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Subject: Re: [PATCH v2 4/9] powerpc/powernv: OPAL console standardise
 OPAL_BUSY loops
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org, skiboot@lists.ozlabs.org
Date: Mon, 09 Apr 2018 18:22:36 +1000
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On Mon, 2018-04-09 at 16:13 +1000, Nicholas Piggin wrote:
> We can always make exceptions to the standard form, but in those
> cases I would like to document it in the OPAL API and comment for
> the Linux side.
> 
> My thinking in this case is that it reduces time in firmware and
> in particular holding console locks. Is it likely / possible that
> we don't have enough buffering or some other issue makes it worth
> retrying so quickly?

Not sure to be honest, but yeah limiting the lock contention inside
OPAL is probably not a bad idea.

Cheers,
Ben.