daniel-p-carvalho commented on PR #20161: URL: https://github.com/apache/nuttx/pull/20161#issuecomment-5706921602
Tried this on real hardware (RMII Ethernet, STM32H743BI). The SO_TIMESTAMPING infrastructure itself is all correct - setsockopt/getsockopt, cmsg, the error queue, poll(POLLPRI), everything works exactly as expected. What I found: on real hardware, TX timestamp delivery depends on the transmitted frame looping back through the receive path (io_conn match in pkt_in()). That works fine in the simulator (which already has that loopback simulated), but on a real Ethernet board, full-duplex, point-to-point, the transmitted frame never shows up on RX again - so poll/recvmsg never fire. Probably just wasn't caught because testing this needs real physical hardware with a second point on the network, not just the simulator. I put together a prototype to close that last gap: a new function (pkt_tx_timestamp_complete()) that lets the driver deliver the timestamp directly from the TX-complete interrupt, without depending on any loopback - which is how hardware TX timestamping normally works (read the completed descriptor). Wired it into the STM32H7 driver as a reference and validated it end to end: poll/recvmsg now deliver correctly. Left the branches available in case they're useful: - daniel-p-carvalho/apache-nuttx#test/pr20161-h7-tx-timestamp (the new delivery path + driver wiring) - daniel-p-carvalho/nuttx-apps#test/pr20161-h7-tx-timestamp (the test I used to validate it) Happy to help if there's anything I can do. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
