With the linked patch you can build an OpenBSD kernel that will be able to start X and use the console (without X).
This is a big patch which needs a kernel rebuild, check how to do it here:
For a quick-ish spin I’d recommend using one of the git mirrors to clone the source, e.g.:
git clone --depth=1 ssh://anonymous@openbsd.gothub.org/src.git
git clone --depth=1 https://github.com/openbsd/src
You can apply the patch with git in the cloned src directory with:
git apply <patch>
Follow the build instructions from the linked FAQ and you should be able to boot into X.
X is slow, there is no Mali GPU driver available on OpenBSD, yet.
Disclaimer:
This is barely tested and not in the OpenBSD-current tree.
I’m not an OpenBSD developer and I’m not in any way, shape or form associated with the project itself.
The current state of this code is usable but most likely needs a lot of refinement. My editor thankfully did some reformatting that I didn’t intend to do, that is nothing to worry about.
In case you have not yet installed OpenBSD on your reform you can follow the install instructions here:
https://cdn.openbsd.org/pub/OpenBSD/snapshots/arm64/INSTALL.arm64
You need at least a serial connection to the machine. I recommend getting network running, too. Use the serial console to configure your Reforms wifi/ethernet and continue with ssh from there.
For good measure a picture of my MNT Reform:
Edit: Changed the pastebin link to show the raw code
Edit2: Explain some ugly parts in the patch
