firmware-check -r
This command will display the current host firmware version.
Output for a SPARC system looks similar to:
# firmware-check -r Current host sysfw/ILOM version string: Sun System Firmware 8.3.11 2015/06/04 07:29
Output for an x86 system looks similar to:
# firmware-check -r Current host sysfw/ILOM version string: 3.2.4.28.b