Index: linux-2.6.25.1/arch/mips/mm/init.c
===================================================================
--- linux-2.6.25.1.orig/arch/mips/mm/init.c	2008-05-18 11:32:33.000000000 +0100
+++ linux-2.6.25.1/arch/mips/mm/init.c	2008-05-18 21:05:57.000000000 +0100
@@ -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 &&
+	if (cpu_has_dc_aliases && cpu_use_kmap_coherent &&
 	    page_mapped(from) && !Page_dcache_dirty(from)) {
 		vfrom = kmap_coherent(from, vaddr);
 		copy_page(vto, vfrom);
@@ -235,7 +235,7 @@ 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 &&
 	    page_mapped(page) && !Page_dcache_dirty(page)) {
 		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(vto, src, len);
@@ -255,7 +255,7 @@ 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 &&
 	    page_mapped(page) && !Page_dcache_dirty(page)) {
 		void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(dst, vfrom, len);
Index: linux-2.6.25.1/include/asm-mips/mach-bcm47xx/cpu-feature-overrides.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.25.1/include/asm-mips/mach-bcm47xx/cpu-feature-overrides.h	2008-05-18 11:32:40.000000000 +0100
@@ -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_BCM47XX_CPU_FEATURE_OVERRIDES_H
+#define __ASM_MACH_BCM47XX_CPU_FEATURE_OVERRIDES_H
+
+#define cpu_use_kmap_coherent	0
+
+#endif /* __ASM_MACH_BCM47XX_CPU_FEATURE_OVERRIDES_H */
Index: linux-2.6.25.1/include/asm-mips/cpu-features.h
===================================================================
--- linux-2.6.25.1.orig/include/asm-mips/cpu-features.h	2008-05-18 11:32:33.000000000 +0100
+++ linux-2.6.25.1/include/asm-mips/cpu-features.h	2008-05-18 11:32:40.000000000 +0100
@@ -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
Index: linux-2.6.25.1/arch/mips/mm/c-r4k.c
===================================================================
--- linux-2.6.25.1.orig/arch/mips/mm/c-r4k.c	2008-05-18 21:06:36.000000000 +0100
+++ linux-2.6.25.1/arch/mips/mm/c-r4k.c	2008-05-18 21:09:28.000000000 +0100
@@ -484,7 +484,7 @@ static inline void local_r4k_flush_cache
 		 * Use kmap_coherent or kmap_atomic to do flushes for
 		 * another ASID than the current one.
 		 */
-		if (cpu_has_dc_aliases)
+		if (cpu_has_dc_aliases && cpu_use_kmap_coherent)
 			vaddr = kmap_coherent(page, addr);
 		else
 			vaddr = kmap_atomic(page, KM_USER0);
@@ -505,7 +505,7 @@ static inline void local_r4k_flush_cache
 	}
 
 	if (vaddr) {
-		if (cpu_has_dc_aliases)
+		if (cpu_has_dc_aliases && cpu_use_kmap_coherent)
 			kunmap_coherent();
 		else
 			kunmap_atomic(vaddr, KM_USER0);