--- zzzz-none-000/linux-2.6.13.1/include/asm-mips/page.h	2005-09-10 02:42:58.000000000 +0000
+++ ohio-7170-487/linux-2.6.13.1/include/asm-mips/page.h	2006-11-06 16:02:03.000000000 +0000
@@ -130,7 +130,15 @@
 #ifndef CONFIG_NEED_MULTIPLE_NODES
 #define pfn_to_page(pfn)	(mem_map + (pfn))
 #define page_to_pfn(page)	((unsigned long)((page) - mem_map))
+#ifdef CONFIG_MIPS_OHIO
+#define pfn_valid(pfn)		(((pfn) < max_mapnr) && ((pfn) >= (CONFIG_MIPS_OHIO_PHY_MEMSTART >> PAGE_SHIFT)))
+#elif CONFIG_MIPS_AR7
+#define pfn_valid(pfn)		(((pfn) < max_mapnr) && ((pfn) >= (CONFIG_MIPS_AR7_PHY_MEMSTART >> PAGE_SHIFT)))
+#elif CONFIG_MIPS_UR8
+#define pfn_valid(pfn)		(((pfn) < max_mapnr) && ((pfn) >= (CONFIG_MIPS_UR8_PHY_MEMSTART >> PAGE_SHIFT)))
+#else /*--- #ifdef CONFIG_MIPS_OHIO ---*/
 #define pfn_valid(pfn)		((pfn) < max_mapnr)
+#endif /*--- #else ---*/ /*--- #ifdef CONFIG_MIPS_OHIO ---*/
 #endif
 
 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)