Hi Vladimir, On Friday, 30 October 2020, 19:24:47 CET, Vladimir Oltean wrote: > On Thu, Oct 22, 2020 at 12:17:48PM +0200, Christian Eggers wrote: > > I tried to study the effect of setting the ocmode bit on the KSZ either to > > master or to slave. The main visible change is, that some PTP message > > types > > are be filtered out on RX: > > - in "master" mode, "Sync" messages from other nodes will not be received > > (but everything else like "Announce" seem to work) > > - in "slave" mode, "Delay_Req" messages from other nodes will not be > > received > Could you dump the contents of your REG_PTP_MSG_CONF2 register? runtime register value is 0x1004 (matches default value from the data sheet). The Linux driver doesn't touch this register. Below is a dump of all PTP related (global) registers. regards Christian KSZ9563 (Ethernet switch) Global IEEE 1588 PTP CLKCTRL 0002 SWFA enabled CLKSADJ NOP PTPSD subtract CLKREAD NOP CLKWRITE NOP CLKCADJ disabled EN enabled RESET normal RTCCP 0002 PHASE 16ns RTCNS 17D72FF0 NANOSECONDS 399978480 RTCS 00000023 SECONDS 35 RTCSUBNS 00000000 RATEDIR subtract TEMPADJ permanent SUBNS 0 RTCTMPADJ 00000000 CYCLES 0 MSGCFG1 007D MODEEN enabled IEEE802.3 enabled UDPv4 enabled UDPv6 enabled TCMODE P2P OCMODE slave MSGCFG2 1004 UNICASTEN both ALTMASTER disabled PRIOTX event only CHKSYNFU disabled CHKDLY disabled CHKPDLY disabled DROP disabled CHKDOM disabled IPv4CHKSUM calc DOMVER 0200 VERSION 2 DOMAIN 0 UNITIDX 00000000 GPIO_IDX GPIO_1 TS_IDX Unit 0 TRIG_IDX Unit 0