This is a note to let you know that I've just added the patch titled drm/amd/display: Fix DC mode screen flickering on DCN321 to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-fix-dc-mode-screen-flickering-on-dcn.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 22792893efc5e7c916bf56f1702e3d4eba40c141 Author: Leo Ma <hanghong.ma@xxxxxxx> Date: Thu Apr 11 17:17:04 2024 -0400 drm/amd/display: Fix DC mode screen flickering on DCN321 [ Upstream commit ce649bd2d834db83ecc2756a362c9a1ec61658a5 ] [Why && How] Screen flickering saw on 4K@60 eDP with high refresh rate external monitor when booting up in DC mode. DC Mode Capping is disabled which caused wrong UCLK being used. Reviewed-by: Alvin Lee <alvin.lee2@xxxxxxx> Acked-by: Wayne Lin <wayne.lin@xxxxxxx> Signed-off-by: Leo Ma <hanghong.ma@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c index e9345f6554dbc..2428a4763b85f 100644 --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn32/dcn32_clk_mgr.c @@ -547,8 +547,12 @@ static void dcn32_update_clocks(struct clk_mgr *clk_mgr_base, * since we calculate mode support based on softmax being the max UCLK * frequency. */ - dcn32_smu_set_hard_min_by_freq(clk_mgr, PPCLK_UCLK, - dc->clk_mgr->bw_params->dc_mode_softmax_memclk); + if (dc->debug.disable_dc_mode_overwrite) { + dcn30_smu_set_hard_max_by_freq(clk_mgr, PPCLK_UCLK, dc->clk_mgr->bw_params->max_memclk_mhz); + dcn32_smu_set_hard_min_by_freq(clk_mgr, PPCLK_UCLK, dc->clk_mgr->bw_params->max_memclk_mhz); + } else + dcn32_smu_set_hard_min_by_freq(clk_mgr, PPCLK_UCLK, + dc->clk_mgr->bw_params->dc_mode_softmax_memclk); } else { dcn32_smu_set_hard_min_by_freq(clk_mgr, PPCLK_UCLK, dc->clk_mgr->bw_params->max_memclk_mhz); } @@ -581,8 +585,13 @@ static void dcn32_update_clocks(struct clk_mgr *clk_mgr_base, /* set UCLK to requested value if P-State switching is supported, or to re-enable P-State switching */ if (clk_mgr_base->clks.p_state_change_support && (update_uclk || !clk_mgr_base->clks.prev_p_state_change_support) && - !dc->work_arounds.clock_update_disable_mask.uclk) + !dc->work_arounds.clock_update_disable_mask.uclk) { + if (dc->clk_mgr->dc_mode_softmax_enabled && dc->debug.disable_dc_mode_overwrite) + dcn30_smu_set_hard_max_by_freq(clk_mgr, PPCLK_UCLK, + max((int)dc->clk_mgr->bw_params->dc_mode_softmax_memclk, khz_to_mhz_ceil(clk_mgr_base->clks.dramclk_khz))); + dcn32_smu_set_hard_min_by_freq(clk_mgr, PPCLK_UCLK, khz_to_mhz_ceil(clk_mgr_base->clks.dramclk_khz)); + } if (clk_mgr_base->clks.num_ways != new_clocks->num_ways && clk_mgr_base->clks.num_ways > new_clocks->num_ways) {