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Date: Thu, 2 Nov 2017 17:56:05 +0100
From: Andrew Lunn <andrew@lunn.ch>
To: David Daney <ddaney@caviumnetworks.com>
Cc: David Daney <david.daney@cavium.com>, linux-mips@linux-mips.org,
        ralf@linux-mips.org, James Hogan <james.hogan@mips.com>,
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        "Steven J. Hill" <steven.hill@cavium.com>, devicetree@vger.kernel.org,
        Carlos Munoz <cmunoz@cavium.com>
Subject: Re: [PATCH 6/7] netdev: octeon-ethernet: Add Cavium Octeon III
 support.
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> OK, now I think I understand.  Yes, the MAC can be hardwired to a switch.
> In fact, there are system designs that do exactly that.
> 
> We try to handle this case by not having a "phy-handle" property in the
> device tree.  The link to the remote device (switch IC in this case) is
> brought up on ndo_open()

O.K, so you totally ignore the Linux way of doing this and hack
together your own proprietary solution.
 
> There may be opportunities to improve how this works in the future, but the
> current code is serviceable.

It might be serviceable, but it will never get into mainline. For
mainline, you need to use DSA.

http://elixir.free-electrons.com/linux/v4.9.60/source/Documentation/networking/dsa/dsa.txt

Getting back to my original point, having these platform devices can
cause issues for DSA. Freescale FMAN has a similar architecture, and
it took a while to restructure it to make DSA work.

https://www.spinics.net/lists/netdev/msg459394.html

	Andrew