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diff --git a/Documentation/networking/e1000.txt b/Documentation/networking/e1000.txt new file mode 100644 index 00000000000..2ebd4058d46 --- /dev/null +++ b/Documentation/networking/e1000.txt @@ -0,0 +1,401 @@ +Linux* Base Driver for the Intel(R) PRO/1000 Family of Adapters +=============================================================== + +November 17, 2004 + + +Contents +======== + +- In This Release +- Identifying Your Adapter +- Command Line Parameters +- Speed and Duplex Configuration +- Additional Configurations +- Known Issues +- Support + + +In This Release +=============== + +This file describes the Linux* Base Driver for the Intel(R) PRO/1000 Family +of Adapters, version 5.x.x. + +For questions related to hardware requirements, refer to the documentation +supplied with your Intel PRO/1000 adapter. All hardware requirements listed +apply to use with Linux. + +Native VLANs are now available with supported kernels. + +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/network/adapter/pro100/21397.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://downloadfinder.intel.com/scripts-df/support_intel.asp + +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 or insmod command +using this syntax: + + modprobe e1000 [<option>=<VAL1>,<VAL2>,...] + + insmod e1000 [<option>=<VAL1>,<VAL2>,...] + +For example, with two PRO/1000 PCI adapters, entering: + + insmod e1000 TxDescriptors=80,128 + +loads the e1000 driver with 80 TX descriptors for the first adapter and 128 TX +descriptors for the second adapter. + +The default value for each parameter is generally the recommended setting, +unless otherwise noted. Also, if the driver is statically built into the +kernel, the driver is loaded with the default values for all the parameters. +Ethtool can be used to change some of the parameters at runtime. + + 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 + + A descriptor describes a data buffer and attributes related to the + data buffer. This information is accessed by the hardware. + +AutoNeg (adapters using copper connections only) +Valid Range: 0x01-0x0F, 0x20-0x2F +Default Value: 0x2F + This parameter is a bit mask that specifies which speed and duplex + settings the board advertises. 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 (adapters using copper connections only) +Valid Range: 0-2 (0=auto-negotiate, 1=half, 2=full) +Default Value: 0 + 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: Read flow control settings from the EEPROM + This parameter controls the automatic generation(Tx) and response(Rx) to + Ethernet PAUSE frames. + +InterruptThrottleRate +Valid Range: 100-100000 (0=off, 1=dynamic) +Default Value: 8000 + This value represents the maximum number of interrupts per second the + controller generates. InterruptThrottleRate is another setting used in + interrupt moderation. Dynamic mode uses a heuristic algorithm to adjust + InterruptThrottleRate based on the current traffic load. +Un-supported Adapters: InterruptThrottleRate is NOT supported by 82542, 82543 + or 82544-based adapters. + + 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 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: + + insmod e1000.o 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 is the number of receive descriptors allocated by the driver. + Increasing this value allows the driver to buffer more incoming packets. + Each descriptor is 16 bytes. A receive buffer is allocated for each + descriptor and can either be 2048 or 4096 bytes long, depending on the MTU + + setting. An incoming packet can span one or more receive descriptors. + The maximum MTU size is 16110. + + NOTE: MTU designates the frame size. It only needs to be set for Jumbo + Frames. + NOTE: 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 (82540, 82545 and later adapters only) +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 (adapters using copper connections only) +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. + +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 (82540, 82545 and later adapters only) +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 (not available 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. + +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. When this parameter is used, Speed and Duplex parameters +must not be specified. The following table describes supported values for the +AutoNeg parameter: + +Speed (Mbps) 1000 100 100 10 10 +Duplex Full Full Half Full Half +Value (in base 16) 0x20 0x08 0x04 0x02 0x01 + +Example: insmod e1000 AutoNeg=0x03, loads e1000 and specifies (10 full duplex, +10 half duplex) for negotiation with the peer. + +Note that setting AutoNeg does not guarantee that the board will link at the +highest specified speed or duplex mode, but the board will link at the +highest possible speed/duplex of the link partner IF the link partner is also +set to auto-negotiate. If the link partner is forced speed/duplex, the +adapter MUST be forced to the same speed/duplex. + + +Additional Configurations +========================= + + Configuring the Driver on Different Distributions + ------------------------------------------------- + + Configuring a network driver to load properly when the system is started is + distribution dependent. Typically, the configuration process involves adding + an alias line to /etc/modules.conf as well as editing other system startup + scripts and/or configuration files. Many popular Linux distributions ship + with tools to make these changes for you. To learn the proper way to + configure a network device for your system, refer to your distribution + documentation. If during this process you are asked for the driver or module + name, the name for the Linux Base Driver for the Intel PRO/1000 Family of + Adapters is e1000. + + As an example, if you install the e1000 driver for two PRO/1000 adapters + (eth0 and eth1) and set the speed and duplex to 10full and 100half, add the + following to modules.conf: + + alias eth0 e1000 + alias eth1 e1000 + options e1000 Speed=10,100 Duplex=2,1 + + 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 + ------------ + + The driver supports Jumbo Frames for all adapters except 82542-based + adapters. 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 ethx mtu 9000 up + + The maximum MTU setting for Jumbo Frames is 16110. This value coincides + with the maximum Jumbo Frames size of 16128. + + NOTE: Jumbo Frames are supported at 1000 Mbps only. Using Jumbo Frames at + 10 or 100 Mbps may result in poor performance or loss of link. + + + NOTE: MTU designates the frame size. To enable Jumbo Frames, increase the + MTU size on the interface beyond 1500. + + Ethtool + ------- + + The driver utilizes the ethtool interface for driver configuration and + diagnostics, as well as displaying statistical information. Ethtool + version 1.6 or later is required for this functionality. + + The latest release of ethtool can be found from + http://sf.net/projects/gkernel. + + NOTE: Ethtool 1.6 only supports a limited set of ethtool options. Support + for a more complete ethtool feature set can be enabled by upgrading + ethtool to ethtool-1.8.1. + + Enabling Wake on LAN* (WoL) + --------------------------- + + WoL is configured through the Ethtool* utility. Ethtool is included with + all versions of Red Hat after Red Hat 7.2. For other Linux distributions, + download and install Ethtool from the following website: + http://sourceforge.net/projects/gkernel. + + For instructions on enabling WoL with Ethtool, refer to the website listed + above. + + 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. + + NAPI + ---- + + NAPI (Rx polling mode) is supported in the e1000 driver. NAPI is enabled + or disabled based on the configuration of the kernel. + + See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI. + + +Known Issues +============ + + Jumbo Frames System Requirement + ------------------------------- + + Memory allocation failures have been observed on Linux systems with 64 MB + of RAM or less that are running Jumbo Frames. If you are using Jumbo Frames, + your system may require more than the advertised minimum requirement of 64 MB + of system memory. + + +Support +======= + +For general information, go to the Intel support website at: + + http://support.intel.com + +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 linux.nics@intel.com. + + +License +======= + +This software program is released under the terms of a license agreement +between you ('Licensee') and Intel. Do not use or load this software or any +associated materials (collectively, the 'Software') until you have carefully +read the full terms and conditions of the LICENSE located in this software +package. By loading or using the Software, you agree to the terms of this +Agreement. If you do not agree with the terms of this Agreement, do not +install or use the Software. + +* Other names and brands may be claimed as the property of others. |