Blackfin: add new cacheflush syscall

Flushing caches sometimes requires anomaly workarounds which require
supervisor-only insns.  Normally we don't need to flush caches from
userspace so this isn't a problem, but when gcc generates trampolines
on the stack, we do.

So add a new syscall for gcc to use modeled after the mips version.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/include/asm/cachectl.h b/arch/blackfin/include/asm/cachectl.h
new file mode 100644
index 0000000..03255df
--- /dev/null
+++ b/arch/blackfin/include/asm/cachectl.h
@@ -0,0 +1,20 @@
+/*
+ * based on the mips/cachectl.h
+ *
+ * Copyright 2010 Analog Devices Inc.
+ * Copyright (C) 1994, 1995, 1996 by Ralf Baechle
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef	_ASM_CACHECTL
+#define	_ASM_CACHECTL
+
+/*
+ * Options for cacheflush system call
+ */
+#define	ICACHE	(1<<0)		/* flush instruction cache        */
+#define	DCACHE	(1<<1)		/* writeback and flush data cache */
+#define	BCACHE	(ICACHE|DCACHE)	/* flush both caches              */
+
+#endif	/* _ASM_CACHECTL */