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Date: Fri, 23 Oct 2009 14:03:02 +0530
From: Amit Kumar Sharma <amitsharma.9@samsung.com>
Subject: Re: [PATCH v5 2/3] MTD: OneNAND: multiblock erase support
To: Adrian Hunter <adrian.hunter@nokia.com>,
	"Korhonen Mika.2 (EXT-Ardites/Oulu)" <ext-mika.2.korhonen@nokia.com>
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> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>> ext Amit Kumar Sharma wrote:
>>> Hi Mika,
>>>
>>> Do you have any use case for using multiblock erase.
>>>
>>>
>>> Thanks
>>> Amit
>>>
>> Yes, e.g. during development/loop testing we need to 
>> flash a new system on an MTD partition.
>> The (UBIFS) system could be tiny but the partition large 
>> in which case the erase time becomes even more 
>> significant.
>> Even in more usual cases of reflashing a bigger system 
>> this gives ca. 5 % speed improvement.
>>
>> Mika
>>
>
> However the API is imperfect because AFAICT OneNAND 
> multiblock erase
> does not require that the blocks are sequential i.e. any 
> 64 eraseblocks
> from the same chip can be erased together.  So we would 
> really need an
> 'erasev()' API to take complete advantage of it.
>
I feel we should have a use case for multi block erase for 
UBI wear leveling.
it is just a opinion.
Multi block erase can  be useful if implement 'erasev' api 
at file system level.

Thanks
Amit