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 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 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 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 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