[U-Boot-Users] MAC address question...

[Wolfgang Denk]

In message <20040826171027.GA2759 at umax645sx> you wrote:
>
> > No. For U-Boot the reference is always the  value  of  the  "ethaddr"
> > envrionment variable.
> 
> Ah, I probably didn't explain it too well :( "ethaddr" envrionment
> variable still exist, but it's not stored together with other variables,
> but in smc's eeprom itself (so it's not stored in two different places)

This is not acceptable.  The  environment  is  defined  as  a  single
contiguous  area  in memory (RAM while U-Boot is running). I will not
accept exceptions from that rule.

> That feature is configurable (eeprom is optional and smc can be told not
> to use it). Are you interested in patch?

No, see above.

Again: there is no need for such a behaviour. If there is a valid MAC
address somewhere else, you can simply  omit  the  "ethaddr"  in  the
initialization  of  the  environment,  and  you  may even add code to
automatically bootstrap the definition from  this  external  storage.
But that's all.

> My point is exactly the same. After board is manufactured, it is put
> into automatic tester which writes mac address (basicaly it is computer
> hooked to serial line and some other signals for diagnostic) by issuing
> setenv ethaddr command. This command stores mac address directly into
> eeprom, not into the same space as other variables are stored (NOR
> flash)

No. Make your teste write it directly to the EEPROM if you like  (but
not  though  the "setenv" command, as this will always write to _one_
device only).

> Once set, overwriting mac address is allowed, but it is password protected.
> That way unexperienced user is not able to change it, but service
> technician is.

Such password protection  is  overkill.  Shall  I  show  you  how  an
unexperienced user is able to overwrite the whole environment even if
you  password protect it? You just need to read the documentation and
add 2 and 2 together.


Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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