Merge branch 'mlxsw-line-card'

Ido Schimmel says:

====================
mlxsw: Introduce line card support for modular switch

Jiri says:

This patchset introduces support for modular switch systems and also
introduces mlxsw support for NVIDIA Mellanox SN4800 modular switch.
It contains 8 slots to accommodate line cards - replaceable PHY modules
which may contain gearboxes.
Currently supported line card:
16X 100GbE (QSFP28)
Other line cards that are going to be supported:
8X 200GbE (QSFP56)
4X 400GbE (QSFP-DD)
There may be other types of line cards added in the future.

To be consistent with the port split configuration (splitter cabels),
the line card entities are treated in the similar way. The nature of
a line card is not "a pluggable device", but "a pluggable PHY module".

A concept of "provisioning" is introduced. The user may "provision"
certain slot with a line card type. Driver then creates all instances
(devlink ports, netdevices, etc) related to this line card type. It does
not matter if the line card is plugged-in at the time. User is able to
configure netdevices, devlink ports, setup port splitters, etc. From the
perspective of the switch ASIC, all is present and can be configured.

The carrier of netdevices stays down if the line card is not plugged-in.
Once the line card is inserted and activated, the carrier of
the related netdevices is then reflecting the physical line state,
same as for an ordinary fixed port.

Once user does not want to use the line card related instances
anymore, he can "unprovision" the slot. Driver then removes the
instances.

Patches 1-4 are extending devlink driver API and UAPI in order to
register, show, dump, provision and activate the line card.
Patches 5-17 are implementing the introduced API in mlxsw.
The last patch adds a selftest for mlxsw line cards.

Example:
$ devlink port # No ports are listed
$ devlink lc
pci/0000:01:00.0:
  lc 1 state unprovisioned
    supported_types:
       16x100G
  lc 2 state unprovisioned
    supported_types:
       16x100G
  lc 3 state unprovisioned
    supported_types:
       16x100G
  lc 4 state unprovisioned
    supported_types:
       16x100G
  lc 5 state unprovisioned
    supported_types:
       16x100G
  lc 6 state unprovisioned
    supported_types:
       16x100G
  lc 7 state unprovisioned
    supported_types:
       16x100G
  lc 8 state unprovisioned
    supported_types:
       16x100G

Note that driver exposes list supported line card types. Currently
there is only one: "16x100G".

To provision the slot #8:

$ devlink lc set pci/0000:01:00.0 lc 8 type 16x100G
$ devlink lc show pci/0000:01:00.0 lc 8
pci/0000:01:00.0:
  lc 8 state active type 16x100G
    supported_types:
       16x100G
$ devlink port
pci/0000:01:00.0/0: type notset flavour cpu port 0 splittable false
pci/0000:01:00.0/53: type eth netdev enp1s0nl8p1 flavour physical lc 8 port 1 splittable true lanes 4
pci/0000:01:00.0/54: type eth netdev enp1s0nl8p2 flavour physical lc 8 port 2 splittable true lanes 4
pci/0000:01:00.0/55: type eth netdev enp1s0nl8p3 flavour physical lc 8 port 3 splittable true lanes 4
pci/0000:01:00.0/56: type eth netdev enp1s0nl8p4 flavour physical lc 8 port 4 splittable true lanes 4
pci/0000:01:00.0/57: type eth netdev enp1s0nl8p5 flavour physical lc 8 port 5 splittable true lanes 4
pci/0000:01:00.0/58: type eth netdev enp1s0nl8p6 flavour physical lc 8 port 6 splittable true lanes 4
pci/0000:01:00.0/59: type eth netdev enp1s0nl8p7 flavour physical lc 8 port 7 splittable true lanes 4
pci/0000:01:00.0/60: type eth netdev enp1s0nl8p8 flavour physical lc 8 port 8 splittable true lanes 4
pci/0000:01:00.0/61: type eth netdev enp1s0nl8p9 flavour physical lc 8 port 9 splittable true lanes 4
pci/0000:01:00.0/62: type eth netdev enp1s0nl8p10 flavour physical lc 8 port 10 splittable true lanes 4
pci/0000:01:00.0/63: type eth netdev enp1s0nl8p11 flavour physical lc 8 port 11 splittable true lanes 4
pci/0000:01:00.0/64: type eth netdev enp1s0nl8p12 flavour physical lc 8 port 12 splittable true lanes 4
pci/0000:01:00.0/125: type eth netdev enp1s0nl8p13 flavour physical lc 8 port 13 splittable true lanes 4
pci/0000:01:00.0/126: type eth netdev enp1s0nl8p14 flavour physical lc 8 port 14 splittable true lanes 4
pci/0000:01:00.0/127: type eth netdev enp1s0nl8p15 flavour physical lc 8 port 15 splittable true lanes 4
pci/0000:01:00.0/128: type eth netdev enp1s0nl8p16 flavour physical lc 8 port 16 splittable true lanes 4

To uprovision the slot #8:

$ devlink lc set pci/0000:01:00.0 lc 8 notype
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 123 insertions, 0 deletions

diff --git a/Documentation/networking/devlink/devlink-linecard.rst b/Documentation/networking/devlink/devlink-linecard.rst
new file mode 100644
index 000000000000..6c0b8928bc13
--- /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
diff --git a/Documentation/networking/devlink/index.rst b/Documentation/networking/devlink/index.rst
index c17cdb079611..850715512293 100644
--- a/Documentation/networking/devlink/index.rst
+++ b/Documentation/networking/devlink/index.rst
@@ -39,6 +39,7 @@ general.
    devlink-resource
    devlink-reload
    devlink-trap
+   devlink-linecard
 
 Driver-specific documentation
 -----------------------------