blob: 76c937e9025c59766439e180d5e89693fd4cce67 [file] [log] [blame]
From cc8ca4b073223cc758d437dd8026a1e7cddd4d6e Mon Sep 17 00:00:00 2001
From: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date: Thu, 19 Sep 2013 17:00:36 -0300
Subject: drm/i915: don't disable ERR_INT on the IRQ handler
We currently disable the ERR_INT interrupts while running the IRQ
handler because we fear that if we do an unclaimed register access
from inside the IRQ handler we'll keep triggering the IRQ handler
forever.
The problem is that since we always disable the ERR_INT interrupts at
the IRQ handler, when we get a FIFO underrun we'll always print both
messages:
- "uncleared fifo underrun on pipe A"
- "Pipe A FIFO underrun"
Because the "was_enabled" variable from
ivybridge_set_fifo_underrun_reporting will always be false (since we
disable ERR int at the IRQ handler!).
Instead of actually fixing ivybridge_set_fifo_underrun_reporting,
let's just remove the "disable ERR_INT during the IRQ handler" code.
As far as we know we shouldn't really be triggering ERR_INT interrupts
from the IRQ handler, so if we ever get stuck in the endless loop of
interrupts we can git-bisect and revert (and we can even bisect and
revert this patch in case I'm just wrong). As a bonus, our IRQ handler
is now simpler and a few nanoseconds faster.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 6ceeeec04509ac40f91cfc8ffc129e22a136aafe)
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
drivers/gpu/drm/i915/i915_irq.c | 19 -------------------
1 file changed, 19 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index cfaf434010ae..b356dc15adda 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1421,7 +1421,6 @@ static irqreturn_t ironlake_irq_handler(int irq, void *arg)
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
u32 de_iir, gt_iir, de_ier, sde_ier = 0;
irqreturn_t ret = IRQ_NONE;
- bool err_int_reenable = false;
atomic_inc(&dev_priv->irq_received);
@@ -1445,17 +1444,6 @@ static irqreturn_t ironlake_irq_handler(int irq, void *arg)
POSTING_READ(SDEIER);
}
- /* On Haswell, also mask ERR_INT because we don't want to risk
- * generating "unclaimed register" interrupts from inside the interrupt
- * handler. */
- if (IS_HASWELL(dev)) {
- spin_lock(&dev_priv->irq_lock);
- err_int_reenable = ~dev_priv->irq_mask & DE_ERR_INT_IVB;
- if (err_int_reenable)
- ironlake_disable_display_irq(dev_priv, DE_ERR_INT_IVB);
- spin_unlock(&dev_priv->irq_lock);
- }
-
gt_iir = I915_READ(GTIIR);
if (gt_iir) {
if (INTEL_INFO(dev)->gen >= 6)
@@ -1485,13 +1473,6 @@ static irqreturn_t ironlake_irq_handler(int irq, void *arg)
}
}
- if (err_int_reenable) {
- spin_lock(&dev_priv->irq_lock);
- if (ivb_can_enable_err_int(dev))
- ironlake_enable_display_irq(dev_priv, DE_ERR_INT_IVB);
- spin_unlock(&dev_priv->irq_lock);
- }
-
I915_WRITE(DEIER, de_ier);
POSTING_READ(DEIER);
if (!HAS_PCH_NOP(dev)) {
--
1.8.5.rc3