drm/i915/dg2: extend Wa_1409120013 to DG2

Extend existing workaround 1409120013 to DG2.

Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Matt Atwood <matthew.s.atwood@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211116174818.2128062-6-matthew.d.roper@intel.com

drivers/gpu/drm/i915/intel_pm.c

@@ -7452,9 +7452,9 @@ static void icl_init_clock_gating(struct drm_i915_private *dev_priv)
 
 static void gen12lp_init_clock_gating(struct drm_i915_private *dev_priv)
 {
-	/* Wa_1409120013:tgl,rkl,adl-s,dg1 */
+	/* Wa_1409120013:tgl,rkl,adl-s,dg1,dg2 */
 	if (IS_TIGERLAKE(dev_priv) || IS_ROCKETLAKE(dev_priv) ||
-	    IS_ALDERLAKE_S(dev_priv) || IS_DG1(dev_priv))
+	    IS_ALDERLAKE_S(dev_priv) || IS_DG1(dev_priv) || IS_DG2(dev_priv))
 		intel_uncore_write(&dev_priv->uncore, ILK_DPFC_CHICKEN,
 				   DPFC_CHICKEN_COMP_DUMMY_PIXEL);