- * @brief Mark the device definition should be loaded automatically as earlier
- * as possible in the kernel bootstrapping stage (before initialization of file
- * systems). Load here if your driver is standalone and require no other than
- * basic memory allocation services
+ * @brief Mark the device definition to be loaded as system configuration
+ * device. These kind of devices are defined to be the devices that talk to the
+ * system firmware to do config, or collecting crucial information about the
+ * system. For instances, ACPI, SoC components, and other **interconnection**
+ * buese (not USB!). Such device driver must only rely on basic memory
+ * management service, and must not try accessing subsystems other than the mm
+ * unit, for example, timer, interrupt, file-system, must not assumed exist.