[PATCH v4 4/5] drm/i915: Clarify flow for disabling IRQs on storms

From: Lyude Paul
Date: Mon Nov 05 2018 - 17:20:31 EST


This is rather confusing to look at as-is:
dev_priv->display.hpd_irq_setup(dev_priv); in intel_hpd_irq_handler()
handles disabling the actual HPD IRQ, while
intel_hpd_irq_storm_disable() handles moving the HPD pin state over from
MARK_DISABLED to DISABLED along with enabling polling for it.

Changes since v3:
- Rename i915_hpd_irq_storm_disable() to
i915_hpd_irq_storm_switch_to_polling() - Rodrigo Vivi

Cc: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
---
drivers/gpu/drm/i915/intel_hotplug.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c
index c11d73de16f2..d642c0795452 100644
--- a/drivers/gpu/drm/i915/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/intel_hotplug.c
@@ -161,7 +161,8 @@ static bool intel_hpd_irq_storm_detect(struct drm_i915_private *dev_priv,
return storm;
}

-static void intel_hpd_irq_storm_disable(struct drm_i915_private *dev_priv)
+static void
+intel_hpd_irq_storm_switch_to_polling(struct drm_i915_private *dev_priv)
{
struct drm_device *dev = &dev_priv->drm;
struct intel_connector *intel_connector;
@@ -351,8 +352,8 @@ static void i915_hotplug_work_func(struct work_struct *work)
hpd_event_bits = dev_priv->hotplug.event_bits;
dev_priv->hotplug.event_bits = 0;

- /* Disable hotplug on connectors that hit an irq storm. */
- intel_hpd_irq_storm_disable(dev_priv);
+ /* Enable polling for connectors which had HPD IRQ storms */
+ intel_hpd_irq_storm_switch_to_polling(dev_priv);

spin_unlock_irq(&dev_priv->irq_lock);

@@ -458,6 +459,10 @@ void intel_hpd_irq_handler(struct drm_i915_private *dev_priv,
}
}

+ /*
+ * Disable any IRQs that storms were detected on. Polling enablement
+ * happens later in our hotplug work.
+ */
if (storm_detected && dev_priv->display_irqs_enabled)
dev_priv->display.hpd_irq_setup(dev_priv);
spin_unlock(&dev_priv->irq_lock);
--
2.19.1