query: nand read/write method for 2048 + 64 byte page

Amit Kumar Sharma amitsharma.9 at samsung.com
Sat Jun 27 01:17:45 EDT 2009


Hi Vimal,

> On Friday 26 June 2009, vimal singh wrote:
>> The problem is that HW ECC engine in BCH mode dose not 
>> provide any
>> possible configuration where we can keep ECC bytes in 
>> main area
>> itself. OOB + ECC data has to be in only spare area.
>
> Healthy.  I disike that "infix OOB" myself.  It is however
> a standard ECC mode in the NAND framework.  :(
>
> So you're asking about how to map hardware-specific 
> details
> to the NAND framework?  That wasn't clear.

I think better you use some of the bytes of OOB area , In 
almoost al NAND you can read 2K page size or 4K page size 
additinal you have to read OOB or spare area of NAND.
>
>
>> Would it not be the good idea to perform read/write for 
>> full (2112 bytes) page?
>
> I'm not sure I can answer that without reading up on that
> particular NAND ECC engine.
>
> Recall however that the NAND framework will think in terms
> of 2KB reads, with OOB data on the side.  There will be
> separate reads for 2K and then 64 bytes.
>
>
>> And enable HW_ECC before read/write and then call for 
>> ecc.calculate or
>> ecc.correct accordingly. Rest all things can be taken 
>> care by
>> underlying controller driver.
I donot think when Hw_ecc is enable some software ECC 
calculation is required.
>
> Those sentences seem to elide critical parts of the 
> process.
> Like the details of OOB and ECC handling, which seem to be
> what you're not sure of...
>
>

Thanks
Amit
>
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