drm/i915: Delay the release of the forcewake by a jiffie

[~andy/linux] / drivers / gpu / drm / i915 / intel_uncore.c

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index 8649f1c36b007f89ea5b2bbf8bf3bb26090d9f52..f2753d9fb0989e3eec6eb51ecf948af8f18932fe 100644 (file)
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -204,6 +204,18 @@ static void vlv_force_wake_put(struct drm_i915_private *dev_priv)
        gen6_gt_check_fifodbg(dev_priv);
 }
 
+static void gen6_force_wake_work(struct work_struct *work)
+{
+       struct drm_i915_private *dev_priv =
+               container_of(work, typeof(*dev_priv), uncore.force_wake_work.work);
+       unsigned long irqflags;
+
+       spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+       if (--dev_priv->uncore.forcewake_count == 0)
+               dev_priv->uncore.funcs.force_wake_put(dev_priv);
+       spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
+}
+
 void intel_uncore_early_sanitize(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
@@ -216,6 +228,9 @@ void intel_uncore_init(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
 
+       INIT_DELAYED_WORK(&dev_priv->uncore.force_wake_work,
+                         gen6_force_wake_work);
+
        if (IS_VALLEYVIEW(dev)) {
                dev_priv->uncore.funcs.force_wake_get = vlv_force_wake_get;
                dev_priv->uncore.funcs.force_wake_put = vlv_force_wake_put;
@@ -261,6 +276,16 @@ void intel_uncore_init(struct drm_device *dev)
        }
 }
 
+void intel_uncore_fini(struct drm_device *dev)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+
+       flush_delayed_work(&dev_priv->uncore.force_wake_work);
+
+       /* Paranoia: make sure we have disabled everything before we exit. */
+       intel_uncore_sanitize(dev);
+}
+
 static void intel_uncore_forcewake_reset(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
@@ -306,8 +331,12 @@ void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
        unsigned long irqflags;
 
        spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
-       if (--dev_priv->uncore.forcewake_count == 0)
-               dev_priv->uncore.funcs.force_wake_put(dev_priv);
+       if (--dev_priv->uncore.forcewake_count == 0) {
+               dev_priv->uncore.forcewake_count++;
+               mod_delayed_work(dev_priv->wq,
+                                &dev_priv->uncore.force_wake_work,
+                                1);
+       }
        spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }