powerpc: add 2 common dcache assembly functions

This patch defines the 2 flush_dcache_range and invalidate_dcache_range
functions for all the powerpc architecture. Their implementation is
borrowed from the kernel's misc_32.S file and replace the ones from
mpc86xx and ppc4xx since they were equivalent.

This is a fix for the problem introduced by this patch:
http://patchwork.ozlabs.org/patch/448849/

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/arch/powerpc/lib/ppccache.S b/arch/powerpc/lib/ppccache.S
index 349a1c1..b96dbc6 100644
--- a/arch/powerpc/lib/ppccache.S
+++ b/arch/powerpc/lib/ppccache.S
@@ -9,6 +9,9 @@
 
 #include <config.h>
 #include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+
+#include <asm/cache.h>
 
 /*------------------------------------------------------------------------------- */
 /* Function:	 ppcDcbf */
@@ -54,3 +57,48 @@
 ppcSync:
 	sync
 	blr
+
+/*
+ * Write any modified data cache blocks out to memory and invalidate them.
+ * Does not invalidate the corresponding instruction cache blocks.
+ *
+ * flush_dcache_range(unsigned long start, unsigned long stop)
+ */
+_GLOBAL(flush_dcache_range)
+	li	r5,L1_CACHE_BYTES-1
+	andc	r3,r3,r5
+	subf	r4,r3,r4
+	add	r4,r4,r5
+	srwi.	r4,r4,L1_CACHE_SHIFT
+	beqlr
+	mtctr	r4
+
+1:	dcbf	0,r3
+	addi	r3,r3,L1_CACHE_BYTES
+	bdnz	1b
+	sync				/* wait for dcbst's to get to ram */
+	blr
+
+/*
+ * Like above, but invalidate the D-cache.  This is used by the 8xx
+ * to invalidate the cache so the PPC core doesn't get stale data
+ * from the CPM (no cache snooping here :-).
+ *
+ * invalidate_dcache_range(unsigned long start, unsigned long stop)
+ */
+_GLOBAL(invalidate_dcache_range)
+	li	r5,L1_CACHE_BYTES-1
+	andc	r3,r3,r5
+	subf	r4,r3,r4
+	add	r4,r4,r5
+	srwi.	r4,r4,L1_CACHE_SHIFT
+	beqlr
+	mtctr	r4
+
+	sync
+1:	dcbi	0,r3
+	addi	r3,r3,L1_CACHE_BYTES
+	bdnz	1b
+	sync				/* wait for dcbi's to get to ram */
+	blr
+