X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fnics%2Fnfb.rst;h=e987f331048ce176603f622f5b5619e5282358e7;hb=413c75c33c402a3170b8311bdc9afb7bded29207;hp=3d93904040d7969da51451c2af8c713cfcce124b;hpb=f37c57a1a33027e8e3a686107f3b8feb13c132ba;p=dpdk.git

diff --git a/doc/guides/nics/nfb.rst b/doc/guides/nics/nfb.rst
index 3d93904040..e987f33104 100644
--- a/doc/guides/nics/nfb.rst
+++ b/doc/guides/nics/nfb.rst
@@ -16,13 +16,6 @@ and used technology
 (`Netcope Development Kit <http://www.netcope.com/en/products/fpga-development-kit>`_)
 can be found on the `Netcope Technologies website <http://www.netcope.com/>`_.
 
-.. note::
-
-   This driver has external dependencies.
-   Therefore it is disabled in default configuration files.
-   It can be enabled by setting ``CONFIG_RTE_LIBRTE_NFB_PMD=y``
-   and recompiling.
-
 .. note::
 
    Currently the driver is supported only on x86_64 architectures.
@@ -62,12 +55,24 @@ The minimum version of the provided packages:
 Configuration
 -------------
 
-These configuration options can be modified before compilation in the
-``.config`` file:
+Timestamps
+
+The PMD supports hardware timestamps of frame receipt on physical network interface. In order to use
+the timestamps, the hardware timestamping unit must be enabled (follow the documentation of the NFB
+products) and the device argument `timestamp=1` must be used.
+
+.. code-block:: console
+
+    ./<build_dir>/app/dpdk-testpmd -a b3:00.0,timestamp=1 <other EAL params> -- <testpmd params>
+
+When the timestamps are enabled with the *devarg*, a timestamp validity flag is set in the MBUFs
+containing received frames and timestamp is inserted into the `rte_mbuf` struct.
 
-*  ``CONFIG_RTE_LIBRTE_NFB_PMD`` default value: **n**
+The timestamp is an `uint64_t` field. Its lower 32 bits represent *seconds* portion of the timestamp
+(number of seconds elapsed since 1.1.1970 00:00:00 UTC) and its higher 32 bits represent
+*nanosecond* portion of the timestamp (number of nanoseconds elapsed since the beginning of the
+second in the *seconds* portion.
 
-   Value **y** enables compilation of nfb PMD.
 
 Using the NFB PMD
 ----------------------
@@ -113,7 +118,7 @@ transmit queue:
 
 .. code-block:: console
 
-   $RTE_TARGET/app/testpmd -l 0-3 -n 2 \
+   ./<build_dir>/app/dpdk-testpmd -l 0-3 -n 2 \
    -- --port-topology=chained --rxq=2 --txq=2 --nb-cores=2 -i -a
 
 Example output: