amd radeon r7 m260 integrated or dedicated

Moving straight to the point, what I would like to know is if there is any chance to let the card work with the open source radeon graphics stack, since I don't want to rely on proprietary drivers which at present are actually even missing at all (it has been 4 months since the Zbook 14 G2 release and there is not even a trace of dedicated drivers, neither from AMD or HP.You cannot even find the M4150 official specs on AMD's official site.). The Broadwell hardware seems to be in very good shape with the open source drivers (Unity is running very smooth, as well as most of the applications I usually run for my work), but the AMD graphics is actually kept disabled which is a shame given the 1 GB of GDDR5 dedicated memory of the M4150 device. I have installed on it Ubuntu 14.04.2 LTS (need Linux on it for work) and generally speaking it works great, except for the AMD graphics part. My problem is the following: I have an HP Zbook 14 G2 laptop, which is equipped with Intel+AMD hybrid graphics, more specifically a Broadwell HD 5500 + AMD FirePro M4150 combination. This is my first post here so please be gentle.

Amd radeon r7 m260 integrated or dedicated