drm/i915/tgl: Introduce initial Tiger Lake workarounds

Add empty workaround hooks for Tiger Lake. The workarounds will be added
on separate patches. We were already applying
WaRsForcewakeAddDelayForAck, which is indeed still valid, so also update
the comment.

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190817093902.2171-21-lucas.demarchi@intel.com

drivers/gpu/drm/i915/gt/intel_lrc.c

@@ -2225,6 +2225,7 @@ static int intel_init_workaround_bb(struct intel_engine_cs *engine)
 		return 0;
 
 	switch (INTEL_GEN(engine->i915)) {
+	case 12:
 	case 11:
 		return 0;
 	case 10:

drivers/gpu/drm/i915/gt/intel_workarounds.c

@@ -569,6 +569,11 @@ static void icl_ctx_workarounds_init(struct intel_engine_cs *engine,
 			  GEN11_SAMPLER_ENABLE_HEADLESS_MSG);
 }
 
+static void tgl_ctx_workarounds_init(struct intel_engine_cs *engine,
+				     struct i915_wa_list *wal)
+{
+}
+
 static void
 __intel_engine_init_ctx_wa(struct intel_engine_cs *engine,
 			   struct i915_wa_list *wal,
@@ -581,7 +586,9 @@ __intel_engine_init_ctx_wa(struct intel_engine_cs *engine,
 
 	wa_init_start(wal, name, engine->name);
 
-	if (IS_GEN(i915, 11))
+	if (IS_GEN(i915, 12))
+		tgl_ctx_workarounds_init(engine, wal);
+	else if (IS_GEN(i915, 11))
 		icl_ctx_workarounds_init(engine, wal);
 	else if (IS_CANNONLAKE(i915))
 		cnl_ctx_workarounds_init(engine, wal);
@@ -890,10 +897,17 @@ icl_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
 		    GAMT_CHKN_DISABLE_L3_COH_PIPE);
 }
 
+static void
+tgl_gt_workarounds_init(struct drm_i915_private *i915, struct i915_wa_list *wal)
+{
+}
+
 static void
 gt_init_workarounds(struct drm_i915_private *i915, struct i915_wa_list *wal)
 {
-	if (IS_GEN(i915, 11))
+	if (IS_GEN(i915, 12))
+		tgl_gt_workarounds_init(i915, wal);
+	else if (IS_GEN(i915, 11))
 		icl_gt_workarounds_init(i915, wal);
 	else if (IS_CANNONLAKE(i915))
 		cnl_gt_workarounds_init(i915, wal);
@@ -1183,6 +1197,10 @@ static void icl_whitelist_build(struct intel_engine_cs *engine)
 	}
 }
 
+static void tgl_whitelist_build(struct intel_engine_cs *engine)
+{
+}
+
 void intel_engine_init_whitelist(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *i915 = engine->i915;
@@ -1190,7 +1208,9 @@ void intel_engine_init_whitelist(struct intel_engine_cs *engine)
 
 	wa_init_start(w, "whitelist", engine->name);
 
-	if (IS_GEN(i915, 11))
+	if (IS_GEN(i915, 12))
+		tgl_whitelist_build(engine);
+	else if (IS_GEN(i915, 11))
 		icl_whitelist_build(engine);
 	else if (IS_CANNONLAKE(i915))
 		cnl_whitelist_build(engine);

drivers/gpu/drm/i915/intel_pm.c

@@ -9597,7 +9597,9 @@ static void nop_init_clock_gating(struct drm_i915_private *dev_priv)
  */
 void intel_init_clock_gating_hooks(struct drm_i915_private *dev_priv)
 {
-	if (IS_GEN(dev_priv, 11))
+	if (IS_GEN(dev_priv, 12))
+		dev_priv->display.init_clock_gating = nop_init_clock_gating;
+	else if (IS_GEN(dev_priv, 11))
 		dev_priv->display.init_clock_gating = icl_init_clock_gating;
 	else if (IS_CANNONLAKE(dev_priv))
 		dev_priv->display.init_clock_gating = cnl_init_clock_gating;