From 237ed86c693d8a8e4db476976aeb30df4deac74b Mon Sep 17 00:00:00 2001 From: Sonika Jindal Date: Tue, 15 Sep 2015 09:44:20 +0530 Subject: [PATCH] drm/i915: Check live status before reading edid The Bspec is very clear that Live status must be checked about before trying to read EDID over DDC channel. This patch makes sure that HDMI EDID is read only when live status is up. The live status doesn't seem to perform very consistent across various platforms when tested with different monitors. The reason behind that is some monitors are late to provide right voltage to set live_status up. So, after getting the interrupt, for a small duration, live status reg fluctuates, and then settles down showing the correct staus. This is explained here in, in a rough way: HPD line ________________ |\ T1 = Monitor Hotplug causing IRQ | \______________________________________ | | | | | | T2 = Live status is stable | | _____________________________________ | | /| Live status _____________|_|/ | | | | | | | | | | T0 T1 T2 (Between T1 and T2 Live status fluctuates or can be even low, depending on the monitor) After several experiments, we have concluded that a max delay of 30ms is enough to allow the live status to settle down with most of the monitors. This total delay of 30ms has been split into a resolution of 3 retries of 10ms each, for the better cases. This delay is kept at 30ms, keeping in consideration that, HDCP compliance expect the HPD handler to respond a plug out in 100ms, by disabling port. v2: Adding checks for VLV/CHV as well. Reusing old ibx and g4x functions to check digital port status. Adding a separate function to get bxt live status (Daniel) v3: Using intel_encoder->hpd_pin to check the live status (Siva) Moving the live status read to intel_hdmi_probe and passing parameter to read/not to read the edid. (me) v4: * Added live status check for all platforms using intel_digital_port_connected. * Rebased on top of Jani's DP cleanup series * Some monitors take time in setting the live status. So retry for few times if this is a connect HPD v5: Removed extra "drm/i915" from commit message. Adding Shashank's sob which was missed. v6: Drop the (!detect_edid && !live_status check) check because for DDI ports which are enumerated as hdmi as well as DP, we don't have a mechanism to differentiate between DP and hdmi inside the encoder's hot_plug. This leads to call to the hdmi's hot_plug hook for DP as well as hdmi which leads to issues during unplug because of the above check. v7: Make intel_digital_port_connected global in this patch, some reformatting of while loop, adding a print when live status is not up. (Rodrigo) v8: Rebase it on nightly which involved skipping the hot_plug hook for now and letting the live_status check happen in detect until the hpd handling part is finalized (Daniel) Signed-off-by: Shashank Sharma Signed-off-by: Sonika Jindal Reviewed-by: Rodrigo Vivi Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_dp.c | 2 +- drivers/gpu/drm/i915/intel_drv.h | 2 ++ drivers/gpu/drm/i915/intel_hdmi.c | 28 +++++++++++++++++++++------- 3 files changed, 24 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 9700f774dc6c..02401a397dcc 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4672,7 +4672,7 @@ static bool bxt_digital_port_connected(struct drm_i915_private *dev_priv, * * Return %true if @port is connected, %false otherwise. */ -static bool intel_digital_port_connected(struct drm_i915_private *dev_priv, +bool intel_digital_port_connected(struct drm_i915_private *dev_priv, struct intel_digital_port *port) { if (HAS_PCH_IBX(dev_priv)) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 8760814e81f6..394018ead36b 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1218,6 +1218,8 @@ void intel_edp_drrs_disable(struct intel_dp *intel_dp); void intel_edp_drrs_invalidate(struct drm_device *dev, unsigned frontbuffer_bits); void intel_edp_drrs_flush(struct drm_device *dev, unsigned frontbuffer_bits); +bool intel_digital_port_connected(struct drm_i915_private *dev_priv, + struct intel_digital_port *port); void hsw_dp_set_ddi_pll_sel(struct intel_crtc_state *pipe_config); /* intel_dp_mst.c */ diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c index e978c59dc243..bb33c66b0b12 100644 --- a/drivers/gpu/drm/i915/intel_hdmi.c +++ b/drivers/gpu/drm/i915/intel_hdmi.c @@ -1329,22 +1329,23 @@ intel_hdmi_unset_edid(struct drm_connector *connector) } static bool -intel_hdmi_set_edid(struct drm_connector *connector) +intel_hdmi_set_edid(struct drm_connector *connector, bool force) { struct drm_i915_private *dev_priv = to_i915(connector->dev); struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector); struct intel_encoder *intel_encoder = &hdmi_to_dig_port(intel_hdmi)->base; enum intel_display_power_domain power_domain; - struct edid *edid; + struct edid *edid = NULL; bool connected = false; power_domain = intel_display_port_power_domain(intel_encoder); intel_display_power_get(dev_priv, power_domain); - edid = drm_get_edid(connector, - intel_gmbus_get_adapter(dev_priv, - intel_hdmi->ddc_bus)); + if (force) + edid = drm_get_edid(connector, + intel_gmbus_get_adapter(dev_priv, + intel_hdmi->ddc_bus)); intel_display_power_put(dev_priv, power_domain); @@ -1372,13 +1373,26 @@ static enum drm_connector_status intel_hdmi_detect(struct drm_connector *connector, bool force) { enum drm_connector_status status; + struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector); + struct drm_i915_private *dev_priv = to_i915(connector->dev); + bool live_status = false; + unsigned int retry = 3; DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, connector->name); + while (!live_status && --retry) { + live_status = intel_digital_port_connected(dev_priv, + hdmi_to_dig_port(intel_hdmi)); + mdelay(10); + } + + if (!live_status) + DRM_DEBUG_KMS("Live status not up!"); + intel_hdmi_unset_edid(connector); - if (intel_hdmi_set_edid(connector)) { + if (intel_hdmi_set_edid(connector, live_status)) { struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector); hdmi_to_dig_port(intel_hdmi)->base.type = INTEL_OUTPUT_HDMI; @@ -1402,7 +1416,7 @@ intel_hdmi_force(struct drm_connector *connector) if (connector->status != connector_status_connected) return; - intel_hdmi_set_edid(connector); + intel_hdmi_set_edid(connector, true); hdmi_to_dig_port(intel_hdmi)->base.type = INTEL_OUTPUT_HDMI; } -- 2.20.1