Re: [PATCH] mtd/nand: Support Micron chips, 4KB page

[Artem Bityutskiy <dedekind1@gmail.com>]

On Mon, 2010-07-26 at 13:04 -0700, Brian Norris wrote:
> The following parts exhibit some interesting patterns in their ID strings.
> Their ID strings are not fully compatible with the current nand_base.c
> detection algorithm. In order to detect them properly, I have taken the
> liberty to develop a heuristic algorithm. None of these chips have a *good*
> detection pattern listed in their datasheets, although MT29F16G08MAA has a
> table on p.24 of its data sheet (not included here).
> 
> Part			ID String		Block	Page	OOB
> MT29F16G08ABABA		2C 48 00 26 89 00 00	512K	4K	224
> MT29F16G08CBABA		2C 48 04 46 85 00 00	1024K	4K	224
> MT29F16G08MAA		2C D5 94 3E 74 00 00	512K	4K	218
> 
> I have attached a table logging most of the relevant data for the many chips
> I have researched. The three chips are highlighted red, although there are
> variants of the chips listed as well. I believe this patch should correctly
> identify all the 5-byte ID Micron chips.
> 
> And before the question is asked: I realize that these chips support ONFI,
> so that should be the primary means by which to identify them, but I would
> still like to be able to detect these properly without ONFI if necessary,
> especially considering some of the older NAND controllers we still use do not
> support reading ONFI data.
> 
> Feedback on my logic is appreciated.
> 
> Signed-off-by: Brian Norris <norris@broadcom.com>

Really not sure about this patch. Sounds like ONFI should be used,
except for those few chips which do not support reading ONFI data. The
heuristics you add smell fishy...
 
-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)