[PATCH 4/4] drm/i915: Try removing the forcewake get/put around the fifo counting.

[Eric Anholt <eric@anholt.net>]

This reintroduces the IRQ misses, with 2 events in 1874 runs.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/i915/i915_drv.c |   16 +++++++++++-----
 1 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index eabf82c..5444032 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -383,18 +383,24 @@ void __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
 void
 intel_posting_read(struct drm_i915_private *dev_priv, uint32_t reg)
 {
-	int ret;
+	u32 fifo;
+	int loop = 5000;
 
 	if (dev_priv->info->gen < 6) {
 		(void)I915_READ_NOTRACE(reg);
 		return;
 	}
 
-	gen6_gt_force_wake_get(dev_priv);
-	ret = wait_for(I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES) == 0x3f, 500);
-	gen6_gt_force_wake_put(dev_priv);
+	if (!I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES))
+		printk("it got 0\n");
+
+	fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
+	while (fifo != 0x3f && --loop) {
+		udelay(10);
+		fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
+	}
 
-	WARN_ON_ONCE(ret != 0);
+	WARN_ON_ONCE(loop == 0);
 }
 
 static int i915_drm_freeze(struct drm_device *dev)
-- 
1.7.5.1