diff --git a/cpu/mpc85xx/cpu.c b/cpu/mpc85xx/cpu.c
index 67e81c0..f15b0a8 100644
--- a/cpu/mpc85xx/cpu.c
+++ b/cpu/mpc85xx/cpu.c
@@ -85,7 +85,8 @@
 	struct cpu_type *cpu;
 #ifdef CONFIG_DDR_CLK_FREQ
 	volatile ccsr_gur_t *gur = (void *)(CFG_MPC85xx_GUTS_ADDR);
-	u32 ddr_ratio = ((gur->porpllsr) & 0x00003e00) >> 9;
+	u32 ddr_ratio = ((gur->porpllsr) & MPC85xx_PORPLLSR_DDR_RATIO)
+		>> MPC85xx_PORPLLSR_DDR_RATIO_SHIFT;
 #else
 	u32 ddr_ratio = 0;
 #endif
diff --git a/cpu/mpc85xx/speed.c b/cpu/mpc85xx/speed.c
index 1cda1e3..485ba20 100644
--- a/cpu/mpc85xx/speed.c
+++ b/cpu/mpc85xx/speed.c
@@ -54,7 +54,8 @@
 
 #ifdef CONFIG_DDR_CLK_FREQ
 	{
-		u32 ddr_ratio = ((gur->porpllsr) & 0x00003e00) >> 9;
+		u32 ddr_ratio = ((gur->porpllsr) & MPC85xx_PORPLLSR_DDR_RATIO)
+			>> MPC85xx_PORPLLSR_DDR_RATIO_SHIFT;
 		if (ddr_ratio != 0x7)
 			sysInfo->freqDDRBus = ddr_ratio * CONFIG_DDR_CLK_FREQ;
 	}