diff --git a/target/linux/ramips/dts/R6220.dts b/target/linux/ramips/dts/R6220.dts
index 72c6fc7d5a..eb9f3c4a25 100644
--- a/target/linux/ramips/dts/R6220.dts
+++ b/target/linux/ramips/dts/R6220.dts
@@ -117,6 +117,7 @@
 	partition@4200000 {
 		label = "reserved";
 		reg = <0x4200000 0x3c00000>;
+		read-only;
 	};
 };