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JME(4)                       Device Drivers Manual                      JME(4)

NAME
     jme - JMicron Technologies JMC250 Gigabit Ethernet and JMC260 Fast
     Ethernet controller driver

SYNOPSIS
     jme* at pci? dev ? function ?

     Configuration of PHYs is necessary.  See mii(4).

DESCRIPTION
     The jme device driver supports network adapters based on the JMicron
     Technologies JMC250 Gigabit Ethernet and JMC260 Fast Ethernet chips.  The
     following features are supported:

           IPv4 transmit/receive IP/TCP/UDP checksum offload
           IPv6 transmit TCP/UDP checksum offload
           IPv4 and IPv6 TCP segmentation offload
           VLAN tag insertion/removal
           Interrupt coalescing
           10/100/1000Mbps operation in full-duplex mode
           10/100Mbps operation in half-duplex mode
           Jumbo frames (up to 9022 bytes)

     Due to hardware limitation checksums and TCP segmentation offload can't
     be enabled if the configured MTU is larger than 4000 bytes.

     Interrupt coalescing can be controlled on a per-adapter basis through the
     following sysctls:

     hw.jme.jme<x>.int_rxtos      jme receive interrupt moderation timer, in
                                  microseconds (defaults to 100)

     hw.jme.jme<x>.int_rxct       jme receive interrupt moderation packet
                                  counter (defaults to 128)

     hw.jme.jme<x>.int_txto       jme transmit interrupt moderation timer, in
                                  microseconds (defaults to 100)

     hw.jme.jme<x>.int_txct       jme transmit interrupt moderation packet
                                  counter (defaults to 128)

SEE ALSO
     ifmedia(4), jmphy(4), mii(4), netintro(4), pci(4), ifconfig(8)

HISTORY
     The jme device driver first appeared in NetBSD 5.0.

BUGS
     Hardware bugs prevent support of IPv6 receive TCP/UDP checksum offload in
     the JMC250 rev A2, and is disabled in the driver.  This should be
     revisited when a newer hardware revision is available.

NetBSD 10.99                   October 30, 2019                   NetBSD 10.99