The linux-ppc64 buildlets run on PPC64 VMs at osuosl.org (OSU Open Source Lab).

They run Debian jessie.

Filing tickets: https://support.osuosl.org/

Machines:

go-be-1: debian@140.211.168.40
go-be-2: debian@140.211.168.41
go-be-3: debian@140.211.168.42
go-be-4: debian@140.211.168.43
go-be-5: debian@140.211.168.44

They accept ssh keys:

ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBc8FQIyzPuAFtyTmCZFpRb6YSU0qHcuq7Ms96utYfX+ bradfitz@brad5k.local
ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEodEQR84ZXQeQEaXFudopaQpvxMxzl7Q4zupODlCiX/ bradfitz@corplaptop

Log in to each and:

$ sudo ./setup.bash <BUILDKEY_HERE>