NAME

dpt - DPT 2011, 2021, 2012 and 2022 low-level controller modules

AVAILABILITY

x86

DESCRIPTION

The dpt module provides low-level interface routines between the common disk/tape I/O subsystem and the DPT ISA bus master 2011 and 2021 SCSI (Small Computer System Interface) and DPT EISA 2012 and 2022 SCSI controllers. The dpt module can be configured for disk and streaming tape support for one or more host adapter boards, each of which must be the sole initiator on a SCSI bus. Auto configuration code determines if the adapter is present at the configured address and what types of devices are attached to it. If a memory cache module is installed on the DPT board, this cache will be flushed to disk by the dpt driver module when the system is shut down by the system administrator.

Board Configuration and Auto

In order to boot from a 2011, 2021, 2012, or 2022 host adapter, it must first be configured correctly.

Configuration

DPT 2011 and DPT 2021 ISA SCSI Bus

The DPT 2011 and DPT 2021 are adapters that are configured using jumpers. Before installation of an operating system, the utility dptfmt must be run to prepare disk drives for use by the adapter. You will be required to enter emulation information as part of this procedure. There is information for two drives, and it should show ``disabled'' for both. Failure to perform this step will result in missing drives during the system boot process. The entry for drive types should be set to 0 for drives zero and one. This indicates ``no drives present'' and disables the emulation mode of the adapter, thus allowing correct operation of the native mode driver. The user configurable parameters in the /kernel/drv/dpt.conf file for the DPT 2011 and DPT 2021 are:

Master Host Bus Adapters

io port "reg=0x1f0,0,0" "ioaddr=0x1f0"
priority level (5) and IRQ (interrupt) 14 "intr=5,15"

The I/O port (ioaddr )is the ISA bus base I/O address used for communication with the adapter. The same base address should appear after reg=XXX and ioaddr=XXX. The first DPT 2011 or DPT 2021 should be set to 0x1f0, and the next to 0x170. Each 2011 or 2021 should have a unique direct memory access (DMA) channel. The first 2011 or 2021 should be on DMA channel 5. The dpt module reads the 2011 or 2021 DMA channel at auto configuration time, so no parameter is necessary in the configuration file. The interrupt priority level should always be 5. The boot adapter should be set to IRQ (interrupt) 15. Each 2011 or 2021 should have a unique I/O port and a unique DMA channel. Use of a different interrupt level for each board is required.

A complete entry in /kernel/drv/dpt.conf is:

name="dpt" class="sysbus" intr=5,14 reg=0x1f0,0,0
        ioaddr=0x1f0
        flow_control="dmult" queue="qsort" disk="scdk" tape="sctp" ;

DPT 2012 AND DPT 2022 EISA SCSI Host

These are adapters that are configured using the EISA configuration utility supplied by the computer manufacturer in conjunction with a configuration file. You will be required to enter emulation information as part of the configuration process. There is information for two drives, and it should show ``disabled'' for both. When asked for drive types for drives zero and one, enter 0. This indicates ``no drives present'' and disables the WD1003 emulation mode of the adapter, allowing correct operation of the native mode driver. You will also be required to use a DPT format utility to configure hard drives prior to installation. The only relevant user configurable item in dpt.conf is:

Bus Adapters

io address "reg=0x1c88,0,0"
        "ioaddr=0x1c88"

The I/O address is 0x1000 times the EISA slot number + 0xc88. Hence, slot 1 is address 0x1c88 and slot 10 is 0xac88. The same base address should appear after reg=XXX and ioaddr=XXX.

The first default EISA listing from the configuration file is:

#       eisa-type hba
name="dpt" class="sysbus" intr=5,14 reg=0x1c88,0,0
        ioaddr=0x1c88
        flow_control="dmult" queue="qsort" disk="scdk" tape="sctp" ;

To speed boot, parameters in the configuration file may be commented out with a "#" in the first column for controllers that are not installed.