Hello everyone, I want to useĀ uart4 port for zigbee2mqtt,but I don't know how to activates it.
The overlay works normally in a running system.
See this topic. The kernel already has everything, you only need to add the necessary overlay immediately in a working system.
No complicated steps with old u-boot scripts are needed. You can change everything on the fly in a running system.
https://www.96boards.org/documentation/consumer/dragonboard/dragonboard410c/guides/dt-overlays.md.html#32-loading-overlays-via-configfs