From: Bayan Zabihiyan <bayan.zabihiyan@xxxxxxx> [ Upstream commit a463b263032f7c98c5912207db43be1aa34a6438 ] [Why] The math on deciding on how many "frames to insert" sometimes sent us over the max refresh rate. Also integer overflow can occur if we have high refresh rates. [How] Instead of clipping the frame duration such that it doesn’t go below the min, just remove a frame from the number of frames to insert. + Use unsigned long long for intermediate calculations to prevent integer overflow. Signed-off-by: Bayan Zabihiyan <bayan.zabihiyan@xxxxxxx> Reviewed-by: Aric Cyr <Aric.Cyr@xxxxxxx> Acked-by: Leo Li <sunpeng.li@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../amd/display/modules/freesync/freesync.c | 27 ++++++++++++------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c index 7c20171a3b6da..a53666ff6cf89 100644 --- a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c +++ b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c @@ -435,6 +435,12 @@ static void apply_below_the_range(struct core_freesync *core_freesync, /* Either we've calculated the number of frames to insert, * or we need to insert min duration frames */ + if (last_render_time_in_us / frames_to_insert < + in_out_vrr->min_duration_in_us){ + frames_to_insert -= (frames_to_insert > 1) ? + 1 : 0; + } + if (frames_to_insert > 0) inserted_frame_duration_in_us = last_render_time_in_us / frames_to_insert; @@ -887,8 +893,8 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, struct core_freesync *core_freesync = NULL; unsigned long long nominal_field_rate_in_uhz = 0; unsigned int refresh_range = 0; - unsigned int min_refresh_in_uhz = 0; - unsigned int max_refresh_in_uhz = 0; + unsigned long long min_refresh_in_uhz = 0; + unsigned long long max_refresh_in_uhz = 0; if (mod_freesync == NULL) return; @@ -915,7 +921,7 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, min_refresh_in_uhz = nominal_field_rate_in_uhz; if (!vrr_settings_require_update(core_freesync, - in_config, min_refresh_in_uhz, max_refresh_in_uhz, + in_config, (unsigned int)min_refresh_in_uhz, (unsigned int)max_refresh_in_uhz, in_out_vrr)) return; @@ -931,15 +937,15 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, return; } else { - in_out_vrr->min_refresh_in_uhz = min_refresh_in_uhz; + in_out_vrr->min_refresh_in_uhz = (unsigned int)min_refresh_in_uhz; in_out_vrr->max_duration_in_us = calc_duration_in_us_from_refresh_in_uhz( - min_refresh_in_uhz); + (unsigned int)min_refresh_in_uhz); - in_out_vrr->max_refresh_in_uhz = max_refresh_in_uhz; + in_out_vrr->max_refresh_in_uhz = (unsigned int)max_refresh_in_uhz; in_out_vrr->min_duration_in_us = calc_duration_in_us_from_refresh_in_uhz( - max_refresh_in_uhz); + (unsigned int)max_refresh_in_uhz); refresh_range = in_out_vrr->max_refresh_in_uhz - in_out_vrr->min_refresh_in_uhz; @@ -950,17 +956,18 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, in_out_vrr->fixed.ramping_active = in_config->ramping; in_out_vrr->btr.btr_enabled = in_config->btr; + if (in_out_vrr->max_refresh_in_uhz < 2 * in_out_vrr->min_refresh_in_uhz) in_out_vrr->btr.btr_enabled = false; + in_out_vrr->btr.btr_active = false; in_out_vrr->btr.inserted_duration_in_us = 0; in_out_vrr->btr.frames_to_insert = 0; in_out_vrr->btr.frame_counter = 0; in_out_vrr->btr.mid_point_in_us = - in_out_vrr->min_duration_in_us + - (in_out_vrr->max_duration_in_us - - in_out_vrr->min_duration_in_us) / 2; + (in_out_vrr->min_duration_in_us + + in_out_vrr->max_duration_in_us) / 2; if (in_out_vrr->state == VRR_STATE_UNSUPPORTED) { in_out_vrr->adjust.v_total_min = stream->timing.v_total; -- 2.20.1