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Date:   Fri, 09 Dec 2022 15:23:51 +0100
From:   Michael Walle <michael@walle.cc>
To:     Horatiu Vultur <horatiu.vultur@microchip.com>
Cc:     Vladimir Oltean <olteanv@gmail.com>, Steen.Hegelund@microchip.com,
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Subject: Re: [PATCH net-next v3 4/4] net: lan966x: Add ptp trap rules
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Am 2022-12-09 15:20, schrieb Horatiu Vultur:
> The 12/09/2022 15:05, Michael Walle wrote:
>> 
>> Am 2022-12-09 13:56, schrieb Vladimir Oltean:
>> > On Fri, Dec 09, 2022 at 01:58:57PM +0100, Horatiu Vultur wrote:
>> > > > Does it also work out of the box with the following patch if
>> > > > the interface is part of a bridge or do you still have to do
>> > > > the tc magic from above?
>> > >
>> > > You will still need to enable the TCAM using the tc command to have it
>> > > working when the interface is part of the bridge.
>> >
>> > FWIW, with ocelot (same VCAP mechanism), PTP traps work out of the box,
>> > no need to use tc. Same goes for ocelot-8021q, which also uses the
>> > VCAP.
>> > I wouldn't consider forcing the user to add any tc command in order for
>> > packet timestamping to work properly.
> 
> On ocelot, the vcap is enabled at port initialization, while on other
> platforms(lan966x and sparx5) you have the option to enable or disable.
> 
>> 
>> +1
>> Esp. because there is no warning. I.e. I tried this patch while
>> the interface was added on a bridge and there was no error
>> whatsoever.
> 
> What error/warning were you expecting to see here?

Scrap that. ptp4l is reporting an error in case the device is part
of a bridge:
Jan  1 02:33:04 buildroot user.info syslog: [9184.261] driver rejected 
most general HWTSTAMP filter

Nevertheless, from a users POV I'd just expect it to work. How
would I know what I need to do here?

-michael