From a69ab52b0358d630bfa31183a45903263b46eaf2 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 8 Aug 2018 11:51:01 +0100
Subject: [PATCH] drm/i915: Remove extra waiter kick on legacy resets
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Now with a more efficacious workaround for the lost interrupts after
reset, we can remove the hack of kicking the waiters after reset. The
issue was that the kick only worked for the immediate window after the
reset (those seqno that would complete in the time it took for the
waiter thread to perform its check) but miss any seqno that lacked an
interrupt afterwards.

References: 39f3be162c46 ("drm/i915: Kick waiters on resetting legacy rings")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180808105101.913-3-chris@chris-wilson.co.uk
---
 drivers/gpu/drm/i915/intel_ringbuffer.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index d40f55a8dc34..b65cf7832b39 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -537,8 +537,6 @@ static int init_ring_common(struct intel_engine_cs *engine)
 	if (INTEL_GEN(dev_priv) > 2)
 		I915_WRITE_MODE(engine, _MASKED_BIT_DISABLE(STOP_RING));
 
-	/* Papering over lost _interrupts_ immediately following the restart */
-	intel_engine_wakeup(engine);
 out:
 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
 
-- 
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