Index: linux-2.6.23.17/arch/mips/mm/init.c
===================================================================
--- linux-2.6.23.17.orig/arch/mips/mm/init.c
+++ linux-2.6.23.17/arch/mips/mm/init.c
@@ -211,7 +211,7 @@ void copy_user_highpage(struct page *to,
 	void *vfrom, *vto;
 
 	vto = kmap_atomic(to, KM_USER1);
-	if (cpu_has_dc_aliases && !Page_dcache_dirty(from)) {
+	if (cpu_has_dc_aliases && cpu_use_kmap_coherent && !Page_dcache_dirty(from)) {
 		vfrom = kmap_coherent(from, vaddr);
 		copy_page(vto, vfrom);
 		kunmap_coherent();
@@ -234,7 +234,7 @@ void copy_to_user_page(struct vm_area_st
 	struct page *page, unsigned long vaddr, void *dst, const void *src,
 	unsigned long len)
 {
-	if (cpu_has_dc_aliases) {
+	if (cpu_has_dc_aliases && cpu_use_kmap_coherent) {
 		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(vto, src, len);
 		kunmap_coherent();
@@ -250,7 +250,7 @@ void copy_from_user_page(struct vm_area_
 	struct page *page, unsigned long vaddr, void *dst, const void *src,
 	unsigned long len)
 {
-	if (cpu_has_dc_aliases) {
+	if (cpu_has_dc_aliases && cpu_use_kmap_coherent) {
 		void *vfrom =
 			kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(dst, vfrom, len);
Index: linux-2.6.23.17/include/asm-mips/mach-bcm947xx/cpu-feature-overrides.h
===================================================================
--- /dev/null
+++ linux-2.6.23.17/include/asm-mips/mach-bcm947xx/cpu-feature-overrides.h
@@ -0,0 +1,13 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
+ */
+#ifndef __ASM_MACH_BCM947XX_CPU_FEATURE_OVERRIDES_H
+#define __ASM_MACH_BCM947XX_CPU_FEATURE_OVERRIDES_H
+
+#define cpu_use_kmap_coherent	0
+
+#endif /* __ASM_MACH_BCM947XX_CPU_FEATURE_OVERRIDES_H */
Index: linux-2.6.23.17/include/asm-mips/cpu-features.h
===================================================================
--- linux-2.6.23.17.orig/include/asm-mips/cpu-features.h
+++ linux-2.6.23.17/include/asm-mips/cpu-features.h
@@ -101,6 +101,9 @@
 #ifndef cpu_has_pindexed_dcache
 #define cpu_has_pindexed_dcache	(cpu_data[0].dcache.flags & MIPS_CACHE_PINDEX)
 #endif
+#ifndef cpu_use_kmap_coherent
+#define cpu_use_kmap_coherent 1
+#endif
 
 /*
  * I-Cache snoops remote store.  This only matters on SMP.  Some multiprocessors