Fix up the sis.4 man page per Sheldon Hearn:

*   Clear the Os macro, which is assumed gracefully at run-off time.
    *   Use quotes to reduce the long name description (Nd) to a single
        argument.
    *   Use meaningful arguments to the -width option of the Bl macro.
    *   Mark rc.conf up with Xr instead of Pa so that it is obvious that
        further help on that file is available.
    *   Explicitly indicate that mediaopt is a command modifier (Cm) of
        the ifconfig(8) utility.
    *   Do not mark up half-duplex and full-duplex as arguments (Ar),
        since they are allowed values for an argument.
    *   Fix various grammar and spelling mistakes.

share/man/man4/sis.4

@@ -32,11 +32,10 @@
 .\"
 .Dd September 4, 1999
 .Dt SIS 4
-.Os FreeBSD
+.Os
 .Sh NAME
 .Nm sis
-.Nd
-SiS 900, SiS 7016 and NS DP83815 fast ethernet device driver
+.Nd "SiS 900, SiS 7016 and NS DP83815 fast ethernet device driver"
 .Sh SYNOPSIS
 .Cd "device miibus"
 .Cd "device sis"
@@ -68,29 +67,31 @@ The
 .Nm
 driver supports the following media types:
 .Pp
-.Bl -tag -width xxxxxxxxxxxxxxxxxxxx
+.Bl -tag -width 10baseTXUTP
 .It autoselect
 Enable autoselection of the media type and options.
 The user can manually override
-the autoselected mode by adding media options to the
-.Pa /etc/rc.conf
-fine.
+the autoselected mode by adding media options to
+.Xr rc.conf 5 .
 .It 10baseT/UTP
 Set 10Mbps operation.
 The
-.Ar mediaopt
+.Xr ifconfig 8
+.Cm mediaopt
 option can also be used to select either
-.Ar full-duplex
+.Sq full-duplex
 or
-.Ar half-duplex modes.
+.Sq half-duplex
+modes.
 .It 100baseTX
 Set 100Mbps (fast ethernet) operation.
 The
-.Ar mediaopt
+.Xr ifconfig 8
+.Cm mediaopt
 option can also be used to select either
-.Ar full-duplex
+.Sq full-duplex
 or
-.Ar half-duplex
+.Sq half-duplex
 modes.
 .El
 .Pp
@@ -98,7 +99,7 @@ The
 .Nm
 driver supports the following media options:
 .Pp
-.Bl -tag -width xxxxxxxxxxxxxxxxxxxx
+.Bl -tag -width full-duplex
 .It full-duplex
 Force full duplex operation
 .It half-duplex
@@ -115,7 +116,7 @@ A fatal initialization error has occurred.
 A fatal initialization error has occurred.
 .It "sis%d: watchdog timeout"
 The device has stopped responding to the network, or there is a problem with
-the network connection (cable).
+the network connection (e.g. a cable fault).
 .It "sis%d: no memory for rx list"
 The driver failed to allocate an mbuf for the receiver ring.
 .It "sis%d: no memory for tx list"
@@ -124,24 +125,24 @@ allocating a pad buffer or collapsing an mbuf chain into a clusisr.
 .It "sis%d: chip is in D3 power state -- setting to D0"
 This message applies only to adapters which support power
 management.
-Some operating sysisms place the controller in low power
+Some operating systems place the controller in low power
 mode when shutting down, and some PCI BIOSes fail to bring the chip
 out of this state before configuring it.
 The controller loses all of
 its PCI configuration in the D3 state, so if the BIOS does not set
-it back to full power mode in time, it won't be able to configure it
+it back to full power mode in time, it will not be able to configure it
 correctly.
 The driver tries to detect this condition and bring
 the adapter back to the D0 (full power) state, but this may not be
 enough to return the driver to a fully operational condition.
 If
 you see this message at boot time and the driver fails to attach
-the device as a network interface, you will have to perform second
+the device as a network interface, you will have to perform a
 warm boot to have the device properly configured.
 .Pp
 Note that this condition only occurs when warm booting from another
-operating sysism.
-If you power down your sysism prior to booting
+operating system.
+If you power down your system prior to booting
 .Fx ,
 the card should be configured correctly.
 .El