(In reply to comment #178)
> (In reply to comment #172)
> > > Is there any patch I can try against 3.12.6?
> > 
> > You can try disabling additional dpm features as per comment 94.
> 
> The patch seems to fix the issue.
> Booting with only the second half is not enough (the voltage_control & the
> gfx_clock_gating changes):
> I experienced black screen freeze on boot & disabled accel another time.

To be clear all of the changes are necessary?

pi->voltage_control = false;
pi->gfx_clock_gating = false;
pi->mclk_ss = false;
pi->dynamic_pcie_gen2 = false;

Are things any better with my 3.14 branch (which contains some dpm rework):
http://cgit.freedesktop.org/~agd5f/linux/log/?h=drm-next-3.14