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Subject: Re: [PATCH 9/9] powerpc: A new cache shape aux vectors
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org, Steven Munroe <munroesj@linux.vnet.ibm.com>
Date: Tue, 10 Jan 2017 09:18:43 -0600
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On Tue, 2017-01-10 at 07:15 -0600, Segher Boessenkool wrote:
> On Wed, Jan 04, 2017 at 04:15:35PM +1100, Benjamin Herrenschmidt wrote:
> > + * For all these fields, a value of 0 means that the information
> > + * is not known.
> > +     if (sets == 0)
> > +             info->assoc = 0xffff;
> > +     else
> 
> ...
> 
> Is this correct?  A fully associative cache should be encoded as sets == 1,
> if there are buggy firmwares that set it to 0 instead it should do the same
> as 1 here I think?

No, I just made a stupid mistake I think. PAPR does say sets=1 is fully
associative which makes sense. Probably a typo.

>   Or is 0xffff indicating "unknown" here...  But in that
> case the comment above says assoc should be 0 instead.

No it's me.

Cheers,
Ben.