Re: [PATCHv2 1/2] mtd: nand: Extend NAND flash detection to new MLC chips

[Matthieu CASTET <matthieu.castet@parrot.com>]

Hi,

Kevin Cernekee a écrit :
> Some of the newer MLC devices have a 6-byte ID sequence in which
> several field definitions differ from older chips in a manner that is
> not backward compatible.  For instance:
> 
Doesn't these nand support ONFI "Read Parameter Page" (cmd 0xec) ?
If yes it will be a more generic way to detect new nand features.


Matthieu




> Samsung K9GAG08U0M (5-byte sequence): ec d5 14 b6 74
> 4th byte, bits 1:0 encode the page size: 0=1KiB, 1=2KiB, 2=4KiB, 3=8KiB
> 4th byte, bits 5:4 encode the block size: 0=64KiB, 1=128KiB, ...
> 4th byte, bit 6 encodes the OOB size: 0=8B/512B, 1=16B/512B
> 
> Samsung K9GAG08U0D (6-byte sequence): ec d5 94 29 34 41
> 4th byte, bits 1:0 encode the page size: 0=2KiB, 1=4KiB, 3=8KiB, 4=rsvd
> 4th byte, bits 7;5:4 encode the block size: 0=128KiB, 1=256KiB, ...
> 4th byte, bits 6;3:2 encode the OOB size: 1=128B/page, 2=218B/page
> 
> This patch uses the new 6-byte scheme if the following conditions are
> all true:
> 
> 1) The ID code wraps around after exactly 6 bytes
> 
> 2) Manufacturer is Samsung
> 
> 3) 6th byte is zero
> 
> The patch also extends the maximum OOB size from 128B to 256B.
>