55 {
56 int t;
57
58 __asm__ __volatile__("\n\
59 1: lwarx %0,0,%2\n\
60 addic %0,%0,1\n\
61 stwcx. %0,0,%2\n\
62 bne- 1b"
63 : "=&r" (t), "=m" (*v)
64 : "r" (v), "m" (*v)
65 : "cc");
66
67 return t;
68 }
69
atomic_dec_return(atomic_t * v)70 static __inline__ int atomic_dec_return(atomic_t *v)
71 {
72 int t;
73
74 __asm__ __volatile__("\n\
75 1: lwarx %0,0,%2\n\
76 addic %0,%0,-1\n\
77 stwcx. %0,0,%2\n\
78 bne 1b"
79 : "=&r" (t), "=m" (*v)
80 : "r" (v), "m" (*v)
81 : "cc");
82
83 return t;
84 }
85
86 #define atomic_add(a, v) ((void) atomic_add_return((a), (v)))
87 #define atomic_sub(a, v) ((void) atomic_sub_return((a), (v)))
88 #define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
89 #define atomic_inc(v) ((void) atomic_inc_return((v)))
90 #define atomic_dec(v) ((void) atomic_dec_return((v)))
91 #define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
92
93 #endif /* _ASM_PPC_ATOMIC_H_ */
94