UBI 1MiB size partition

[Angelo Dureghello]

Dear Artem,

thanks for your reply.

> UBI is a volume manager which is designed to manage the entire flash
> chip. Sometimes system designers have one or two small partitions at the
> beginning of the chip, and give the rest to UBI.
>
> You are using NAND flash, and UBI tries to reserve some amount of
> eraseblocks for bad block handling. And the count of eraseblocks to
> reserve is calculated from the entire chip size. So UBI says it wants
> 20, but reserved only 4 - all the available blocks you have. So you do
> not have any more blocks left, so you have no space.
>
> You really should re-think your design. 1MiB partition is too small,
> there are too few eraseblocks. What if one or two of them become bad?
>
Yes, i realized this. A redesign of the partition scheme is needed at this
stage.
I cannot actually change the partition scheme for some reasons connected
to the production process, but at least things are more clear now.

Regards,
Angelo