readme.buslogic

linux和2410结合开发 用他可以生成2410所需的zImage文件

	   BusLogic MultiMaster and FlashPoint SCSI Driver for Linux

			 Version 2.0.15 for Linux 2.0
			 Version 2.1.15 for Linux 2.1

			      PRODUCTION RELEASE

				17 August 1998

			       Leonard N. Zubkoff
			       Dandelion Digital
			       [e-mail]

	 Copyright 1995-1998 by Leonard N. Zubkoff <[e-mail]>


				 INTRODUCTION

BusLogic, Inc. designed and manufactured a variety of high performance SCSI
host adapters which share a common programming interface across a diverse
collection of bus architectures by virtue of their MultiMaster ASIC technology.
BusLogic was acquired by Mylex Corporation in February 1996, but the products
supported by this driver originated under the BusLogic name and so that name is
retained in the source code and documentation.

This driver supports all present BusLogic MultiMaster Host Adapters, and should
support any future MultiMaster designs with little or no modification.  More
recently, BusLogic introduced the FlashPoint Host Adapters, which are less
costly and rely on the host CPU, rather than including an onboard processor.
Despite not having an onboard CPU, the FlashPoint Host Adapters perform very
well and have very low command latency.  BusLogic has recently provided me with
the FlashPoint Driver Developer's Kit, which comprises documentation and freely
redistributable source code for the FlashPoint SCCB Manager.  The SCCB Manager
is the library of code that runs on the host CPU and performs functions
analogous to the firmware on the MultiMaster Host Adapters.  Thanks to their
having provided the SCCB Manager, this driver now supports the FlashPoint Host
Adapters as well.

My primary goals in writing this completely new BusLogic driver for Linux are
to achieve the full performance that BusLogic SCSI Host Adapters and modern
SCSI peripherals are capable of, and to provide a highly robust driver that can
be depended upon for high performance mission critical applications.  All of
the major performance and error recovery features can be configured from the
Linux kernel command line or at module initialization time, allowing individual
installations to tune driver performance and error recovery to their particular
needs.

The latest information on Linux support for BusLogic SCSI Host Adapters, as
well as the most recent release of this driver and the latest firmware for the
BT-948/958/958D, will always be available from my Linux Home Page at URL
"http://www.dandelion.com/Linux/".

Bug reports should be sent via electronic mail to "[e-mail]".  Please
include with the bug report the complete configuration messages reported by the
driver and SCSI subsystem at startup, along with any subsequent system messages
relevant to SCSI operations, and a detailed description of your system's
hardware configuration.

Mylex has been an excellent company to work with and I highly recommend their
products to the Linux community.  In November 1995, I was offered the
opportunity to become a beta test site for their latest MultiMaster product,
the BT-948 PCI Ultra SCSI Host Adapter, and then again for the BT-958 PCI Wide
Ultra SCSI Host Adapter in January 1996.  This was mutually beneficial since
Mylex received a degree and kind of testing that their own testing group cannot
readily achieve, and the Linux community has available high performance host
adapters that have been well tested with Linux even before being brought to
market.  This relationship has also given me the opportunity to interact
directly with their technical staff, to understand more about the internal
workings of their products, and in turn to educate them about the needs and
potential of the Linux community.

More recently, Mylex has reaffirmed the company's interest in supporting the
Linux community, and I am now working on a Linux driver for the DAC960 PCI RAID
Controllers.  Mylex's interest and support is greatly appreciated.

Unlike some other vendors, if you contact Mylex Technical Support with a
problem and are running Linux, they will not tell you that your use of their
products is unsupported.  Their latest product marketing literature even states
"Mylex SCSI host adapters are compatible with all major operating systems
including: ... Linux ...".

Mylex Corporation is located at 34551 Ardenwood Blvd., Fremont, California
94555, USA and can be reached at 510/796-6100 or on the World Wide Web at
http://www.mylex.com.  Mylex HBA Technical Support can be reached by electronic
mail at [e-mail], by Voice at 510/608-2400, or by FAX at 510/745-7715.
Contact information for offices in Europe and Japan is available on the Web
site.


				DRIVER FEATURES

o Configuration Reporting and Testing

  During system initialization, the driver reports extensively on the host
  adapter hardware configuration, including the synchronous transfer parameters
  requested and negotiated with each target device.  AutoSCSI settings for
  Synchronous Negotiation, Wide Negotiation, and Disconnect/Reconnect are
  reported for each target device, as well as the status of Tagged Queuing and
  Error Recovery.  If the same setting is in effect for all target devices,
  then a single word or phrase is used; otherwise, a letter is provided for
  each target device to indicate the individual status.  The following examples
  should clarify this reporting format:

    Synchronous Negotiation: Ultra

      Synchronous negotiation is enabled for all target devices and the host
      adapter will attempt to negotiate for 20.0 mega-transfers/second.

    Synchronous Negotiation: Fast

      Synchronous negotiation is enabled for all target devices and the host
      adapter will attempt to negotiate for 10.0 mega-transfers/second.

    Synchronous Negotiation: Slow

      Synchronous negotiation is enabled for all target devices and the host
      adapter will attempt to negotiate for 5.0 mega-transfers/second.

    Synchronous Negotiation: Disabled

      Synchronous negotiation is disabled and all target devices are limited to
      asynchronous operation.

    Synchronous Negotiation: UFSNUUU#UUUUUUUU

      Synchronous negotiation to Ultra speed is enabled for target devices 0
      and 4 through 15, to Fast speed for target device 1, to Slow speed for
      target device 2, and is not permitted to target device 3.  The host
      adapter's SCSI ID is represented by the "#".

    The status of Wide Negotiation, Disconnect/Reconnect, and Tagged Queuing
    are reported as "Enabled", Disabled", or a sequence of "Y" and "N" letters.

    The Error Recovery option is reported as "Default", "Hard Reset",
    "Bus Device Reset", "None" or a sequence of "D", "H", "B", and "N" letters.

o Performance Features

  BusLogic SCSI Host Adapters directly implement SCSI-2 Tagged Queuing, and so
  support has been included in the driver to utilize tagged queuing with any
  target devices that report having the tagged queuing capability.  Tagged
  queuing allows for multiple outstanding commands to be issued to each target
  device or logical unit, and can improve I/O performance substantially.  In
  addition, BusLogic's Strict Round Robin Mode is used to optimize host adapter
  performance, and scatter/gather I/O can support as many segments as can be
  effectively utilized by the Linux I/O subsystem.  Control over the use of
  tagged queuing for each target device as well as individual selection of the
  tagged queue depth is available through driver options provided on the kernel
  command line or at module initialization time.  By default, the queue depth
  is determined automatically based on the host adapter's total queue depth and
  the number, type, speed, and capabilities of the target devices found.  In
  addition, tagged queuing is automatically disabled whenever the host adapter
  firmware version is known not to implement it correctly, or whenever a tagged
  queue depth of 1 is selected.  Tagged queuing is also disabled for individual
  target devices if disconnect/reconnect is disabled for that device.

o Robustness Features

  The driver implements extensive error recovery procedures.  When the higher
  level parts of the SCSI subsystem request that a timed out command be reset,
  a selection is made between a full host adapter hard reset and SCSI bus reset
  versus sending a bus device reset message to the individual target device
  based on the recommendation of the SCSI subsystem.  Error recovery strategies
  are selectable through driver options individually for each target device,
  and also include sending a bus device reset to the specific target device
  associated with the command being reset, as well as suppressing error
  recovery entirely to avoid perturbing an improperly functioning device.  If
  the bus device reset error recovery strategy is selected and sending a bus
  device reset does not restore correct operation, the next command that is
  reset will force a full host adapter hard reset and SCSI bus reset.  SCSI bus
  resets caused by other devices and detected by the host adapter are also
  handled by issuing a soft reset to the host adapter and re-initialization.
  Finally, if tagged queuing is active and more than one command reset occurs
  in a 10 minute interval, or if a command reset occurs within the first 10
  minutes of operation, then tagged queuing will be disabled for that target
  device.  These error recovery options improve overall system robustness by
  preventing individual errant devices from causing the system as a whole to
  lock up or crash, and thereby allowing a clean shutdown and restart after the
  offending component is removed.

o PCI Configuration Support

  On PCI systems running kernels compiled with PCI BIOS support enabled, this
  driver will interrogate the PCI configuration space and use the I/O port
  addresses assigned by the system BIOS, rather than the ISA compatible I/O
  port addresses.  The ISA compatible I/O port address is then disabled by the
  driver.  On PCI systems it is also recommended that the AutoSCSI utility be
  used to disable the ISA compatible I/O port entirely as it is not necessary.
  The ISA compatible I/O port is disabled by default on the BT-948/958/958D.

o /proc File System Support

  Copies of the host adapter configuration information together with updated
  data transfer and error recovery statistics are available through the
  /proc/scsi/BusLogic/<N> interface.

o Shared Interrupts Support

  On systems that support shared interrupts, any number of BusLogic Host
  Adapters may share the same interrupt request channel.


			    SUPPORTED HOST ADAPTERS

The following list comprises the supported BusLogic SCSI Host Adapters as of
the date of this document.  It is recommended that anyone purchasing a BusLogic
Host Adapter not in the following table contact the author beforehand to verify
that it is or will be supported.

FlashPoint Series PCI Host Adapters:

FlashPoint LT (BT-930)	Ultra SCSI-3
FlashPoint LT (BT-930R)	Ultra SCSI-3 with RAIDPlus
FlashPoint LT (BT-920)	Ultra SCSI-3 (BT-930 without BIOS)
FlashPoint DL (BT-932)	Dual Channel Ultra SCSI-3
FlashPoint DL (BT-932R)	Dual Channel Ultra SCSI-3 with RAIDPlus
FlashPoint LW (BT-950)	Wide Ultra SCSI-3
FlashPoint LW (BT-950R)	Wide Ultra SCSI-3 with RAIDPlus
FlashPoint DW (BT-952)	Dual Channel Wide Ultra SCSI-3
FlashPoint DW (BT-952R)	Dual Channel Wide Ultra SCSI-3 with RAIDPlus

MultiMaster "W" Series Host Adapters:

BT-948	    PCI		Ultra SCSI-3
BT-958	    PCI		Wide Ultra SCSI-3
BT-958D	    PCI		Wide Differential Ultra SCSI-3

MultiMaster "C" Series Host Adapters:

BT-946C	    PCI		Fast SCSI-2
BT-956C	    PCI		Wide Fast SCSI-2
BT-956CD    PCI		Wide Differential Fast SCSI-2
BT-445C	    VLB		Fast SCSI-2
BT-747C	    EISA	Fast SCSI-2
BT-757C	    EISA	Wide Fast SCSI-2
BT-757CD    EISA	Wide Differential Fast SCSI-2
BT-545C	    ISA		Fast SCSI-2
BT-540CF    ISA		Fast SCSI-2

MultiMaster "S" Series Host Adapters:

BT-445S	    VLB		Fast SCSI-2
BT-747S	    EISA	Fast SCSI-2
BT-747D	    EISA	Differential Fast SCSI-2
BT-757S	    EISA	Wide Fast SCSI-2
BT-757D	    EISA	Wide Differential Fast SCSI-2
BT-545S	    ISA		Fast SCSI-2
BT-542D	    ISA		Differential Fast SCSI-2
BT-742A	    EISA	SCSI-2 (742A revision H)
BT-542B	    ISA		SCSI-2 (542B revision H)

MultiMaster "A" Series Host Adapters:

BT-742A	    EISA	SCSI-2 (742A revisions A - G)
BT-542B	    ISA		SCSI-2 (542B revisions A - G)

AMI FastDisk Host Adapters that are true BusLogic MultiMaster clones are also
supported by this driver.

BusLogic SCSI Host Adapters are available packaged both as bare boards and as
retail kits.  The BT- model numbers above refer to the bare board packaging.
The retail kit model numbers are found by replacing BT- with KT- in the above
list.  The retail kit includes the bare board and manual as well as cabling and
driver media and documentation that are not provided with bare boards.


			 FLASHPOINT INSTALLATION NOTES

o RAIDPlus Support

  FlashPoint Host Adapters now include RAIDPlus, Mylex's bootable software
  RAID.  RAIDPlus is not supported on Linux, and there are no plans to support
  it.  The MD driver in Linux 2.0 provides for concatenation (LINEAR) and
  striping (RAID-0), and support for mirroring (RAID-1), fixed parity (RAID-4),
  and distributed parity (RAID-5) is available separately.  The built-in Linux
  RAID support is generally more flexible and is expected to perform better
  than RAIDPlus, so there is little impetus to include RAIDPlus support in the
  BusLogic driver.

o Enabling UltraSCSI Transfers

  FlashPoint Host Adapters ship with their configuration set to "Factory
  Default" settings that are conservative and do not allow for UltraSCSI speed
  to be negotiated.  This results in fewer problems when these host adapters
  are installed in systems with cabling or termination that is not sufficient
  for UltraSCSI operation, or where existing SCSI devices do not properly
  respond to synchronous transfer negotiation for UltraSCSI speed.  AutoSCSI
  may be used to load "Optimum Performance" settings which allow UltraSCSI
  speed to be negotiated with all devices, or UltraSCSI speed can be enabled on
  an individual basis.  It is recommended that SCAM be manually disabled after
  the "Optimum Performance" settings are loaded.


		      BT-948/958/958D INSTALLATION NOTES

The BT-948/958/958D PCI Ultra SCSI Host Adapters have some features which may
require attention in some circumstances when installing Linux.

o PCI I/O Port Assignments

  When configured to factory default settings, the BT-948/958/958D will only
  recognize the PCI I/O port assignments made by the motherboard's PCI BIOS.
  The BT-948/958/958D will not respond to any of the ISA compatible I/O ports
  that previous BusLogic SCSI Host Adapters respond to.  This driver supports
  the PCI I/O port assignments, so this is the preferred configuration.
  However, if the obsolete BusLogic driver must be used for any reason, such as
  a Linux distribution that does not yet use this driver in its boot kernel,