if_rge: initial import of if_rge driver from OpenBSD.

This is an initial import of the if_rge driver from OpenBSD
and adapted to FreeBSD.

Differential Revision:	https://reviews.freebsd.org/D54101

share/man/man4/Makefile

@@ -501,6 +501,7 @@ MAN=	aac.4 \
 	random.4 \
 	rctl.4 \
 	re.4 \
+	rge.4 \
 	rgephy.4 \
 	rights.4 \
 	rl.4 \

share/man/man4/rge.4

@@ -0,0 +1,165 @@
+.\"
+.\" Copyright (c) 2025 Adrian Chadd <adrian@FreeBSD.org>
+.\"
+.\" SPDX-License-Identifier: BSD-2-Clause
+.\"
+.Dd December 12, 2025
+.Dt RGE 4
+.Os
+.Sh NAME
+.Nm rge
+.Nd RealTek RTL8125/RTL8126/RTL8127/Killer E3000 PCIe Ethernet adapter driver
+.Sh SYNOPSIS
+To compile this driver into the kernel,
+place the following lines in your
+kernel configuration file:
+.Bd -ragged -offset indent
+.Cd "device rge"
+.Ed
+.Pp
+Alternatively, to load the driver as a
+module at boot time, place the following line in
+.Xr loader.conf 5 :
+.Bd -literal -offset indent
+if_rge_load="YES"
+.Ed
+.Sh DESCRIPTION
+The
+.Nm
+driver provides support for various NICs based on the RealTek RTL8125,
+RTL8126 and RTL8127 PCIe Ethernet controllers.
+.Pp
+All of the NICs supported by this driver support 10, 100 and 1000Mbit
+over CAT5 cable.
+NICs based on the RTL8125 additionally support 2.5Gbit over CAT6 cable.
+NICs based on the RTL8126 additionally support 2.5Gbit and 5Gbit over CAT6
+cable.
+NICs based on the RTL8127 additionally support 2.5Gbit, 5Gbit and 10Gbit
+over CAT6 cable.
+.Pp
+All NICs supported by the
+.Nm
+driver have TCP/IP checksum offload and hardware VLAN tagging/insertion
+features, and use a descriptor-based DMA mechanism.
+They are also
+capable of TCP large send (TCP segmentation offload).
+.Pp
+The RTL8125, RTL8126 and RTL8127 devices are single-chip solutions combining
+both a MAC and PHY.
+Standalone cards are available in 1x PCIe models.
+.Pp
+The RTL8125, RTL8126 and RTL8127 also support jumbo frames, which can be
+configured via the interface MTU setting.
+The MTU is limited to 9126.
+Selecting an MTU larger than 1500 bytes with the
+.Xr ifconfig 8
+utility configures the adapter to receive and transmit jumbo frames.
+.Pp
+The
+.Nm
+driver supports the following media types:
+.Bl -tag -width "10baseT/UTP"
+.It Cm autoselect
+Enable autoselection of the media type and options.
+The user can manually override
+the autoselected mode by adding media options to
+.Xr rc.conf 5 .
+.It Cm 10baseT/UTP
+Set 10Mbps operation.
+The
+.Xr ifconfig 8
+.Cm mediaopt
+option can also be used to select either
+.Cm full-duplex
+or
+.Cm half-duplex
+modes.
+.It Cm 100baseTX
+Set 100Mbps (Fast Ethernet) operation.
+The
+.Xr ifconfig 8
+.Cm mediaopt
+option can also be used to select either
+.Cm full-duplex
+or
+.Cm half-duplex
+modes.
+.It Cm 1000baseTX
+Set 1000baseTX operation over twisted pair.
+The RealTek gigE chips support 1000Mbps in
+.Cm full-duplex
+mode only.
+.It Cm 2500baseTX
+Set 2500baseTX operation over twisted pair.
+The RealTek devices support 2.5Gbit in
+.Cm full-duplex
+mode only.
+.It Cm 5000baseTX
+Set 5000baseTX operation over twisted pair.
+The RealTek devices support 5Gbit in
+.Cm full-duplex
+mode only.
+.It Cm 10000baseTX
+Set 10000baseTX operation over twisted pair.
+The RealTek devices support 10Gbit in
+.Cm full-duplex
+mode only.
+.El
+.Pp
+The
+.Nm
+driver supports the following media options:
+.Bl -tag -width "full-duplex"
+.It Cm full-duplex
+Force full duplex operation.
+.It Cm half-duplex
+Force half duplex operation.
+.El
+.Pp
+For more information on configuring this device, see
+.Xr ifconfig 8 .
+.Sh HARDWARE
+The
+.Nm
+driver supports RealTek RTL8125, RTL8126, RTL8125 and Killer E3000 based
+PCIe 1GB to 1GB Ethernet devices.
+.Sh SYSCTL VARIABLES
+The following variables are available as both
+.Xr sysctl 8
+variables and
+.Xr loader 8
+tunables:
+.Bl -tag -width "xxxxxx"
+.It Va dev.rge.%d.debug
+Configure runtime debug output.  This is a 32 bit bitmask.
+.El
+.Sh DIAGNOSTICS
+.Bl -diag
+.It "rge%d: watchdog timeout"
+The device has stopped responding to the network, or there is a problem with
+the network connection (cable).
+.El
+.Sh SEE ALSO
+.Xr altq 4 ,
+.Xr arp 4 ,
+.Xr miibus 4 ,
+.Xr netintro 4 ,
+.Xr ng_ether 4 ,
+.Xr polling 4 ,
+.Xr vlan 4 ,
+.Xr ifconfig 8
+.Rs
+.%U https://www.realtek.com/
+.Re
+.Sh HISTORY
+The
+.Nm
+device driver first appeared in
+.Fx 16.0 .
+.Sh AUTHORS
+The
+.Nm
+driver was written by
+.An Kevin Lo Aq Mt kevlo@openbsd.org
+and ported to FreeBSD by
+.An Adrian Chadd Aq Mt adrian@freebsd.org .