zephyr: userspace_helper: add function to add common partition to domain

Userspace_helper.h provides infrastructure to mark SOF objects
that should be accessible to all user threads (the "common_partition").

Add function user_memory_attach_common_partition() that allows to
attach this partition to a specific domain. This is intended to use
e.g. when moving LL tasks to user-space, where a single domain will
be created at boot, and should have access to the common partition.

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

Author: kv2019i

zephyr/include/rtos/userspace_helper.h

@@ -52,6 +52,18 @@ struct k_heap *module_driver_heap_init(void);
  */
 int user_memory_init_shared(k_tid_t thread_id, struct processing_module *mod);
 
+/**
+ * Attach common userspace memory partition to a module memory domain.
+ * @param dom - memory domain to attach the common partition to.
+ *
+ * @return 0 for success, error otherwise.
+ *
+ * @note
+ * Function used only when CONFIG_USERSPACE is set.
+ * The common partition contains shared objects required by user-space modules.
+ */
+int user_memory_attach_common_partition(struct k_mem_domain *dom);
+
 #endif
 
 /**

zephyr/lib/userspace_helper.c

@@ -83,6 +83,11 @@ int user_memory_init_shared(k_tid_t thread_id, struct processing_module *mod)
 	return k_mem_domain_add_thread(comp_dom, thread_id);
 }
 
+int user_memory_attach_common_partition(struct k_mem_domain *dom)
+{
+	return k_mem_domain_add_partition(dom, &common_partition);
+}
+
 int user_access_to_mailbox(struct k_mem_domain *domain, k_tid_t thread_id)
 {
 	struct k_mem_partition mem_partition;