sdevice -- System Administration

Configure drivers included within kernel
/etc/conf/sdevice

File  sdevice  configures  the drivers  that  can  be  included within  the
COHERENT  kernel.  Command  idmkcoh reads  this file when  it builds  a new
COHERENT kernel, and uses the  information within it to configure the suite
of drivers it links into the kernel.

There is  one line within the  file for each type of  hardware device; if a
driver manipulates more than one type  of device, then it has one entry for
each  type  of  device  it  manipulates.   A  driver's  entry  within  file
/etc/conf/mdevice  indicates  how  many  entries  a  driver can  have  with
sdevice: if field 3 contains flag  `o', the device can have only one entry;
whereas if  field 3 does not  contain this flag, it can  have more than one
entry (although it is not required  to do so).  An entry that begins with a
pound sign `#' is a comment, and is ignored by idmkcoh.

Each entry within sdevice consists of ten fields, as follows:

1. Name
     This  gives the  name of  driver,  and must  match the  name given  in
     mdevice. It cannot exceed eight characters.

2. Included in Kernel?
     This  field indicates  whether the  driver  is to  be linked  into the
     kernel: `Y' indicates that it is, `N' that it is not.

3. Number of Units
     The  number of  the hardware  units that  this driver  can manipulate.
     Under COHERENT, this is always set to zero.

4. Interrupt Priority
     The device's  interrupt priority.  This must be a  value between 0 and
     8: zero indicates that this  device is not interrupt driven, whereas a
     value from 1 to 8 gives the interrupt priority.

5. Interrupt Type
     The  type of  interrupt  for this  device.   The legal  values are  as
     follows:

     0  This device is not interrupt driven.

     1  The device  is interrupt driven.  If the  driver controls more than
        one device, each requires a separate interrupt.

     2  The device  is interrupt driven.  If the  driver supports more than
        one device, all share the same interrupt.

     3  The device requires an interrupt line.  If the driver supports more
        than  one device,  all share the  same interrupt.   Multiple device
        drivers that the  same interrupt priority can share this interrupt;
        however, this requires special hardware support.

6. Interrupt Vector
     The interrupt vector  used by the device.  If field  5 is set to zero,
     this must be also.

7. Low I/O Address
     The low  I/O address  through which  the driver communicates  with the
     device.  Set this field to zero if it is not used.

8. High I/O Address
     The high  I/O address through  which the driver  communicates with the
     device.  Set this field to zero if it is not used.

9. Low Memory Address
     The low  address of memory  within the controller of  the device being
     manipulated.  Set this field to zero if it is not used.

10. High Memory Address
     The high  address of memory within the controller  of the device being
     manipulated.  Set this field to zero if it is not used.

Note that all COHERENT drivers current set fields 7 through 10 to zero.

For examples of settings for this, read the file itself.  For an example of
modifying this file  to add a new driver, see  the Lexicon entry for device
drivers.

See Also

Administering COHERENT,
device drivers,
mdevice,
mtune,
stune

© 2012 by Stephen A. Ness