--- /dev/null
+Linux* Base Driver for Intel(R) Ethernet Network Connection
+===========================================================
+
+Intel Gigabit Linux driver.
+Copyright(c) 1999 - 2013 Intel Corporation.
+
+Contents
+========
+
+- Identifying Your Adapter
+- Command Line Parameters
+- Speed and Duplex Configuration
+- Additional Configurations
+- Support
+
+Identifying Your Adapter
+========================
+
+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
+
+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:
+
+ http://support.intel.com/support/go/network/adapter/home.htm
+
+Command Line Parameters
+=======================
+
+The default value for each parameter is generally the recommended setting,
+unless otherwise noted.
+
+NOTES: For more information about the AutoNeg, Duplex, and Speed
+ parameters, see the "Speed and Duplex Configuration" section in
+ this document.
+
+ 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
+
+AutoNeg
+-------
+(Supported only on adapters with copper connections)
+Valid Range: 0x01-0x0F, 0x20-0x2F
+Default Value: 0x2F
+
+This parameter is a bit-mask that specifies the speed and duplex settings
+advertised by the adapter. When this parameter is used, the Speed and
+Duplex parameters must not be specified.
+
+NOTE: Refer to the Speed and Duplex section of this readme for more
+ information on the AutoNeg parameter.
+
+Duplex
+------
+(Supported only on adapters with copper connections)
+Valid Range: 0-2 (0=auto-negotiate, 1=half, 2=full)
+Default Value: 0
+
+This defines the direction in which data is allowed to flow. Can be
+either one or two-directional. If both Duplex and the link partner are
+set to auto-negotiate, the board auto-detects the correct duplex. If the
+link partner is forced (either full or half), Duplex defaults to half-
+duplex.
+
+FlowControl
+-----------
+Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx)
+Default Value: Reads flow control settings from the EEPROM
+
+This parameter controls the automatic generation(Tx) and response(Rx)
+to Ethernet PAUSE frames.
+
+InterruptThrottleRate
+---------------------
+(not supported on Intel(R) 82542, 82543 or 82544-based adapters)
+Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative,
+ 4=simplified balancing)
+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.
+
+Setting InterruptThrottleRate to a value greater or equal to 100
+will program the adapter to send out a maximum of 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.
+
+The default behaviour of the driver previously assumed a static
+InterruptThrottleRate value of 8000, providing a good fallback value for
+all traffic types,but lacking in small packet performance and latency.
+The hardware can handle many more small packets per second however, and
+for this reason an adaptive interrupt moderation algorithm was implemented.
+
+Since 7.3.x, the driver has two adaptive modes (setting 1 or 3) in which
+it dynamically adjusts the InterruptThrottleRate value based on the traffic
+that it receives. After determining the type of incoming traffic in the last
+timeframe, it will adjust the InterruptThrottleRate to an appropriate value
+for that traffic.
+
+The algorithm classifies the incoming traffic every interval into
+classes. Once the class is determined, the InterruptThrottleRate value is
+adjusted to suit that traffic type the best. There are three classes defined:
+"Bulk traffic", for large amounts of packets of normal size; "Low latency",
+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.
+
+CAUTION: If you are using the Intel(R) PRO/1000 CT Network Connection
+ (controller 82547), setting InterruptThrottleRate to a value
+ greater than 75,000, may hang (stop transmitting) adapters
+ 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 InterruptThrottleRate is set no greater
+ than 75,000 and is not set to 0.
+
+NOTE: When e1000 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 e1000 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.
+
+RxDescriptors
+-------------
+Valid Range: 80-256 for 82542 and 82543-based adapters
+ 80-4096 for all other supported adapters
+Default Value: 256
+
+This value specifies the number of receive buffer descriptors allocated
+by the driver. Increasing this value allows the driver to buffer more
+incoming packets, at the expense of increased system memory utilization.
+
+Each descriptor is 16 bytes. A receive buffer is also allocated for each
+descriptor and can be either 2048, 4096, 8192, or 16384 bytes, depending
+on the MTU setting. The maximum MTU size is 16110.
+
+NOTE: MTU designates the frame size. It only needs to be set for Jumbo
+ Frames. Depending on the available system resources, the request
+ for a higher number of receive descriptors may be denied. In this
+ case, use a lower number.
+
+RxIntDelay
+----------
+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.
+
+RxAbsIntDelay
+-------------
+(This parameter is supported only on 82540, 82545 and later adapters.)
+Valid Range: 0-65535 (0=off)
+Default Value: 128
+
+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.
+
+Speed
+-----
+(This parameter is supported only on adapters with copper connections.)
+Valid Settings: 0, 10, 100, 1000
+Default Value: 0 (auto-negotiate at all supported speeds)
+
+Speed forces the line speed to the specified value in megabits per second
+(Mbps). If this parameter is not specified or is set to 0 and the link
+partner is set to auto-negotiate, the board will auto-detect the correct
+speed. Duplex should also be set when Speed is set to either 10 or 100.
+
+TxDescriptors
+-------------
+Valid Range: 80-256 for 82542 and 82543-based adapters
+ 80-4096 for all other supported adapters
+Default Value: 256
+
+This value is the number of transmit descriptors allocated by the driver.
+Increasing this value allows the driver to queue more transmits. Each
+descriptor is 16 bytes.
+
+NOTE: Depending on the available system resources, the request for a
+ higher number of transmit descriptors may be denied. In this case,
+ use a lower number.
+
+TxDescriptorStep
+----------------
+Valid Range: 1 (use every Tx Descriptor)
+ 4 (use every 4th Tx Descriptor)
+
+Default Value: 1 (use every Tx Descriptor)
+
+On certain non-Intel architectures, it has been observed that intense TX
+traffic bursts of short packets may result in an improper descriptor
+writeback. If this occurs, the driver will report a "TX Timeout" and reset
+the adapter, after which the transmit flow will restart, though data may
+have stalled for as much as 10 seconds before it resumes.
+
+The improper writeback does not occur on the first descriptor in a system
+memory cache-line, which is typically 32 bytes, or 4 descriptors long.
+
+Setting TxDescriptorStep to a value of 4 will ensure that all TX descriptors
+are aligned to the start of a system memory cache line, and so this problem
+will not occur.
+
+NOTES: Setting TxDescriptorStep to 4 effectively reduces the number of
+ TxDescriptors available for transmits to 1/4 of the normal allocation.
+ This has a possible negative performance impact, which may be
+ compensated for by allocating more descriptors using the TxDescriptors
+ module parameter.
+
+ There are other conditions which may result in "TX Timeout", which will
+ not be resolved by the use of the TxDescriptorStep parameter. As the
+ issue addressed by this parameter has never been observed on Intel
+ Architecture platforms, it should not be used on Intel platforms.
+
+TxIntDelay
+----------
+Valid Range: 0-65535 (0=off)
+Default Value: 64
+
+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
+-------------
+(This parameter is supported only on 82540, 82545 and later adapters.)
+Valid Range: 0-65535 (0=off)
+Default Value: 64
+
+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.
+
+XsumRX
+------
+(This parameter is NOT supported on the 82542-based adapter.)
+Valid Range: 0-1
+Default Value: 1
+
+A value of '1' indicates that the driver should enable IP checksum
+offload for received packets (both UDP and TCP) to the adapter hardware.
+
+Copybreak
+---------
+Valid Range: 0-xxxxxxx (0=off)
+Default Value: 256
+Usage: insmod e1000.ko copybreak=128
+
+Driver copies all packets below or equaling this size to a fresh RX
+buffer before handing it up the stack.
+
+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/e1000/parameters/copybreak
+
+SmartPowerDownEnable
+--------------------
+Valid Range: 0-1
+Default Value: 0 (disabled)
+
+Allows 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)
+
+This workaround skips resetting the PHY at shutdown for the initial
+silicon releases of ICH8 systems.
+
+Speed and Duplex Configuration
+==============================
+
+Three keywords are used to control the speed and duplex configuration.
+These keywords are Speed, Duplex, and AutoNeg.
+
+If the board uses a fiber interface, these keywords are ignored, and the
+fiber interface board only links at 1000 Mbps full-duplex.
+
+For copper-based boards, the keywords interact as follows:
+
+ The default operation is auto-negotiate. The board advertises all
+ supported speed and duplex combinations, and it links at the highest
+ common speed and duplex mode IF the link partner is set to auto-negotiate.
+
+ If Speed = 1000, limited auto-negotiation is enabled and only 1000 Mbps
+ is advertised (The 1000BaseT spec requires auto-negotiation.)
+
+ If Speed = 10 or 100, then both Speed and Duplex should be set. Auto-
+ negotiation is disabled, and the AutoNeg parameter is ignored. Partner
+ SHOULD also be forced.
+
+The AutoNeg parameter is used when more control is required over the
+auto-negotiation process. It should be used when you wish to control which
+speed and duplex combinations are advertised during the auto-negotiation
+process.
+
+The parameter may be specified as either a decimal or hexadecimal value as
+determined by the bitmap below.
+
+Bit position 7 6 5 4 3 2 1 0
+Decimal Value 128 64 32 16 8 4 2 1
+Hex value 80 40 20 10 8 4 2 1
+Speed (Mbps) N/A N/A 1000 N/A 100 100 10 10
+Duplex Full Full Half Full Half
+
+Some examples of using AutoNeg:
+
+ modprobe e1000 AutoNeg=0x01 (Restricts autonegotiation to 10 Half)
+ modprobe e1000 AutoNeg=1 (Same as above)
+ modprobe e1000 AutoNeg=0x02 (Restricts autonegotiation to 10 Full)
+ modprobe e1000 AutoNeg=0x03 (Restricts autonegotiation to 10 Half or 10 Full)
+ modprobe e1000 AutoNeg=0x04 (Restricts autonegotiation to 100 Half)
+ modprobe e1000 AutoNeg=0x05 (Restricts autonegotiation to 10 Half or 100
+ Half)
+ modprobe e1000 AutoNeg=0x020 (Restricts autonegotiation to 1000 Full)
+ modprobe e1000 AutoNeg=32 (Same as above)
+
+Note that when this parameter is used, Speed and Duplex must not be specified.
+
+If the link partner is forced to a specific speed and duplex, then this
+parameter should not be used. Instead, use the Speed and Duplex parameters
+previously mentioned to force the adapter to the same speed and duplex.
+
+Additional Configurations
+=========================
+
+ 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:
+
+ ifconfig eth<x> mtu 9000 up
+
+ This setting is not saved across reboots. It can be made permanent if
+ you add:
+
+ MTU=9000
+
+ to the file /etc/sysconfig/network-scripts/ifcfg-eth<x>. This example
+ applies to the Red Hat distributions; other distributions may store this
+ setting in a different location.
+
+ Notes:
+ Degradation in throughput performance may be observed in some Jumbo frames
+ environments. If this is observed, increasing the application's socket buffer
+ size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help.
+ See the specific application manual and /usr/src/linux*/Documentation/
+ networking/ip-sysctl.txt for more details.
+
+ - The maximum MTU setting for Jumbo Frames is 16110. This value coincides
+ with the maximum Jumbo Frames size of 16128.
+
+ - Using Jumbo frames at 10 or 100 Mbps is not supported and may result in
+ poor performance or loss of link.
+
+ - Adapters based on the Intel(R) 82542 and 82573V/E controller do not
+ support Jumbo Frames. These correspond to the following product names:
+ Intel(R) PRO/1000 Gigabit Server Adapter
+ Intel(R) PRO/1000 PM Network Connection
+
+ ethtool
+ -------
+ The driver utilizes the ethtool interface for driver configuration and
+ diagnostics, as well as displaying statistical information. The ethtool
+ version 1.6 or later is required for this functionality.
+
+ The latest release of ethtool can be found from
+ http://ftp.kernel.org/pub/software/network/ethtool/
+
+ 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 e1000 driver must be
+ loaded when shutting down or rebooting the system.
+
+Support
+=======
+
+For general information, go to the Intel support website at:
+
+ http://support.intel.com
+
+or the Intel Wired Networking project hosted by Sourceforge at:
+
+ http://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
Code Review / kvmfornfv.git / blobdiff