[Intel-gfx] [PATCH 3/4] drm/i915/gen9: Add WaFlushCoherentL3CacheLinesAtContextSwitch workaround

[Arun Siluvery]

In Indirect context w/a batch buffer,
+WaFlushCoherentL3CacheLinesAtContextSwitch:bdw

Cc: Imre Deak <imre.deak at intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery at linux.intel.com>
---

This patch depends on https://patchwork.kernel.org/patch/6715321/, which is
already reviewed by Chris, temporary dependency untill it gets merged.

 drivers/gpu/drm/i915/intel_lrc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 152b4f6..c4cac4d 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1282,6 +1282,11 @@ static int gen9_init_indirectctx_bb(struct intel_engine_cs *ring,
 	    (IS_BROXTON(dev) && (INTEL_REVID(dev) == SKL_REVID_A0)))
 		wa_ctx_emit(batch, MI_ARB_ON_OFF | MI_ARB_DISABLE);
 
+	/* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt */
+	index = gen8_emit_flush_coherentl3_wa(ring, batch, index);
+	if (index < 0)
+		return index;
+
 	/* Pad to end of cacheline */
 	while (index % CACHELINE_DWORDS)
 		wa_ctx_emit(batch, MI_NOOP);
-- 
1.9.1