drm/i915: catch forcewake reference underruns

Without this the new drv_suspend/forcewake subtest I've created
doesn't result in immediately visible failures.

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2014-03-15 20:20:29 +01:00
parent ae89f44d13
commit 3123fcafe0
1 changed files with 15 additions and 6 deletions

View File

@ -280,12 +280,17 @@ void vlv_force_wake_put(struct drm_i915_private *dev_priv,
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
if (fw_engine & FORCEWAKE_RENDER &&
--dev_priv->uncore.fw_rendercount != 0)
fw_engine &= ~FORCEWAKE_RENDER;
if (fw_engine & FORCEWAKE_MEDIA &&
--dev_priv->uncore.fw_mediacount != 0)
fw_engine &= ~FORCEWAKE_MEDIA;
if (fw_engine & FORCEWAKE_RENDER) {
WARN_ON(!dev_priv->uncore.fw_rendercount);
if (--dev_priv->uncore.fw_rendercount != 0)
fw_engine &= ~FORCEWAKE_RENDER;
}
if (fw_engine & FORCEWAKE_MEDIA) {
WARN_ON(!dev_priv->uncore.fw_mediacount);
if (--dev_priv->uncore.fw_mediacount != 0)
fw_engine &= ~FORCEWAKE_MEDIA;
}
if (fw_engine)
dev_priv->uncore.funcs.force_wake_put(dev_priv, fw_engine);
@ -301,6 +306,8 @@ static void gen6_force_wake_timer(unsigned long arg)
assert_device_not_suspended(dev_priv);
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
WARN_ON(!dev_priv->uncore.forcewake_count);
if (--dev_priv->uncore.forcewake_count == 0)
dev_priv->uncore.funcs.force_wake_put(dev_priv, FORCEWAKE_ALL);
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
@ -452,6 +459,8 @@ void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv, int fw_engine)
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
WARN_ON(!dev_priv->uncore.forcewake_count);
if (--dev_priv->uncore.forcewake_count == 0) {
dev_priv->uncore.forcewake_count++;
delayed = true;