Patch "drm/i915: Update watermark state correctly in sanitize_watermarks" has been added to the 4.14-stable tree

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

drm/i915: Update watermark state correctly in sanitize_watermarks

to the 4.14-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-update-watermark-state-correctly-in-sanitize_watermarks.patch
and it can be found in the queue-4.14 subdirectory.

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

From: Maarten Lankhorst <[email protected]>
Date: Fri, 10 Nov 2017 12:34:53 +0100
Subject: drm/i915: Update watermark state correctly in sanitize_watermarks
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From: Maarten Lankhorst <[email protected]>

commit 556fe36d09da5f82879e92bafa0371b4b79f7d6f upstream.

We no longer use intel_crtc->wm.active for watermarks any more, which was incorrect. But this uncovered a bug in sanitize_watermarks(), which meant that we wrote the correct watermarks, but the next update would still use the wrong hw watermarks for calculating. This caused all further updates to fail with -EINVAL and the log would reveal an error like the one below:

[   10.043902] [drm:ilk_validate_wm_level.part.8 [i915]] Sprite WM0 too large 56 (max 0)
[   10.043960] [drm:ilk_validate_pipe_wm [i915]] LP0 watermark invalid
[   10.044030] [drm:intel_crtc_atomic_check [i915]] No valid intermediate pipe watermarks are possible

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

@@ -14498,6 +14498,8 @@ retry:
 
 		cs->wm.need_postvbl_update = true;
 		dev_priv->display.optimize_watermarks(intel_state, cs);
+
+		to_intel_crtc_state(crtc->state)->wm = cs->wm;
 	}
 
 put_state:

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

queue-4.14/drm-i915-update-watermark-state-correctly-in-sanitize_watermarks.patch queue-4.14/drm-i915-always-call-to-intel_display_set_init_power-in-resume_early.patch