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Diffstat (limited to 'Documentation/networking/timestamping.rst')
-rw-r--r-- | Documentation/networking/timestamping.rst | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/Documentation/networking/timestamping.rst b/Documentation/networking/timestamping.rst index 61ef9da10e28..7aabead90648 100644 --- a/Documentation/networking/timestamping.rst +++ b/Documentation/networking/timestamping.rst @@ -140,6 +140,14 @@ SOF_TIMESTAMPING_TX_ACK: cumulative acknowledgment. The mechanism ignores SACK and FACK. This flag can be enabled via both socket options and control messages. +SOF_TIMESTAMPING_TX_COMPLETION: + Request tx timestamps on packet tx completion. The completion + timestamp is generated by the kernel when it receives packet a + completion report from the hardware. Hardware may report multiple + packets at once, and completion timestamps reflect the timing of the + report and not actual tx time. This flag can be enabled via both + socket options and control messages. + 1.3.2 Timestamp Reporting ^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -803,11 +811,9 @@ Documentation/devicetree/bindings/ptp/timestamper.txt for more details. 3.2.4 Other caveats for MAC drivers ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -Stacked PHCs, especially DSA (but not only) - since that doesn't require any -modification to MAC drivers, so it is more difficult to ensure correctness of -all possible code paths - is that they uncover bugs which were impossible to -trigger before the existence of stacked PTP clocks. One example has to do with -this line of code, already presented earlier:: +The use of stacked PHCs may uncover MAC driver bugs which were impossible to +trigger without them. One example has to do with this line of code, already +presented earlier:: skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; |