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Date:   Wed, 22 Jul 2020 00:37:41 +1000
From:   Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v3 2/3] powerpc/powernv/idle: Rename
 pnv_first_spr_loss_level variable
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Excerpts from Pratik Sampat's message of July 21, 2020 8:29 pm:
>=20
>=20
> On 20/07/20 5:27 am, Nicholas Piggin wrote:
>> Excerpts from Pratik Rajesh Sampat's message of July 18, 2020 4:53 am:
>>> Replace the variable name from using "pnv_first_spr_loss_level" to
>>> "pnv_first_fullstate_loss_level".
>>>
>>> As pnv_first_spr_loss_level is supposed to be the earliest state that
>>> has OPAL_PM_LOSE_FULL_CONTEXT set, however as shallow states too loose
>>> SPR values, render an incorrect terminology.
>> It also doesn't lose "full" state at this loss level though. From the
>> architecture it could be called "hv state loss level", but in POWER10
>> even that is not strictly true.
>>
> Right. Just discovered that deep stop states won't loose full state
> P10 onwards.
> Would it better if we rename it as "pnv_all_spr_loss_state" instead
> so that it stays generic enough while being semantically coherent?

It doesn't lose all SPRs. It does physically, but for Linux it appears=20
at least timebase SPRs are retained and that's mostly how it's=20
documented.

Maybe there's no really good name for it, but we do call it "deep" stop=20
in other places, you could call it deep_spr_loss maybe. I don't mind too=20
much though, whatever Gautham is happy with.

Thanks,
Nick