Revert "drm/i915: Avoid using PIPE_CONTROL on Ironlake"
Restore PIPE_CONTROL once again just for Ironlake, as it appears that
MI_USER_INTERRUPT does not have the same coherency guarantees, that is
on Ironlake the interrupt following a GPU write is not guaranteed to
arrive after the write is coherent from the CPU, as it does on the
other generations.
Reported-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Reported-by: Shuang He <shuang.he@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=32402
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 2ddb98b..e4a2e2c 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -349,7 +349,7 @@
READ_BREADCRUMB(dev_priv);
}
- if (gt_iir & GT_USER_INTERRUPT)
+ if (gt_iir & (GT_USER_INTERRUPT | GT_PIPE_NOTIFY))
notify_ring(dev, &dev_priv->ring[RCS]);
if (gt_iir & bsd_usr_interrupt)
notify_ring(dev, &dev_priv->ring[VCS]);
@@ -1558,6 +1558,7 @@
else
render_irqs =
GT_USER_INTERRUPT |
+ GT_PIPE_NOTIFY |
GT_BSD_USER_INTERRUPT;
I915_WRITE(GTIER, render_irqs);
POSTING_READ(GTIER);