The OpenRISC architecture recently moved towards multicore implementations. There is a toolchain that can execute code on multiple cores in a symmetric fashion.
If you build the toolchain manually, you should use a different prefix, such as /opt/toolchains/or1k-elf-multicore and you need to build newlib with the environment variable CFLAGS="-D__OR1K_MULTICORE__":
../newlib/configure --target=or1k-elf --prefix=$PREFIX CFLAGS_FOR_TARGET="-D__OR1K_MULTICORE__"
You can install pre-compiled toolchains and install them on your Linux system. We have prebuilt-toolchains for releases of the different components that are preferably installed to /opt/toolchains/or1k-elf-multicore. You can find all releases here. Those are current releases: