FAILED: patch "[PATCH] drm/i915: Disable SAMPLER_STATE prefetching on all Gen11" failed to apply to 5.2-stable tree

The patch below does not apply to the 5.2-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 248f883db61283b4f5a1c92a5e27277377b09f16 Mon Sep 17 00:00:00 2001
From: Kenneth Graunke <[email protected]>
Date: Tue, 25 Jun 2019 10:06:55 +0100
Subject: [PATCH] drm/i915: Disable SAMPLER_STATE prefetching on all Gen11
steppings.

The Demand Prefetch workaround (binding table prefetching) only applies to Icelake A0/B0. But the Sampler Prefetch workaround needs to be applied to all Gen11 steppings, according to a programming note in the SARCHKMD documentation.

Using the Intel Gallium driver, I have seen intermittent failures in the dEQP-GLES31.functional.copy_image.non_compressed.* tests. After applying this workaround, the tests reliably pass.

v2: Remove the overlap with a pre-production w/a

BSpec: 9663

index 15e90fd2cfdc..50c0060509a6 100644
@@ -1258,8 +1258,12 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
 		if (IS_ICL_REVID(i915, ICL_REVID_A0, ICL_REVID_B0))
 			wa_write_or(wal,
 				    GEN7_SARCHKMD,
-				    GEN7_DISABLE_DEMAND_PREFETCH |
-				    GEN7_DISABLE_SAMPLER_PREFETCH);
+				    GEN7_DISABLE_DEMAND_PREFETCH);
+
+		/* Wa_1606682166:icl */
+		wa_write_or(wal,
+			    GEN7_SARCHKMD,
+			    GEN7_DISABLE_SAMPLER_PREFETCH);
 	}
 
 	if (IS_GEN_RANGE(i915, 9, 11)) {