[U-Boot] [PATCH v2] fdt: rework fdt_fixup_ethernet() to use env instead of bd_t

[Kumar Gala]

On Aug 18, 2008, at 2:30 PM, Wolfgang Denk wrote:

> Dear Kumar Gala,
>
> In message <Pine.LNX. 
> 4.64.0808181422320.28491 at blarg.am.freescale.net> you wrote:
>> Move to using the environment variables 'ethaddr', 'eth1addr', etc..
>> instead of bd->bi_enetaddr, bi_enet1addr, etc.
>>
>> This makes the code a bit more flexible to the number of ethernet
>> interfaces.  Right now we assume a max of 10 interfaces.
>
> Hm... where exactly is this artificial limit coming from? Do we really
> need it?

We need some upper limit to stop checking at.

>> +		for (i = 0; i < CFG_MAX_NUM_ETH; i++) {
>> +			sprintf(enet, "ethernet%d", i);
>> +			sprintf(mac, "eth%daddr",i);
>> +
>> +			sprintf(mac, i ? "eth%daddr" : "ethaddr", i);
>> +			tmp = getenv(mac);
>
> for efficientcy, make this the first action in the loop.

done, and removed the duplicated sprintf that snuck in.

>> +			path = fdt_getprop(fdt, node, enet, NULL);
>> +
>> +			if (!path) {
>> +				debug("No alias for %s\n", enet);
>> +				continue;
>> +			}
>> +			if (!tmp) {
>> +				debug("No environment variable for %s\n", mac);
>> +				continue;
>> +			}
>
> If we assume,  that  all  existing  interfaces  must  have  addresses
> assigned, we could use a "break" here instead of the "continue". That
> would be (1) much faster on most boards and (2) would allow us to get
> rid of the artifical limit of 10.
>
> What do you think?

I dont like making this assumption and do think its too much work to  
check 10 possible aliases and skip to the next one if it doesn't exist.

- k