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CXGB(4)                FreeBSD Kernel Interfaces Manual                CXGB(4)

     cxgb - Chelsio T3 10 Gigabit Ethernet adapter driver

     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           device firmware
           device cxgb

     To load the driver as a module at boot time, place the following line in


     The cxgb driver supports Transmit/Receive checksum offload, Jumbo Frames,
     TCP segmentation offload (TSO), Large Receive Offload (LRO), VLAN
     hardware insertion / extraction, and VLAN checksum offload.  For further
     hardware information, see

     For questions related to hardware requirements, refer to the
     documentation supplied with your Chelsio T3 adapter.  All hardware
     requirements listed apply to use with FreeBSD.

     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.  The maximum
     MTU size for Jumbo Frames is 9000.

     For more information on configuring this device, see ifconfig(8).

     The cxgb driver supports 10 Gigabit and 1 Gigabit Ethernet adapters based
     on the T3 and T3B chipset:

        Chelsio 10GBase-CX4
        Chelsio 10GBase-LR
        Chelsio 10GBase-SR

     Tunables can be set at the loader(8) prompt before booting the kernel or
     stored in loader.conf(5).

     cxgb%d: Unable to allocate bus resource: memory  A fatal initialization
     error has occurred.

     cxgb%d: Unable to allocate bus resource: interrupt  A fatal
     initialization error has occurred.

     cxgb%d: Could not find firmware image %s  The appropriate firmware kld
     module was not installed.  This is a fatal initialization error.

     For general information and support, go to the Chelsio support website

     If an issue is identified with the released source code on the supported
     kernel with a supported adapter, email the specific information related
     to the issue to <[email protected]>.

     altq(4), arp(4), netintro(4), ng_ether(4), ifconfig(8)

     The cxgb device driver first appeared in FreeBSD 6.3 and FreeBSD 7.0.

     The cxgb driver was written by Kip Macy <[email protected]> with
     substantial support from Scott Long <[email protected]>.

FreeBSD 11.1-RELEASE-p4         March 14, 2007         FreeBSD 11.1-RELEASE-p4
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