sh: Add sys_cacheflush() call for SH CPUs.

Adds a system call to allow user code to flush code from the cache.
You can use instructions for the data side, but the iside can
only be done by a flush ROM which really only works with a direct
mapped cache. The later SH4's have 2 way Iside, so this call allows
a portable way to flush the cache.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/cachectl.h b/arch/sh/include/asm/cachectl.h
new file mode 100644
index 0000000..305dd70
--- /dev/null
+++ b/arch/sh/include/asm/cachectl.h
@@ -0,0 +1,12 @@
+#ifndef _SH_CACHECTL_H
+#define _SH_CACHECTL_H
+
+/* Definitions for the cacheflush system call.  */
+
+#define CACHEFLUSH_D_INVAL	0x1	/* invalidate (without write back) */
+#define CACHEFLUSH_D_WB		0x2	/* write back (without invalidate) */
+#define CACHEFLUSH_D_PURGE	0x3	/* writeback and invalidate */
+
+#define CACHEFLUSH_I		0x4
+
+#endif /* _SH_CACHECTL_H */