libreCMC/docs/ccs.md

CCS (Complete Corresponding Source) Requirements

As a Free Software project, libreCMC works to go above and beyond its license obligations to be a good neighbor and to promote the ideals of Free Software. The project was founded on the idea that everyone should have the freedom to control the hardware they own, which means being able to fully control what it does and what runs on it. To ensure that everyone who uses libreCMC continues to have this freedom, a mechanism was added to the build system [1] to generate a CCS disk which OEMs and others would be able to distribute with devices shipping libreCMC. This was done to ease compliance and to push the idea that sources should be provided with a device at the time of sale. Shipping a CCS disk ensures that second hand sales of the device can be compliant if the disk is handed off with the device.

make ccsdisk

A new target was created to build a CCS disk based upon the option of using an external repository or to use a local checkout. As it stands, this includes everything except for u-boot sources for a given target. In the near future, the libreCMC project will start including versions of u-boot for all officially supported targets and, going forward, make this a requirement for official hardware in libreCMC.

How to use

There are two ways to use CCS disk : enable "Build the libreCMC CCS Disk" during image configuration or run make ccsdisk after all desired firmware images have been built. Since u-boot for a given target most likely is missing, it's important that the sources for u-boot be packaged and included on the disk. To do this, make sure they are included in target/ccsdisk/files with proper documentation. To make things a little bit easier, enabling the toolchain option during image configuration and using the toolchain to build u-boot will make things go much easier if it can be done.

[1] libreCMC is a fork of OpenWrt, which both use a fork of Buildroot. Buildroot is a build system which helps to make it easier to create firmware images for "embedded" devices.