[U-Boot] PATCH: bugfix for nand erase failure with bad blocks

Wolfgang Denk
2009-06-17T22:11:02Z

Dear Scott,

In message <20090617155421.GB6333@loki.buserror.net> you wrote:
> > If you want to erase an area but you want to be sure that 'size' bytes
> > were erased, you should use:
> >
> > 'nand erase off size'
>
> How would the "nand erase" command reliably distinguish between the two alternatives?

It cannot.

> What we could do is extend the "plus" semantics (which currently allow
> rounding the size up to a block boundary) so that if you have a plus sign
> before the size it is interpreted the same as read/write.

But it's not only with the "plus". I think erase should work similar
as write - if we allow write to skip bad blocks and "exceed" thenetto
size, then we must do the same for erase.

> I'm a little uneasy about changing the normal erase command from size to end
> -- it would break existing uses. Though, it would make it consistent with
> the NOR erase command. Perhaps a period where it warns but accepts anyway a
> size, if the second parameter is less than the first.

"if the second parameter is less than the first" ? Sorry, can't parse
that. What do you have in mind?

Best regards,

Wolfgang Denk

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