[PATCH 19/19] drm/i915: only enable HWSTAM interrupts on postinstall on ILK+

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

We should only enable interrupts at postinstall.

And now on ILK/SNB/IVB/HSW the irq_preinstall and irq_postinstall
functions leave the hardware in the same state.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/i915_irq.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 461c9a5..dd8e8b6 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -2684,6 +2684,8 @@ static void ironlake_irq_reset(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
+	I915_WRITE(HWSTAM, 0xffffffff);
+
 	GEN5_IRQ_RESET(DE);
 	if (IS_GEN7(dev))
 		I915_WRITE(GEN7_ERR_INT, 0xffffffff);
@@ -2695,10 +2697,6 @@ static void ironlake_irq_reset(struct drm_device *dev)
 
 static void ironlake_irq_preinstall(struct drm_device *dev)
 {
-	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-
-	I915_WRITE(HWSTAM, 0xeffe);
-
 	ironlake_irq_reset(dev);
 }
 
@@ -2881,6 +2879,8 @@ static int ironlake_irq_postinstall(struct drm_device *dev)
 
 	dev_priv->irq_mask = ~display_mask;
 
+	I915_WRITE(HWSTAM, 0xeffe);
+
 	ibx_irq_pre_postinstall(dev);
 
 	GEN5_IRQ_INIT(DE, dev_priv->irq_mask, display_mask | extra_mask);
@@ -3063,8 +3063,6 @@ static void ironlake_irq_uninstall(struct drm_device *dev)
 
 	intel_hpd_irq_uninstall(dev_priv);
 
-	I915_WRITE(HWSTAM, 0xffffffff);
-
 	ironlake_irq_reset(dev);
 }
 
-- 
1.8.4.2