From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Behun <marek.behun@nic.cz>
Subject: Re: [PATCH net-next] net: dsa: mc88e6xxx: Fix 88E6141/6341 2500mbps
 SERDES speed
Date: Sat, 6 Oct 2018 02:38:10 +0200
Message-ID: <20181006023810.20be216e@nic.cz>
References: <20181005144227.32220-1-marek.behun@nic.cz>
        <20181005212055.GA28680@lunn.ch>
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Cc: netdev <netdev@vger.kernel.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S . Miller" <davem@davemloft.net>
To: Andrew Lunn <andrew@lunn.ch>
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> Hi Marek
> 
> I'm confused.
> 
> The alt bit is used for configuring 2500. You say 2500 is only
> supported on port 5. But !port is only true for port 0?
> 
> 	  Andrew

On Topaz alt_bit is used only for port 0 for differentiating 100 mbps
vs 200 mbps. The choices for SpdValue are 0 for 10 mbps, 1 for 100
mbps or 200 mbps (if alt_bit), 2 for 1000 mbps and 3 for 2500 mbps.
2500 is allowed only on port 5. alt_bit is not used on Topaz for port
5 (serdes), therefore I used !port.

Marek