From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ilya Yanok <yanok@emcraft.com>
Date: Wed, 14 Dec 2011 03:46:57 +0400
Subject: [U-Boot] Request for Help: How to save data to an SD/MMC card
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Hi Graeme,

On 14.12.2011 03:37, Graeme Russ wrote:
>> Well, it shouldn't be that hard to get the data written to specific
>> blocks on the dev PC using dd command.
> 
> But what about bad blocks?

You don't need to worry much about this. MMC/SD card are not a raw flash
devices they contain FTL that handles this internally. See
http://www.linux-mtd.infradead.org/doc/ubifs.html#L_raw_vs_ftl
for details.

That's why you can use generic filesystems on MMC/SD (neither FAT not
EXT2/3/4 is not designed for raw flash).

Regards, Ilya.