Re: [net-next PATCH] octeontx2: Add PTP clock driver for Octeon PTM clock.

From: Vinicius Costa Gomes
Date: Thu Jan 25 2024 - 19:11:16 EST


Sai Krishna <saikrishnag@xxxxxxxxxxx> writes:

> The PCIe PTM(Precision time measurement) protocol provides precise
> coordination of events across multiple components like PCIe host
> clock, PCIe EP PHC local clocks of PCIe devices. This patch adds
> support for ptp clock based PTM clock. We can use this PTP device
> to sync the PTM time with CLOCK_REALTIME or other PTP PHC
> devices using phc2sys.
>
> Signed-off-by: Sai Krishna <saikrishnag@xxxxxxxxxxx>
> Signed-off-by: Naveen Mamindlapalli <naveenm@xxxxxxxxxxx>
> Signed-off-by: Sunil Kovvuri Goutham <sgoutham@xxxxxxxxxxx>
> ---

I can see that the same device id (PCI_DEVID_OCTEONTX2_PTP) is used by a
ethernet driver.

That brings me a question: why expose a different PTP chardev? In other
words, why can't you just implement .getcrosststamp() for that ethernet
device?


Cheers,
--
Vinicius