diff --git a/arch/arm64/boot/dts/mediatek/mt8195-demo.dts b/arch/arm64/boot/dts/mediatek/mt8195-demo.dts
index 4fbd99eb496a..dec85d254838 100644
--- a/arch/arm64/boot/dts/mediatek/mt8195-demo.dts
+++ b/arch/arm64/boot/dts/mediatek/mt8195-demo.dts
@@ -56,10 +56,10 @@ reserved-memory {
 		#size-cells = <2>;
 		ranges;
 
-		/* 192 KiB reserved for ARM Trusted Firmware (BL31) */
+		/* 2 MiB reserved for ARM Trusted Firmware (BL31) */
 		bl31_secmon_reserved: secmon@54600000 {
 			no-map;
-			reg = <0 0x54600000 0x0 0x30000>;
+			reg = <0 0x54600000 0x0 0x200000>;
 		};
 
 		/* 12 MiB reserved for OP-TEE (BL32)