--- a/include/asm-mips/pgtable-32.h	2007-07-19 08:22:43.000000000 +0800
+++ b/include/asm-mips/pgtable-32.h	2007-07-20 11:12:40.000000000 +0800
@@ -46,7 +46,7 @@
 #ifdef CONFIG_64BIT_PHYS_ADDR
 #define PGDIR_SHIFT	21
 #else
-#define PGDIR_SHIFT	22
+#define PGDIR_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 2))
 #endif
 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))