MN10300: Cache: Implement SMP global cache flushing

Implement SMP global cache flushing for MN10300.  This will be used by the AM34
which is SMP capable.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/arch/mn10300/mm/Kconfig.cache b/arch/mn10300/mm/Kconfig.cache
index 653254a..c4fd923 100644
--- a/arch/mn10300/mm/Kconfig.cache
+++ b/arch/mn10300/mm/Kconfig.cache
@@ -60,6 +60,7 @@
 
 config MN10300_CACHE_MANAGE_BY_TAG
 	bool "Use the cache tag registers directly"
+	depends on !(SMP && MN10300_CACHE_WTHRU)
 
 config MN10300_CACHE_MANAGE_BY_REG
 	bool "Flush areas by way of automatic purge registers (AM34 only)"