UEFI equivalent of boot.config? (Was: Re: [RFC] Deprecation and removal of the drm2 driver)

Hijacking a thread here,

> Turns out, you can't install FreeBSD using a USB stick image because the
> BIOS only support MBR. No idea why MBR support was dropped for the USB images.
> 
> In the end I had to find a CD burner, and after a couple of tries managed to
> install from CD.

On a somewhat related note - I recently installed 11.1-STABLE on a box
with support for both UEFI and "good old fashioned BIOS". I initially
used UEFI and GPT, but ended up switching to BIOS and MBR because I
needed boot.config to enable booting from an alternate partition.

Despite lots of Googling I couldn't find a simple way to do this using
config stored on the disk itself (e.g. having "0:ad(0,f)/boot/loader"
in /boot.config) with UEFI.

Does anybody know if this can be done using UEFI?

Steinar Haug, Nethelp consulting, sthaug_at_nethelp.no