I've installed the Ubuntu 24.04 image to eMMC storage. I'm trying to set up a mdadm RAID array. (Or is there some other recommended way to set up a RAID array with the CM3588?) I would like the array to open on boot.

mdadm isn't installed in this image by default. Normally, in order to get it to open a new RAID array on boot, I would add the array to mdadm.conf and then run update-initramfs to copy the updated mdadm.conf into the initrd. However, update-initramfs seems to be a no-op with the custom kernel package that the CM3588 uses; running it doesn't do anything.

An alternative would be to pass the array's details as a kernel boot argument. That would be fine with me if it works, but I'm not sure how bootloading works on the CM3588? So I'm not sure where the kernel boot arguments live?

I see instructions on how to modify the image prior to flashing it to eMMC storage. But I don't really want to re-flash the whole eMMC -- I have a bunch of stuff installed and configured, and anyway I don't set up RAID arrays very often and I'd rather not have to re-flash and reconfigure the whole system a bunch of times while I fiddle around figuring out how to get all of this working. I figure the relevant data must live somewhere -- any pointers to where i might find it?