[PATCH 1/2] drm: Add new DRM_IOCTL_MODE_GETPLANE2

[Lucas Stach]

Hi Ben,

Am Dienstag, den 04.04.2017, 12:41 -0700 schrieb Ben Widawsky:
> On 17-04-04 11:07:26, Daniel Stone wrote:
> >Hi,
> >
> >On 1 April 2017 at 19:47, Rob Clark <robdclark at gmail.com> wrote:
> >> On Tue, Dec 20, 2016 at 7:12 PM, Kristian H. Kristensen
> >> <hoegsberg at gmail.com> wrote:
> >>> This new ioctl exctends DRM_IOCTL_MODE_GETPLANE, by returning
> >>> information about the modifiers that will work with each format.
> >>
> >> So, just to toss out a completely different idea..
> >>
> >> What if instead of a new ioctl, we had a read-only blob property
> >> (which encoded the info basically the same way, plus the fourcc's)?
> >>
> >> If we do writeback via some sort of OUT_FB_ID property on plane/crtc,
> >> we will need the same sort of format information so userspace knows
> >> what output formats (and modifiers) are supported.  So re-using the
> >> same blob property layout (and userspace parsing) seems useful.
> >
> >I'd definitely be cool with this. It doesn't make our lives any easier
> >or more difficult in terms of parsing, and it also avoids a dep on new
> >libdrm API/ABI, which is always nice. If anyone types this up, I'll
> >happily port the Weston WIP.
> >
> >Cheers,
> >Daniel
> 
> Okay. Sounds like we have consensus. I'm working on it now. I think like Rob
> said on IRC, a good amount of it will be reusable from GET_PLANE2. I'm a bit new
> to the binary blob props, so if anyone has a strong opinion on how it should
> look, please speak now. Otherwise, I'll just wire up something.
> 
Can you tell me the status of this?
I'm looking at adding tiled scanout to imx-drm and just want to know if
it's worth to hold my breath for the reworked patch to arrive.

Regards,
Lucas