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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+ice devlink support
+===================
+
+This document describes the devlink features implemented by the ``ice``
+device driver.
+
+Info versions
+=============
+
+The ``ice`` driver reports the following versions
+
+.. list-table:: devlink info versions implemented
+ :widths: 5 5 5 90
+
+ * - Name
+ - Type
+ - Example
+ - Description
+ * - ``board.id``
+ - fixed
+ - K65390-000
+ - The Product Board Assembly (PBA) identifier of the board.
+ * - ``fw.mgmt``
+ - running
+ - 2.1.7
+ - 3-digit version number of the management firmware running on the
+ Embedded Management Processor of the device. It controls the PHY,
+ link, access to device resources, etc. Intel documentation refers to
+ this as the EMP firmware.
+ * - ``fw.mgmt.api``
+ - running
+ - 1.5.1
+ - 3-digit version number (major.minor.patch) of the API exported over
+ the AdminQ by the management firmware. Used by the driver to
+ identify what commands are supported. Historical versions of the
+ kernel only displayed a 2-digit version number (major.minor).
+ * - ``fw.mgmt.build``
+ - running
+ - 0x305d955f
+ - Unique identifier of the source for the management firmware.
+ * - ``fw.undi``
+ - running
+ - 1.2581.0
+ - Version of the Option ROM containing the UEFI driver. The version is
+ reported in ``major.minor.patch`` format. The major version is
+ incremented whenever a major breaking change occurs, or when the
+ minor version would overflow. The minor version is incremented for
+ non-breaking changes and reset to 1 when the major version is
+ incremented. The patch version is normally 0 but is incremented when
+ a fix is delivered as a patch against an older base Option ROM.
+ * - ``fw.psid.api``
+ - running
+ - 0.80
+ - Version defining the format of the flash contents.
+ * - ``fw.bundle_id``
+ - running
+ - 0x80002ec0
+ - Unique identifier of the firmware image file that was loaded onto
+ the device. Also referred to as the EETRACK identifier of the NVM.
+ * - ``fw.app.name``
+ - running
+ - ICE OS Default Package
+ - The name of the DDP package that is active in the device. The DDP
+ package is loaded by the driver during initialization. Each
+ variation of the DDP package has a unique name.
+ * - ``fw.app``
+ - running
+ - 1.3.1.0
+ - The version of the DDP package that is active in the device. Note
+ that both the name (as reported by ``fw.app.name``) and version are
+ required to uniquely identify the package.
+ * - ``fw.app.bundle_id``
+ - running
+ - 0xc0000001
+ - Unique identifier for the DDP package loaded in the device. Also
+ referred to as the DDP Track ID. Can be used to uniquely identify
+ the specific DDP package.
+ * - ``fw.netlist``
+ - running
+ - 1.1.2000-6.7.0
+ - The version of the netlist module. This module defines the device's
+ Ethernet capabilities and default settings, and is used by the
+ management firmware as part of managing link and device
+ connectivity.
+ * - ``fw.netlist.build``
+ - running
+ - 0xee16ced7
+ - The first 4 bytes of the hash of the netlist module contents.
+
+Flash Update
+============
+
+The ``ice`` driver implements support for flash update using the
+``devlink-flash`` interface. It supports updating the device flash using a
+combined flash image that contains the ``fw.mgmt``, ``fw.undi``, and
+``fw.netlist`` components.
+
+.. list-table:: List of supported overwrite modes
+ :widths: 5 95
+
+ * - Bits
+ - Behavior
+ * - ``DEVLINK_FLASH_OVERWRITE_SETTINGS``
+ - Do not preserve settings stored in the flash components being
+ updated. This includes overwriting the port configuration that
+ determines the number of physical functions the device will
+ initialize with.
+ * - ``DEVLINK_FLASH_OVERWRITE_SETTINGS`` and ``DEVLINK_FLASH_OVERWRITE_IDENTIFIERS``
+ - Do not preserve either settings or identifiers. Overwrite everything
+ in the flash with the contents from the provided image, without
+ performing any preservation. This includes overwriting device
+ identifying fields such as the MAC address, VPD area, and device
+ serial number. It is expected that this combination be used with an
+ image customized for the specific device.
+
+The ice hardware does not support overwriting only identifiers while
+preserving settings, and thus ``DEVLINK_FLASH_OVERWRITE_IDENTIFIERS`` on its
+own will be rejected. If no overwrite mask is provided, the firmware will be
+instructed to preserve all settings and identifying fields when updating.
+
+Reload
+======
+
+The ``ice`` driver supports activating new firmware after a flash update
+using ``DEVLINK_CMD_RELOAD`` with the ``DEVLINK_RELOAD_ACTION_FW_ACTIVATE``
+action.
+
+.. code:: shell
+
+ $ devlink dev reload pci/0000:01:00.0 reload action fw_activate
+
+The new firmware is activated by issuing a device specific Embedded
+Management Processor reset which requests the device to reset and reload the
+EMP firmware image.
+
+The driver does not currently support reloading the driver via
+``DEVLINK_RELOAD_ACTION_DRIVER_REINIT``.
+
+Port split
+==========
+
+The ``ice`` driver supports port splitting only for port 0, as the FW has
+a predefined set of available port split options for the whole device.
+
+A system reboot is required for port split to be applied.
+
+The following command will select the port split option with 4 ports:
+
+.. code:: shell
+
+ $ devlink port split pci/0000:16:00.0/0 count 4
+
+The list of all available port options will be printed to dynamic debug after
+each ``split`` and ``unsplit`` command. The first option is the default.
+
+.. code:: shell
+
+ ice 0000:16:00.0: Available port split options and max port speeds (Gbps):
+ ice 0000:16:00.0: Status Split Quad 0 Quad 1
+ ice 0000:16:00.0: count L0 L1 L2 L3 L4 L5 L6 L7
+ ice 0000:16:00.0: Active 2 100 - - - 100 - - -
+ ice 0000:16:00.0: 2 50 - 50 - - - - -
+ ice 0000:16:00.0: Pending 4 25 25 25 25 - - - -
+ ice 0000:16:00.0: 4 25 25 - - 25 25 - -
+ ice 0000:16:00.0: 8 10 10 10 10 10 10 10 10
+ ice 0000:16:00.0: 1 100 - - - - - - -
+
+There could be multiple FW port options with the same port split count. When
+the same port split count request is issued again, the next FW port option with
+the same port split count will be selected.
+
+``devlink port unsplit`` will select the option with a split count of 1. If
+there is no FW option available with split count 1, you will receive an error.
+
+Regions
+=======
+
+The ``ice`` driver implements the following regions for accessing internal
+device data.
+
+.. list-table:: regions implemented
+ :widths: 15 85
+
+ * - Name
+ - Description
+ * - ``nvm-flash``
+ - The contents of the entire flash chip, sometimes referred to as
+ the device's Non Volatile Memory.
+ * - ``shadow-ram``
+ - The contents of the Shadow RAM, which is loaded from the beginning
+ of the flash. Although the contents are primarily from the flash,
+ this area also contains data generated during device boot which is
+ not stored in flash.
+ * - ``device-caps``
+ - The contents of the device firmware's capabilities buffer. Useful to
+ determine the current state and configuration of the device.
+
+Both the ``nvm-flash`` and ``shadow-ram`` regions can be accessed without a
+snapshot. The ``device-caps`` region requires a snapshot as the contents are
+sent by firmware and can't be split into separate reads.
+
+Users can request an immediate capture of a snapshot for all three regions
+via the ``DEVLINK_CMD_REGION_NEW`` command.
+
+.. code:: shell
+
+ $ devlink region show
+ pci/0000:01:00.0/nvm-flash: size 10485760 snapshot [] max 1
+ pci/0000:01:00.0/device-caps: size 4096 snapshot [] max 10
+
+ $ devlink region new pci/0000:01:00.0/nvm-flash snapshot 1
+ $ devlink region dump pci/0000:01:00.0/nvm-flash snapshot 1
+
+ $ devlink region dump pci/0000:01:00.0/nvm-flash snapshot 1
+ 0000000000000000 0014 95dc 0014 9514 0035 1670 0034 db30
+ 0000000000000010 0000 0000 ffff ff04 0029 8c00 0028 8cc8
+ 0000000000000020 0016 0bb8 0016 1720 0000 0000 c00f 3ffc
+ 0000000000000030 bada cce5 bada cce5 bada cce5 bada cce5
+
+ $ devlink region read pci/0000:01:00.0/nvm-flash snapshot 1 address 0 length 16
+ 0000000000000000 0014 95dc 0014 9514 0035 1670 0034 db30
+
+ $ devlink region delete pci/0000:01:00.0/nvm-flash snapshot 1
+
+ $ devlink region new pci/0000:01:00.0/device-caps snapshot 1
+ $ devlink region dump pci/0000:01:00.0/device-caps snapshot 1
+ 0000000000000000 01 00 01 00 00 00 00 00 01 00 00 00 00 00 00 00
+ 0000000000000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000020 02 00 02 01 32 03 00 00 0a 00 00 00 25 00 00 00
+ 0000000000000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000040 04 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000050 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000060 05 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000080 06 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000090 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000000a0 08 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000000b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000000c0 12 00 01 00 01 00 00 00 01 00 01 00 00 00 00 00
+ 00000000000000d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000000e0 13 00 01 00 00 01 00 00 00 00 00 00 00 00 00 00
+ 00000000000000f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000100 14 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000110 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000120 15 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000130 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000140 16 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000160 17 00 01 00 06 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000170 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000180 18 00 01 00 01 00 00 00 01 00 00 00 08 00 00 00
+ 0000000000000190 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000001a0 22 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000001c0 40 00 01 00 00 08 00 00 08 00 00 00 00 00 00 00
+ 00000000000001d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 00000000000001e0 41 00 01 00 00 08 00 00 00 00 00 00 00 00 00 00
+ 00000000000001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+ 0000000000000200 42 00 01 00 00 08 00 00 00 00 00 00 00 00 00 00
+ 0000000000000210 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+ $ devlink region delete pci/0000:01:00.0/device-caps snapshot 1
+
+Devlink Rate
+============
+
+The ``ice`` driver implements devlink-rate API. It allows for offload of
+the Hierarchical QoS to the hardware. It enables user to group Virtual
+Functions in a tree structure and assign supported parameters: tx_share,
+tx_max, tx_priority and tx_weight to each node in a tree. So effectively
+user gains an ability to control how much bandwidth is allocated for each
+VF group. This is later enforced by the HW.
+
+It is assumed that this feature is mutually exclusive with DCB performed
+in FW and ADQ, or any driver feature that would trigger changes in QoS,
+for example creation of the new traffic class. The driver will prevent DCB
+or ADQ configuration if user started making any changes to the nodes using
+devlink-rate API. To configure those features a driver reload is necessary.
+Correspondingly if ADQ or DCB will get configured the driver won't export
+hierarchy at all, or will remove the untouched hierarchy if those
+features are enabled after the hierarchy is exported, but before any
+changes are made.
+
+This feature is also dependent on switchdev being enabled in the system.
+It's required because devlink-rate requires devlink-port objects to be
+present, and those objects are only created in switchdev mode.
+
+If the driver is set to the switchdev mode, it will export internal
+hierarchy the moment VF's are created. Root of the tree is always
+represented by the node_0. This node can't be deleted by the user. Leaf
+nodes and nodes with children also can't be deleted.
+
+.. list-table:: Attributes supported
+ :widths: 15 85
+
+ * - Name
+ - Description
+ * - ``tx_max``
+ - maximum bandwidth to be consumed by the tree Node. Rate Limit is
+ an absolute number specifying a maximum amount of bytes a Node may
+ consume during the course of one second. Rate limit guarantees
+ that a link will not oversaturate the receiver on the remote end
+ and also enforces an SLA between the subscriber and network
+ provider.
+ * - ``tx_share``
+ - minimum bandwidth allocated to a tree node when it is not blocked.
+ It specifies an absolute BW. While tx_max defines the maximum
+ bandwidth the node may consume, the tx_share marks committed BW
+ for the Node.
+ * - ``tx_priority``
+ - allows for usage of strict priority arbiter among siblings. This
+ arbitration scheme attempts to schedule nodes based on their
+ priority as long as the nodes remain within their bandwidth limit.
+ Range 0-7. Nodes with priority 7 have the highest priority and are
+ selected first, while nodes with priority 0 have the lowest
+ priority. Nodes that have the same priority are treated equally.
+ * - ``tx_weight``
+ - allows for usage of Weighted Fair Queuing arbitration scheme among
+ siblings. This arbitration scheme can be used simultaneously with
+ the strict priority. Range 1-200. Only relative values matter for
+ arbitration.
+
+``tx_priority`` and ``tx_weight`` can be used simultaneously. In that case
+nodes with the same priority form a WFQ subgroup in the sibling group
+and arbitration among them is based on assigned weights.
+
+.. code:: shell
+
+ # enable switchdev
+ $ devlink dev eswitch set pci/0000:4b:00.0 mode switchdev
+
+ # at this point driver should export internal hierarchy
+ $ echo 2 > /sys/class/net/ens785np0/device/sriov_numvfs
+
+ $ devlink port function rate show
+ pci/0000:4b:00.0/node_25: type node parent node_24
+ pci/0000:4b:00.0/node_24: type node parent node_0
+ pci/0000:4b:00.0/node_32: type node parent node_31
+ pci/0000:4b:00.0/node_31: type node parent node_30
+ pci/0000:4b:00.0/node_30: type node parent node_16
+ pci/0000:4b:00.0/node_19: type node parent node_18
+ pci/0000:4b:00.0/node_18: type node parent node_17
+ pci/0000:4b:00.0/node_17: type node parent node_16
+ pci/0000:4b:00.0/node_14: type node parent node_5
+ pci/0000:4b:00.0/node_5: type node parent node_3
+ pci/0000:4b:00.0/node_13: type node parent node_4
+ pci/0000:4b:00.0/node_12: type node parent node_4
+ pci/0000:4b:00.0/node_11: type node parent node_4
+ pci/0000:4b:00.0/node_10: type node parent node_4
+ pci/0000:4b:00.0/node_9: type node parent node_4
+ pci/0000:4b:00.0/node_8: type node parent node_4
+ pci/0000:4b:00.0/node_7: type node parent node_4
+ pci/0000:4b:00.0/node_6: type node parent node_4
+ pci/0000:4b:00.0/node_4: type node parent node_3
+ pci/0000:4b:00.0/node_3: type node parent node_16
+ pci/0000:4b:00.0/node_16: type node parent node_15
+ pci/0000:4b:00.0/node_15: type node parent node_0
+ pci/0000:4b:00.0/node_2: type node parent node_1
+ pci/0000:4b:00.0/node_1: type node parent node_0
+ pci/0000:4b:00.0/node_0: type node
+ pci/0000:4b:00.0/1: type leaf parent node_25
+ pci/0000:4b:00.0/2: type leaf parent node_25
+
+ # let's create some custom node
+ $ devlink port function rate add pci/0000:4b:00.0/node_custom parent node_0
+
+ # second custom node
+ $ devlink port function rate add pci/0000:4b:00.0/node_custom_1 parent node_custom
+
+ # reassign second VF to newly created branch
+ $ devlink port function rate set pci/0000:4b:00.0/2 parent node_custom_1
+
+ # assign tx_weight to the VF
+ $ devlink port function rate set pci/0000:4b:00.0/2 tx_weight 5
+
+ # assign tx_share to the VF
+ $ devlink port function rate set pci/0000:4b:00.0/2 tx_share 500Mbps