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Date:   Mon, 5 Aug 2019 10:29:20 -0700
From:   Richard Cochran <richardcochran@gmail.com>
To:     Hubert Feurstein <h.feurstein@gmail.com>
Cc:     Andrew Lunn <andrew@lunn.ch>, netdev <netdev@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>
Subject: Re: [PATCH net-next v2] net: dsa: mv88e6xxx: extend PTP gettime
 function to read system clock
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On Mon, Aug 05, 2019 at 07:12:40PM +0200, Hubert Feurstein wrote:
> It got improved, but you still have the unpredictable latencies caused by the
> mdio_done-completion (=> wait_for_completion_timeout) in imx_fec.

Yes, that is the important point.

Please take a look at other mmi_bus.write() implementations and see if
you can place the timestamps into the mii_bus layer.

Thanks,
Richard