drm/i915/ehl: Don't forget to handle port C's hotplug interrupts

We're mostly re-using ICL's interrupt handling on EHL, but we still need
to remember to account for the extra combo port that EHL has.  Use TGP's
mask (which includes combo port C) rather than ICP's mask when
appropriate.  Let's also skip reading TC-specific registers on this
platform since EHL doesn't have any TC ports.

v2: Base setup of SHOTPLUG_CTL_TC on whether the tc pin mask is non-zero
    rather than performing another PCH type check.  (Jose)

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190730220553.15300-1-matthew.d.roper@intel.com

drivers/gpu/drm/i915/i915_irq.c

@@ -1746,6 +1746,8 @@ static bool icp_ddi_port_hotplug_long_detect(enum hpd_pin pin, u32 val)
 		return val & ICP_DDIA_HPD_LONG_DETECT;
 	case HPD_PORT_B:
 		return val & ICP_DDIB_HPD_LONG_DETECT;
+	case HPD_PORT_C:
+		return val & TGP_DDIC_HPD_LONG_DETECT;
 	default:
 		return false;
 	}
@@ -2605,10 +2607,18 @@ static void cpt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
 static void icp_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir,
 			    const u32 *pins)
 {
-	u32 ddi_hotplug_trigger = pch_iir & SDE_DDI_MASK_ICP;
-	u32 tc_hotplug_trigger = pch_iir & SDE_TC_MASK_ICP;
+	u32 ddi_hotplug_trigger;
+	u32 tc_hotplug_trigger;
 	u32 pin_mask = 0, long_mask = 0;
 
+	if (HAS_PCH_MCC(dev_priv)) {
+		ddi_hotplug_trigger = pch_iir & SDE_DDI_MASK_TGP;
+		tc_hotplug_trigger = 0;
+	} else {
+		ddi_hotplug_trigger = pch_iir & SDE_DDI_MASK_ICP;
+		tc_hotplug_trigger = pch_iir & SDE_TC_MASK_ICP;
+	}
+
 	if (ddi_hotplug_trigger) {
 		u32 dig_hotplug_reg;
 
@@ -3920,9 +3930,11 @@ static void icp_hpd_detection_setup(struct drm_i915_private *dev_priv,
 	hotplug |= ddi_hotplug_enable_mask;
 	I915_WRITE(SHOTPLUG_CTL_DDI, hotplug);
 
-	hotplug = I915_READ(SHOTPLUG_CTL_TC);
-	hotplug |= tc_hotplug_enable_mask;
-	I915_WRITE(SHOTPLUG_CTL_TC, hotplug);
+	if (tc_hotplug_enable_mask) {
+		hotplug = I915_READ(SHOTPLUG_CTL_TC);
+		hotplug |= tc_hotplug_enable_mask;
+		I915_WRITE(SHOTPLUG_CTL_TC, hotplug);
+	}
 }
 
 static void icp_hpd_irq_setup(struct drm_i915_private *dev_priv)
@@ -3938,6 +3950,18 @@ static void icp_hpd_irq_setup(struct drm_i915_private *dev_priv)
 				ICP_TC_HPD_ENABLE_MASK);
 }
 
+static void mcc_hpd_irq_setup(struct drm_i915_private *dev_priv)
+{
+	u32 hotplug_irqs, enabled_irqs;
+
+	hotplug_irqs = SDE_DDI_MASK_TGP;
+	enabled_irqs = intel_hpd_enabled_irqs(dev_priv, hpd_mcc);
+
+	ibx_display_interrupt_update(dev_priv, hotplug_irqs, enabled_irqs);
+
+	icp_hpd_detection_setup(dev_priv, TGP_DDI_HPD_ENABLE_MASK, 0);
+}
+
 static void tgp_hpd_irq_setup(struct drm_i915_private *dev_priv)
 {
 	u32 hotplug_irqs, enabled_irqs;
@@ -4442,6 +4466,8 @@ static void icp_irq_postinstall(struct drm_i915_private *dev_priv)
 	if (HAS_PCH_TGP(dev_priv))
 		icp_hpd_detection_setup(dev_priv, TGP_DDI_HPD_ENABLE_MASK,
 					TGP_TC_HPD_ENABLE_MASK);
+	else if (HAS_PCH_MCC(dev_priv))
+		icp_hpd_detection_setup(dev_priv, TGP_DDI_HPD_ENABLE_MASK, 0);
 	else
 		icp_hpd_detection_setup(dev_priv, ICP_DDI_HPD_ENABLE_MASK,
 					ICP_TC_HPD_ENABLE_MASK);
@@ -4974,7 +5000,10 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
 		if (I915_HAS_HOTPLUG(dev_priv))
 			dev_priv->display.hpd_irq_setup = i915_hpd_irq_setup;
 	} else {
-		if (INTEL_GEN(dev_priv) >= 11)
+		if (HAS_PCH_MCC(dev_priv))
+			/* EHL doesn't need most of gen11_hpd_irq_setup */
+			dev_priv->display.hpd_irq_setup = mcc_hpd_irq_setup;
+		else if (INTEL_GEN(dev_priv) >= 11)
 			dev_priv->display.hpd_irq_setup = gen11_hpd_irq_setup;
 		else if (IS_GEN9_LP(dev_priv))
 			dev_priv->display.hpd_irq_setup = bxt_hpd_irq_setup;