drm/i915/bxt: Enable DC5 during runtime resume

Right after runtime resume we know that we can re-enable DC5, since we
just disabled DC9 and power well 2 is disabled. So enable DC5 explicitly
instead of delaying this until the next time we disable power well 2.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461173277-16090-5-git-send-email-imre.deak@intel.com

drivers/gpu/drm/i915/i915_drv.c

@@ -1601,6 +1601,9 @@ static int intel_runtime_resume(struct device *device)
 	if (IS_BROXTON(dev)) {
 		bxt_disable_dc9(dev_priv);
 		bxt_display_core_init(dev_priv, true);
+		if (dev_priv->csr.dmc_payload &&
+		    (dev_priv->csr.allowed_dc_mask & DC_STATE_EN_UPTO_DC5))
+			gen9_enable_dc5(dev_priv);
 	} else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
 		hsw_disable_pc8(dev_priv);
 	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {

drivers/gpu/drm/i915/intel_drv.h

@@ -1238,6 +1238,7 @@ void broxton_ddi_phy_verify_state(struct drm_i915_private *dev_priv);
 void gen9_sanitize_dc_state(struct drm_i915_private *dev_priv);
 void bxt_enable_dc9(struct drm_i915_private *dev_priv);
 void bxt_disable_dc9(struct drm_i915_private *dev_priv);
+void gen9_enable_dc5(struct drm_i915_private *dev_priv);
 void skl_init_cdclk(struct drm_i915_private *dev_priv);
 int skl_sanitize_cdclk(struct drm_i915_private *dev_priv);
 void skl_uninit_cdclk(struct drm_i915_private *dev_priv);

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -582,7 +582,7 @@ static void assert_can_enable_dc5(struct drm_i915_private *dev_priv)
 	assert_csr_loaded(dev_priv);
 }
 
-static void gen9_enable_dc5(struct drm_i915_private *dev_priv)
+void gen9_enable_dc5(struct drm_i915_private *dev_priv)
 {
 	assert_can_enable_dc5(dev_priv);