drm/amd/display: Fix bug that causes black screen

Ignore MSA bit on DP display is usually set during SetTimings, but
there was a case where the module thought refresh rate was not valid
and ignore MSA bit was not set.

Later, a valid refresh rate range was requested but since ignore MSA bit
not set, it caused black screen.

Issue if with how the module checked for VRR support. Fix up that logic.
DM should call new valid_range function to determine if timing is supported.

Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 6 insertions, 12 deletions

diff --git a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
index be6a6c63b4cc..4887c888bbe7 100644
--- a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
+++ b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
@@ -613,7 +613,6 @@ 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;
-        bool nominal_field_rate_in_range = true;
         unsigned int refresh_range = 0;
         unsigned int min_refresh_in_uhz = 0;
         unsigned int max_refresh_in_uhz = 0;
@@ -638,15 +637,6 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync,
         if (max_refresh_in_uhz > nominal_field_rate_in_uhz)
                 max_refresh_in_uhz = nominal_field_rate_in_uhz;
 
-        /* Allow for some rounding error of actual video timing by taking ceil.
-         * For example, 144 Hz mode timing may actually be 143.xxx Hz when
-         * calculated from pixel rate and vertical/horizontal totals, but
-         * this should be allowed instead of blocking FreeSync.
-         */
-        if ((min_refresh_in_uhz / 1000000) >
-                        ((nominal_field_rate_in_uhz + 1000000 - 1) / 1000000))
-                nominal_field_rate_in_range = false;
-
         // 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;
@@ -658,10 +648,14 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync,
 
         in_out_vrr->state = in_config->state;
 
-        if ((in_config->state == VRR_STATE_UNSUPPORTED) ||
-                                (!nominal_field_rate_in_range)) {
+        if (in_config->state == VRR_STATE_UNSUPPORTED) {
                 in_out_vrr->state = VRR_STATE_UNSUPPORTED;
                 in_out_vrr->supported = false;
+                in_out_vrr->adjust.v_total_min = stream->timing.v_total;
+                in_out_vrr->adjust.v_total_max = stream->timing.v_total;
+
+                return;
+
         } else {
                 in_out_vrr->min_refresh_in_uhz = min_refresh_in_uhz;
                 in_out_vrr->max_duration_in_us =