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 for <linux-mtd@lists.infradead.org> from <stewart@linux.vnet.ibm.com>;
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From: Stewart Smith <stewart@linux.vnet.ibm.com>
To: Cyril Bur <cyrilbur@gmail.com>, dwmw2@infradead.org,
 computersforpeace@gmail.com, mpe@ellerman.id.au
Cc: linuxppc-dev@lists.ozlabs.org, linux-mtd@lists.infradead.org
Subject: Re: [PATCH 2/2] mtd: powernv_flash: Lock around concurrent access to
 OPAL
In-Reply-To: <20170607054355.10590-2-cyrilbur@gmail.com>
References: <20170607054355.10590-1-cyrilbur@gmail.com>
 <20170607054355.10590-2-cyrilbur@gmail.com>
Date: Tue, 18 Jul 2017 15:01:03 +1000
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Cyril Bur <cyrilbur@gmail.com> writes:
> OPAL can only manage one flash access at a time and will return an
> OPAL_BUSY error for each concurrent access to the flash. The simplest
> way to prevent this from happening is with a mutex.
>
> Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
> ---
> This is to address https://github.com/open-power/skiboot/issues/80

part of me wants to say "let's only take the lock if we ever get back
OPAL_BUSY" or something like that (have a DT property to say the flash
supports concurrent ops?)

Although the other part of me says "you're overthinking this, get back
to the work you're meant to be doing" :)

-- 
Stewart Smith
OPAL Architect, IBM.