[U-Boot-Users] ether mac auto override.

Woodruff, Richard r-woodruff2 at ti.com
Wed Jun 18 18:21:31 CEST 2003

Yes.  I've read that and inspected many of the drivers and I've yet to find
one which implements the whole specification, especially as it relates to
validating the mac address.  Is there a good example which you can point to?
I did take a few looks into the kernel/drivers/net sources and no good
examples jumped out.

The 91c111 can run with our with out an eeprom.  Just because you have an
eeprom there is no guarantee the mac is correct, just like there is nothing
which say the user inputted it correctly.  I recall working with some code
in the past which did some validation of the mac, but I am unable to find it
(not broadcast, not multicast, not 0, ...).  The closest thing to validation
a couple of the drivers do is a checksum over the eeprom this gives you some
confidence but its not a validation.

Its sort of picky to worry about it at this level, but it would be nice to
find something good.  I'll likely end up throwing in a simple check,
followed by setting the local address to what the env asked for or ... If
none, what in the rom, if none, the default which is there already.


Richard W.

> -----Original Message-----
> From: Wolfgang Denk [mailto:wd at denx.de] 
> Sent: Wednesday, June 18, 2003 2:56 AM
> To: Woodruff, Richard
> Cc: u-boot-users at lists.sourceforge.net
> Subject: Re: [U-Boot-Users] ether mac auto override. 
> Dear Richard,
> in message 
> <FD2AC9A020DDD51194710008C7089B20053D4C87 at dlee17.itg.ti.com> 
> you wrote:
> > 
> > Should u-boot define a standard way to override the mac 
> address that 
> > an ethernet chip will use (if that chip allows it)?  Back when I 
> > enabled the
> There is already such a definition.
> See the 3rd and following paragraphs in section "Note  for  
> Redundant Ethernet  Interfaces"  in  the  README (Text 
> starting "If the network interface stores some valid MAC address...").
> > 91c111 for my board, it took a couple of looks to notice that the 
> > ethaddr environment variable was not used by the 
> driver...but it was 
> > for things like
> Then the driver should be fixed.
> Best regards,
> Wolfgang Denk
> -- 
> Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
> Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: 
> wd at denx.de Murder is contrary to the laws of man and God.
> 	-- M-5 Computer, "The Ultimate Computer", stardate 4731.3

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