[RFC PATCH 2/5] OMAP2+: add cpu id register to MAC address helper

[Roger Quadros]

On 03/13/2011 12:50 AM, ext Andy Green wrote:
> Introduce a generic helper function that can set a MAC address using
> data from the OMAP unqiue CPU ID register.
> 
> Signed-off-by: Andy Green <andy.green at linaro.org>
> ---
> 
>  arch/arm/mach-omap2/id.c              |   13 +++++++++++++
>  arch/arm/mach-omap2/include/mach/id.h |    1 +
>  2 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
> index 5f9086c..fc69ec5 100644
> --- a/arch/arm/mach-omap2/id.c
> +++ b/arch/arm/mach-omap2/id.c
> @@ -506,3 +506,16 @@ void __init omap2_set_globals_tap(struct omap_globals *omap2_globals)
>  	else
>  		tap_prod_id = 0x0208;
>  }
> +
> +
> +void omap2_die_id_to_mac(u8 *mac, int length)
> +{
> +	struct omap_die_id odi;
> +
> +	omap_get_die_id(&odi);
> +	memcpy(mac, &odi.id_0, length);
> +
> +	/* mark it as not multicast and outside official 80211 MAC namespace */
> +
> +	mac[0] = (mac[0] & ~1) | 2;
> +}
> diff --git a/arch/arm/mach-omap2/include/mach/id.h b/arch/arm/mach-omap2/include/mach/id.h
> index 02ed3aa..72e10eb 100644
> --- a/arch/arm/mach-omap2/include/mach/id.h
> +++ b/arch/arm/mach-omap2/include/mach/id.h
> @@ -18,5 +18,6 @@ struct omap_die_id {
>  };

so here lies the answer to my question "From where do you get the MAC" :)

Is there a guarantee that this MAC will work in all Ethernet setups?

-- 
regards,
-roger