| Message ID | 20201215090358.240365-14-saeed@kernel.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Add mlx5 subfunction support | expand |
On Tue, 15 Dec 2020 01:03:56 -0800 Saeed Mahameed wrote: > +PCI controllers > +--------------- > +In most cases a PCI device has only one controller. A controller consists of > +potentially multiple physical and virtual functions. Such PCI function consists > +of one or more ports. s/Such// you say consists in two consecutive sentences. > This port of the function is represented by the devlink eswitch port. "This port of the function"? Why not just "Each port"? > +A PCI Device connected to multiple CPUs or multiple PCI root complexes or Why is device capitalized all of the sudden? > +SmartNIC, however, may have multiple controllers. For a device with multiple a SmartNIC or SmartNICs > +controllers, each controller is distinguished by a unique controller number. > +An eswitch on the PCI device support ports of multiple controllers. eswitch is on a PCI device? > +An example view of a system with two 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 | | > + | ----------------------------------------------------- | > + | | > + | | > + ----------- | --------- --------- ------- ------- | > + | smartNIC| | | vf(s) | | sf(s) | |vf(s)| |sf(s)| | > + | pci rc |==| ------- ----/---- ---/----- ------- ---/--- ---/--- | > + | connect | | | pf0 |______/________/ | pf1 |___/_______/ | > + ----------- | ------- ------- | > + | | > + | local controller_num=0 (eswitch) | > + --------------------------------------------------------- > + > +In above example, external controller (identified by controller number = 1) > +doesn't have eswitch. Local controller (identified by controller number = 0) > +has the eswitch. Devlink instance on local controller has eswitch devlink > +ports representing ports for both the controllers. > + > +Port function configuration > +=========================== > + > +A user can configure the port function attribute before enumerating the s/A user/User/ /port function attribute/$something_meaningful/ > +PCI function. Usually it means, user should configure port function attribute attributes, plural > +before a bus specific device for the function is created. However, when > +SRIOV is enabled, virtual function devices are created on the PCI bus. > +Hence, function attribute should be configured before binding virtual > +function device to the driver. > + > +User may set the hardware address of the function represented by the devlink > +port function. For Ethernet port function this means a MAC address.
> From: Jakub Kicinski <kuba@kernel.org> > Sent: Wednesday, December 16, 2020 6:28 AM > > On Tue, 15 Dec 2020 01:03:56 -0800 Saeed Mahameed wrote: > > +PCI controllers > > +--------------- > > +In most cases a PCI device has only one controller. A controller > > +consists of potentially multiple physical and virtual functions. Such > > +PCI function consists of one or more ports. > > s/Such// > Ack. > you say consists in two consecutive sentences. > > > This port of the function is represented by the devlink eswitch port. > First sentence describe controller. Second sentence describe function. So what is wrong in that? > "This port of the function"? Why not just "Each port"? > That's fine too. Will simplify. > > +A PCI Device connected to multiple CPUs or multiple PCI root > > +complexes or > > Why is device capitalized all of the sudden? > Will fix. > > +SmartNIC, however, may have multiple controllers. For a device with > > +multiple > > a SmartNIC or SmartNICs > > > +controllers, each controller is distinguished by a unique controller > number. > > +An eswitch on the PCI device support ports of multiple controllers. > > eswitch is on a PCI device? > Will change. > > +An example view of a system with two 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 | | > > + | ----------------------------------------------------- | > > + | | > > + | | > > + ----------- | --------- --------- ------- ------- | > > + | smartNIC| | | vf(s) | | sf(s) | |vf(s)| |sf(s)| | > > + | pci rc |==| ------- ----/---- ---/----- ------- ---/--- ---/--- | > > + | connect | | | pf0 |______/________/ | pf1 |___/_______/ | > > + ----------- | ------- ------- | > > + | | > > + | local controller_num=0 (eswitch) | > > + > > + --------------------------------------------------------- > > + > > +In above example, external controller (identified by controller > > +number = 1) doesn't have eswitch. Local controller (identified by > > +controller number = 0) has the eswitch. Devlink instance on local > > +controller has eswitch devlink ports representing ports for both the > controllers. > > + > > +Port function configuration > > +=========================== > > + > > +A user can configure the port function attribute before enumerating > > +the > > s/A user/User/ > > /port function attribute/$something_meaningful/ > May be just say function attribute? > > +PCI function. Usually it means, user should configure port function > > +attribute > > attributes, plural > Yes, but at present there is only one i.e. mac address, so didn't use plural.
diff --git a/Documentation/networking/devlink/devlink-port.rst b/Documentation/networking/devlink/devlink-port.rst new file mode 100644 index 000000000000..4c910dbb01ca --- /dev/null +++ b/Documentation/networking/devlink/devlink-port.rst @@ -0,0 +1,118 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. _devlink_port: + +============ +Devlink Port +============ + +``devlink-port`` is a port that exists on the device. It has a logically +separate ingress/egress point of the device. A devlink port can be any one +of many flavours. A devlink port flavour along with port attributes +describe what a port represents. + +A device driver that intends 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 port. This can be an 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 port of PCI + physical function (PF). + * - ``DEVLINK_PORT_FLAVOUR_PCI_VF`` + - This indicates an eswitch port representing a port of PCI + virtual function (VF). + * - ``DEVLINK_PORT_FLAVOUR_VIRTUAL`` + - This indicates a virtual port for the PCI virtual function. + +Devlink port can have a different type based on the link layer 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 driver should detect the port + type automatically. + +PCI controllers +--------------- +In most cases a PCI device has only one controller. A controller consists of +potentially multiple physical and virtual functions. Such PCI function consists +of one or more ports. This port of the function is represented by the devlink +eswitch port. + +A PCI Device connected to multiple CPUs or multiple PCI root complexes or +SmartNIC, however, may have multiple controllers. For a device with multiple +controllers, each controller is distinguished by a unique controller number. +An eswitch on the PCI device support ports of multiple controllers. + +An example view of a system with two 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 | | + | ----------------------------------------------------- | + | | + | | + ----------- | --------- --------- ------- ------- | + | smartNIC| | | vf(s) | | sf(s) | |vf(s)| |sf(s)| | + | pci rc |==| ------- ----/---- ---/----- ------- ---/--- ---/--- | + | connect | | | pf0 |______/________/ | pf1 |___/_______/ | + ----------- | ------- ------- | + | | + | local controller_num=0 (eswitch) | + --------------------------------------------------------- + +In above example, external controller (identified by controller number = 1) +doesn't have eswitch. Local controller (identified by controller number = 0) +has the eswitch. Devlink instance on local controller has eswitch devlink +ports representing ports for both the controllers. + +Port function configuration +=========================== + +A user can configure the port function attribute before enumerating the +PCI function. Usually it means, user should configure port function attribute +before a bus specific device for the function is created. However, when +SRIOV is enabled, virtual function devices are created on the PCI bus. +Hence, function attribute should be configured before binding virtual +function device to the driver. + +User may set the hardware address of the function represented by the devlink +port function. For Ethernet port function this means a MAC address. 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