On Fri, Jun 23, 2017 at 03:35:30PM +0530, Sharma, Shashank wrote: > Regards > > Shashank > > > On 6/23/2017 2:50 PM, Daniel Vetter wrote: > > On Thu, Jun 22, 2017 at 10:33 AM, Sharma, Shashank > > <shashank.sharma@xxxxxxxxx> wrote: > > > > - The property values should be limited to what the driver can support, I > > > > guess that would mean limiting the available ycbcr modes? Or does all > > > > our hw support all the modes, including 420 (on the sink side)? > > > This property is targeted at DRM layer, so naturally its for all the HWs > > > along with Intel HW, so it serves a big range. > > > All our HDMI 1.4 sources support RGB444, and after this series, can support > > > YCBCR444. > > > All HDMI 2.0 sources should support YCBCR420, but they can declare this > > > using a bool variable which I added in patch 3 (ycbcr420_allowed) > > > As we are targeting both HDMI 1.4 as well as HDMI 2.0 (Src and Sink), as a > > > whole we are covering all options. > > Yes, we need to define values for everything, since it's a generic > > property. But for a given driver imo we should only allow the values > > that are actually supported. An example would be the rotation > > property, which supporsts X/Y-mirror and rotation by 90° steps. But on > > a given i915 platform we only register support for the stuff the > > driver/hw can do, e.g. pre-gen9 do not register 90/270° rotation. I > > think we should do the same here. See > > drm_plane_create_rotation_property(), specifically the > > supported_rotations parameter. > Ah, I got your point now, and its valid. > If you see the I915 level handlers of YCBCR functions (added in patch 10) > they are taking care of blocking > anything which is not supported by driver for this platform, based on: > - The source capability > - The sink capability > - User preference of the property. Yeah, runtime checks are needed on top (sometimes at least). But if we can't support a given mode for a given sink then we should take that into account when registering the property. Otherwise userspace tries stuff that can never succeed, which isn't a big problem with the TEST_ONLY atomic mode, just a bit silly. -Daniel > So on a whole, set of Intel platforms cover all the values of property, but > at driver level we make sure to allow only what is suitable for this source > + sink combination. > - Shashank > > > > Cheers, Daniel > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
