Blackfin arch: rewrite blackfin_invalidate_entire_dcache function

rewrite blackfin_invalidate_entire_dcache() in C for easier management,
better optimization, and so we take all SSYNC anomalies into account

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

arch/blackfin/mach-common/cache-c.c

@@ -0,0 +1,24 @@
+/*
+ * Blackfin cache control code (simpler control-style functions)
+ *
+ * Copyright 2004-2008 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <asm/blackfin.h>
+
+/* Invalidate the Entire Data cache by
+ * clearing DMC[1:0] bits
+ */
+void blackfin_invalidate_entire_dcache(void)
+{
+	u32 dmem = bfin_read_DMEM_CONTROL();
+	SSYNC();
+	bfin_write_DMEM_CONTROL(dmem & ~0xc);
+	SSYNC();
+	bfin_write_DMEM_CONTROL(dmem);
+	SSYNC();
+}