PICL_PROP_SPEED
ret = add_volatile_prop(nodeh, PICL_PROP_SPEED, PICL_PTYPE_INT,
PICL_CLASS_RPM_SENSOR, (void *)PICL_PROP_SPEED,
PICL_PROP_SPEED, sun4v_env_print_sensor_callback);
PICL_PROP_SPEED, sun4v_env_print_sensor_callback);