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-rw-r--r--arch/openrisc/include/asm/atomic.h126
1 files changed, 126 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..b589fac39
--- /dev/null
+++ b/arch/openrisc/include/asm/atomic.h
@@ -0,0 +1,126 @@
+/*
+ * 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 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 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 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(and)
+ATOMIC_OP(or)
+ATOMIC_OP(xor)
+
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+#define atomic_add_return atomic_add_return
+#define atomic_sub_return atomic_sub_return
+#define atomic_fetch_add atomic_fetch_add
+#define atomic_fetch_sub atomic_fetch_sub
+#define atomic_fetch_and atomic_fetch_and
+#define atomic_fetch_or atomic_fetch_or
+#define atomic_fetch_xor atomic_fetch_xor
+#define atomic_and atomic_and
+#define atomic_or atomic_or
+#define atomic_xor 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 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 atomic_fetch_add_unless atomic_fetch_add_unless
+
+#include <asm-generic/atomic.h>
+
+#endif /* __ASM_OPENRISC_ATOMIC_H */