Re: [RFC Patch net-next v2 1/8] net: ptp: add helper for one-step P2P clocks

From: <Arun.Ramadoss@microchip.com>
To: <richardcochran@gmail.com>
Cc: <andrew@lunn.ch>, <linux-kernel@vger.kernel.org>,
	<UNGLinuxDriver@microchip.com>, <vivien.didelot@gmail.com>,
	<olteanv@gmail.com>, <linux@armlinux.org.uk>,
	<Tristram.Ha@microchip.com>, <f.fainelli@gmail.com>,
	<kuba@kernel.org>, <edumazet@google.com>, <pabeni@redhat.com>,
	<netdev@vger.kernel.org>, <Woojung.Huh@microchip.com>,
	<davem@davemloft.net>
Subject: Re: [RFC Patch net-next v2 1/8] net: ptp: add helper for one-step P2P clocks
Date: Wed, 23 Nov 2022 07:10:58 +0000	[thread overview]
Message-ID: <8de1953d8297c506b58d960fc56edee135d7d8c5.camel@microchip.com> (raw)
In-Reply-To: <Y3zd4s7c3TPKd/Rb@hoboy.vegasvil.org>

Hi Richard,
Thanks for the comment.

On Tue, 2022-11-22 at 06:34 -0800, Richard Cochran wrote:
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> On Mon, Nov 21, 2022 at 09:11:43PM +0530, Arun Ramadoss wrote:
> > +/**
> > + * ptp_header_update_correction - Update PTP header's correction
> > field
> > + * @skb: packet buffer
> > + * @type: type of the packet (see ptp_classify_raw())
> > + * @hdr: ptp header
> > + * @correction: new correction value
> > + *
> > + * This updates the correction field of a PTP header and updates
> > the UDP
> > + * checksum (if UDP is used as transport). It is needed for
> > hardware capable of
> > + * one-step P2P that does not already modify the correction field
> > of Pdelay_Req
> > + * event messages on ingress.
> > + */
> 
> Does this really belong in the common PTP header?
> 
> Seems more like a driver/hardware specific workaround to me.

This patch series is extension of PTP support for KSZ9563 patch series
submitted two years back which is not mainlined.
In that patch review feedback, it was suggested to make this function
generic and so it was moved from ksz_common.h to ptp_classify.h

Link: 
https://lore.kernel.org/netdev/20201022113243.4shddtywgvpcqq6c@skbuf/

https://lore.kernel.org/netdev/20201022143429.GA9743@hoboy.vegasvil.org/

> 
> Thanks,
> Richard