ppc4xx: Rework 4xx cache support

New cache handling functions added and all existing functions
moved from start.S into seperate cache.S.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/include/ppc405.h b/include/ppc405.h
index 97528e8..2c55917 100644
--- a/include/ppc405.h
+++ b/include/ppc405.h
@@ -22,6 +22,12 @@
 #ifndef	__PPC405_H__
 #define __PPC405_H__
 
+#ifndef CONFIG_IOP480
+#define CFG_DCACHE_SIZE		(16 << 10)	/* For AMCC 405 CPUs	*/
+#else
+#define CFG_DCACHE_SIZE		(2 << 10)	/* For PLX IOP480 (403)	*/
+#endif
+
 /*--------------------------------------------------------------------- */
 /* Special Purpose Registers						*/
 /*--------------------------------------------------------------------- */