From 871512e36f9c1c2cb4e62eb860ca0438800e4d63 Mon Sep 17 00:00:00 2001 From: Sung-huai Wang Date: Thu, 13 Jun 2024 15:22:17 +0800 Subject: [PATCH] drm/amd/display: Add workaround to restrict max frac urgent for DPM0 [WHY] Underflow occurs on some platforms when urgent BW is close to the maximum in DPM0. [HOW] It does not occur at DPM1, so as a workaround restrict the maximum amount and increase the lowest state index for clock states until we're out of DPM0. Adds DML2 config options to specify this pe platform as required. Reviewed-by: Nicholas Kazlauskas Signed-off-by: Alex Hung Signed-off-by: Sung-huai Wang Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- .../gpu/drm/amd/display/dc/dml2/dml2_wrapper.c | 15 +++++++++++++++ .../gpu/drm/amd/display/dc/dml2/dml2_wrapper.h | 2 ++ .../display/dc/resource/dcn35/dcn35_resource.c | 3 ++- 3 files changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.c index f6310408dbba..f4038ac2e476 100644 --- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.c +++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.c @@ -628,6 +628,21 @@ static bool dml2_validate_and_build_resource(const struct dc *in_dc, struct dc_s if (result) { unsigned int lowest_state_idx = s->mode_support_params.out_lowest_state_idx; + double min_fclk_mhz_for_urgent_workaround = (double)dml2->config.min_fclk_for_urgent_workaround_khz / 1000.0; + double max_frac_urgent = (double)dml2->config.max_frac_urgent_for_min_fclk_x1000 / 1000.0; + + if (min_fclk_mhz_for_urgent_workaround > 0.0 && max_frac_urgent > 0.0 && + (dml2->v20.dml_core_ctx.mp.FractionOfUrgentBandwidth > max_frac_urgent || + dml2->v20.dml_core_ctx.mp.FractionOfUrgentBandwidthImmediateFlip > max_frac_urgent)) { + unsigned int forced_lowest_state_idx = lowest_state_idx; + + while (forced_lowest_state_idx < dml2->v20.dml_core_ctx.states.num_states && + dml2->v20.dml_core_ctx.states.state_array[forced_lowest_state_idx].fabricclk_mhz <= min_fclk_mhz_for_urgent_workaround) { + forced_lowest_state_idx += 1; + } + lowest_state_idx = forced_lowest_state_idx; + } + out_clks.dispclk_khz = (unsigned int)dml2->v20.dml_core_ctx.mp.Dispclk_calculated * 1000; out_clks.p_state_supported = s->mode_support_info.DRAMClockChangeSupport[0] != dml_dram_clock_change_unsupported; if (in_dc->config.use_default_clock_table && diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.h b/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.h index 20b3970c0857..79bf2d757804 100644 --- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.h +++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_wrapper.h @@ -237,6 +237,8 @@ struct dml2_configuration_options { bool use_clock_dc_limits; bool gpuvm_enable; struct dml2_soc_bb *bb_from_dmub; + int max_frac_urgent_for_min_fclk_x1000; + int min_fclk_for_urgent_workaround_khz; }; /* diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c index 67ab8c1962ff..1ce0f9ecff9c 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c @@ -2152,8 +2152,9 @@ static bool dcn35_resource_construct( dc->dml2_options.callbacks.can_support_mclk_switch_using_fw_based_vblank_stretch = &dcn30_can_support_mclk_switch_using_fw_based_vblank_stretch; dc->dml2_options.max_segments_per_hubp = 24; - dc->dml2_options.det_segment_size = DCN3_2_DET_SEG_SIZE;/*todo*/ + dc->dml2_options.max_frac_urgent_for_min_fclk_x1000 = 900; + dc->dml2_options.min_fclk_for_urgent_workaround_khz = 400 * 1000; if (dc->config.sdpif_request_limit_words_per_umc == 0) dc->config.sdpif_request_limit_words_per_umc = 16;/*todo*/ -- 2.50.1