[Intel-gfx] brix pro + dell UP3214Q, 3840x2160 @ 60 Hz

[Damien Lespiau]

On Tue, Mar 04, 2014 at 09:38:40PM +0100, Kenneth Johansson wrote:
> On 2014-03-04 17:12, Jani Nikula wrote:
> >On Tue, 04 Mar 2014, Kenneth Johansson <ken at kenjo.org> wrote:
> >>So I have a brix pro that is a i7 4700R with Intel Iris Pro Graphics 5200.
> >>and I 4k display from dell that can do 3840 x 2160  at 60 Hz (DP1.2)
> >>
> >>So both end should be ok. But when I try daily build of ubuntu as of
> >>yesterday all I get is 3840 x 2160 at 30Hz. I really hope this is just
> >>some software thing as 30Hz is not usable but the display is really
> >>crisp so I relly relly dont want to have to return it.
> >>
> >>I also noticed that when I go to console mode something gets configured
> >>wrong. I do get picture but the kernel manage to get the dimensions
> >>wrong so several 3-4 lines of the console is below the bottom and can't
> >>be seen.
> >Please try drm-intel-nightly branch of [1]. It has the code to enable
> >higher frequencies for DP 1.2:
> Tried that same result. I turned on drm.debug=0x4 but for me the
> only thing I can see is that the 60Hz mode is not in the list

The EDID doesn't even list the 4k at 60 fps mode, to me, this looks like it
may be of those monitors that need DP 1.2 MST to work (a feature we
don't have implemented in the kernel and that needs quite a bit of
work). It could be a totally wrong guess though, what monitor are we
talking about?

-- 
Damien