[U-Boot-Users] Re: JFFS2+U-Boot writing an image that has been "SUMMARY"-patched?

[Martin Egholm Nielsen <martin@egholm-nielsen.dk>]

Hi Dave,

>>I'm considering patching my Linux kernel JFFS2 code with the "summary"
>>patch:
>>http://www.inf.u-szeged.hu/jffs2/mount.php
>>decreasing mount time severely. In short, this patch requires modifying 
>>some data in the end of each eraseblock - also in the image that should 
>>be written.

>>However, I'm planning on using u-boot to write the Linux root-fs - using 
>>"nand write.jffs2" - and was wondering whether this function 
>>(write.jffs2) actually cared about what it was writing?

> When I added the option all it did was allow skipping of bad blocks 
> (since JFFS2 blocks don't care where they are in the FLASH) and write
> the oob data properly for JFFS2. It didn't (and I think still
> doesn't) examine the JFFS2 data at all. As long as the summary data
> is location independent it should be OK.
Super, I kinda guessed that!

>> I tried writing "giberish" memory data using write.jffs2, and it 
>> didn't complain, though. But still, its name ".jffs2" indicate that
>> some knowledge of jffs2 is used? >
> I only meant it to indicate that the option is for writing jffs2
> images, so if changes or added features would break jffs2
> compatibility (and some were proposed a while ago) the changes should
> not be made to the jffs2 option, they would need a new one. >
Makes sense!

Thanks for sorting that out - I'll head for jffs2+summary now, then...

// Martin