Re: [ECOS] Support for multiple flash types

[Grant Edwards <grante at visi dot com>]

On Wed, Nov 28, 2001 at 10:21:28AM -0700, Gary Thomas wrote:

> > It would be nice if I didn't have to roll my own flash
> > subsystem for my current project. How do other eCos users deal
> > with this problem?
> 
> Actually, this is more a question of philosophy.  eCos is
> designed to be statically configured for a particular target
> environment. We have purposely avoided dynamic configuration
> whenever possible. This was done both for size/speed of the
> resulting code, as well as simplicity of the drivers and the
> system overall.
> 
> As for the FLASH devices, it would seem rare to me that a given
> board design could tolerate massively different device choices.

I guess I'm just lucky then.  :)

I've got a couple platforms that support either Intel or AMD
style parts (and we use different sizes and multiple vendors of
"AMD" style parts).  In one case there are two footprints on
the board and either style of part may be installed.  In the
other case, it's two different versions of the board.

> I could see where it might be AMD vs Fujitsu (which are very
> similar), but not AMD vs Intel for example.

Supporting various members of the AMD "family" of devices isn't
difficult since they use the same command algorithms so all you
have to do is use the ID command to figure out the sector
layout. Unfortunately I have to support both Intel and AMD
parts.

If this isn't a common requirement, then I'll abandon the eCos
flash driver structure (which I am using in one instance) and
continue with my home made "hardware guys can't make up their
mind" style system.  Hoepfully I can write my stuff so that it
has the same API and will drop-in without requiring mods to
RedBoot et al.

-- 
Grant Edwards
grante@visi.com