[PATCH] ARM: atags: add support for Marvell's u-boot

[Nicolas Pitre]

On Mon, 3 Jun 2013, Jason Cooper wrote:

> On Mon, Jun 03, 2013 at 03:07:45PM -0400, Nicolas Pitre wrote:
> > On Mon, 3 Jun 2013, Jason Cooper wrote:
> > 
> > > On Mon, Jun 03, 2013 at 08:30:57PM +0200, Willy Tarreau wrote:
> > > > Well, in fact u-boot sets it on the MAC used to boot from the network
> > > > if such a boot is performed, but that's all. So in practice you boot
> > > > without the MAC address anywhere but in the ATAGs. I'd be happy to
> > > > find a way to parse non-standard atags in a board-specific file but
> > > > they're lost early it seems :-(
> > > 
> > > I assume they are in the u-boot environment.  As such, the only answer
> > > may be to have user space utilities like flash-kernel parse the
> > > environment and then customize the appended DT for the specific board.
> > 
> > Or some board specific code could dig them out of the flash.  That at 
> > least would make this hack localized while keeping the common code 
> > clean.
> 
> If it comes to that, I think I would rather tell users to put the mac
> address on the commandline.

That is certainly a simple and viable option.  You can manage your 
U-Boot environment to construct the final command line from multiple 
variables so that some are kept static and some others are user 
editable.

But for the record, there is a precedent for digging MAC addresses out 
of flash memory -- see

arch/arm/mach-orion5x/tsx09-common.c:qnap_tsx09_find_mac_addr()


Nicolas