NAME

       gem — ERI/GEM/GMAC Ethernet device driver

SYNOPSIS

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

             device miibus
             device gem

       Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

             if_gem_load="YES"

DESCRIPTION

       The  gem driver provides support for the GMAC Ethernet hardware found mostly in the last Apple PowerBooks
       G3s and most G4-based Apple hardware, as well as Sun UltraSPARC machines.

       All controllers supported by the gem driver have TCP checksum offload capability  for  both  receive  and
       transmit,  support  for  the  reception  and  transmission  of  extended frames for vlan(4) and a 512-bit
       multicast hash filter.

HARDWARE

       Chips supported by the gem driver include:

       •   Apple GMAC
       •   Sun ERI 10/100 Mbps Ethernet
       •   Sun GEM Gigabit Ethernet

       The following add-on cards are known to work with the gem driver at this time:

       •   Sun Gigabit Ethernet PCI 2.0/3.0 (GBE/P) (part no. 501-4373)
       •   Sun Gigabit Ethernet SBus 2.0/3.0 (GBE/S) (part no. 501-4375)

NOTES

       On sparc64 the gem driver respects the local-mac-address? system configuration variable which can be  set
       in  the  Open  Firmware  boot  monitor  using the setenv command or by eeprom(8).  If set to “false” (the
       default), the gem driver will use the system's default MAC address for all of its  devices.   If  set  to
       “true”,  the unique MAC address of each interface is used if present rather than the system's default MAC
       address.

       Supported interfaces having their own MAC address include the on-board Sun  ERI  10/100  Mbps  on  boards
       equipped with more than one Ethernet interface and the Sun Gigabit Ethernet 2.0/3.0 GBE add-on cards.

SEE ALSO

       altq(4), miibus(4), netintro(4), vlan(4), eeprom(8), ifconfig(8)

HISTORY

       The gem device driver appeared in NetBSD 1.6.  The first FreeBSD version to include it was FreeBSD 5.0.

AUTHORS

       The  gem  driver was written for NetBSD by Eduardo Horvath <eeh@NetBSD.org>.  It was ported to FreeBSD by
       Thomas Moestl <tmm@FreeBSD.org> and later on improved by Marius  Strobl  <marius@FreeBSD.org>.   The  man
       page was written by Thomas Klausner <wiz@NetBSD.org>.

Debian                                          December 25, 2009                                         GEM(4)