SK(4) | Kernel Interfaces Manual | SK(4) |
The msk driver provides support for the Marvell Yukon-2 based Gigabit Ethernet adapters, including the following:
The SysKonnect based adapters consist of two main components: the XaQti Corp. XMAC II Gigabit MAC (sk) and the SysKonnect GEnesis controller ASIC (skc). The XMAC provides the Gigabit MAC and PHY support while the GEnesis provides an interface to the PCI bus, DMA support, packet buffering and arbitration. The GEnesis can control up to two XMACs simultaneously, allowing dual-port NIC configurations.
The Marvell based adapters are a single integrated circuit, but are still presented as a separate MAC (sk) and controller ASIC (skc). At this time, there are no dual-port Marvell based NICs.
The sk driver configures dual port SysKonnect adapters such that each XMAC is treated as a separate logical network interface. Both ports can operate independently of each other and can be connected to separate networks. The SysKonnect driver software currently only uses the second port on dual port adapters for failover purposes: if the link on the primary port fails, the SysKonnect driver will automatically switch traffic onto the second port.
The XaQti XMAC II supports full and half duplex operation with autonegotiation. The XMAC also supports unlimited frame sizes. Support for jumbo frames is provided 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. Using jumbo frames can greatly improve performance for certain tasks, such as file transfers and data streaming.
Hardware TCP/IP checksum offloading for IPv4 is supported.
The following media types and options (as given to ifconfig(8)) are supported:
For more information on configuring this device, see ifconfig(8). To view a list of media types and options supported by the card, try ifconfig -m <device>. For example, ifconfig -m sk0.
XaQti XMAC II datasheet, http://www.xaqti.com.
SysKonnect GEnesis programming manual, http://www.syskonnect.com.
The msk driver first appeared in OpenBSD 4.0, and was ported to NetBSD 4.0.
Support for checksum offload is unimplemented.
Performance with at least some Marvell-based adapters is poor, especially on loaded PCI buses or when the adapters are behind PCI-PCI bridges. It is believed that this is because the Marvell parts have significantly less buffering than the original SysKonnect cards had.
September 9, 2006 | NetBSD 6.1 |