From: Arnd Bergmann <arnd@arndb.de>
To: Andrei Warkentin <andreiw@motorola.com>
Cc: linux-mmc@vger.kernel.org
Subject: Re: [comments] MMC: Reliable write support.
Date: Tue, 29 Mar 2011 09:01:31 +0200 [thread overview]
Message-ID: <201103290901.31680.arnd@arndb.de> (raw)
In-Reply-To: <AANLkTi=+LOy6V4hLsjaDd60xjEWm7jtYXaW8-4j=7TCQ@mail.gmail.com>
On Tuesday 29 March 2011, Andrei Warkentin wrote:
> On Fri, Mar 25, 2011 at 10:14 AM, Arnd Bergmann <arnd@arndb.de> wrote:
>
> I confirmed with two MMC vendors that there is no "flush". Once the
> DAT transfer completes, the data is stored on non-volatile storage as
> soon as the busy status is cleared.
>
> Reliable writes are still "more reliable" because if the DAT transfer
> is interrupted (power or reset through CMD0/CMD15 or hw pin for eMMC),
> you have predictable flash contents. So it makes sense to map REQ_FUA
> to it (and REQ_META, I would guess).
Yes, sounds good.
So I guess on MLC flash, a reliable write will go to a flash page
that does not have data in any of its paired pages.
Arnd
next prev parent reply other threads:[~2011-03-29 7:01 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-24 21:22 Reliable write support Andrei Warkentin
2011-03-24 21:22 ` [comments] MMC: " Andrei Warkentin
2011-03-25 15:14 ` Arnd Bergmann
2011-03-26 7:17 ` Andrei Warkentin
2011-03-26 7:22 ` Andrei Warkentin
2011-03-29 0:50 ` Andrei Warkentin
2011-03-29 7:01 ` Arnd Bergmann [this message]
2011-03-29 22:44 ` Andrei Warkentin
2011-03-30 12:05 ` Arnd Bergmann
2011-03-30 22:38 ` Chris Ball
2011-03-31 20:39 ` Andrei Warkentin
2011-03-31 20:58 ` Chris Ball
2011-03-31 23:40 ` [PATCH] " Andrei Warkentin
2011-04-01 0:47 ` Chris Ball
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