From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 8 Aug 2018 10:51:01 +0000 (+0100)
Subject: drm/i915: Remove extra waiter kick on legacy resets
X-Git-Tag: v4.20-rc1~81^2~28^2~94
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a69ab52b0358;p=users%2Fdwmw2%2Flinux.git

drm/i915: Remove extra waiter kick on legacy resets

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
---

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index d40f55a8dc34a..b65cf7832b398 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);