[Intel-gfx] [PATCH 07/27] drm/i915/kbl: Add WaEnableGapsTsvCreditFix

[Mika Kuoppala]

We need this crucial workaround from skl also to all kbl revisions.
Lack of it was causing system hangs on skl enabling so this is
a must have.

v2: Don't add revid checks to gen9 init workarounds (Arun)

References: HSD#2126660
Cc: Arun Siluvery <arun.siluvery at linux.intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala at intel.com>
Reviewed-by: Matthew Auld <matthew.auld at intel.com>
---
 drivers/gpu/drm/i915/intel_ringbuffer.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 228c3f75d3c5..02edf85f7456 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1188,12 +1188,17 @@ static int bxt_init_workarounds(struct intel_engine_cs *engine)
 
 static int kbl_init_workarounds(struct intel_engine_cs *engine)
 {
+	struct drm_i915_private *dev_priv = engine->i915;
 	int ret;
 
 	ret = gen9_init_workarounds(engine);
 	if (ret)
 		return ret;
 
+	/* WaEnableGapsTsvCreditFix:kbl */
+	I915_WRITE(GEN8_GARBCNTL, (I915_READ(GEN8_GARBCNTL) |
+				   GEN9_GAPS_TSV_CREDIT_DISABLE));
+
 	return 0;
 }
 
-- 
2.7.4