Re: is there a recent explanation of tricks you can play with MACHINEOVERRIDES?


Robert P. J. Day
 

On Sat, 20 Mar 2021, Quentin Schulz wrote:

Hi Robert,

On March 19, 2021 9:54:34 AM UTC, "Robert P. J. Day" <rpjday@crashcourse.ca> wrote:

years ago, i asked about how to support a small set of
closely-related targets using MACHINEOVERRIDES to define how to apply
patches in a (somewhat) hierarchical fashion:

https://www.yoctoproject.org/pipermail/yocto/2016-March/028922.html

is there any current BSP that does something like that? and is this
sort of thing worth expanding on and adding to one of the manuals?
Don't use _prepend but =. BEFORE the other includes in your machine
configuration files otherwise the order in MACHINEOVERRIDES is
incorrect. Do NOT use append, or .=, they result in incorrect order
too.
i did write that a while back while i was still figuring it out. :-)

I do use this mechanism because we kind of use Yocto machines the
wrong way (basically using machines instead of distros or more
complex images).

I think NXP is making extensive use of this variable by defining a
MACHINEOVERRIDES per SoC families (e.g. imx:imx8:imx8mm).

I'm not sure we need to explain all possible uses of OVERRIDES
variables, just how to set it and how it works.
i agree that it would be inappropriate in the *regular* sections of
the docs, but i'm convinced it would be worth explaining in some sort
of "advanced features" section. after all, you just admitted that
*you* use it, and that NXP uses it. that should be enough to justify
explaining it *somewhere*, no?

rday

Join yocto@lists.yoctoproject.org to automatically receive all group messages.