diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index b07c799f72f2..091d7fb6ee7d 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -702,7 +702,7 @@ scifa5: serial@e6c80000 {
 	scifb0: serial@e6c20000 {
 		compatible = "renesas,scifb-r8a7791",
 			     "renesas,rcar-gen2-scifb", "renesas,scifb";
-		reg = <0 0xe6c20000 0 64>;
+		reg = <0 0xe6c20000 0 0x100>;
 		interrupts = <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&mstp2_clks R8A7791_CLK_SCIFB0>;
 		clock-names = "fck";
@@ -716,7 +716,7 @@ scifb0: serial@e6c20000 {
 	scifb1: serial@e6c30000 {
 		compatible = "renesas,scifb-r8a7791",
 			     "renesas,rcar-gen2-scifb", "renesas,scifb";
-		reg = <0 0xe6c30000 0 64>;
+		reg = <0 0xe6c30000 0 0x100>;
 		interrupts = <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&mstp2_clks R8A7791_CLK_SCIFB1>;
 		clock-names = "fck";
@@ -730,7 +730,7 @@ scifb1: serial@e6c30000 {
 	scifb2: serial@e6ce0000 {
 		compatible = "renesas,scifb-r8a7791",
 			     "renesas,rcar-gen2-scifb", "renesas,scifb";
-		reg = <0 0xe6ce0000 0 64>;
+		reg = <0 0xe6ce0000 0 0x100>;
 		interrupts = <GIC_SPI 150 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&mstp2_clks R8A7791_CLK_SCIFB2>;
 		clock-names = "fck";