lkml.org 
[lkml]   [2023]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH net-next] net: ethernet: ti: am65-cpts: adjust estf following ptp changes
On Tue, Mar 21, 2023 at 11:56:00AM +0530, Siddharth Vadapalli wrote:
> From: Grygorii Strashko <grygorii.strashko@ti.com>
>
> When the CPTS clock is synced/adjusted by running linuxptp (ptp4l/phc2sys),
> it will cause the TSN EST schedule to drift away over time. This is because
> the schedule is driven by the EstF periodic counter whose pulse length is
> defined in ref_clk cycles and it does not automatically sync to CPTS clock.
> _______
> _|
> ^
> expected cycle start time boundary
> _______________
> _|_|___|_|
> ^
> EstF drifted away -> direction
>
> To fix it, the same PPM adjustment has to be applied to EstF as done to the
> PHC CPTS clock, in order to correct the TSN EST cycle length and keep them
> in sync.
>
> Drifted cycle:
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230373377017
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230373877017
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230374377017
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230374877017
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230375377017
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230375877023
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230376377018
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230376877018
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635968230377377018
>
> Stable cycle:
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863193375473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863193875473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863194375473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863194875473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863195375473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863195875473
> AM65_CPTS_EVT: 7 e1:01770001 e2:000000ff t:1635966863196375473
>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Acked-by: Richard Cochran <richardcochran@gmail.com>

\
 
 \ /
  Last update: 2023-03-27 01:11    [W:2.665 / U:1.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site