The kernel boots on the device. The system can be accessed via SSH over USB. Display did not initialize but I did not try any further yet. Other than that I have not yet tested more of the peripherals. Even though there is already mainline support for the SOC (SDM670), I started of with the downstream kernel from LineageOS as reference. I do not have experience with mainline kernel development at all. This will give other contributors (my self included) a starting point for further development.