1 files changed, 136 insertions, 0 deletions
diff --git a/arch/openrisc/include/asm/atomic.h b/arch/openrisc/include/asm/atomic.h
new file mode 100644
index 000000000..326167e47
--- /dev/null
+++ b/arch/openrisc/include/asm/atomic.h
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#ifndef __ASM_OPENRISC_ATOMIC_H
+#define __ASM_OPENRISC_ATOMIC_H
+
+#include <linux/types.h>
+
+/* Atomically perform op with v->counter and i */
+#define ATOMIC_OP(op)							\
+static inline void arch_atomic_##op(int i, atomic_t *v)			\
+{									\
+	int tmp;							\
+									\
+	__asm__ __volatile__(						\
+		"1:	l.lwa	%0,0(%1)	\n"			\
+		"	l." #op " %0,%0,%2	\n"			\
+		"	l.swa	0(%1),%0	\n"			\
+		"	l.bnf	1b		\n"			\
+		"	 l.nop			\n"			\
+		: "=&r"(tmp)						\
+		: "r"(&v->counter), "r"(i)				\
+		: "cc", "memory");					\
+}
+
+/* Atomically perform op with v->counter and i, return the result */
+#define ATOMIC_OP_RETURN(op)						\
+static inline int arch_atomic_##op##_return(int i, atomic_t *v)		\
+{									\
+	int tmp;							\
+									\
+	__asm__ __volatile__(						\
+		"1:	l.lwa	%0,0(%1)	\n"			\
+		"	l." #op " %0,%0,%2	\n"			\
+		"	l.swa	0(%1),%0	\n"			\
+		"	l.bnf	1b		\n"			\
+		"	 l.nop			\n"			\
+		: "=&r"(tmp)						\
+		: "r"(&v->counter), "r"(i)				\
+		: "cc", "memory");					\
+									\
+	return tmp;							\
+}
+
+/* Atomically perform op with v->counter and i, return orig v->counter */
+#define ATOMIC_FETCH_OP(op)						\
+static inline int arch_atomic_fetch_##op(int i, atomic_t *v)		\
+{									\
+	int tmp, old;							\
+									\
+	__asm__ __volatile__(						\
+		"1:	l.lwa	%0,0(%2)	\n"			\
+		"	l." #op " %1,%0,%3	\n"			\
+		"	l.swa	0(%2),%1	\n"			\
+		"	l.bnf	1b		\n"			\
+		"	 l.nop			\n"			\
+		: "=&r"(old), "=&r"(tmp)				\
+		: "r"(&v->counter), "r"(i)				\
+		: "cc", "memory");					\
+									\
+	return old;							\
+}
+
+ATOMIC_OP_RETURN(add)
+ATOMIC_OP_RETURN(sub)
+
+ATOMIC_FETCH_OP(add)
+ATOMIC_FETCH_OP(sub)
+ATOMIC_FETCH_OP(and)
+ATOMIC_FETCH_OP(or)
+ATOMIC_FETCH_OP(xor)
+
+ATOMIC_OP(add)
+ATOMIC_OP(sub)
+ATOMIC_OP(and)
+ATOMIC_OP(or)
+ATOMIC_OP(xor)
+
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#define arch_atomic_add_return	arch_atomic_add_return
+#define arch_atomic_sub_return	arch_atomic_sub_return
+#define arch_atomic_fetch_add	arch_atomic_fetch_add
+#define arch_atomic_fetch_sub	arch_atomic_fetch_sub
+#define arch_atomic_fetch_and	arch_atomic_fetch_and
+#define arch_atomic_fetch_or	arch_atomic_fetch_or
+#define arch_atomic_fetch_xor	arch_atomic_fetch_xor
+#define arch_atomic_add		arch_atomic_add
+#define arch_atomic_sub		arch_atomic_sub
+#define arch_atomic_and		arch_atomic_and
+#define arch_atomic_or		arch_atomic_or
+#define arch_atomic_xor		arch_atomic_xor
+
+/*
+ * Atomically add a to v->counter as long as v is not already u.
+ * Returns the original value at v->counter.
+ *
+ * This is often used through atomic_inc_not_zero()
+ */
+static inline int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
+{
+	int old, tmp;
+
+	__asm__ __volatile__(
+		"1:	l.lwa %0, 0(%2)		\n"
+		"	l.sfeq %0, %4		\n"
+		"	l.bf 2f			\n"
+		"	 l.add %1, %0, %3	\n"
+		"	l.swa 0(%2), %1		\n"
+		"	l.bnf 1b		\n"
+		"	 l.nop			\n"
+		"2:				\n"
+		: "=&r"(old), "=&r" (tmp)
+		: "r"(&v->counter), "r"(a), "r"(u)
+		: "cc", "memory");
+
+	return old;
+}
+#define arch_atomic_fetch_add_unless	arch_atomic_fetch_add_unless
+
+#define arch_atomic_read(v)		READ_ONCE((v)->counter)
+#define arch_atomic_set(v,i)		WRITE_ONCE((v)->counter, (i))
+
+#include <asm/cmpxchg.h>
+
+#define arch_atomic_xchg(ptr, v)		(arch_xchg(&(ptr)->counter, (v)))
+#define arch_atomic_cmpxchg(v, old, new)	(arch_cmpxchg(&((v)->counter), (old), (new)))
+
+#endif /* __ASM_OPENRISC_ATOMIC_H */