1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/selftest_guc.c b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c
new file mode 100644
index 000000000000..bba0eafe1cdb
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c
@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2017 Intel Corporation
+ */
+
+#include "i915_selftest.h"
+#include "gem/i915_gem_pm.h"
+
+/* max doorbell number + negative test for each client type */
+#define ATTEMPTS (GUC_NUM_DOORBELLS + GUC_CLIENT_PRIORITY_NUM)
+
+static struct intel_guc_client *clients[ATTEMPTS];
+
+static bool available_dbs(struct intel_guc *guc, u32 priority)
+{
+	unsigned long offset;
+	unsigned long end;
+	u16 id;
+
+	/* first half is used for normal priority, second half for high */
+	offset = 0;
+	end = GUC_NUM_DOORBELLS / 2;
+	if (priority <= GUC_CLIENT_PRIORITY_HIGH) {
+		offset = end;
+		end += offset;
+	}
+
+	id = find_next_zero_bit(guc->doorbell_bitmap, end, offset);
+	if (id < end)
+		return true;
+
+	return false;
+}
+
+static int check_all_doorbells(struct intel_guc *guc)
+{
+	u16 db_id;
+
+	pr_info_once("Max number of doorbells: %d", GUC_NUM_DOORBELLS);
+	for (db_id = 0; db_id < GUC_NUM_DOORBELLS; ++db_id) {
+		if (!doorbell_ok(guc, db_id)) {
+			pr_err("doorbell %d, not ok\n", db_id);
+			return -EIO;
+		}
+	}
+
+	return 0;
+}
+
+static int ring_doorbell_nop(struct intel_guc_client *client)
+{
+	struct guc_process_desc *desc = __get_process_desc(client);
+	int err;
+
+	client->use_nop_wqi = true;
+
+	spin_lock_irq(&client->wq_lock);
+
+	guc_wq_item_append(client, 0, 0, 0, 0);
+	guc_ring_doorbell(client);
+
+	spin_unlock_irq(&client->wq_lock);
+
+	client->use_nop_wqi = false;
+
+	/* if there are no issues GuC will update the WQ head and keep the
+	 * WQ in active status
+	 */
+	err = wait_for(READ_ONCE(desc->head) == READ_ONCE(desc->tail), 10);
+	if (err) {
+		pr_err("doorbell %u ring failed!\n", client->doorbell_id);
+		return -EIO;
+	}
+
+	if (desc->wq_status != WQ_STATUS_ACTIVE) {
+		pr_err("doorbell %u ring put WQ in bad state (%u)!\n",
+		       client->doorbell_id, desc->wq_status);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/*
+ * Basic client sanity check, handy to validate create_clients.
+ */
+static int validate_client(struct intel_guc_client *client, int client_priority)
+{
+	if (client->priority != client_priority ||
+	    client->doorbell_id == GUC_DOORBELL_INVALID)
+		return -EINVAL;
+	else
+		return 0;
+}
+
+static bool client_doorbell_in_sync(struct intel_guc_client *client)
+{
+	return !client || doorbell_ok(client->guc, client->doorbell_id);
+}
+
+/*
+ * Check that we're able to synchronize guc_clients with their doorbells
+ *
+ * We're creating clients and reserving doorbells once, at module load. During
+ * module lifetime, GuC, doorbell HW, and i915 state may go out of sync due to
+ * GuC being reset. In other words - GuC clients are still around, but the
+ * status of their doorbells may be incorrect. This is the reason behind
+ * validating that the doorbells status expected by the driver matches what the
+ * GuC/HW have.
+ */
+static int igt_guc_clients(void *args)
+{
+	struct drm_i915_private *dev_priv = args;
+	intel_wakeref_t wakeref;
+	struct intel_guc *guc;
+	int err = 0;
+
+	GEM_BUG_ON(!HAS_GT_UC(dev_priv));
+	mutex_lock(&dev_priv->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
+
+	guc = &dev_priv->gt.uc.guc;
+	if (!guc) {
+		pr_err("No guc object!\n");
+		err = -EINVAL;
+		goto unlock;
+	}
+
+	err = check_all_doorbells(guc);
+	if (err)
+		goto unlock;
+
+	/*
+	 * Get rid of clients created during driver load because the test will
+	 * recreate them.
+	 */
+	guc_clients_disable(guc);
+	guc_clients_destroy(guc);
+	if (guc->execbuf_client) {
+		pr_err("guc_clients_destroy lied!\n");
+		err = -EINVAL;
+		goto unlock;
+	}
+
+	err = guc_clients_create(guc);
+	if (err) {
+		pr_err("Failed to create clients\n");
+		goto unlock;
+	}
+	GEM_BUG_ON(!guc->execbuf_client);
+
+	err = validate_client(guc->execbuf_client,
+			      GUC_CLIENT_PRIORITY_KMD_NORMAL);
+	if (err) {
+		pr_err("execbug client validation failed\n");
+		goto out;
+	}
+
+	/* the client should now have reserved a doorbell */
+	if (!has_doorbell(guc->execbuf_client)) {
+		pr_err("guc_clients_create didn't reserve doorbells\n");
+		err = -EINVAL;
+		goto out;
+	}
+
+	/* Now enable the clients */
+	guc_clients_enable(guc);
+
+	/* each client should now have received a doorbell */
+	if (!client_doorbell_in_sync(guc->execbuf_client)) {
+		pr_err("failed to initialize the doorbells\n");
+		err = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Basic test - an attempt to reallocate a valid doorbell to the
+	 * client it is currently assigned should not cause a failure.
+	 */
+	err = create_doorbell(guc->execbuf_client);
+
+out:
+	/*
+	 * Leave clean state for other test, plus the driver always destroy the
+	 * clients during unload.
+	 */
+	guc_clients_disable(guc);
+	guc_clients_destroy(guc);
+	guc_clients_create(guc);
+	guc_clients_enable(guc);
+unlock:
+	intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
+	mutex_unlock(&dev_priv->drm.struct_mutex);
+	return err;
+}
+
+/*
+ * Create as many clients as number of doorbells. Note that there's already
+ * client(s)/doorbell(s) created during driver load, but this test creates
+ * its own and do not interact with the existing ones.
+ */
+static int igt_guc_doorbells(void *arg)
+{
+	struct drm_i915_private *dev_priv = arg;
+	intel_wakeref_t wakeref;
+	struct intel_guc *guc;
+	int i, err = 0;
+	u16 db_id;
+
+	GEM_BUG_ON(!HAS_GT_UC(dev_priv));
+	mutex_lock(&dev_priv->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
+
+	guc = &dev_priv->gt.uc.guc;
+	if (!guc) {
+		pr_err("No guc object!\n");
+		err = -EINVAL;
+		goto unlock;
+	}
+
+	err = check_all_doorbells(guc);
+	if (err)
+		goto unlock;
+
+	for (i = 0; i < ATTEMPTS; i++) {
+		clients[i] = guc_client_alloc(guc, i % GUC_CLIENT_PRIORITY_NUM);
+
+		if (!clients[i]) {
+			pr_err("[%d] No guc client\n", i);
+			err = -EINVAL;
+			goto out;
+		}
+
+		if (IS_ERR(clients[i])) {
+			if (PTR_ERR(clients[i]) != -ENOSPC) {
+				pr_err("[%d] unexpected error\n", i);
+				err = PTR_ERR(clients[i]);
+				goto out;
+			}
+
+			if (available_dbs(guc, i % GUC_CLIENT_PRIORITY_NUM)) {
+				pr_err("[%d] non-db related alloc fail\n", i);
+				err = -EINVAL;
+				goto out;
+			}
+
+			/* expected, ran out of dbs for this client type */
+			continue;
+		}
+
+		/*
+		 * The check below is only valid because we keep a doorbell
+		 * assigned during the whole life of the client.
+		 */
+		if (clients[i]->stage_id >= GUC_NUM_DOORBELLS) {
+			pr_err("[%d] more clients than doorbells (%d >= %d)\n",
+			       i, clients[i]->stage_id, GUC_NUM_DOORBELLS);
+			err = -EINVAL;
+			goto out;
+		}
+
+		err = validate_client(clients[i], i % GUC_CLIENT_PRIORITY_NUM);
+		if (err) {
+			pr_err("[%d] client_alloc sanity check failed!\n", i);
+			err = -EINVAL;
+			goto out;
+		}
+
+		db_id = clients[i]->doorbell_id;
+
+		err = __guc_client_enable(clients[i]);
+		if (err) {
+			pr_err("[%d] Failed to create a doorbell\n", i);
+			goto out;
+		}
+
+		/* doorbell id shouldn't change, we are holding the mutex */
+		if (db_id != clients[i]->doorbell_id) {
+			pr_err("[%d] doorbell id changed (%d != %d)\n",
+			       i, db_id, clients[i]->doorbell_id);
+			err = -EINVAL;
+			goto out;
+		}
+
+		err = check_all_doorbells(guc);
+		if (err)
+			goto out;
+
+		err = ring_doorbell_nop(clients[i]);
+		if (err)
+			goto out;
+	}
+
+out:
+	for (i = 0; i < ATTEMPTS; i++)
+		if (!IS_ERR_OR_NULL(clients[i])) {
+			__guc_client_disable(clients[i]);
+			guc_client_free(clients[i]);
+		}
+unlock:
+	intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
+	mutex_unlock(&dev_priv->drm.struct_mutex);
+	return err;
+}
+
+int intel_guc_live_selftest(struct drm_i915_private *dev_priv)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(igt_guc_clients),
+		SUBTEST(igt_guc_doorbells),
+	};
+
+	if (!USES_GUC_SUBMISSION(dev_priv))
+		return 0;
+
+	return i915_subtests(tests, dev_priv);
+}