releases/3.17.3/drm-i915-properly-reenable-gen8-pipe-irqs.patch

From 1180e20606fd7c5d76dc5b2a1594fa51ba5a0f31 Mon Sep 17 00:00:00 2001
From: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date: Tue, 7 Oct 2014 18:02:52 -0300
Subject: drm/i915: properly reenable gen8 pipe IRQs
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From: Paulo Zanoni <paulo.r.zanoni@intel.com>

commit 1180e20606fd7c5d76dc5b2a1594fa51ba5a0f31 upstream.

We were missing the pipe B/C vblank bits! Take a look at
gen8_de_irq_postinstall for a comparison.

This should fix a bunch of IGT tests.

There are a few more things we could improve on this code, but this
should be the minimal fix to unblock us.

v2: s/extra_iir/extra_ier/ because IIR doesn't make sense (Ville)

Bugzilla:https://bugs.freedesktop.org/show_bug.cgi?id=83640
Testcase: igt/*
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/i915/i915_irq.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -3482,12 +3482,13 @@ static void gen8_irq_reset(struct drm_de
 void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv)
 {
 	unsigned long irqflags;
+	uint32_t extra_ier = GEN8_PIPE_VBLANK | GEN8_PIPE_FIFO_UNDERRUN;
 
 	spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
 	GEN8_IRQ_INIT_NDX(DE_PIPE, PIPE_B, dev_priv->de_irq_mask[PIPE_B],
-			  ~dev_priv->de_irq_mask[PIPE_B]);
+			  ~dev_priv->de_irq_mask[PIPE_B] | extra_ier);
 	GEN8_IRQ_INIT_NDX(DE_PIPE, PIPE_C, dev_priv->de_irq_mask[PIPE_C],
-			  ~dev_priv->de_irq_mask[PIPE_C]);
+			  ~dev_priv->de_irq_mask[PIPE_C] | extra_ier);
 	spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
 }