购买的开发板未使用UART,只能自己硬着头皮添加。但AT91的linux也是过于庞大,所以开始寻找切入点
首先看这篇文章:http://blog.youkuaiyun.com/21cnbao/article/details/8457546
有了这个设备树,问题就简化了,所以在/linux-at91/arch/arm/boot/dts/中看到有:
先看sama5d3.dtsi,如usart0:
/ {
model = "Atmel SAMA5D3 family SoC";
compatible = "atmel,sama5d3";
interrupt-parent = <&aic>;
aliases {
serial0 = &dbgu;
serial1 = &usart0;
serial2 = &usart1;
serial3 = &usart2;
serial4 = &usart3;
gpio0 = &pioA;
gpio1 = &