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Date: Wed, 9 Jan 2008 20:47:57 -0600
From: "Linas Vepstas" <linasvepstas@gmail.com>
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Subject: Re: [PATCH 1/8] pseries: phyp dump: Docmentation
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On 09/01/2008, Michael Ellerman <michael@ellerman.id.au> wrote:
>
> > > Only if you can get at rtas, but you can't get at rtas at that point.
>
> AFAICT you don't need to get at RTAS, you just need to look at the
> device tree to see if the property is present, and that is trivial.
>
> You probably just need to add a check in early_init_dt_scan_rtas() which
> sets a flag for the PHYP dump stuff, or add your own scan routine if you
> need.

I no longer remember the details. I do remember spending a lot of time
trying to figure out how to do this. I know I didn't want to write my own scan
routine; maybe that's what stopped me.  As it happens, we also did most
of the development on a broken phyp which simply did not even have
this property, no matter what, and so that may have brain-damaged me.

I went for the "most elegant" solution, where "most elegant" is defined
as "fewest lines of code", "least effort", etc.

Manish may need some hands-on help to extract this token during
early boot.  Hopefully, he'll let us know.

--linas