Added documentation for devlink port and port function related commands.
Signed-off-by: Parav Pandit <pa...@nvidia.com>
Reviewed-by: Jiri Pirko <j...@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.kel...@intel.com>
---
Changelog:
v2->v3:
- rephased many lines
- first paragraph now describe devlink port
- instead of saying PCI device/function, using PCI function every
where
- changed 'physical link layer' to 'link layer'
- made devlink port type description more clear
- made devlink port flavour description more clear
- moved devlink port type table after port flavour
- added description for the example diagram
- describe CPU port that its linked to DSA
- made devlink port description for eswitch port more clear
v1->v2:
- Removed duplicate table entries for DEVLINK_PORT_FLAVOUR_VIRTUAL.
- replaced 'consist of' to 'consisting'
- changed 'can be' to 'can be of'
---
.../networking/devlink/devlink-port.rst | 111 ++++++++++++++++++
Documentation/networking/devlink/index.rst | 1 +
2 files changed, 112 insertions(+)
create mode 100644 Documentation/networking/devlink/devlink-port.rst
diff --git a/Documentation/networking/devlink/devlink-port.rst
b/Documentation/networking/devlink/devlink-port.rst
new file mode 100644
index 000000000000..8407bbe9ce88
--- /dev/null
+++ b/Documentation/networking/devlink/devlink-port.rst
@@ -0,0 +1,111 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+============
+Devlink Port
+============
+
+``devlink-port`` is a port that exist on the device. A devlink port can
+be of one among many flavours. A devlink port flavour along with port
+attributes describe what a port represents.
+
+A device driver who intents to publish a devlink port, sets the
+devlink port attributes and registers the devlink port.
+
+Devlink port flavours are described below.
+
+.. list-table:: List of devlink port flavours
+ :widths: 33 90
+
+ * - Flavour
+ - Description
+ * - ``DEVLINK_PORT_FLAVOUR_PHYSICAL``
+ - Any kind of physical networking port. This can be a eswitch physical
+ port or any other physical port on the device.
+ * - ``DEVLINK_PORT_FLAVOUR_DSA``
+ - This indicates a DSA interconnect port.
+ * - ``DEVLINK_PORT_FLAVOUR_CPU``
+ - This indicates a CPU port applicable only to DSA.
+ * - ``DEVLINK_PORT_FLAVOUR_PCI_PF``
+ - This indicates an eswitch port representing a networking port of
+ PCI physical function (PF).
+ * - ``DEVLINK_PORT_FLAVOUR_PCI_VF``
+ - This indicates an eswitch port representing a networking port of
+ PCI virtual function (VF).
+ * - ``DEVLINK_PORT_FLAVOUR_VIRTUAL``
+ - This indicates a virtual port for the virtual PCI device such as PCI VF.
+
+A devlink port types are described below.
+
+.. list-table:: List of devlink port types
+ :widths: 23 90
+
+ * - Type
+ - Description
+ * - ``DEVLINK_PORT_TYPE_ETH``
+ - Driver should set this port type when a link layer of the port is
Ethernet.
+ * - ``DEVLINK_PORT_TYPE_IB``
+ - Driver should set this port type when a link layer of the port is
InfiniBand.
+ * - ``DEVLINK_PORT_TYPE_AUTO``
+ - This type is indicated by the user when user prefers to set the port
type
+ to be automatically detected by the device driver.
+
+A controller consist of one or more PCI functions. Such PCI function can have
one
+or more networking ports. A networking port of such PCI function is represented
+by the eswitch devlink port. A devlink instance holds ports of two types of
+controllers.
+
+(1) controller discovered on same system where eswitch resides:
+This is the case where PCI PF/VF of a controller and devlink eswitch
+instance both are located on a single system.
+
+(2) controller located on external host system.
+This is the case where a controller is located in one system and its
+devlink eswitch ports are located in a different system. Such controller
+is called external controller.
+
+An example view of two controller systems::
+
+In this example a controller which contains the eswitch is local controller
+with controller number = 0. The second is a external controller having
+controller number = 1. Eswitch devlink instance has representor devlink
+ports for the PCI functions of both the controllers.
+
+ ---------------------------------------------------------
+ | |
+ | --------- --------- ------- ------- |
+ ----------- | | vf(s) | | sf(s) | |vf(s)| |sf(s)| |
+ | server | | ------- ----/---- ---/----- ------- ---/--- ---/--- |
+ | pci rc |=== | pf0 |______/________/ | pf1 |___/_______/ |
+ | connect | | ------- ------- |
+ ----------- | | controller_num=1 (no eswitch) |
+ ------|--------------------------------------------------
+ (internal wire)
+ |
+ ---------------------------------------------------------
+ | devlink eswitch ports and reps |
+ | ----------------------------------------------------- |
+ | |ctrl-0 | ctrl-0 | ctrl-0 | ctrl-0 | ctrl-0 |ctrl-0 | |
+ | |pf0 | pf0vfN | pf0sfN | pf1 | pf1vfN |pf1sfN | |
+ | ----------------------------------------------------- |
+ | |ctrl-1 | ctrl-1 | ctrl-1 | ctrl-1 | ctrl-1 |ctrl-1 | |
+ | |pf0 | pf0vfN | pf0sfN | pf1 | pf1vfN |pf1sfN | |
+ | ----------------------------------------------------- |
+ | |
+ | |
+ | --------- --------- ------- ------- |
+ | | vf(s) | | sf(s) | |vf(s)| |sf(s)| |
+ | ------- ----/---- ---/----- ------- ---/--- ---/--- |
+ | | pf0 |______/________/ | pf1 |___/_______/ |
+ | ------- ------- |
+ | |
+ | local controller_num=0 (eswitch) |
+ ---------------------------------------------------------
+
+Port function configuration
+===========================
+
+When a port flavor is ``DEVLINK_PORT_FLAVOUR_PCI_PF`` or
+``DEVLINK_PORT_FLAVOUR_PCI_VF``, it represents the networking port of a
+PCI function. A user can configure the port function attributes before
+enumerating the function. For example user may set the hardware address of
+the function represented by the devlink port function.
diff --git a/Documentation/networking/devlink/index.rst
b/Documentation/networking/devlink/index.rst
index d82874760ae2..aab79667f97b 100644
--- a/Documentation/networking/devlink/index.rst
+++ b/Documentation/networking/devlink/index.rst
@@ -18,6 +18,7 @@ general.
devlink-info
devlink-flash
devlink-params
+ devlink-port
devlink-region
devlink-resource
devlink-reload
--
2.26.2
