1 .\" Copyright (c) 2001-2003, Intel Corporation
2 .\" All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions are met:
7 .\" 1. Redistributions of source code must retain the above copyright notice,
8 .\" this list of conditions and the following disclaimer.
10 .\" 2. Redistributions in binary form must reproduce the above copyright
11 .\" notice, this list of conditions and the following disclaimer in the
12 .\" documentation and/or other materials provided with the distribution.
14 .\" 3. Neither the name of the Intel Corporation nor the names of its
15 .\" contributors may be used to endorse or promote products derived from
16 .\" this software without specific prior written permission.
18 .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 .\" POSSIBILITY OF SUCH DAMAGE.
30 .\" * Other names and brands may be claimed as the property of others.
32 .\" $FreeBSD: src/share/man/man4/em.4,v 1.30 2008/10/06 21:55:53 simon Exp $
40 .Nd "Intel(R) PRO/1000 Gigabit Ethernet adapter driver"
42 To compile this driver into the kernel,
43 place the following lines in your
44 kernel configuration file:
45 .Bd -ragged -offset indent
47 .Cd "device em # for em(4)"
48 .Cd "device emx # for emx(4)"
51 Alternatively, to load the driver as a
52 module at boot time, place the following lines in
54 .Bd -literal -offset indent
56 if_em_load="YES" # for em(4)
57 if_emx_load="YES" # for emx(4)
62 driver provides support for PCI Gigabit Ethernet adapters based on
63 the Intel 82540, 82541ER, 82541PI, 82542, 82543, 82544, 82545, 82546,
64 82546EB, 82546GB, 82547, 82571, 81572, 82573, 82574, I217 and I218
65 Ethernet controller chips.
66 The driver supports Transmit/Receive checksum offload
67 and Jumbo Frames on all but 82542-based adapters.
68 Furthermore it supports TCP segmentation offload (TSO) on PCI-E adapters.
74 driver for 82571, 82572, 82573, 82574, I217 and I218 Ethernet controller chips
75 that additionally supports Receive Side Scaling (RSS, 2 reception queues).
79 driver will try enabling 2 reception queues
80 if there are multiple CPUs on the system.
84 driver could be configured to enable 2 transmission queues.
88 driver only enables 1 transmission queue,
89 since enabling 2 transmission queues will require setting up context
90 descriptor for every packets requiring hardware transmission offloading,
91 which hurts tiny packet transmission performance.
93 if the workload is mainly bulk data
94 or hardware transmission offloading is rarely required,
95 extra transmission queue could be enabled to reduce contention on
97 2 transmission queues will only be used when
99 is enabled on the device.
100 If multiple transmission queues are used,
101 the round-robin arbitration is performed among the transmission queues.
102 It should be noted that
103 if both TSO and multiple transmission queues are used,
104 the round-robin arbitration between transmission queues is done
105 at the TSO packet boundary.
107 .\"For questions related to hardware requirements,
108 .\"refer to the documentation supplied with your Intel PRO/1000 adapter.
109 .\"All hardware requirements listed apply to use with
112 Support for Jumbo Frames is provided via the interface MTU setting.
113 Selecting an MTU larger than 1500 bytes with the
115 utility configures the adapter to receive and transmit Jumbo Frames.
116 The maximum MTU size for Jumbo Frames is 16114.
118 This driver version supports VLANs.
123 drivers support the following media types:
124 .Bl -tag -width ".Cm 10baseT/UTP"
126 Enables auto-negotiation for speed and duplex.
128 Sets 10Mbps operation.
135 Sets 100Mbps operation.
142 Sets 1000Mbps operation.
145 mode is supported at this speed.
147 Sets 1000Mbps operation.
150 mode is supported at this speed.
157 drivers support the following media options:
158 .Bl -tag -width ".Cm full-duplex"
160 Forces full-duplex operation
162 Forces half-duplex operation.
171 is not specified, the driver defaults to
174 For more information on configuring this device, see
186 driver supports Gigabit Ethernet adapters based on the Intel
187 82540, 82541ER, 82541PI, 82542, 82543, 82544, 82545, 82546, 82546EB,
188 82546GB, 82547, 82571, 82572, 82573, 82574, I217 and I218
193 Intel 82540EM Gigabit Ethernet Controller
195 Intel 82540EP Gigabit Ethernet Controller
197 Intel 82543GC Gigabit Ethernet Controller
199 Intel 82544 Gigabit Ethernet Controller
201 Intel 82544EI Gigabit Ethernet Controller
203 Intel 82545GM Gigabit Ethernet Controller
205 Intel 82546EB Gigabit Ethernet Controller
207 Intel 82547EI Gigabit Ethernet Controller
209 Intel 82547GI Gigabit Ethernet Controller
211 Intel 82567 Gigabit Ethernet Controller
213 Intel 82571EB Gigabit Ethernet Controller
215 Intel 82572EI Gigabit Ethernet Controller
217 Intel 82573E Gigabit Ethernet Controller
219 Intel 82573L Gigabit Ethernet Controller
221 Intel 82573V Gigabit Ethernet Controller
223 Intel 82574 Gigabit Ethernet Controller
225 Intel 82578 Gigabit Ethernet PHY
227 Intel 82579 Gigabit Ethernet Controller
229 Intel Ethernet Connection I217-LM
231 Intel Ethernet Connection I217-V
233 Intel Ethernet Connection I218-LM
235 Intel Ethernet Connection I218-V
237 Intel Gigabit CT Desktop Adapter
239 Intel PRO/1000 F Server Adapter
241 Intel PRO/1000 GT Quad Port Server Adapter
243 Intel PRO/1000 MF Dual Port Server Adapter
245 Intel PRO/1000 MF Server Adapter
247 Intel PRO/1000 MF Server Adapter (LX)
249 Intel PRO/1000 MT Dual Port Server Adapter
251 Intel PRO/1000 MT Quad Port Server Adapter
253 Intel PRO/1000 MT Server Adapter
255 Intel PRO/1000 PF Dual Port Server Adapter
257 Intel PRO/1000 PF Quad Port Server Adapter
259 Intel PRO/1000 PF Server Adapter
261 Intel PRO/1000 PT Dual Port Server Adapter
263 Intel PRO/1000 PT Quad Port Low Profile Server Adapter
265 Intel PRO/1000 PT Quad Port Server Adapter
267 Intel PRO/1000 PT Server Adapter
269 Intel PRO/1000 T Server Adapter
271 Intel PRO/1000 XT Low Profile Server Adapter
273 Intel PRO/1000 XT Server Adapter
278 driver supports Gigabit Ethernet adapters based on the Intel
279 82571, 82572, 82573, 82574, I217 and I218 controller chips.
281 Tunables can be set at the
283 prompt before booting the kernel or stored in
286 is the device unit number.
287 .Bl -tag -width "hw.em.int_throttle_ceil"
288 .It Va hw.em.int_throttle_ceil
289 Hardware interrupt throttling rate.
290 The default value is 6000Hz.
291 This tunable also applies to
294 has a per device tunable
295 .Va hw.emxY.int_throttle_ceil ,
296 which serves the same purpose.
298 Number of receive descriptors allocated by the driver.
299 The default value is 512.
300 The 82542 and 82543-based adapters can handle up to 256 descriptors,
301 while others can have up to 4096.
302 This tunable also applies to
305 has a per device tunable
307 which serves the same purpose.
309 Number of transmit descriptors allocated by the driver.
310 The default value is 512.
311 The 82542 and 82543-based adapters can handle up to 256 descriptors,
312 while others can have up to 4096.
313 This tunable also applies to
316 has a per device tunable
318 which serves the same purpose.
319 .It Va hw.em.msi.enable Va hw.emY.msi.enable
320 By default, the driver will use MSI if it is supported.
321 This behavior can be turned off by setting these tunable to 0.
322 These tunables also applies to
324 .It Va hw.emY.msi.cpu
326 it specifies the MSI's target CPU.
327 This tunable also applies to
329 .It Va hw.emY.irq.unshared
330 If legacy interrupt is used,
332 the driver assumes the interrupt could be shared.
333 Setting this tunable to 1 allows the driver to
334 perform certain optimization based on the knowledge
335 that the interrupt is not shared.
336 These tunables also applies to
338 .It Va hw.emx.rxr Va hw.emxY.rxr
339 This tunable specifies the number of reception queues could be enabled.
340 Maximum allowed value for these tunables is 2.
341 Setting these tunables to 0 allows the driver to enable reception
342 queues based on the number of CPUs.
343 The default value is 0.
344 .It Va hw.emx.txr Va hw.emxY.txr
345 These tunables only take effect on 82571 and 82572.
346 This tunable specifies the number of transmission queues could be enabled.
347 Maximum allowed value for these tunables is 2.
348 Setting these tunables to 0 allows the driver to enable transmission
349 queues based on the number of CPUs.
350 The default value is 1.
351 .It Va hw.emxY.npoll.rxoff
352 This tunable specifies the leading target CPU for reception queues
355 The value specificed must be aligned to the number of reception queues enabled
356 and must be less than the power of 2 number of CPUs.
357 .It Va hw.emxY.npoll.rxoff
358 This tunable specifies the leading target CPU for transmission queues
361 The value specificed must be aligned to the number of transmission queues
363 and must be less than the power of 2 number of CPUs.
366 A number of per-interface variables are implemented in the
373 .Bl -tag -width "int_throttle_ceil"
375 Number of reception descriptors enabled (read-only).
382 Number of transmission descriptors enabled (read-only).
388 .It Va int_throttle_ceil
390 .Va hw.em.int_throttle_ceil .
392 This value controls how many transmit descriptors should be consumed
393 by the hardware before the hardware generates a transmit interrupt.
394 The default value is 1/16 of the number of transmit descriptors.
397 is not used on the hardware and
398 the major part of the transmitted data are bulk data,
399 this value could safely be set to 1/2 of the number of transmit descriptors.
401 The number of transmission descriptors should be setup
402 before the hardware register is written.
403 Setting this value too high will have negative effect
404 on transmission timeliness.
405 Setting this value too low will hurt overall transmission due to
406 the frequent hardware register writing.
409 Number of reception queues enabled (read-only).
410 This sysctl only applies to
418 Number of transmission queues that can be enabled (read-only).
419 This sysctl only applies to
427 Number of transmission queues being used (read-only).
428 This sysctl only applies to
432 .Va hw.emxY.npoll.rxoff .
433 The set value will take effect the next time
435 is enabled on the device.
436 This sysctl only applies to
440 .Va hw.emxY.npoll.txoff .
441 The set value will take effect the next time
443 is enabled on the device.
444 This sysctl only applies to
448 .\"For general information and support,
449 .\"go to the Intel support website at:
450 .\".Pa http://support.intel.com .
452 .\"If an issue is identified with the released source code on the supported kernel
453 .\"with a supported adapter, email the specific information related to the
455 .\".Aq Mt freebsdnic@mailbox.intel.com .
467 device driver first appeared in
471 driver first appeared in
477 driver was written by
478 .An Intel Corporation Aq Mt freebsdnic@mailbox.intel.com .
482 driver was written by