[U-Boot] imx: Vybrid VF610 mac address issue

[Benoît Thébaudeau]

Hi Andy, Fabio,

On Wednesday, June 5, 2013 11:13:52 PM, Fabio Estevam wrote:
> Hi Andy,
> 
> On Wed, Jun 5, 2013 at 5:54 PM, Andy Voltz <andy.voltz at timesys.com> wrote:
> > I recently tried booting the VF610 support on the Tower board, but the mac
> > address is reversed in Linux userspace. DHCP/BOOTP seems to work properly
> > in u-boot.
> >
> > I'm booting this kernel:
> > https://github.com/Timesys/linux-timesys/
> > ref: 2c4ead2dd6da019f5052a69b12c8f5b6b71f8dca
> >
> > I haven't yet seen how the address is passed to the kernel, but our
> > previous
> > u-boot support does not have this issue with the same kernel. That u-boot
> > branch is also on our github.
> 
> The MAC address is read in the imx_get_mac_from_fuse() function in
> arch/arm/cpu/armv7/vf610/generic.c
> 
> Try printing all the elements of mac[] array in this function and
> check if the logic is correct there.

You probably had programmed the fuses with a MAC address on your board, and then
replaced the existing U-Boot with the mainline version. These 2 U-Boot-s may
interpret the MAC fuses in a different way. Especially, note that VF610
interprets the MAC fuses with reversed endianness compared to i.MX6 in mainline
U-Boot. This is documented in doc/README.<SoC>. There may be the same difference
between VF610 in mainline U-Boot and the other version of U-Boot that you used
first.

Best regards,
Benoît