Please anyone tell me how to configure UART3 on UEXT1.
in #olinuxino-overlay its not showing uart3.
i'm using python library so PB0 and PB1 pins are not working so i'm using UEXT1 uart.
Thanx in advance.
You need to load dtb/dts that enables it. Use the same dtb layout as for the UART2 one:
https://github.com/OLIMEX/olinuxino-overlays/blob/master/sun50i-a64/sun50i-a64-uart2.dts
You can also check the Armbian UART3 dtb/dts:
https://github.com/armbian/sunxi-DT-overlays/blob/master/sun50i-a64/sun50i-a64-uart3.dts
How to do it?
Is there any source?
Haven't work on kernel level so don't know how to do it.
Thanks.
Your issue is somewhere else. It seems UART3 is already enabled for a64 boards by default, you don't need to enable it via olinuxino-overlay:
https://github.com/OLIMEX/linux-olimex/blob/release-20210821-v5.10.60/arch/arm64/boot/dts/allwinner/sun50i-a64-olinuxino-1G.dts
&uart3 {
pinctrl-names = "default";
pinctrl-0 = <&uart3_ph_pins>;
status = "okay";
};