netdev - RE: [PATCH v2 net-next 02/14] dt-bindings: net: add nxp,netc-timer property

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Message-ID:
 <PAXPR04MB8510426F58E3065B22943D8C8851A@PAXPR04MB8510.eurprd04.prod.outlook.com>
Date: Thu, 17 Jul 2025 10:26:28 +0000
From: Wei Fang <wei.fang@....com>
To: Krzysztof Kozlowski <krzk@...nel.org>
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Subject: RE: [PATCH v2 net-next 02/14] dt-bindings: net: add nxp,netc-timer
 property

> On 17/07/2025 11:49, Wei Fang wrote:
> >>>
> >>> I do not think it is timestamper. Each ENETC has the ability to record
> >>> the sending/receiving timestamp of the packets on the Tx/Rx BD, but
> >>> the timestamp comes from the Timer. For platforms have multiple Timer
> >>
> >> Isn't this exactly what timestamper is supposed to do?
> >>
> > According to the definition, timestamper requires two parameters, one is
> > the node reference and the other is the port, and the timestamper is added
> > to the PHY node, and is used by the gerneric mdio driver. The PTP driver
> 
> 
> We do not speak about drivers.
> 
> > provides the interfaces of mii_timestamping_ctrl. So this property is to
> > provide PTP support for PHY devices.
> >
> >
> > timestamper:	provides control node reference and
> > 			the port channel within the IP core
> >
> > The "timestamper" property lives in a phy node and links a time
> > stamping channel from the controller device to that phy's MII bus.
> >
> > But for NETC, we only need the node parameter, and this property is
> > added to the MAC node.
> 
> I think we do not understand each other. I ask if this is the
> timestamper and you explain about arguments of the phandle. The
> arguments are not relevant.
> 
> What is this purpose/role/function of the timer device?

The timer device provides PHC with nanosecond resolution, so the
ptp_netc driver provides interfaces to adjust the PHC, and this PHC
is used by the ENETC device, so that the ENECT can capture the
timestamp of the packets.

> 
> What is the purpose of this new property in the binding here?
> 

This property is to allow the ENETC to find the timer device that is
physically bound to it. so that ENETC can perform PTP synchronization
with other network devices.