RE: [RFC 0/3] ptp: Add esterror support

["Arinzon, David" <darinzon@amazon.com>]

> >
> >
> > On 15/08/2024 02:41, Jakub Kicinski wrote:
> >> On Tue, 13 Aug 2024 12:55:59 +0000 Maciek Machnikowski wrote:
> >>> This patch series implements handling of timex esterror field by ptp
> >>> devices.
> >>>
> >>> Esterror field can be used to return or set the estimated error of
> >>> the clock. This is useful for devices containing a hardware clock
> >>> that is controlled and synchronized internally (such as a time card)
> >>> or when the synchronization is pushed to the embedded CPU of a DPU.
> >>>
> >>> Current implementation of ADJ_ESTERROR can enable pushing current
> >>> offset of the clock calculated by a userspace app to the device,
> >>> which can act upon this information by enabling or disabling
> >>> time-related functions when certain boundaries are not met (eg.
> >>> packet launchtime)
> >>
> >> Please do CC people who are working on the VM / PTP / vdso thing, and
> >> time people like tglx. And an implementation for a real device would
> >> be nice to establish attention.
> >
> > Noted - will CC in future releases.
> >
> > AWS planned the implementation in ENA driver - will work with David on
> > making it part of the patchset once we "upgrade" from an RFC - but
> > wanted to discuss the approach first.
> 
> I can implement the interface for OCP TimeCard too, I think we have HW
> information about it already.

CC Amit Bernstein (AWS, ENA driver).