You can configure the wd driver using entries in
/etc/conf/cf.d/mdevice and /etc/conf/sdevice.d/wd.
Changes to these files
will only take effect if the kernel is relinked using
and the machine rebooted.
Configure wd driver-specific characteristics
by editing the /etc/conf/pack.d/wd/space.c file.
Boot-time configuration of ATAPI and IDE peripherals
ATAPI peripherals are similar to SCSI devices.
The system treats ATAPI peripherals as
SCSI devices on a host adapter named ``wd''.
Regular IDE hard disks are not ATAPI
devices and are not treated as SCSI devices.
Typically the system automatically recognizes ATAPI
peripherals. However, there may be times during
initial system load when it might be helpful to use the
Sdsk, Sflp, Srom, and Stpbootstring(HW)
parameters to tell the kernel about the ATAPI
devices on your system.
Specify the primary IDE
controller as wd host adapter number ``0''
and the secondary controller (if present) as adapter ``1''.
: defbootstr Stp=wd(1,0,0) Srom=wd(1,1,0)
This sequence of bootstrings specifies to use the default bootstring
and indicates to the kernel that an ATAPI tape drive
is on the secondary IDE controller in the master position
and that an ATAPI CD-ROM drive is on the
secondary IDE controller in the slave position.
The following list shows the types of devices
that have been tested with the ATAPI interface.
Sdsk peripheral driver and:
Sflp peripheral driver and:
LS120 and LS140 super floppy drives
Srom peripheral driver and:
CD-ROM writers and rewriters (using Open Source cdrecord)
a variety of DVD-ROM writers (using commercial backup software)
Stp peripheral driver and:
Seagate Travan tape drives
The wd driver supports the wd.noscanbootstring(HW),
which disables hardware checking by the driver.
This prevents conflicts on systems that have both SCSI
and ATAPI hardware enabled.
This bootstring is only required during installation.
Systems that include single types of mass storage devices (that
is, EIDE/ATAPI or SCSI only) do not need this
The wd.geom bootstring specifies the type of disk geometry
example: 16 Hds 63 Sectors n Cyl
example: 255 Hds 63 Sectors n Cyl
use either (may be limited to 8 GB)
The wd.geom bootstring will not override disk parameters
that have been written to the disk during a previous installation
or the use of
To forcefully remove disk parameters from a given drive, use this
There are two bootstrings that can be used to change the default
detection and setting of transfer modes for motherboards/controllers
not recognized by the driver. The wd.udma bootstring
has the following settings:
disables UDMA (forces PIO mode)
if settings do not match motherboard,
tries to sense and reprogram disk
0 or 16
udma 16 MB/sec
1 or 25
udma 25 MB/sec
2 or 33
udma 33 MB/sec
3 or 44
udma 44 MB/sec
4 or 66
udma 66 MB/sec
5 or 100
udma 100 MB/sec
6 or 133
udma 133 MB/sec
The wd.debug=udma bootstring displays the current
UDMA setting and values for motherboard and drives.
The wd driver
supports all standard SCSI ioctls
that are defined in the <sys/scsicmd.h> header file
and documented on the
for general information about kernel error messages,
including a list of generic device driver errors.