https://bugzilla.kernel.org/show_bug.cgi?id=206393 --- Comment #5 from Bjoern Franke (bjo@xxxxxxxxxxxxx) --- Bisected to 1ea8751bd28d1ec2b36a56ec6bc1ac28903d09b4 is the first bad commit commit 1ea8751bd28d1ec2b36a56ec6bc1ac28903d09b4 Author: Noah Abradjian <noah.abradjian@xxxxxxx> Date: Fri Sep 27 16:30:57 2019 -0400 drm/amd/display: Make clk mgr the only dto update point [Why] * Clk Mgr DTO update point did not cover all needed updates, as it included a check for plane_state which does not exist yet when the updater is called on driver startup * This resulted in another update path in the pipe programming sequence, based on a dppclk update flag * However, this alternate path allowed for stray DTO updates, some of which would occur in the wrong order during dppclk lowering and cause underflow [How] * Remove plane_state check and use of plane_res.dpp->inst, getting rid of sequence dependencies (this results in extra dto programming for unused pipes but that doesn't cause issues and is a small cost) * Allow DTOs to be updated even if global clock is equal, to account for edge case exposed by diags tests * Remove update_dpp_dto call in pipe programming sequence (leave update to dppclk_control there, as that update is necessary and shouldn't occur in clk mgr) * Remove call to optimize_bandwidth when committing state, as it is not needed and resulted in sporadic underflows even with other fixes in place Signed-off-by: Noah Abradjian <noah.abradjian@xxxxxxx> Reviewed-by: Jun Lei <Jun.Lei@xxxxxxx> Acked-by: Leo Li <sunpeng.li@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> .../gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c | 14 +++++++++----- drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c | 3 ++- drivers/gpu/drm/amd/display/dc/core/dc.c | 4 ---- drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c | 8 +------- 4 files changed, 12 insertions(+), 17 deletions(-) In contrast to #205915 it's not "fixable" via setting dpm_force_performance_level to high or low. -- You are receiving this mail because: You are watching the assignee of the bug. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
