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Date: Fri, 28 Mar 2014 10:01:58 +0100
From: Lothar =?UTF-8?B?V2HDn21hbm4=?= <LW@KARO-electronics.de>
To: Huang Shijie <b32955@freescale.com>
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Subject: Re: [PATCHv2 1/1] mtd: gpmi: make blockmark swapping optional
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Hi,

Huang Shijie wrote:
> 于 2014年03月28日 16:16, Lothar Waßmann 写道:
> > Still there is no need for the Linux NAND driver to be able to read or
> > write partitions in a format that the Boot ROM can understand. Thus it
> If you do not use the NAND boot, there really no need to do so.
>
There is no need for the ROM code to access any other partition than
the bootloader itself. Thus Linux can perfectly well be booted from
NAND without any byte swapping.

> Since you need the NAND boot, we should enable the swapping for imx28.
>
Why? There is no need for Linux to do any swapping when not accessing
the bootloader partition.

> > is perfectly legal to allow disregarding the BB marks and solely rely on
> > a flash based BBT.
> >
> The BB mark is in the page 0 of a NAND block. But the swapping can occur 
> in _each_ page of
> a NAND block, _NOT_ only the page 0.
> 
> I think you are confusing at these two things.
> 
No, I'm not confusing anything. The swapping in any other page than
page 0 is completely useless. Thus, when there is no need to recognize
the BB markers, there in no need to do any swapping too.


Lothar Waßmann
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