All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sergey Organov <sorganov@gmail.com>
To: Richard Cochran <richardcochran@gmail.com>
Cc: Vladimir Oltean <olteanv@gmail.com>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	Fugang Duan <fugang.duan@nxp.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>
Subject: Re: [PATCH  3/5] net: fec: initialize clock with 0 rather than current kernel time
Date: Wed, 08 Jul 2020 15:24:52 +0300	[thread overview]
Message-ID: <87sge2b3e3.fsf@osv.gnss.ru> (raw)
In-Reply-To: <20200708110444.GD9080@hoboy> (Richard Cochran's message of "Wed, 8 Jul 2020 04:04:44 -0700")

Richard Cochran <richardcochran@gmail.com> writes:

> On Mon, Jul 06, 2020 at 06:27:21PM +0300, Vladimir Oltean wrote:
>> There's no correct answer, I'm afraid. Whatever the default value of the
>> clock may be, it's bound to be confusing for some reason, _if_ the
>> reason why you're investigating it in the first place is a driver bug.
>> Also, I don't really see how your change to use Jan 1st 1970 makes it
>> any less confusing.
>
> +1
>
> For a PHC, the user of the clock must check the PTP stack's
> synchronization flags via the management interface to know the status
> of the time signal.

Sorry, but I'm looking at it from the POV of PTP stack, so I don't have
another one to check.

If PTP clock itself had some means of checking for its quality (like
last time is was synchronized, skew and offset estimations at that time,
etc.), then it'd render its initial value mostly unimportant indeed.

But even then, the original problem was that Ethernet packets were time
stamped with the wrong (different) PTP clock, and there is no any flags
or clock ID in the time stamp of Ethernet packet, so any flags attached
to PTP clock are still useless.

Thanks,
-- Sergey

  reply	other threads:[~2020-07-08 12:24 UTC|newest]

Thread overview: 66+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-06 14:26 [PATCH 0/5] net: fec: fix external PTP PHY support Sergey Organov
2020-07-06 14:26 ` [PATCH 1/5] net: fec: properly support external PTP PHY for hardware time stamping Sergey Organov
2020-07-06 15:08   ` Vladimir Oltean
2020-07-06 15:21     ` Sergey Organov
2020-07-06 15:47       ` Vladimir Oltean
2020-07-06 18:33         ` Sergey Organov
2020-07-07  7:04           ` Vladimir Oltean
2020-07-07 15:29             ` Sergey Organov
2020-07-08 11:00             ` Richard Cochran
2020-07-08 10:55           ` Richard Cochran
2020-07-06 14:26 ` [PATCH 2/5] net: fec: enable to use PPS feature without " Sergey Organov
2020-07-07  4:05   ` [EXT] " Andy Duan
2020-07-07 14:29     ` Sergey Organov
2020-07-06 14:26 ` [PATCH 3/5] net: fec: initialize clock with 0 rather than current kernel time Sergey Organov
2020-07-06 15:27   ` Vladimir Oltean
2020-07-06 18:24     ` Sergey Organov
2020-07-07  6:36       ` Vladimir Oltean
2020-07-07 16:07         ` Sergey Organov
2020-07-07 16:43           ` Vladimir Oltean
2020-07-07 17:09             ` Sergey Organov
2020-07-07 17:12               ` Vladimir Oltean
2020-07-07 17:56                 ` Sergey Organov
2020-07-08 11:15                   ` Richard Cochran
2020-07-08 12:14                     ` Sergey Organov
2020-07-08 11:11             ` Richard Cochran
2020-07-08 11:04     ` Richard Cochran
2020-07-08 12:24       ` Sergey Organov [this message]
2020-07-08 12:37       ` Sergey Organov
2020-07-08 14:48         ` Richard Cochran
2020-07-08 17:18           ` Sergey Organov
2020-07-06 14:26 ` [PATCH 4/5] net: fec: get rid of redundant code in fec_ptp_set() Sergey Organov
2020-07-07  4:08   ` [EXT] " Andy Duan
2020-07-07 14:43     ` Sergey Organov
2020-07-08  5:34       ` Andy Duan
2020-07-08  8:48         ` Sergey Organov
2020-07-08  8:57           ` Andy Duan
2020-07-08 12:26             ` Sergey Organov
2020-07-06 14:26 ` [PATCH 5/5] net: fec: replace snprintf() with strlcpy() in fec_ptp_init() Sergey Organov
2020-07-11 12:08 ` [PATCH v2 net] net: fec: fix hardware time stamping by external devices Sergey Organov
2020-07-11 23:19   ` Vladimir Oltean
2020-07-12 14:16     ` Sergey Organov
2020-07-12 14:47       ` Andrew Lunn
2020-07-12 15:01       ` Vladimir Oltean
2020-07-12 17:29         ` Sergey Organov
2020-07-12 19:33           ` Vladimir Oltean
2020-07-12 22:32             ` Sergey Organov
2020-07-12 23:15               ` Vladimir Oltean
2020-07-14 12:39                 ` Sergey Organov
2020-07-14 14:23                   ` Vladimir Oltean
2020-07-14 14:35                     ` Sergey Organov
2020-07-14 14:44                     ` Vladimir Oltean
2020-07-14 16:18                       ` Sergey Organov
2020-07-14 14:01   ` Richard Cochran
2020-07-14 14:27     ` Sergey Organov
2020-07-14 16:28 ` [PATCH v3 " Sergey Organov
2020-07-16 18:24   ` Jakub Kicinski
2020-07-16 20:38     ` Sergey Organov
2020-07-16 21:06       ` Jakub Kicinski
2020-07-16 21:18         ` Sergey Organov
2020-07-15 15:42 ` [PATCH net-next v2 0/4] net: fec: a few improvements Sergey Organov
2020-07-15 15:42   ` [PATCH net-next v2 1/4] net: fec: enable to use PPS feature without time stamping Sergey Organov
2020-07-15 15:42   ` [PATCH net-next v2 2/4] net: fec: initialize clock with 0 rather than current kernel time Sergey Organov
2020-07-15 15:42   ` [PATCH net-next v2 3/4] net: fec: get rid of redundant code in fec_ptp_set() Sergey Organov
2020-07-15 15:43   ` [PATCH net-next v2 4/4] net: fec: replace snprintf() with strlcpy() in fec_ptp_init() Sergey Organov
2020-07-16  3:00   ` [EXT] [PATCH net-next v2 0/4] net: fec: a few improvements Andy Duan
2020-07-16 18:37     ` Jakub Kicinski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87sge2b3e3.fsf@osv.gnss.ru \
    --to=sorganov@gmail.com \
    --cc=davem@davemloft.net \
    --cc=fugang.duan@nxp.com \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=olteanv@gmail.com \
    --cc=richardcochran@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.