Let me know. I had hopes the commiter would provide upstreaming effort proof but nothing there yet.

For a start it looks like you are wiring to spi0 and so fragment0 does not make sense. It also might be causing the pa14 pin problem as the op1 does not have an spi1. Pin pa14 is used on a uart output. I suggest you get rid of fragment0 and just use armbian-config to enable spi0.

Good find! Will look through that PR more closely this weekend. Thanks.

just wanted to ask, is there any way to recompile the included drivers in the kernel after a kernel update? for instance i built the intel xe and radeon drivers into my kernel when building this image, but the kernel updates from mainline apt seem to overwrite it and the drivers go away. even when dkms installed.

That's very useful. I'm nowhere near as practiced with this, so it'll take some time to digest and plan a way forward. It does fit with what seemed to be the case, though: it's device-level issues. I'll start poking around in the specific device differences and see what shows. The great hint you've found is that this is likely affecting all CSI cameras, not just the IMX708. That's most useful. I'm not at all worried about networkmanager, because the only tweak I made in the custom build was to use systemd-networkd, which (for me, anyway) is more straightforward for embedded/minimal/CLI usage. What I haven't yet done, and probably should, is switch to debugging this in something more vanilla, like a Pi 4. At least then I can compile libcamera and friends directly on the device. The Zero 2W should be the same -- he says, hopefully.