[K42-discussion] SLOF/PAPR/K42

[Jimi Xenidis]

On Oct 7, 2006, at 12:38 PM, William DUCK wrote:

> Hello,
>
> I would want to know if we will be able to use SLOF to boot k42 and  
> if k42
> will use PAPR.

K42s platform code comes from Linux, it is built and linked into K42.
We do this because we were more interested in doing OS research then  
platform and device enablement.

The support for this includes G5 and pre-LPAR pSeries machines  
(Power4 systems and previous)
K42 does has been demonstrated to run on the LPAR-PAPR interfaces,  
but there is little support and has probably atrophied.

>
> Here is quote from a previous mail to one of the SLOF's developer :
>
>> Will next gen SLOF be based on PAPR?
>
> Some version might support PAPR fully.  SLOF mostly focuses on
> booting native Linux though, and if nothing else, that means we
> cannot test most of the PAPR stuff, as Linux doesn't use it.
>

IIRC, SLOF does not support the full PAPR and strives for pure OS  
IEEE-1275 conformance with some extensions that are also in the  
PAPR.  The use of rhype on SLOF should give you LPAR-PAPR, but K42 is  
not complete in that regard as mentioned above.

SLOF (on non-Cell) creates a platform that works under Linux  
CONFIG_GENERIC (aka CONFIG_MAPLE) so to get K42 to run on SLOF one  
would have to make sure that the K42-Linux module is also configured  
for this platform.

SLOF on Cell is unique because Cell is unique, the first step for K42  
on cell (regardless of FW) is to build the k42-Linux module to be  
configed for Cell, then fill in the K42 blanks as it goes, the number  
of blanks should be relatively small. The k42-linux module could be a  
serious level of effort.

-JX