drm/i915: Fix init_clock_gating for resume

commit 3572f04c69ed4369da5d3c65d84fb18774aa60b6 upstream.

Moving the init_clock_gating() call from intel_modeset_init_hw() to
intel_modeset_gem_init() had an unintended effect of not applying
some workarounds on resume. This, for example, cause some kind of
corruption to appear at the top of my IVB Thinkpad X1 Carbon LVDS
screen after hibernation. Fix the problem by explicitly calling
init_clock_gating() from the resume path.

I really hope this doesn't break something else again. At least
the problems reported at https://bugs.freedesktop.org/show_bug.cgi?id=103549
didn't make a comeback, even after a hibernate cycle.

v2: Reorder the init_clock_gating vs. modeset_init_hw to match
    the display reset path (Rodrigo)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Fixes: 6ac43272768c ("drm/i915: Move init_clock_gating() back to where it was")
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171116160215.25715-1-ville.syrjala@linux.intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit 675f7ff35bd256e65d3d0f52718d8babf5d1002a)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 82498f8232eb042e789aa7339fec5b104ab1ebbe..5c5cb2ceee49aee3b7e65fb4eb00d9929e60881c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1693,6 +1693,7 @@ static int i915_drm_resume(struct drm_device *dev)
        intel_guc_resume(dev_priv);
 
        intel_modeset_init_hw(dev);
+       intel_init_clock_gating(dev_priv);
 
        spin_lock_irq(&dev_priv->irq_lock);
        if (dev_priv->display.hpd_irq_setup)