sh: migrate to arch/sh/include/
[pandora-kernel.git] / arch / sh / include / asm / atomic.h
diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h
new file mode 100644 (file)
index 0000000..c043ef0
--- /dev/null
@@ -0,0 +1,89 @@
+#ifndef __ASM_SH_ATOMIC_H
+#define __ASM_SH_ATOMIC_H
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ *
+ */
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
+
+#define atomic_read(v)         ((v)->counter)
+#define atomic_set(v,i)                ((v)->counter = (i))
+
+#include <linux/compiler.h>
+#include <asm/system.h>
+
+#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))
+
+/*
+ * atomic_inc_and_test - increment and test
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+#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))
+
+#ifndef CONFIG_GUSA_RB
+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 ret;
+       unsigned long flags;
+
+       local_irq_save(flags);
+       ret = v->counter;
+       if (ret != u)
+               v->counter += a;
+       local_irq_restore(flags);
+
+       return ret != u;
+}
+#endif
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+/* Atomic operations are already serializing on SH */
+#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_SH_ATOMIC_H */