4 - compatible : "rda,8810pl-uart" for RDA8810PL SoCs.
5 - reg : Offset and length of the register set for the device.
6 - interrupts : Should contain UART interrupt.
7 - clocks : Phandle to the input clock.
12 uart2: serial@20a90000 {
13 compatible = "rda,8810pl-uart";
14 reg = <0x20a90000 0x1000>;
15 interrupts = <11 IRQ_TYPE_LEVEL_HIGH>;