drm/i915/icl: Support for TC North Display interrupts

The hotplug interrupts for the ports can be routed to either North
Display or South Display depending on the output mode. DP Alternate or
DP over TBT outputs will have hotplug interrupts routed to the North
Display while interrupts for legacy modes will be routed to the South
Display in PCH. This patch adds hotplug interrupt handling support for
DP Alternate mode.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
[Paulo: coding style changes]
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180616000530.5357-2-paulo.r.zanoni@intel.com

drivers/gpu/drm/i915/i915_irq.c

@@ -115,6 +115,13 @@ static const u32 hpd_bxt[HPD_NUM_PINS] = {
 	[HPD_PORT_C] = BXT_DE_PORT_HP_DDIC
 };
 
+static const u32 hpd_tc_gen11[HPD_NUM_PINS] = {
+	[HPD_PORT_C] = GEN11_TC1_HOTPLUG,
+	[HPD_PORT_D] = GEN11_TC2_HOTPLUG,
+	[HPD_PORT_E] = GEN11_TC3_HOTPLUG,
+	[HPD_PORT_F] = GEN11_TC4_HOTPLUG
+};
+
 /* IIR can theoretically queue up two events. Be paranoid. */
 #define GEN8_IRQ_RESET_NDX(type, which) do { \
 	I915_WRITE(GEN8_##type##_IMR(which), 0xffffffff); \
@@ -1549,6 +1556,22 @@ static void gen8_gt_irq_handler(struct drm_i915_private *i915,
 	}
 }
 
+static bool gen11_port_hotplug_long_detect(enum port port, u32 val)
+{
+	switch (port) {
+	case PORT_C:
+		return val & GEN11_HOTPLUG_CTL_LONG_DETECT(PORT_TC1);
+	case PORT_D:
+		return val & GEN11_HOTPLUG_CTL_LONG_DETECT(PORT_TC2);
+	case PORT_E:
+		return val & GEN11_HOTPLUG_CTL_LONG_DETECT(PORT_TC3);
+	case PORT_F:
+		return val & GEN11_HOTPLUG_CTL_LONG_DETECT(PORT_TC4);
+	default:
+		return false;
+	}
+}
+
 static bool bxt_port_hotplug_long_detect(enum port port, u32 val)
 {
 	switch (port) {
@@ -2598,6 +2621,25 @@ static void bxt_hpd_irq_handler(struct drm_i915_private *dev_priv,
 	intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
 }
 
+static void gen11_hpd_irq_handler(struct drm_i915_private *dev_priv, u32 iir)
+{
+	u32 pin_mask = 0, long_mask = 0;
+	u32 trigger_tc, dig_hotplug_reg;
+
+	trigger_tc = iir & GEN11_DE_TC_HOTPLUG_MASK;
+	if (trigger_tc) {
+		dig_hotplug_reg = I915_READ(GEN11_TC_HOTPLUG_CTL);
+		I915_WRITE(GEN11_TC_HOTPLUG_CTL, dig_hotplug_reg);
+
+		intel_get_hpd_pins(dev_priv, &pin_mask, &long_mask, trigger_tc,
+				   dig_hotplug_reg, hpd_tc_gen11,
+				   gen11_port_hotplug_long_detect);
+		intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
+	} else {
+		DRM_ERROR("Unexpected DE HPD interrupt 0x%08x\n", iir);
+	}
+}
+
 static irqreturn_t
 gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 {
@@ -2633,6 +2675,17 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 			DRM_ERROR("The master control interrupt lied (DE MISC)!\n");
 	}
 
+	if (INTEL_GEN(dev_priv) >= 11 && (master_ctl & GEN11_DE_HPD_IRQ)) {
+		iir = I915_READ(GEN11_DE_HPD_IIR);
+		if (iir) {
+			I915_WRITE(GEN11_DE_HPD_IIR, iir);
+			ret = IRQ_HANDLED;
+			gen11_hpd_irq_handler(dev_priv, iir);
+		} else {
+			DRM_ERROR("The master control interrupt lied, (DE HPD)!\n");
+		}
+	}
+
 	if (master_ctl & GEN8_DE_PORT_IRQ) {
 		iir = I915_READ(GEN8_DE_PORT_IIR);
 		if (iir) {
@@ -3513,6 +3566,7 @@ static void gen11_irq_reset(struct drm_device *dev)
 
 	GEN3_IRQ_RESET(GEN8_DE_PORT_);
 	GEN3_IRQ_RESET(GEN8_DE_MISC_);
+	GEN3_IRQ_RESET(GEN11_DE_HPD_);
 	GEN3_IRQ_RESET(GEN11_GU_MISC_);
 	GEN3_IRQ_RESET(GEN8_PCU_);
 }
@@ -3631,6 +3685,34 @@ static void ibx_hpd_irq_setup(struct drm_i915_private *dev_priv)
 	ibx_hpd_detection_setup(dev_priv);
 }
 
+static void gen11_hpd_detection_setup(struct drm_i915_private *dev_priv)
+{
+	u32 hotplug;
+
+	hotplug = I915_READ(GEN11_TC_HOTPLUG_CTL);
+	hotplug |= GEN11_HOTPLUG_CTL_ENABLE(PORT_TC1) |
+		   GEN11_HOTPLUG_CTL_ENABLE(PORT_TC2) |
+		   GEN11_HOTPLUG_CTL_ENABLE(PORT_TC3) |
+		   GEN11_HOTPLUG_CTL_ENABLE(PORT_TC4);
+	I915_WRITE(GEN11_TC_HOTPLUG_CTL, hotplug);
+}
+
+static void gen11_hpd_irq_setup(struct drm_i915_private *dev_priv)
+{
+	u32 hotplug_irqs, enabled_irqs;
+	u32 val;
+
+	enabled_irqs = intel_hpd_enabled_irqs(dev_priv, hpd_tc_gen11);
+	hotplug_irqs = GEN11_DE_TC_HOTPLUG_MASK;
+
+	val = I915_READ(GEN11_DE_HPD_IMR);
+	val &= ~hotplug_irqs;
+	I915_WRITE(GEN11_DE_HPD_IMR, val);
+	POSTING_READ(GEN11_DE_HPD_IMR);
+
+	gen11_hpd_detection_setup(dev_priv);
+}
+
 static void spt_hpd_detection_setup(struct drm_i915_private *dev_priv)
 {
 	u32 val, hotplug;
@@ -4004,10 +4086,17 @@ static void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
 	GEN3_IRQ_INIT(GEN8_DE_PORT_, ~de_port_masked, de_port_enables);
 	GEN3_IRQ_INIT(GEN8_DE_MISC_, ~de_misc_masked, de_misc_masked);
 
-	if (IS_GEN9_LP(dev_priv))
+	if (INTEL_GEN(dev_priv) >= 11) {
+		u32 de_hpd_masked = 0;
+		u32 de_hpd_enables = GEN11_DE_TC_HOTPLUG_MASK;
+
+		GEN3_IRQ_INIT(GEN11_DE_HPD_, ~de_hpd_masked, de_hpd_enables);
+		gen11_hpd_detection_setup(dev_priv);
+	} else if (IS_GEN9_LP(dev_priv)) {
 		bxt_hpd_detection_setup(dev_priv);
-	else if (IS_BROADWELL(dev_priv))
+	} else if (IS_BROADWELL(dev_priv)) {
 		ilk_hpd_detection_setup(dev_priv);
+	}
 }
 
 static int gen8_irq_postinstall(struct drm_device *dev)
@@ -4529,7 +4618,7 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
 		dev->driver->irq_uninstall = gen11_irq_reset;
 		dev->driver->enable_vblank = gen8_enable_vblank;
 		dev->driver->disable_vblank = gen8_disable_vblank;
-		dev_priv->display.hpd_irq_setup = spt_hpd_irq_setup;
+		dev_priv->display.hpd_irq_setup = gen11_hpd_irq_setup;
 	} else if (INTEL_GEN(dev_priv) >= 8) {
 		dev->driver->irq_handler = gen8_irq_handler;
 		dev->driver->irq_preinstall = gen8_irq_reset;

drivers/gpu/drm/i915/i915_reg.h

@@ -7079,11 +7079,31 @@ enum {
 #define  GEN11_AUDIO_CODEC_IRQ		(1 << 24)
 #define  GEN11_DE_PCH_IRQ		(1 << 23)
 #define  GEN11_DE_MISC_IRQ		(1 << 22)
+#define  GEN11_DE_HPD_IRQ		(1 << 21)
 #define  GEN11_DE_PORT_IRQ		(1 << 20)
 #define  GEN11_DE_PIPE_C		(1 << 18)
 #define  GEN11_DE_PIPE_B		(1 << 17)
 #define  GEN11_DE_PIPE_A		(1 << 16)
 
+#define GEN11_DE_HPD_ISR		_MMIO(0x44470)
+#define GEN11_DE_HPD_IMR		_MMIO(0x44474)
+#define GEN11_DE_HPD_IIR		_MMIO(0x44478)
+#define GEN11_DE_HPD_IER		_MMIO(0x4447c)
+#define  GEN11_TC4_HOTPLUG			(1 << 19)
+#define  GEN11_TC3_HOTPLUG			(1 << 18)
+#define  GEN11_TC2_HOTPLUG			(1 << 17)
+#define  GEN11_TC1_HOTPLUG			(1 << 16)
+#define  GEN11_DE_TC_HOTPLUG_MASK		(GEN11_TC4_HOTPLUG | \
+						 GEN11_TC3_HOTPLUG | \
+						 GEN11_TC2_HOTPLUG | \
+						 GEN11_TC1_HOTPLUG)
+
+#define GEN11_TC_HOTPLUG_CTL				_MMIO(0x44038)
+#define  GEN11_HOTPLUG_CTL_ENABLE(tc_port)		(8 << (tc_port) * 4)
+#define  GEN11_HOTPLUG_CTL_LONG_DETECT(tc_port)		(2 << (tc_port) * 4)
+#define  GEN11_HOTPLUG_CTL_SHORT_DETECT(tc_port)	(1 << (tc_port) * 4)
+#define  GEN11_HOTPLUG_CTL_NO_DETECT(tc_port)		(0 << (tc_port) * 4)
+
 #define GEN11_GT_INTR_DW0		_MMIO(0x190018)
 #define  GEN11_CSME			(31)
 #define  GEN11_GUNIT			(28)