lkml.org 
[lkml]   [2017]   [Sep]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH net-next RFC 0/9] net: dsa: PTP timestamping for mv88e6xxx
Brandon,

On Thu, Sep 28, 2017 at 10:25:32AM -0500, Brandon Streiff wrote:
> - Patch #2: We expose the switch time as a PTP clock but don't support
> adjustment (max_adj=0).

The driver should implement a cyclecounter/timecounter.

> Our platform adjusted a systemwide oscillator
> from userspace, so we didn't need adjustment at this layer, but other
> PTP clock drivers support this and we probably should too.

We don't currently have any way to support this kind of HW or anything
like an external VCO. I would like to find a way to do this, but that
is a different kettle of fish as it might require changes in the PHC
subsystem. For this driver, I think we should get it merged using the
cyclecounter/timecounter (as that will benefit lots of users) and
worry about the external oscillator later.

> Feedback is appreciated.

I happy to see this series. I just finished porting an out-of-tree
PHC driver for the Marvell mv88e635x, and I want to mainline it, but I
also have a few uglies.

Unfortunately I am in the middle of a move right now, and so my review
of this series might have to wait a bit. However, I am looking
forward to comparing notes, and then getting this support in.

Thanks,
Richard

\
 
 \ /
  Last update: 2017-09-29 11:44    [W:0.846 / U:0.456 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site