[Intel-gfx] i915 driver doesn't find all Modelines that nouveau driver finds

[Chris Wilson]

On Sun, Mar 01, 2015 at 02:12:16PM -0500, Brian J. Murrell wrote:
> I have a dual-head set up here which I've recently changed the
> motherboard out and with it, removed an nVidia GT210 and replaced it
> with the on-board graphics that came on this:
> 
> CPU: Intel(R) Celeron(R) CPU G1840 @ 2.80GHz (Family: 6, Model: 60, Stepping: 3)
> 
> The monitors have remained the same through the changeout.
> 
> What I am finding is that the nouveau driver on the nVidia GT210 found a
> 1600x1200 at 75Hz modeline for the ViewSonic PS790-2 monitor attached:
> 
> [   207.432] (II) NOUVEAU(1): Modeline "1600x1200"x75.0  202.50  1600 1664 1856 2160  1200 1201 1204 1250 +hsync +vsync (93.8 kHz UeP)
> 
> but the intel driver doe not.  Both drivers found all remaining
> Modelines.

Gut feeling is that this is related to HDMIv1.2 versus later. HDMIv1.4a
should be available on Haswell, but ark.intel.com gave no confirmation
for G1840.

For reference the loop in pipe is bug 85346:
https://bugs.freedesktop.org/show_bug.cgi?id=85346

Can you please attach dmesg with drm.debug=6 on the command line?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre