On Mon, 30 Nov 2020 22:00:25 +0200 Parav Pandit wrote: > 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>
> +============ > +Devlink Port > +============ > + > +``devlink-port`` provides capability for a driver to expose various > +flavours of ports which exist on device. A devlink port can be of an > +embedded switch (eswitch) present on the device. The wording is a little awkward here. The first paragraph should clarify what object represents. This just says it exposes ports that exist. A better phrasing would be to say that these are ports of an eswitch, in trivial case the only ports will be the physical ports of the card. > +A devlink port can be of 3 diffferent types. "can be of" repeated from the previous line > +.. list-table:: List of devlink port types > + :widths: 23 90 > + > + * - Type > + - Description > + * - ``DEVLINK_PORT_TYPE_ETH`` > + - This type is set for a devlink port when a physical link layer of the > port Is "physical link layer" a thing? I the common names are physical layer and a (data) link layer. I don't think I've seen physical link layer, or would know what it is... > + is Ethernet. > + * - ``DEVLINK_PORT_TYPE_IB`` > + - This type is set for a devlink port when a physical 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. IMO type should be after flavor. Flavor is a higher level attribute, only physical ports have a type. > +Devlink port can be of few different flavours described below. > + > +.. list-table:: List of devlink port flavours > + :widths: 33 90 > + > + * - Flavour > + - Description > + * - ``DEVLINK_PORT_FLAVOUR_PHYSICAL`` > + - Any kind of port which is physically facing the user. This can be Hm. Not a great phrasing :( It faces a physical networking layer. To me PCIe faces the user. > + a eswitch physical port or any other physical port on the device. > + * - ``DEVLINK_PORT_FLAVOUR_CPU`` > + - This indicates a CPU port. You need to mention this is a DSA-only thing. > + * - ``DEVLINK_PORT_FLAVOUR_DSA`` > + - This indicates a interconnect port in a distributed switch > architecture. (DSA) > + * - ``DEVLINK_PORT_FLAVOUR_PCI_PF`` > + - This indicates an eswitch port representing PCI physical function(PF). > + * - ``DEVLINK_PORT_FLAVOUR_PCI_VF`` > + - This indicates an eswitch port representing PCI virtual function(VF). > + * - ``DEVLINK_PORT_FLAVOUR_VIRTUAL`` > + - This indicates a virtual port facing the user. No idea what that means from the description. > +A devlink port may be for a controller consisting one or more PCI device(s). Port can have multiple PCI devices? > +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. > + > +An example view of two controller systems:: > + > + --------------------------------------------------------- > + | | > + | --------- --------- ------- ------- | > + ----------- | | 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 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. > 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
