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Date: Fri, 22 Nov 2013 08:45:10 -0300
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: Hans Zhang <zhanghonghui@innofidei.com>
Subject: Re: [PATCH] Make the mtdblock read/write skip the bad nand sector
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On Fri, Nov 22, 2013 at 10:10:19AM +0800, Hans Zhang wrote:
> On 2013/11/22 9:52, Ezequiel Garcia wrote:
> > On Fri, Nov 22, 2013 at 09:22:43AM +0800, Hans Zhang wrote:
> >> On 2013/11/21 18:59, Richard Genoud wrote:
> >>
> >> Here's my scenario, I want to write nand through mtdblock by dd command
> > You could get some better support by explaining why do you want to write
> > to a NAND through mtdblock. It sounds a bit ackward to me, but I'm sure
> > you have a good reason for it!
> >
> > Let's hear it :-)
> 
> Thanks for your reply.
> This is for my embed system upgrade, I reserved one nand partition for filesystem
> environment which will load to DDR while uboot booting.
> This filesystem.uboot file should be able to read both by uboot and kernel, and
> maybe written by uboot and kernel. There will be no filesystems upon the nand in
> case the loader may not support some filesystem types while uboot booting.
> 
> Seems that the trimmed environment of OS has get rid of the mtd-tools, So the dd
> command was the most convenience tools to use by hand.
> 

I still don't understand why are you using mtdblock. Why can't you write
through the char device?
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com