[U-Boot-Users] What's the status on erasing a nand flash with bad blocks?

[Stefan Roese]

Hi Mitsy,

On Thursday 05 October 2006 17:04, mitsy wrote:
> There was a discussion on how to handle the bad blocks when erasing
> entire nand flash few month ago. I was curious to know what you all
> decided on how to handle the issue.
>
> Now I got a nand flash (Samsung) with 2 bad blocks and I can erase and
> program it from kernel using flash_eraseall and nandwrite just fine.
> However, from u-boot (I'm using a newer nand driver, btw) the erase
> stops at the first bad block, as you know.
>
> I'm little hesitant to just fix the code to skip the bad blocks during
> erase/write since like it was discussed on the earlier thread,
> kernel's mtd driver do it that way as well...
>
> Any comments/update on this issue will be very helpful!

When I remember correctly, Wolfgang was a little hesitantly to accept any 
changes to this code, because it was taken directly from the Linux MTD code. 
But as Ladislav Michl (the original comitter of the new NAND code) stated, 
this is because the erase is normally done from the mtd-utils package:

http://article.gmane.org/gmane.comp.boot-loaders.u-boot/23621

I would suggest that we change the current U-Boot code, so that erasing 
doesn't stop at bad blocks anymore, but skips them and prints a message, like 
the linux flash_eraseall utility:

"Skipping bad block at 0x%08x"

Wolfgang: Would this be ok for you?

Mitsy: Are you willing to create a patch for this?

Best regards,
Stefan