[PATCH 3.8 03/14] drm/i915: fix DDI PLLs HW state readout code

[Kamal Mostafa]

3.8.13.17 -stable review patch.  If anyone has any objections, please let me know.

------------------

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

commit 0882dae983707455e97479e5e904e37673517ebc upstream.

Properly zero the refcounts and crtc->ddi_pll_set so the previous HW
state doesn't affect the result of reading the current HW state.

This fixes WARNs about WRPLL refcount if we have an HDMI monitor on
HSW and then suspend/resume.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64379
Tested-by: Qingshuai Tian <qingshuai.tian at intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/gpu/drm/i915/intel_ddi.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index b8e53d9..6f09de3 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1178,12 +1178,18 @@ void intel_ddi_setup_hw_pll_state(struct drm_device *dev)
 	enum pipe pipe;
 	struct intel_crtc *intel_crtc;
 
+	dev_priv->ddi_plls.spll_refcount = 0;
+	dev_priv->ddi_plls.wrpll1_refcount = 0;
+	dev_priv->ddi_plls.wrpll2_refcount = 0;
+
 	for_each_pipe(pipe) {
 		intel_crtc =
 			to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);
 
-		if (!intel_crtc->active)
+		if (!intel_crtc->active) {
+			intel_crtc->ddi_pll_sel = PORT_CLK_SEL_NONE;
 			continue;
+		}
 
 		intel_crtc->ddi_pll_sel = intel_ddi_get_crtc_pll(dev_priv,
 								 pipe);
-- 
1.8.3.2