Re: [PATCH v2 02/20] drm: Don't update plane properties for atomic planes if it stays the same

Maarten Lankhorst
2015-07-07T15:08:34Z

Op 07-07-15 om 14:10 schreef Daniel Vetter:
> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote:
>> Op 07-07-15 om 11:18 schreef Daniel Vetter:
>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote:
>>>> This allows the first atomic call during hw init to be a real modeset,
>>>> which is useful for forcing a recalculation.
>>> fbcon is optional, you can't rely on anything being done in any specific
>>> way. What exactly do you need this for, what's the implications?
>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout.
>> I want the first function to be the modeset, so we have a sane base to commit changes on.
>> Ideally this whole function would have a atomic counterpart which does it in one go. :)
> Yeah. Otoh as soon as we have atomic modeset working we can replace all
> the legacy entry points with atomic helpers, and then even plane_disable
> will be a full atomic modeset.
>
> What did fall apart with just touching properties/planes now?
Also when i915 is fully atomic it calculates in intel_modeset_compute_config
if a modeset is needed after the first atomic call. Right now because
intel_modeset_compute_config is only called in set_config so this works as expected.
Otherwise drm_plane_force_disable or rotate_0 will force a modeset,
and if the final mode is different this will introduce a double modeset.