linuxptp-users

[Linuxptp-users] PTP implementation on AM335x

[Hardik G. <har...@gm...>]

Hello,

I am working on AM335x running on linux -3.2.0

I want to implement PTP and I have done the following configuration

   1. Select PPS Support - Device Drivers ---> PPS Support ---> <*> PPS
   Support
   2. Select PTP Clock Support - Device Drivers ---> PTP Clock Support --->
   <*> PTP Clock Support
   3. Select TI CPTS PTP Clock - Device Drivers ---> PTP Clock Support --->
   <*> TI CPTS as PTP clock

As per my study AM335x supports Hardware time stamping at MAC layer.

In order to confirm this I am using ethtool.

root@phyCORE-AM335x:~ ./ethtool -T eth0
Time stamping parameters for eth0:
Cannot get device time stamping settings: Operation not supported

starting from which kernel version support is there ?
how to confirm HW time stamping feature ?

Regards,
Hardik A Gohil

Re: [Linuxptp-users] PTP implementation on AM335x

[Richard C. <ric...@gm...>]

On Mon, Nov 21, 2016 at 02:20:46PM +0800, Hardik Gohil wrote:
> starting from which kernel version support is there ?

Check out the driver support matrix at:

   http://linuxptp.sourceforge.net

There you will find:

    | cpts       | Texas Instruments am335x |     3.8 |

This information is also in the README.org file.

> how to confirm HW time stamping feature ?

ethtool -T is a good start.

HTH,
Richard

Re: [Linuxptp-users] PTP implementation on AM335x

[Hardik G. <har...@gm...>]

On Nov 21, 2016 9:30 PM, "Richard Cochran" <ric...@gm...> wrote:
>
> On Mon, Nov 21, 2016 at 02:20:46PM +0800, Hardik Gohil wrote:
> > starting from which kernel version support is there ?
>
> Check out the driver support matrix at:
>
>    http://linuxptp.sourceforge.net
>
> There you will find:
>
>     | cpts       | Texas Instruments am335x |     3.8 |
>

Does this means support is there from kernel 3.8
> This information is also in the README.org file.
>
> > how to confirm HW time stamping feature ?
>
> ethtool -T is a good start.
Yes I have tried this method and posted the problem in previous message.

>
> HTH,
> Richard

Re: [Linuxptp-users] PTP implementation on AM335x

[Richard C. <ric...@gm...>]

On Mon, Nov 21, 2016 at 10:13:32PM +0800, Hardik Gohil wrote:
> Does this means support is there from kernel 3.8

Yes.

> Yes I have tried this method and posted the problem in previous message.

You said you were running kernel 3.2.  That won't work.  Use kernel
3.8 or later.

BTW, the '-T' ethtool option only works on kernel 3.5 or later.

HTH,
Richard

Re: [Linuxptp-users] PTP implementation on AM335x

[Hardik G. <har...@gm...>]

Hello,

Thank you.

so for HW time stamping at CPTS core I need to change kernel to 3.8 or
later.

what is the accuracy of time sync ??





Regards,
Hardik A Gohil

On Tue, Nov 22, 2016 at 2:18 AM, Richard Cochran <ric...@gm...>
wrote:

> On Mon, Nov 21, 2016 at 10:13:32PM +0800, Hardik Gohil wrote:
> > Does this means support is there from kernel 3.8
>
> Yes.
>
> > Yes I have tried this method and posted the problem in previous message.
>
> You said you were running kernel 3.2.  That won't work.  Use kernel
> 3.8 or later.
>
> BTW, the '-T' ethtool option only works on kernel 3.5 or later.
>
> HTH,
> Richard
>
>

Re: [Linuxptp-users] PTP implementation on AM335x

[Richard C. <ric...@gm...>]

On Tue, Nov 22, 2016 at 02:21:07PM +0800, Hardik Gohil wrote:
> what is the accuracy of time sync ??

It depends.

Cheers,
Richard

Re: [Linuxptp-users] PTP implementation on AM335x

[Hardik G. <har...@gm...>]

Hello,

How can get details on this ?

I will be using HW time stamping at MAC layer at CPTS core for TI Chip.

and linuxptp to synchronize clock between system clock and PTP hardware
clock.

Master clock is GPS receiver



Regards,
Hardik A Gohil

On Tue, Nov 22, 2016 at 4:18 PM, Richard Cochran <ric...@gm...>
wrote:

> On Tue, Nov 22, 2016 at 02:21:07PM +0800, Hardik Gohil wrote:
> > what is the accuracy of time sync ??
>
> It depends.
>
> Cheers,
> Richard
>