releases/4.8.17/drm-i915-initialize-dev_priv-atomic_cdclk_freq-at-init-time.patch

From 1f3dc3e334c1192ebe2939ea17ba12f4776f90c3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Tue, 29 Nov 2016 16:13:57 +0200
Subject: drm/i915: Initialize dev_priv->atomic_cdclk_freq at init time
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From: Ville Syrjälä <ville.syrjala@linux.intel.com>

commit 1f3dc3e334c1192ebe2939ea17ba12f4776f90c3 upstream.

Looks like we're only initializing dev_priv->atomic_cdclk_freq
at resume and commit times, not at init time. Let's do that as
well.

We're now hitting the 'WARN_ON(intel_state->cdclk == 0)' in
hsw_compute_linetime_wm() on account of populating
intel_state->cdclk from dev_priv->atomic_cdclk_freq.
Previously we were mispopulating intel_state->cdclk with
dev_priv->cdclk_freq which always had a proper value at init
time and hence the WARN_ON() didn't trigger.

Cc: Matthew Auld <matthew.auld@intel.com>
Reported-by: Matthew Auld <matthew.auld@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98902
Fixes: 14676ec6b1a6 ("drm/i915: Fix cdclk vs. dev_cdclk mess when not recomputing things")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480428837-4207-1-git-send-email-ville.syrjala@linux.intel.com
Tested-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
(cherry picked from commit 6a259b1f8a9e99b1ed114f8bf8b0cfccee130e54)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -15904,6 +15904,7 @@ void intel_modeset_init(struct drm_devic
 
 	intel_update_czclk(dev_priv);
 	intel_update_cdclk(dev);
+	dev_priv->atomic_cdclk_freq = dev_priv->cdclk_freq;
 
 	intel_shared_dpll_init(dev);