[U-Boot] ethernet: ROM MAC address vs env variable MAC address

[Lukasz Majewski <lukma@denx.de>]

Hi Prabhakar,

> Hi All, 
> 
> I am seeing following type of code for MAC address write for a
> network device.
> 
> net/eth-uclass.c  eth_post_probe()   or net/eth_legacy.c
> eth_write_hwaddr()
> 
> 	eth_env_get_enetaddr_by_index("eth", dev->seq, env_enetaddr);
> 	if (!is_zero_ethaddr(env_enetaddr)) {
> 		if (!is_zero_ethaddr(pdata->enetaddr) &&
> 		    memcmp(pdata->enetaddr, env_enetaddr, ARP_HLEN)) {
> 			printf("\nWarning: %s MAC addresses don't
> match:\n", dev->name);
> 			printf("Address in ROM is          %pM\n",
> 			       pdata->enetaddr);
> 			printf("Address in environment is  %pM\n",
> 			       env_enetaddr);
> 		}
> 
> 		/* Override the ROM MAC address */
> 		memcpy(pdata->enetaddr, env_enetaddr, ARP_HLEN);
> 
> Why ROM MAC address getting overwritten by environment env MAC
> address. MAC address is something unique and assigned to a particular
> device. So one should never change its MAC address.
> 

It may happen that company which uses NXP processor wants to use their
own set of MAC addresses.

> Please suggest. 
> 
> Regards,
> Prabhakar
> 
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> https://lists.denx.de/listinfo/u-boot



Best regards,

Lukasz Majewski

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