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Date: Mon, 25 Nov 2013 07:11:48 -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 Mon, Nov 25, 2013 at 09:29:11AM +0800, Hans Zhang wrote:
> On 2013/11/22 19:45, Ezequiel Garcia wrote:
> >> 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?
> 
> Well, yes, write through the char device would be a solution.

But, *why* are you writing through mtdblock instead?

> I think that maybe it's an optional approach through mtdblock in case we do not have
> the mtd-tools in our environments, we do provider a simpler way to write the NAND
> through mtdblock.
> 

Uh? simpler? Writing through mtdchat is as simple as it gets:

  $ cat some_file.img > /dev/mtd0

Sorry, but I'm still confused at what are you trying to accomplish.
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com