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Message-ID: <20230116130243.ghtythag3og6745y@skbuf> References: <20230116102440.27189-1-nikhil.gupta@nxp.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230116102440.27189-1-nikhil.gupta@nxp.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230116_050252_256001_FA79B813 X-CRM114-Status: GOOD ( 12.50 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Nikhil, On Mon, Jan 16, 2023 at 03:54:40PM +0530, nikhil.gupta@nxp.com wrote: > From: Nikhil Gupta > > 1588 driver loses about 1us in adjtime operation at PTP slave. > This is because adjtime operation uses a slow non-atomic tmr_cnt_read() > followed by tmr_cnt_write() operation. > In the above sequence, since the timer counter operation keeps > incrementing, it leads to latency. > The tmr_offset register (which is added to TMR_CNT_H/L register > gives the current time) must be programmed with the delta > nanoseconds. > > Signed-off-by: Nikhil Gupta > Reviewed-by: Yangbo Lu > --- Your patch breaks eTSEC1 [ and eTSEC2 ] on LS1021A. Before: root@black:~# ip link set eth1 up root@black:~# [ 54.321664] fsl-gianfar soc:ethernet@2d50000 eth1: Link is Up - 1Gbps/Full - flow control off [ 54.331331] IPv6: ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready root@black:~# ptp4l -i eth1 -2 -P -m ptp4l[57.231]: selected /dev/ptp0 as PTP clock ptp4l[57.351]: port 1: INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[57.353]: port 0: INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[57.355]: port 1: link down ptp4l[57.356]: port 1: LISTENING to FAULTY on FAULT_DETECTED (FT_UNSPECIFIED) ptp4l[57.455]: selected local clock 001f7b.fffe.630228 as best master ptp4l[57.458]: port 1: assuming the grand master role ptp4l[57.464]: selected local clock 001f7b.fffe.630228 as best master ptp4l[57.466]: port 1: assuming the grand master role [ 60.086366] fsl-gianfar soc:ethernet@2d50000 eth1: Link is Up - 1Gbps/Full - flow control off ptp4l[60.089]: port 1: link up ptp4l[60.183]: port 1: FAULTY to LISTENING on INIT_COMPLETE ptp4l[66.713]: port 1: LISTENING to MASTER on ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES ptp4l[66.714]: selected local clock 001f7b.fffe.630228 as best master ptp4l[66.715]: port 1: assuming the grand master role ptp4l[102.753]: port 1: new foreign master 00049f.fffe.05f4ad-1 ptp4l[106.757]: selected best master clock 00049f.fffe.05f4ad ptp4l[106.758]: port 1: MASTER to UNCALIBRATED on RS_SLAVE ptp4l[107.763]: master offset -363290000824 s0 freq +0 path delay 735 ptp4l[108.764]: master offset -363289992530 s1 freq +8285 path delay 736 ptp4l[109.767]: master offset -1648 s2 freq +6637 path delay 736 ptp4l[109.768]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED ptp4l[110.770]: master offset -6 s2 freq +7784 path delay 736 ptp4l[111.772]: master offset 491 s2 freq +8280 path delay 735 ptp4l[112.773]: master offset 495 s2 freq +8431 path delay 735 ptp4l[113.776]: master offset 342 s2 freq +8426 path delay 731 ptp4l[114.778]: master offset 198 s2 freq +8385 path delay 724 ptp4l[115.781]: master offset 100 s2 freq +8346 path delay 722 After: root@black:~# ip link set eth1 up root@black:~# [ 311.001924] fsl-gianfar soc:ethernet@2d50000 eth1: Link is Up - 1Gbps/Full - flow control off [ 311.013236] IPv6: ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready root@black:~# ptp4l -i eth1 -2 -P -m ptp4l[333.797]: selected /dev/ptp0 as PTP clock ptp4l[333.916]: port 1: INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[333.918]: port 0: INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[333.919]: port 1: link down ptp4l[333.919]: port 1: LISTENING to FAULTY on FAULT_DETECTED (FT_UNSPECIFIED) ptp4l[334.012]: selected local clock 001f7b.fffe.630228 as best master ptp4l[334.013]: port 1: assuming the grand master role [ 336.626213] fsl-gianfar soc:ethernet@2d50000 eth1: Link is Up - 1Gbps/Full - flow control off ptp4l[336.631]: port 1: link up ptp4l[336.713]: port 1: FAULTY to LISTENING on INIT_COMPLETE ptp4l[343.832]: port 1: LISTENING to MASTER on ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES ptp4l[343.833]: selected local clock 001f7b.fffe.630228 as best master ptp4l[343.834]: port 1: assuming the grand master role ptp4l[344.873]: port 1: new foreign master 00049f.fffe.05f4ad-1 ptp4l[348.879]: selected best master clock 00049f.fffe.05f4ad ptp4l[348.879]: port 1: MASTER to UNCALIBRATED on RS_SLAVE ptp4l[349.888]: master offset 215392521359 s0 freq +0 path delay 737 ptp4l[350.890]: master offset 215392529808 s1 freq +8433 path delay 738 ptp4l[351.896]: master offset 215392529845 s2 freq +32767999 path delay 735 ptp4l[351.896]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED ptp4l[352.897]: master offset 215359819000 s2 freq +32767999 path delay 731 ptp4l[353.899]: master offset 215326980590 s2 freq +32767999 path delay 731 ptp4l[354.900]: master offset 215294167912 s2 freq +32767999 path delay 729 ptp4l[355.902]: master offset 215261357366 s2 freq +32767999 path delay 725 ptp4l[356.905]: master offset 215228532618 s2 freq +32767999 path delay -24741 ptp4l[357.907]: master offset 215195717627 s2 freq +32767999 path delay -51970 ptp4l[358.909]: master offset 215162898062 s2 freq +32767999 path delay -57014 ptp4l[359.912]: master offset 215130057602 s2 freq +32767999 path delay -59714 ptp4l[360.915]: master offset 215097182978 s2 freq +32767999 path delay -60737 ptp4l[361.917]: master offset 215064357344 s2 freq +32767999 path delay -60783 I have forwarded you an internal email which gives more details about how the 1588 block was integrated on the 3 eTSEC ports on LS1021A. The general takeaway is: please don't break that SoC, and NACK for this patch. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel