[U-Boot-Users] Re: loading MAC address into hardware

Wolfgang Denk wd at denx.de
Sun Mar 20 17:17:26 CET 2005

In message <loom.20050319T030128-356 at post.gmane.org> you wrote:
> I think we all understand that the bootloader does not set mac address if no
> network operations have been requested, e.g. if we boot from a local flash and 
> not from a network. Now, what the question probably was:
> "I stored my mac address in u-boot environmental variable. Now I need somehow 
> set it in hardware. Is there a way to force u-boot to do it for me even though 
> it does not use network for its own needs? If that is not possible then what 

Technically it's trivial to do this. But it would be wrong to  do  it
from  the  design,  as  there  is no need for it (the Linux driver is
responsible    itself    for    sufficiently    complete     hardware

> is the best way to pass mac address to linux. I suppose then I can use ifconfig 
> to set it" 

Yes, you can use ifconfig to set the MAC address, or you can fix your
ethernet driver in Linux to initialize the hardware as needed.

There are many ways to pass  the  MAC  address:  on  current  PowerPC
systems  it's  part  of the bd_infor structure; or you can pass it as
part of the boot arguments like  some  MIPS  board  do,  or  you  can
implement bi-recs and use a bi_record for the MAC address, or ...

Or you can use the existing tools to read the environment under Linux
or ...


Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"If you can, help others. If you can't, at least don't hurt  others."
- the Dalai Lama

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