Re: [PATCH 08/21 v2] drm/i915: Add helper function to update scaler_users in crtc_state

Matt Roper
2015-03-25T20:58:36Z

On Wed, Mar 25, 2015 at 12:20:08PM -0700, Konduru, Chandra wrote:
...
> >
> > We're already calculating this in the plane check function; we should probably
> > just store the result in a plane_state field at that point so we don't have to re-
> > calculate it here.
>
> I think you are referring to sprite plane check, but this is not there in primary plane
> check function.

Well, it is, but it's hidden inside the drm plane helper function and
isn't directly in our i915 driver code.

I feel like "do these src/dest rectangles imply scaling?" is a question
that is going to be relevant to all drivers, not just i915, so it might
even be worth adding the field to the DRM core's state structure and
have the helper function set it for any drivers using the helper.
Hardware drivers could override this value, or could set it themselves
if they don't use the helper. Just a thought...

Matt

--
Matt Roper
Graphics Software Engineer
IoTG Platform Enabling & Development
Intel Corporation
(916) 356-2795