This is a simple servo that provides the NTP SHM reference clock. It
doesn't make any clock adjustments and it always returns with the
unlocked state. It writes all samples to the SHM segment and another
process (e.g. chronyd or ntpd) is needed to read the samples and
actually synchronize the clock. The SHM segment number is set to the PTP
domain number to allow multiple SHM reference clocks running at the same
time.
This is mainly useful when other time sources are available on the
system (e.g. NTP, hardware reference clocks, or other PTP domains)
and a fallback to/from PTP is needed.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Most PHC drivers implement stepping (ADJ_SETOFFSET) by reading the
clock, adjusting the value by the offset and writing it back. This is
not perfectly accurate and if the operation is slow (e.g. due to PCIe
latencies), the error can be in microseconds.
Increase the default first step threshold from 100 nanoseconds to 20
microseconds to step only when the initial offset is larger than
the error in the step.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
This servo uses linear regression to estimate current time and
frequency error. The number of points used in the regression is
variable (from 4 to 64 in powers of 2) and is selected by a long-term
statistic of the prediction error.
Future improvements could include tracking of sudden frequency changes
(e.g. due to temperature variations), better stability of the error
statistic when a large offset is corrected, options to set the speed of
the adaptation, minimum and maximum number of points, or an option to
prefer frequency accuracy over time accuracy.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
These settings will be useful for all implemented servos, so move them
to the common servo code to avoid duplication. The configuration options
are renamed, but the they can be still set by their old names.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Check the sanity of the synchronized clock by comparing its uncorrected
frequency with the system monotonic clock. When the measured frequency
offset is larger than the value of the sanity_freq_limit option (20% by
default), a warning message will be printed and the servo will be reset.
Setting the option to zero disables the check.
This is useful to detect when the clock is broken or adjusted by another
program.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Current pi servo steps clock without any condition on start.
This patch adds a new servo option "configured_pi_f_offset". The option is similar
to configured_pi_offset but only affects in the first clock update. Therefore,
if this option is set as 0.0, we can prevent clock step on start.
The new servo option can be specified from phc2sys by using -F option.
This feature is usefull when we need to restart phc2sys without system
clock jump. Restarting phc2sys is needed to change its configuration.
changes since v2:
- manual page fix.
- also apply max_offset along with max_f_offset in servo step1.
- add a variable to check if first update is done.
changes since v1:(http://sourceforge.net/mailarchive/message.php?msg_id=31039874)
- remake as a new servo option.
Signed-off-by: Ken ICHIKAWA <ichikawa.ken@jp.fujitsu.com>
Options without parameters are now grouped together at the beginning of line
for better legibility.
Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
The default zero offset can lead to misalignment between system clocks or wrong
time to be broadcast to the domain. Therefore we require setting offset upon
invocation.
Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
This patch modifies phc2sys to enable the use of interface names in clock_open
rather than having to do that by hand. This enables cleaner use of the -s and -c
options as they can accept interface names. This also enables the user to set
the slave clock by network interface as well.
-v2-
* fix clock_open as it used device instead of phc_device in the final call to phc_open
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Add kernel_leap option for ptp4l and -x option for phc2sys to disable
setting of the STA_INS/STA_DEL bit to slowly correct the one-second
offset by servo.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Modify the pmc to allow non-blocking operation. Run it on each clock
update to have the sync offset updated from currentUtcOffset with every
other call.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Add new options to ptp4l and phc2sys to print summary statistics of the
clock instead of the individual samples.
[ RC - Fix () function prototype with (void).
- Use unsigned for sample counter.
- Fix over-zealous line breaks. ]
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Use pr_* functions to print messages and add -m, -q, -l options to allow
configuration of the printing level and where should be the messages sent.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Add a new option to wait for ptp4l to be in a synchronized state.
Periodically check PORT_DATA_SET and wait until there is a port in
SLAVE, MASTER or GRAND_MASTER state. Also, set the default
synchronization offset according to the currentUtcOffset value from
TIME_PROPERTIES_DATA_SET and the direction of the clock synchronization.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
The PPS time stamps are always made by the system clock, don't allow
running the PPS loop with other clocks.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
In the PPS loop, instead of setting the system clock from the PHC only
once on start, read PHC with each PPS sample and use the time stamp to
get the whole number of seconds in the offset. This will prevent phc2sys
from losing track of the system clock.
Also, check if the PPS is synchronized to the PHC.
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Miroslav Lichvar
Jiri Benc
Ken ICHIKAWA
Libor Pechacek
Jacob Keller
Richard Cochran