doc: add contributing non-Apache2.0 docs

CONTRIBUTING.rst

@@ -22,21 +22,51 @@ software continues to be available under the terms that the author desired.
 
 .. _GitHub repo: https://github.com/zephyrproject-rtos/zephyr
 
-Zephyr uses the `Apache 2.0 license`_ (as found in the LICENSE file in the
-project's `GitHub repo`_) to strike a balance between open contribution and
-allowing you to use the software however you would like to. There are some
-imported or reused components of the Zephyr project that use other licensing,
-as described in `Zephyr Licensing`_.
-
-.. _Zephyr Licensing:
-   https://www.zephyrproject.org/doc/LICENSING.html
-
-The license tells you what rights you have as a developer, provided by the
+Zephyr uses the `Apache 2.0 license`_ (as found in the LICENSE file in
+the project's `GitHub repo`_) to strike a balance between open
+contribution and allowing you to use the software however you would like
+to.  The Apache 2.0 license is a permisive open source license that
+allows you to freely use, modify, distribute and sell your own products
+that include Apache 2.0 licensed software.  (For more information about
+this, check out articles such as `Why choose Apache 2.0 licensing`_ and
+`Top 10 Apache License Questions Answered`_).
+
+.. _Why choose Apache 2.0 licensing:
+   https://www.zephyrproject.org/about/faq/what-rationale-choosing-apache-20-license
+
+.. _Top 10 Apache License Questions Answered:
+   https://www.whitesourcesoftware.com/whitesource-blog/top-10-apache-license-questions-answered/
+
+A license tells you what rights you have as a developer, as provided by the
 copyright holder. It is important that the contributor fully understands the
 licensing rights and agrees to them. Sometimes the copyright holder isn't the
 contributor, such as when the contributor is doing work on behalf of a
 company.
 
+Components using other Licenses
+===============================
+
+There are some imported or reused components of the Zephyr project that
+use other licensing, as described in `Zephyr Licensing`_.
+
+.. _Zephyr Licensing:
+   https://www.zephyrproject.org/doc/LICENSING.html
+
+Importing code into the Zephyr OS from other projects that use a license
+other than the Apache 2.0 license needs to be fully understood in
+context and approved by the Zephyr governing board.
+
+By carefully reviewing potential contributions and also enforcing
+`developer attestations <DCO>`_ for contributed code, we can ensure that
+the Zephyr community can develop products with the Zephyr Project
+without concerns over patent or copyright issues.
+
+See `Contributing non-Apache 2.0 components`_ for more information about
+this contributing and review process for imported components.
+
+.. _Contributing non-Apache 2.0 components:
+   https://www.zephyrproject.org/doc/contribute/contribute_non-apache.html
+
 .. _DCO:
 
 Developer Certification of Origin (DCO)
@@ -248,6 +278,8 @@ it when committing code, edit your *.git/hooks/pre-commit* file to contain:
     set -e exec
     exec git diff --cached | ${ZEPHYR_BASE}/scripts/checkpatch.pl - || true
 
+.. _Contribution workflow:
+
 Contribution Workflow
 *********************
 

doc/contribute/code_component_README

@@ -0,0 +1,50 @@
+[Code Component Name]
+#####################
+
+Origin:
+   [Name of project hosting the original open source code]
+   [Provide a link to the source]
+
+Status:
+   [Current version of this component, supported by Zephyr]
+
+Purpose:
+   [Brief description of what this software does]
+
+Description:
+   [Long description that will help reviewers discuss suitability of the
+   package to solve the problem at hand (there may be a better package
+   available.)
+
+   What is its primary functionality (e.g., SQLLite is a lightweight
+   database)?
+
+   What problem are you trying to solve? (e.g., a state store is
+   required to maintain ...)
+
+   Why is this the right package to solve it (e.g., SQLite is small,
+   easy to use, and has a very liberal license.)]
+
+Dependencies:
+   [What other components does this package depend on? Does the software
+   include any dynamic or static linking, or automatic downloading of any
+   code?
+
+   Will the Zephyr project have a direct dependency on the component, or
+   will it be included via an abstraction layer with this component as a
+   replacable implementation?]
+
+URL:
+   [location to the project's home, e.g., a github repo]
+
+commit:
+   [08ded7f21529c39e5133688ffb9a9d0c94e5c6e]
+
+Maintained-by:
+   [External]
+
+License:
+   [use SPDX identifier (https://spdx.org/licenses/), such as BSD-3-Clause]
+
+License Link:
+   [link to the project's LICENSE file, e.g., https://github.com/xyz/LICENSE]

doc/contribute/contribute.rst

@@ -10,3 +10,4 @@ patches for code, documentation, tests, and more, directly to the project.
    :maxdepth: 1
 
    contribute_guidelines.rst
+   contribute_non-apache.rst

doc/contribute/contribute_non-apache.rst

@@ -0,0 +1,77 @@
+.. _contribute_non-Apache:
+
+Contributing non-Apache 2.0 licensed components
+###############################################
+
+Importing code into the Zephyr OS from other projects that use a license
+other than the Apache 2.0 license needs to be fully understood in
+context and approved by the `Zephyr governing board`_.
+
+.. _Zephyr governing board:
+   https://www.zephyrproject.org/about/organization
+
+By carefully reviewing potential contributions and also enforcing a
+:ref:`DCO` for contributed code, we ensure that
+the Zephyr community can develop products with the Zephyr Project
+without concerns over patent or copyright issues.
+
+Submission and review process
+*****************************
+
+All contributions to the Zephyr project are submitted through GitHub
+pull requests (PR) following the Zephyr Project's :ref:`Contribution workflow`.
+
+Before you begin working on including a new component to the Zephyr
+Project (Apache-2.0 licensed or not), you should start up a conversation
+on the `developer mailing list <https://lists.zephyrproject.org>`_
+to see what the Zephyr community thinks about the idea.  Maybe there's
+someone else working on something similar you can collaborate with, or a
+different approach may make the new component unnecessary.
+
+If the conclusion is that including a new component is the best
+solution, and this new component uses a license other than Apache-2.0,
+these additional steps must be followed:
+
+#. Complete a README for your code component and add it to your source
+   code pull request (PR).  A recommended README template can be found in
+   :file:`doc/contributing/code_component_README` (and included
+   `below`_ for reference)
+
+#. The Zephyr Techincal Steering Committee (TSC) will evaluate the code
+   component README as part of the PR
+   commit and vote on accepting it using the GitHub PR review tools.
+
+   - If rejected by the TSC, a TSC member will communicate this to
+     the contributor and the PR will be closed.
+
+   - If approved by the TSC, the TSC chair will forward the README to
+     the Zephyr governing board for further review.
+
+#. The Zephyr governing board has two weeks to review and ask questions:
+
+   - If there are no objections, the matter is closed. Approval can be
+     accelerated by unanimous approval of the board before the two
+     weeks are up.
+
+   - If a governing board member raises an objection that cannot be resolved
+     via email, the board will meet to discuss whether to override the
+     TSC approval or identify other approaches that can resolve the
+     objections.
+
+#. On approval of the Zephyr TSC and governing board, final review of
+   the PR may be made to ensure its proper placement in the
+   Zephyr Project :ref:`source_tree_v2`, (in the ``ext`` folder), and
+   inclusion in the :ref:`zephyr_licensing` document.
+
+.. note::
+
+   External components not under the Apache-2.0 license **cannot** be
+   included in a Zephyr OS release without approval of both the Zephyr TSC
+   and the Zephyr governing board.
+
+.. _below:
+
+Code component README template
+******************************
+
+.. literalinclude:: code_component_README