I stepped back from my unified power64 koji master plan and went back to using mock configs and shell for loops. I am still using a Fedora 22 ppc64 host but now have a mock config that bootstraps against a local Fedora 19 ppc64/ppc repository. I have built half of the 2500 CentOS 7 x86_64 source rpms. Toolchain (binutils/gcc/glibc) and build group packages are solid. kernel-3.10.0-229.el7.ppc64.rpm finished this morning.
I will continue marching through the other 1200 source rpms and also build a bootable c7-ppc64 test image. After the majority of the 2500 ppc64 rpms are built, I will rebuild them in a second phase without the Fedora 19 backing repository.
config_opts['root'] = 'rhel-7b1-ppc64'
config_opts['basedir'] = '/var/lib/mock'
config_opts['target_arch'] = 'ppc64'
config_opts['legal_host_arches'] = ('ppc64',)
config_opts['chroot_setup_cmd'] = 'install bash bzip2 coreutils cpio diffutils system-release findutils gawk gcc gcc-c++ grep gzip info make patch redhat-rpm-config rpm-build sed shadow-utils tar unzip util-linux which xz'
config_opts['dist'] = 'el7' # only useful for --resultdir variable subst
config_opts['%centos_ver'] = "7"
config_opts['macros']['%centos_ver'] = "7"
config_opts['macros']['%rhel'] = "7"
config_opts['macros']['%el7'] = "1"
config_opts['macros']['%redhat'] = "7"
config_opts['macros']['%vendor'] = "CentOS"
config_opts['macros']['%packager'] = "CentOS BuildSystem <http://bugs.centos.org>"
config_opts['macros']['%_vendor'] = "redhat"
config_opts['macros']['%_vendor_host'] = "redhat"
config_opts['macros']['%_host'] = "ppc64-redhat-linux-gnu"