[yocto] Noobie questions

[Gary Thomas]

On 2017-04-17 16:27, bahjat khan wrote:
> Hi Gary,

n.b. it's polite to keep responses on the mailing list so that everyone benefits!

>
>
> Thanks for the response!
>
>
> How will i know what to change in the local.conf file?
> Is there a Yocto article that tells me what the different variables in .bb and .conf files mean?

The Yocto (OpenEmbedded) documentation is quite thorough.
   https://www.yoctoproject.org/documentation

> ------------------------------------------------------------------------------------------------------------------------
> *From:* yocto-bounces at yoctoproject.org <yocto-bounces at yoctoproject.org> on behalf of Gary Thomas <gary at mlbassoc.com>
> *Sent:* 17 April 2017 12:59
> *To:* yocto at yoctoproject.org
> *Subject:* Re: [yocto] Noobie questions
>
> On 2017-04-16 20:23, bahjat khan wrote:
>> Hi Guys,
>>
>>
>> I'm extremely new to the yocto project, i've done quite a bit of reading on it but i'm still very confused.
>>
>> I've set my self a simple task of changing the kernel for a Yocto image that i build, the commands i use to build this
>> yocto image are:
>
> <text would have been a better choice than an image>
>   $ git clone http://git.yoctoproject.org/git/poky
>   $ cd poky
>   $ git checkout -b fido origin/fido
>   $ source oe-init-build-env
>   $bitbake core-image-minimal
>   $runqemu qemux86
>
> Check out a newer revision - fido is VERY OLD.  Probably best to use morty which is the upcoming 2.3 release
>
>>
>> |$ git clone http://git.yoctoproject.org/git/poky $ cd poky $ git checkout -b fido origin/fido $ source oe-init-build-env
>> $bitbake core-image-minimal $runqemu qemux86|
>>
>> I understand that i need to make changes to the poky.conf file to specify what kernel i want to use (i have a standard
>> choice between 3.14 and 3.19).
>
> No, make such changes in your local.conf
>
>>
>> However if i want to use a different kernel such as 4.4, i do this by making the changes in the poky.conf file, copying
>> linux-yocto_3.19.bb file and renaming it to linux-yocto_4.4.bb. I also change the SRC_URI to
>> "git://git.yoctoproject.org/linux-yocto-4.4.git;barcelone=1;branch=${KRBRANCH},${KMETA};name=machine,meta"
>>
>> It doesn't seem to find the place where it needs to download 4.4 from even though it's on the yocto website. I can
>> download it by simply typing "git clone xxxx"
>>
>> Also i haven't changed the SRCREV_machine_qemuarm ?= "xxxxxxxxxxxx" numbers, because i don't know what they are or what
>> the variable SRCREV_machine_qemuarm is.
>
> You should never need to mess with these settings.
>
>>
>> With these warnings, it reverts back to 3.19 kernel.
>>
>> I hope i've explained my problem well, but if you are still confused please let me know.
>>


-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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