[Intel-gfx] [PATCH 3/3] drm/i915: disable MSI on Ironlake temporarily

[Zhenyu Wang]

We've seen interrupt stall issue in compiz testing, which disappears
with MSI disabled. Until we figure out why it's broken, disable it now.

Signed-off-by: Zhenyu Wang <zhenyuw at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_dma.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index bc679ff..58f7bda 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1460,8 +1460,11 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	 * According to chipset errata, on the 965GM, MSI interrupts may
 	 * be lost or delayed, but we use them anyways to avoid
 	 * stuck interrupts on some machines.
+	 *
+	 * MSI looks unstable on Ironlake, until we find out the reason, disable
+	 * it for now.
 	 */
-	if (!IS_I945G(dev) && !IS_I945GM(dev))
+	if (!IS_I945G(dev) && !IS_I945GM(dev) && !IS_IGDNG(dev))
 		pci_enable_msi(dev->pdev);
 
 	spin_lock_init(&dev_priv->user_irq_lock);
-- 
1.6.3.3