On 2019-10-23 10:19 a.m., Lukáš Krejčí wrote: > On Mon, 2019-10-21 at 15:44 -0400, sunpeng.li@xxxxxxx wrote: >> From: Leo Li <sunpeng.li@xxxxxxx> >> >> [Why] >> >> Some LED panel drivers might not like fractional PWM. In such cases, >> backlight flickering may be observed. >> >> [How] >> >> Add a DC feature mask to disable fractional PWM, and associate it with >> the preexisting dc_config flag. >> >> The flag is only plumbed through the dmcu firmware, so plumb it through >> the driver path as well. >> >> To disable, add the following to the linux cmdline: >> amdgpu.dcfeaturemask=0x4 >> >> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204957 >> Signed-off-by: Leo Li <sunpeng.li@xxxxxxx> >> --- >> >> v2: Add bugzilla link >> >> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 +++ >> drivers/gpu/drm/amd/display/dc/dce/dce_abm.c | 4 ++++ >> drivers/gpu/drm/amd/include/amd_shared.h | 1 + >> 3 files changed, 8 insertions(+) > > Tested on Ubuntu 19.04, vanilla v5.3.7 kernel with the patch applied > and amdgpu.dcfeaturemask=0x4 added to the kernel command line, no > issues after 8 reboots. (The issue could be reproduced without > amdgpu.dcfeaturemask=0x4 on first boot.) > > Tested-by: Lukáš Krejčí <lskrejci@xxxxxxxxx> Applied, thanks! Leo _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel