drm/amd/display: handle range offsets in VRR ranges

commit 937844d upstream.

Need to check the offset bits for values greater than 255.

v2: also update amdgpu_dm_connector values.

Suggested-by: Mano Ségransan <mano.segransan@protonmail.com>
Tested-by: Mano Ségransan <mano.segransan@protonmail.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3203
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -10876,14 +10876,23 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
 				if (range->flags != 1)
 					continue;
 
-				amdgpu_dm_connector->min_vfreq = range->min_vfreq;
-				amdgpu_dm_connector->max_vfreq = range->max_vfreq;
-				amdgpu_dm_connector->pixel_clock_mhz =
-					range->pixel_clock_mhz * 10;
-
 				connector->display_info.monitor_range.min_vfreq = range->min_vfreq;
 				connector->display_info.monitor_range.max_vfreq = range->max_vfreq;
 
+				if (edid->revision >= 4) {
+					if (data->pad2 & DRM_EDID_RANGE_OFFSET_MIN_VFREQ)
+						connector->display_info.monitor_range.min_vfreq += 255;
+					if (data->pad2 & DRM_EDID_RANGE_OFFSET_MAX_VFREQ)
+						connector->display_info.monitor_range.max_vfreq += 255;
+				}
+
+				amdgpu_dm_connector->min_vfreq =
+					connector->display_info.monitor_range.min_vfreq;
+				amdgpu_dm_connector->max_vfreq =
+					connector->display_info.monitor_range.max_vfreq;
+				amdgpu_dm_connector->pixel_clock_mhz =
+					range->pixel_clock_mhz * 10;
+
 				break;
 			}