@@ -1,8 +1,10 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
Linux* Driver for Intel(R) Ethernet Network Connection
======================================================
Intel Gigabit Linux driver.
-Copyright(c) 1999 - 2013 Intel Corporation.
+Copyright(c) 2008-2018 Intel Corporation.
Contents
========
@@ -12,48 +14,43 @@ Contents
- Additional Configurations
- Support
+
Identifying Your Adapter
========================
+For information on how to identify your adapter, and for the latest Intel
+network drivers, refer to the Intel Support website:
+https://www.intel.com/support
-The e1000e driver supports all PCI Express Intel(R) Gigabit Network
-Connections, except those that are 82575, 82576 and 82580-based*.
-
-* NOTE: The Intel(R) PRO/1000 P Dual Port Server Adapter is supported by
- the e1000 driver, not the e1000e driver due to the 82546 part being used
- behind a PCI Express bridge.
-For more information on how to identify your adapter, go to the Adapter &
-Driver ID Guide at:
-
- http://support.intel.com/support/go/network/adapter/idguide.htm
+Command Line Parameters
+=======================
+If the driver is built as a module, the following optional parameters are used
+by entering them on the command line with the modprobe command using this
+syntax::
-For the latest Intel network drivers for Linux, refer to the following
-website. In the search field, enter your adapter name or type, or use the
-networking link on the left to search for your adapter:
+ modprobe e1000e [<option>=<VAL1>,<VAL2>,...]
- http://support.intel.com/support/go/network/adapter/home.htm
+There needs to be a <VAL#> for each network port in the system supported by
+this driver. The values will be applied to each instance, in function order.
+For example::
-Command Line Parameters
-=======================
+ modprobe e1000e InterruptThrottleRate=16000,16000
+In this case, there are two network ports supported by e1000e in the system.
The default value for each parameter is generally the recommended setting,
unless otherwise noted.
-NOTES: For more information about the InterruptThrottleRate,
- RxIntDelay, TxIntDelay, RxAbsIntDelay, and TxAbsIntDelay
- parameters, see the application note at:
- http://www.intel.com/design/network/applnots/ap450.htm
+NOTE: A descriptor describes a data buffer and attributes related to the data
+buffer. This information is accessed by the hardware.
InterruptThrottleRate
---------------------
-Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative,
- 4=simplified balancing)
-Default Value: 3
+:Valid Range: 0,1,3,4,100-100000
+:Default Value: 3
-The driver can limit the amount of interrupts per second that the adapter
-will generate for incoming packets. It does this by writing a value to the
-adapter that is based on the maximum amount of interrupts that the adapter
-will generate per second.
+Interrupt Throttle Rate controls the number of interrupts each interrupt
+vector can generate per second. Increasing ITR lowers latency at the cost of
+increased CPU utilization, though it may help throughput in some circumstances.
Setting InterruptThrottleRate to a value greater or equal to 100
will program the adapter to send out a maximum of that many interrupts
@@ -81,232 +78,305 @@ for small amounts of traffic and/or a significant percentage of small
packets; and "Lowest latency", for almost completely small packets or
minimal traffic.
-In dynamic conservative mode, the InterruptThrottleRate value is set to 4000
-for traffic that falls in class "Bulk traffic". If traffic falls in the "Low
-latency" or "Lowest latency" class, the InterruptThrottleRate is increased
-stepwise to 20000. This default mode is suitable for most applications.
-
-For situations where low latency is vital such as cluster or
-grid computing, the algorithm can reduce latency even more when
-InterruptThrottleRate is set to mode 1. In this mode, which operates
-the same as mode 3, the InterruptThrottleRate will be increased stepwise to
-70000 for traffic in class "Lowest latency".
-
-In simplified mode the interrupt rate is based on the ratio of TX and
-RX traffic. If the bytes per second rate is approximately equal, the
-interrupt rate will drop as low as 2000 interrupts per second. If the
-traffic is mostly transmit or mostly receive, the interrupt rate could
-be as high as 8000.
-
-Setting InterruptThrottleRate to 0 turns off any interrupt moderation
-and may improve small packet latency, but is generally not suitable
-for bulk throughput traffic.
-
-NOTE: InterruptThrottleRate takes precedence over the TxAbsIntDelay and
- RxAbsIntDelay parameters. In other words, minimizing the receive
- and/or transmit absolute delays does not force the controller to
- generate more interrupts than what the Interrupt Throttle Rate
- allows.
-
-NOTE: When e1000e is loaded with default settings and multiple adapters
- are in use simultaneously, the CPU utilization may increase non-
- linearly. In order to limit the CPU utilization without impacting
- the overall throughput, we recommend that you load the driver as
- follows:
-
- modprobe e1000e InterruptThrottleRate=3000,3000,3000
-
- This sets the InterruptThrottleRate to 3000 interrupts/sec for
- the first, second, and third instances of the driver. The range
- of 2000 to 3000 interrupts per second works on a majority of
- systems and is a good starting point, but the optimal value will
- be platform-specific. If CPU utilization is not a concern, use
- RX_POLLING (NAPI) and default driver settings.
+ - 0: Off
+ Turns off any interrupt moderation and may improve small packet latency.
+ However, this is generally not suitable for bulk throughput traffic due
+ to the increased CPU utilization of the higher interrupt rate.
+ - 1: Dynamic mode
+ This mode attempts to moderate interrupts per vector while maintaining
+ very low latency. This can sometimes cause extra CPU utilization. If
+ planning on deploying e1000e in a latency sensitive environment, this
+ parameter should be considered.
+ - 3: Dynamic Conservative mode (default)
+ In dynamic conservative mode, the InterruptThrottleRate value is set to
+ 4000 for traffic that falls in class "Bulk traffic". If traffic falls in
+ the "Low latency" or "Lowest latency" class, the InterruptThrottleRate is
+ increased stepwise to 20000. This default mode is suitable for most
+ applications.
+ - 4: Simplified Balancing mode
+ In simplified mode the interrupt rate is based on the ratio of TX and
+ RX traffic. If the bytes per second rate is approximately equal, the
+ interrupt rate will drop as low as 2000 interrupts per second. If the
+ traffic is mostly transmit or mostly receive, the interrupt rate could
+ be as high as 8000.
+ - 100-100000:
+ Setting InterruptThrottleRate to a value greater or equal to 100
+ will program the adapter to send at most that many interrupts per second,
+ even if more packets have come in. This reduces interrupt load on the
+ system and can lower CPU utilization under heavy load, but will increase
+ latency as packets are not processed as quickly.
+
+NOTE: InterruptThrottleRate takes precedence over the TxAbsIntDelay and
+RxAbsIntDelay parameters. In other words, minimizing the receive and/or
+transmit absolute delays does not force the controller to generate more
+interrupts than what the Interrupt Throttle Rate allows.
RxIntDelay
----------
-Valid Range: 0-65535 (0=off)
-Default Value: 0
+:Valid Range: 0-65535 (0=off)
+:Default Value: 0
This value delays the generation of receive interrupts in units of 1.024
-microseconds. Receive interrupt reduction can improve CPU efficiency if
-properly tuned for specific network traffic. Increasing this value adds
-extra latency to frame reception and can end up decreasing the throughput
-of TCP traffic. If the system is reporting dropped receives, this value
-may be set too high, causing the driver to run out of available receive
-descriptors.
-
-CAUTION: When setting RxIntDelay to a value other than 0, adapters may
- hang (stop transmitting) under certain network conditions. If
- this occurs a NETDEV WATCHDOG message is logged in the system
- event log. In addition, the controller is automatically reset,
- restoring the network connection. To eliminate the potential
- for the hang ensure that RxIntDelay is set to 0.
+microseconds. Receive interrupt reduction can improve CPU efficiency if
+properly tuned for specific network traffic. Increasing this value adds extra
+latency to frame reception and can end up decreasing the throughput of TCP
+traffic. If the system is reporting dropped receives, this value may be set
+too high, causing the driver to run out of available receive descriptors.
+
+CAUTION: When setting RxIntDelay to a value other than 0, adapters may hang
+(stop transmitting) under certain network conditions. If this occurs a NETDEV
+WATCHDOG message is logged in the system event log. In addition, the
+controller is automatically reset, restoring the network connection. To
+eliminate the potential for the hang ensure that RxIntDelay is set to 0.
RxAbsIntDelay
-------------
-Valid Range: 0-65535 (0=off)
-Default Value: 8
+:Valid Range: 0-65535 (0=off)
+:Default Value: 8
This value, in units of 1.024 microseconds, limits the delay in which a
-receive interrupt is generated. Useful only if RxIntDelay is non-zero,
-this value ensures that an interrupt is generated after the initial
-packet is received within the set amount of time. Proper tuning,
-along with RxIntDelay, may improve traffic throughput in specific network
-conditions.
+receive interrupt is generated. This value ensures that an interrupt is
+generated after the initial packet is received within the set amount of time,
+which is useful only if RxIntDelay is non-zero. Proper tuning, along with
+RxIntDelay, may improve traffic throughput in specific network conditions.
TxIntDelay
----------
-Valid Range: 0-65535 (0=off)
-Default Value: 8
+:Valid Range: 0-65535 (0=off)
+:Default Value: 8
-This value delays the generation of transmit interrupts in units of
-1.024 microseconds. Transmit interrupt reduction can improve CPU
-efficiency if properly tuned for specific network traffic. If the
-system is reporting dropped transmits, this value may be set too high
-causing the driver to run out of available transmit descriptors.
+This value delays the generation of transmit interrupts in units of 1.024
+microseconds. Transmit interrupt reduction can improve CPU efficiency if
+properly tuned for specific network traffic. If the system is reporting
+dropped transmits, this value may be set too high causing the driver to run
+out of available transmit descriptors.
TxAbsIntDelay
-------------
-Valid Range: 0-65535 (0=off)
-Default Value: 32
+:Valid Range: 0-65535 (0=off)
+:Default Value: 32
This value, in units of 1.024 microseconds, limits the delay in which a
-transmit interrupt is generated. Useful only if TxIntDelay is non-zero,
-this value ensures that an interrupt is generated after the initial
-packet is sent on the wire within the set amount of time. Proper tuning,
-along with TxIntDelay, may improve traffic throughput in specific
-network conditions.
+transmit interrupt is generated. It is useful only if TxIntDelay is non-zero.
+It ensures that an interrupt is generated after the initial Packet is sent on
+the wire within the set amount of time. Proper tuning, along with TxIntDelay,
+may improve traffic throughput in specific network conditions.
-Copybreak
+copybreak
---------
-Valid Range: 0-xxxxxxx (0=off)
-Default Value: 256
+:Valid Range: 0-xxxxxxx (0=off)
+:Default Value: 256
-Driver copies all packets below or equaling this size to a fresh RX
+The driver copies all packets below or equaling this size to a fresh receive
buffer before handing it up the stack.
+This parameter differs from other parameters because it is a single (not 1,1,1
+etc.) parameter applied to all driver instances and it is also available
+during runtime at /sys/module/e1000e/parameters/copybreak.
+
+To use copybreak, type::
-This parameter is different than other parameters, in that it is a
-single (not 1,1,1 etc.) parameter applied to all driver instances and
-it is also available during runtime at
-/sys/module/e1000e/parameters/copybreak
+ modprobe e1000e.ko copybreak=128
SmartPowerDownEnable
--------------------
-Valid Range: 0-1
-Default Value: 0 (disabled)
+:Valid Range: 0,1
+:Default Value: 0 (disabled)
-Allows PHY to turn off in lower power states. The user can set this parameter
-in supported chipsets.
+Allows the PHY to turn off in lower power states. The user can turn off this
+parameter in supported chipsets.
KumeranLockLoss
---------------
-Valid Range: 0-1
-Default Value: 1 (enabled)
+:Valid Range: 0,1
+:Default Value: 1 (enabled)
-This workaround skips resetting the PHY at shutdown for the initial
-silicon releases of ICH8 systems.
+This workaround skips resetting the PHY at shutdown for the initial silicon
+releases of ICH8 systems.
IntMode
-------
-Valid Range: 0-2 (0=legacy, 1=MSI, 2=MSI-X)
-Default Value: 2
+:Valid Range: 0-2
+:Default Value: 0
-Allows changing the interrupt mode at module load time, without requiring a
-recompile. If the driver load fails to enable a specific interrupt mode, the
-driver will try other interrupt modes, from least to most compatible. The
-interrupt order is MSI-X, MSI, Legacy. If specifying MSI (IntMode=1)
-interrupts, only MSI and Legacy will be attempted.
+ +-------+----------------+
+ | Value | Interrupt Mode |
+ +=======+================+
+ | 0 | Legacy |
+ +-------+----------------+
+ | 1 | MSI |
+ +-------+----------------+
+ | 2 | MSI-X |
+ +-------+----------------+
+
+IntMode allows load time control over the type of interrupt registered for by
+the driver. MSI-X is required for multiple queue support, and some kernels and
+combinations of kernel .config options will force a lower level of interrupt
+support.
+
+This command will show different values for each type of interrupt::
+
+ cat /proc/interrupts
CrcStripping
------------
-Valid Range: 0-1
-Default Value: 1 (enabled)
+:Valid Range: 0,1
+:Default Value: 1 (enabled)
-Strip the CRC from received packets before sending up the network stack. If
+Strip the CRC from received packets before sending up the network stack. If
you have a machine with a BMC enabled but cannot receive IPMI traffic after
loading or enabling the driver, try disabling this feature.
WriteProtectNVM
---------------
-Valid Range: 0,1
-Default Value: 1
+:Valid Range: 0,1
+:Default Value: 1 (enabled)
If set to 1, configure the hardware to ignore all write/erase cycles to the
GbE region in the ICHx NVM (in order to prevent accidental corruption of the
NVM). This feature can be disabled by setting the parameter to 0 during initial
driver load.
+
NOTE: The machine must be power cycled (full off/on) when enabling NVM writes
via setting the parameter to zero. Once the NVM has been locked (via the
parameter at 1 when the driver loads) it cannot be unlocked except via power
cycle.
-Additional Configurations
-=========================
+Debug
+-----
+:Valid Range: 0-16 (0=none,...,16=all)
+:Default Value: 0
- Jumbo Frames
- ------------
- Jumbo Frames support is enabled by changing the MTU to a value larger than
- the default of 1500. Use the ifconfig command to increase the MTU size.
- For example:
+This parameter adjusts the level of debug messages displayed in the system logs.
+
+
+Additional Features and Configurations
+======================================
+
+Jumbo Frames
+------------
+Jumbo Frames support is enabled by changing the Maximum Transmission Unit (MTU)
+to a value larger than the default value of 1500.
- ifconfig eth<x> mtu 9000 up
+Use the ifconfig command to increase the MTU size. For example, enter the
+following where <x> is the interface number::
- This setting is not saved across reboots.
+ ifconfig eth<x> mtu 9000 up
- Notes:
+Alternatively, you can use the ip command as follows::
- - The maximum MTU setting for Jumbo Frames is 9216. This value coincides
- with the maximum Jumbo Frames size of 9234 bytes.
+ ip link set mtu 9000 dev eth<x>
+ ip link set up dev eth<x>
- - Using Jumbo frames at 10 or 100 Mbps is not supported and may result in
- poor performance or loss of link.
+This setting is not saved across reboots. The setting change can be made
+permanent by adding 'MTU=9000' to the file:
- - Some adapters limit Jumbo Frames sized packets to a maximum of
- 4096 bytes and some adapters do not support Jumbo Frames.
+- For RHEL: /etc/sysconfig/network-scripts/ifcfg-eth<x>
+- For SLES: /etc/sysconfig/network/<config_file>
- - Jumbo Frames cannot be configured on an 82579-based Network device, if
- MACSec is enabled on the system.
+NOTE: The maximum MTU setting for Jumbo Frames is 8996. This value coincides
+with the maximum Jumbo Frames size of 9018 bytes.
- ethtool
- -------
- The driver utilizes the ethtool interface for driver configuration and
- diagnostics, as well as displaying statistical information. We
- strongly recommend downloading the latest version of ethtool at:
+NOTE: Using Jumbo frames at 10 or 100 Mbps is not supported and may result in
+poor performance or loss of link.
- https://kernel.org/pub/software/network/ethtool/
+NOTE: The following adapters limit Jumbo Frames sized packets to a maximum of
+4088 bytes:
- NOTE: When validating enable/disable tests on some parts (82578, for example)
- you need to add a few seconds between tests when working with ethtool.
+ - Intel(R) 82578DM Gigabit Network Connection
+ - Intel(R) 82577LM Gigabit Network Connection
- Speed and Duplex
- ----------------
- Speed and Duplex are configured through the ethtool* utility. For
- instructions, refer to the ethtool man page.
+The following adapters do not support Jumbo Frames:
- Enabling Wake on LAN* (WoL)
- ---------------------------
- WoL is configured through the ethtool* utility. For instructions on
- enabling WoL with ethtool, refer to the ethtool man page.
+ - Intel(R) PRO/1000 Gigabit Server Adapter
+ - Intel(R) PRO/1000 PM Network Connection
+ - Intel(R) 82562G 10/100 Network Connection
+ - Intel(R) 82562G-2 10/100 Network Connection
+ - Intel(R) 82562GT 10/100 Network Connection
+ - Intel(R) 82562GT-2 10/100 Network Connection
+ - Intel(R) 82562V 10/100 Network Connection
+ - Intel(R) 82562V-2 10/100 Network Connection
+ - Intel(R) 82566DC Gigabit Network Connection
+ - Intel(R) 82566DC-2 Gigabit Network Connection
+ - Intel(R) 82566DM Gigabit Network Connection
+ - Intel(R) 82566MC Gigabit Network Connection
+ - Intel(R) 82566MM Gigabit Network Connection
+ - Intel(R) 82567V-3 Gigabit Network Connection
+ - Intel(R) 82577LC Gigabit Network Connection
+ - Intel(R) 82578DC Gigabit Network Connection
- WoL will be enabled on the system during the next shut down or reboot.
- For this driver version, in order to enable WoL, the e1000e driver must be
- loaded when shutting down or rebooting the system.
+NOTE: Jumbo Frames cannot be configured on an 82579-based Network device if
+MACSec is enabled on the system.
+
+
+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/
+
+NOTE: When validating enable/disable tests on some parts (for example, 82578),
+it is necessary to add a few seconds between tests when working with ethtool.
+
+
+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.
+
+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.
+
+
+Enabling Wake on LAN* (WoL)
+---------------------------
+WoL is configured through the ethtool* utility.
+
+WoL will be enabled on the system during the next shut down or reboot. For
+this driver version, in order to enable WoL, the e1000e driver must be loaded
+prior to shutting down or suspending the system.
+
+NOTE: Wake on LAN is only supported on port A for the following devices:
+- Intel(R) PRO/1000 PT Dual Port Network Connection
+- Intel(R) PRO/1000 PT Dual Port Server Connection
+- Intel(R) PRO/1000 PT Dual Port Server Adapter
+- Intel(R) PRO/1000 PF Dual Port Server Adapter
+- Intel(R) PRO/1000 PT Quad Port Server Adapter
+- Intel(R) Gigabit PT Quad Port Server ExpressModule
- In most cases Wake On LAN is only supported on port A for multiple port
- adapters. To verify if a port supports Wake on Lan run ethtool eth<X>.
Support
=======
-
For general information, go to the Intel support website at:
- www.intel.com/support/
+https://www.intel.com/support/
or the Intel Wired Networking project hosted by Sourceforge at:
- http://sourceforge.net/projects/e1000
+https://sourceforge.net/projects/e1000
-If an issue is identified with the released source code on the supported
-kernel with a supported adapter, email the specific information related
-to the issue to e1000-devel@lists.sf.net
+If an issue is identified with the released source code on a supported kernel
+with a supported adapter, email the specific information related to the issue
+to e1000-devel@lists.sf.net.