Commit 33c99570 authored by Ivan Lipski's avatar Ivan Lipski Committed by Alex Deucher
Browse files

drm/amd/display: Allow VRR params change if unsynced with the stream 



[Why]
When changing resolution (e.g., 4K → FHD) in mirror/clone mode with
certain monitors, the monitor blanks and loses connection due to an early
exit in vrr_settings_require_update(). The function only checks if VRR
state, fixed refresh target, or min/max refresh rate range has changed.

During mode changes, if the calculated min/max refresh values remain the
same even though the stream's v_total changed, the function returns early
without updating vrr_params.adjust.v_total_min/max, leaving the monitor's
VRR timing parameters unsynced with the new mode, causing it to blank out.

[How]
Explicitly adjust VRR parameters to the stream's nominal v_total when VRR
is supported, but inactive.

Fixes: 6d31602a ("drm/amd/display: more liberal vmin/vmax update for freesync")
Reviewed-by: default avatarAurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: default avatarIvan Lipski <ivan.lipski@amd.com>
Signed-off-by: default avatarFangzhi Zuo <jerry.zuo@amd.com>
Tested-by: default avatarDan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 607df824)
parent 6623c5f9

drivers/gpu/drm/amd/display/modules/freesync/freesync.c

+11 −0
Original line number Diff line number Diff line
@@ -1260,6 +1260,17 @@ void mod_freesync_handle_v_update(struct mod_freesync *mod_freesync, 
		update_v_total_for_static_ramp(

				core_freesync, stream, in_out_vrr);

	}



	/*

	 * If VRR is inactive, set vtotal min and max to nominal vtotal

	 */

	 if (in_out_vrr->state == VRR_STATE_INACTIVE) {

		in_out_vrr->adjust.v_total_min =

			mod_freesync_calc_v_total_from_refresh(stream,

				in_out_vrr->max_refresh_in_uhz);

		in_out_vrr->adjust.v_total_max = in_out_vrr->adjust.v_total_min;

		return;

	}

}



unsigned long long mod_freesync_calc_nominal_field_rate(