[U-Boot] eMMC boot partition possible with an eMMC 4.2 controller ?

[Joakim Tjernlund]

Trying to figure out if it will be possible to boot u-boot from an eMMC boot partition using an
eMMC 4.2 controller(eMMC boot part. was introduced in 4.3) ?

I know this might not be the best list to ask this but I have been unable to find this out using Google
and I hope there is someone here that knows the answer.

 Jocke