booting HardHat on IBM 405GP

booting HardHat on IBM 405GP

[Zehetbauer Thomas]

Hi!

My company is going to develop an embedded solution based on a IBM 406GP
processor.
We are in early development right now and I am trying to boot linux on a
> IBM 25 EB 405 P4 WIN WAL 00
evaluation kit (this is the information on the bill of delivery).

Attempting to debug I've found linux/arch/ppc/boot/tree/main.c:start to
be the first function executed.
At the very last step this function calls
>    (*(void (*)())sa)(&board_info,
>                      initrd_start,
>                      initrd_start + initrd_size,
>                      cmdline,
>                      cmdline + strlen(cmdline));
and I can't find where execution goes on.

Any help is greatly appreciated.

TIA
Tom

PS: Does someone know how to determine the board's revision number?

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Re: booting HardHat on IBM 405GP

[Ralph Blach]

[-- Attachment #1: Type: text/plain, Size: 1151 bytes --]

Zehetbauer,

Hi,  This is a function call to sa, and if you look at the address of sa
(the starting address) I'll bet it absoulte 0.  So, what happens is you
get a jump to zero.

Heres the boot process.
1)move the ramdisk to upper memory.
2)uncompress the kernel image starting a real 0.
3)Jump to 0.

Chip Blach

Zehetbauer Thomas wrote:
>
> Hi!
>
> My company is going to develop an embedded solution based on a IBM 406GP
> processor.
> We are in early development right now and I am trying to boot linux on a
> > IBM 25 EB 405 P4 WIN WAL 00
> evaluation kit (this is the information on the bill of delivery).
>
> Attempting to debug I've found linux/arch/ppc/boot/tree/main.c:start to
> be the first function executed.
> At the very last step this function calls
> >    (*(void (*)())sa)(&board_info,
> >                      initrd_start,
> >                      initrd_start + initrd_size,
> >                      cmdline,
> >                      cmdline + strlen(cmdline));
> and I can't find where execution goes on.
>
> Any help is greatly appreciated.
>
> TIA
> Tom
>
> PS: Does someone know how to determine the board's revision number?
>

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tel;work:919-543-1207
x-mozilla-html:TRUE
url:www.ibm.com
org:IBM MicroElectronics
adr:;;3039 Cornwallis		;RTP;NC;27709;USA
version:2.1
email;internet:rcblach@raleigh.ibm.com
x-mozilla-cpt:;15936
fn:Ralph Blach
end:vcard

RE: booting HardHat on IBM 405GP

[Zehetbauer Thomas]

It seems that execution stops when calling rfi in
arch/ppc/kernel/head_4xx.S. I have put the sample code provided to
output a single character on the serial port immediately before the rfi
call and after the after the start_here label. Only the first is beeing
executed. Any ideas?

Tom

> -----Original Message-----
> From: Ralph Blach [mailto:rcblach@raleigh.ibm.com]
>
> Hi,  This is a function call to sa, and if you look at the
> address of sa
> (the starting address) I'll bet it absoulte 0.  So, what
> happens is you
> get a jump to zero.
>
> Heres the boot process.
> 1)move the ramdisk to upper memory.
> 2)uncompress the kernel image starting a real 0.
> 3)Jump to 0.
>
> Chip Blach
>
> Zehetbauer Thomas wrote:
> >
> > My company is going to develop an embedded solution based
> on a IBM 406GP
> > processor.
> > We are in early development right now and I am trying to
> boot linux on a
> > > IBM 25 EB 405 P4 WIN WAL 00
> > evaluation kit (this is the information on the bill of delivery).
> >
> > Attempting to debug I've found
> linux/arch/ppc/boot/tree/main.c:start to
> > be the first function executed.
> > At the very last step this function calls
> > >    (*(void (*)())sa)(&board_info,
> > >                      initrd_start,
> > >                      initrd_start + initrd_size,
> > >                      cmdline,
> > >                      cmdline + strlen(cmdline));
> > and I can't find where execution goes on.
> >
> > PS: Does someone know how to determine the board's revision number?

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Re: booting HardHat on IBM 405GP

[Frank Rowand]

Zehetbauer Thomas wrote:
>
> It seems that execution stops when calling rfi in
> arch/ppc/kernel/head_4xx.S. I have put the sample code provided to
> output a single character on the serial port immediately before the rfi
> call and after the after the start_here label. Only the first is beeing
> executed. Any ideas?
>
> Tom

What kernel version are you using?  Where did you get the kernel?
What is the console output, from power on to the point where it hangs?


> > Zehetbauer Thomas wrote:
> > >
> > > My company is going to develop an embedded solution based
> > on a IBM 406GP
> > > processor.
> > > We are in early development right now and I am trying to
> > boot linux on a
> > > > IBM 25 EB 405 P4 WIN WAL 00
> > > evaluation kit (this is the information on the bill of delivery).
> > >
> > > Attempting to debug I've found
> > linux/arch/ppc/boot/tree/main.c:start to
> > > be the first function executed.
> > > At the very last step this function calls
> > > >    (*(void (*)())sa)(&board_info,
> > > >                      initrd_start,
> > > >                      initrd_start + initrd_size,
> > > >                      cmdline,
> > > >                      cmdline + strlen(cmdline));
> > > and I can't find where execution goes on.
> > >
> > > PS: Does someone know how to determine the board's revision number?

Check the PVR reported by the bootrom when you power on or reset the Walnut.

405GP rev B    PVR: 40110040
405GP rev C    PVR: 40110082
405GP rev D    PVR: 401100c4


>


-Frank
--
Frank Rowand <frank_rowand@mvista.com>
MontaVista Software, Inc

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RE: booting HardHat on IBM 405GP

[Stefano Coluccini]

> It seems that execution stops when calling rfi in
> arch/ppc/kernel/head_4xx.S. I have put the sample code provided to
> output a single character on the serial port immediately before the rfi
> call and after the after the start_here label. Only the first is beeing
> executed. Any ideas?

Are you sure that the code that print a char on the serial port works also
with MMU enabled ?


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RE: booting HardHat on IBM 405GP

[Zehetbauer Thomas]

I am not certain but I have tried to enable MSR_DR and was still able to
print to the serial console.

Tom

> -----Original Message-----
> From: Stefano Coluccini [mailto:s.coluccini@caen.it]
> Sent: Wednesday, March 28, 2001 10:05 AM
> To: Zehetbauer Thomas
> Cc: linuxppc-embedded@lists.linuxppc.org
> Subject: RE: booting HardHat on IBM 405GP
>
>
>
> > It seems that execution stops when calling rfi in
> > arch/ppc/kernel/head_4xx.S. I have put the sample code provided to
> > output a single character on the serial port immediately
> before the rfi
> > call and after the after the start_here label. Only the
> first is beeing
> > executed. Any ideas?
>
> Are you sure that the code that print a char on the serial
> port works also
> with MMU enabled ?
>

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