Re: [PATCH 2/3] ARM: dts: i.MX8MP: move MAC address description to common location

[Lucas Stach <l.stach@pengutronix.de>]

Hi Ahmad,

Am Mittwoch, dem 11.01.2023 um 20:03 +0100 schrieb Ahmad Fatoum:
> Hello Lucas,
> 
> On 11.01.23 19:21, Lucas Stach wrote:
> > All i.MX8MP boards should consult the common fuse locations for the
> > MAC address of the network interfaces. Also add the second location
> > for the EQOS network interface.
> 
> Do we really want to extend use of this binding? The upstream kernel
> DT already has nvmem-cells for the MAC addresses and we have support
> for reading that out.
> 
I thought about this too, but...

>  Only thing missing is the equivalent of
> 
> Linux commit d0221a780cbc ("nvmem: imx-ocotp: add support for post processing")
> 
This isn't the only thing missing. To handle the second MAC address via
NMEM, we would need to add unaligned read/write support to the OCOTP
driver. The currently used regmap_read/write_bulk API does only work
with register aligned accesses. The benefit of NVMEM didn't look that
tempting anymore when looking at the cost of the necessary OCOTP driver
changes, so I choose to go with the more minimal change.

Regards,
Lucas

> Cheers,
> Ahmad
> 
> > 
> > Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> > ---
> >  arch/arm/dts/imx8mp-evk.dts                | 4 ----
> >  arch/arm/dts/imx8mp-tqma8mpql-mba8mpxl.dts | 4 ----
> >  arch/arm/dts/imx8mp.dtsi                   | 1 +
> >  3 files changed, 1 insertion(+), 8 deletions(-)
> > 
> > diff --git a/arch/arm/dts/imx8mp-evk.dts b/arch/arm/dts/imx8mp-evk.dts
> > index d992b14882a3..28d8c5f9292e 100644
> > --- a/arch/arm/dts/imx8mp-evk.dts
> > +++ b/arch/arm/dts/imx8mp-evk.dts
> > @@ -68,7 +68,3 @@
> >  		reg = <0xe0000 0x20000>;
> >  	};
> >  };
> > -
> > -&ocotp {
> > -	barebox,provide-mac-address = <&fec 0x640>;
> > -};
> > diff --git a/arch/arm/dts/imx8mp-tqma8mpql-mba8mpxl.dts b/arch/arm/dts/imx8mp-tqma8mpql-mba8mpxl.dts
> > index c47e7285a703..6e81f58e2786 100644
> > --- a/arch/arm/dts/imx8mp-tqma8mpql-mba8mpxl.dts
> > +++ b/arch/arm/dts/imx8mp-tqma8mpql-mba8mpxl.dts
> > @@ -53,7 +53,3 @@
> >  		reg = <0xe0000 0x20000>;
> >  	};
> >  };
> > -
> > -&ocotp {
> > -	barebox,provide-mac-address = <&fec 0x640>;
> > -};
> > diff --git a/arch/arm/dts/imx8mp.dtsi b/arch/arm/dts/imx8mp.dtsi
> > index 5da79f13d339..379fa49d6042 100644
> > --- a/arch/arm/dts/imx8mp.dtsi
> > +++ b/arch/arm/dts/imx8mp.dtsi
> > @@ -13,6 +13,7 @@
> >  feat: &ocotp {
> >  	#feature-cells = <1>;
> >  	barebox,feature-controller;
> > +	barebox,provide-mac-address = <&fec 0x640 &eqos 0x650>;
> >  };
> >  
> >  &pgc_mipi_phy1 {
>