From f63078abff0d2927c2f58f22b1082520def70865 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Winiarski?= <michal.winiarski@intel.com>
Date: Tue, 23 May 2017 12:23:59 +0200
Subject: [PATCH] drm/i915/guc: Skip port assign on first iteration of GuC
dequeue
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If port[0] is occupied and we're trying to dequeue request from
different context, we will inevitably hit BUG_ON in port_assign.
Let's skip it - similar to what we're doing in execlists counterpart.
Fixes: 77f0d0e925e8a0 ("drm/i915/execlists: Pack the count into the low bits of the port.request")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Wajdeczko <michal.wajdeczko@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170523102400.9614-2-michal.winiarski@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/i915_guc_submission.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 777f48e9bb33b..e6e0c6ef1084b 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -681,7 +681,8 @@ static bool i915_guc_dequeue(struct intel_engine_cs *engine)
goto done;
}
- port_assign(port, last);
+ if (submit)
+ port_assign(port, last);
port++;
}