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Date:   Mon, 5 Aug 2019 15:20:45 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Harini Katakam <harinik@xilinx.com>
Cc:     Harini Katakam <harini.katakam@xilinx.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        David Miller <davem@davemloft.net>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Michal Simek <michal.simek@xilinx.com>,
        devicetree@vger.kernel.org
Subject: Re: [RFC PATCH 1/2] dt-bindings: net: macb: Add new property for PS
 SGMII only
Message-ID: <20190805132045.GC24275@lunn.ch>
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On Mon, Aug 05, 2019 at 11:45:05AM +0530, Harini Katakam wrote:
> Hi Andrew,
> 
> On Sun, Aug 4, 2019 at 8:26 PM Andrew Lunn <andrew@lunn.ch> wrote:
> >
> > On Wed, Jul 31, 2019 at 03:10:32PM +0530, Harini Katakam wrote:
> > > Add a new property to indicate when PS SGMII is used with NO
> > > external PHY on board.
> >
> > Hi Harini
> >
> > What exactly is you use case? Are you connecting to a Ethernet switch?
> > To an SFP cage with a copper module?
> 
> Yes, an SFP cage is the common HW target for this patch.

Hi Harini

So you have a copper PHY in the SFP cage. It will talk SGMII
signalling to your PS SGMII. When that signalling is complete i would
expect the MAC to raise an interrupt, just as if the SGMII PHY was
soldered on the board. So i don't see why you need this polling?

       Andrew