On Fri, Aug 05, 2016 at 11:04:21AM +0200, Enrico Weigelt, metux IT consult wrote: > On 05.08.2016 10:15, Daniel Vetter wrote: > > Hi, > > > There's a driver cap DRM_CAP_DUMB_PREFER_SHADOW for this. If set, > > render into a shadow buffer and copy over in bursts, otherwise you > > can assume that the memory is fully cpu cached and fast with random > > access. > > aaaah! > > nekrad@orion:~/src/linux$ git grep prefer_shadow drivers/gpu/drm/i915 > drivers/gpu/drm/i915/intel_display.c: dev->mode_config.prefer_shadow = 1; > > IOW: i915 driver (my notebook here has an i915) sets that flag, so > it seems my guess is right. > > Do we already have some suitable double-buffer helpers, which can detect > changed regions and copy over in bursts, so userland doesn't > need extra logic for that ? (hmm, maybe some cow + pagefault magic?) > > ... seems I need to give it some further thoughts ... DIRTY_FB ioctl. But that's for other manual uplaod displays and similar things. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
