diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 4846946..fc21329 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -1124,9 +1124,8 @@
 	RFI
 
 /*
- * Use the first pair of BAT registers to map the 1st 16MB
- * of RAM to PAGE_OFFSET.  From this point on we can't safely
- * call OF any more.
+ * On 601, we use 3 BATs to map up to 24M of RAM at _PAGE_OFFSET
+ * (we keep one for debugging) and on others, we use one 256M BAT.
  */
 initial_bats:
 	lis	r11,PAGE_OFFSET@h
@@ -1136,12 +1135,16 @@
 	bne	4f
 	ori	r11,r11,4		/* set up BAT registers for 601 */
 	li	r8,0x7f			/* valid, block length = 8MB */
-	oris	r9,r11,0x800000@h	/* set up BAT reg for 2nd 8M */
-	oris	r10,r8,0x800000@h	/* set up BAT reg for 2nd 8M */
 	mtspr	SPRN_IBAT0U,r11		/* N.B. 601 has valid bit in */
 	mtspr	SPRN_IBAT0L,r8		/* lower BAT register */
-	mtspr	SPRN_IBAT1U,r9
-	mtspr	SPRN_IBAT1L,r10
+	addis	r11,r11,0x800000@h
+	addis	r8,r8,0x800000@h
+	mtspr	SPRN_IBAT1U,r11
+	mtspr	SPRN_IBAT1L,r8
+	addis	r11,r11,0x800000@h
+	addis	r8,r8,0x800000@h
+	mtspr	SPRN_IBAT2U,r11
+	mtspr	SPRN_IBAT2L,r8
 	isync
 	blr