Re: [PATCH v3] mtd/nand : workaround for Freescale FCM to support large-page Nand chip

On 08/18/2011 12:00 PM, Matthieu CASTET wrote:

b35362@freescale.com a =E9crit :

quoted

From: Liu Shuo <redacted>

Freescale FCM controller has a 2K size limitation of buffer RAM. In or=

der

quoted

to support the Nand flash chip whose page size is larger than 2K bytes=

,

quoted

we divide a page into multi-2K pages for MTD layer driver. In that cas=

e,

quoted

we force to set the page size to 2K bytes. We convert the page address=

 of

quoted

MTD layer driver to a real page address in flash chips and a column in=

dex

quoted

in fsl_elbc driver. We can issue any column address by UA instruction =

of

quoted

elbc controller.

Why do you need to do that ?
=20
When mtd send you a 4k page, why can't you write it by 2*2k pages write=

 ?

That would be more complicated given the statefulness of the interface,
for no real benefit.

Even better send the first 2K and then if your controller allow it send=

 the

remaining 2K without command/address phase.

IIRC Shuo tried this first and couldn't make it work.

-Scott