NAND device: all blocks bad after restart, how to recover?

[Artem Bityutskiy]

On Wed, 2011-03-09 at 08:39 -0800, Lars Michael wrote:
> Hello,
> 
> I repost this issue, with correct subject and hope to have some
> feedback. After working with getting UBI images mounted in Linux (it did
> work for a sec!) the NAND device suddenly went totally bad after a system
> restart! So all blocks are reported bad and the mtd is no longer visible
> in Linux.

So do mtd tests work fine with your flash?

>  Before it had just a few bad blocks.

Do you have any old logs where you could find the bad block numbers?

> NAND device: Manufacturer ID: 0x2c, Chip ID: 0xca (Micron
> NAND 256MiB 3,3V 16-bit)
> Bad block table not found for chip 0
> Bad block table not found for chip 0
> Scanning device for bad blocks
> Bad eraseblock 0 at 0x000000000000
> Bad eraseblock 1 at 0x000000020000
> Bad eraseblock 2 at 0x000000040000
> Bad eraseblock 3 at 0x000000060000
> Bad eraseblock 4 at 0x000000080000
> Bad eraseblock 5 at 0x0000000a0000
> Bad eraseblock 6 at 0x0000000c0000
> <cut>
> Bad eraseblock 2046 at 0x00000ffc0000
> Bad eraseblock 2047 at 0x00000ffe0000
> No space left to write bad block table
> fsl_nfc: NAND Flash not found !
> m25p80 spi1.1: at26df081a (1024 Kbytes)
> Creating 1 MTD partitions on "Atmel at26df081a SPI Flash
> chip":
> 0x000000000000-0x000000100000 : "at26df081a"

Do you have any logs when this thing happened?

> Assuming this is a software issue, can the bbt somehow be corrupt,
> reporting all blocks bad even if they are not?

I do not know.

> Is the problem likely to be in the UBI layer or in the NAND driver
> (I suspect the first) and how can I troubleshoot this?

I might be broken driver which reports write errors, and then UBI marks
all blocks bad. We might probably need some limit in UBI to prevent
situations like this.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)