From: Kenneth Graunke Date: Tue, 25 Jun 2019 09:06:55 +0000 (+0100) Subject: drm/i915: Disable SAMPLER_STATE prefetching on all Gen11 steppings. X-Git-Tag: v5.4-rc1~106^2~19^2~316 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=f9a393875d3af13cc3267477746608dadb7f17c1;p=linux.git 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 Signed-off-by: Kenneth Graunke Signed-off-by: Chris Wilson Cc: stable@vger.kernel.org Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20190625090655.19220-1-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c index 2835ab70199b..d776e111e5d0 100644 --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c @@ -1252,8 +1252,12 @@ 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)) {