drm/i915/icp: Add Interrupt Support

This patch addresses Interrupts from south display engine (SDE).

ICP has two registers - SHOTPLUG_CTL_DDI and SHOTPLUG_CTL_TC.
Introduce these registers and their intended values.

Introduce icp_irq_handler().

The icp_irq_postinstall() takes care of
enabling all PCH interrupt sources, to unmask
them as needed with SDEIMR, as is done
done by ibx_irq_pre_postinstall() for earlier platforms.
We do not need to explicitly call the ibx_irq_pre_postinstall().

Also, while changing these,
s/CPT/PPT/CPT-CNP comment.

v2:
- remove redundant register defines.(Lucas)
- Change register names to be more consistent with
previous platforms (Lucas)

v3:
-Reorder bit defines to a more appropriate location.
 Change the comments. Confirm in the commit message that
 icp_irq_postinstall() need not go to
 ibx_irq_pre_postinstall() and ibx_irq_postinstall()
 as in earlier platforms. (Paulo)

Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
[Paulo: coding style bikesheds and rebases].
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1530046343-30649-1-git-send-email-anusha.srivatsa@intel.com

drivers/gpu/drm/i915/i915_irq.c

@@ -122,6 +122,15 @@ static const u32 hpd_gen11[HPD_NUM_PINS] = {
 	[HPD_PORT_F] = GEN11_TC4_HOTPLUG | GEN11_TBT4_HOTPLUG
 };
 
+static const u32 hpd_icp[HPD_NUM_PINS] = {
+	[HPD_PORT_A] = SDE_DDIA_HOTPLUG_ICP,
+	[HPD_PORT_B] = SDE_DDIB_HOTPLUG_ICP,
+	[HPD_PORT_C] = SDE_TC1_HOTPLUG_ICP,
+	[HPD_PORT_D] = SDE_TC2_HOTPLUG_ICP,
+	[HPD_PORT_E] = SDE_TC3_HOTPLUG_ICP,
+	[HPD_PORT_F] = SDE_TC4_HOTPLUG_ICP
+};
+
 /* IIR can theoretically queue up two events. Be paranoid. */
 #define GEN8_IRQ_RESET_NDX(type, which) do { \
 	I915_WRITE(GEN8_##type##_IMR(which), 0xffffffff); \
@@ -1586,6 +1595,34 @@ static bool bxt_port_hotplug_long_detect(enum port port, u32 val)
 	}
 }
 
+static bool icp_ddi_port_hotplug_long_detect(enum port port, u32 val)
+{
+	switch (port) {
+	case PORT_A:
+		return val & ICP_DDIA_HPD_LONG_DETECT;
+	case PORT_B:
+		return val & ICP_DDIB_HPD_LONG_DETECT;
+	default:
+		return false;
+	}
+}
+
+static bool icp_tc_port_hotplug_long_detect(enum port port, u32 val)
+{
+	switch (port) {
+	case PORT_C:
+		return val & ICP_TC_HPD_LONG_DETECT(PORT_TC1);
+	case PORT_D:
+		return val & ICP_TC_HPD_LONG_DETECT(PORT_TC2);
+	case PORT_E:
+		return val & ICP_TC_HPD_LONG_DETECT(PORT_TC3);
+	case PORT_F:
+		return val & ICP_TC_HPD_LONG_DETECT(PORT_TC4);
+	default:
+		return false;
+	}
+}
+
 static bool spt_port_hotplug2_long_detect(enum port port, u32 val)
 {
 	switch (port) {
@@ -2385,6 +2422,43 @@ static void cpt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
 		cpt_serr_int_handler(dev_priv);
 }
 
+static void icp_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
+{
+	u32 ddi_hotplug_trigger = pch_iir & SDE_DDI_MASK_ICP;
+	u32 tc_hotplug_trigger = pch_iir & SDE_TC_MASK_ICP;
+	u32 pin_mask = 0, long_mask = 0;
+
+	if (ddi_hotplug_trigger) {
+		u32 dig_hotplug_reg;
+
+		dig_hotplug_reg = I915_READ(SHOTPLUG_CTL_DDI);
+		I915_WRITE(SHOTPLUG_CTL_DDI, dig_hotplug_reg);
+
+		intel_get_hpd_pins(dev_priv, &pin_mask, &long_mask,
+				   ddi_hotplug_trigger,
+				   dig_hotplug_reg, hpd_icp,
+				   icp_ddi_port_hotplug_long_detect);
+	}
+
+	if (tc_hotplug_trigger) {
+		u32 dig_hotplug_reg;
+
+		dig_hotplug_reg = I915_READ(SHOTPLUG_CTL_TC);
+		I915_WRITE(SHOTPLUG_CTL_TC, dig_hotplug_reg);
+
+		intel_get_hpd_pins(dev_priv, &pin_mask, &long_mask,
+				   tc_hotplug_trigger,
+				   dig_hotplug_reg, hpd_icp,
+				   icp_tc_port_hotplug_long_detect);
+	}
+
+	if (pin_mask)
+		intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
+
+	if (pch_iir & SDE_GMBUS_ICP)
+		gmbus_irq_handler(dev_priv);
+}
+
 static void spt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
 {
 	u32 hotplug_trigger = pch_iir & SDE_HOTPLUG_MASK_SPT &
@@ -2804,8 +2878,11 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 			I915_WRITE(SDEIIR, iir);
 			ret = IRQ_HANDLED;
 
-			if (HAS_PCH_SPT(dev_priv) || HAS_PCH_KBP(dev_priv) ||
-			    HAS_PCH_CNP(dev_priv))
+			if (HAS_PCH_ICP(dev_priv))
+				icp_irq_handler(dev_priv, iir);
+			else if (HAS_PCH_SPT(dev_priv) ||
+				 HAS_PCH_KBP(dev_priv) ||
+				 HAS_PCH_CNP(dev_priv))
 				spt_irq_handler(dev_priv, iir);
 			else
 				cpt_irq_handler(dev_priv, iir);
@@ -3584,6 +3661,9 @@ static void gen11_irq_reset(struct drm_device *dev)
 	GEN3_IRQ_RESET(GEN11_DE_HPD_);
 	GEN3_IRQ_RESET(GEN11_GU_MISC_);
 	GEN3_IRQ_RESET(GEN8_PCU_);
+
+	if (HAS_PCH_ICP(dev_priv))
+		GEN3_IRQ_RESET(SDE);
 }
 
 void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
@@ -3700,6 +3780,35 @@ static void ibx_hpd_irq_setup(struct drm_i915_private *dev_priv)
 	ibx_hpd_detection_setup(dev_priv);
 }
 
+static void icp_hpd_detection_setup(struct drm_i915_private *dev_priv)
+{
+	u32 hotplug;
+
+	hotplug = I915_READ(SHOTPLUG_CTL_DDI);
+	hotplug |= ICP_DDIA_HPD_ENABLE |
+		   ICP_DDIB_HPD_ENABLE;
+	I915_WRITE(SHOTPLUG_CTL_DDI, hotplug);
+
+	hotplug = I915_READ(SHOTPLUG_CTL_TC);
+	hotplug |= ICP_TC_HPD_ENABLE(PORT_TC1) |
+		   ICP_TC_HPD_ENABLE(PORT_TC2) |
+		   ICP_TC_HPD_ENABLE(PORT_TC3) |
+		   ICP_TC_HPD_ENABLE(PORT_TC4);
+	I915_WRITE(SHOTPLUG_CTL_TC, hotplug);
+}
+
+static void icp_hpd_irq_setup(struct drm_i915_private *dev_priv)
+{
+	u32 hotplug_irqs, enabled_irqs;
+
+	hotplug_irqs = SDE_DDI_MASK_ICP | SDE_TC_MASK_ICP;
+	enabled_irqs = intel_hpd_enabled_irqs(dev_priv, hpd_icp);
+
+	ibx_display_interrupt_update(dev_priv, hotplug_irqs, enabled_irqs);
+
+	icp_hpd_detection_setup(dev_priv);
+}
+
 static void gen11_hpd_detection_setup(struct drm_i915_private *dev_priv)
 {
 	u32 hotplug;
@@ -3733,6 +3842,9 @@ static void gen11_hpd_irq_setup(struct drm_i915_private *dev_priv)
 	POSTING_READ(GEN11_DE_HPD_IMR);
 
 	gen11_hpd_detection_setup(dev_priv);
+
+	if (HAS_PCH_ICP(dev_priv))
+		icp_hpd_irq_setup(dev_priv);
 }
 
 static void spt_hpd_detection_setup(struct drm_i915_private *dev_priv)
@@ -4168,11 +4280,29 @@ static void gen11_gt_irq_postinstall(struct drm_i915_private *dev_priv)
 	I915_WRITE(GEN11_GPM_WGBOXPERF_INTR_MASK,  ~0);
 }
 
+static void icp_irq_postinstall(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	u32 mask = SDE_GMBUS_ICP;
+
+	WARN_ON(I915_READ(SDEIER) != 0);
+	I915_WRITE(SDEIER, 0xffffffff);
+	POSTING_READ(SDEIER);
+
+	gen3_assert_iir_is_zero(dev_priv, SDEIIR);
+	I915_WRITE(SDEIMR, ~mask);
+
+	icp_hpd_detection_setup(dev_priv);
+}
+
 static int gen11_irq_postinstall(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 gu_misc_masked = GEN11_GU_MISC_GSE;
 
+	if (HAS_PCH_ICP(dev_priv))
+		icp_irq_postinstall(dev);
+
 	gen11_gt_irq_postinstall(dev_priv);
 	gen8_de_irq_postinstall(dev_priv);
 

drivers/gpu/drm/i915/i915_reg.h

@@ -7462,7 +7462,7 @@ enum {
 #define SDE_TRANSA_FIFO_UNDER	(1 << 0)
 #define SDE_TRANS_MASK		(0x3f)
 
-/* south display engine interrupt: CPT/PPT */
+/* south display engine interrupt: CPT - CNP */
 #define SDE_AUDIO_POWER_D_CPT	(1 << 31)
 #define SDE_AUDIO_POWER_C_CPT	(1 << 30)
 #define SDE_AUDIO_POWER_B_CPT	(1 << 29)
@@ -7510,6 +7510,21 @@ enum {
 				 SDE_FDI_RXB_CPT | \
 				 SDE_FDI_RXA_CPT)
 
+/* south display engine interrupt: ICP */
+#define SDE_TC4_HOTPLUG_ICP		(1 << 27)
+#define SDE_TC3_HOTPLUG_ICP		(1 << 26)
+#define SDE_TC2_HOTPLUG_ICP		(1 << 25)
+#define SDE_TC1_HOTPLUG_ICP		(1 << 24)
+#define SDE_GMBUS_ICP			(1 << 23)
+#define SDE_DDIB_HOTPLUG_ICP		(1 << 17)
+#define SDE_DDIA_HOTPLUG_ICP		(1 << 16)
+#define SDE_DDI_MASK_ICP		(SDE_DDIB_HOTPLUG_ICP |	\
+					 SDE_DDIA_HOTPLUG_ICP)
+#define SDE_TC_MASK_ICP			(SDE_TC4_HOTPLUG_ICP |	\
+					 SDE_TC3_HOTPLUG_ICP |	\
+					 SDE_TC2_HOTPLUG_ICP |	\
+					 SDE_TC1_HOTPLUG_ICP)
+
 #define SDEISR  _MMIO(0xc4000)
 #define SDEIMR  _MMIO(0xc4004)
 #define SDEIIR  _MMIO(0xc4008)
@@ -7570,6 +7585,30 @@ enum {
 #define  PORTE_HOTPLUG_SHORT_DETECT	(1 << 0)
 #define  PORTE_HOTPLUG_LONG_DETECT	(2 << 0)
 
+/* This register is a reuse of PCH_PORT_HOTPLUG register. The
+ * functionality covered in PCH_PORT_HOTPLUG is split into
+ * SHOTPLUG_CTL_DDI and SHOTPLUG_CTL_TC.
+ */
+
+#define SHOTPLUG_CTL_DDI			_MMIO(0xc4030)
+#define   ICP_DDIB_HPD_ENABLE			(1 << 7)
+#define   ICP_DDIB_HPD_STATUS_MASK		(3 << 4)
+#define   ICP_DDIB_HPD_NO_DETECT		(0 << 4)
+#define   ICP_DDIB_HPD_SHORT_DETECT		(1 << 4)
+#define   ICP_DDIB_HPD_LONG_DETECT		(2 << 4)
+#define   ICP_DDIB_HPD_SHORT_LONG_DETECT	(3 << 4)
+#define   ICP_DDIA_HPD_ENABLE			(1 << 3)
+#define   ICP_DDIA_HPD_STATUS_MASK		(3 << 0)
+#define   ICP_DDIA_HPD_NO_DETECT		(0 << 0)
+#define   ICP_DDIA_HPD_SHORT_DETECT		(1 << 0)
+#define   ICP_DDIA_HPD_LONG_DETECT		(2 << 0)
+#define   ICP_DDIA_HPD_SHORT_LONG_DETECT	(3 << 0)
+
+#define SHOTPLUG_CTL_TC				_MMIO(0xc4034)
+#define   ICP_TC_HPD_ENABLE(tc_port)		(8 << (tc_port) * 4)
+#define   ICP_TC_HPD_LONG_DETECT(tc_port)	(2 << (tc_port) * 4)
+#define   ICP_TC_HPD_SHORT_DETECT(tc_port)	(1 << (tc_port) * 4)
+
 #define PCH_GPIOA               _MMIO(0xc5010)
 #define PCH_GPIOB               _MMIO(0xc5014)
 #define PCH_GPIOC               _MMIO(0xc5018)