From 7292b9e6586534fb43e4316ad8b508bf3d1212f7 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 12 Feb 2018 09:39:28 +0000
Subject: [PATCH] drm/i915: Don't wake the device up to check if the engine is asleep
Git-commit: 7292b9e6586534fb43e4316ad8b508bf3d1212f7
Patch-mainline: v4.16-rc2
No-fix: 74d00d28a15c8452f65de0a9477b52d95639cc63
References: FATE#322643 bsc#1055900
If the entire device is powered off, we can safely assume that the
engine is also asleep (and idle).
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: a091d4ee931b ("drm/i915: Hold a wakeref for probing the ring registers")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180212093928.6005-1-chris@chris-wilson.co.uk
(cherry picked from commit 74d00d28a15c8452f65de0a9477b52d95639cc63)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_engine_cs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1458,7 +1458,9 @@ static bool ring_is_idle(struct intel_en
struct drm_i915_private *dev_priv = engine->i915;
bool idle = true;
- intel_runtime_pm_get(dev_priv);
+ /* If the whole device is asleep, the engine must be idle */
+ if (!intel_runtime_pm_get_if_in_use(dev_priv))
+ return true;
/* First check that no commands are left in the ring */
if ((I915_READ_HEAD(engine) & HEAD_ADDR) !=