diff --git a/arch/arm/boot/dts/stih407-b2120.dts b/arch/arm/boot/dts/stih407-b2120.dts
index a3ad52b8de1c8f7ff0593cf191404662f9b8072f..261d5e2c48d24de2262d2947387e39441c6a434d 100644
--- a/arch/arm/boot/dts/stih407-b2120.dts
+++ b/arch/arm/boot/dts/stih407-b2120.dts
@@ -15,7 +15,7 @@
 	compatible = "st,stih407-b2120", "st,stih407";
 
 	chosen {
-		bootargs = "console=ttyAS0,115200";
+		bootargs = "console=ttyAS0,115200 clk_ignore_unused";
 		linux,stdout-path = &sbc_serial0;
 	};
 
diff --git a/arch/arm/boot/dts/stih410-b2120.dts b/arch/arm/boot/dts/stih410-b2120.dts
index 972c17ad8313d0c3bab48a1aad37d7dc5da7332e..2f61a9960dee60d129c7f6c4f84213769cc2856a 100644
--- a/arch/arm/boot/dts/stih410-b2120.dts
+++ b/arch/arm/boot/dts/stih410-b2120.dts
@@ -14,7 +14,7 @@
 	compatible = "st,stih410-b2120", "st,stih410";
 
 	chosen {
-		bootargs = "console=ttyAS0,115200";
+		bootargs = "console=ttyAS0,115200 clk_ignore_unused";
 		linux,stdout-path = &sbc_serial0;
 	};