diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index b4bcf5a930fafd50a350d6e97bf8cf8cde833764..ebaedafc8e67403efe716703d6110825d589a77d 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -1518,6 +1518,15 @@ _GLOBAL(pmac_secondary_start)
 	/* turn on 64-bit mode */
 	bl	.enable_64b_mode
 
+	li	r0,0
+	mfspr	r3,SPRN_HID4
+	rldimi	r3,r0,40,23	/* clear bit 23 (rm_ci) */
+	sync
+	mtspr	SPRN_HID4,r3
+	isync
+	sync
+	slbia
+
 	/* get TOC pointer (real address) */
 	bl	.relative_toc
 
diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index 6b0711c15ecaf9ad506e6b9dfd8eec61677dd978..bd8817b00fa4a80f3d2ab4649e6ef917ec9db8aa 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -53,7 +53,7 @@
 #include <asm/pmac_low_i2c.h>
 #include <asm/pmac_pfunc.h>
 
-#define DEBUG
+#undef DEBUG
 
 #ifdef DEBUG
 #define DBG(fmt...) udbg_printf(fmt)