schedule: zephyr_ll: implement scheduler_init_context()

Implement the optional scheduler_init_context() and
scheduler_free_context() ops for user-space LL scheduler.

Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>

Author: kv2019i

src/schedule/zephyr_domain.c

@@ -294,18 +294,24 @@ static int zephyr_domain_register_user(struct ll_schedule_domain *domain,
 				       void (*handler)(void *arg), void *arg)
 {
 	struct zephyr_domain *zephyr_domain = ll_sch_domain_get_pdata(domain);
-	int core = 0; /* cpu_get_id(); */
-	struct zephyr_domain_thread *dt = zephyr_domain->domain_thread + core;
+	struct zephyr_domain_thread *dt;
 	char thread_name[] = "ll_thread0";
 	k_tid_t thread;
+	int core;
 
 	tr_dbg(&ll_tr, "entry");
 
+	if (task->core < 0 || task->core >= CONFIG_CORE_COUNT)
+		return -EINVAL;
+
+	dt = zephyr_domain->domain_thread + task->core;
+
 	/* domain work only needs registered once on each core */
 	if (dt->handler)
 		return 0;
 
-	__ASSERT_NO_MSG(task->core == core);
+	/* safety check executed in kernel mode */
+	__ASSERT_NO_MSG(cpu_get_id() == core);
 
 	dt->handler = handler;
 	dt->arg = arg;

src/schedule/zephyr_ll.c

@@ -363,17 +363,7 @@ static int zephyr_ll_task_schedule_common(struct zephyr_ll *sch, struct task *ta
 
 	ret = domain_register(sch->ll_domain, task, &schedule_ll_callback, sch);
 	if (ret < 0)
-		tr_err(&ll_tr, "cannot register domain %d",
-		       ret);
-
-#if CONFIG_SOF_USERSPACE_LL
-	k_thread_access_grant(zephyr_domain_thread_tid(sch->ll_domain), sch->lock);
-
-	tr_dbg(&ll_tr, "granting access to lock %p for thread %p", sch->lock,
-	       zephyr_domain_thread_tid(sch->ll_domain));
-	tr_dbg(&ll_tr, "granting access to domain lock %p for thread %p", &sch->ll_domain->lock,
-	       zephyr_domain_thread_tid(sch->ll_domain));
-#endif
+		tr_err(&ll_tr, "cannot register domain %d", ret);
 
 	return 0;
 }
@@ -518,13 +508,49 @@ static void zephyr_ll_scheduler_free(void *data, uint32_t flags)
 		       sch->n_tasks);
 }
 
+#if CONFIG_SOF_USERSPACE_LL
+struct k_thread *zephyr_ll_init_context(void *data, struct task *task)
+{
+	struct zephyr_ll *sch = data;
+	int ret;
+
+	ret = domain_register(sch->ll_domain, task, &schedule_ll_callback, sch);
+	if (ret < 0) {
+		tr_err(&ll_tr, "cannot init_context %d", ret);
+		return NULL;
+	}
+
+	if (!k_is_user_context()) {
+		k_thread_access_grant(zephyr_domain_thread_tid(sch->ll_domain), sch->lock);
+
+		tr_dbg(&ll_tr, "granting access to lock %p for thread %p", sch->lock,
+			zephyr_domain_thread_tid(sch->ll_domain));
+		tr_dbg(&ll_tr, "granting access to domain lock %p for thread %p", &sch->ll_domain->lock,
+			zephyr_domain_thread_tid(sch->ll_domain));
+	}
+
+	return zephyr_domain_thread_tid(sch->ll_domain);
+}
+
+void zephyr_ll_free_context(void *data)
+{
+	struct zephyr_ll *sch = data;
+
+	(void *)sch;
+}
+#endif
+
 static const struct scheduler_ops zephyr_ll_ops = {
 	.schedule_task		= zephyr_ll_task_schedule,
 	.schedule_task_before	= zephyr_ll_task_schedule_before,
 	.schedule_task_after	= zephyr_ll_task_schedule_after,
 	.schedule_task_free	= zephyr_ll_task_sched_free,
 	.schedule_task_cancel	= zephyr_ll_task_cancel,
 	.scheduler_free		= zephyr_ll_scheduler_free,
+#if CONFIG_SOF_USERSPACE_LL
+	.scheduler_init_context	= zephyr_ll_init_context,
+	.scheduler_free_context	= zephyr_ll_free_context,
+#endif
 };
 
 #if CONFIG_SOF_USERSPACE_LL