[E1000-devel] Clock frequency for 82579V

[Alexander I. <sh...@se...>]

Hi,

I'm trying to setup PTP on my 82579V, and it seems that clock speed is 3.84 times faster than expected.

$ phc_ctl /dev/ptp0 -- get wait 1 get
phc_ctl[33374.657]: clock time is 1479697143.971579879 or Mon Nov 21 05:59:03 2016
phc_ctl[33375.657]: process slept for 1.000000 seconds
phc_ctl[33375.657]: clock time is 1479697147.811930581 or Mon Nov 21 05:59:07 2016
$ python -c "print 1479697147.811930581 - 1479697143.971579879"
3.84035086632

Most likely, this device has 96MHz clock instead of 25MHz (these values
are taken from ./drivers/net/ethernet/intel/e1000e/netdev.c file).
How could I fix that?



The kernel is Debian 4.8.5-1.

Relevant dmesg lines:
[    1.287909] e1000e: Intel(R) PRO/1000 Network Driver - 3.2.6-k
[    1.561681] e1000e 0000:00:19.0 eth0: MAC: 10, PHY: 11, PBA No: FFFFFF-0FF

Relevant lsusb lines:
00:19.0 0200: 8086:1503 (rev 04)
        DeviceName:  LU1
        Subsystem: 8086:2031