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From:   DENG Qingfang <dqfext@gmail.com>
To:     Ansuel Smith <ansuelsmth@gmail.com>
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        Frank Wunderlich <frank-w@public-files.de>
Subject: Re: [PATCH RFC net-next 1/3] net: dsa: allow for multiple CPU ports
Date:   Mon, 12 Apr 2021 23:30:58 +0800
Message-Id: <20210412153058.929833-1-dqfext@gmail.com>
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On Mon, Apr 12, 2021 at 06:41:58AM +0200, Ansuel Smith wrote:
> > So, drivers will read the name of every port and decide which CPU port
> > does it use?
> >
> 
> Yes, this seems to be an acceptable path to follow. The driver can
> provide a preferred CPU port or just tell DSA that every cpu is equal
> and assign them in a round-robin.
> 

So we somehow configured default CPU port in dts (by port name). In
my opinion we can just add a default CPU property in dts to specify
it (like Frank Wunderlich did earlier), and fall back to round-robin
if the property is not present, while still allow users to change it
in userspace.