Currently, network /system cross-timestamping is performed in the
PTP_SYS_OFFSET ioctl. The PTP clock driver reads gettimeofday() and
the gettime64() callback provided by the driver. The cross-timestamp
is best effort where the latency between the capture of system time
(getnstimeofday()) and the device time (driver callback) may be
significant.
The getcrosststamp() callback and corresponding PTP_SYS_OFFSET_PRECISE
ioctl allows the driver to perform this device/system correlation when
for example cross timestamp hardware is available. Modern Intel
systems can do this for onboard Ethernet controllers using the ART
counter. There is virtually zero latency between captures of the ART
and network device clock.
The capabilities ioctl (PTP_CLOCK_GETCAPS), is augmented allowing
applications to query whether or not drivers implement the
getcrosststamp callback, providing more precise cross timestamping.
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: kevin.b.stanton@intel.com
Cc: kevin.j.clarke@intel.com
Cc: hpa@zytor.com
Cc: jeffrey.t.kirsher@intel.com
Cc: netdev@vger.kernel.org
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Christopher S. Hall <christopher.s.hall@intel.com>
[jstultz: Commit subject tweaks]
Signed-off-by: John Stultz <john.stultz@linaro.org>
When compiling Documentation/ptp/testptp.c the following compiler
warnings are printed out:
Documentation/ptp/testptp.c: In function ‘main’:
Documentation/ptp/testptp.c:367:11: warning: format ‘%lld’ expects argument
of type ‘long long int’, but argument 3 has type ‘__s64’ [-Wformat=]
event.t.sec, event.t.nsec);
^
Documentation/ptp/testptp.c:505:5: warning: format ‘%lld’ expects argument
of type ‘long long int’, but argument 2 has type ‘__s64’ [-Wformat=]
(pct+2*i)->sec, (pct+2*i)->nsec);
^
Documentation/ptp/testptp.c:507:5: warning: format ‘%lld’ expects argument
of type ‘long long int’, but argument 2 has type ‘__s64’ [-Wformat=]
(pct+2*i+1)->sec, (pct+2*i+1)->nsec);
^
Documentation/ptp/testptp.c:509:5: warning: format ‘%lld’ expects argument
of type ‘long long int’, but argument 2 has type ‘__s64’ [-Wformat=]
(pct+2*i+2)->sec, (pct+2*i+2)->nsec);
This happens because __s64 is by default defined as "long" on ppc64,
not as "long long". However, to fix these warnings, it's possible to
define the __SANE_USERSPACE_TYPES__ so that __s64 gets defined to
"long long" on ppc64, too.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch brings back the makefile called testptp.mk which was removed
in commit adb19fb66e (Documentation: add makefiles for more targets).
While the idea of that commit was to improve build coverage of the
examples, the new Makefile is unable to cross compile the testptp program.
In contrast, the deleted makefile was able to do this just fine.
This patch fixes the regression by restoring the original makefile.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add some missing files to .gitignore.
Push Documentation/.gitignore down into subdirectories.
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Fix a few warnings that gcc emits during a default build.
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Add a bunch of previously unbuilt source files to the Documentation build
machinery.
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
clock_adjtime was included in glibc 2.14. _GNU_SOURCE must be defined
to make it available.
Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Cc: Richard Cochran <richardcochran@gmail.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Cc: Dong Zhu <bluezhudong@gmail.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Cc: Dong Zhu <bluezhudong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Manfred Rudigier <manfred.rudigier@omicron.at>
Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a option to the test program that lists the
programmable pins on a PTP Hardware Clock device, assuming there
are any such pins. A second option lets the user reprogram the
auxiliary function of a single pin.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the trigger/event is hardcoded to 0, this patch adds
a new command line argument -i to select an arbitrary trigger/
event.
Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add a method into testptp.c to measure the time offset
between phc and system clock through the ioctl PTP_SYS_OFFSET.
Signed-off-by: Dong Zhu <bluezhudong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds an infrastructure for hardware clocks that implement
IEEE 1588, the Precision Time Protocol (PTP). A class driver offers a
registration method to particular hardware clock drivers. Each clock is
presented as a standard POSIX clock.
The ancillary clock features are exposed in two different ways, via
the sysfs and by a character device.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John Stultz <john.stultz@linaro.org>
