.. SPDX-License-Identifier: GPL-2.0+ ================================================================= Linux Base Driver for the Intel(R) Ethernet Controller 700 Series ================================================================= Intel 40 Gigabit Linux driver. Copyright(c) 1999-2018 Intel Corporation. Contents ======== - Overview - Identifying Your Adapter - Intel(R) Ethernet Flow Director - Additional Configurations - Known Issues - Support Driver information can be obtained using ethtool, lspci, and ifconfig. Instructions on updating ethtool can be found in the section Additional Configurations later in this document. For questions related to hardware requirements, refer to the documentation supplied with your Intel adapter. All hardware requirements listed apply to use with Linux. Identifying Your Adapter ======================== The driver is compatible with devices based on the following: * Intel(R) Ethernet Controller X710 * Intel(R) Ethernet Controller XL710 * Intel(R) Ethernet Network Connection X722 * Intel(R) Ethernet Controller XXV710 For the best performance, make sure the latest NVM/FW is installed on your device. For information on how to identify your adapter, and for the latest NVM/FW images and Intel network drivers, refer to the Intel Support website: https://www.intel.com/support SFP+ and QSFP+ Devices ---------------------- For information about supported media, refer to this document: https://www.intel.com/content/dam/www/public/us/en/documents/release-notes/xl710-ethernet-controller-feature-matrix.pdf NOTE: Some adapters based on the Intel(R) Ethernet Controller 700 Series only support Intel Ethernet Optics modules. On these adapters, other modules are not supported and will not function. In all cases Intel recommends using Intel Ethernet Optics; other modules may function but are not validated by Intel. Contact Intel for supported media types. NOTE: For connections based on Intel(R) Ethernet Controller 700 Series, support is dependent on your system board. Please see your vendor for details. NOTE: In systems that do not have adequate airflow to cool the adapter and optical modules, you must use high temperature optical modules. Virtual Functions (VFs) ----------------------- Use sysfs to enable VFs. For example:: #echo $num_vf_enabled > /sys/class/net/$dev/device/sriov_numvfs #enable VFs #echo 0 > /sys/class/net/$dev/device/sriov_numvfs #disable VFs For example, the following instructions will configure PF eth0 and the first VF on VLAN 10:: $ ip link set dev eth0 vf 0 vlan 10 VLAN Tag Packet Steering ------------------------ Allows you to send all packets with a specific VLAN tag to a particular SR-IOV virtual function (VF). Further, this feature allows you to designate a particular VF as trusted, and allows that trusted VF to request selective promiscuous mode on the Physical Function (PF). To set a VF as trusted or untrusted, enter the following command in the Hypervisor:: # ip link set dev eth0 vf 1 trust [on|off] Once the VF is designated as trusted, use the following commands in the VM to set the VF to promiscuous mode. :: For promiscuous all: #ip link set eth2 promisc on Where eth2 is a VF interface in the VM For promiscuous Multicast: #ip link set eth2 allmulticast on Where eth2 is a VF interface in the VM NOTE: By default, the ethtool priv-flag vf-true-promisc-support is set to "off",meaning that promiscuous mode for the VF will be limited. To set the promiscuous mode for the VF to true promiscuous and allow the VF to see all ingress traffic, use the following command:: #ethtool -set-priv-flags p261p1 vf-true-promisc-support on The vf-true-promisc-support priv-flag does not enable promiscuous mode; rather, it designates which type of promiscuous mode (limited or true) you will get when you enable promiscuous mode using the ip link commands above. Note that this is a global setting that affects the entire device. However,the vf-true-promisc-support priv-flag is only exposed to the first PF of the device. The PF remains in limited promiscuous mode (unless it is in MFP mode) regardless of the vf-true-promisc-support setting. Now add a VLAN interface on the VF interface:: #ip link add link eth2 name eth2.100 type vlan id 100 Note that the order in which you set the VF to promiscuous mode and add the VLAN interface does not matter (you can do either first). The end result in this example is that the VF will get all traffic that is tagged with VLAN 100. Intel(R) Ethernet Flow Director ------------------------------- The Intel Ethernet Flow Director performs the following tasks: - Directs receive packets according to their flows to different queues. - Enables tight control on routing a flow in the platform. - Matches flows and CPU cores for flow affinity. - Supports multiple parameters for flexible flow classification and load balancing (in SFP mode only). NOTE: The Linux i40e driver supports the following flow types: IPv4, TCPv4, and UDPv4. For a given flow type, it supports valid combinations of IP addresses (source or destination) and UDP/TCP ports (source and destination). For example, you can supply only a source IP address, a source IP address and a destination port, or any combination of one or more of these four parameters. NOTE: The Linux i40e driver allows you to filter traffic based on a user-defined flexible two-byte pattern and offset by using the ethtool user-def and mask fields. Only L3 and L4 flow types are supported for user-defined flexible filters. For a given flow type, you must clear all Intel Ethernet Flow Director filters before changing the input set (for that flow type). To enable or disable the Intel Ethernet Flow Director:: # ethtool -K ethX ntuple When disabling ntuple filters, all the user programmed filters are flushed from the driver cache and hardware. All needed filters must be re-added when ntuple is re-enabled. To add a filter that directs packet to queue 2, use -U or -N switch:: # ethtool -N ethX flow-type tcp4 src-ip 192.168.10.1 dst-ip \ 192.168.10.2 src-port 2000 dst-port 2001 action 2 [loc 1] To set a filter using only the source and destination IP address:: # ethtool -N ethX flow-type tcp4 src-ip 192.168.10.1 dst-ip \ 192.168.10.2 action 2 [loc 1] To see the list of filters currently present:: # ethtool <-u|-n> ethX Application Targeted Routing (ATR) Perfect Filters -------------------------------------------------- ATR is enabled by default when the kernel is in multiple transmit queue mode. An ATR Intel Ethernet Flow Director filter rule is added when a TCP-IP flow starts and is deleted when the flow ends. When a TCP-IP Intel Ethernet Flow Director rule is added from ethtool (Sideband filter), ATR is turned off by the driver. To re-enable ATR, the sideband can be disabled with the ethtool -K option. For example:: ethtool -K [adapter] ntuple [off|on] If sideband is re-enabled after ATR is re-enabled, ATR remains enabled until a TCP-IP flow is added. When all TCP-IP sideband rules are deleted, ATR is automatically re-enabled. Packets that match the ATR rules are counted in fdir_atr_match stats in ethtool, which also can be used to verify whether ATR rules still exist. Sideband Perfect Filters ------------------------ Sideband Perfect Filters are used to direct traffic that matches specified characteristics. They are enabled through ethtool's ntuple interface. To add a new filter use the following command:: ethtool -U flow-type src-ip dst-ip src-port \ dst-port action Where: - the ethernet device to program - can be ip4, tcp4, udp4, or sctp4 - the ip address to match on - the port number to match on - the queue to direct traffic towards (-1 discards matching traffic) Use the following command to display all of the active filters:: ethtool -u Use the following command to delete a filter:: ethtool -U delete Where is the filter id displayed when printing all the active filters, and may also have been specified using "loc " when adding the filter. The following example matches TCP traffic sent from 192.168.0.1, port 5300, directed to 192.168.0.5, port 80, and sends it to queue 7:: ethtool -U enp130s0 flow-type tcp4 src-ip 192.168.0.1 dst-ip 192.168.0.5 \ src-port 5300 dst-port 80 action 7 For each flow-type, the programmed filters must all have the same matching input set. For example, issuing the following two commands is acceptable:: ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7 ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.5 src-port 55 action 10 Issuing the next two commands, however, is not acceptable, since the first specifies src-ip and the second specifies dst-ip:: ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7 ethtool -U enp130s0 flow-type ip4 dst-ip 192.168.0.5 src-port 55 action 10 The second command will fail with an error. You may program multiple filters with the same fields, using different values, but, on one device, you may not program two tcp4 filters with different matching fields. Matching on a sub-portion of a field is not supported by the i40e driver, thus partial mask fields are not supported. The driver also supports matching user-defined data within the packet payload. This flexible data is specified using the "user-def" field of the ethtool command in the following way: +----------------------------+--------------------------+ | 31 28 24 20 16 | 15 12 8 4 0 | +----------------------------+--------------------------+ | offset into packet payload | 2 bytes of flexible data | +----------------------------+--------------------------+ For example, :: ... user-def 0x4FFFF ... tells the filter to look 4 bytes into the payload and match that value against 0xFFFF. The offset is based on the beginning of the payload, and not the beginning of the packet. Thus :: flow-type tcp4 ... user-def 0x8BEAF ... would match TCP/IPv4 packets which have the value 0xBEAF 8 bytes into the TCP/IPv4 payload. Note that ICMP headers are parsed as 4 bytes of header and 4 bytes of payload. Thus to match the first byte of the payload, you must actually add 4 bytes to the offset. Also note that ip4 filters match both ICMP frames as well as raw (unknown) ip4 frames, where the payload will be the L3 payload of the IP4 frame. The maximum offset is 64. The hardware will only read up to 64 bytes of data from the payload. The offset must be even because the flexible data is 2 bytes long and must be aligned to byte 0 of the packet payload. The user-defined flexible offset is also considered part of the input set and cannot be programmed separately for multiple filters of the same type. However, the flexible data is not part of the input set and multiple filters may use the same offset but match against different data. To create filters that direct traffic to a specific Virtual Function, use the "action" parameter. Specify the action as a 64 bit value, where the lower 32 bits represents the queue number, while the next 8 bits represent which VF. Note that 0 is the PF, so the VF identifier is offset by 1. For example:: ... action 0x800000002 ... specifies to direct traffic to Virtual Function 7 (8 minus 1) into queue 2 of that VF. Note that these filters will not break internal routing rules, and will not route traffic that otherwise would not have been sent to the specified Virtual Function. Setting the link-down-on-close Private Flag ------------------------------------------- When the link-down-on-close private flag is set to "on", the port's link will go down when the interface is brought down using the ifconfig ethX down command. Use ethtool to view and set link-down-on-close, as follows:: ethtool --show-priv-flags ethX ethtool --set-priv-flags ethX link-down-on-close [on|off] Viewing Link Messages --------------------- Link messages will not be displayed to the console if the distribution is restricting system messages. In order to see network driver link messages on your console, set dmesg to eight by entering the following:: dmesg -n 8 NOTE: This setting is not saved across reboots. Jumbo Frames ------------ Jumbo Frames support is enabled by changing the Maximum Transmission Unit (MTU) to a value larger than the default value of 1500. Use the ifconfig command to increase the MTU size. For example, enter the following where is the interface number:: ifconfig eth mtu 9000 up Alternatively, you can use the ip command as follows:: ip link set mtu 9000 dev eth ip link set up dev eth This setting is not saved across reboots. The setting change can be made permanent by adding 'MTU=9000' to the file:: /etc/sysconfig/network-scripts/ifcfg-eth // for RHEL /etc/sysconfig/network/ // for SLES NOTE: The maximum MTU setting for Jumbo Frames is 9702. This value coincides with the maximum Jumbo Frames size of 9728 bytes. NOTE: This driver will attempt to use multiple page sized buffers to receive each jumbo packet. This should help to avoid buffer starvation issues when allocating receive packets. ethtool ------- The driver utilizes the ethtool interface for driver configuration and diagnostics, as well as displaying statistical information. The latest ethtool version is required for this functionality. Download it at: https://www.kernel.org/pub/software/network/ethtool/ Supported ethtool Commands and Options for Filtering ---------------------------------------------------- -n --show-nfc Retrieves the receive network flow classification configurations. rx-flow-hash tcp4|udp4|ah4|esp4|sctp4|tcp6|udp6|ah6|esp6|sctp6 Retrieves the hash options for the specified network traffic type. -N --config-nfc Configures the receive network flow classification. rx-flow-hash tcp4|udp4|ah4|esp4|sctp4|tcp6|udp6|ah6|esp6|sctp6 m|v|t|s|d|f|n|r... Configures the hash options for the specified network traffic type. udp4 UDP over IPv4 udp6 UDP over IPv6 f Hash on bytes 0 and 1 of the Layer 4 header of the Rx packet. n Hash on bytes 2 and 3 of the Layer 4 header of the Rx packet. Speed and Duplex Configuration ------------------------------ In addressing speed and duplex configuration issues, you need to distinguish between copper-based adapters and fiber-based adapters. In the default mode, an Intel(R) Ethernet Network Adapter using copper connections will attempt to auto-negotiate with its link partner to determine the best setting. If the adapter cannot establish link with the link partner using auto-negotiation, you may need to manually configure the adapter and link partner to identical settings to establish link and pass packets. This should only be needed when attempting to link with an older switch that does not support auto-negotiation or one that has been forced to a specific speed or duplex mode. Your link partner must match the setting you choose. 1 Gbps speeds and higher cannot be forced. Use the autonegotiation advertising setting to manually set devices for 1 Gbps and higher. NOTE: You cannot set the speed for devices based on the Intel(R) Ethernet Network Adapter XXV710 based devices. Speed, duplex, and autonegotiation advertising are configured through the ethtool utility. Caution: Only experienced network administrators should force speed and duplex or change autonegotiation advertising manually. The settings at the switch must always match the adapter settings. Adapter performance may suffer or your adapter may not operate if you configure the adapter differently from your switch. An Intel(R) Ethernet Network Adapter using fiber-based connections, however, will not attempt to auto-negotiate with its link partner since those adapters operate only in full duplex and only at their native speed. NAPI ---- NAPI (Rx polling mode) is supported in the i40e driver. See :ref:`Documentation/networking/napi.rst ` for more information. Flow Control ------------ Ethernet Flow Control (IEEE 802.3x) can be configured with ethtool to enable receiving and transmitting pause frames for i40e. When transmit is enabled, pause frames are generated when the receive packet buffer crosses a predefined threshold. When receive is enabled, the transmit unit will halt for the time delay specified when a pause frame is received. NOTE: You must have a flow control capable link partner. Flow Control is on by default. Use ethtool to change the flow control settings. To enable or disable Rx or Tx Flow Control:: ethtool -A eth? rx tx Note: This command only enables or disables Flow Control if auto-negotiation is disabled. If auto-negotiation is enabled, this command changes the parameters used for auto-negotiation with the link partner. To enable or disable auto-negotiation:: ethtool -s eth? autoneg Note: Flow Control auto-negotiation is part of link auto-negotiation. Depending on your device, you may not be able to change the auto-negotiation setting. RSS Hash Flow ------------- Allows you to set the hash bytes per flow type and any combination of one or more options for Receive Side Scaling (RSS) hash byte configuration. :: # ethtool -N rx-flow-hash