Greetings,
I have been working on getting Arch ARM aarch64 to run on a Raspberry Pi Compute Module 4, and so far it won't run but I have made some progress.
I have a CM4, with 16GB of EMMC and 4GB of RAM, mounted in a Compute Module 4 IO Board.
Following these directions: https://archlinuxarm.org/platforms/armv8/broadcom/raspberry-pi-4 I attempted to install the code contained in ArchLinuxARM-rpi-aarch64-latest.tar.gz to the EMMC, however it wouldn't boot. The first problem I discovered was the the device tree blob for the CM4 was missing. Luckily I had one from a working installation of Manjaro, and I copied it (bcm2711-rpi-cm4.dtb) to the /boot/dtbs/broadcom directory.
Now the kernel would load, but a new problem appeared, which is illustrated by the attached photo. See towards the bottom where it complains about not being able to find modules.devname.
Basically, the system can't find the EMMC even though it just loaded the kernel from it! The partition UUID that it's looking for is the correct one, and it shows up when the EMMC is connected to another computer via USB using rpiboot.
Lots of searching on the internet turned up a common solution: rebuild the initramfs files using mkinitcpio. Having successfully installed the same software on a RPi 4, I used it as a "build" machine, and mounted the two partitions from the CM4 and then ran arch-chroot. Unfortunately this had no effect at all on the problem, with the CM4 still failing to boot in exactly the same way.
Next, back into the chroot environment, I updated everything using 'pacman -Syu', and as part of this update process, it ran mkinitcpio again.
Still no joy. I get exactly the same result.
Also, this process is complicated by the fact that I haven't yet figured out how to power-up the CM4's USB ports so an attached keyboard will work, which would at least allow me to use the "emergency shell" that it drops into. In the official RPi and Manjaro installations, adding "dtoverlay=dwc2,dr_mode=host" to the config.txt file accomplishes this, but this aarch64 version doesn't seem to use overlays.
All assistance gratefully accepted. Thanks.