Hi Christian,
this doesn't look good:
DOMAIN: 0000 missing read_resources
None of your PCI resources are considered and also not the DRAM which is probably the cause of
Payload being loaded below 1MiB without region being marked as RAM usable.
Maybe no RAM is known at all at this point.
It's hard to tell where this comes from without seeing your code. If you could publish it somewhere, that would help us to help you. Shot in the dark: Do you have a resource `domain` in your `devicetree.cb`? Another cause could be that `src/northbridge/intel/i440bx/northbridge.c` is not linked into your build. That might be a matter of your `.config` file and the board's `Kconfig`.
Why 4.1 btw.? i440bx is still on our main branch.
Hope this helps, Nico