From: George Shen Date: Wed, 6 Oct 2021 19:47:37 +0000 (-0400) Subject: drm/amd/display: Implement fixed DP drive settings X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=54fe00be270dd6fdb9e23c31a4497edec5a3609b;p=linux.git drm/amd/display: Implement fixed DP drive settings [Why] Currently there are use cases that require DP link to maintain fixed VS and PE in HW regardless of what the sink requests. BIOS integrated info table will specify whether we need to use the fixed drive settings, and the drive settings to use. [How] Implement changes to parse the integrated info table and set the fixed drive settings accordingly. Reviewed-by: Wenjing Liu Tested-by: Daniel Wheeler Acked-by: Agustin Gutierrez Signed-off-by: George Shen Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c b/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c index c17732fba0394..a4bef4364afd8 100644 --- a/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c +++ b/drivers/gpu/drm/amd/display/dc/bios/bios_parser2.c @@ -2321,6 +2321,8 @@ static enum bp_result get_integrated_info_v2_2( info->ext_disp_conn_info.checksum = info_v2_2->extdispconninfo.checksum; + info->ext_disp_conn_info.fixdpvoltageswing = + info_v2_2->extdispconninfo.fixdpvoltageswing; info->edp1_info.edp_backlight_pwm_hz = le16_to_cpu(info_v2_2->edp1_info.edp_backlight_pwm_hz); diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 96d2001ede613..a1fa50ddf43e5 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -1660,6 +1660,14 @@ static bool dc_link_construct_legacy(struct dc_link *link, DC_LOG_DC("BIOS object table - ddi_channel_mapping: 0x%04X", link->ddi_channel_mapping.raw); DC_LOG_DC("BIOS object table - chip_caps: %d", link->chip_caps); } + + if (link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) { + link->bios_forced_drive_settings.VOLTAGE_SWING = + (info->ext_disp_conn_info.fixdpvoltageswing & 0x3); + link->bios_forced_drive_settings.PRE_EMPHASIS = + ((info->ext_disp_conn_info.fixdpvoltageswing >> 2) & 0x3); + } + break; } } diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index e514506b19975..3313f2af139ff 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -1661,7 +1661,13 @@ static void override_training_settings( if (overrides->ffe_preset != NULL) lt_settings->ffe_preset = overrides->ffe_preset; #endif - + /* Override HW lane settings with BIOS forced values if present */ + if (link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN && + link->lttpr_mode == LTTPR_MODE_TRANSPARENT) { + lt_settings->voltage_swing = &link->bios_forced_drive_settings.VOLTAGE_SWING; + lt_settings->pre_emphasis = &link->bios_forced_drive_settings.PRE_EMPHASIS; + lt_settings->always_match_dpcd_with_hw_lane_settings = false; + } for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) { lt_settings->lane_settings[lane].VOLTAGE_SWING = lt_settings->voltage_swing != NULL ? diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h index 8902d642e719a..517950674729a 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_link.h +++ b/drivers/gpu/drm/amd/display/dc/dc_link.h @@ -178,6 +178,9 @@ struct dc_link { struct psr_settings psr_settings; + /* Drive settings read from integrated info table */ + struct dc_lane_settings bios_forced_drive_settings; + /* MST record stream using this link */ struct link_flags { bool dp_keep_receiver_powered; diff --git a/drivers/gpu/drm/amd/display/include/grph_object_ctrl_defs.h b/drivers/gpu/drm/amd/display/include/grph_object_ctrl_defs.h index 792652236c61b..dd974c428d23d 100644 --- a/drivers/gpu/drm/amd/display/include/grph_object_ctrl_defs.h +++ b/drivers/gpu/drm/amd/display/include/grph_object_ctrl_defs.h @@ -328,6 +328,7 @@ struct integrated_info { uint8_t gu_id[NUMBER_OF_UCHAR_FOR_GUID]; uint8_t checksum; + uint8_t fixdpvoltageswing; } ext_disp_conn_info; /* exiting long long time */ struct available_s_clk_list { diff --git a/drivers/gpu/drm/amd/display/include/link_service_types.h b/drivers/gpu/drm/amd/display/include/link_service_types.h index 9ffea7b405454..9a16fc8552542 100644 --- a/drivers/gpu/drm/amd/display/include/link_service_types.h +++ b/drivers/gpu/drm/amd/display/include/link_service_types.h @@ -117,6 +117,12 @@ struct link_training_settings { bool enhanced_framing; bool allow_invalid_msa_timing_param; enum lttpr_mode lttpr_mode; + + /* disallow different lanes to have different lane settings */ + bool disallow_per_lane_settings; + /* dpcd lane settings will always use the same hw lane settings + * even if it doesn't match requested lane adjust */ + bool always_match_dpcd_with_hw_lane_settings; }; /*TODO: Move this enum test harness*/