diff mbox series

[2/2] drm/i915: Implement Wa_1607090982

Message ID 20200207155138.30978-2-mika.kuoppala@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series [1/2] drm/i915: Disable tesselation clock gating on tgl A0 | expand

Commit Message

Mika Kuoppala Feb. 7, 2020, 3:51 p.m. UTC
SIMD16 with Src0 scalar might conflict between Src1/Src2 and cause
GRF read issue. Workaround this issue by setting bit 14 in 0xe4f4
which will disable early read/src swap of Src0.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
---
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 3 +++
 drivers/gpu/drm/i915/i915_reg.h             | 2 ++
 2 files changed, 5 insertions(+)

Comments

Chris Wilson Feb. 7, 2020, 3:59 p.m. UTC | #1
Quoting Mika Kuoppala (2020-02-07 15:51:38)
> SIMD16 with Src0 scalar might conflict between Src1/Src2 and cause
> GRF read issue. Workaround this issue by setting bit 14 in 0xe4f4
> which will disable early read/src swap of Src0.
> 
> Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Found!
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 4bbea781c142..62b43f538a56 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -598,6 +598,9 @@  static void tgl_ctx_workarounds_init(struct intel_engine_cs *engine,
 	wa_add(wal, FF_MODE2, FF_MODE2_TDS_TIMER_MASK, val,
 	       IS_TGL_REVID(engine->i915, TGL_REVID_A0, TGL_REVID_A0) ? 0 :
 			    FF_MODE2_TDS_TIMER_MASK);
+
+	/* Wa_1606931601:tgl */
+	WA_SET_BIT_MASKED(GEN7_ROW_CHICKEN2, GEN12_DISABLE_EARLY_READ);
 }
 
 static void
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index b62029a10ed6..590eff9f03d5 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -9148,6 +9148,8 @@  enum {
 #define   DISABLE_EARLY_EOT			(1 << 1)
 
 #define GEN7_ROW_CHICKEN2		_MMIO(0xe4f4)
+#define GEN12_DISABLE_EARLY_READ	BIT(14)
+
 #define GEN7_ROW_CHICKEN2_GT2		_MMIO(0xf4f4)
 #define   DOP_CLOCK_GATING_DISABLE	(1 << 0)
 #define   PUSH_CONSTANT_DEREF_DISABLE	(1 << 8)