Note: This obsolete driver was removed from the kernel in version
2.6.26.
sk98lin is the Gigabit Ethernet driver for Marvell and SysKonnect
network adapter cards. It supports SysKonnect SK-98xx/SK-95xx
compliant Gigabit Ethernet Adapter and any Yukon compliant
chipset.
When loading the driver using insmod, parameters for the network
adapter cards might be stated as a sequence of comma separated
commands. If for instance two network adapters are installed and
AutoNegotiation on Port A of the first adapter should be ON, but
on the Port A of the second adapter switched OFF, one must enter:
insmod sk98lin.o AutoNeg_A=On,Off
After sk98lin is bound to one or more adapter cards and the /proc
filesystem is mounted on your system, a dedicated statistics file
will be created in the folder /proc/net/sk98lin for all ports of
the installed network adapter cards. Those files are named
eth[x], where x is the number of the interface that has been
assigned to a dedicated port by the system.
If loading is finished, any desired IP address can be assigned to
the respective eth[x] interface using the ifconfig(8) command.
This causes the adapter to connect to the Ethernet and to display
a status message on the console saying "ethx: network connection
up using port y" followed by the configured or detected
connection parameters.
The sk98lin also supports large frames (also called jumbo
frames). Using jumbo frames can improve throughput tremendously
when transferring large amounts of data. To enable large frames,
the MTU (maximum transfer unit) size for an interface is to be
set to a high value. The default MTU size is 1500 and can be
changed up to 9000 (bytes). Setting the MTU size can be done
when assigning the IP address to the interface or later by using
the ifconfig(8) command with the mtu parameter. If for instance
eth0 needs an IP address and a large frame MTU size, the
following two commands might be used:
ifconfig eth0 10.1.1.1
ifconfig eth0 mtu 9000
Those two commands might even be combined into one:
ifconfig eth0 10.1.1.1 mtu 9000
Note that large frames can be used only if permitted by your
network infrastructure. This means, that any switch being used
in your Ethernet must also support large frames. Quite some
switches support large frames, but need to be configured to do
so. Most of the times, their default setting is to support only
standard frames with an MTU size of 1500 (bytes). In addition to
the switches inside the network, all network adapters that are to
be used must also be enabled regarding jumbo frames. If an
adapter is not set to receive large frames, it will simply drop
them.
Switching back to the standard Ethernet frame size can be done by
using the ifconfig(8) command again:
ifconfig eth0 mtu 1500
The Marvell/SysKonnect Gigabit Ethernet driver for Linux is able
to support VLAN and Link Aggregation according to IEEE standards
802.1, 802.1q, and 802.3ad. Those features are available only
after installation of open source modules which can be found on
the Internet:
VLAN: ⟨http://www.candelatech.com/~greear/vlan.html⟩
Link Aggregation: ⟨http://www.st.rim.or.jp/~yumo⟩
Note that Marvell/SysKonnect does not offer any support for these
open source modules and does not take the responsibility for any
kind of failures or problems arising when using these modules.
Parameters
Speed_A=i,j,...
This parameter is used to set the speed capabilities of
port A of an adapter card. It is valid only for Yukon
copper adapters. Possible values are: 10, 100, 1000, or
Auto; Auto is the default. Usually, the speed is
negotiated between the two ports during link
establishment. If this fails, a port can be forced to a
specific setting with this parameter.
Speed_B=i,j,...
This parameter is used to set the speed capabilities of
port B of an adapter card. It is valid only for Yukon
copper adapters. Possible values are: 10, 100, 1000, or
Auto; Auto is the default. Usually, the speed is
negotiated between the two ports during link
establishment. If this fails, a port can be forced to a
specific setting with this parameter.
AutoNeg_A=i,j,...
Enables or disables the use of autonegotiation of port A
of an adapter card. Possible values are: On, Off, or
Sense; On is the default. The Sense mode automatically
detects whether the link partner supports auto-negotiation
or not.
AutoNeg_B=i,j,...
Enables or disables the use of autonegotiation of port B
of an adapter card. Possible values are: On, Off, or
Sense; On is the default. The Sense mode automatically
detects whether the link partner supports auto-negotiation
or not.
DupCap_A=i,j,...
This parameter indicates the duplex mode to be used for
port A of an adapter card. Possible values are: Half,
Full, or Both; Both is the default. This parameter is
relevant only if AutoNeg_A of port A is not set to Sense.
If AutoNeg_A is set to On, all three values of DupCap_A (
Half, Full, or Both) might be stated. If AutoNeg_A is set
to Off, only DupCap_A values Full and Half are allowed.
This DupCap_A parameter is useful if your link partner
does not support all possible duplex combinations.
DupCap_B=i,j,...
This parameter indicates the duplex mode to be used for
port B of an adapter card. Possible values are: Half,
Full, or Both; Both is the default. This parameter is
relevant only if AutoNeg_B of port B is not set to Sense.
If AutoNeg_B is set to On, all three values of DupCap_B (
Half, Full, or Both) might be stated. If AutoNeg_B is set
to Off, only DupCap_B values Full and Half are allowed.
This DupCap_B parameter is useful if your link partner
does not support all possible duplex combinations.
FlowCtrl_A=i,j,...
This parameter can be used to set the flow control
capabilities the port reports during auto-negotiation.
Possible values are: Sym, SymOrRem, LocSend, or None;
SymOrRem is the default. The different modes have the
following meaning:
Sym = Symmetric
both link partners are allowed to send PAUSE frames
SymOrRem = SymmetricOrRemote
both or only remote partner are allowed to send PAUSE
frames
LocSend = LocalSend
only local link partner is allowed to send PAUSE frames
None = None
no link partner is allowed to send PAUSE frames
Note that this parameter is ignored if AutoNeg_A is set to
Off.
FlowCtrl_B=i,j,...
This parameter can be used to set the flow control
capabilities the port reports during auto-negotiation.
Possible values are: Sym, SymOrRem, LocSend, or None;
SymOrRem is the default. The different modes have the
following meaning:
Sym = Symmetric
both link partners are allowed to send PAUSE frames
SymOrRem = SymmetricOrRemote
both or only remote partner are allowed to send PAUSE
frames
LocSend = LocalSend
only local link partner is allowed to send PAUSE frames
None = None
no link partner is allowed to send PAUSE frames
Note that this parameter is ignored if AutoNeg_B is set to
Off.
Role_A=i,j,...
This parameter is valid only for 1000Base-T adapter cards.
For two 1000Base-T ports to communicate, one must take the
role of the master (providing timing information), while
the other must be the slave. Possible values are: Auto,
Master, or Slave; Auto is the default. Usually, the role
of a port is negotiated between two ports during link
establishment, but if that fails the port A of an adapter
card can be forced to a specific setting with this
parameter.
Role_B=i,j,...
This parameter is valid only for 1000Base-T adapter cards.
For two 1000Base-T ports to communicate, one must take the
role of the master (providing timing information), while
the other must be the slave. Possible values are: Auto,
Master, or Slave; Auto is the default. Usually, the role
of a port is negotiated between two ports during link
establishment, but if that fails the port B of an adapter
card can be forced to a specific setting with this
parameter.
ConType=i,j,...
This parameter is a combination of all five per-port
parameters within one single parameter. This simplifies
the configuration of both ports of an adapter card. The
different values of this variable reflect the most
meaningful combinations of port parameters. Possible
values and their corresponding combination of per-port
parameters:
ConType DupCap AutoNeg FlowCtrl Role Speed
Auto Both On SymOrRem Auto Auto
100FD Full Off None Auto 100
100HD Half Off None Auto 100
10FD Full Off None Auto 10
10HD Half Off None Auto 10
Stating any other port parameter together with this
ConType parameter will result in a merged configuration of
those settings. This is due to the fact, that the per-
port parameters (e.g., Speed_A) have a higher priority
than the combined variable ConType.
Moderation=i,j,...
Interrupt moderation is employed to limit the maximum
number of interrupts the driver has to serve. That is,
one or more interrupts (which indicate any transmit or
receive packet to be processed) are queued until the
driver processes them. When queued interrupts are to be
served, is determined by the IntsPerSec parameter, which
is explained later below. Possible moderation modes are:
None, Static, or Dynamic; None is the default. The
different modes have the following meaning:
None No interrupt moderation is applied on the adapter
card. Therefore, each transmit or receive interrupt is
served immediately as soon as it appears on the interrupt
line of the adapter card.
Static Interrupt moderation is applied on the adapter
card. All transmit and receive interrupts are queued
until a complete moderation interval ends. If such a
moderation interval ends, all queued interrupts are
processed in one big bunch without any delay. The term
Static reflects the fact, that interrupt moderation is
always enabled, regardless how much network load is
currently passing via a particular interface. In
addition, the duration of the moderation interval has a
fixed length that never changes while the driver is
operational.
Dynamic Interrupt moderation might be applied on the
adapter card, depending on the load of the system. If the
driver detects that the system load is too high, the
driver tries to shield the system against too much network
load by enabling interrupt moderation. If—at a later
time—the CPU utilization decreases again (or if the
network load is negligible), the interrupt moderation will
automatically be disabled.
Interrupt moderation should be used when the driver has to
handle one or more interfaces with a high network load,
which—as a consequence—leads also to a high CPU
utilization. When moderation is applied in such high
network load situations, CPU load might be reduced by
20–30% on slow computers.
Note that the drawback of using interrupt moderation is an
increase of the round-trip-time (RTT), due to the queuing
and serving of interrupts at dedicated moderation times.
IntsPerSec=i,j,...
This parameter determines the length of any interrupt
moderation interval. Assuming that static interrupt
moderation is to be used, an IntsPerSec parameter value of
2000 will lead to an interrupt moderation interval of 500
microseconds. Possible values for this parameter are in
the range of 30...40000 (interrupts per second). The
default value is 2000.
This parameter is used only if either static or dynamic
interrupt moderation is enabled on a network adapter card.
This parameter is ignored if no moderation is applied.
Note that the duration of the moderation interval is to be
chosen with care. At first glance, selecting a very long
duration (e.g., only 100 interrupts per second) seems to
be meaningful, but the increase of packet-processing delay
is tremendous. On the other hand, selecting a very short
moderation time might compensate the use of any moderation
being applied.
PrefPort=i,j,...
This parameter is used to force the preferred port to A or
B (on dual-port network adapters). The preferred port is
the one that is used if both ports A and B are detected as
fully functional. Possible values are: A or B; A is the
default.
RlmtMode=i,j,...
RLMT monitors the status of the port. If the link of the
active port fails, RLMT switches immediately to the
standby link. The virtual link is maintained as long as
at least one "physical" link is up. This parameters
states how RLMT should monitor both ports. Possible
values are: CheckLinkState, CheckLocalPort, CheckSeg, or
DualNet; CheckLinkState is the default. The different
modes have the following meaning:
CheckLinkState Check link state only: RLMT uses the link
state reported by the adapter hardware for each individual
port to determine whether a port can be used for all
network traffic or not.
CheckLocalPort In this mode, RLMT monitors the network
path between the two ports of an adapter by regularly
exchanging packets between them. This mode requires a
network configuration in which the two ports are able to
"see" each other (i.e., there must not be any router
between the ports).
CheckSeg Check local port and segmentation: This mode
supports the same functions as the CheckLocalPort mode and
additionally checks network segmentation between the
ports. Therefore, this mode is to be used only if Gigabit
Ethernet switches are installed on the network that have
been configured to use the Spanning Tree protocol.
DualNet In this mode, ports A and B are used as separate
devices. If you have a dual port adapter, port A will be
configured as eth[x] and port B as eth[x+1]. Both ports
can be used independently with distinct IP addresses. The
preferred port setting is not used. RLMT is turned off.
Note that RLMT modes CheckLocalPort and CheckLinkState are
designed to operate in configurations where a network path
between the ports on one adapter exists. Moreover, they
are not designed to work where adapters are connected
back-to-back.
