Re: Ethernet MAC address question

[Jeff Garzik <jgarzik@pobox.com>]

Don Fry wrote:
> So how does the driver distinguish between a valid, but incorrect MAC
> address, and the 'correct' MAC address?  The incorrect one that is the
> value that just happened to be in the uninitialized volatile registers,
> and the correct address which some magic platform means loaded into the
> same, but this time initialized, volatile registers.


You have to notice that certain platform-specific attributes are 
present, that tells your code to search in <this magic place> rather 
than the standard place for MAC address.

For example, some Compaqs have a magic MAC address location (this might 
even be pcnet32), and one solution proposed was looking for the 
platform's DMI table identifiers.  Another solution -- working -- was to 
load the MAC address registers when the driver loads, and just hope it 
is a correct address.

	Jeff