arm64: dts: mediatek: mt7981: add UART controllers

MT7981 has three on-SoC UART controllers.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240727121447.1016-2-zajec5@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm64/boot/dts/mediatek/mt7981b.dtsi

@@ -94,6 +94,39 @@ pwm@10048000 {
 			#pwm-cells = <2>;
 		};
 
+		serial@11002000 {
+			compatible = "mediatek,mt7981-uart", "mediatek,mt6577-uart";
+			reg = <0 0x11002000 0 0x100>;
+			interrupts = <GIC_SPI 123 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "uart", "wakeup";
+			clocks = <&infracfg CLK_INFRA_UART0_SEL>,
+				 <&infracfg CLK_INFRA_UART0_CK>;
+			clock-names = "baud", "bus";
+			status = "disabled";
+		};
+
+		serial@11003000 {
+			compatible = "mediatek,mt7981-uart", "mediatek,mt6577-uart";
+			reg = <0 0x11003000 0 0x100>;
+			interrupts = <GIC_SPI 124 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "uart", "wakeup";
+			clocks = <&infracfg CLK_INFRA_UART1_SEL>,
+				 <&infracfg CLK_INFRA_UART1_CK>;
+			clock-names = "baud", "bus";
+			status = "disabled";
+		};
+
+		serial@11004000 {
+			compatible = "mediatek,mt7981-uart", "mediatek,mt6577-uart";
+			reg = <0 0x11004000 0 0x100>;
+			interrupts = <GIC_SPI 125 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "uart", "wakeup";
+			clocks = <&infracfg CLK_INFRA_UART2_SEL>,
+				 <&infracfg CLK_INFRA_UART2_CK>;
+			clock-names = "baud", "bus";
+			status = "disabled";
+		};
+
 		i2c@11007000 {
 			compatible = "mediatek,mt7981-i2c";
 			reg = <0 0x11007000 0 0x1000>,