On Fri, Dec 09, 2016 at 10:44:16PM +1100, Benjamin Herrenschmidt wrote: > On Fri, 2016-12-09 at 09:34 +0100, Daniel Vetter wrote: > > Yeah if you have discrete vram then your dumb display driver isn't all > > that pretty. We essentially just have the few drivers Dave hacked up to be > > able to boot some servers. And there's definitely lots of room for more > > shared code for those, and also some better infrastructure and helpers to > > share more cod and make them better. > > > > The massive pile of dumb framebuffers we all merged over the past 2 years > > all use system/dma memory for scanout, and for those we have the very nice > > cma helpers that take care of everything for you. > > Do they work if the system/DMA memory has to be physically contiguous > and at a fixed address ? The AST "ARM side" GPU is like that. Yeah, if you wire up the dma_alloc_coherent to cma you'll get a contiguous buffer pinned into place. > > So it is possible, only reason vram dumb buffers look worse is that there's > > only 3 and no one cares about them, vs about 20 and a very active community > > of contributors (also for core drm improvements) for the other case. > > Well, we could move offb to drm while at it I suppose that would be another > one (offb is the "dumb driver based on pre-programmed output by firmware). One of the still in-flight drm drivers is the simpledrm thing meant for all kinds of firmware drivers like efifb and similar things on arm for pre-programmed output set up by firmware. I.e. no modeset support and otherwise a lot of fake to make it work as drm driver, but the idea that it's good enough until your real drm driver takes over. -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
