[Intel-gfx] [PATCH] drm/i915: Emit even number of dwords when emitting LRIs

[Arun Siluvery]

The number of DWords should be even when doing ring emits as
command sequences require QWord alignment.

v2: user LRI variant that can write multiple regs in one go (Damien).
We can simply insert one NOP at the end instead of one per register write.

Cc: Mika Kuoppala <mika.kuoppala at intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_ringbuffer.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 497b836..a8f72e8 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -680,15 +680,16 @@ static int intel_ring_workarounds_emit(struct intel_engine_cs *ring)
 	if (ret)
 		return ret;
 
-	ret = intel_ring_begin(ring, w->count * 3);
+	ret = intel_ring_begin(ring, (w->count * 2 + 2));
 	if (ret)
 		return ret;
 
+	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(w->count));
 	for (i = 0; i < w->count; i++) {
-		intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
 		intel_ring_emit(ring, w->reg[i].addr);
 		intel_ring_emit(ring, w->reg[i].value);
 	}
+	intel_ring_emit(ring, MI_NOOP);
 
 	intel_ring_advance(ring);
 
-- 
2.1.2