Patch "drm/i915: Don't leave old junk in ilk active watermarks on readout" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

drm/i915: Don't leave old junk in ilk active watermarks on readout

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
drm-i915-don-t-leave-old-junk-in-ilk-active-watermarks-on-readout.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <[email protected]>
Date: Fri, 13 May 2016 17:55:17 +0300
Subject: drm/i915: Don't leave old junk in ilk active watermarks on readout
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From: Ville Syrjälä <[email protected]>

commit 7045c3689f148a0c95f42bae8ef3eb2829ac7de9 upstream.

When we read out the watermark state from the hardware we're supposed to transfer that into the active watermarks, but currently we fail to any part of the active watermarks that isn't explicitly written. Let's clear it all upfront.

Looks like this has been like this since the beginning, when I added the readout. No idea why I didn't clear it up.

---
 drivers/gpu/drm/i915/intel_pm.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -3880,6 +3880,8 @@ static void ilk_pipe_wm_get_hw_state(str
 	if (IS_HASWELL(dev) || IS_BROADWELL(dev))
 		hw->wm_linetime[pipe] = I915_READ(PIPE_WM_LINETIME(pipe));
 
+	memset(active, 0, sizeof(*active));
+
 	active->pipe_enabled = intel_crtc->active;
 
 	if (active->pipe_enabled) {

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/mfd-intel_soc_pmic_core-terminate-panel-control-gpio-lookup-table-correctly.patch queue-4.4/drm-i915-don-t-leave-old-junk-in-ilk-active-watermarks-on-readout.patch