RE: [PATCH net-next V3] dt-bindings: net: ethernet-controller: Add ptp-hardware-clock

From: Gaddam, Sarath Babu Naidu
Date: Thu Mar 16 2023 - 06:53:57 EST




> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Sent: Tuesday, March 14, 2023 9:16 PM
> To: Gaddam, Sarath Babu Naidu
> <sarath.babu.naidu.gaddam@xxxxxxx>; davem@xxxxxxxxxxxxx;
> edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx;
> robh+dt@xxxxxxxxxx; richardcochran@xxxxxxxxx
> Cc: krzysztof.kozlowski+dt@xxxxxxxxxx; netdev@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> yangbo.lu@xxxxxxx; Pandey, Radhey Shyam
> <radhey.shyam.pandey@xxxxxxx>; Sarangi, Anirudha
> <anirudha.sarangi@xxxxxxx>; Katakam, Harini
> <harini.katakam@xxxxxxx>; git (AMD-Xilinx) <git@xxxxxxx>
> Subject: Re: [PATCH net-next V3] dt-bindings: net: ethernet-controller:
> Add ptp-hardware-clock
>
> On 08/03/2023 06:44, Sarath Babu Naidu Gaddam wrote:
> > There is currently no standard property to pass PTP device index
> > information to ethernet driver when they are independent.
> >
> > ptp-hardware-clock property will contain phandle to PTP clock node.
> >
> > Its a generic (optional) property name to link to PTP phandle to
> > Ethernet node. Any future or current ethernet drivers that need a
> > reference to the PHC used on their system can simply use this generic
> > property name instead of using custom property implementation in
> their
> > device tree nodes."
> >
> > Signed-off-by: Sarath Babu Naidu Gaddam
> > <sarath.babu.naidu.gaddam@xxxxxxx>
> > Acked-by: Richard Cochran <richardcochran@xxxxxxxxx>
> > ---
> >
> > Freescale driver currently has this implementation but it will be good
> > to agree on a generic (optional) property name to link to PTP phandle
> > to Ethernet node. In future or any current ethernet driver wants to
> > use this method of reading the PHC index,they can simply use this
> > generic name and point their own PTP clock node, instead of creating
> > separate property names in each ethernet driver DT node.
>
> Again, I would like to see an user of this. I asked about this last time and
> nothing was provided.
>
> So basically you send the same thing hoping this time will be accepted...

Apologies for miscommunication. As of now, we see only freescale driver
has this type of implementation but with different binding name. we do
not have the hardware to test this. However, I am going to upstream PTP
support in AMD/Xilinx axiethernet driver that will be user of this binding.

I will pick up on this binding again along with consumer driver and address
your review comments.

Thanks for the review.

Thanks,
Sarath