[yocto] Porting of specific Kernel/Driver into yocto.

[Om Prakash PAL]

-----Original Message-----
From: Bruce Ashfield [mailto:bruce.ashfield at gmail.com] 
Sent: Monday, April 09, 2012 11:04 PM
To: Om Prakash PAL
Cc: yocto at yoctoproject.org
Subject: Re: [yocto] Porting of specific Kernel/Driver into yocto.

On Mon, Apr 9, 2012 at 12:31 PM, Om Prakash PAL
<omprakash.pal at stericsson.com> wrote:
> Hi Bruce,
> Thanks for you help.
> As you have mentioned, its working properly.
> I want to know that is there any better way of doing same thing for my scenario ?:
> here is my scenario:
> We have development branch where we write/modify our kernel/driver code i.e. thats our local kernel repository(git rep)
> and lots of driver/files being modified everyday-->so I have to take the same effect into yocto kernel also----> so except  creating patches for all modified drivers and creating .bbappend files, is there any better way of doing same thing .

Aha. Missed that.

Just create a simple recipe that points at your git repository in the SRC_URI.
If all the changes are in the tree, and you have a defconfig and you
are building
the master branch. Then pretty much everything you need can be specified in
the SRC_URI .. and that's the entire recipe.


	@Bruce, I want to add kernel dir path into SRC_URI, how can we add it ? i.e. lets imagine that my kernel is located in dir /local/kernel/*
	How we can add this kernel into SRC_URI?.(imagine that we don't have git:// and http: path, we have just dir where my kernel is located)


If you look in oe-classic, meta-ti or any one of a number of other
layers, you'll
find recipes that do just that.

The meta-kernel-dev (in the poky extras) layer has an example of using the
kernel.org tree with the yocto kern tools, and once yocto 1.3 opens up for
submissions, I have a set of changes prep'd that make it relatively simple to
use the yocto kern tools against different types of repository.

So the summary is: Depending on the type of tooling you need, and what baseline
you need for your work .. there are a number of ways to do things.

>
> Is there anyway that  instead of using yocto-kernel tree,  can we use our local kernel-tree for building images?. (should  I create separate BSP ?)

You should definitely create a BSP, that way you can tune the system specific
to your board,
	we want to create BSP for our board that is based on arm-cortex-A9 but we don't have meta/conf/machine/include/tune-armcortexa9.inc file.
	How can we create it?. 
Cheers,

Bruce

>
> Thanks in advance.
> Best Regards,
> Om Prakash Pal
> ________________________________________
> From: Bruce Ashfield [bruce.ashfield at windriver.com]
> Sent: Monday, April 09, 2012 9:32 AM
> To: Om Prakash PAL
> Cc: yocto at yoctoproject.org
> Subject: Re: [yocto] Porting of specific Kernel/Driver into yocto.
>
> On 12-04-08 10:04 AM, Om Prakash PAL wrote:
>> Hi Bruce,
>> Thanks for your reply.
>> I am totally new to Yocto.
>> I have gone through the section BSP/Linux kernel configuration and if I am not wrong then it explains how can we configure the kernel, not the how we can add/replace a  component(driver etc).
>> lets take the example of UART driver, I want to add my own UART driver code.
>> Should I write a separate recipe file (.bb) for UART Driver?.
>> if yes then I have to write the recipe files for all my drivers that will be very time consuming.
>> Is there any other way that I can port all my desired drivers into Yocto kernel?.
>
> No recipes are required per-driver, unless you are building them all
> as out of tree modules.
>
> The typical way this is done is to simply work in the extracted linux
> src tree (build/tmp/work/<your board>/linux-yocto-<hashes>/linux), manually
> patch, or copy your drivers into the tree. At this point, you'll port
> the drivers, doing test builds (bitbake -f -c compile linux-yocto) to
> ensure that your port is working. When you've completed the build phase,
> boot tests would be in order. (Do not do a 'clean' or you'll lose in
> progress changes).
>
> When you are happy with the changes, the directory where you were working
> is with the kernel git repository. So you can simply commit your
> changes, and generate patches.
>
>    git format-patch -o <your directory> HEAD^ (or however many commits
> you have)
>
> Take those patches, create a layer with a bbappend and add them like
> any other patch to any package. They'll be applied to subsequent builds
> of the kernel.
>
> I'm skipping a lot of detail there, but it is all found in the various
> manuals, and I don't want to repeat it here.
>
> Cheers,
>
> Bruce
>
>> Please help me.
>> Thanks a lot in advance.
>>
>> Best Regards,
>> Om Prakash Pal
>> ________________________________________
>> From: Bruce Ashfield [bruce.ashfield at windriver.com]
>> Sent: Wednesday, April 04, 2012 6:17 PM
>> To: Om Prakash PAL
>> Cc: yocto at yoctoproject.org
>> Subject: Re: [yocto] Porting of specific Kernel/Driver into yocto.
>>
>> On 12-04-04 04:46 AM, Om Prakash PAL wrote:
>>> Hi,
>>> I want to build my local kernel/Driver code, not the default one.
>>> please help how can i do it ?.
>>> any wiki/docs on this?.
>>
>> The BSP developer guides show how to extend the yocto kernels, and
>> also have sections on custom/different kernel versions. Have you
>> seen that doc yet ? Or have you seen it, and have specific questions ?
>>
>> Bruce
>>
>>>
>>> Best Regards,
>>> Om Prakash Pal
>>> _______________________________________________
>>> yocto mailing list
>>> yocto at yoctoproject.org
>>> https://lists.yoctoproject.org/listinfo/yocto
>>
>
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> yocto at yoctoproject.org
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