[v6 1/3] drm/i915/dp: Attach and set drm connector VRR property

[Bhanuprakash Modem]

From: Aditya Swarup <aditya.swarup at intel.com>

This function sets the VRR property for connector based
on the platform support, EDID monitor range and DP sink
DPCD capability of outputing video without msa
timing information.

v5:
* Fix the vrr prop not being set in kernel (Manasi)
* Unset the prop on connector disconnect (Manasi)
v4:
* Rebase (Mansi)
v3:
* intel_dp_is_vrr_capable can be used for debugfs, make it
non static (Manasi)
v2:
* Just set this in intel_dp_get_modes instead of new hook (Jani)

Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Signed-off-by: Aditya Swarup <aditya.swarup at intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 27 +++++++++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_dp.h |  2 ++
 2 files changed, 29 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 42589cae766d..d0dba81cfb07 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -6149,6 +6149,9 @@ intel_dp_detect(struct drm_connector *connector,
 	if (status == connector_status_disconnected) {
 		memset(&intel_dp->compliance, 0, sizeof(intel_dp->compliance));
 		memset(intel_dp->dsc_dpcd, 0, sizeof(intel_dp->dsc_dpcd));
+		/*Reset the immutable VRR Capable property */
+		drm_connector_set_vrr_capable_property(connector,
+						       false);
 
 		if (intel_dp->is_mst) {
 			drm_dbg_kms(&dev_priv->drm,
@@ -6256,6 +6259,23 @@ intel_dp_force(struct drm_connector *connector)
 	intel_display_power_put(dev_priv, aux_domain, wakeref);
 }
 
+bool intel_dp_is_vrr_capable(struct drm_connector *connector)
+{
+	struct intel_dp *intel_dp = intel_attached_dp(to_intel_connector(connector));
+	const struct drm_display_info *info = &connector->display_info;
+	struct drm_i915_private *dev_priv = to_i915(connector->dev);
+
+	/*
+	 * DP Sink is capable of Variable refresh video timings if
+	 * Ignore MSA bit is set in DPCD.
+	 * EDID monitor range also should be atleast 10 for reasonable
+	 * Adaptive sync/ VRR end user experience.
+	 */
+	return INTEL_GEN(dev_priv) >= 12 &&
+		drm_dp_sink_can_do_video_without_timing_msa(intel_dp->dpcd) &&
+		info->monitor_range.max_vfreq - info->monitor_range.min_vfreq > 10;
+}
+
 static int intel_dp_get_modes(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
@@ -6264,6 +6284,10 @@ static int intel_dp_get_modes(struct drm_connector *connector)
 	edid = intel_connector->detect_edid;
 	if (edid) {
 		int ret = intel_connector_update_modes(connector, edid);
+
+		if (intel_dp_is_vrr_capable(connector))
+			drm_connector_set_vrr_capable_property(connector,
+							       true);
 		if (ret)
 			return ret;
 	}
@@ -7325,6 +7349,9 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect
 		connector->state->scaling_mode = DRM_MODE_SCALE_ASPECT;
 
 	}
+
+	if (INTEL_GEN(dev_priv) >= 12)
+		drm_connector_attach_vrr_capable_property(connector);
 }
 
 static void intel_dp_init_panel_power_timestamps(struct intel_dp *intel_dp)
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 0a8950f744f6..db895a3cd93f 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -14,6 +14,7 @@ enum pipe;
 enum port;
 struct drm_connector_state;
 struct drm_encoder;
+struct drm_connector;
 struct drm_i915_private;
 struct drm_modeset_acquire_ctx;
 struct drm_dp_vsc_sdp;
@@ -120,6 +121,7 @@ void intel_read_dp_sdp(struct intel_encoder *encoder,
 		       unsigned int type);
 bool intel_digital_port_connected(struct intel_encoder *encoder);
 void intel_dp_process_phy_request(struct intel_dp *intel_dp);
+bool intel_dp_is_vrr_capable(struct drm_connector *connector);
 
 static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
 {
-- 
2.20.1