Re: [Linuxptp-users] recvmsg tx timestamp failed: Resource temporarily unavailable

[Rayagond K. <ray...@gm...>]

On 06/02/2013, Richard Cochran <ric...@gm...> wrote:
> On Wed, Feb 06, 2013 at 07:40:29PM +0530, Rayagond Kokatanur wrote:
>
>> Following are log message on SLAVE side,
> ...
>> ptp4l[3529.856]: negative path delay -273111420
>> ptp4l[3529.856]: path_delay = (t2 - t3) + (t4 - t1)
>> ptp4l[3529.856]: t2 - t3 = -1331967748
>> ptp4l[3529.856]: t4 - t1 = +785744908
>> ptp4l[3529.856]: c1          0
>> ptp4l[3529.856]: c2          0
>> ptp4l[3529.856]: c3          0
>> ptp4l[3530.070]: master offset -1360149853961689539 s0 adj      +0 path
>> delay -273111420
>
> It looks like your driver's time stamps are not correct. Have you
> verified that the time stamps are working with your driver?

How to verify that time stamp are working with my driver ?

I send time stamp like this to stack,

1. read the tx/rx timestamp low and high value into "u64 ns;" variable.
2. convert the raw timstamp value to ktime using - "ns_to_ktime()" api.
3. assign the converted value to .hwtstamp field of struct
skb_shared_hwtstamps struct.
3. finally pass the struct skb_shared_hwtstamps to stack.

I am not manipulating other field of struct skb_shared_hwtstamps ie syststamp.

Also I have configured device to capture time stamp for all received packets.

Please let me if my procedure is wrong ?

Thank you

Rayagond

> Richard
>