The Intel SOC AP42 system is not supported by Grub2-EFI, but boots using rEFInd (see article at http://rglinuxtech.com/?p=2021 ).
I had hoped to prevent the ‘automatic’ (re)install of grub2-efi etc by masking the (minimal) grub installation of grubby etc. – necessary to support the Kernel
# make install function – using
# rpm -e --justdb --nodeps <package>. I then found that – for some reason – the rEFInd install was still overwritten during
# dnf system-upgrade reboot etc..
Fortunately the re-install of rEFInd on this system was relatively simple. I created a bootable USB stick with the AltLinux Rescue Disk installed – which uses rEFInd (see https://en.altlinux.org/Rescue ), and booted from this. Then all I had to do was run
# refind-install --usedefault /dev/mmcblk0p1 to get the boot working again, with my existing rEFInd config. Note that this is different from the usual grub2 install, and the target is the EFI partition itself.
Robert Gadsdon July 15, 2018.