NAME

bt —

Buslogic/Mylex MultiMaster SCSI host adapter driver

SYNOPSIS

To compile this driver into the kernel, place the following lines in your kernel configuration file:

device isa
device scbus
device bt

In /boot/device.hints:
hint.bt.0.at="isa"
hint.bt.0.port="0x330"

DEPRECATION NOTICE

This driver is scheduled for removal prior to the release of FreeBSD 13.0.

DESCRIPTION

This driver provides access to the SCSI bus connected to a Buslogic/Mylex MultiMaster or compatible controller:

MultiMaster "W" Series Host Adapters:

Adapter	Bus	Commands	Description
BT-948	PCI	192	Ultra SCSI-3
BT-958	PCI	192	Wide Ultra SCSI-3
BT-958D	PCI	192	Wide Differential Ultra SCSI-3

MultiMaster "C" Series Host Adapters:

Adapter	Bus	Commands	Description
BT-946C	PCI	100	Fast SCSI-2
BT-956C	PCI	100	Wide Fast SCSI-2
BT-956CD	PCI	100	Wide Differential Fast SCSI-2
BT-445C	VLB	100	Fast SCSI-2
BT-545C	ISA	50	Fast SCSI-2
BT-540CF	ISA	50	Fast SCSI-2

MultiMaster "S" Series Host Adapters:

Adapter	Bus	Commands	Description
BT-445S	VLB	30	Fast SCSI-2
BT-545S	ISA	30	Fast SCSI-2
BT-542D	ISA	30	Differential Fast SCSI-2
BT-542B	ISA	30	SCSI-2 (542B revision H)

MultiMaster "A" Series Host Adapters:

Adapter	Bus	Commands	Description
BT-542B	ISA	30	SCSI-2 (542B revisions A - G)

Tagged queueing is supported on 'W' series adapters, 'C' series adapters with firmware of rev 4.42 and higher, and 'S' series adapters with firmware of rev 3.35 and higher.

Boards with certain firmware revisions may lock up under heavy load to certain devices, especially if tagged queueing is used. Should you encounter a problem with your adapter, contact Mylex technical support and ensure you have the latest firmware for your controller.

HARDWARE

The bt driver supports the following BusLogic MultiMaster “W”, “C”, “S”, and “A” series and compatible SCSI host adapters:

BusLogic BT-445C
BusLogic BT-445S
BusLogic BT-540CF
BusLogic BT-542B
BusLogic BT-542B
BusLogic BT-542D
BusLogic BT-545C
BusLogic BT-545S
BusLogic/BusTek BT-640
BusLogic BT-946C
BusLogic BT-948
BusLogic BT-956C
BusLogic BT-956CD
BusLogic BT-958
BusLogic BT-958D
Storage Dimensions SDC3211B / SDC3211F

HISTORY

The bt driver first appeared in the 386BSD patch kit.

AUTHORS

Julian Elischer wrote a driver for the Multimaster cards that appeared in the 386BSD patch kit. The driver was rewritten by Justin T. Gibbs to take advantage of new board features and work with the CAM SCSI framework in FreeBSD 3.0.

Special thanks to Leonard N. Zubkoff for writing such a complete and well documented Mylex/BusLogic MultiMaster driver for Linux. Support in this driver for the wide range of MultiMaster controllers and firmware revisions, with their otherwise undocumented quirks, would not have been possible without his efforts.