How are imx branches with extra patches created when using repo?

[JohnKlug]

I am trying to understand how I can incorporated changes into the NXP Yocto/Poky build and how repo applies changes.  I am very familiar with yocto/openembedded, but not repo.

Not sure if this is the correct forum.  But for instance:

When I do a source retrieval using NXP instructions:

repo init -u https://source.codeaurora.org/external/imx/imx-manifest -b imx-linux-zeus -m imx-5.4.24-2.1.0.xml

This creates a branch imx-linux-zeus in most if not all the submodules (if that is the correct terminology when using repo).

Where is the source for these branches, and how is it found?  They contain patches that are not in their respective git repository submodules, since the branch does not exist. 

For instance, I see in sources/poky, this is the last commit:

commit cba967414370e195d109353e51510bd829aa86c3 (HEAD, m/imx-linux-zeus)
Author: Jan Luebbe <jlu@pengutronix.de>
Date: Wed Apr 29 12:21:45 2020 +0200

openssl: upgrade 1.1.1f -> 1.1.1g

This commit does not appear to be in poky, but is here:

https://patches.openembedded.org/patch/172298/

So what is the mechanism used to apply the patches to the imx-linux-zeus branch?

[JohnKlug · Accepted solution]

Looks like I was wrong.  I did some more research and found the change on the zeus branch.

So it looks like the xml file has a revision that exists, and the source is retrieved at the specified hash.

For instance:

.repo/imx-5.4.24-2.1.0.xml

This file specifies a hash for each repository.

So it is not a mystery after all.