[SLOF] SLOF on JS21 (was: Re: [PATCH 1/2] Move archsupport.fs into board-qemu directory)

Thomas Huth thuth at redhat.com
Mon Jan 11 18:34:57 AEDT 2016

On 11.01.2016 02:58, Alexey Kardashevskiy wrote:
> On 01/08/2016 07:11 PM, Thomas Huth wrote:
>> Now I'm back from vacation ... but currently I don't have the
>> PowerStation with me anymore .... I'll try when I'm back at the
>> location where I left it...
> Turns out I have JS22 (Type 7998) and JS21 (Type 8844) here where I can
> try SLOF. btw are they any different from the SLOF bootability prospective?
> Also since it has been a while since I flashed those last time, can you
> please send few commands how to flash slof and how to switch sides?

SLOF only works on JS20 and JS21, since these were the PowerPC 970 based
blades. JS22 is POWER6, so SLOF won't work there.

JS21 also ships with a pHyp based firmware by default. So IIRC the
easiest way to boot SLOF there is to set up a TFTP server on another
machine, and then to boot the takeover image:

- Build SLOF with "make js2x"
- Then create the takeover image with "make -C board-js2x takeover"
- Copy clients/takeover/takeover.elf to your TFTP server and boot it

That should already be enough to test whether SLOF is basically still
working on JS21.

If you feel confident that SLOF is working really well again, you can
also try to flash it. But beware that some bugs only appear with the
flashed image since some steps are skipped in the takeover image (like
the biosemu stuff - but that's normally only applicable to the
PowerStation build anyway).

>From the (takeover) SLOF prompt, you can type:

 update-flash -f net:boot_rom.bin

... that will download boot_rom.bin from the TFTP server and flash it.
To boot the other side of the firmware flash, simply type:


To show the current flashside, type:


To reject the temporary flash side and restore the permanent image:

 update-flash -r

You should maybe also read the "FlashingSLOF.pdf" file in the topmost
directory of the sources first. It also explains how to back up the
temporary side before you flash another image over it.


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