[meta-freescale] Please explain the logic on the MACHINEOVERRIDES ordering for meta-fsl-ppc:qoriq

[Otavio Salvador]

Hello Bob,

On Wed, Feb 11, 2015 at 3:20 PM, Bob Cochran <yocto at mindchasers.com> wrote:
> For the past few months, I have patched out the way meta-fsl-ppc qoriq
> constructs MACHINEOVERRIDES because I don't see the logic in it.  It's my
> preference that the overrides I set for my specific machine (e.g., p1010rdb,
> t1040rdb, or custom-machine) are found over the default overrides in
> meta-fsl-ppc (e.g., init-ifupdown/qoriq-ppc/interfaces).
>
> By default, if I set "p1010rdb" as the MACHINE in local.conf I get:
>
> MACHINEOVERRIDES="p1010:p1010rdb:qoriq-ppc:e500v2"
>
> As you know, FILESPATH is in part built by using MACHINEOVERRIDES and the
> path is built working right to left, so a file in an e500v2 override is
> found before one under p1010rdb.
>
> Shouldn't the more specific override be to the right?
>
> I would think we want to produce the following:
>
> MACHINEOVERRIDES="e500v2:qoriq-ppc:p1010:p1010rdb"
>
> If I'm wrong, please help me to understand why.
>
> If there is agreement, then I would like to submit patches to change the
> meta-fsl-ppc conf files.

Your assumption is right. I fixed this long time ago in meta-fsl-arm:

commit 74af82332fcec03f19f278024ad131c7c6eb3f53
Author: Otavio Salvador <otavio at ossystems.com.br>
Date:   Thu Apr 11 10:06:55 2013 -0300

    Fix use of SOC_FAMILY as the most right value is preferred

    The SOC_FAMILY uses the MACHINEOVERRIDES and it evaluates from left to
    right. In this case, the most SoC specific value needs to be kept in
    the right so it take precedence.

    This has been catch when finding out why i.MX6SL EVK where using the
    wrong value as entry point, and this was the root cause.

    Signed-off-by: Otavio Salvador <otavio at ossystems.com.br>

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
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