[Intel-gfx] [PATCH 6/8] drm/i915: change force wake order for GT read

[Zhenyu Wang]

Move FORCEWAKE_ACK == 0 wait after setting force wake to 0. This is
another way to set force wake for GT read from spec. And also this
makes RC6 setting order strictly follow spec.

Signed-off-by: Zhenyu Wang <zhenyuw at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c |   11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index dd8bd5c..a55b71d 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -264,10 +264,6 @@ void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
 {
 	int count;
 
-	count = 0;
-	while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_ACK) & 1))
-		udelay(10);
-
 	I915_WRITE_NOTRACE(FORCEWAKE, 1);
 	POSTING_READ(FORCEWAKE);
 
@@ -278,8 +274,15 @@ void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
 
 void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
 {
+	int count;
+
 	I915_WRITE_NOTRACE(FORCEWAKE, 0);
 	POSTING_READ(FORCEWAKE);
+
+	count = 0;
+	while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_ACK) & 1))
+		udelay(10);
+
 }
 
 void __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
-- 
1.7.4.1