how to force fsck

[replabrobin]

After a recent crash I found I tried touch /forcefsck on my sheevaplug, but the boot didn't do an fsck. Seems systemd changed the way this works and I now need to edit the kernel command line and add fsck.mode=force. That's not easy with the uboot setup I have. Do I need to add some extra variable(s) so this sort of temporary change is easier to do?