[U-Boot] [PATCH] ne2000: take MAC address from config if available

[Daniel Mack <daniel@caiaq.de>]

Hi Wolfgang,

On Sun, Dec 14, 2008 at 12:12:24PM +0100, Wolfgang Denk wrote:
> > This adds CONFIG_NE2000_NOPROM. If set, the ethernet MAC address is taken
> > from the environment variable 'ethaddr' and the NIC is configured
> > accordingly. Needed for boards that don't have an EEPROM to store this
> > setting permanently.
> > 
> > Signed-off-by: Daniel Mack <daniel@caiaq.de>
> > 
> > ---
> >  ne2000_base.c |   38 ++++++++++++++++++++++++++++----------
> >   1 file changed, 28 insertions(+), 10 deletions(-)
> 
> Why do we need a special CONFIG_ option? is it not possible to detect
> (by software) that there is no EEPROM available, and auto-adjust?

Hmm, what's bad about a special config variable? I agree that in
general, auto-probing is a good thing, but in U-Boot with its per-board
configuration file concept, I don't see much advantage. It is very
unlikely that a certain board is produced with and without an EEPROM.

> Note that there is existing policy how to handle the  situation  that
> we have both a MAC address stored in some other storeage (like EEPROM
> on  the  NIC)  and  in  the  "ethaddr"  environment variable (see for
> example drivers/net/cs8900.c). In the end, the code shall always only
> rely on the U-Boot environment settings.

I can send a new version of this patch following this, but I wonder
why such a logic has to be implemented in the ethernet drivers and did
not find a well-defined place in some kind of layer all drivers make use
of? Wouldn't it make more sense to put some effort in this direction?

Best regards,
Daniel