Setting MAC address from I2C EEPROM - debug / commands? (Xilinx)

[Sean Anderson]

On 11/23/22 10:11, Michal Simek wrote:
> 
> 
> On 11/23/22 14:27, Michael Walle wrote:
>>>> ethernet {
>>>>       nvmem-cells = <&mac_address>;
>>>>       nvmem-cell-names = "mac-address";
>>>> };
>>>>
>>>> You'll need 2022.07 for this I think. This is the same method which
>>>> Linux uses. I added this specificly to be able to load MAC addresses
>>>> from EEPROMs without needing to hard code stuff into Kconfig.
>>>
>>> This looks good and I see Sean wired it in the U-Boot already. It should work
>>> fine with all Xilinx formats but on boards just for MAC address. (FRU format is
>>> also designed in a way that the same boards have MAC address at the same location).
>>> The code I described above is also checking in FRU format that checksums are
>>> correct and also reading more information from it for other use cases.
>>
>> You might also be interested in the new NVMEM layout patch series:
>> https://lore.kernel.org/lkml/20221118185118.1190044-1-michael@walle.cc/
> 
> This is interesting. But how can you use the nvmem-cell description for mac address reading which Sean mentioned above?

Hasn't been implemented yet. I personally don't have such a layout, so
I haven't added it.

--Sean

> Also DT description is saying that you are particular format but it doesn't mean that data is correct. I see that pretty much you can in add_cells refuse to create description if CRCs fails but maybe any format autodetection would be good to have. AFAIK Xilinx is using 3 formats now where 2 are legacy and FRU which is very similar to onie-tlv.
> 
> Thanks,
> Michal
>