[Natty-SRU] Lenovo x420s panel display corruption when mode-setting

[Herton Ronaldo Krzesinski]

On Mon, Oct 03, 2011 at 02:23:24PM +0100, Andy Whitcroft wrote:
> On Mon, Oct 03, 2011 at 01:19:55PM +0100, Andy Whitcroft wrote:
> 
> > Well its a vast and epic patch.  I am left wondering whether this is
> > a backport or a cherry-pick in this context, below its reported as a
> > backport which implies it was modified, but you say here "as-is" implying
> > the opposite.
> [...]
> > > Subject: [PATCH] drm/i915: add pipe/plane enable/disable functions
> > > 
> > > Add plane enable/disable functions to prevent duplicated code and allow
> > > us to easily check for plane enable/disable requirements (such as pipe
> > > enable, plane status, pll status etc).
> > 
> > It is clear that this description is inadequate if we are actually
> > changing pipe init order.  (Not that that is anything you should change
> > as it _is_ the upstream commit description.)  Bad Jesse.
> > 
> > > 
> > > Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> > > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > > 
> > > (Backport to 2.6.38.y)
> > 
> > BugLink: http://bugs.launchpad.net/bugs/812638
> > (backported from commit b24e71798871089da1a4ab049db2800afc1aac0c)
> > 
> > "backported from" if its modified, "cherry-picked from" if its not ... ?
> 
> Ok, having talked to Jose a bit on IRC I am now able to answer my own
> question.  Actually this patch is the merge of _two_ upstream commits
> only retaining one of the descriptions.
> 
> It is a merge of the two commits below:
> 
>   commit 65993d64a31844ad444694efb2d159eb9c883e49
>   Author: Jesse Barnes <jbarnes at virtuousgeek.org>
>   Date:   Tue Jan 4 15:09:29 2011 -0800
> 
>     drm/i915: don't enable plane, pipe and PLL prematurely
>     
>     On Ironlake+ we need to enable these in a specific order.
>     
>     Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
>     Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> and:
> 
>   commit b24e71798871089da1a4ab049db2800afc1aac0c
>   Author: Jesse Barnes <jbarnes at virtuousgeek.org>
>   Date:   Tue Jan 4 15:09:30 2011 -0800
> 
>     drm/i915: add pipe/plane enable/disable functions
>     
>     Add plane enable/disable functions to prevent duplicated code and allow
>     us to easily check for plane enable/disable requirements (such as pipe
>     enable, plane status, pll status etc).
>     
>     Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
>     Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> If we try applying these onto the current natty head the first is a clean
> cherry-pick, the second collised in context _only_ with the patch below,
> keeping both sides gives us the combined commit on this thread:
> 
>   commit bbeaf8811ba070fd186dfcabc957044c3a1149ac
>   Author: Keng-Yu Lin <keng-yu.lin at canonical.com>
>   Date:   Wed Jun 22 09:49:34 2011 +0800
> 
>     drm/i915: disable PCH ports if needed when disabling a CRTC
> 
> For me this should have been submitted as two patched as clearly the
> change in the first one is a key component.  From these discusssions it
> seems that this improves things from 100% failure to ~10% failure on
> boot.  It looks a lot like the changes in the second patch, such as
> waiting for vblank on enabling the pipes fixes that final 10%.

Just droping a note about the "drm/i915: disable PCH ports if needed
when disabling a CRTC", it's now reverted on current natty master,
because of regressions. So once pushed to master-next, I guess the
second patch will not collide anymore. I was just waiting for the natty
update to be copied to -proposed so I could push master to master-next
and do a proper startnewrelease, but may be I'll do something to get
the abis from the c-k-t ppa instead and sync master-next earlier.

> 
> -apw
> 

-- 
[]'s
Herton