1 /* 2 * PowerPC atomic operations 3 */ 4 5 #ifndef _ASM_PPC_ATOMIC_H_ 6 #define _ASM_PPC_ATOMIC_H_ 7 8 #include <linux/config.h> 9 10 #ifdef CONFIG_SMP 11 typedef struct { volatile int counter; } atomic_t; 12 #else 13 typedef struct { int counter; } atomic_t; 14 #endif 15 16 #define ATOMIC_INIT(i) { (i) } 17 18 #define atomic_read(v) ((v)->counter) 19 #define atomic_set(v,i) (((v)->counter) = (i)) 20 21 extern void atomic_clear_mask(unsigned long mask, unsigned long *addr); 22 extern void atomic_set_mask(unsigned long mask, unsigned long *addr); 23 24 extern __inline__ int atomic_add_return(int a, atomic_t *v) 25 { 26 int t; 27 28 __asm__ __volatile__("\n\ 29 1: lwarx %0,0,%3\n\ 30 add %0,%2,%0\n\ 31 stwcx. %0,0,%3\n\ 32 bne- 1b" 33 : "=&r" (t), "=m" (*v) 34 : "r" (a), "r" (v), "m" (*v) 35 : "cc"); 36 37 return t; 38 } 39 40 extern __inline__ int atomic_sub_return(int a, atomic_t *v) 41 { 42 int t; 43 44 __asm__ __volatile__("\n\ 45 1: lwarx %0,0,%3\n\ 46 subf %0,%2,%0\n\ 47 stwcx. %0,0,%3\n\ 48 bne- 1b" 49 : "=&r" (t), "=m" (*v) 50 : "r" (a), "r" (v), "m" (*v) 51 : "cc"); 52 53 return t; 54 } 55 56 extern __inline__ int atomic_inc_return(atomic_t *v) 57 { 58 int t; 59 60 __asm__ __volatile__("\n\ 61 1: lwarx %0,0,%2\n\ 62 addic %0,%0,1\n\ 63 stwcx. %0,0,%2\n\ 64 bne- 1b" 65 : "=&r" (t), "=m" (*v) 66 : "r" (v), "m" (*v) 67 : "cc"); 68 69 return t; 70 } 71 72 extern __inline__ int atomic_dec_return(atomic_t *v) 73 { 74 int t; 75 76 __asm__ __volatile__("\n\ 77 1: lwarx %0,0,%2\n\ 78 addic %0,%0,-1\n\ 79 stwcx. %0,0,%2\n\ 80 bne 1b" 81 : "=&r" (t), "=m" (*v) 82 : "r" (v), "m" (*v) 83 : "cc"); 84 85 return t; 86 } 87 88 #define atomic_add(a, v) ((void) atomic_add_return((a), (v))) 89 #define atomic_sub(a, v) ((void) atomic_sub_return((a), (v))) 90 #define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0) 91 #define atomic_inc(v) ((void) atomic_inc_return((v))) 92 #define atomic_dec(v) ((void) atomic_dec_return((v))) 93 #define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0) 94 95 #endif /* _ASM_PPC_ATOMIC_H_ */ 96