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RK3399-UART功能特點(diǎn)
1、UART （Universal Asynchronous Receiver/Transmitter），以下是linux 4.4 uart驅(qū)動(dòng)支持的一些特性︰
最高支持4M波特率
只有UART0和UART3支持硬件自動(dòng)流控
支持中斷傳輸模式
2、 DTS節(jié)點(diǎn)配置
使能，無(wú)需其他配置： &uart0 { status = "okay"; }; 使能后/dev/ttyS0 設(shè)備就可以使用。
3、關(guān)閉Linux串口打印
3.1 關(guān)掉FIQ debugger，Disable以下節(jié)點(diǎn)
fiq_debugger: fiq-debugger {
compatible = "rockchip,fiq-debugger";
rockchip,serial-id = <2>; 設(shè)置串口id
rockchip,signal-irq = <182>;
rockchip,wake-irq = <0>;
rockchip,irq-mode-enable = <1>; /* If enable uart uses irq instead of fiq */
rockchip,baudrate = <1500000>; /* Only 115200 and 1500000 */
pinctrl-names = "default";
pinctrl-0 = <&uart2c_xfer>; 配置iomux
status = “disabled”;
}
3.2 去掉earlyprintk=uart8250-32bit,0xff690000
chosen {
bootargs = "earlyprintk=uart8250-32bit,0xff690000";
};
3.3 在燒寫(xiě)parameter.txt
commandline：androidboot.console=ttyFIQ0，去掉ttyFIQ0。
3.4 android/device/rockchip/common/recovery/etc/init.rc
service recovery /sbin/recovery
#console 這個(gè)注釋掉
seclabel u:r:recovery:s0
4 打印串口2改為其他串口
fiq_debugger: fiq-debugger {
compatible = "rockchip,fiq-debugger";
rockchip,serial-id = <2>; 設(shè)置串口id
rockchip,signal-irq = <182>;
rockchip,wake-irq = <0>;
rockchip,irq-mode-enable = <1>; /* If enable uart uses irq instead of fiq */
rockchip,baudrate = <1500000>; /* Only 115200 and 1500000 */
pinctrl-names = "default";
pinctrl-0 = <&uart2c_xfer>; 配置iomux
};
chosen {
bootargs = "earlyprintk=uart8250-32bit,0xff690000"; 新串口的地址
};
以上所需信息都可以，通過(guò)串口設(shè)備的DTS節(jié)點(diǎn)獲取，舉個(gè)例子：
uart1: serial@ff190000 {
compatible = "rockchip,rk3399-uart", "snps,dw-apb-uart";
reg = <0x0 0xff190000 0x0 0x100>;
clocks = <&cru SCLK_UART1>, <&cru PCLK_UART1>;
clock-names = "baudclk", "apb_pclk";
interrupts = <GIC_SPI 98 IRQ_TYPE_LEVEL_HIGH>;
dmas = <&dmac_peri 2>, <&dmac_peri 3>;
dma-names = "tx", "rx";
reg-shift = <2>; reg-io-width = <4>;
pinctrl-names = "default";
/*pinctrl-0 = <&uart1_xfer>;*/
status = "disabled";
}; |
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