[PATCH 7/7] drm/i915: Add display hotplug event on Ironlake

[Stefan Bader]

From: Zhenyu Wang <zhenyuw at linux.intel.com>

commit c650156af34bffa3d3a62c9fe26eee595aab3fd1 upstream

Enable display hotplug irqs from Ibex Peak (PCH).

Signed-off-by: Zhenyu Wang <zhenyuw at linux.intel.com>
Signed-off-by: Eric Anholt <eric at anholt.net>
Signed-off-by: Stefan Bader <stefan.bader at canonical.com>
---
 drivers/gpu/drm/i915/i915_drv.h |    2 ++
 drivers/gpu/drm/i915/i915_irq.c |   35 +++++++++++++++++++++++++++++++----
 drivers/gpu/drm/i915/i915_reg.h |    1 +
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 26583d9..9919f9f 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -188,6 +188,8 @@ typedef struct drm_i915_private {
 	u32 gt_irq_mask_reg;
 	u32 gt_irq_enable_reg;
 	u32 de_irq_enable_reg;
+	u32 pch_irq_mask_reg;
+	u32 pch_irq_enable_reg;
 
 	u32 hotplug_supported_mask;
 	struct work_struct hotplug_work;
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index b3bbd4c..5caf737 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -267,8 +267,8 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 	int ret = IRQ_NONE;
-	u32 de_iir, gt_iir, de_ier;
-	u32 new_de_iir, new_gt_iir;
+	u32 de_iir, gt_iir, de_ier, pch_iir;
+	u32 new_de_iir, new_gt_iir, new_pch_iir;
 	struct drm_i915_master_private *master_priv;
 
 	/* disable master interrupt before clearing iir  */
@@ -278,13 +278,18 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
 
 	de_iir = I915_READ(DEIIR);
 	gt_iir = I915_READ(GTIIR);
+	pch_iir = I915_READ(SDEIIR);
 
 	for (;;) {
-		if (de_iir == 0 && gt_iir == 0)
+		if (de_iir == 0 && gt_iir == 0 && pch_iir == 0)
 			break;
 
 		ret = IRQ_HANDLED;
 
+		/* should clear PCH hotplug event before clear CPU irq */
+		I915_WRITE(SDEIIR, pch_iir);
+		new_pch_iir = I915_READ(SDEIIR);
+
 		I915_WRITE(DEIIR, de_iir);
 		new_de_iir = I915_READ(DEIIR);
 		I915_WRITE(GTIIR, gt_iir);
@@ -305,8 +310,15 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
 		if (de_iir & DE_GSE)
 			ironlake_opregion_gse_intr(dev);
 
+		/* check event from PCH */
+		if ((de_iir & DE_PCH_EVENT) &&
+			(pch_iir & SDE_HOTPLUG_MASK)) {
+			queue_work(dev_priv->wq, &dev_priv->hotplug_work);
+		}
+
 		de_iir = new_de_iir;
 		gt_iir = new_gt_iir;
+		pch_iir = new_pch_iir;
 	}
 
 	I915_WRITE(DEIER, de_ier);
@@ -902,14 +914,21 @@ static void igdng_irq_preinstall(struct drm_device *dev)
 	I915_WRITE(GTIMR, 0xffffffff);
 	I915_WRITE(GTIER, 0x0);
 	(void) I915_READ(GTIER);
+
+	/* south display irq */
+	I915_WRITE(SDEIMR, 0xffffffff);
+	I915_WRITE(SDEIER, 0x0);
+	(void) I915_READ(SDEIER);
 }
 
 static int igdng_irq_postinstall(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 	/* enable kind of interrupts always enabled */
-	u32 display_mask = DE_MASTER_IRQ_CONTROL | DE_GSE /*| DE_PCH_EVENT */;
+	u32 display_mask = DE_MASTER_IRQ_CONTROL | DE_GSE | DE_PCH_EVENT;
 	u32 render_mask = GT_USER_INTERRUPT;
+	u32 hotplug_mask = SDE_CRT_HOTPLUG | SDE_PORTB_HOTPLUG |
+			   SDE_PORTC_HOTPLUG | SDE_PORTD_HOTPLUG;
 
 	dev_priv->irq_mask_reg = ~display_mask;
 	dev_priv->de_irq_enable_reg = display_mask;
@@ -929,6 +948,14 @@ static int igdng_irq_postinstall(struct drm_device *dev)
 	I915_WRITE(GTIER, dev_priv->gt_irq_enable_reg);
 	(void) I915_READ(GTIER);
 
+	dev_priv->pch_irq_mask_reg = ~hotplug_mask;
+	dev_priv->pch_irq_enable_reg = hotplug_mask;
+
+	I915_WRITE(SDEIIR, I915_READ(SDEIIR));
+	I915_WRITE(SDEIMR, dev_priv->pch_irq_mask_reg);
+	I915_WRITE(SDEIER, dev_priv->pch_irq_enable_reg);
+	(void) I915_READ(SDEIER);
+
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 9917749..29633cc 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1939,6 +1939,7 @@
 #define SDE_PORTC_HOTPLUG       (1 << 9)
 #define SDE_PORTB_HOTPLUG       (1 << 8)
 #define SDE_SDVOB_HOTPLUG       (1 << 6)
+#define SDE_HOTPLUG_MASK	(0xf << 8)
 
 #define SDEISR  0xc4000
 #define SDEIMR  0xc4004
-- 
1.6.3.3