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The effect of subsequent setup-layers executions is now either a NOOP or the minimal set of changes required to ensure layers precisely match the JSON configuration. This change allows setup-layers to be incorporated into a team's configuration management strategy. In particular, the configuration JSON manages a "pinning policy" that documents the oversight of sources of change (a requirement for embedded development in highly regulated industries). One model for this strategy would work as follows. Team level policy is developed to regularly review upstream commits that occur between the current upstream HEAD and the previously pinned revision. The JSON configuration is periodically updated after a review, test, and approval process. In the rare instance that an upstream change is considered problematic, the bbappend mechanism can be used to make relevant changes in the team's project repository. This approach also requires that team developers regularly run the project repository copy of setup-layers. This is most easily accomplished by including setup-layers in a wrapper script that all team developers use to interact with the bitbake tool suite (e.g. "bb bitbake foo-image"). Project level policy and oversight is effectively "contained" within this wrapper script, thereby reducing a significant source of human error. Left unstated, but acknowledged here, are a number of nuances required to successfully implement the above strategy. The details are out of scope for this explanation. What should be clear is that a larger configuration management strategy can now benefit from the utility provided by setup-layers. Note: Neither the above configuration management strategy example nor the change itself is intended to alter the original intent to use "bitbake-layers create-layers-setup destdir" to keep pace with upstream activity for those who wish to use it that way. (From OE-Core rev: da2e01cacd98715318a5307fe0618dbca0cf1fe7) Signed-off-by: Chuck Wolber <chuck.wolber@boeing.com> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a pre-packaged build system and development environment which is used as a development and validation tool by the Yocto Project. It features support for building customised embedded style device images and custom containers. There are reference demo images ranging from X11/GTK+ to Weston, commandline and more. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK suitable for IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of BSP layers which extend the systems capabilities in a modular way. Many layers are available and can be found through the layer index.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation, the 'meta-yocto' layer which has configuration and hardware support components. These components are all part of the Yocto Project and OpenEmbedded ecosystems.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at https://docs.yoctoproject.org/
OpenEmbedded is the build architecture used by Poky and the Yocto project. For information about OpenEmbedded, see the OpenEmbedded website.
Contribution Guidelines
The project works using a mailing list patch submission process. Patches should be sent to the mailing list for the repository the components originate from (see below). Throughout the Yocto Project, the README files in the component in question should detail where to send patches, who the maintainers are and where bugs should be reported.
A guide to submitting patches to OpenEmbedded is available at:
https://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded
There is good documentation on how to write/format patches at:
https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines
Where to Send Patches
As Poky is an integration repository (built using a tool called combo-layer), patches against the various components should be sent to their respective upstreams:
OpenEmbedded-Core (files in meta/, meta-selftest/, meta-skeleton/, scripts/):
- Git repository: https://git.openembedded.org/openembedded-core/
- Mailing list: openembedded-core@lists.openembedded.org
BitBake (files in bitbake/):
- Git repository: https://git.openembedded.org/bitbake/
- Mailing list: bitbake-devel@lists.openembedded.org
Documentation (files in documentation/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
- Mailing list: docs@lists.yoctoproject.org
meta-yocto (files in meta-poky/, meta-yocto-bsp/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto
- Mailing list: poky@lists.yoctoproject.org
If in doubt, check the openembedded-core git repository for the content you intend to modify as most files are from there unless clearly one of the above categories. Before sending, be sure the patches apply cleanly to the current git repository branch in question.