(In reply to Michael Chang from comment #11) > Sorry I think the correct command is : > > grub2-install --with-platform=arm-efi -no-nvram --removable > --modules=serial The correct command seems to be: grub2-install --target=arm-efi --no-nvram --removable --modules=serial But it does not help. Even copying /usr/share/grub2/arm-efi/grub.efi does not show the grub menu on serial. So, maybe some drivers are missing/broken?