Hi,
I noticed that there is a fallback to the u-boot device tree for linux (esp. EFI boot) if no other device tree was found, see [1]. It seems this is working fine for imx devices, for example, where you can just boot a stock installer iso via EFI. It will just work and it is quite a nice feature as a fallback.
Now for the layerscape architecture, the ls1028a in my case, things are more difficult because the bindings differ between u-boot and linux - one which comes to mind is DSA and ethernet.
Which begs the general question, is it encouraged to have both bindings diverge? To me it seems, that most bindings in u-boot are ad-hoc and there is no real review or alignment but just added as needed, which is ok if they are local to u-boot. But since they are nowadays passed to linux (by default!) I'm not so sure anymore.
OTOH The whole structure around a .dts{,i} and -u-boot.dtsi looks like they should (could?) be shared between linux and u-boot.
-michael
[1] https://elixir.bootlin.com/u-boot/v2021.10-rc2/source/common/board_r.c#L471