From 5a6b5458699d8e6fdb5ae09d950935a48b79f8c7 Mon Sep 17 00:00:00 2001 From: Aric Cyr Date: Wed, 11 Mar 2020 18:10:20 -0400 Subject: [PATCH] drm/amd/display: LFC not working on 2.0x range monitors (v2) [Why] Nominal pixel clock and EDID information differ in precision so although monitor reports maximum refresh is 2x minimum, LFC was not being enabled. [How] Use minimum refresh rate as nominal/2 when EDID dictates that min refresh = max refresh/2. v2: squash in 64 bit divide fix Signed-off-by: Aric Cyr Reviewed-by: Nicholas Kazlauskas Acked-by: Rodrigo Siqueira Signed-off-by: Alex Deucher --- .../drm/amd/display/modules/freesync/freesync.c | 34 ++++++++++++---------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c index 4e54282..c33454a 100644 --- a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c +++ b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c @@ -734,6 +734,7 @@ 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 long long rounded_nominal_in_uhz = 0; unsigned int refresh_range = 0; unsigned long long min_refresh_in_uhz = 0; unsigned long long max_refresh_in_uhz = 0; @@ -750,17 +751,20 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, min_refresh_in_uhz = in_config->min_refresh_in_uhz; max_refresh_in_uhz = in_config->max_refresh_in_uhz; - // Don't allow min > max - if (min_refresh_in_uhz > max_refresh_in_uhz) - min_refresh_in_uhz = max_refresh_in_uhz; - // Full range may be larger than current video timing, so cap at nominal if (max_refresh_in_uhz > nominal_field_rate_in_uhz) max_refresh_in_uhz = nominal_field_rate_in_uhz; // Full range may be larger than current video timing, so cap at nominal - if (min_refresh_in_uhz > nominal_field_rate_in_uhz) - min_refresh_in_uhz = nominal_field_rate_in_uhz; + if (min_refresh_in_uhz > max_refresh_in_uhz) + min_refresh_in_uhz = max_refresh_in_uhz; + + // If a monitor reports exactly max refresh of 2x of min, enforce it on nominal + rounded_nominal_in_uhz = + div_u64(nominal_field_rate_in_uhz + 50000, 100000) * 100000; + if (in_config->max_refresh_in_uhz == (2 * in_config->min_refresh_in_uhz) && + in_config->max_refresh_in_uhz == rounded_nominal_in_uhz) + min_refresh_in_uhz = div_u64(nominal_field_rate_in_uhz, 2); if (!vrr_settings_require_update(core_freesync, in_config, (unsigned int)min_refresh_in_uhz, (unsigned int)max_refresh_in_uhz, @@ -792,11 +796,6 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, refresh_range = in_out_vrr->max_refresh_in_uhz - in_out_vrr->min_refresh_in_uhz; - in_out_vrr->btr.margin_in_us = in_out_vrr->max_duration_in_us - - 2 * in_out_vrr->min_duration_in_us; - if (in_out_vrr->btr.margin_in_us > BTR_MAX_MARGIN) - in_out_vrr->btr.margin_in_us = BTR_MAX_MARGIN; - in_out_vrr->supported = true; } @@ -804,9 +803,14 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, 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) + if (in_out_vrr->max_refresh_in_uhz < (2 * in_out_vrr->min_refresh_in_uhz)) in_out_vrr->btr.btr_enabled = false; + else { + in_out_vrr->btr.margin_in_us = in_out_vrr->max_duration_in_us - + 2 * in_out_vrr->min_duration_in_us; + if (in_out_vrr->btr.margin_in_us > BTR_MAX_MARGIN) + in_out_vrr->btr.margin_in_us = BTR_MAX_MARGIN; + } in_out_vrr->btr.btr_active = false; in_out_vrr->btr.inserted_duration_in_us = 0; @@ -1008,8 +1012,8 @@ unsigned long long mod_freesync_calc_nominal_field_rate( unsigned int total = stream->timing.h_total * stream->timing.v_total; /* Calculate nominal field rate for stream, rounded up to nearest integer */ - nominal_field_rate_in_uhz = stream->timing.pix_clk_100hz / 10; - nominal_field_rate_in_uhz *= 1000ULL * 1000ULL * 1000ULL; + nominal_field_rate_in_uhz = stream->timing.pix_clk_100hz; + nominal_field_rate_in_uhz *= 100000000ULL; nominal_field_rate_in_uhz = div_u64(nominal_field_rate_in_uhz, total); -- 2.7.4