Subject: [PATCH] powerpc: Always use -mno-string

From: Benjamin Herrenschmidt <[email-masked]>
Date: Thu, 22 Mar 2007 17:23:44 +1100

The string load/store instructions are causing more damage than
help on a lot of processors where they are microcoded and are
generally not good for the kernel to use. Let's make sure we
don't emit them on any powerpc variant.

Signed-off-by: Benjamin Herrenschmidt <[email-masked]>
---

Ok, let's keep load/store multiple, they are only used on 32 bits
and are actually useful. string instructions are not though.

Index: linux-cell/arch/powerpc/Makefile
===================================================================
--- linux-cell.orig/arch/powerpc/Makefile	2007-03-22 17:02:42.000000000 +1100
+++ linux-cell/arch/powerpc/Makefile	2007-03-22 17:19:28.000000000 +1100
@@ -102,9 +102,9 @@ CFLAGS += $(call cc-option,-mno-altivec)
 # kernel considerably.
 CFLAGS += $(call cc-option,-funit-at-a-time)
 
-ifndef CONFIG_FSL_BOOKE
-CFLAGS		+= -mstring
-endif
+# Never use string load/store instructions as they are
+# often slow when they are implemented at all
+CFLAGS		+= -mno-string
 
 ifeq ($(CONFIG_6xx),y)
 CFLAGS		+= -mcpu=powerpc