[U-Boot] [PATCH] net, fec_mxc: use mac address stored in env before looking in eeprom

[Heiko Schocher <hs@denx.de>]

Hello Mike,

Mike Frysinger wrote:
> On Wednesday 24 March 2010 07:56:28 Heiko Schocher wrote:
>> doc/README.enetaddr prescribes, to use a mac address stored in
>> environment, before using a mac address stored in some special
>> place.
> 
> you're reading things incorrectly, or you didnt read the whole thing.  the 
> fec_mxc driver is correct today.  its initialize function seeds eth_device-
>> enetaddr with the hardware storage.  it is up to the common networking code 
> to sync the environment to eth_device before calling the driver init function 
> (which it does).  then the driver always uses eth_device->enetaddr.

Ok, but this driver initialize in fec_probe() (which gets called
through fecmxc_initialize() on uboot startup) always the fec mac
address registers with eeprom mac address. So, if uboot not uses
network interface, linux uses this mac address (and if no valid
mac address is in eeprom, linux has no valid mac address). But,
if uboot uses network, before booting linux, linux gets the
network address stored in ethaddr, because this driver sets
again in fec_init the mac address (at this point the content
from ethaddr) -> 2 different mac addresses used on this
plattform ... I think this could not be correct, and should be
fixed ...

So, if not changing something in the driver, how is this intended
to solve? (I know, it would be great to have a standard to pass
the mac address to linux on arm based plattforms, but as Detlev
wrote, such attempts failed ...)

I don;t want to make this through board specific code ...

While writing this, and realizing that this behaviour is a feature,
maybe this problem occur on other network drivers on arm plattforms
too ... hah, found one:

drivers/net/kirkwood_egiga.c

did it in the same way as drivers/net/fec_mxc.c ... Ok, it is
in line with uboot standard, but arm plattforms which booting
linux without doing network trafic under uboot tend to have
different mac addresses ...

This should be solved!

(Actual I don;t know, if arm linux prescribes something about
how to setup the mac address before it ...)

bye
Heiko
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