diff --git a/arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts b/arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts
index 7417cf5fea0f0..2426e533128ce 100644
--- a/arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts
+++ b/arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts
@@ -59,7 +59,7 @@
 	memory@48000000 {
 		device_type = "memory";
 		/* first 128MB is reserved for secure area. */
-		reg = <0x0 0x48000000 0x0 0x38000000>;
+		reg = <0x0 0x48000000 0x0 0x78000000>;
 	};
 
 	osc5_clk: osc5-clock {