Marc:
...
> initrd
...

Just so I understand, isn't initrd is the old way to do it and the
new way is initramfs, so when you guys are talking about initrd,
you actually mean initramfs ?

initrd is described in (relative the kernel source directory)
Documentation/admin-guide/initrd.rst

initramfs is described in
Documentation/filesystems/ramfs-rootfs-initramfs.txt

Regards,
/Karl Hammar