How far have you gotten it to boot? There’s two working stacks I’ve used with the Odyssey:
- Mainline linux with some extra patches, mainline barebox, patched arm trusted firmware
- Seeed’s kernel, Seeed’s u-boot
If you’re using stock Buildroot you might have to choose some forks for the kernel/u-boot, and change the dts. Try using Seeed’s kernel and u-boot.