zephyr/dts/arm/nordic/nrf51822.dtsi

#include <arm/armv6-m.dtsi>
#include <nordic/mem.h>

/ {
	cpus {
		#address-cells = <1>;
		#size-cells = <0>;

		cpu@0 {
			device_type = "cpu";
			compatible = "arm,cortex-m0";
			reg = <0>;
		};
	};

	flash-controller@4001E000 {
			compatible = "nrf,nrf51-flash-controller";
			reg = <0x4001E000 0x518>;

			#address-cells = <1>;
			#size-cells = <1>;

			flash0: flash@0 {
				compatible = "soc-nv-flash";
				reg = <0x00000000 DT_FLASH_SIZE>;
				write-block-size = <4>;
			};
	};

	sram0: memory@20000000 {
		device_type = "memory";
		compatible = "mmio-sram";
		reg = <0x20000000 DT_SRAM_SIZE>;
	};

	soc {
		uart0: uart@40002000 {
			compatible = "nordic,nrf-uart";
			reg = <0x40002000 0x1000>;
			interrupts = <2 1>;
			status = "disabled";
			label = "UART_0";
		};
	};
};

&nvic {
	arm,num-irq-priority-bits = <2>;
};