9 files changed, 101 insertions, 15 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index bb1c1adad78a..8acb922b69f9 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -648,6 +648,8 @@ static int init_status_page(struct intel_engine_cs *engine)
 	void *vaddr;
 	int ret;
 
+	INIT_LIST_HEAD(&engine->status_page.timelines);
+
 	/*
 	 * Though the HWS register does support 36bit addresses, historically
 	 * we have had hangs and corruption reported due to wild writes if
@@ -830,6 +832,21 @@ create_pinned_context(struct intel_engine_cs *engine,
 	return ce;
 }
 
+static void destroy_pinned_context(struct intel_context *ce)
+{
+	struct intel_engine_cs *engine = ce->engine;
+	struct i915_vma *hwsp = engine->status_page.vma;
+
+	GEM_BUG_ON(ce->timeline->hwsp_ggtt != hwsp);
+
+	mutex_lock(&hwsp->vm->mutex);
+	list_del(&ce->timeline->engine_link);
+	mutex_unlock(&hwsp->vm->mutex);
+
+	intel_context_unpin(ce);
+	intel_context_put(ce);
+}
+
 static struct intel_context *
 create_kernel_context(struct intel_engine_cs *engine)
 {
@@ -926,7 +943,6 @@ void intel_engine_cleanup_common(struct intel_engine_cs *engine)
 	GEM_BUG_ON(!list_empty(&engine->active.requests));
 	tasklet_kill(&engine->execlists.tasklet); /* flush the callback */
 
-	cleanup_status_page(engine);
 	intel_breadcrumbs_free(engine->breadcrumbs);
 
 	intel_engine_fini_retire(engine);
@@ -935,11 +951,11 @@ void intel_engine_cleanup_common(struct intel_engine_cs *engine)
 	if (engine->default_state)
 		fput(engine->default_state);
 
-	if (engine->kernel_context) {
-		intel_context_unpin(engine->kernel_context);
-		intel_context_put(engine->kernel_context);
-	}
+	if (engine->kernel_context)
+		destroy_pinned_context(engine->kernel_context);
+
 	GEM_BUG_ON(!llist_empty(&engine->barrier_tasks));
+	cleanup_status_page(engine);
 
 	intel_wa_list_free(&engine->ctx_wa_list);
 	intel_wa_list_free(&engine->wa_list);
@@ -1274,8 +1290,12 @@ void intel_engines_reset_default_submission(struct intel_gt *gt)
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
 
-	for_each_engine(engine, gt, id)
+	for_each_engine(engine, gt, id) {
+		if (engine->sanitize)
+			engine->sanitize(engine);
+
 		engine->set_default_submission(engine);
+	}
 }
 
 bool intel_engine_can_store_dword(struct intel_engine_cs *engine)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
index d74e748f677a..8b353bc8c100 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
@@ -60,6 +60,13 @@ static int __engine_unpark(struct intel_wakeref *wf)
 
 		/* Scrub the context image after our loss of control */
 		ce->ops->reset(ce);
+
+		CE_TRACE(ce, "reset { seqno:%x, *hwsp:%x, ring:%x }\n",
+			 ce->timeline->seqno,
+			 READ_ONCE(*ce->timeline->hwsp_seqno),
+			 ce->ring->emit);
+		GEM_BUG_ON(ce->timeline->seqno !=
+			   READ_ONCE(*ce->timeline->hwsp_seqno));
 	}
 
 	if (engine->unpark)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index ee6312601c56..02ee1e736982 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -68,6 +68,7 @@ typedef u8 intel_engine_mask_t;
 #define ALL_ENGINES ((intel_engine_mask_t)~0ul)
 
 struct intel_hw_status_page {
+	struct list_head timelines;
 	struct i915_vma *vma;
 	u32 *addr;
 };
diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
index 358fd2455f6e..695a2d566d76 100644
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
@@ -2698,6 +2698,14 @@ static void reset_csb_pointers(struct intel_engine_cs *engine)
 	GEM_BUG_ON(READ_ONCE(*execlists->csb_write) != reset_value);
 }
 
+static void sanitize_hwsp(struct intel_engine_cs *engine)
+{
+	struct intel_timeline *tl;
+
+	list_for_each_entry(tl, &engine->status_page.timelines, engine_link)
+		intel_timeline_reset_seqno(tl);
+}
+
 static void execlists_sanitize(struct intel_engine_cs *engine)
 {
 	GEM_BUG_ON(execlists_active(&engine->execlists));
@@ -2721,7 +2729,7 @@ static void execlists_sanitize(struct intel_engine_cs *engine)
 	 * that may be lost on resume/initialisation, and so we need to
 	 * reset the value in the HWSP.
 	 */
-	intel_timeline_reset_seqno(engine->kernel_context->timeline);
+	sanitize_hwsp(engine);
 
 	/* And scrub the dirty cachelines for the HWSP */
 	clflush_cache_range(engine->status_page.addr, PAGE_SIZE);
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 35f4352a484f..008f50a86355 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -885,7 +885,6 @@ err_vma:
 
 void lrc_reset(struct intel_context *ce)
 {
-	CE_TRACE(ce, "reset\n");
 	GEM_BUG_ON(!intel_context_is_pinned(ce));
 
 	intel_ring_reset(ce->ring, ce->ring->emit);
diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 5105e19514ee..4ea741f488a8 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -321,6 +321,39 @@ out:
 	return ret;
 }
 
+static void sanitize_hwsp(struct intel_engine_cs *engine)
+{
+	struct intel_timeline *tl;
+
+	list_for_each_entry(tl, &engine->status_page.timelines, engine_link)
+		intel_timeline_reset_seqno(tl);
+}
+
+static void xcs_sanitize(struct intel_engine_cs *engine)
+{
+	/*
+	 * Poison residual state on resume, in case the suspend didn't!
+	 *
+	 * We have to assume that across suspend/resume (or other loss
+	 * of control) that the contents of our pinned buffers has been
+	 * lost, replaced by garbage. Since this doesn't always happen,
+	 * let's poison such state so that we more quickly spot when
+	 * we falsely assume it has been preserved.
+	 */
+	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+		memset(engine->status_page.addr, POISON_INUSE, PAGE_SIZE);
+
+	/*
+	 * The kernel_context HWSP is stored in the status_page. As above,
+	 * that may be lost on resume/initialisation, and so we need to
+	 * reset the value in the HWSP.
+	 */
+	sanitize_hwsp(engine);
+
+	/* And scrub the dirty cachelines for the HWSP */
+	clflush_cache_range(engine->status_page.addr, PAGE_SIZE);
+}
+
 static void reset_prepare(struct intel_engine_cs *engine)
 {
 	struct intel_uncore *uncore = engine->uncore;
@@ -1070,6 +1103,8 @@ static void setup_common(struct intel_engine_cs *engine)
 	setup_irq(engine);
 
 	engine->resume = xcs_resume;
+	engine->sanitize = xcs_sanitize;
+
 	engine->reset.prepare = reset_prepare;
 	engine->reset.rewind = reset_rewind;
 	engine->reset.cancel = reset_cancel;
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index a005d0165bf4..7fe05918a76e 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -319,6 +319,25 @@ __intel_timeline_create(struct intel_gt *gt,
 	return timeline;
 }
 
+struct intel_timeline *
+intel_timeline_create_from_engine(struct intel_engine_cs *engine,
+				  unsigned int offset)
+{
+	struct i915_vma *hwsp = engine->status_page.vma;
+	struct intel_timeline *tl;
+
+	tl = __intel_timeline_create(engine->gt, hwsp, offset);
+	if (IS_ERR(tl))
+		return tl;
+
+	/* Borrow a nearby lock; we only create these timelines during init */
+	mutex_lock(&hwsp->vm->mutex);
+	list_add_tail(&tl->engine_link, &engine->status_page.timelines);
+	mutex_unlock(&hwsp->vm->mutex);
+
+	return tl;
+}
+
 void __intel_timeline_pin(struct intel_timeline *tl)
 {
 	GEM_BUG_ON(!atomic_read(&tl->pin_count));
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.h b/drivers/gpu/drm/i915/gt/intel_timeline.h
index 634acebd0c4b..f502a619843f 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline.h
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.h
@@ -44,14 +44,9 @@ intel_timeline_create(struct intel_gt *gt)
 	return __intel_timeline_create(gt, NULL, 0);
 }
 
-static inline struct intel_timeline *
+struct intel_timeline *
 intel_timeline_create_from_engine(struct intel_engine_cs *engine,
-				  unsigned int offset)
-{
-	return __intel_timeline_create(engine->gt,
-				       engine->status_page.vma,
-				       offset);
-}
+				  unsigned int offset);
 
 static inline struct intel_timeline *
 intel_timeline_get(struct intel_timeline *timeline)
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline_types.h b/drivers/gpu/drm/i915/gt/intel_timeline_types.h
index 4474f487f589..e360f50706bf 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_timeline_types.h
@@ -84,6 +84,8 @@ struct intel_timeline {
 	struct list_head link;
 	struct intel_gt *gt;
 
+	struct list_head engine_link;
+
 	struct kref kref;
 	struct rcu_head rcu;
 };