Hello Charles,
On 3/5/07,
manningc2@actrix.co.nz <
manningc2@actrix.co.nz> wrote:
> This should not be the case.
> YAFFS2 writes NAND (data + tags) as a single operation. The driver should
> be performing a single write to NAND. If not then something is broken.
> With JFFS2 you still need to write the the ECC to oob, so both YAFFS and
> JFFS2 should not require a different number of commands for a nand write
> operation. The only material difference is that YAFFS needs more oob bytes
> transfered as part of the write operation.
Well, yes, your explanation seems reasonable for 2k page NAND but I
recall having the situation I've described on 312b NAND with
bitbanging controller emulation.
This however might be related to the legacy MTD/NAND version.
Anyway, I can pick up another corner case. For 2k page NAND with OOB
spread across the page, MTD/NAND layer will issue more commands for
yaffs2 than for jffs2. Though this one is just hpw MTD/NAND layer
works and not an actual yaffs2 problem.
Vitaly
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