Hi,
I have spoke to guys responsible for FreeRTOS.
We already have FreeRTOS ported to the PPC Z4 cores – Calypso contains Z4 cores.
The only changes needed are related to the interrupt table, memory map, and sample application.
So I expect the port will be done in future.
If you can't wait, you can do it yourself as the changes which need to be done are not anyhow complicated.
Peter