drm/amd/display: Added case for when RR equals panel's max RR using freesync

[WHY]
Rounding error sometimes occurs when the refresh rate is equal to a panel's
max refresh rate, causing HDMI compliance failures.

[HOW]
Added a case so that we round up to avoid v_total_min to be below a panel's
minimum bound.

Reviewed-by: Jun Lei <jun.lei@amd.com>
Signed-off-by: Harold Sun <Harold.Sun@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit fe7645d22bc0f7c1558296538ec49987bf268ef6)

diff --git a/drivers/gpu/drm/amd/display/dc/dc_hw_types.h b/drivers/gpu/drm/amd/display/dc/dc_hw_types.h
index d562ddeca51260db98fc92ec3a4823d8164a9e53..c9f6c6275ca1b561873d1421826179ff6f43561a 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dc_hw_types.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_hw_types.h
@@ -974,6 +974,7 @@ struct dc_crtc_timing {
        uint32_t pix_clk_100hz;
 
        uint32_t min_refresh_in_uhz;
+       uint32_t max_refresh_in_uhz;
 
        uint32_t vic;
        uint32_t hdmi_vic;

diff --git a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
index 3ba9b62ba70b8d512e9c555a751a593f6d217739..250f09922d2fa1245d0c7277b1dc7f86d560a477 100644 (file)
--- a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
+++ b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c
@@ -155,6 +155,14 @@ unsigned int mod_freesync_calc_v_total_from_refresh(
                v_total = div64_u64(div64_u64(((unsigned long long)(
                                frame_duration_in_ns) * (stream->timing.pix_clk_100hz / 10)),
                                stream->timing.h_total), 1000000);
+       } else if (refresh_in_uhz >= stream->timing.max_refresh_in_uhz) {
+               /* When the target refresh rate is the maximum panel refresh rate
+                * round up the vtotal value to prevent off-by-one error causing
+                * v_total_min to be below the panel's lower bound
+                */
+               v_total = div64_u64(div64_u64(((unsigned long long)(
+                               frame_duration_in_ns) * (stream->timing.pix_clk_100hz / 10)),
+                               stream->timing.h_total) + (1000000 - 1), 1000000);
        } else {
                v_total = div64_u64(div64_u64(((unsigned long long)(
                                frame_duration_in_ns) * (stream->timing.pix_clk_100hz / 10)),