X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fnics%2Fmlx5.rst;h=b0614ae335668b2ae8bd7f97a90f2f26a816ccbd;hb=1736219b3c5737c943620c22121b361e35b18d0d;hp=00427b00e614670f18c10f863c425231118ed665;hpb=5522da6b201b3db935e2f1e2b107267203288fc2;p=dpdk.git

diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index 00427b00e6..b0614ae335 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -253,6 +253,14 @@ Limitations
   reported via device xstats to assist applications to detect the
   time-related problems.
 
+  The timestamp upper "too-distant-future" limit
+  at the moment of invoking the Tx burst routine
+  can be estimated as ``tx_pp`` option (in nanoseconds) multiplied by 2^23.
+  Please note, for the testpmd txonly mode,
+  the limit is deduced from the expression::
+
+        (n_tx_descriptors / burst_size + 1) * inter_burst_gap
+
   There is no any packet reordering according timestamps is supposed,
   neither within packet burst, nor between packets, it is an entirely
   application responsibility to generate packets and its timestamps
@@ -297,6 +305,12 @@ Limitations
 
     Other TCP packets (e.g. with MPLS label) received on Rx queue with LRO enabled, will be received with bad checksum.
 
+- CRC:
+
+  - ``DEV_RX_OFFLOAD_KEEP_CRC`` cannot be supported with decapsulation
+    for some NICs (such as ConnectX-6 Dx and BlueField 2).
+    The capability bit ``scatter_fcs_w_decap_disable`` shows NIC support.
+
 Statistics
 ----------
 
@@ -923,6 +937,15 @@ Driver options
 
   By default, the PMD will set this value to 0.
 
+- ``decap_en`` parameter [int]
+
+  Some devices do not support FCS (frame checksum) scattering for
+  tunnel-decapsulated packets.
+  If set to 0, this option forces the FCS feature and rejects tunnel
+  decapsulation in the flow engine for such devices.
+
+  By default, the PMD will set this value to 1.
+
 .. _mlx5_firmware_config:
 
 Firmware configuration
@@ -1224,8 +1247,8 @@ Quick Start Guide on OFED/EN
 
         echo [num_vfs] > /sys/class/infiniband/mlx5_0/device/sriov_numvfs
 
-6. Compile DPDK and you are ready to go. See instructions on
-   :ref:`Development Kit Build System <Development_Kit_Build_System>`
+6. Install DPDK and you are ready to go.
+   See :doc:`compilation instructions <../linux_gsg/build_dpdk>`.
 
 Enable switchdev mode
 ---------------------