AnsweredAssumed Answered

missing capabilities about SW timestamping

Question asked by Jason yang on Oct 22, 2018
Latest reply on Nov 4, 2018 by Yiping Wang


I am using LinuxPTP on two LS1043 boards. I can see good results when running as Hardware timestamping mode. And I thought I could also use software timestamping.

But when I try to use SW timestamping mode with the "-S" option, it fails:


[root@OpenIL:~]# ptp4l -i eth0 -m -S
ptp4l[15.267]: interface 'eth0' does not support requested timestamping mode
failed to create a clock


 And the ethtool shows:

[root@OpenIL:~]# ethtool -T eth0
Time stamping parameters for eth0:

            hardware-transmit (SOF_TIMESTAMPING_TX_HARDWARE)

            hardware-receive (SOF_TIMESTAMPING_RX_HARDWARE)

            hardware-receive (SOF_TIMESTAMPING_RX_HARDWARE)

PTP Hardware Clock: 0
Hardware Transmit Timestamp Modes:

                off       (HWTSTAMP_TX_OFF)

                on       (HWTSTAMP_TX_ON)

Hardware Receive Filter Modes:

               none      (HWTSTAMP_FILTER_NONE)

               all           (HWTSTAMP_FILTER_ALL)


Obviously, there are missing capabilities about SW timestamping(SOF_TIMESTAMPING_..._SOFTWARE).

Does the LinuxPTP on LS1043 board support the software timestamping?

Or is there any change or support of Linux Kernel configuration need for SW timestamping?

Or it's a driver problem?


Thank you for any help!