Many recipes based on the linux-yocto-custom.bb
recipe use Linux kernel sources that have only a single
branch - "master".
This type of repository structure is fine for linear development
supporting a single machine and architecture.
However, if you work with multiple boards and architectures,
a kernel source repository with multiple branches is more
efficient.
For example, suppose you need a series of patches for one board to boot.
Sometimes, these patches are works-in-progress or fundamentally wrong,
yet they are still necessary for specific boards.
In these situations, you most likely do not want to include these
patches in every kernel you build (i.e. have the patches as part of
the lone "master" branch).
It is situations like these that give rise to multiple branches used
within a Linux kernel sources Git repository.
Repository organization strategies exist that maximize source reuse, remove redundancy, and logically order your changes. This section presents strategies for the following cases:
Encapsulating patches in a feature description and only including the patches in the BSP descriptions of the applicable boards.
Creating a machine branch in your kernel source repository and applying the patches on that branch only.
Creating a feature branch in your kernel source repository and merging that branch into your BSP when needed.
The approach you take is entirely up to you and depends on what works best for your development model.