Every time I would run
update-initramfs, I would receive the following warning on my SuperMicro machine:
update-initramfs: Generating /boot/initrd.img-5.4.0-42-generic
W: Possible missing firmware /lib/firmware/ast_dp501_fw.bin for module ast
This issue is well-known and harmless. It's just a hardcoded value that's checked by ASPEED driver and, if file is not present, results in this warning.
If you are tired of it and you just want to make driver happy, create an empty file at that spot:
And now the warning is gone. :)