Re: [PATCH devicetree 0/3] NXP LS1028A DT changes for multiple switch CPU ports

[Michael Walle]

Am 2022-08-18 16:05, schrieb Vladimir Oltean:
> The Ethernet switch embedded within the NXP LS1028A has 2 Ethernet 
> ports
> towards the host, for local packet termination. In current device 
> trees,
> only the first port is enabled. Enabling the second port allows having 
> a
> higher termination throughput.

Is it used automatically or does the userspace has to configure 
something?

> Care has been taken that this change does not produce regressions when
> using updated device trees with old kernels that do not support 
> multiple
> DSA CPU ports. The only difference for old kernels will be the
> appearance of a new net device (for &enetc_port3) which will not be 
> very
> useful for much of anything.

Mh, I don't understand. Does it now cause regressions or not? I mean
besides that there is a new unused interface?

I was just thinking of that systemready stuff where the u-boot might
supply its (newer) device tree to an older kernel, i.e. an older debian
or similar.

-michael