You must install all the firmware for your server at the same time. You cannot install an individual system firmware component, such as Oracle ILOM.
Refer to the information about downloading product software and firmware in the product notes for your server or in the Oracle ILOM Administrator's Guide for Configuration and Maintenance.
Refer to the information about performing firmware updates in the Oracle ILOM Administrator's Guide for Configuration and Maintenance. Ensure that you perform the preparatory steps described in that document before updating the firmware.