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Vladimir Oltean says: ==================== PTP support for the SJA1105 DSA driver This patchset adds the following: - A timecounter/cyclecounter based PHC for the free-running timestamping clock of this switch. - A state machine implemented in the DSA tagger for SJA1105, which keeps track of metadata follow-up Ethernet frames (the switch's way of transmitting RX timestamps). Clock manipulations on the actual hardware PTP clock will have to be implemented anyway, for the TTEthernet block and the time-based ingress policer. v3 patchset can be found at: https://lkml.org/lkml/2019/6/4/954 Changes from v3: - Made it compile with the SJA1105 DSA driver and PTP driver as modules. - Reworked/simplified/fixed some issues in 03/17 (dsa_8021q_remove_header) and added an ASCII image that illustrates the transformation that is taking place. - Removed a useless check for sja1105_is_link_local from 16/17 (RX timestamping) which also made previous 08/17 patch ("Move sja1105_is_link_local to include/linux") useless and therefore dropped. v2 patchset can be found at: https://lkml.org/lkml/2019/6/2/146 Changes from v2: - Broke previous 09/10 patch (timestamping) into multiple smaller patches. - Every patch in the series compiles. v1 patchset can be found at: https://lkml.org/lkml/2019/5/28/1093 Changes from v1: - Removed the addition of the DSA .can_timestamp callback. - Waiting for meta frames is done completely inside the tagger, and all frames emitted on RX are already partially timestamped. - Added a global data structure for the tagger common to all ports. - Made PTP work with ports in standalone mode, by limiting use of the DMAC-mangling "incl_srcpt" mode only when ports are bridged, aka when the DSA master is already promiscuous and can receive anything. Also changed meta frames to be sent at the 01-80-C2-00-00-0E DMAC. - Made some progress w.r.t. observed negative path delay. Apparently it only appears when the delay mechanism is the delay request-response (end-to-end) one. If peer delay is used (-P), the path delay is positive and appears reasonable for an 1000Base-T link (485 ns in steady state). SJA1105 as PTP slave (OC) with E2E path delay: ptp4l[55.600]: master offset 8 s2 freq +83677 path delay -2390 ptp4l[56.600]: master offset 17 s2 freq +83688 path delay -2391 ptp4l[57.601]: master offset 6 s2 freq +83682 path delay -2391 ptp4l[58.601]: master offset -1 s2 freq +83677 path delay -2391 SJA1105 as PTP slave (OC) with P2P path delay: ptp4l[48.343]: master offset 5 s2 freq +83715 path delay 484 ptp4l[48.468]: master offset -3 s2 freq +83705 path delay 485 ptp4l[48.593]: master offset 0 s2 freq +83708 path delay 485 ptp4l[48.718]: master offset 1 s2 freq +83710 path delay 485 ptp4l[48.844]: master offset 1 s2 freq +83710 path delay 485 ptp4l[48.969]: master offset -5 s2 freq +83702 path delay 485 ptp4l[49.094]: master offset 3 s2 freq +83712 path delay 485 ptp4l[49.219]: master offset 4 s2 freq +83714 path delay 485 ptp4l[49.344]: master offset -5 s2 freq +83702 path delay 485 ptp4l[49.469]: master offset 3 s2 freq +83713 path delay 487 ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
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