Enable write buffer coalescing

svn path=/dists/trunk/linux-2.6/; revision=10908

debian/changelog

@@ -50,6 +50,7 @@ linux-2.6 (2.6.25~rc6-1~experimental.1) UNRELEASED; urgency=low
   * [mips/r5k-ip32] Use the generic config options for NFS, which will
     enable NFSv4. (closes: #471007)
   * [mips/r5k-ip32] Enable R8169, requested by Giuseppe Sacco.
+  * [arm/iop32x] Enable write buffer coalescing (Arnaud Patard).
 
   [ Daniel Baumann ]
   * Added patch from unionfs upstream to export release_open_intent symbol.

debian/patches/bugfix/arm/enable_wb_coal.patch

@@ -0,0 +1,31 @@
+From: Arnaud Patard <arnaud.patard@rtp-net.org>
+
+[PATCH] Enable write buffer coalescing
+
+RedBoot is disabling write buffer coalescing before giving the hand to
+linux. As there's no place in the kernel reenabling it, the performances
+are poor (see
+http://lists.arm.linux.org.uk/lurker/message/20080308.225920.2ae2af55.en.html).
+This patch reenable it.
+
+Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
+
+---
+ arch/arm/mm/proc-xscale.S |    4 	4 +	0 -	0 !
+ 1 file changed, 4 insertions(+)
+
+Index: linux-2.6/arch/arm/mm/proc-xscale.S
+===================================================================
+--- linux-2.6.orig/arch/arm/mm/proc-xscale.S	2008-03-09 00:37:05.000000000 +0100
++++ linux-2.6/arch/arm/mm/proc-xscale.S	2008-03-09 12:27:50.000000000 +0100
+@@ -114,6 +114,10 @@ clean_addr:	.word	CLEAN_ADDR
+  * Nothing too exciting at the moment
+  */
+ ENTRY(cpu_xscale_proc_init)
++	@ enable write buffer coalescing. Some bootloader disable it
++	mrc	p15, 0, r1, c1, c0, 1
++	bic	r1, r1, #1
++	mcr	p15, 0, r1, c1, c0, 1
+ 	mov	pc, lr
+ 
+ /*