On Mon, Dec 28, 2020 at 1:51 PM Mario Kleiner <mario.kleiner.de@xxxxxxxxx> wrote: > > Hi and happy post-christmas! > > I wrote a patch 1/1 that now checks plane scaling factors against > the pixel-format specific limits in the asic specific dc_plane_cap > structures during atomic check and other appropriate places. > > This should prevent things like asking for scaling on fp16 framebuffers > if the hw can't do that. Hopefully this will now allow to safely enable > fp16 scanout also on older asic's like DCE-11.0, DCE-10 and DCE-8. > Patch 2/2 enables those DCE's now for fp16. > > I used some quickly hacked up of IGT test kms_plane_scaling, manually > hacking the src fb size to make sure the patch correctly accepts or > rejects atomic commits based on allowable scaling factors for rgbx/a > 8 bit, 10, and fp16. > > This fp16 support has been successfully tested with a Sea Islands / > DCE-8 laptop. I also confirmed that at least basic HDR signalling > over HDMI works for that DCE-8 machine with a HDR monitor. For this > i used the amdvlk driver which exposes fp16 since a while on supported > hw. Patches look good to me, but I'd like to get some feedback from the display folks as well. > > There are other bugs in DC wrt. DCE-8 though, which didn't prevent > my testing, but may be worth looking into. My DCE-8 machine scrambles > the video output picture somewhat under Vulkan (radv and admvlk) if the > output signal precision isn't 8 bpc, ie. on 6 bpc (eDP laptop panel) > and 10 bpc, 12 bpc (HDMI deep color on external HDR monitor). > > Another fun thing is getting a black screen if DC is enabled on at least > Linux 5.10+ (but not if i use the classic kms code in amdgpu-kms). If > i recompile the driver with a Ubuntu kconfig for Linux 5.9, the 5.10 > kernel works, and the only obvious DC related difference is that DC's > new SI / DCE-6 asic support is disabled at compile time. Fixed here: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6bdeff12a96c9a5da95c8d11fefd145eb165e32a Patch should be in stable for 5.10 as well. Alex _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
