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RE : RE : Multiple partitions on a FLASH device.
- From: "Vincent Catros" <Vincent dot Catros at elios-informatique dot fr>
- To: "'Andrew Lunn'" <andrew at lunn dot ch>
- Cc: <ecos-discuss at sources dot redhat dot com>
- Date: Tue, 25 Nov 2003 11:59:09 +0100
- Subject: [ECOS] RE : RE : [ECOS] Multiple partitions on a FLASH device.
Andrew,
Sorry for my late answer but, as a newbye with eCos, I preferred to
"dive" a little bit more into source code before saying something
obviously wrong.
> -----Message d'origine-----
> De?: Andrew Lunn [mailto:andrew@lunn.ch]
> Envoyé?: mercredi 19 novembre 2003 11:57
> À?: Vincent Catros
> Cc?: 'Andrew Lunn'; ecos-discuss@sources.redhat.com
> Objet?: Re: RE : [ECOS] Multiple partitions on a FLASH device.
>
> > OK, this will work on a "Linux Synthetic Target" because that way we
> > create a totaly separated FLASH device.
>
> How are they seperate. I don't understand what you mean.
OK, my sentence was not clear.
I was thinking that you asked me to create 2 "Synthetic FLASH Device"
emulated by 2 different files. That was the meening of "totaly separated
FLASH devices".
I think that using 1 "Synthetic FLASH device" with 2 partitions will
work.
But this is a particular case.
With "Synthetic FLASH Driver", the "FLASH" device is emulated by a file.
Mutual access to different regions of a file (different FLASH
partitions) using different file handles are safe.
For "real FLASH device" driver I think it's different.
> > I think this is not possible without modifying the FLASH driver.
>
> What do you think is wrong with the FLASH driver. Why cannot it do
> this?
Some FLASH registers are accessed for read/write/erase operations.
Mutual accesses to tis registers don't seem to be safe.
I did'nt seen any critical ressource access protection.
So, mutual read/write/erase operations issued from 2 different JFFS2
file-system will probably go wrong at FLASH device level.
Regards
Vincent
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