[PATCH v5 2/4] drm: Add vrr_enabled property to drm CRTC

[Michel Dänzer]

On 2018-10-13 7:38 p.m., Christian König wrote:
> Am 12.10.2018 um 18:44 schrieb Nicholas Kazlauskas:
>> This patch introduces the 'vrr_enabled' CRTC property to allow
>> dynamic control over variable refresh rate support for a CRTC.
>>
>> This property should be treated like a content hint to the driver -
>> if the hardware or driver is not capable of driving variable refresh
>> timings then this is not considered an error.
>>
>> Capability for variable refresh rate support should be determined
>> by querying the vrr_capable drm connector property.
>>
>> It is worth noting that while the property is intended for atomic use
>> it isn't filtered from legacy userspace queries. This allows for Xorg
>> userspace drivers to implement support.
> 
> I'm honestly still not convinced that a per CRTC property is actually
> the right approach.
> 
> What we should rather do instead is to implement a target timestamp for
> the page flip.

You'd have to be more specific about how the latter could completely
replace the former. I don't see how it could.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer