Hi,
This is my first try to add a board to armbian build system.
I got a BPI M2S since several months, but only had time recently to investigate on this promising SBC.
I made a PR here, if somebody wants to try it: https://github.com/armbian/build/pull/4597
The main improvements are to be done for the dts file, since I'm not an expert about such file definition. Only 1 ethernet of the Gbit ports is working, since I copy the config from vim3 that share the same hardware for it.
I didn't try to customize u-boot and I use the one for radxa zero2 that works to launch armbian on the board.
armbianmonitor -u is here: https://paste.armbian.com/piyuqajeye