Disintegrate asm/system.h for MN10300

Disintegrate asm/system.h for MN10300.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-am33-list@redhat.com
diff --git a/arch/mn10300/include/asm/barrier.h b/arch/mn10300/include/asm/barrier.h
new file mode 100644
index 0000000..2bd97a5
--- /dev/null
+++ b/arch/mn10300/include/asm/barrier.h
@@ -0,0 +1,37 @@
+/* MN10300 memory barrier definitions
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#ifndef _ASM_BARRIER_H
+#define _ASM_BARRIER_H
+
+#define nop()	asm volatile ("nop")
+
+#define mb()	asm volatile ("": : :"memory")
+#define rmb()	mb()
+#define wmb()	asm volatile ("": : :"memory")
+
+#ifdef CONFIG_SMP
+#define smp_mb()	mb()
+#define smp_rmb()	rmb()
+#define smp_wmb()	wmb()
+#define set_mb(var, value)  do { xchg(&var, value); } while (0)
+#else  /* CONFIG_SMP */
+#define smp_mb()	barrier()
+#define smp_rmb()	barrier()
+#define smp_wmb()	barrier()
+#define set_mb(var, value)  do { var = value;  mb(); } while (0)
+#endif /* CONFIG_SMP */
+
+#define set_wmb(var, value) do { var = value; wmb(); } while (0)
+
+#define read_barrier_depends()		do {} while (0)
+#define smp_read_barrier_depends()	do {} while (0)
+
+#endif /* _ASM_BARRIER_H */