[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 5 Jun 2019 19:37:43 -0700
From: Richard Cochran <richardcochran@...il.com>
To: Shalom Toledo <shalomt@...lanox.com>
Cc: Ido Schimmel <idosch@...sch.org>,
"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
"davem@...emloft.net" <davem@...emloft.net>,
Jiri Pirko <jiri@...lanox.com>,
Petr Machata <petrm@...lanox.com>, mlxsw <mlxsw@...lanox.com>,
Ido Schimmel <idosch@...lanox.com>
Subject: Re: [PATCH net-next 4/9] mlxsw: reg: Add Management UTC Register
On Wed, Jun 05, 2019 at 06:55:18PM +0000, Shalom Toledo wrote:
> On 05/06/2019 20:23, Richard Cochran wrote:
> > On Wed, Jun 05, 2019 at 11:30:06AM +0000, Shalom Toledo wrote:
> >> On 04/06/2019 17:17, Richard Cochran wrote:
> >>> On Mon, Jun 03, 2019 at 03:12:39PM +0300, Ido Schimmel wrote:
> >>>> From: Shalom Toledo <shalomt@...lanox.com>
> >>>>
> >>>> The MTUTC register configures the HW UTC counter.
> >>>
> >>> Why is this called the "UTC" counter?
> >>>
> >>> The PTP time scale is TAI. Is this counter intended to reflect the
> >>> Linux CLOCK_REALTIME system time?
> >>
> >> Exactly. The hardware doesn't have the ability to convert the FRC to UTC, so
> >> we, as a driver, need to do it and align the hardware with this value.
> >
> > What does "FRC" mean?
>
> Free Running Counter
Okay, so then you want to convert it into TAI (for PTP) rather than UTC.
Thanks,
Richard
Powered by blists - more mailing lists