2.2. Building Documentation

To create a rendered copy of this documentation locally you can use the Sphinx tool to build and package the plain-text documents into HTML-formatted pages.

If you are building the documentation for the first time then you will need to check that you have the required software packages, as described in the Prerequisites section that follows.


An online copy of the documentation is available at https://www.trustedfirmware.org/docs/tf-a, if you want to view a rendered copy without doing a local build.

2.2.1. Prerequisites

For building a local copy of the TF-A documentation you will need:

  • Python 3 (3.5 or later)

  • PlantUML (1.2017.15 or later)

  • Python modules specified in docs/requirements.txt

    You can install these with pip3 (the Python Package Installer) by passing it the requirements file above (with -r). An optional --user argument will install them locally, but you have to add their location to $PATH (pip will emit a warning). Alternatively, they can be installed globally (but will probably require root privileges).


    Although not necessary, it is recommended you use a virtual environment. More advanced usage instructions for pip are beyond the scope of this document but you can refer to the pip homepage for detailed guides.

  • Optionally, the Dia application can be installed if you need to edit existing .dia diagram files, or create new ones.

An example set of installation commands for Ubuntu follows, assuming that the working directory is docs:

sudo apt install python3 python3-pip plantuml [dia]
pip3 install [--user] -r requirements.txt


Several other modules will be installed as dependencies. Please review the list to ensure that there will be no conflicts with other modules already installed in your environment.

2.2.2. Building rendered documentation

Documents can be built into HTML-formatted pages from project root directory by running the following command.

make doc

Output from the build process will be placed in:


We also support building documentation in other formats. From the docs directory of the project, run the following command to see the supported formats. It is important to note that you will not get the correct result if the command is run from the project root directory, as that would invoke the top-level Makefile for TF-A itself.

make help

2.2.3. Building rendered documentation from a container

There may be cases where you can not either install or upgrade required dependencies to generate the documents, so in this case, one way to create the documentation is through a docker container. The first step is to check if docker is installed in your host, otherwise check main docker page for installation instructions. Once installed, run the following script from project root directory

docker run --rm -v $PWD:/TF sphinxdoc/sphinx \
       bash -c 'cd /TF && \
       pip3 install plantuml -r ./docs/requirements.txt && make doc'

The above command fetches the sphinxdoc/sphinx container from docker hub, launches the container, installs documentation requirements and finally creates the documentation. Once done, exit the container and output from the build process will be placed in:


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