Starting with Xe_LP+, GFX_MSTR_IRQ contains status bits that have W1C
behavior. If we do not properly reset them, we would miss delivery of
interrupts if a pending bit is set when enabling IRQs.
As an example, the display part of our probe routine contains paths
where we wait for vblank interrupts. If a display interrupt was already
pending when enabling IRQs, we would time out waiting for the vblank.
Avoid the potential issue by clearing GFX_MSTR_IRQ as part of the IRQ
reset.
v2:
- Move logic from gen11_gt_irq_reset() to dg1_irq_reset(). (Matt)
BSpec: 50875, 54028
Cc: Matt Roper <matthew.d.ro...@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.so...@intel.com>
---
drivers/gpu/drm/i915/i915_irq.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 1bfcfbe6e30b..8130f043693b 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -751,6 +751,8 @@ static void dg1_irq_reset(struct drm_i915_private *dev_priv)
GEN3_IRQ_RESET(uncore, GEN11_GU_MISC_);
GEN3_IRQ_RESET(uncore, GEN8_PCU_);
+
+ intel_uncore_write(uncore, GEN11_GFX_MSTR_IRQ, ~0);
}
static void cherryview_irq_reset(struct drm_i915_private *dev_priv)
--
2.42.0
