drm/i915/xe2lpd: Add support for HPD

Hotplug setup for Xe2_LPD differs from Xe_LPD+ by the fact that the
extra programming for hotplug inversion and DDI HPD filter duration is
not necessary anymore. As mtp_hpd_irq_setup() is reasonably small,
prefer to fork it into a new function for Xe2_LPD instead of adding a
platform check.

v2: Add extra bspec reference and fix missing else (Matt Roper)

BSpec: 68970, 69940
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230919192128.2045154-16-lucas.demarchi@intel.com

drivers/gpu/drm/i915/display/intel_hotplug_irq.c

@@ -163,7 +163,9 @@ static void intel_hpd_init_pins(struct drm_i915_private *dev_priv)
 	    (!HAS_PCH_SPLIT(dev_priv) || HAS_PCH_NOP(dev_priv)))
 		return;
 
-	if (INTEL_PCH_TYPE(dev_priv) >= PCH_DG1)
+	if (INTEL_PCH_TYPE(dev_priv) >= PCH_LNL)
+		hpd->pch_hpd = hpd_mtp;
+	else if (INTEL_PCH_TYPE(dev_priv) >= PCH_DG1)
 		hpd->pch_hpd = hpd_sde_dg1;
 	else if (INTEL_PCH_TYPE(dev_priv) >= PCH_MTP)
 		hpd->pch_hpd = hpd_mtp;
@@ -1063,6 +1065,19 @@ static void mtp_hpd_irq_setup(struct drm_i915_private *i915)
 	mtp_tc_hpd_detection_setup(i915);
 }
 
+static void xe2lpd_sde_hpd_irq_setup(struct drm_i915_private *i915)
+{
+	u32 hotplug_irqs, enabled_irqs;
+
+	enabled_irqs = intel_hpd_enabled_irqs(i915, i915->display.hotplug.pch_hpd);
+	hotplug_irqs = intel_hpd_hotplug_irqs(i915, i915->display.hotplug.pch_hpd);
+
+	ibx_display_interrupt_update(i915, hotplug_irqs, enabled_irqs);
+
+	mtp_ddi_hpd_detection_setup(i915);
+	mtp_tc_hpd_detection_setup(i915);
+}
+
 static bool is_xelpdp_pica_hpd_pin(enum hpd_pin hpd_pin)
 {
 	return hpd_pin >= HPD_PORT_TC1 && hpd_pin <= HPD_PORT_TC4;
@@ -1122,7 +1137,9 @@ static void xelpdp_hpd_irq_setup(struct drm_i915_private *i915)
 
 	xelpdp_pica_hpd_detection_setup(i915);
 
-	if (INTEL_PCH_TYPE(i915) >= PCH_MTP)
+	if (INTEL_PCH_TYPE(i915) >= PCH_LNL)
+		xe2lpd_sde_hpd_irq_setup(i915);
+	else if (INTEL_PCH_TYPE(i915) >= PCH_MTP)
 		mtp_hpd_irq_setup(i915);
 }