drm/i915/mtl: Add Wa_14017856879

Wa_14017856879 implementation for mtl.

Bspec: 46046
Signed-off-by: Haridhar Kalvala <haridhar.kalvala@intel.com>
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404173220.3175577-1-haridhar.kalvala@intel.com

drivers/gpu/drm/i915/gt/intel_gt_regs.h

@@ -1179,7 +1179,9 @@
 #define   THREAD_EX_ARB_MODE_RR_AFTER_DEP	REG_FIELD_PREP(THREAD_EX_ARB_MODE, 0x2)
 
 #define HSW_ROW_CHICKEN3			_MMIO(0xe49c)
+#define GEN9_ROW_CHICKEN3			MCR_REG(0xe49c)
 #define   HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE	(1 << 6)
+#define   MTL_DISABLE_FIX_FOR_EOT_FLUSH		REG_BIT(9)
 
 #define GEN8_ROW_CHICKEN			MCR_REG(0xe4f0)
 #define   FLOW_CONTROL_ENABLE			REG_BIT(15)

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

@@ -3051,6 +3051,11 @@ general_render_compute_wa_init(struct intel_engine_cs *engine, struct i915_wa_li
 
 	add_render_compute_tuning_settings(i915, wal);
 
+	if (IS_MTL_GRAPHICS_STEP(i915, M, STEP_B0, STEP_FOREVER) ||
+	    IS_MTL_GRAPHICS_STEP(i915, P, STEP_B0, STEP_FOREVER))
+		/* Wa_14017856879 */
+		wa_mcr_masked_en(wal, GEN9_ROW_CHICKEN3, MTL_DISABLE_FIX_FOR_EOT_FLUSH);
+
 	if (IS_MTL_GRAPHICS_STEP(i915, M, STEP_A0, STEP_B0) ||
 	    IS_MTL_GRAPHICS_STEP(i915, P, STEP_A0, STEP_B0))
 		/*