Initial revision

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_ */