drm/i915/tgl: WaDisableGPGPUMidThreadPreemption

Enable FtrPerCtxtPreemptionGranularityControl bit and select thread-
group as the default preemption level.

v2:
 * Remove register whitelisting (Rafael, Tony).

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: piotr.zdunowski@intel.com
Cc: michal.mrozek@intel.com
Cc: Tony Ye <tony.ye@intel.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Acked-by: Rafael Antognolli <rafael.antognolli@intel.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Tony Ye <tony.ye@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304153144.10675-1-tvrtko.ursulin@linux.intel.com

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

@@ -601,6 +601,11 @@ static void tgl_ctx_workarounds_init(struct intel_engine_cs *engine,
 	 */
 	wa_add(wal, FF_MODE2, FF_MODE2_TDS_TIMER_MASK,
 	       FF_MODE2_TDS_TIMER_128, 0);
+
+	/* WaDisableGPGPUMidThreadPreemption:tgl */
+	WA_SET_FIELD_MASKED(GEN8_CS_CHICKEN1,
+			    GEN9_PREEMPT_GPGPU_LEVEL_MASK,
+			    GEN9_PREEMPT_GPGPU_THREAD_GROUP_LEVEL);
 }
 
 static void
@@ -1475,8 +1480,8 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
 			     PSDUNIT_CLKGATE_DIS);
 	}
 
-	if (IS_GEN_RANGE(i915, 9, 11)) {
-		/* FtrPerCtxtPreemptionGranularityControl:skl,bxt,kbl,cfl,cnl,icl */
+	if (IS_GEN_RANGE(i915, 9, 12)) {
+		/* FtrPerCtxtPreemptionGranularityControl:skl,bxt,kbl,cfl,cnl,icl,tgl */
 		wa_masked_en(wal,
 			     GEN7_FF_SLICE_CS_CHICKEN1,
 			     GEN9_FFSC_PERCTX_PREEMPT_CTRL);