On Tue, Jan 27, 2015 at 02:11:18PM +0530, Shobhit Kumar wrote: > On 01/23/2015 08:52 PM, Daniel Vetter wrote: > >On Fri, Jan 23, 2015 at 03:14:41PM +0530, Shobhit Kumar wrote: > >>On 01/22/2015 06:53 PM, Jani Nikula wrote: > >>>On Thu, 22 Jan 2015, Shobhit Kumar <shobhit.kumar@xxxxxxxxxxxxxxx> wrote: > >>>>There had been a instance where we had to drive different resolution > >>>>(lower) than the native one. Also in VBT there is a field to make this > >>>>generic at least from driver perspective to give the needed target > >>>>resolution. In case target resolution is same as native, nothing gets > >>>>changed, else mode_fixup function adjusts the mode accordingly keeping > >>>>timing as same and enabling scalar. Might not be useful in general, but > >>>>did find a use internally. > >>> > >>>Can we just have the driver return the desired mode from .get_modes in > >>>that case? > >> > >>Okay, I think I did not explain correctly. Get modes is modified to give the > >>needed target mode only so that userspace creates buffer of the needed > >>resolution, but in fixup which is called at modeset, we correct the > >>adjusted_mode back to have native resolutions so that modeset is correctly > >>done. if we do not do like this, during modeset resolutions will be wrong as > >>per the timings. > > > >I'm confused. Can you please give an example in real numbers about the > >different resolution and how it's all fixed up in hw? > > > >E.g. 800x600 framebuffer -> pfit -> 1024x756 panel, > > > >get_modes gives 800x600, adjusted mode corrects to 1024x756. And please > > We had a 19x12 DSI panel which we needed to drive at 12x8 due to lack of > 12x8 panels for testing purposes. So get_modes returned 12x8 so that user > space gave 12x8 FBs, and internally in mode_fixup we adjusted correctly for > the 19x12 panel timings and enabled pfit Hm, is that a real use-case shipping to customers or just a hack for development? In the later case I think we can just hardcode the edid for edp ... -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
