To obtain the source code, you must use Git:
git clone https://github.com/open-power/occ.git
Obtain a current version of the GNU powerpc cross compiler
Goto the src/ directory of the Git repository
Build the binary files: make all
Combine the binaries: make combineImage NOTE: This creates the OCC binary: image.bin
Create the string file for tracing: make tracehash NOTE: This creates the debug trace hash file: occStringFile
Repackage the PNOR to contain modified OCC image: op-build occ-rebuild openpower-pnor-rebuild
Documentation can be found in the docs project of the open-power repository. https://github.com/open-power/docs/tree/master/occ
See the LICENSE file.