Linux gained support for little endian on IBM Power server CPUs in late 2013, in the lead-up to the release of the POWER8, where LE became the officially recomm

Linux gained support for little endian on IBM Power server CPUs in late 2013, in the lead-up to the release of the POWER8, where LE became the officially recommended option for running Linux. As you say, it's selectable at build time.