From: Christian Eggers <ceggers@arri.de>
To: Vladimir Oltean <olteanv@gmail.com>
Cc: Richard Cochran <richardcochran@gmail.com>,
Florian Fainelli <f.fainelli@gmail.com>,
Andrew Lunn <andrew@lunn.ch>,
Vivien Didelot <vivien.didelot@gmail.com>,
Jakub Kicinski <kuba@kernel.org>,
Rob Herring <robh+dt@kernel.org>,
Helmut Grohne <helmut.grohne@intenta.de>,
Paul Barker <pbarker@konsulko.com>,
Codrin Ciubotariu <codrin.ciubotariu@microchip.com>,
George McCollister <george.mccollister@gmail.com>,
Marek Vasut <marex@denx.de>,
Tristram Ha <Tristram.Ha@microchip.com>,
"David S . Miller" <davem@davemloft.net>,
Woojung Huh <woojung.huh@microchip.com>,
"Microchip Linux Driver Support" <UNGLinuxDriver@microchip.com>,
<netdev@vger.kernel.org>, <devicetree@vger.kernel.org>,
<linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH net-next 7/9] net: dsa: microchip: ksz9477: add hardware time stamping support
Date: Thu, 12 Nov 2020 16:28:44 +0100 [thread overview]
Message-ID: <2477133.fPTnnZM2lx@n95hx1g2> (raw)
In-Reply-To: <20201110193245.uwsmrqzio5hco7fb@skbuf>
Hi Vladimir,
On Tuesday, 10 November 2020, 20:32:45 CET, Vladimir Oltean wrote:
> But something is still wrong if you need to special-case the negative
> correctionField, it looks like the arithmetic is not done on the correct
> number of bits, either by the driver or by the hardware.
I got it! The problem was caused because I subtracted the "full" timestamp
(reconstructed 64 bit seconds) from the correction field. When the KSZ updates
the correction field of the PDelay_Resp message on tx, only the "partial" (2
bit seconds) egress time stamp will be added. So the invalid values in the
correction field were caused because much more seconds were subtracted on rx
than added on tx.
> And zeroing out the correctionField of the Pdelay_Resp on transmission,
> to put that value into t_Tail_Tag? How can you squeeze a 48-bit value
> into a 32-bit value without truncation?
The answer is simple: Only the lower 32 bit (tail tag) must be subtracted as
only 32 bit will be added on egress.
v2 is on the way...
regards
Christian
next prev parent reply other threads:[~2020-11-12 15:30 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-19 17:24 [RFC PATCH 0/9] net: dsa: microchip: PTP support for KSZ956x Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 1/9] dt-bindings: net: dsa: convert ksz bindings document to yaml Christian Eggers
2020-10-21 6:52 ` Kurt Kanzenbach
2020-10-21 8:46 ` Christian Eggers
2020-10-22 0:16 ` Vladimir Oltean
2020-10-22 0:40 ` Florian Fainelli
2020-10-22 10:54 ` Kurt Kanzenbach
2020-10-22 12:37 ` Vladimir Oltean
2020-10-22 19:17 ` Florian Fainelli
2020-10-26 13:54 ` Rob Herring
2020-10-19 17:24 ` [RFC PATCH net-next 2/9] net: dsa: microchip: split ksz_common.h Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 3/9] net: dsa: microchip: rename ksz9477.c to ksz9477_main.o Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 4/9] dt-bindings: net: dsa: microchip,ksz: add interrupt property Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 5/9] net: dsa: microchip: ksz9477: basic interrupt support Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 6/9] net: dsa: microchip: ksz9477: add Posix clock support for chip PTP clock Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 7/9] net: dsa: microchip: ksz9477: add hardware time stamping support Christian Eggers
2020-10-20 0:10 ` Vladimir Oltean
2020-10-20 8:39 ` Christian Eggers
2020-10-21 23:39 ` Vladimir Oltean
2020-10-22 2:42 ` Richard Cochran
2020-10-22 7:30 ` Christian Eggers
2020-10-22 10:17 ` Christian Eggers
2020-10-30 18:24 ` Vladimir Oltean
2020-11-01 9:35 ` Christian Eggers
2020-11-01 11:10 ` Vladimir Oltean
2020-11-01 22:14 ` Christian Eggers
2020-11-01 23:41 ` Vladimir Oltean
2020-11-01 23:55 ` Vladimir Oltean
2020-11-02 10:35 ` Christian Eggers
2020-11-02 12:28 ` Vladimir Oltean
2020-10-22 3:02 ` Richard Cochran
2020-10-22 9:01 ` Vladimir Oltean
2020-10-22 10:50 ` Vladimir Oltean
2020-10-22 11:11 ` Christian Eggers
2020-10-22 11:32 ` Vladimir Oltean
2020-10-22 14:34 ` Richard Cochran
2020-11-05 20:18 ` Christian Eggers
2020-11-10 1:42 ` Vladimir Oltean
2020-11-10 14:36 ` Christian Eggers
2020-11-10 16:40 ` Vladimir Oltean
2020-11-10 19:32 ` Vladimir Oltean
2020-11-11 21:49 ` Christian Eggers
2020-11-11 21:50 ` Christian Eggers
2020-11-12 15:28 ` Christian Eggers [this message]
2020-11-12 15:38 ` Vladimir Oltean
2020-11-17 11:27 ` Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 8/9] net: dsa: microchip: ksz9477: add Pulse Per Second (PPS) support Christian Eggers
2020-10-19 17:46 ` Vladimir Oltean
2020-10-20 8:38 ` Christian Eggers
2020-10-19 17:24 ` [RFC PATCH net-next 9/9] net: dsa: microchip: ksz9477: add periodic output support Christian Eggers
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=2477133.fPTnnZM2lx@n95hx1g2 \
--to=ceggers@arri.de \
--cc=Tristram.Ha@microchip.com \
--cc=UNGLinuxDriver@microchip.com \
--cc=andrew@lunn.ch \
--cc=codrin.ciubotariu@microchip.com \
--cc=davem@davemloft.net \
--cc=devicetree@vger.kernel.org \
--cc=f.fainelli@gmail.com \
--cc=george.mccollister@gmail.com \
--cc=helmut.grohne@intenta.de \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marex@denx.de \
--cc=netdev@vger.kernel.org \
--cc=olteanv@gmail.com \
--cc=pbarker@konsulko.com \
--cc=richardcochran@gmail.com \
--cc=robh+dt@kernel.org \
--cc=vivien.didelot@gmail.com \
--cc=woojung.huh@microchip.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).