DESCRIPTION
The bge driver provides support for various NICs based on the Broadcom BCM570x, 5714, 5721, 5750, 5751 and 5789 families of Gigabit Ethernet controller chips. All of these NICs are capable of 10, 100 and 1000Mbps speeds over CAT5 copper cable, except for the SysKonnect SK-9D41 which supports only 1000Mbps over multimode fiber. The BCM570x builds upon the technology of the Alteon Tigon II. It has two R4000 CPU cores and is PCI v2.2 and PCI-X v1.0 compliant. It supports IP, TCP and UDP checksum offload for both receive and transmit, multiple RX and TX DMA rings for QoS applications, rules-based receive filtering, and VLAN tag stripping/insertion as well as a 256-bit multicast hash filter. Additional features may be provided via value-add firmware updates. The BCM570x supports TBI (ten bit interface) and GMII transceivers, which means it can be used with either copper or 1000baseX fiber applications. Note however the device only supports a single speed in TBI mode.
Most BCM5700-based cards also use the Broadcom BCM5401 or BCM5411 10/100/1000 copper gigabit transceivers, which support autonegotiation of 10, 100 and 1000Mbps modes in full or half duplex.
The BCM570x also supports jumbo frames, which can be configured 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.
The bge driver supports the following media types:
