[U-Boot] [PATCH 1/2 v2] net, fec_mxc: only setup the device enetaddr with eeprom value, if ethaddr is not setup

[Ben Warren]

Hi Detlev,

On Wed, Mar 31, 2010 at 6:44 AM, Detlev Zundel <dzu at denx.de> wrote:

> Hi Ben,
>
> > Hold on a second.  This patch is wrong.  As Mike has pointed out, the
> > net library already gets the MAC address from the environment.  The
> > correct flow is:
> >
> > 1. Read from hardware in initialize() function
> > 2. Read from environment in net/eth.c after initialize()
> > 3. Give priority to the value in the environment if a conflict
> > 4. Program hardware in the device's init() function.
> >
> > If somebody wants to subvert the 'design philosophy', the right way is
> > to call eth_dev->init() in board code.
>
> This would mean that for the real problem of a missing mac address, the
> device then is initialized completely adding the autonegotation timeout
> to every bootup sequence, correct?
>
> My suggestion here is a crude hack, and definitely does more than needed.
 It has the advantage of having narrow scope (is limited to the board in
question).

> If it is, then it doesn't solve my problem in an acceptable way.  On the
> other hand a different route occured to Wolfgang and me in a lengthy
> discussion.  This will need a little broader interpretation of the
> design guidelines, but as I still cannot see any downside to this and it
> will also fix some inconsistent behaviour _that we currently have_
> ("setenv ethaddr ...", do not do any network transfer and boot linux), I
> want to follow this route.
>
> I will try to implement this in form of a patch in order to keep the
> discussion close to the effects on the code base.
>
> I'm looking forward to seeing what you come up with.  I personally don't
have a problem with adding the few ns to boot-up time that programming an
SOC's MAC would take, but dislike the piece-meal approach that's been done
so far.

> Cheers
>  Detlev
>
> regards,
Ben