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Date: Wed, 18 Apr 2012 15:52:19 +0800
From: Huang Shijie <b32955@freescale.com>
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To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH] mtd : add parsing code for one kind of Hynix's nand chip
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Cc: linux-mtd@lists.infradead.org, Huang Shijie <shijie8@gmail.com>,
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=E4=BA=8E 2012=E5=B9=B404=E6=9C=8818=E6=97=A5 13:00, Brian Norris =E5=86=99=
=E9=81=93:
> Now that I've given them all a second read, it really looks like this
> new Hynix chip actually follows no discernible pattern, which seems to
> suggest that we have to know all the chip parameters in order to know
> which ID decode table to use...but if we know all the parameters, then
> why do we need the table?? (Just being devil's advocate) If I had
This makes me confused too.
It looks like hardcode when i use the 0xd7 to disdinguish this nand chip.

> samples of all the chips, perhaps I could test some to determine other
> patterns, like ID wraparound behavior, but I doubt it...
>
> So really, I'd be interested in asking Hynix (and Toshiba and probably
> Samsung, for that matter): what do you expect software developers to
> do when you provide datasheets with useless ID decode tables? Are we
> supposed to read your mind to determine which chips are supposed to
> follow a given decode table?
>
> But seriously: let me know if you have better insight into how to
> associate this table with a set of chip IDs. Otherwise, I might as
I only have the H27UBG8T2A nand chip in my hand, and test it in the=20
imx28 board.
I do not have other nand chips which may also follow the same parsing=20
code as the H27UBG8T2A.


Best Regards
Huang Shijie

> well finish adding an 8-byte ID table and adding this one chip
> manually.