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-rw-r--r--arch/microblaze/include/asm/atomic.h123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/atomic.h b/arch/microblaze/include/asm/atomic.h
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+++ b/arch/microblaze/include/asm/atomic.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_MICROBLAZE_ATOMIC_H
+#define _ASM_MICROBLAZE_ATOMIC_H
+
+#include <linux/types.h>
+#include <linux/compiler.h> /* likely */
+#include <asm/system.h> /* local_irq_XXX and friends */
+
+#define ATOMIC_INIT(i)		{ (i) }
+#define atomic_read(v)		((v)->counter)
+#define atomic_set(v, i)	(((v)->counter) = (i))
+
+#define atomic_inc(v)		(atomic_add_return(1, (v)))
+#define atomic_dec(v)		(atomic_sub_return(1, (v)))
+
+#define atomic_add(i, v)	(atomic_add_return(i, (v)))
+#define atomic_sub(i, v)	(atomic_sub_return(i, (v)))
+
+#define atomic_inc_return(v)	(atomic_add_return(1, (v)))
+#define atomic_dec_return(v)	(atomic_sub_return(1, (v)))
+
+#define atomic_inc_and_test(v)	(atomic_add_return(1, (v)) == 0)
+#define atomic_dec_and_test(v)	(atomic_sub_return(1, (v)) == 0)
+
+#define atomic_inc_not_zero(v)	(atomic_add_unless((v), 1, 0))
+
+#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+	int ret;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	ret = v->counter;
+	if (likely(ret == old))
+		v->counter = new;
+	local_irq_restore(flags);
+
+	return ret;
+}
+
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+	int c, old;
+
+	c = atomic_read(v);
+	while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
+		c = old;
+	return c != u;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	*addr &= ~mask;
+	local_irq_restore(flags);
+}
+
+/**
+ * atomic_add_return - add and return
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v and returns @i + @v
+ */
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+	unsigned long flags;
+	int val;
+
+	local_irq_save(flags);
+	val = v->counter;
+	v->counter = val += i;
+	local_irq_restore(flags);
+
+	return val;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+	return atomic_add_return(-i, v);
+}
+
+/*
+ * Atomically test *v and decrement if it is greater than 0.
+ * The function returns the old value of *v minus 1.
+ */
+static inline int atomic_dec_if_positive(atomic_t *v)
+{
+	unsigned long flags;
+	int res;
+
+	local_irq_save(flags);
+	res = v->counter - 1;
+	if (res >= 0)
+		v->counter = res;
+	local_irq_restore(flags);
+
+	return res;
+}
+
+#define atomic_add_negative(a, v)	(atomic_add_return((a), (v)) < 0)
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+/* Atomic operations are already serializing */
+#define smp_mb__before_atomic_dec()	barrier()
+#define smp_mb__after_atomic_dec()	barrier()
+#define smp_mb__before_atomic_inc()	barrier()
+#define smp_mb__after_atomic_inc()	barrier()
+
+#include <asm-generic/atomic.h>
+
+#endif /* _ASM_MICROBLAZE_ATOMIC_H */