NAME
gem
- ERI/GEM/GMAC Ethernet device driver
SYNOPSIS
gem* at pci? dev ? function ?
gem* at sbus? slot ? offset ?
Configuration of PHYs may also be necessary.
See
mii(4).
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 many Sun UltraSPARCs.
Cards supported by this driver include:
-
Sun GEM gigabit ethernet (SX fibre variants)
-
Sun ERI 10/100
-
Apple GMAC
The GEM family supports hardware checksumming to assist in computing
IPv4 TCP checksums.
The
gem
driver supports this feature of the chip.
See
ifconfig(8)
for information on how to enable this feature.
SEE ALSO
bmtphy(4),
ifmedia(4),
intro(4),
mii(4),
ifconfig(8)
HISTORY
The
gem
device driver appeared in
NetBSD1.6.
Support for PCI SX fibre cards was added in
NetBSD4.1.
Support for SBus SX fibre cards was added in
NetBSD5.0.
AUTHORS
The
gem
driver was written by
Eduardo Horvath
<eeh@NetBSD.org>.
SX fibre support was added by
Julian Coleman
<jdc@NetBSD.org>.
The man page was written by
Thomas Klausner
<wiz@NetBSD.org>.
BUGS
The hardware checksumming support does not support IPv4 UDP, although this was
allowed prior to
NetBSD5.0.
Also, the hardware IPv4 TCP receive checksumming support has bugs, so this is
disabled.
On the SX fibre variants of the hardware, the link will stay down if there is
a duplex mismatch.
Also, packet transmission may fail when in
half-duplex
mode.