PPC 440 System

PPC 440 System

[simon]

I have an IBM ebony development board which has a PPC 440 
processor. I am trying to build a development system for it. It 
currently loads a cross compiled kernel and kicks out messages via 
the first serial port, no vga. It mounts the root fs via nfs and tries to 
exec /sbin/init. At this point the system appears to hang. 

If I remove /sbin/init from the nfs root the kernel panics as expected, 
so I assume root is mounted ok. I have tried to build a minimum root 
filesystem which contains /dev/console, /dev/ttyS0 and a statically 
linked /sbin/init. The init just does a printf but I do not see this 
message. Does anyone know it this should work ? 

Initially I tried to build a root filesystem from files on a Mac Clone 
running Yellow Dog Linux. I believe this has a PPC 604e processor. 
Should this systems binaries/libraries run on the 440GP ?

Can I expect a statically linked executable, made on the Mac, to run
on the 440GP?


Many Thanks

Simon. 
__________________________

Simon Haynes - Baydel 
Phone : 44 (0) 1372 378811
Email : simon@baydel.com
__________________________

Re: PPC 440 System

[Roland Dreier]

    simon> If I remove /sbin/init from the nfs root the kernel panics
    simon> as expected, so I assume root is mounted ok. I have tried
    simon> to build a minimum root filesystem which contains
    simon> /dev/console, /dev/ttyS0 and a statically linked
    simon> /sbin/init. The init just does a printf but I do not see
    simon> this message. Does anyone know it this should work ?

Yes, a static /sbin/init should work.

    simon> Initially I tried to build a root filesystem from files on
    simon> a Mac Clone running Yellow Dog Linux. I believe this has a
    simon> PPC 604e processor. Should this systems binaries/libraries
    simon> run on the 440GP ?

    simon> Can I expect a statically linked executable, made on the
    simon> Mac, to run on the 440GP?

Probably not.  The 440GP has no floating point hardware, so you will
need (at least) to build a special glibc without FP instructions and
also make sure your gcc is set up not to generate FP instructions.

Your best bet is probably to download ELDK (a free Embedded Linux
Development Kit) from www.denx.de.  Dan Kegel also has some good PPC
4xx cross development information at www.kegel.com.

Best,
  Roland

Re: PPC 440 System

[Matt Mackall]

On Mon, Jul 14, 2003 at 09:16:38AM -0700, Roland Dreier wrote:
>     simon> If I remove /sbin/init from the nfs root the kernel panics
>     simon> as expected, so I assume root is mounted ok. I have tried
>     simon> to build a minimum root filesystem which contains
>     simon> /dev/console, /dev/ttyS0 and a statically linked
>     simon> /sbin/init. The init just does a printf but I do not see
>     simon> this message. Does anyone know it this should work ?
> 
> Yes, a static /sbin/init should work.
> 
>     simon> Initially I tried to build a root filesystem from files on
>     simon> a Mac Clone running Yellow Dog Linux. I believe this has a
>     simon> PPC 604e processor. Should this systems binaries/libraries
>     simon> run on the 440GP ?
> 
>     simon> Can I expect a statically linked executable, made on the
>     simon> Mac, to run on the 440GP?
> 
> Probably not.  The 440GP has no floating point hardware, so you will
> need (at least) to build a special glibc without FP instructions and
> also make sure your gcc is set up not to generate FP instructions.

You can build a 440 kernel with FPU emulation and it will run native
apps just fine, otherwise they'll core dump. I bootstrapped a full
native Debian PPC system on an Ebony board a few months ago.

-- 
Matt Mackall : http://www.selenic.com : of or relating to the moon

Re: PPC 440 System

[simon]

I don't understand. Can I not just use the math emulation in the kernel ?

Cheers

Simon.

On 14 Jul 2003 at 9:16, Roland Dreier wrote:

>     simon> If I remove /sbin/init from the nfs root the kernel panics
>     simon> as expected, so I assume root is mounted ok. I have tried
>     simon> to build a minimum root filesystem which contains
>     simon> /dev/console, /dev/ttyS0 and a statically linked
>     simon> /sbin/init. The init just does a printf but I do not see
>     simon> this message. Does anyone know it this should work ?
> 
> Yes, a static /sbin/init should work.
> 
>     simon> Initially I tried to build a root filesystem from files on
>     simon> a Mac Clone running Yellow Dog Linux. I believe this has a
>     simon> PPC 604e processor. Should this systems binaries/libraries
>     simon> run on the 440GP ?
> 
>     simon> Can I expect a statically linked executable, made on the
>     simon> Mac, to run on the 440GP?
> 
> Probably not.  The 440GP has no floating point hardware, so you will
> need (at least) to build a special glibc without FP instructions and
> also make sure your gcc is set up not to generate FP instructions.
> 
> Your best bet is probably to download ELDK (a free Embedded Linux
> Development Kit) from www.denx.de.  Dan Kegel also has some good PPC
> 4xx cross development information at www.kegel.com.
> 
> Best,
>   Roland
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

__________________________

Simon Haynes - Baydel 
Phone : 44 (0) 1372 378811
Email : simon@baydel.com
__________________________

Re: PPC 440 System

[Matt Porter]

This should have been on linuxppc-embedded.

On Tue, Jul 15, 2003 at 10:24:13AM +0100, simon@baydel.com wrote:
> I don't understand. Can I not just use the math emulation in the kernel ?

Yes you can. However, most developers on PPC4xx are interested in
eventual deployment.  Kernel math emulation is slow relative to
a soft float enabled userland so using something like ELDK or MVL
with PPC4xx/8xx makes a lot more sense.  If you want to leverage
binaries from Yellowdog/Debian/foo that are compiled for a classic
PPC processor rather than natively then you'll need to enable math
emulation.

Regards,
-- 
Matt Porter
mporter@kernel.crashing.org