On Tue, Oct 28, 2025 at 02:07:58AM -0400, Soumyadeep Hore wrote: > Updated the IDPF Documentation with PTP feature. > > Signed-off-by: Soumyadeep Hore <[email protected]> > --- > doc/guides/nics/idpf.rst | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/doc/guides/nics/idpf.rst b/doc/guides/nics/idpf.rst > index b99cc18188..e76632904b 100644 > --- a/doc/guides/nics/idpf.rst > +++ b/doc/guides/nics/idpf.rst > @@ -109,3 +109,19 @@ The paths are chosen based on 2 conditions: > A value "P" means the offload feature is not supported by vector path. > If any not supported features are used, idpf vector PMD is disabled > and the scalar paths are chosen. > + > +Time Synchronisation > +~~~~~~~~~~~~~~~~~~~~ > + > +The system operator can run a PTP (Precision Time Protocol) client > application > +to synchronise the time on the network card in ACC > +(and optionally the time on the system) to the PTP master. > + > +IDPF PMD supports PTP client applications that use the DPDK IEEE 1588 API > +to communicate with the PTP master clock. > +Note that PTP client application needs to run on PF in ACC > +and add the ``--force-max-simd-bitwidth=64`` startup parameter to disable > vector mode. > + > +.. code-block:: console > + > + examples/dpdk-ptpclient -l 0-3 -n 3 -a 0000:ec:00.1 > --force-max-simd-bitwidth=64 -- -T 1 -p 0x1 -c 1
Why is force-max-simd-bitwidth necessary? When using a feature not supported by the vector driver path, the driver itself must be the one which selects a scalar path. That task cannot fall to the user, or require the user to know that he needs to select a scalar path. /Bruce > -- > 2.47.1 >
