Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 122 insertions, 0 deletions

diff --git a/Documentation/networking/devlink/devlink-linecard.rst b/Documentation/networking/devlink/devlink-linecard.rst
new file mode 100644
index 000000000..6c0b8928b
--- /dev/null
+++ b/Documentation/networking/devlink/devlink-linecard.rst
@@ -0,0 +1,122 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=================
+Devlink Line card
+=================
+
+Background
+==========
+
+The ``devlink-linecard`` mechanism is targeted for manipulation of
+line cards that serve as a detachable PHY modules for modular switch
+system. Following operations are provided:
+
+  * Get a list of supported line card types.
+  * Provision of a slot with specific line card type.
+  * Get and monitor of line card state and its change.
+
+Line card according to the type may contain one or more gearboxes
+to mux the lanes with certain speed to multiple ports with lanes
+of different speed. Line card ensures N:M mapping between
+the switch ASIC modules and physical front panel ports.
+
+Overview
+========
+
+Each line card devlink object is created by device driver,
+according to the physical line card slots available on the device.
+
+Similar to splitter cable, where the device might have no way
+of detection of the splitter cable geometry, the device
+might not have a way to detect line card type. For that devices,
+concept of provisioning is introduced. It allows the user to:
+
+  * Provision a line card slot with certain line card type
+
+    - Device driver would instruct the ASIC to prepare all
+      resources accordingly. The device driver would
+      create all instances, namely devlink port and netdevices
+      that reside on the line card, according to the line card type
+  * Manipulate of line card entities even without line card
+    being physically connected or powered-up
+  * Setup splitter cable on line card ports
+
+    - As on the ordinary ports, user may provision a splitter
+      cable of a certain type, without the need to
+      be physically connected to the port
+  * Configure devlink ports and netdevices
+
+Netdevice carrier is decided as follows:
+
+  * Line card is not inserted or powered-down
+
+    - The carrier is always down
+  * Line card is inserted and powered up
+
+    - The carrier is decided as for ordinary port netdevice
+
+Line card state
+===============
+
+The ``devlink-linecard`` mechanism supports the following line card states:
+
+  * ``unprovisioned``: Line card is not provisioned on the slot.
+  * ``unprovisioning``: Line card slot is currently being unprovisioned.
+  * ``provisioning``: Line card slot is currently in a process of being provisioned
+    with a line card type.
+  * ``provisioning_failed``: Provisioning was not successful.
+  * ``provisioned``: Line card slot is provisioned with a type.
+  * ``active``: Line card is powered-up and active.
+
+The following diagram provides a general overview of ``devlink-linecard``
+state transitions::
+
+                                          +-------------------------+
+                                          |                         |
+       +---------------------------------->      unprovisioned      |
+       |                                  |                         |
+       |                                  +--------|-------^--------+
+       |                                           |       |
+       |                                           |       |
+       |                                  +--------v-------|--------+
+       |                                  |                         |
+       |                                  |       provisioning      |
+       |                                  |                         |
+       |                                  +------------|------------+
+       |                                               |
+       |                 +-----------------------------+
+       |                 |                             |
+       |    +------------v------------+   +------------v------------+   +-------------------------+
+       |    |                         |   |                         ---->                         |
+       +-----   provisioning_failed   |   |       provisioned       |   |         active          |
+       |    |                         |   |                         <----                         |
+       |    +------------^------------+   +------------|------------+   +-------------------------+
+       |                 |                             |
+       |                 |                             |
+       |                 |                +------------v------------+
+       |                 |                |                         |
+       |                 |                |     unprovisioning      |
+       |                 |                |                         |
+       |                 |                +------------|------------+
+       |                 |                             |
+       |                 +-----------------------------+
+       |                                               |
+       +-----------------------------------------------+
+
+
+Example usage
+=============
+
+.. code:: shell
+
+    $ devlink lc show [ DEV [ lc LC_INDEX ] ]
+    $ devlink lc set DEV lc LC_INDEX [ { type LC_TYPE | notype } ]
+
+    # Show current line card configuration and status for all slots:
+    $ devlink lc
+
+    # Set slot 8 to be provisioned with type "16x100G":
+    $ devlink lc set pci/0000:01:00.0 lc 8 type 16x100G
+
+    # Set slot 8 to be unprovisioned:
+    $ devlink lc set pci/0000:01:00.0 lc 8 notype