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From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Varun Deshpande <varun9485@gmail.com>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai] Request for support of SIOCSHWTSTAMP
Date: Fri, 1 Apr 2016 20:50:27 +0200	[thread overview]
Message-ID: <20160401185027.GI22286@hermes.click-hack.org> (raw)
In-Reply-To: <CABprWp=4Ph8wRqtXnB7AocU0MkaYax+qC0UHRkaoFt8uhnk=vg@mail.gmail.com>

On Fri, Apr 01, 2016 at 06:17:38PM +0200, Varun Deshpande wrote:
> Hello Folks,
> 
> As Xenomai-RTnet has combined, it is the solution for many hard realtime
> systems but the main feature which is missing is SIOCSHWTSTAMP.
> As i210 supports harware timestamping, it is crucial for performance
> analysis. But it is not supported by rt_igb driver as SIOCSHWTSTAMP returns
> "OPERATION NOT SUPPORTED"
> 
> I kindly request you guys to please incorporate this feature so that user
> can get hardware timestamp in cmsg header by enabling SIOCSHWTSTAMP option
> for rt_igb driver as many of the ptp, avb programs evaluation is done by
> hardware timestamp only.

Correct me if I am wrong, but to get meaningful hardware timestamps,
you need the machines to be synchronized with PTP, so, there is much
more work to get this working than just implement this ioctl. I
think we should start small, with software timestamps, as with
Xenomai low latencies, and the fact that determinism requires to not
fill the hardware queues, you should have some good precision already.

-- 
					    Gilles.
https://click-hack.org


  reply	other threads:[~2016-04-01 18:50 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-01 16:17 [Xenomai] Request for support of SIOCSHWTSTAMP Varun Deshpande
2016-04-01 18:50 ` Gilles Chanteperdrix [this message]
2016-04-01 20:09   ` Varun Deshpande

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