On Mon, Apr 03, 2017 at 09:19:35AM +0200, Daniel Vetter wrote: > On Mon, Apr 3, 2017 at 8:25 AM, Manasi Navare <manasi.d.navare@xxxxxxxxx> wrote: > >> So in that case you do need userspace to re-request the same mode at the > >> same bpp? > > > > So yes because when userspace requests the same mode at same bpp, > > kernel will still call intel_dp->mod_valid which validates the mode > > against 18bpp so if the requested mode can be displayed at the lowest of > > 18bpp, then the kernel will try to do the modeset for that mode at lower > > bpp. What I am trying to say is irrespective of what bpp userspace requests, > > kernel will check if it can display that at the lowest of 18bpp. > > You're talking about two different bpp here I think. Eric talks about > the pixel format of the framebuffer, Manasi here about the bpp we send > over the wire. The kernel will auto-dither if the wire bpp is lower > than the stuff we scan out. Same with 6bpc panels really. > > Right now userspace can't request a specific bpp for the sink/pipe, > that's fully under the kernel's control. It only gets to set the pixel > format of fbs. > -Daniel > -- Yes so in that case, Eric we do need userspace to re-request the same mode at the same bpp or the same pixel format. And if this also fails, then we need Gnome or KDE to be re triggering a complete re probe. Regards Manasi > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
