FreeBSD 11, X and UEFI

If X doesn't start with message similar to "Cannot run in framebuffer mode. Please specify busIDs" and you are booting your system using UEFI you should install package drm-kmod, and make sure to load appropriate module before starting X (for example i915kms.ko), but beware that after installing package modules with same names will be present in both /boot/kernel and /boot/modules, so it is necessary to give full path to module to load (for example kldload /boot/modules/i915kms.ko).