Commit Graph

3 Commits

Author SHA1 Message Date
Yangbo Lu
5c5416f5d4 net: dsa: no longer clone skb in core driver
It was a waste to clone skb directly in dsa_skb_tx_timestamp().
For one-step timestamping, a clone was not needed. For any failure of
port_txtstamp (this may usually happen), the skb clone had to be freed.

So this patch moves skb cloning for tx timestamp out of dsa core, and
let drivers clone skb in port_txtstamp if they really need.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Tested-by: Kurt Kanzenbach <kurt@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 14:10:15 -07:00
Yangbo Lu
cf536ea3c7 net: dsa: no longer identify PTP packet in core driver
Move ptp_classify_raw out of dsa core driver for handling tx
timestamp request. Let device drivers do this if they want.
Not all drivers want to limit tx timestamping for only PTP
packet.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Tested-by: Kurt Kanzenbach <kurt@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 14:10:15 -07:00
Kamil Alkhouri
f0d4ba9eff net: dsa: hellcreek: Add support for hardware timestamping
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>
2020-11-05 14:04:49 -08:00