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From: Tom Rini <trini@ti.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 2/2] am335x_evm: Update, document Falcon Mode support
Date: Fri, 5 Jul 2013 08:51:03 -0400	[thread overview]
Message-ID: <20130705125103.GI16630@bill-the-cat> (raw)
In-Reply-To: <kr38s4$ccm$1@ger.gmane.org>

On Thu, Jul 04, 2013 at 07:39:48AM +0000, Romain Izard wrote:
> Tom> +A further word of warning about using eMMC and partition tables.  When
> Tom> +working with SD cards we can get away with erasing small areas at a time,
> Tom> +however on eMMC we must keep erases aligned to eraseblocks and thus the
> Tom> +first erase we issue will erase the partition table.
> 
> Peter> Really? I thought eMMC behaved just like SD cards?
> 
> Tom> Yes, really.  We know what the erase block size is, and round our
> Tom> commands, probably because we really have to.  SD cards take care of
> Tom> things for us, for better or worse.
> 
> But why do we bother with erasing the eMMC in the first place? The erase
> commands are wholly optional, and only make sense as a TRIM mechanism,
> which is not our case as we will fill the memory as soon as it has been
> erased.
> 
> There is no problem in writing directly in the memory, even if it has
> not been erased previously. Or is it a measure to detect interrupted
> writes ?

I hadn't thought of it like that, I had been thinking of it like NAND
for some reason.  I'll update the instructions (and write a bunch of
garbage first) and re-confirm things.  Thanks!

-- 
Tom
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      reply	other threads:[~2013-07-05 12:51 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-03 20:09 [U-Boot] [PATCH 0/2] Update Falcon Mode docs Tom Rini
2013-07-03 20:09 ` [U-Boot] [PATCH 1/2] README.falcon: Note how we determine if we can boot the OS or not Tom Rini
2013-07-03 21:19   ` Peter Korsgaard
2013-07-03 20:09 ` [U-Boot] [PATCH 2/2] am335x_evm: Update, document Falcon Mode support Tom Rini
2013-07-03 21:28   ` Peter Korsgaard
2013-07-03 22:30     ` Tom Rini
2013-07-04  7:39       ` Romain Izard
2013-07-05 12:51         ` Tom Rini [this message]

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