drm/i915: Move GT powersaving init to i915_gem_init()

GT powersaving is tightly coupled to the request infrastructure. To
avoid complications with the order of initialisation in the next patch
(where we want to send requests to hw during GEM init) move the
powersaving initialisation into the purview of i915_gem_init().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171110142634.10551-3-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem.c

@@ -5021,6 +5021,8 @@ int i915_gem_init(struct drm_i915_private *dev_priv)
 	if (ret)
 		goto out_unlock;
 
+	intel_init_gt_powersave(dev_priv);
+
 	ret = i915_gem_init_hw(dev_priv);
 	if (ret == -EIO) {
 		/* Allow engine initialisation to fail by marking the GPU as

drivers/gpu/drm/i915/intel_display.c

@@ -15198,8 +15198,6 @@ void intel_modeset_gem_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = to_i915(dev);
 
-	intel_init_gt_powersave(dev_priv);
-
 	intel_init_clock_gating(dev_priv);
 
 	intel_setup_overlay(dev_priv);

drivers/gpu/drm/i915/intel_pm.c

@@ -7918,7 +7918,6 @@ void intel_init_gt_powersave(struct drm_i915_private *dev_priv)
 		intel_runtime_pm_get(dev_priv);
 	}
 
-	mutex_lock(&dev_priv->drm.struct_mutex);
 	mutex_lock(&dev_priv->pcu_lock);
 
 	/* Initialize RPS limits (for userspace) */
@@ -7960,7 +7959,6 @@ void intel_init_gt_powersave(struct drm_i915_private *dev_priv)
 	rps->boost_freq = rps->max_freq;
 
 	mutex_unlock(&dev_priv->pcu_lock);
-	mutex_unlock(&dev_priv->drm.struct_mutex);
 
 	intel_autoenable_gt_powersave(dev_priv);
 }