1 files changed, 353 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
new file mode 100644
index 000000000000..ee9d2bcd2c13
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -0,0 +1,353 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_pm.h"
+
+#include "i915_drv.h"
+#include "i915_globals.h"
+
+#include "intel_context.h"
+#include "intel_engine.h"
+#include "intel_engine_pm.h"
+#include "intel_ring.h"
+
+static struct i915_global_context {
+	struct i915_global base;
+	struct kmem_cache *slab_ce;
+} global;
+
+static struct intel_context *intel_context_alloc(void)
+{
+	return kmem_cache_zalloc(global.slab_ce, GFP_KERNEL);
+}
+
+void intel_context_free(struct intel_context *ce)
+{
+	kmem_cache_free(global.slab_ce, ce);
+}
+
+struct intel_context *
+intel_context_create(struct i915_gem_context *ctx,
+		     struct intel_engine_cs *engine)
+{
+	struct intel_context *ce;
+
+	ce = intel_context_alloc();
+	if (!ce)
+		return ERR_PTR(-ENOMEM);
+
+	intel_context_init(ce, ctx, engine);
+	return ce;
+}
+
+int __intel_context_do_pin(struct intel_context *ce)
+{
+	int err;
+
+	if (mutex_lock_interruptible(&ce->pin_mutex))
+		return -EINTR;
+
+	if (likely(!atomic_read(&ce->pin_count))) {
+		intel_wakeref_t wakeref;
+
+		if (unlikely(!test_bit(CONTEXT_ALLOC_BIT, &ce->flags))) {
+			err = ce->ops->alloc(ce);
+			if (unlikely(err))
+				goto err;
+
+			__set_bit(CONTEXT_ALLOC_BIT, &ce->flags);
+		}
+
+		err = 0;
+		with_intel_runtime_pm(ce->engine->uncore->rpm, wakeref)
+			err = ce->ops->pin(ce);
+		if (err)
+			goto err;
+
+		GEM_TRACE("%s context:%llx pin ring:{head:%04x, tail:%04x}\n",
+			  ce->engine->name, ce->timeline->fence_context,
+			  ce->ring->head, ce->ring->tail);
+
+		i915_gem_context_get(ce->gem_context); /* for ctx->ppgtt */
+
+		smp_mb__before_atomic(); /* flush pin before it is visible */
+	}
+
+	atomic_inc(&ce->pin_count);
+	GEM_BUG_ON(!intel_context_is_pinned(ce)); /* no overflow! */
+
+	mutex_unlock(&ce->pin_mutex);
+	return 0;
+
+err:
+	mutex_unlock(&ce->pin_mutex);
+	return err;
+}
+
+void intel_context_unpin(struct intel_context *ce)
+{
+	if (likely(atomic_add_unless(&ce->pin_count, -1, 1)))
+		return;
+
+	/* We may be called from inside intel_context_pin() to evict another */
+	intel_context_get(ce);
+	mutex_lock_nested(&ce->pin_mutex, SINGLE_DEPTH_NESTING);
+
+	if (likely(atomic_dec_and_test(&ce->pin_count))) {
+		GEM_TRACE("%s context:%llx retire\n",
+			  ce->engine->name, ce->timeline->fence_context);
+
+		ce->ops->unpin(ce);
+
+		i915_gem_context_put(ce->gem_context);
+		intel_context_active_release(ce);
+	}
+
+	mutex_unlock(&ce->pin_mutex);
+	intel_context_put(ce);
+}
+
+static int __context_pin_state(struct i915_vma *vma)
+{
+	u64 flags;
+	int err;
+
+	flags = i915_ggtt_pin_bias(vma) | PIN_OFFSET_BIAS;
+	flags |= PIN_HIGH | PIN_GLOBAL;
+
+	err = i915_vma_pin(vma, 0, 0, flags);
+	if (err)
+		return err;
+
+	/*
+	 * And mark it as a globally pinned object to let the shrinker know
+	 * it cannot reclaim the object until we release it.
+	 */
+	i915_vma_make_unshrinkable(vma);
+	vma->obj->mm.dirty = true;
+
+	return 0;
+}
+
+static void __context_unpin_state(struct i915_vma *vma)
+{
+	i915_vma_make_shrinkable(vma);
+	__i915_vma_unpin(vma);
+}
+
+__i915_active_call
+static void __intel_context_retire(struct i915_active *active)
+{
+	struct intel_context *ce = container_of(active, typeof(*ce), active);
+
+	GEM_TRACE("%s context:%llx retire\n",
+		  ce->engine->name, ce->timeline->fence_context);
+
+	if (ce->state)
+		__context_unpin_state(ce->state);
+
+	intel_timeline_unpin(ce->timeline);
+	intel_ring_unpin(ce->ring);
+
+	intel_context_put(ce);
+}
+
+static int __intel_context_active(struct i915_active *active)
+{
+	struct intel_context *ce = container_of(active, typeof(*ce), active);
+	int err;
+
+	intel_context_get(ce);
+
+	err = intel_ring_pin(ce->ring);
+	if (err)
+		goto err_put;
+
+	err = intel_timeline_pin(ce->timeline);
+	if (err)
+		goto err_ring;
+
+	if (!ce->state)
+		return 0;
+
+	err = __context_pin_state(ce->state);
+	if (err)
+		goto err_timeline;
+
+	return 0;
+
+err_timeline:
+	intel_timeline_unpin(ce->timeline);
+err_ring:
+	intel_ring_unpin(ce->ring);
+err_put:
+	intel_context_put(ce);
+	return err;
+}
+
+int intel_context_active_acquire(struct intel_context *ce)
+{
+	int err;
+
+	err = i915_active_acquire(&ce->active);
+	if (err)
+		return err;
+
+	/* Preallocate tracking nodes */
+	if (!i915_gem_context_is_kernel(ce->gem_context)) {
+		err = i915_active_acquire_preallocate_barrier(&ce->active,
+							      ce->engine);
+		if (err) {
+			i915_active_release(&ce->active);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+void intel_context_active_release(struct intel_context *ce)
+{
+	/* Nodes preallocated in intel_context_active() */
+	i915_active_acquire_barrier(&ce->active);
+	i915_active_release(&ce->active);
+}
+
+void
+intel_context_init(struct intel_context *ce,
+		   struct i915_gem_context *ctx,
+		   struct intel_engine_cs *engine)
+{
+	struct i915_address_space *vm;
+
+	GEM_BUG_ON(!engine->cops);
+
+	kref_init(&ce->ref);
+
+	ce->gem_context = ctx;
+	rcu_read_lock();
+	vm = rcu_dereference(ctx->vm);
+	if (vm)
+		ce->vm = i915_vm_get(vm);
+	else
+		ce->vm = i915_vm_get(&engine->gt->ggtt->vm);
+	rcu_read_unlock();
+	if (ctx->timeline)
+		ce->timeline = intel_timeline_get(ctx->timeline);
+
+	ce->engine = engine;
+	ce->ops = engine->cops;
+	ce->sseu = engine->sseu;
+	ce->ring = __intel_context_ring_size(SZ_16K);
+
+	INIT_LIST_HEAD(&ce->signal_link);
+	INIT_LIST_HEAD(&ce->signals);
+
+	mutex_init(&ce->pin_mutex);
+
+	i915_active_init(&ce->active,
+			 __intel_context_active, __intel_context_retire);
+}
+
+void intel_context_fini(struct intel_context *ce)
+{
+	if (ce->timeline)
+		intel_timeline_put(ce->timeline);
+	i915_vm_put(ce->vm);
+
+	mutex_destroy(&ce->pin_mutex);
+	i915_active_fini(&ce->active);
+}
+
+static void i915_global_context_shrink(void)
+{
+	kmem_cache_shrink(global.slab_ce);
+}
+
+static void i915_global_context_exit(void)
+{
+	kmem_cache_destroy(global.slab_ce);
+}
+
+static struct i915_global_context global = { {
+	.shrink = i915_global_context_shrink,
+	.exit = i915_global_context_exit,
+} };
+
+int __init i915_global_context_init(void)
+{
+	global.slab_ce = KMEM_CACHE(intel_context, SLAB_HWCACHE_ALIGN);
+	if (!global.slab_ce)
+		return -ENOMEM;
+
+	i915_global_register(&global.base);
+	return 0;
+}
+
+void intel_context_enter_engine(struct intel_context *ce)
+{
+	intel_engine_pm_get(ce->engine);
+	intel_timeline_enter(ce->timeline);
+}
+
+void intel_context_exit_engine(struct intel_context *ce)
+{
+	intel_timeline_exit(ce->timeline);
+	intel_engine_pm_put(ce->engine);
+}
+
+int intel_context_prepare_remote_request(struct intel_context *ce,
+					 struct i915_request *rq)
+{
+	struct intel_timeline *tl = ce->timeline;
+	int err;
+
+	/* Only suitable for use in remotely modifying this context */
+	GEM_BUG_ON(rq->hw_context == ce);
+
+	if (rcu_access_pointer(rq->timeline) != tl) { /* timeline sharing! */
+		err = mutex_lock_interruptible_nested(&tl->mutex,
+						      SINGLE_DEPTH_NESTING);
+		if (err)
+			return err;
+
+		/* Queue this switch after current activity by this context. */
+		err = i915_active_fence_set(&tl->last_request, rq);
+		mutex_unlock(&tl->mutex);
+		if (err)
+			return err;
+	}
+
+	/*
+	 * Guarantee context image and the timeline remains pinned until the
+	 * modifying request is retired by setting the ce activity tracker.
+	 *
+	 * But we only need to take one pin on the account of it. Or in other
+	 * words transfer the pinned ce object to tracked active request.
+	 */
+	GEM_BUG_ON(i915_active_is_idle(&ce->active));
+	return i915_active_add_request(&ce->active, rq);
+}
+
+struct i915_request *intel_context_create_request(struct intel_context *ce)
+{
+	struct i915_request *rq;
+	int err;
+
+	err = intel_context_pin(ce);
+	if (unlikely(err))
+		return ERR_PTR(err);
+
+	rq = i915_request_create(ce);
+	intel_context_unpin(ce);
+
+	return rq;
+}
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include "selftest_context.c"
+#endif