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-rw-r--r--include/asm-ppc/atomic.h95
1 files changed, 95 insertions, 0 deletions
diff --git a/include/asm-ppc/atomic.h b/include/asm-ppc/atomic.h
new file mode 100644
index 0000000000..23f22df1b7
--- /dev/null
+++ b/include/asm-ppc/atomic.h
@@ -0,0 +1,95 @@
+/*
+ * PowerPC atomic operations
+ */
+
+#ifndef _ASM_PPC_ATOMIC_H_
+#define _ASM_PPC_ATOMIC_H_
+
+#include <linux/config.h>
+
+#ifdef CONFIG_SMP
+typedef struct { volatile int counter; } atomic_t;
+#else
+typedef struct { int counter; } atomic_t;
+#endif
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+extern void atomic_clear_mask(unsigned long mask, unsigned long *addr);
+extern void atomic_set_mask(unsigned long mask, unsigned long *addr);
+
+extern __inline__ int atomic_add_return(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__("\n\
+1: lwarx %0,0,%3\n\
+ add %0,%2,%0\n\
+ stwcx. %0,0,%3\n\
+ bne- 1b"
+ : "=&r" (t), "=m" (*v)
+ : "r" (a), "r" (v), "m" (*v)
+ : "cc");
+
+ return t;
+}
+
+extern __inline__ int atomic_sub_return(int a, atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__("\n\
+1: lwarx %0,0,%3\n\
+ subf %0,%2,%0\n\
+ stwcx. %0,0,%3\n\
+ bne- 1b"
+ : "=&r" (t), "=m" (*v)
+ : "r" (a), "r" (v), "m" (*v)
+ : "cc");
+
+ return t;
+}
+
+extern __inline__ int atomic_inc_return(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__("\n\
+1: lwarx %0,0,%2\n\
+ addic %0,%0,1\n\
+ stwcx. %0,0,%2\n\
+ bne- 1b"
+ : "=&r" (t), "=m" (*v)
+ : "r" (v), "m" (*v)
+ : "cc");
+
+ return t;
+}
+
+extern __inline__ int atomic_dec_return(atomic_t *v)
+{
+ int t;
+
+ __asm__ __volatile__("\n\
+1: lwarx %0,0,%2\n\
+ addic %0,%0,-1\n\
+ stwcx. %0,0,%2\n\
+ bne 1b"
+ : "=&r" (t), "=m" (*v)
+ : "r" (v), "m" (*v)
+ : "cc");
+
+ return t;
+}
+
+#define atomic_add(a, v) ((void) atomic_add_return((a), (v)))
+#define atomic_sub(a, v) ((void) atomic_sub_return((a), (v)))
+#define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
+#define atomic_inc(v) ((void) atomic_inc_return((v)))
+#define atomic_dec(v) ((void) atomic_dec_return((v)))
+#define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
+
+#endif /* _ASM_PPC_ATOMIC_H_ */