Initial import

1 files changed, 66 insertions, 0 deletions

diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h
new file mode 100644
index 000000000..05b9f74ce
--- /dev/null
+++ b/arch/sh/include/asm/atomic.h
@@ -0,0 +1,66 @@
+#ifndef __ASM_SH_ATOMIC_H
+#define __ASM_SH_ATOMIC_H
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ *
+ */
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+#define ATOMIC_INIT(i)	{ (i) }
+
+#define atomic_read(v)		ACCESS_ONCE((v)->counter)
+#define atomic_set(v,i)		((v)->counter = (i))
+
+#if defined(CONFIG_GUSA_RB)
+#include <asm/atomic-grb.h>
+#elif defined(CONFIG_CPU_SH4A)
+#include <asm/atomic-llsc.h>
+#else
+#include <asm/atomic-irq.h>
+#endif
+
+#define atomic_add_negative(a, v)	(atomic_add_return((a), (v)) < 0)
+#define atomic_dec_return(v)		atomic_sub_return(1, (v))
+#define atomic_inc_return(v)		atomic_add_return(1, (v))
+#define atomic_inc_and_test(v)		(atomic_inc_return(v) == 0)
+#define atomic_sub_and_test(i,v)	(atomic_sub_return((i), (v)) == 0)
+#define atomic_dec_and_test(v)		(atomic_sub_return(1, (v)) == 0)
+
+#define atomic_inc(v)			atomic_add(1, (v))
+#define atomic_dec(v)			atomic_sub(1, (v))
+
+#define atomic_xchg(v, new)		(xchg(&((v)->counter), new))
+#define atomic_cmpxchg(v, o, n)		(cmpxchg(&((v)->counter), (o), (n)))
+
+/**
+ * __atomic_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns the old value of @v.
+ */
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+	int c, old;
+	c = atomic_read(v);
+	for (;;) {
+		if (unlikely(c == (u)))
+			break;
+		old = atomic_cmpxchg((v), c, c + (a));
+		if (likely(old == c))
+			break;
+		c = old;
+	}
+
+	return c;
+}
+
+#endif /* __ASM_SH_ATOMIC_H */