diff --git a/arch/powerpc/cpu/mpc85xx/mp.c b/arch/powerpc/cpu/mpc85xx/mp.c
index 6c0da83176e8683516945a1cdf9e61b3c513a03f..758e6d7045f8ffe1da4f6b4ce2eb6027975689ce 100644
--- a/arch/powerpc/cpu/mpc85xx/mp.c
+++ b/arch/powerpc/cpu/mpc85xx/mp.c
@@ -276,8 +276,13 @@ static void plat_mp_up(unsigned long bootpg)
 
 	/* enable time base at the platform */
 	out_be32(&rcpm->ctbenrl, 0);
+
+	/* readback to sync write */
+	in_be32(&rcpm->ctbenrl);
+
 	mtspr(SPRN_TBWU, 0);
 	mtspr(SPRN_TBWL, 0);
+
 	out_be32(&rcpm->ctbenrl, (1 << nr_cpus) - 1);
 
 #ifdef CONFIG_MPC8xxx_DISABLE_BPTR
@@ -347,6 +352,10 @@ static void plat_mp_up(unsigned long bootpg)
 	else
 		devdisr |= MPC85xx_DEVDISR_TB0;
 	out_be32(&gur->devdisr, devdisr);
+
+	/* readback to sync write */
+	in_be32(&gur->devdisr);
+
 	mtspr(SPRN_TBWU, 0);
 	mtspr(SPRN_TBWL, 0);