LibreOffice is now ported to ppc64le. make passes, testtools passes and the resulting application is capable of headlessly converting documents to pdf. There's no reason to think it's any less capable of anything else as any other port but I don't actually have a ppc64le and transatlantic ssh tunnels aren't conducive to extensive UI testing.
The tricky bit of the port as always is the uno bridge, especially because the ABI was changed for little endian
https://bugs.openjdk.java.net/browse/JDK-8035647 is handy to get the links to the original elf v2 abi change commits to gcc/libffi
https://ghc.haskell.org/trac/ghc/ticket/8965 is handy to get a friendlier translation of the change where if gcc can see that the arguments to the function to be called will fit in registers then no argument save area is created which stumped me for a while