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Date: Fri, 04 May 2007 11:55:01 +0200
From: Matthieu CASTET <matthieu.castet@parrot.com>
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Subject: Re: RO jffs2 implementation for bootloader
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Hi Artem,

Artem Bityutskiy a écrit :
> On Thu, 2007-05-03 at 08:40 +0000, Matthieu CASTET wrote:
>> I need to mount a jffs2 partition in a bootloader. I tried u-boot that support
>> jffs2, but it is very slow (2 minutes for mounting a 64MB partition).
>> Do you know if there are other (fast) implemenation of jffs2 suitable for a
>> bootloader ?
> 
> Not sure about any existing "fast" implementation, but mounting a JFFS2
> partition is about scanning whole partition. You may optimize some
> thing, but you have to scan anyway.
> 
Well u-boot implementation is very slow. For 64MB partition : 2 minutes 
for u-boot and 11 s for linux (3s with summary).


>> I want to avoid to use raw partition on NAND :
>> - because the bootloader need to access several files (kernel, boot data, rescue
>> images, some configuration).
>> - nand scrubbing (on read) is not possible to handle (jffs2 don't handle it
>> either if it is a read only partition)
> 
> I would suggest to create a small JFFS2 partition with kernel so that it
> is mounted quickly by the bootloader. Then you could mount it to /boot
> of your "main" partition.
> 
Even with small partition, u-boot implementation is very slow, that's 
why I asks for other implementations.


While I am at it, is there some code of UBI (RO static partition) suited 
for integration in bootloaders ?


Thanks,

Matthieu