The switch has two controllable I/Os which are usually connected to LEDs. This
is useful to immediately visually see the PTP status.
These provide two signals:
* is_gm
This LED can be activated if the current device is the grand master in that
PTP domain.
* sync_good
This LED can be activated if the current device is in sync with the network
time.
Expose these via the LED framework to be controlled via user space
e.g. linuxptp.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The switch has the ability to take hardware generated time stamps per port for
PTPv2 event messages in Rx and Tx direction. That is useful for achieving needed
time synchronization precision for TSN devices/switches. So add support for it.
There are two directions:
* RX
The switch has a single register per port to capture a timestamp. That
mechanism is not used due to correlation problems. If the software processing
is too slow and a PTPv2 event message is received before the previous one has
been processed, false timestamps will be captured. Therefore, the switch can
do "inline" timestamping which means it can insert the nanoseconds part of
the timestamp directly into the PTPv2 event message. The reserved field (4
bytes) is leveraged for that. This might not be in accordance with (older)
PTP standards, but is the only way to get reliable results.
* TX
In Tx direction there is no correlation problem, because the software and the
driver has to ensure that only one event message is "on the fly". However,
the switch provides also a mechanism to check whether a timestamp is
lost. That can only happen when a timestamp is read and at this point another
message is timestamped. So, that lost bit is checked just in case to indicate
to the user that the driver or the software is somewhat buggy.
Signed-off-by: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The switch has internal PTP hardware clocks. Add support for it. There are three
clocks:
* Synchronized
* Syntonized
* Free running
Currently the synchronized clock is exported to user space which is a good
default for the beginning. The free running clock might be exported later
e.g. for implementing 802.1AS-2011/2020 Time Aware Bridges (TAB). The switch
also supports cross time stamping for that purpose.
The implementation adds support setting/getting the time as well as offset and
frequency adjustments. However, the clock only holds a partial timeofday
timestamp. This is why we track the seconds completely in software (see overflow
work and last_ts).
Furthermore, add the PTP multicast addresses into the FDB to forward that
packages only to the CPU port where they are processed by a PTP program.
Signed-off-by: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Kurt Kanzenbach