drm/i915: Enable display WA#1183 from its correct spot

commit ac315c6 upstream.

The DMC FW specific part of display WA#1183 is supposed to be enabled
whenever enabling DC5 or DC6, so move it to the DC6 enable function
from the DC6 disable function.

I noticed this after Daniel's patch to remove the unused
skl_disable_dc6() function.

Fixes: 53421c2 ("drm/i915: Apply Display WA #1183 on skl, kbl, and cfl")
Cc: Lucas De Marchi <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: <[email protected]>
Signed-off-by: Imre Deak <[email protected]>
Reviewed-by: Ville Syrjälä <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit b49be66)
Signed-off-by: Joonas Lahtinen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: ideak

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -624,19 +624,18 @@ void skl_enable_dc6(struct drm_i915_private *dev_priv)
 
 	DRM_DEBUG_KMS("Enabling DC6\n");
 
-	gen9_set_dc_state(dev_priv, DC_STATE_EN_UPTO_DC6);
+	/* Wa Display #1183: skl,kbl,cfl */
+	if (IS_GEN9_BC(dev_priv))
+		I915_WRITE(GEN8_CHICKEN_DCPR_1, I915_READ(GEN8_CHICKEN_DCPR_1) |
+			   SKL_SELECT_ALTERNATE_DC_EXIT);
 
+	gen9_set_dc_state(dev_priv, DC_STATE_EN_UPTO_DC6);
 }
 
 void skl_disable_dc6(struct drm_i915_private *dev_priv)
 {
 	DRM_DEBUG_KMS("Disabling DC6\n");
 
-	/* Wa Display #1183: skl,kbl,cfl */
-	if (IS_GEN9_BC(dev_priv))
-		I915_WRITE(GEN8_CHICKEN_DCPR_1, I915_READ(GEN8_CHICKEN_DCPR_1) |
-			   SKL_SELECT_ALTERNATE_DC_EXIT);
-
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 }