RK3568平台（UART篇）UART端口注册流程

一.串口 9 控制器的设备树节点

uart9: serial@fe6d0000 
{ 
    compatible = "rockchip,rk3568-uart", "snps,dw-apb-uart"; 
    reg = <0x0 0xfe6d0000 0x0 0x100>; 
    interrupts = ;
    clocks = <&cru SCLK_UART9>, <&cru PCLK_UART9>; 
    clock-names = "baudclk", "apb_pclk"; 
    reg-shift = <2>; 
    reg-io-width = <4>; 
    dmas = <&dmac0 18>, <&dmac0 19>; 
    pinctrl-names = "default"; 
    pinctrl-0 = <&uart9m0_xfer>; 
    status = "disabled"; 
};

二.驱动源码分析

compatible 属性值为“snps,dw-apb-uart”。在 Linux 源码中搜索这个 值即可找到对应的 UART 驱动文件，此文件为 drivers/