[PATCH] physmap-concat map platform driver

Anton Vorontsov cbou at mail.ru
Thu May 31 17:58:38 EDT 2007


On Thu, May 31, 2007 at 11:27:49PM +0200, Lennert Buytenhek wrote:
> On Sat, May 26, 2007 at 04:29:25AM +0400, Anton Vorontsov wrote:
> 
> > This is physmap-concat driver, which is plain sa1100-flash.c
> > with factored out arch-specific code. This driver is essential for
> > boards using multiple nonindentical chips on the board.
> 
> Doesn't physmap also support multiple nonidentical chips?

Nope. E.g. if I have two chips, 32M + 16M, second chip will be visible
as 32M, which is wrong. As "workaround" I can register two physmap
devices for each chip. But then I can't concat them, i.e. use two
chips for one partition.

> What physmap doesn't support is multiple discontiguous memory
> regions.

Yes, this is another disadvantage of current physmap.

> Maybe it makes more sense to add that support to physmap
> instead?

Well.. more easier solution would be merging physmap-concat to physmap,
trying make physmap-concat platform_data-compatible.

I can try implement that.

Thanks,

-- 
Anton Vorontsov
email: cbou at mail.ru
backup email: ya-cbou at yandex.ru
irc://irc.freenode.org/bd2




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