[U-Boot] handling of bad blocks in nand

[Arno Steffen]

2010/6/25 Scott Wood <scottwood at freescale.com>:
> On 06/25/2010 05:18 AM, Arno Steffen wrote:
>>
>> 2010/6/24 Scott Wood<scottwood at freescale.com>:
>>>
>>> On 06/24/2010 01:28 AM, Arno Steffen wrote:
>>>>
>>>> does it mean in other words - I don't have to care for the bad block,
>>>> can write on the bad block address as it would be ok?
>>>
>>> You can't write directly to that block, but it can be included in a range
>>> of
>>> blocks as long as the range is large enough to hold the data blocks plus
>>> the
>>> bad blocks.
>>
>> Mhh. Think we misunderstood each other.
>> Lets asume block with 0x10.0000 is bad.
>>
>> I would guess from what you told me before that I could read/write to
>> 0x10.0000.
>> Of course this is than internally redirected, but from uboot point of
>> view I hope to
>> can do
>>
>> nand write 0x8000.0000 0x10.0000 1000
>
> It is "redirected" to the next good block after the one you're trying to
> write to.  But it is not fully transparent.  Suppose the block at 0x100000
> is bad, and the next block at 0x120000 is good.
>
> If you do the above command, it will skip the bad block and write to
> 0x120000.  But if you then do "nand write 80000000 120000 1000", you will
> overwrite what you previously wrote.
>
> -Scott
>

Ok, understood it now. Thanks a  lot.
-Arno