1.\" Copyright (c) 2008 Pyun YongHyeon 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: src/share/man/man4/jme.4,v 1.1 2008/05/27 01:59:17 yongari Exp $ 26.\" 27.Dd May 24, 2013 28.Dt JME 4 29.Os 30.Sh NAME 31.Nm jme 32.Nd JMicron Gigabit/Fast Ethernet driver 33.Sh SYNOPSIS 34To compile this driver into the kernel, 35place the following lines in your 36kernel configuration file: 37.Bd -ragged -offset indent 38.Cd "device miibus" 39.Cd "device jme" 40.Ed 41.Pp 42Alternatively, to load the driver as a 43module at boot time, place the following line in 44.Xr loader.conf 5 : 45.Bd -literal -offset indent 46if_jme_load="YES" 47.Ed 48.Sh DESCRIPTION 49The 50.Nm 51device driver provides support for JMicron JMC250 PCI Express 52Gigabit Ethernet controllers and JMicron JMC260 PCI Express Fast 53Ethernet controllers. 54.Pp 55All LOMs supported by the 56.Nm 57driver have TCP/UDP/IP checksum offload for both transmit and receive, 58TCP segmentation offload (TSO), 59receive side scaling (RSS), 60multiple vector MSI-X, 61hardware VLAN tag stripping/insertion features, 62.\" Wake On Lan (WOL) 63an interrupt coalescing/moderation mechanism as well as 64a 64-bit multicast hash filter. 65Up to 4 reception queues can be enabled. 66By default, the 67.Nm 68driver will try enabling as many reception queues as allowed by 69the number of CPUs in the system. 70.Pp 71The JMC250 also supports Jumbo Frames (up to 9216 bytes), which can be 72configured via the interface MTU setting. 73Selecting an MTU larger than 1500 bytes with the 74.Xr ifconfig 8 75utility configures the adapter to receive and transmit Jumbo Frames. 76.Pp 77The 78.Nm 79driver supports the following media types: 80.Bl -tag -width ".Cm 10baseT/UTP" 81.It Cm autoselect 82Enable autoselection of the media type and options. 83The user can manually override 84the autoselected mode by adding media options to 85.Xr rc.conf 5 . 86.It Cm 10baseT/UTP 87Set 10Mbps operation. 88.It Cm 100baseTX 89Set 100Mbps (Fast Ethernet) operation. 90.It Cm 1000baseT 91Set 1000baseT operation over twisted pair. 92.El 93.Pp 94The 95.Nm 96driver supports the following media options: 97.Bl -tag -width ".Cm full-duplex" 98.It Cm full-duplex 99Force full duplex operation. 100.It Cm half-duplex 101Force half duplex operation. 102.El 103.Pp 104For more information on configuring this device, see 105.Xr ifconfig 8 . 106The 107.Nm 108driver supports 109.Xr polling 4 . 110.Ss Loader Tunables 111By default, the driver will use MSI-X if it is supported. 112This behavior can be turned off by setting the following tunable: 113.Em ( X 114is the device unit number): 115.Bd -literal -offset indent 116hw.jme.msix.enable=0 117hw.jmeX.msix.enable=0 118.Ed 119.Pp 120If MSI-X is used, 121the transmission queue MSI-X's target CPU 122can be specified using the following tunable: 123.Bd -literal -offset indent 124hw.jmeX.msix.txoff 125.Ed 126.Pp 127The maximum allowed value for this tunable is 128the power of 2 number of CPUs minus one. 129.Pp 130If MSI-X is used, 131the reception queue MSI-Xs' leading target CPU 132can be specified using the following tunable: 133.Bd -literal -offset indent 134hw.jmeX.msix.rxoff 135.Ed 136.Pp 137The value specificed must be aligned to the number of reception queues enabled 138and must be less than the power of 2 number of CPUs. 139.Pp 140If MSI-X is disabled, 141the driver will use MSI if it is supported. 142This behavior can be turned off by setting the following tunable: 143.Bd -literal -offset indent 144hw.jme.msi.enable=0 145hw.jmeX.msi.enable=0 146.Ed 147.Pp 148If MSI is used, 149MSI's target CPU can be changed by the following tunable: 150.Bd -literal -offset indent 151hw.jmeX.msi.cpu 152.Ed 153.Pp 154The maximum allowed value for this tunable is the number of CPUs minus one. 155.Pp 156Number of reception queues that can be enabled: 157.Bd -literal -offset indent 158hw.jme.rx_ring_count 159hw.jmeX.rx_ring_count 160.Ed 161.Pp 162Maximum allowed value for these tunables is 4 163and it must be power of 2 aligned. 164Setting these tunables to 0 allows driver to enable as many reception queues 165as allowed by the number of CPUs. 166.Pp 167Number of reception descriptors that can be used: 168.Bd -literal -offset indent 169hw.jme.rx_desc_count 170hw.jmeX.rx_desc_count 171.Ed 172.Pp 173Maximum allowed value for these tunables is 1024. 174.Pp 175Number of transmission descriptors that can be used: 176.Bd -literal -offset indent 177hw.jme.tx_desc_count 178hw.jmeX.tx_desc_count 179.Ed 180.Pp 181Maximum allowed value for these tunables is 1024. 182.Pp 183.Xr polling 4 184reception queues' leading target CPU can be specified by the following tunable: 185.Bd -literal -offset indent 186hw.jmeX.npoll.rxoff 187.Ed 188.Pp 189The value specificed must be aligned to the number of reception queues enabled 190and must be less than the power of 2 number of CPUs. 191.Pp 192.Xr polling 4 193transmission queue's target CPU can be specified by the following tunable: 194.Bd -literal -offset indent 195hw.jmeX.npoll.txoff 196.Ed 197.Pp 198The maximum allowed value for this tunable is 199the power of 2 number of CPUs minus one. 200.Ss MIB Variables 201A number of per-interface variables are implemented in the 202.Va hw.jme Ns Em X 203branch of the 204.Xr sysctl 3 205MIB. 206.Bl -tag -width "rx_ring_count" 207.It Va tx_coal_to 208Maximum amount of time to delay for TX completion interrupt in 209units of 1us. 210The accepted range is 1 to 65535, the default is 250 (250us). 211.It Va tx_coal_pkt 212Maximum number of packets to fire TX completion interrupt. 213The accepted range is 0 to 255, the default is 128. 214Packet count based TX interrupt coalescing could be disabled 215by setting this variable to 0. 216.It Va rx_coal_to 217Maximum amount of time to delay for RX completion interrupt in 218units of 1us. 219The accepted range is 1 to 65535, the default is 150 (150us). 220.It Va rx_coal_pkt 221Maximum number of packets to fire RX completion interrupt. 222The accepted range is 0 to 255, the default is 64. 223Packet count based RX interrupt coalescing could be disabled 224by setting this variable to 0. 225.It Va rx_desc_count 226Number of RX descriptors per-ring (read-only). 227Use the tunable 228.Va hw.jme.rx_desc_count 229to configure it. 230.It Va tx_desc_count 231Number of TX descriptors (read-only). 232Use the tunable 233.Va hw.jme.tx_desc_count 234to configure it. 235.It Va rx_ring_count 236Number of RX rings (read-only). 237Use the tunable 238.Va hw.jme.rx_ring_count 239to configure it. 240.It Va tx_wreg 241The number of transmission descriptors should be setup 242before the hardware register is written. 243Setting this value too high will have negative effect on 244transmission timeliness. 245Setting this value too low will hurt overall transmission 246due to the frequent hardware register writing. 247.It Va npoll_rxoff 248.Xr polling 4 249reception queues' leading target CPU. 250It has the same constraints as the tunable 251.Va hw.jmeX.npoll.rxoff . 252The set value will take effect the next time 253.Xr polling 4 254is enabled on the device. 255.It Va npoll_txoff 256.Xr polling 4 257transmission queue's target CPU. 258It has the same constraints as the tunable 259.Va hw.jmeX.npoll.txoff . 260The set value will take effect the next time 261.Xr polling 4 262is enabled on the device. 263.El 264.Sh SEE ALSO 265.Xr altq 4 , 266.Xr arp 4 , 267.Xr ifmedia 4 , 268.Xr miibus 4 , 269.Xr netintro 4 , 270.Xr ng_ether 4 , 271.Xr polling 4 , 272.Xr vlan 4 , 273.Xr ifconfig 8 274.Sh HISTORY 275The 276.Nm 277driver was written by 278.An Pyun YongHyeon Aq Mt yongari@FreeBSD.org . 279It first appeared in 280.Fx 7.1 281and was imported into 282.Dx 2.1 . 283.An Sepherosa Ziehau 284added the receive side scaling and 285multiple vector MSI-X support to 286.Dx . 287