On 8/13/13 12:11 PM, "Gert-Jan Roskam" <[email protected]> wrote:
>Since I think this is an issue with the 82576 chip, I am sending this to >both the ptp and e1000 lists. > > A few months ago I had trouble with the INTEL 82576 and PTP. I got >errors like: recvmsg tx timestamp failed: Resource temporarily >unavailable. >It was suggested to switch to a newer kernel, which I did. >I went to kernel 3.7.10 and ptp 1.1 (which were current at that time). >PTP worked great for port 0. > >The 82576 has 2 ports. In our design the first port is connected to an >RJ45, the second to a SFP. >I never had ptp working with the SFP port. It constantly gives the >"recvmsg tx timestamp failed" errors. > > >At this moment I switched to ptp 1.3 and used the 4.3.0 igb driver from >sourceforge. >The SFP is still not working. The error message is: > poll tx timestamp timeout > port 1: send delay request failed > >The RJ45 port is working, but every now and then the same error occurs. > >On the errate sheet of the 82576 I found the following: > > 37. TimeSync: Missing Tx timestamps in SerDes mode > Problem: When transmitting a TimeSync packet in SerDes mode, >there is a probability that the > timestamp will not be sampled in the Tx Timestamp Value >registers and thus > TSYNCTXCTL.TXTT will not be set. > There is no issue when using 10/100/1000 BASE-T(Copper) mode. > Implication: Missing timestamps make it difficult for the >software to effectively implement the > TimeSync functionality. > > > >My questions are: > >- Could this error on the errato sheet be the cause that our SFP is not >working with PTP? > >- What could be the cause of spurious errors on the RJ45 port with >linuxptp_1.3 ( linuxptp_1.1 works good) > >- Are there people who use ptp with the 82576 chip without problems? > >Many thanks, >Gert-Jan Roskam Gert-Jan, Yes, that errata would be the explanation for why the SFP port does not work. For that port, the 82576 will be in SerDes mode, meaning you will occasionally be dropping Tx timestamps. For the occasional "hiccup" on the RJ45 side, if the 82576 tries to timestamp two outbound packets too quickly, it will fail to return the second one (since the hardware is busy timestamping the first one). What options are you running with ptp4l? -P should help reduce the number of failed timestamps on the RJ45 port. Cheers, Matthew Matthew Vick Linux Development Networking Division Intel Corporation ------------------------------------------------------------------------------ Get 100% visibility into Java/.NET code with AppDynamics Lite! It's a free troubleshooting tool designed for production. Get down to code-level detail for bottlenecks, with <2% overhead. Download for free and get started troubleshooting in minutes. http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk _______________________________________________ E1000-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/e1000-devel To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
