Re: [SPAM] FAT on NAND

[Thomas Gleixner <tglx@linutronix.de>]

On Monday 07 April 2003 05:32, Jim Zeus wrote:
> > For what ? Why don't you use JFFS2 or YAFFS, which handle NAND out of the
> > box ?
> Because I've got to build a FS which can be accessed by Windows and Linux
> at the same time.I think JFFS2/YAFFS can't be recognized by Windows
> nowadays. And , it seems like I have to support some device layer between
> the FS and Flash so the Linux can access it, isn't it?
> Is there anyway else I can choose?
No, but AFAIK is there a Windows driver for YAFFS. 
 
> Are all the functions supported by JFFS2/YAFFS? Somebody told me the wear
> levelling is supported by MTD
Crap, MTD just provides the low level interface. Bad block management, wear 
levelling and journalling must be done in the fs driver.

> Does the SMART-Media-FAT build directly on a _bare_ NAND Flash ? 
> If it is, That's nothing useful to me 'cause Linux cant access it.
You can build it on bare FLASH: But that's not the correct way for LINUX. Your 
have to build a filesystem driver, which acts on top of MTD.

1. fs-driver 
2. MTD-block-device-driver
3. MTD-partition-driver
4. Generic NAND-driver
5. yourHardwareInterface-driver

2, 3 and 4 exist.
5 is easy to build (copy an existing one and modify it to fit your hardware)

1 has to be written from scratch. 
The specifications of SmartMedia-FAT are available from
http://www.ssfdc.or.jp/english/index.htm


-- 
Thomas
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