drm/i915/gen11: fix the SAGV block time for gen11

It's 10us for gen 11.
Reviewed-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Reviewed-by: James Ausmus <james.ausmus@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180130134918.32283-7-paulo.r.zanoni@intel.com

drivers/gpu/drm/i915/intel_pm.c

@@ -3694,11 +3694,18 @@ bool intel_can_enable_sagv(struct drm_atomic_state *state)
 	struct intel_crtc_state *cstate;
 	enum pipe pipe;
 	int level, latency;
-	int sagv_block_time_us = IS_GEN9(dev_priv) ? 30 : 20;
+	int sagv_block_time_us;
 
 	if (!intel_has_sagv(dev_priv))
 		return false;
 
+	if (IS_GEN9(dev_priv))
+		sagv_block_time_us = 30;
+	else if (IS_GEN10(dev_priv))
+		sagv_block_time_us = 20;
+	else
+		sagv_block_time_us = 10;
+
 	/*
 	 * SKL+ workaround: bspec recommends we disable the SAGV when we have
 	 * more then one pipe enabled