[Intel-gfx] [PATCH 4/6] drm/i915: set ILK_DPFC_FENCE_YOFF to 0 on SNB

[Paulo Zanoni]

From: Paulo Zanoni <paulo.r.zanoni at intel.com>

The doc is pretty clear that this register should be set to 0 on SNB.
We already write y_offset to DPFC_CPU_FENCE_OFFSET a few lines below.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
 drivers/gpu/drm/i915/intel_fbc.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c
index 0373cbc..0a24e96 100644
--- a/drivers/gpu/drm/i915/intel_fbc.c
+++ b/drivers/gpu/drm/i915/intel_fbc.c
@@ -216,7 +216,12 @@ static void ilk_fbc_enable(struct intel_crtc *crtc)
 		dpfc_ctl |= obj->fence_reg;
 
 	y_offset = get_crtc_fence_y_offset(crtc);
-	I915_WRITE(ILK_DPFC_FENCE_YOFF, y_offset);
+
+	if (IS_GEN5(dev_priv))
+		I915_WRITE(ILK_DPFC_FENCE_YOFF, y_offset);
+	else
+		I915_WRITE(ILK_DPFC_FENCE_YOFF, 0);
+
 	I915_WRITE(ILK_FBC_RT_BASE, i915_gem_obj_ggtt_offset(obj) | ILK_FBC_RT_VALID);
 	/* enable it... */
 	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
-- 
2.1.4