| GEM(4) | Device Drivers Manual | GEM(4) | 
gem —
gem* at pci? dev ? function ?
gem* at sbus? slot ? offset ?
Configuration of PHYs may also be necessary. See mii(4).
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:
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.
Sun Microsystems, GEM Gigabit Ethernet ASIC Specification, http://www.sun.com/processors/manuals/ge.pdf.
Sun Microsystems, Sbus GEM Specification, http://mediacast.sun.com/users/Barton808/media/gem_sbus-1.pdf.
gem device driver appeared in
  NetBSD 1.6. Support for PCI SX fibre cards was added
  in NetBSD 5.0. Support for SBus SX fibre cards was
  added in NetBSD 5.0.
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⟩.
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.
| June 2, 2018 | NetBSD 9.4 |