diff --git a/drivers/cpufreq/imx-cpufreq-dt.c b/drivers/cpufreq/imx-cpufreq-dt.c
index 4f85f3112784..35db14cf3102 100644
--- a/drivers/cpufreq/imx-cpufreq-dt.c
+++ b/drivers/cpufreq/imx-cpufreq-dt.c
@@ -16,6 +16,7 @@
 
 #define OCOTP_CFG3_SPEED_GRADE_SHIFT	8
 #define OCOTP_CFG3_SPEED_GRADE_MASK	(0x3 << 8)
+#define IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK	(0xf << 8)
 #define OCOTP_CFG3_MKT_SEGMENT_SHIFT    6
 #define OCOTP_CFG3_MKT_SEGMENT_MASK     (0x3 << 6)
 
@@ -34,7 +35,12 @@ static int imx_cpufreq_dt_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK) >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
+	if (of_machine_is_compatible("fsl,imx8mn"))
+		speed_grade = (cell_value & IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK)
+			      >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
+	else
+		speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK)
+			      >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
 	mkt_segment = (cell_value & OCOTP_CFG3_MKT_SEGMENT_MASK) >> OCOTP_CFG3_MKT_SEGMENT_SHIFT;
 
 	/*