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+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+netdevsim devlink support
+=========================
+
+This document describes the ``devlink`` features supported by the
+``netdevsim`` device driver.
+
+Parameters
+==========
+
+.. list-table:: Generic parameters implemented
+
+   * - Name
+     - Mode
+   * - ``max_macs``
+     - driverinit
+
+The ``netdevsim`` driver also implements the following driver-specific
+parameters.
+
+.. list-table:: Driver-specific parameters implemented
+   :widths: 5 5 5 85
+
+   * - Name
+     - Type
+     - Mode
+     - Description
+   * - ``test1``
+     - Boolean
+     - driverinit
+     - Test parameter used to show how a driver-specific devlink parameter
+       can be implemented.
+
+The ``netdevsim`` driver supports reloading via ``DEVLINK_CMD_RELOAD``
+
+Regions
+=======
+
+The ``netdevsim`` driver exposes a ``dummy`` region as an example of how the
+devlink-region interfaces work. A snapshot is taken whenever the
+``take_snapshot`` debugfs file is written to.
+
+Resources
+=========
+
+The ``netdevsim`` driver exposes resources to control the number of FIB
+entries, FIB rule entries and nexthops that the driver will allow.
+
+.. code:: shell
+
+    $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib size 96
+    $ devlink resource set netdevsim/netdevsim0 path /IPv4/fib-rules size 16
+    $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib size 64
+    $ devlink resource set netdevsim/netdevsim0 path /IPv6/fib-rules size 16
+    $ devlink resource set netdevsim/netdevsim0 path /nexthops size 16
+    $ devlink dev reload netdevsim/netdevsim0
+
+Rate objects
+============
+
+The ``netdevsim`` driver supports rate objects management, which includes:
+
+- registerging/unregistering leaf rate objects per VF devlink port;
+- creation/deletion node rate objects;
+- setting tx_share and tx_max rate values for any rate object type;
+- setting parent node for any rate object type.
+
+Rate nodes and their parameters are exposed in ``netdevsim`` debugfs in RO mode.
+For example created rate node with name ``some_group``:
+
+.. code:: shell
+
+    $ ls /sys/kernel/debug/netdevsim/netdevsim0/rate_groups/some_group
+    rate_parent  tx_max  tx_share
+
+Same parameters are exposed for leaf objects in corresponding ports directories.
+For ex.:
+
+.. code:: shell
+
+    $ ls /sys/kernel/debug/netdevsim/netdevsim0/ports/1
+    dev  ethtool  rate_parent  tx_max  tx_share
+
+Driver-specific Traps
+=====================
+
+.. list-table:: List of Driver-specific Traps Registered by ``netdevsim``
+   :widths: 5 5 90
+
+   * - Name
+     - Type
+     - Description
+   * - ``fid_miss``
+     - ``exception``
+     - When a packet enters the device it is classified to a filtering
+       identifier (FID) based on the ingress port and VLAN. This trap is used
+       to trap packets for which a FID could not be found