drm/i915: Mark up early pre-production Kabylakes

Mark A0 as the one and only pre-production variant of Kabylake and
remove its couple of workarounds, consigning them to the annals of
history.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128135325.10641-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_drv.c

@@ -868,6 +868,7 @@ static void intel_detect_preproduction_hw(struct drm_i915_private *dev_priv)
 	pre |= IS_HSW_EARLY_SDV(dev_priv);
 	pre |= IS_SKL_REVID(dev_priv, 0, SKL_REVID_F0);
 	pre |= IS_BXT_REVID(dev_priv, 0, BXT_REVID_B_LAST);
+	pre |= IS_KBL_REVID(dev_priv, 0, KBL_REVID_A0);
 
 	if (pre) {
 		DRM_ERROR("This is a pre-production stepping. "

drivers/gpu/drm/i915/intel_lrc.c

@@ -1401,18 +1401,6 @@ static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
 
 	batch = emit_lri(batch, lri, ARRAY_SIZE(lri));
 
-	/* WaClearSlmSpaceAtContextSwitch:kbl */
-	/* Actual scratch location is at 128 bytes offset */
-	if (IS_KBL_REVID(engine->i915, 0, KBL_REVID_A0)) {
-		batch = gen8_emit_pipe_control(batch,
-					       PIPE_CONTROL_FLUSH_L3 |
-					       PIPE_CONTROL_GLOBAL_GTT_IVB |
-					       PIPE_CONTROL_CS_STALL |
-					       PIPE_CONTROL_QW_WRITE,
-					       i915_ggtt_offset(engine->scratch)
-					       + 2 * CACHELINE_BYTES);
-	}
-
 	/* WaMediaPoolStateCmdInWABB:bxt,glk */
 	if (HAS_POOLED_EU(engine->i915)) {
 		/*

drivers/gpu/drm/i915/intel_workarounds.c

@@ -384,11 +384,6 @@ static int kbl_ctx_workarounds_init(struct drm_i915_private *dev_priv)
 	if (ret)
 		return ret;
 
-	/* WaDisableFenceDestinationToSLM:kbl (pre-prod) */
-	if (IS_KBL_REVID(dev_priv, KBL_REVID_A0, KBL_REVID_A0))
-		WA_SET_BIT_MASKED(HDC_CHICKEN0,
-				  HDC_FENCE_DEST_SLM_DISABLE);
-
 	/* WaToEnableHwFixForPushConstHWBug:kbl */
 	if (IS_KBL_REVID(dev_priv, KBL_REVID_C0, REVID_FOREVER))
 		WA_SET_BIT_MASKED(COMMON_SLICE_CHICKEN2,