[U-Boot-Users] [PATCH] lan91c96 driver MAC address detection

Wolfgang Denk wd at denx.de
Tue May 4 19:12:41 CEST 2004


In message <71555548814716479478431542AA5F8ADF8B08 at dlee2k04.ent.ti.com> you wrote:
> Actually, I added the following 2 functions to remove related
> problems... 

can you please submit a proper patch?

Your message as is is useless. I will not go and try to find  out  if
and where to add this.

> Aside from the warning you will find that if you 'directly' boot your
> system and have NOT set the mac address via the indirect bootp probe, a

Please STOP spreading this misinformation.

bootp has NOTHING to do with  setting  the  MAC  address.  I  repeat:
NOTHING.  It  has  alo  nothing  to  do  with  setting  the CPU clock
frequencies, the console baudrate, or the phase of moon.

> kernel built for a nfsroot won't make it, as the kernel driver assumes a
> valid mac is set (or available).  So, in my board's misc_init_r() I make

In this case the kernel driver is misdesigned. The old rule is that a
driver should make no assumptions about the  state  of  the  hardware
when  it  starts,  except  when  certain preconditions are well docu-
mented. But this is a  Linux  issue,  and  off  topic  here.  Go  and
complain on the Linux list if you like.

> sure to probe for a chip, if its there go ahead and set the mac address
> up.  (several boards I've used didn't have a serial eeprom).  Seems like

This is against the design principles of U-Boot.  Normally,  you  are
expected  to  initialize a device or interface if and only if you are
going to use it in U-Boot.

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
Every program has at least one bug and can be shortened by  at  least
one  instruction  --  from  which,  by induction, one can deduce that
every program can be reduced to one instruction which doesn't work.




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