[U-Boot] [PATCH 4/9] imx: nand: Place BBT patterns into free OOB region

Timo Ketola
2012-04-13T18:12:52Z

On 13.04.2012 20:19, Scott Wood wrote:
> On 04/13/2012 06:20 AM, Timo Ketola wrote:
>> First two bytes of the first OOB of erase block are reserved for factory
>> bad block marking, usually.
>>
>> Signed-off-by: Timo Ketola<timo@exertus.fi>
>> ---
>> drivers/mtd/nand/mxc_nand.c | 35 +++++++++++++++++++++++++++++++++++
>> 1 files changed, 35 insertions(+), 0 deletions(-)
>
> So what happened before? The default is at offset 8, which doesn't
> conflict with the bad block marker. It seems the actual issue is a
> conflict with ECC?

You seem to be right. I think I was badly confused with the kernel behaviour.

> And NAND_USE_FLASH_BBT wasn't defined before, so a better subject line
> for this patch would be "nand/mxc: support flash-based BBT".

Most probably right too.

> Won't veroffs = 6 conflict with ECC in the MXC_NFC_V1 case?

Seems to.

> What about 8-bit small page support, in which case the bad block marker
> is at offset 5?

What about putting into the block

#if defined(MXC_NFC_V1)
#ifndef CONFIG_SYS_NAND_LARGEPAGE

defines for pattern and version offsets and use them in bbt_*_descr
initializations? Or should they be in board configuration file?

>> +#ifdef CONFIG_SYS_NAND_USE_FLASH_BBT
>> +
>> + this->options = NAND_USE_FLASH_BBT;
>> + this->bbt_td =&bbt_main_descr;
>> + this->bbt_md =&bbt_mirror_descr;
>> +
>> +#endif
>
> Please remove those blank lines inside the ifdef.

Ok

--

Timo