Re: [PATCH v2] net: cpsw: fix obtaining mac address for am3517

[Tony Lindgren]

* Jeroen Hofstee <jhofstee@xxxxxxxxxxxxxxxxx> [161028 11:19]:
> Hello Tony,
> 
> On 28-10-16 17:52, Tony Lindgren wrote:
> > * Jeroen Hofstee <jhofstee@xxxxxxxxxxxxxxxxx> [161028 08:33]:
> > > Commit b6745f6e4e63 ("drivers: net: cpsw: davinci_emac: move reading mac
> > > id to common file") did not only move the code for an am3517, it also
> > > added the slave parameter, resulting in an invalid (all zero) mac address
> > > being returned for an am3517, since it only has a single emac and the slave
> > > parameter is pointing to the second. So simply always read the first and
> > > valid mac-address for a ti,am3517-emac.
> > And others davinci_emac.c users can have more than one. So is the
> > reason the slave parameter points to the second instance because
> > of the location in the hardware?
> 
> Sort of, the slave parameter gets determined by the fact if there is one
> or two register range(s) associated with the davinci_emac. In davinci_emac.c
> 
>     res_ctrl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>     ...
>     rc = davinci_emac_try_get_mac(pdev, res_ctrl ? 0 : 1,
>                           priv->mac_addr);
> 
> So it there are two ranges, the slave param becomes 0. It there is only one,
> it
> will be 1. Since the am3517 only has a single regs entry it ends up with
> slave 1,
> while there is only a single davinci_emac.

OK thanks for clarifying it:

Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>