From 70e39b4f93bd6e4901ab13c1fcc405a6212c248a Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 17 Jan 2020 18:03:09 +0000
Subject: drm/i915/gt: Be paranoid and reset the GPU before release
Git-commit: cd69952778aa4fc9325d993eea52dfff796f8e22
Patch-mainline: v5.7-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Just in the very unlikely case we have not stopped the GPU before we
return the pages being used by the GPU to the system, force a reset.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200117180309.3249427-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 2d0ef5fc6748..b4b69a3fa25c 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -35,6 +35,7 @@
#include "intel_engine_user.h"
#include "intel_gt.h"
#include "intel_gt_requests.h"
+#include "intel_gt_pm.h"
#include "intel_lrc.h"
#include "intel_reset.h"
#include "intel_ring.h"
@@ -392,8 +393,23 @@ void intel_engines_release(struct intel_gt *gt)
struct intel_engine_cs *engine;
enum intel_engine_id id;
+ /*
+ * Before we release the resources held by engine, we must be certain
+ * that the HW is no longer accessing them -- having the GPU scribble
+ * to or read from a page being used for something else causes no end
+ * of fun.
+ *
+ * The GPU should be reset by this point, but assume the worst just
+ * in case we aborted before completely initialising the engines.
+ */
+ GEM_BUG_ON(intel_gt_pm_is_awake(gt));
+ if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
+ __intel_gt_reset(gt, ALL_ENGINES);
+
/* Decouple the backend; but keep the layout for late GPU resets */
for_each_engine(engine, gt, id) {
+ GEM_BUG_ON(intel_engine_pm_is_awake(engine));
+
if (!engine->release)
continue;
--
2.28.0