On Fri, Nov 4, 2011 at 10:26 AM, Chen Jie <ch...@lemote.com> wrote: > Hi all, > > I tried to create/pin ring BO in VRAM instead of GTT to debug some > ring-related problems. After I did this, it rendered a black screen in > X (on a X86 RS780E board), but radeon.test passed. > 'ps aux' shows X uninterruptibly sleeps on radeon. > > Curious why this does not work?
The tricky part is dealing with the HDP cache. Access to vram via the PCI FB BAR goes through the HDP cache, you have to make sure it's flushed properly before the GPU starts using the data there. To flush it, either read back from vram, or write 1 to the HDP_MEM_COHERENCY_FLUSH_CNTL register. We generally don't recommend putting the ring in vram. Alex > > > > Regards, > -- Chen Jie > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel > _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel
