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Date: Fri, 20 Mar 2015 10:07:33 +0100
From: Richard Weinberger <richard@nod.at>
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To: Boris Brezillon <boris.brezillon@free-electrons.com>, =?UTF-8?B?IlFpIA==?=
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Subject: Re: detect and manage power cut on MLC NAND
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Cc: Iwo Mergler <Iwo.Mergler@netcommwireless.com>,
 "Jeff Lauruhn \(jlauruhn\)" <jlauruhn@micron.com>,
 "dedekind1@gmail.com" <dedekind1@gmail.com>,
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 =?UTF-8?B?IkZyYW5rIExpdSDliJjnvqQgKGZyYW5rbGl1KSI=?= <frankliu@micron.com>,
 "andrea.marson@dave.eu" <andrea.marson@dave.eu>,
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Am 20.03.2015 um 09:58 schrieb Boris Brezillon:
> Hi Qi,
> 
> On Fri, 20 Mar 2015 07:44:58 +0000
> Qi Wang 王起 (qiwang) <qiwang@micron.com> wrote:
> 
>>>
>>> I seem to remember a requirement to write pages to a block in a
>>> monotonic fashion (low to high). Is that still the case? It
>>> seems that the low page backup could violate that rule otherwise.
>>
>> Yes, pages need to be programmed from low to high. But it is possible
>> to skip some pages. Take a example,
>>
>> below page program ordering is ok.
>> Page 0, page 1, page 2, page 4, page 6, page 10, page 15, etc..
>> Just make sure don't turn back to program the low page is ok.
> 
> I asked a question regarding the programming sequence in answer to Iwo,
> but I'm not sure you were in Cc, so I'm asking it again.
> 
> Say page 1 is paired with page 4, can we program pages in this order:
> 1, 4, 2, 5, 3, 6, ..., so that both paired pages are programmed
> together (the Jumbo page approach Iwo described in his mail).

That's a good question. I was always told that you're not allowed
to program pages in a non-linear manner.

Thanks,
//richard