Subject: Re: [PATCH v1 1/2] dt-binding: ptp: add bindings document for dte
 based ptp clock
To: Richard Cochran <richardcochran@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com
References: <1497299161-6458-1-git-send-email-arun.parameswaran@broadcom.com>
 <1497299161-6458-2-git-send-email-arun.parameswaran@broadcom.com>
 <20170613050947.GA1684@localhost.localdomain>
From: Arun Parameswaran <arun.parameswaran@broadcom.com>
Message-ID: <cb008f0f-1585-653e-0b89-47478f9f4734@broadcom.com>
Date: Tue, 13 Jun 2017 10:46:36 -0700
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Hi Richard,

On 17-06-12 10:09 PM, Richard Cochran wrote:
> On Mon, Jun 12, 2017 at 01:26:00PM -0700, Arun Parameswaran wrote:
>> +Example:
>> +
>> +ptp_dte: ptp_dte@180af650 {
>> +	compatible = "brcm,ptp-dte";
>> +	reg = <0x180af650 0x10>;
>> +	status = "okay";
>> +};
> This patch set looks okay, as far as it goes, but how does one
> actually use the clock?
>
> How does one connect this node to an Ethernet MAC, for example?
In some of the SoC's, the DTE's NCO is synced in hardware with the Ethernet's
1588 Shim NCO (used for time-stamping the packets). We are working on getting
all the future SoC's synced this way (for Ethernet).

In other scenarios, we use an user-space app to perform the sync based on
time-stamps from external hardware sources like the Wi-Fi.
> Thanks,
> Richard