>It looks like to reduce the size needed, the NVMe core uses the host DDR in order to work. Therefor, apple is not strictly following the specification regarding the initialisation.
Yikes.
Yikes.
I've started to give up on ARM embedded boards for the same reason. You need to build out images for all the different potential ARM systems if they don't use device trees. There are Intel Atom/AMD Geode Pi/Beagelboard clones that will boot up just like a desktop and you can install most Linux distributions right on them without modification.
If ARM ever decides to start selling an architecture spec instead of just a SoC spec, I think it would go a long way at making it a better platform. I'm pretty sure Apple would still ignore it f
Eventually (particularly with ACPI) it will become apparent to the ARM ecosystem, that they can make their devices compatible with the standards, or they can spend millions on engineering effort to build their own firmware/OS stacks that will perpetually be behind the capabilities of the rest of the ecosystem.