DPT(4) BSD Programmer's Manual DPT(4)NAMEdpt - Driver for DPT SCSI host bus adapters including the PM3021, PM3222,
PM3224 SmartRAID SCSI RAID adapters
SYNOPSIS
dpt0 at isa?
dpt0 at isa? port ? drq 5
dpt0 at eisa?
dpt0 at pci?
tg* at dpt?
DESCRIPTION
The dpt driver provides access to SCSI disks and disk arrays controlled
by DPT host bus adapters and SmartRAID SCSI RAID adapters through the
standard SCSI disk sd(4) interface. ISA, EISA and PCI adapter versions
are supported. Single or multiple channel adapters and hardware based
RAID arrays are supported. Software RAID (RAID drives spanning adapters)
is not supported.
The DPT ISA adapters use jumpers or BIOS configuration options to alter
the I/O address, interrupt level (IRQ) and DMA channel (DRQ) used by the
adapter. The I/O address of an adapter may be one of 0x1F0, 0x170, 0x330
or 0x230 and this is the order in which adapters will be found during au-
toconfiguration. Other addresses are not allowed. The IRQ of an adapter
may be one of 15, 14 or 12. The DRQ of an adapter may be one of 5, 6 or
7. The I/O address, IRQ and DRQ qualifiers in the system configuration
file are optional however if specified, only adapters which exactly match
the qualifiers will be found. Adapters with system configuration file
entries which do not specify a DRQ will be probed during autoconfigura-
tion without using DMA. A 16-bit ISA slot is required when specifying a
DRQ.
The DPT EISA and PCI adapters automatically configure using the configu-
ration mechanism of the bus they are on. For the EISA adapters the EISA
configuration utility must be run to set the IRQ and let the system BIOS
know that there is a card present. With PCI adapters the IRQ sometimes
has to be assigned from a BIOS configuration menu (some BIOS's do this
automatically).
Some configurations using multiple adapters require that an EISA adapter
at I/O port 0x1F0 be located and configured before the remaining
adapters. For special situations like this the "flags" configuration
field may be set to 1 to enable this behavior in the driver. The flags
field may be added to the kernel configuration file like this:
dpt0 at any? flags 1
Or it can be specified as a boot command in either the boot.default file
or on the boot command line:
-dev dpt0 flags=1
DPT adapters which support wide SCSI or multiple SCSI channels are a spe-
cial case and require some additions to the configuration file. These
adapters use the concept of a "pseudo host bus adapter" to work around
addressing limitations in the driver. In the wide SCSI case, all narrow
targets (target IDs < 8) appear as targets of the real adapter. However
all wide targets appear as targets of a pseudo-adapter which appears as
the next adapter described in the configuration file. For example, a
PM3224W is configured with one narrow SCSI disk drive as target 0 and one
wide SCSI disk drive as target 8. The config entry looks like this:
dpt0 at pci ?
dpt1 at pci ?
The narrow SCSI drive shows up as target 0 of adapter dpt0. The wide SC-
SI drive shows up as target 0 of dpt1. Note that dpt1 does not physically
exist. Enough entries in the system configuration file must be created
to satisfy ALL real and pseudo adapters which might be created during au-
toconfiguration. Adapters which support multiple SCSI buses behave simi-
larly. A separate pseudo-adapter is created for each additional SCSI bus.
Note that buses which have no targets either because no targets are con-
nected or because those targets are powered off will not be found during
autoconfiguration. In the case of adapters which support multiple SCSI
buses through the use of "pseudo" adapters, this can lead to an unexpect-
ed numbering of adapters which will undoubtedly cause grief. It is
strongly suggested, therefore, that all targets be connected and powered
up before autoconfiguration takes place.
All DPT host bus adapters must be configured before they can be used with
any operating system. Please contact DPT directly to obtain the latest
information on configuration utilities for DPT adapters. Note that in
the absence of a native BSD/OS version of the dptmgr configuration utili-
ty the DOS version may be used (under DOS) to configure DPT adapters
which will then later be used by BSD/OS. However please be aware that the
DOS version may allow the creation of configurations, like software
RAIDs, which are not supported by BSD/OS.
DIAGNOSTICS
The following diagnostics may be printed during autoconfiguration:
dpt0: probe failed - hardcoded IRQ doesn't match config data (irq 5)
An adapter specified in the system configuration file was found but the
IRQ reported by the adapter did not match the IRQ in the system configu-
ration file. Resolve the conflict between the jumpers on the adapter and
the value specified in the system configuration file.
dpt0: probe failed - hardcoded DRQ (drq 7) doesn't match config data
(drq 5)
An adapter specified in the system configuration file was found but the
DRQ reported by the adapter did not match the DRQ in the system configu-
ration file. Resolve the conflict between the jumpers on the adapter and
the value specified in the system configuration file.
SEE ALSOsd(4),
HISTORY
The dpt driver first appeared as a patch to BSD/OS 2.1.
BSDI BSD/OS June 6, 1996 2
