RE(4) BSD Kernel Interfaces Manual RE(4)NAMEre — RealTek 8139C+/8169/816xS/811xS/8101E PCI/PCIe Ethernet adapter
driver
SYNOPSIS
device miibus
device re
Alternatively, to load the driver as a module at boot time, place the
following line in /boot/loader.conf:
if_re_load="YES"
DESCRIPTION
The re driver provides support for various NICs based on the RealTek
RTL8139C+, RTL8169, RTL8169S, RTL8110S, RTL8168S, RTL8111S and RTL8101E
PCI and PCIe ethernet controllers.
NICs based on the 8139C+ and 8101E are capable of 10 and 100Mbps speeds
over CAT5 cable. NICs based on the 8169, 816xS and 811xS are capable of
10, 100 and 1000Mbps operation.
All NICs supported by the re driver have TCP/IP checksum offload and
hardware VLAN tagging/insertion features, and use a descriptor-based DMA
mechanism. They are also capable of TCP large send (TCP segmentation off‐
load).
The 8139C+ is a single-chip solution combining both a 10/100 MAC and PHY.
The 8169 is a 10/100/1000 MAC only, requiring a GMII or TBI external PHY.
The 8169S and 8110S are single-chip devices containing both a 10/100/1000
MAC and 10/100/1000 copper PHY. Standalone 10/100/1000 cards are avail‐
able in both 32-bit PCI and 64-bit PCI models. The 8110S is designed for
embedded LAN-on-motherboard applications.
The 8169, 8169S and 8110S also support jumbo frames, which can be config‐
ured via the interface MTU setting. Selecting an MTU larger than 1500
bytes with the ifconfig(8) utility configures the adapter to receive and
transmit jumbo frames. The maximum MTU setting for Jumbo Frames is 7426.
This value coincides with the maximum Jumbo Frames size of 7440.
The re driver supports the following media types:
autoselect Enable autoselection of the media type and options. The
user can manually override the autoselected mode by adding
media options to rc.conf(5).
10baseT/UTP Set 10Mbps operation. The ifconfig(8) mediaopt option can
also be used to select either full-duplex or half-duplex
modes.
100baseTX Set 100Mbps (fast ethernet) operation. The ifconfig(8)
mediaopt option can also be used to select either
full-duplex or half-duplex modes.
1000baseT Set 1000baseT operation over twisted pair. The RealTek gigE
chips support 1000Mbps in full-duplex mode only.
The re driver supports the following media options:
full-duplex Force full duplex operation.
half-duplex Force half duplex operation.
For more information on configuring this device, see ifconfig(8). The re
driver supports polling(4).
MIB Variables
A number of per-interface variables are implemented in the hw.reX branch
of the sysctl(3) MIB.
rx_desc_count Number of RX descriptors (read-only). Use the tunable
hw.re.rx_desc_count to configure it.
tx_desc_count Number of TX descriptors (read-only). Use the tunable
hw.re.tx_desc_count to configure it.
imtype Interrupt moderation type. 0 means disable interrupt mod‐
eration. 1 means using simulated interrupt moderation
(default). 2 means using hardware interrupt moderation,
if hardware supports it. Due to lack of proper document,
hardware interrupt moderation (2) may not work as
expected.
sim_time If imtype is set to 1, it controls interrupt moderation
time (unit: 1us). It will not have any effect, if imtype
is 0 or 2. By default, it is set to 75us for PCIe con‐
trollers and 125us for PCI controllers.
hw_txtime If the controller does not support hardware interrupt mod‐
eration, then this sysctl node will not exist. If imtype
is set to 2, it controls TX interrupt moderation time
(unit: 25us). It will not have any effect, if imtype is 0
or 1. It is set to 5 (125us) by default. Due to lack of
chip document, it may not work reliably.
hw_rxtime If the controller does not support hardware interrupt mod‐
eration, then this sysctl node will not exist. If imtype
is set to 2, it controls RX interrupt moderation time
(unit: 25us). It will not have any effect, if imtype is 0
or 1. It is set to 2 (50us) by default. Due to lack of
chip document, it may not work reliably.
HARDWARE
The re driver supports RealTek RTL8139C+, RTL8169, RTL816xS, RTL811xS,
and RTL8101E based Fast Ethernet and Gigabit Ethernet adapters including:
· Alloy Computer Products EtherGOLD 1439E 10/100 (8139C+)
· Compaq Evo N1015v Integrated Ethernet (8139C+)
· Corega CG-LAPCIGT Gigabit Ethernet (8169S)
· D-Link DGE-528(T) Gigabit Ethernet (8169S)
· Gigabyte 7N400 Pro2 Integrated Gigabit Ethernet (8110S)
· LevelOne GNC-0105T (8169S)
· LinkSys EG1032 (32-bit PCI)
· PLANEX COMMUNICATIONS Inc. GN-1200TC (8169S)
· Xterasys XN-152 10/100/1000 NIC (8169)
DIAGNOSTICS
re%d: couldn't map ports A fatal initialization error has occurred.
re%d: couldn't map interrupt A fatal initialization error has occurred.
re%d: watchdog timeout The device has stopped responding to the network,
or there is a problem with the network connection (cable).
SEE ALSOarp(4), ifmedia(4), miibus(4), netintro(4), ng_ether(4), polling(4),
vlan(4), ifconfig(8)
RealTek Semiconductor RTL8139C+, RTL8169, RTL8169S and RTL8110S
datasheets, http://www.realtek.com.tw.
HISTORY
The re device driver first appeared in FreeBSD 5.2 and DragonFly 1.0.
AUTHORS
The re driver was written by Bill Paul ⟨wpaul@windriver.com⟩.
BUGS
The Xterasys XN-152 32-bit PCI NIC, which uses the RTL8169 MAC and Mar‐
vell 88E1000 PHY, has a defect that causes DMA corruption if the board is
plugged into a 64-bit PCI slot. The defect lies in the board design, not
the chip itself: the PCI REQ64# and ACK64# lines should be pulled high,
but they are not. The result is that the 8169 chip is tricked into per‐
forming 64-bit DMA transfers even though a 64-bit data path between the
NIC and the bus does not actually exist.
Unfortunately, it is not possible to correct this problem in software,
however it is possible to detect it. When the re driver is loaded, it
will run a diagnostic routine designed to validate DMA operation by plac‐
ing the chip in digital loopback mode and initiating a packet transmis‐
sion. If the card functions properly, the transmitted data will be echoed
back unmodified. If the echoed data is corrupt, the driver will print an
error message on the console and abort the device attach. The user should
insure the NIC is installed in a 32-bit PCI slot to avoid this problem.
BSD November 2, 2006 BSD
