Unmarking bad blocks?

Unmarking bad blocks?

[Andriy Korud]

Hi,
after playing with mkfs.jffs2 and nandwrite a lot of blocks on my flash chip (Samsung 128Mb) become marked as bad (and I'm sure they were not bad at the beginning).
Is it possible to 'unmark' them or should this chip is unusble anymore?
flash_eraseall gives:

nand_erase: attempt to erase a bad block at page 0x00000000
nand_erase: attempt to erase a bad block at page 0x00000040
nand_erase: attempt to erase a bad block at page 0x00000080
nand_erase: attempt to erase a bad block at page 0x000000c0
...

Even I commented out bad block checking in nand_erase(), flash_eraseall comlete successfully however blocks remain marked as bad.

Any ideas?

Thanks in advance,

--

Andriy Korud

Re: Unmarking bad blocks?

[Thomas Gleixner]

On Monday 07 June 2004 20:54, Andriy Korud wrote:
> Hi,
> after playing with mkfs.jffs2 and nandwrite a lot of blocks on my flash
> chip (Samsung 128Mb) become marked as bad (and I'm sure they were not bad
> at the beginning). Is it possible to 'unmark' them or should this chip is
> unusble anymore? flash_eraseall gives:

What does playing mean ?

> nand_erase: attempt to erase a bad block at page 0x00000000
> nand_erase: attempt to erase a bad block at page 0x00000040
> nand_erase: attempt to erase a bad block at page 0x00000080
> nand_erase: attempt to erase a bad block at page 0x000000c0
> ...

Thats odd.

> Even I commented out bad block checking in nand_erase(), flash_eraseall
> comlete successfully however blocks remain marked as bad.

Hmm, the erase command runs if you remove the bad block check in nand_erase()
inside the nand driver. So the blocks including the bad block marker should be 
erased.

NAND chip type ?
Bus width ?
Kernel version ?
MTD version ?

-- 
Thomas
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