for connected embedded systems
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devnp-i82544.so
Driver for Intel 825* Gigabit Ethernet LAN adapters
Syntax:
io-pkt-variant -d i82544 [option[,option ...]] ... &
where variant is one of v4, v4-hc, or v6-hc.
Runs on:
Neutrino
Options:
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Use commas, not spaces, to separate the options. |
- did=0xXXXX
- Detect only devices with this specific PCI Device ID. The default is automatically detected on supported hardware.
- duplex=0|1
- Half (0) or full (1) duplex mode. The default is automatically
detected on supported hardware.
If you specify duplex, specify speed as well;
if duplex alone is specified, it is ignored and both speed and duplex
are auto-negotiated.
You can also use ifconfig -m and ifconfig wmX media to set this.
- irq=N
- IRQ of the interface. The default is automatically detected on supported hardware.
- irq_thresh=X
- The maximum number of interrupts per second to be generated. The default is 9000. This reduces CPU consumption by limiting how often interrupts occur, which is especially helpful on slower processors.
- mac=XXXXXXXXXXXX
- The MAC address of the controller. The default is automatically detected on supported hardware.
- nomulticast
- Disable the driver from sending or receiving multicast packets. By default, multicast is enabled.
- pause_rx_disable
- Disregard received pause (flow control) frames.
- pause_rx_enable
- Always act on received pause (flow control) frames.
- pause_tx_disable
- Never transmit pause (flow control) frames.
- pause_tx_enable
- Always transmit pause (flow control) frames.
- pci=0xXXXX
- Detect only devices at this specific PCI index.
- receive=num
- The number of receive descriptors; the default is 512.
- rx_abs=X
- The receive interrupt absolute delay time multiplier. The default is 92, and the maximum is 200.
- rx_delay=X
- The receive interrupt delay time multiplier (×1.024 ns). The default is 23, and the maximum is 50.
- speed=10|100|1000
- The media data rate (10Mbit, 100Mbit, or Gigabit operation).
The default is automatically detected on supported hardware.
If you specify speed, specify duplex as well;
if speed alone is specified, the specified speed is correctly set,
but duplex defaults to half (0).
You can also use ifconfig -m and ifconfig wmX media to set this.
- transmit=N
- The number of transmit descriptors; the default is 4096.
- verbose
verbose=num - Be verbose. Specify num for more verbosity (num can be 1-4; the higher the number, the more detailed the output). The output goes to slogger; invoke sloginfo to view it.
- vid=0xXXXX
- Detect only devices with this specific PCI Vendor ID.
Description:
The devnp-i82544.so driver manages the Intel 82540, 82541, 82544, 82545, 82546, 82547, 82571, and 82572 Gigabit Ethernet LAN adapters. This is a native io-pkt driver; its interface names are in the form wmX, where X is an integer.
The devnp-e1000.so and devnp-i82544.so drivers are similar:
- devnp-i82544.so has performance optimizations (TSO and interrupt thresholding options) that may make it a better performing candidate for some hardware
- devnp-e1000.so likely supports more hardware
Transmit Segmentation Offload (TSO) allows the stack to send very large TCP buffers down to the driver, and the driver takes care of carving them up into individual IP packets of the right size. This can greatly reduce the CPU usage for transmitting large amounts of data.
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If the device enumerators (see enum-devices) don't recognize your device, try explicitly specifying the device ID with the did option when you start the driver. |
Some devices support hardware checksums, although some might do so in only one direction; to determine if your device does, type:
ifconfig wmX
and look for the following in the list of supported options:
- ip4csum, ip4csum-rx, ip4csum-tx
- tcp4csum, tcp4csum-rx, tcp4csum-tx
- tcp6csum, tcp6csum-rx, tcp6csum-tx
- udp4csum, udp4csum-rx, udp4csum-tx
- udp6csum, udp6csum-rx, udp6csum-tx
You can then use ifconfig to enable or disable whichever of these options your device supports.
Examples:
Start io-pkt using the devnp-i82544.so driver and the full TCP/IP stack:
io-pkt -d i82544 -p tcpip ifconfig wm0 10.1.0.184
See also:
devn-*, devnp-*, ifconfig, io-pkt
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