Venus OS: the Victron Energy Unix like distro with a linux kernel

The problematic part with this name is that it is from the Roman mythology and not, as most of our products, from the Greek. Phoenix is already taken though by a charger...

First of all, make sure you really want to rebuild a complete rootfs, it takes time to compile, lots of diskspace and results in an image / sdk which already available anyway, in binary form.

Anyway, if you insist: this repo is the starting point to build Venus. It contains wrapper functions around bitbake and git to fetch, and compile sources.

For a complete build you need to have access to private repros of Victron Energy. Building only opensource packages is also possible (but not checked automatically at the moment).

For further documentation on Venus, see the Venus OS wiki.

Venus uses the OpenEmbedded, the Yocto Project build system architecture. For an introduction, start with reading their wiki and the glossary.

Getting started

Building Venus requires a Linux. At Victron we use Ubuntu for this.

# clone this repository
git clone https://github.com/victronenergy/venus.git
cd venus

# install host packages (Debian based)
sudo make prereq

# fetch needed subtrees
# use make fetch-all instead, if you have access to all the private repos.
make fetch

That last fetch command has cloned several things into the ./sources/ directory. First of all there is bitbake, which is a make-like build tool part of OpenEmbedded. Besides that, you'll find openembedded-core and various other layers containing recipes and other metadata defining Venus.

Now its time to actually start building (which can take many hours). Select one of below example commands:

# build all, this will take a while though... it builds for all MACHINES as found
# in conf/machines.
make venus-images

# build for a specific machine
make ccgx-venus-image
make beaglebone-venus-image

# build the swu file only
make ccgx-swu

# build from within the bitbake shell.
# this will have the same end result as make ccgx-swu
make ccgx-bb
bitbake venus-swu

Configs

Above Getting Started instructions will automatically select the config that is used for Venus OS as distributed. Alternative setups can also be used, e.g. to build for a newer OE version:

make CONFIG=rocko fetch-all

To see which config your checkout is using, look at the ./conf symlink. It will link to one of the configs in the ./configs directories.

For each config there are a few files:

• repos.conf contains the repositories which need to be checked out. It can be rebuild with make update-repos.conf.
• metas.whitelist contains the meta directory which will be added to bblayers.conf, but only if they are actually present.
• machines contains a list of machines that can be build in this config

To add a new repository, put it in sources, then checkout the branch you want and set an upstream branch. The result can be made permanent with: make repos.conf.

Don't forget to add the directories you want to use from the new repository to metas.whitelist.

Using the repos command

Repos is just like git submodule foreach -q git, but shorter, so you can do:

./repos push origin ./repos tag xyz

it will push all, tag all etc. Likewise you can revert to a certain revision with:

./repos checkout tagname

managing git remotes and branches

# patches not in upstream yet
./repos cherry -v

# local changes with respect to upstream
./repos diff @{u}

# local changes with respect to the push branch
./repos diff 'origin/`git rev-parse --abbrev-ref HEAD`'
or if you have git 2.5+ ./repos diff @{push}

./repos log @{u}..upstream/`git rev-parse --abbrev-ref @{u} | grep -o "[a-Z0-9]*$"` --oneline

Releasing

# tag & push venus repo as well as all repos.

git tag v2.21
git push origin v2.21

./repos tag v2.21
./repos push origin v2.21

Maintenance releases

As a rule, the base branch on which the maintenance releases will be based is prefixed with a b.

This example shows how to create a new maintenance branch. The context is that master is already working on v2.30. Latest official release was v2.20. So we make a branch named b2.20 in which the first release will be v2.21; later if another maintenance release is necessary v2.22 is pushed on top; and so forth.

# clone, prep and push the venus repo
git clone [email protected]:victronenergy/venus.git venus-b2.20
git checkout v2.20
git checkout -b b2.20
git push --set-upstream origin b2.20

# fetch all the meta repos
make fetch-all

# clone, prep and push them
./repos checkout v2.20
./repos checkout -b b2.20
./repos push --set-upstream origin b2.20

Now you're all set; and ready to start cherry-picking.

The eight golden rules of maintaining the maintenance branch

1. only take changes from master: cherry-picking
2. don't add changes or new versions that are not in master yet
3. git cherry-pick -x appends a nice (cherry-picked from [ref]) line to the commit message
4. add and/or increase the PR when adding patches
5. drop the PR again when going to a clean version
6. when adding patches; add a backported from note just like this one to the commit message
7. go through the todo where the team is working on master, and add (**backported to v2.22**) to each and every patch and version thats been backported
8. double verify everything by cross referencing the todo, the commits logs from master as well as your own

And the master rule: changes need to be either really small, well tested or very important

Various notes

1. Linux update

If you encounter problems like this:

• Solver encountered 1 problem(s):
• Problem 1/1:
• • nothing provides kernel-image-4.14.67 needed by packagegroup-machine-base-1.0-r83.einstein

if can be fixed with: make einstein-bb bitbake -c cleanall packagegroup-machine-base

and thereafter try again