Change Endianess for MIPS build

Change Endianess for MIPS build

[Robert Berger]

Hi,

I was wondering what needs to be done to build (at least) a little
endian qemu root file system for MIPS.

Yocto builds this:

ELF 32-bit MSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
linked (uses shared libs), not stripped

I would need this:

ELF 32-bit LSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
linked (uses shared libs), not stripped

I guess SITEINFO_ENDIANESS (endian-big, endian-little) needs to be
changed to endian-little somewhere.

Can you please point me to where this needs to be done?

... or maybe I'm completely wrong and it needs to be done elsewhere ...

Regards,

Robert

..."I'm afraid that I've seen too many people fix bugs by looking at
debugger output, and that almost inevitably leads to fixing the symptoms
rather than the underlying problems." --Linus

My public pgp key is available at:
http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x90320BF1

Re: Change Endianess for MIPS build

[Bruce Ashfield]

On 11-04-05 06:43 AM, Robert Berger wrote:
> Hi,
>
> I was wondering what needs to be done to build (at least) a little
> endian qemu root file system for MIPS.
>
> Yocto builds this:
>
> ELF 32-bit MSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
> linked (uses shared libs), not stripped
>
> I would need this:
>
> ELF 32-bit LSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
> linked (uses shared libs), not stripped
>
> I guess SITEINFO_ENDIANESS (endian-big, endian-little) needs to be
> changed to endian-little somewhere.
>
> Can you please point me to where this needs to be done?

For the kernel, you'll need to modify the configuration to
be little endian. There is latent support in the kernel tree,
and I'll see about making the switch here so I can send some
better steps/changes for the kernel.

As for the rest of the system, you'd likely also need
to modify TARGET_ARCH to be mipsle, and adjust the
compile flags as required. I'm sure that there is an
example of this, but my quick check didn't reveal it.

Hopefully others will jump in with the right pointers!

Cheers,

Bruce

>
> ... or maybe I'm completely wrong and it needs to be done elsewhere ...
>
> Regards,
>
> Robert
>
> ..."I'm afraid that I've seen too many people fix bugs by looking at
> debugger output, and that almost inevitably leads to fixing the symptoms
> rather than the underlying problems." --Linus
>
> My public pgp key is available at:
> http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x90320BF1
>
>
> _______________________________________________
> yocto mailing list
> yocto@yoctoproject.org
> https://lists.yoctoproject.org/listinfo/yocto

Re: Change Endianess for MIPS build

[Khem Raj]

On 4/5/2011 3:43 AM, Robert Berger wrote:
> Hi,
>
> I was wondering what needs to be done to build (at least) a little
> endian qemu root file system for MIPS.
>
> Yocto builds this:
>
> ELF 32-bit MSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
> linked (uses shared libs), not stripped
>
> I would need this:
>
> ELF 32-bit LSB executable, MIPS, MIPS64 version 1 (SYSV), dynamically
> linked (uses shared libs), not stripped
>
> I guess SITEINFO_ENDIANESS (endian-big, endian-little) needs to be
> changed to endian-little somewhere.
>
> Can you please point me to where this needs to be done?
>

mipsel is treated as a different machine. Its not supported (yet) in 
oe-core. Its on my todo list unless someone beats me to it. You need
to add machine support and infra support. You can look at classic 
openembedded as reference. Where it is supported.


> ... or maybe I'm completely wrong and it needs to be done elsewhere ...
>
> Regards,
>
> Robert
>
> ..."I'm afraid that I've seen too many people fix bugs by looking at
> debugger output, and that almost inevitably leads to fixing the symptoms
> rather than the underlying problems." --Linus
>
> My public pgp key is available at:
> http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x90320BF1
>
>
> _______________________________________________
> yocto mailing list
> yocto@yoctoproject.org
> https://lists.yoctoproject.org/listinfo/yocto