Re: [PATCH 34/36] drm/tegra: Track active planes in CRTC state

[Thierry Reding]

On Tue, Jan 20, 2015 at 12:18:45PM +0100, Daniel Vetter wrote:
> On Tue, Jan 20, 2015 at 11:48:53AM +0100, Thierry Reding wrote:
> > From: Thierry Reding <treding@xxxxxxxxxx>
> > 
> > Wrap struct drm_crtc_state in a driver-specific structure and add the
> > planes field which keeps track of which planes are updated or disabled
> > during a modeset. This allows atomic updates of the the display engine
> > at ->atomic_flush() time.
> > 
> > Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
> 
> commit 6ddd388ab222b66b596342becc76d5031c0e2fc8
> Author: Rob Clark <robdclark@xxxxxxxxx>
> Date:   Fri Nov 21 15:28:31 2014 -0500
> 
>     drm/atomic: track bitmask of planes attached to crtc
> 
> added this to the core since it seems to be generally useful. Does tegra
> need more?

That commit adds code to track planes that are being activated, whereas
this commit sets bits for all planes that are being changed, including
those that are being disabled.

The difference is important because we have "GO" bits for each of the
planes, so if one is being disabled we have to set the "GO" bit to make
sure the changes are applied on the next VBLANK.

Perhaps the subject should be updated to something like:

	drm/tegra: Track changed planes in CRTC state

?

Thierry

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