| Linux Devlink Documentation |
| =========================== |
| |
| devlink is an API to expose device information and resources not directly |
| related to any device class, such as chip-wide/switch-ASIC-wide configuration. |
| |
| Locking |
| ------- |
| |
| Driver facing APIs are currently transitioning to allow more explicit |
| locking. Drivers can use the existing ``devlink_*`` set of APIs, or |
| new APIs prefixed by ``devl_*``. The older APIs handle all the locking |
| in devlink core, but don't allow registration of most sub-objects once |
| the main devlink object is itself registered. The newer ``devl_*`` APIs assume |
| the devlink instance lock is already held. Drivers can take the instance |
| lock by calling ``devl_lock()``. It is also held all callbacks of devlink |
| netlink commands. |
| |
| Drivers are encouraged to use the devlink instance lock for their own needs. |
| |
| Drivers need to be cautious when taking devlink instance lock and |
| taking RTNL lock at the same time. Devlink instance lock needs to be taken |
| first, only after that RTNL lock could be taken. |
| |
| Nested instances |
| ---------------- |
| |
| Some objects, like linecards or port functions, could have another |
| devlink instances created underneath. In that case, drivers should make |
| sure to respect following rules: |
| |
| - Lock ordering should be maintained. If driver needs to take instance |
| lock of both nested and parent instances at the same time, devlink |
| instance lock of the parent instance should be taken first, only then |
| instance lock of the nested instance could be taken. |
| - Driver should use object-specific helpers to setup the |
| nested relationship: |
| |
| - ``devl_nested_devlink_set()`` - called to setup devlink -> nested |
| devlink relationship (could be user for multiple nested instances. |
| - ``devl_port_fn_devlink_set()`` - called to setup port function -> |
| nested devlink relationship. |
| - ``devlink_linecard_nested_dl_set()`` - called to setup linecard -> |
| nested devlink relationship. |
| |
| The nested devlink info is exposed to the userspace over object-specific |
| attributes of devlink netlink. |
| |
| Interface documentation |
| ----------------------- |
| |
| The following pages describe various interfaces available through devlink in |
| general. |
| |
| .. toctree:: |
| :maxdepth: 1 |
| |
| devlink-dpipe |
| devlink-health |
| devlink-info |
| devlink-flash |
| devlink-params |
| devlink-port |
| devlink-region |
| devlink-resource |
| devlink-reload |
| devlink-selftests |
| devlink-trap |
| devlink-linecard |
| |
| Driver-specific documentation |
| ----------------------------- |
| |
| Each driver that implements ``devlink`` is expected to document what |
| parameters, info versions, and other features it supports. |
| |
| .. toctree:: |
| :maxdepth: 1 |
| |
| bnxt |
| etas_es58x |
| hns3 |
| i40e |
| ionic |
| ice |
| mlx4 |
| mlx5 |
| mlxsw |
| mv88e6xxx |
| netdevsim |
| nfp |
| qed |
| ti-cpsw-switch |
| am65-nuss-cpsw-switch |
| prestera |
| iosm |
| octeontx2 |
| sfc |
