Merge branch 'upstream-16.11-stable' into 16.11.x

[deb_dpdk.git] / doc / guides / nics / i40e.rst

diff --git a/doc/guides/nics/i40e.rst b/doc/guides/nics/i40e.rst
index 5780268..556b55f 100644 (file)
--- a/doc/guides/nics/i40e.rst
+++ b/doc/guides/nics/i40e.rst
@@ -130,6 +130,21 @@ Please note that enabling debugging options may affect system performance.
   Interrupt Throttling interval.
 
 
+Runtime Config Options
+~~~~~~~~~~~~~~~~~~~~~~
+
+- ``Support multiple driver`` (default ``disable``)
+
+  There was a multiple driver support issue during use of 700 series Ethernet
+  Adapter with both Linux kernel and DPDK PMD. To fix this issue, ``devargs``
+  parameter ``support-multi-driver`` is introduced, for example::
+
+    -w 84:00.0,support-multi-driver=1
+
+  With the above configuration, DPDK PMD will not change global registers, and
+  will switch PF interrupt from IntN to Int0 to avoid interrupt conflict between
+  DPDK and Linux Kernel.
+
 Driver Compilation
 ~~~~~~~~~~~~~~~~~~
 
@@ -459,3 +474,15 @@ Receive packets with Ethertype 0x88A8
 
 Due to the FW limitation, PF can receive packets with Ethertype 0x88A8
 only when floating VEB is disabled.
+
+Global configuration warning
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+I40E PMD will set some global registers to enable some function or set some
+configure. Then when using different ports of the same NIC with Linux kernel
+and DPDK, the port with Linux kernel will be impacted by the port with DPDK.
+For example, register I40E_GL_SWT_L2TAGCTRL is used to control L2 tag, i40e
+PMD uses I40E_GL_SWT_L2TAGCTRL to set vlan TPID. If setting TPID in port A
+with DPDK, then the configuration will also impact port B in the NIC with
+kernel driver, which don't want to use the TPID.
+So PMD reports warning to clarify what is changed by writing global register.