Re: [PATCH] mtd: support for bit-reversed CFI cmd/query

["Nikita V. Youshchenko" <yoush@cs.msu.su>]

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> On Wed, 2008-02-27 at 23:48 +0300, Nikita V. Youshchenko wrote:
> >     mtd: support for bit-reversed CFI cmd/query
> >
> >     Some embedded boards have flash chips connected with reversed bit
> > order. Example for 16-bit width:
> >      chip D0 is bus D15
> >      chip D1 is bus D14
> >      ...
> >      chip D15 is bus D0
> >     It works perfectly for data access, however probing and issuing
> > CFI commands for such chips require bit reversing. This patch adds
> > support for this.
> >
> >     Signed-off-by: Nikita Youshchenko <yoush@cs.msu.su>
>
> Am I missing something, or did you only reverse the bits on 16-bit and
> 64-bit access, and not 8-bit or 32-bit?

Hmm... Looks so :(.
The board I work with has 16-bit flash, so I could not test others.

Btw, the vendor of the board confirmed that such a strange flash chip 
connection is 'an old hardware bug', however they decided to keep it in 
current and future revisions of the board 'for backward compatibility'.

Is it a good idea to support such strange cases in the official kernel?
If yes, I may send an updated patch.

Nikita

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