dpt(HW)

dpt -- DPT SCSI host adapter subsystem

Description

The dpt host adapter subsystem enables SCSI target drivers (such as sd01 and st01) to communicate on the SCSI bus with target controllers and logical units. This driver implements the Storage Device Interface (SDI) for such SDI target drivers.

This driver supports hot insertion and removal of devices on the SCSI bus using the sdiadd(ADM) and sdirm(ADM) commands. It supports DPT WIDE SCSI controllers.

It is also possible for an application to access the SCSI bus subsystem directly by using the pass-through interface. See pt_open(S).

The DPT host adapter driver honors the command timeout values as specified in the scb structure; see the scb(D4sdi) manual page. A software watchdog timer enforces the processing time limit. When the watchdog timer detects a job that has exceeded its processing time limit, it attempts to abort the job with a SCSI Job Abort Message. The driver also enforces a time limit on the abort process, thereby ensuring that jobs that timeout are reported to the sending SDI Target Driver whether or not the abort succeeds.

NOTE: The DPT SCSI adapter will not work reliably with the Emulex SCSI/ESDI bridge controller (also known as the AT&T DCM/4E). In the future, a hardware or software solution might be implemented.

For ISA DPT controllers to work, the I/O ports must be set to secondary/disabled.

ioctl calls

The following command is supported:

B_REDT: reads the extended Equipped Device Table (EDT) data structure that is stored in the dpt driver's internal data structure

Files

/usr/include/sys/dpt.h
/usr/include/sys/scsi.h
/usr/include/sys/sdi.h
/usr/include/sys/sdi_edt.h
/etc/conf/pack.d/dpt/space.c

References

ioctl(S), sc01(HW), sd01(HW), sdi(HW), st01(HW), sw01(HW), wd7000(HW)

Notices

Extreme caution should be exercised when using the pass-through interface. It is possible to interfere with normal system I/O and cause hangs if pass-through is used to an active device. Pass-through should only be used to a device that is otherwise quiescent.