diff --git a/src/mainboard/intel/shadowmountain/variants/baseboard/devicetree.cb b/src/mainboard/intel/shadowmountain/variants/baseboard/devicetree.cb
index d5e5951c2a..ab2c915488 100644
--- a/src/mainboard/intel/shadowmountain/variants/baseboard/devicetree.cb
+++ b/src/mainboard/intel/shadowmountain/variants/baseboard/devicetree.cb
@@ -103,7 +103,7 @@ chip soc/intel/alderlake
 	}"
 
 	register "SerialIoUartMode" = "{
-		[PchSerialIoIndexUART0] = PchSerialIoPci,
+		[PchSerialIoIndexUART0] = PchSerialIoSkipInit,
 		[PchSerialIoIndexUART1] = PchSerialIoDisabled,
 		[PchSerialIoIndexUART2] = PchSerialIoDisabled,
 	}"