Hardware timestamping in BCM43362

IEEE 1588 can be implemented solely in software to give accuracy in the sub-100 microsecond range. This is similar to that seen with other software implemented protocols such as Network Time Protocol (NTP - RFC 1305) and Simple Network Time Protocol (SNTP) methods that operate across the same network topology.

However, if timestamping is performed in the application layer, interrupts and other unpredictable software processes can introduce jitter and latency which may impair the synchronization. Even the use of a very precise external oscillator won’t overcome the stack jitter associated with a software-only 1588 implementation.

Most applications require the higher accuracy achieved by timestamping packets at the interface between the physical (PHY) and data link (MAC) layers (often referred to as “hardware timestamping”). IEEE 1588 hardware timestamping typically improves accuracy to 100 nanoseconds or better for certain network configurations, which is better than NTP, SNTP, Time-Triggered Protocol (TTP - www.ttpforum.org) and SERCOS (IEC 61491) methods.

http://www.ieee802.org/1/files/public/docs2008/avb-rhee-802-11n-timestamp-0908.pdf
http://www.ieee802.org/1/files/public/docs2013/tsn-phk-1AS-srv-802-11ak-links-0813-v1.pdf

Will hardware timestamping support be provided in wifi drivers?

Regards,
Aleksei

I want to know this too.
Have a project that depends on hardware timestamp.

I took a look a the BCM43362 datasheet and it mentions TSF, and various events from the PHY later, so it might be possible to implement this, but it’s way beyond my knowledge.

I’ve posted a question in the broadcom forums to see if someone can provide a more informed answer!