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diff --git a/kernel/Documentation/scsi/BusLogic.txt b/kernel/Documentation/scsi/BusLogic.txt new file mode 100644 index 000000000..48e982cd6 --- /dev/null +++ b/kernel/Documentation/scsi/BusLogic.txt @@ -0,0 +1,566 @@ + 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 + lnz@dandelion.com + + Copyright 1995-1998 by Leonard N. Zubkoff <lnz@dandelion.com> + + + 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 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://sourceforge.net/projects/dandelion/". + +Bug reports should be sent via electronic mail to "lnz@dandelion.com". 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 techsup@mylex.com, 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. + 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. + +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, + BusLogic has provided an AutoSCSI configuration option to enable a legacy ISA + compatible I/O port. + + To enable this backward compatibility option, invoke the AutoSCSI utility via + Ctrl-B at system startup and select "Adapter Configuration", "View/Modify + Configuration", and then change the "ISA Compatible Port" setting from + "Disable" to "Primary" or "Alternate". Once this driver has been installed, + the "ISA Compatible Port" option should be set back to "Disable" to avoid + possible future I/O port conflicts. The older BT-946C/956C/956CD also have + this configuration option, but the factory default setting is "Primary". + +o PCI Slot Scanning Order + + In systems with multiple BusLogic PCI Host Adapters, the order in which the + PCI slots are scanned may appear reversed with the BT-948/958/958D as + compared to the BT-946C/956C/956CD. For booting from a SCSI disk to work + correctly, it is necessary that the host adapter's BIOS and the kernel agree + on which disk is the boot device, which requires that they recognize the PCI + host adapters in the same order. The motherboard's PCI BIOS provides a + standard way of enumerating the PCI host adapters, which is used by the Linux + kernel. Some PCI BIOS implementations enumerate the PCI slots in order of + increasing bus number and device number, while others do so in the opposite + direction. + + Unfortunately, Microsoft decided that Windows 95 would always enumerate the + PCI slots in order of increasing bus number and device number regardless of + the PCI BIOS enumeration, and requires that their scheme be supported by the + host adapter's BIOS to receive Windows 95 certification. Therefore, the + factory default settings of the BT-948/958/958D enumerate the host adapters + by increasing bus number and device number. To disable this feature, invoke + the AutoSCSI utility via Ctrl-B at system startup and select "Adapter + Configuration", "View/Modify Configuration", press Ctrl-F10, and then change + the "Use Bus And Device # For PCI Scanning Seq." option to OFF. + + This driver will interrogate the setting of the PCI Scanning Sequence option + so as to recognize the host adapters in the same order as they are enumerated + by the host adapter's BIOS. + +o Enabling UltraSCSI Transfers + + The BT-948/958/958D 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. + + + DRIVER OPTIONS + +BusLogic Driver Options may be specified either via the Linux Kernel Command +Line or via the Loadable Kernel Module Installation Facility. Driver Options +for multiple host adapters may be specified either by separating the option +strings by a semicolon, or by specifying multiple "BusLogic=" strings on the +command line. Individual option specifications for a single host adapter are +separated by commas. The Probing and Debugging Options apply to all host +adapters whereas the remaining options apply individually only to the +selected host adapter. + +The BusLogic Driver Probing Options comprise the following: + +IO:<integer> + + The "IO:" option specifies an ISA I/O Address to be probed for a non-PCI + MultiMaster Host Adapter. If neither "IO:" nor "NoProbeISA" options are + specified, then the standard list of BusLogic MultiMaster ISA I/O Addresses + will be probed (0x330, 0x334, 0x230, 0x234, 0x130, and 0x134). Multiple + "IO:" options may be specified to precisely determine the I/O Addresses to + be probed, but the probe order will always follow the standard list. + +NoProbe + + The "NoProbe" option disables all probing and therefore no BusLogic Host + Adapters will be detected. + +NoProbeISA + + The "NoProbeISA" option disables probing of the standard BusLogic ISA I/O + Addresses and therefore only PCI MultiMaster and FlashPoint Host Adapters + will be detected. + +NoProbePCI + + The "NoProbePCI" options disables the interrogation of PCI Configuration + Space and therefore only ISA Multimaster Host Adapters will be detected, as + well as PCI Multimaster Host Adapters that have their ISA Compatible I/O + Port set to "Primary" or "Alternate". + +NoSortPCI + + The "NoSortPCI" option forces PCI MultiMaster Host Adapters to be + enumerated in the order provided by the PCI BIOS, ignoring any setting of + the AutoSCSI "Use Bus And Device # For PCI Scanning Seq." option. + +MultiMasterFirst + + The "MultiMasterFirst" option forces MultiMaster Host Adapters to be probed + before FlashPoint Host Adapters. By default, if both FlashPoint and PCI + MultiMaster Host Adapters are present, this driver will probe for + FlashPoint Host Adapters first unless the BIOS primary disk is controlled + by the first PCI MultiMaster Host Adapter, in which case MultiMaster Host + Adapters will be probed first. + +FlashPointFirst + + The "FlashPointFirst" option forces FlashPoint Host Adapters to be probed + before MultiMaster Host Adapters. + +The BusLogic Driver Tagged Queuing Options allow for explicitly specifying +the Queue Depth and whether Tagged Queuing is permitted for each Target +Device (assuming that the Target Device supports Tagged Queuing). The Queue +Depth is the number of SCSI Commands that are allowed to be concurrently +presented for execution (either to the Host Adapter or Target Device). Note +that explicitly enabling Tagged Queuing may lead to problems; the option to +enable or disable Tagged Queuing is provided primarily to allow disabling +Tagged Queuing on Target Devices that do not implement it correctly. The +following options are available: + +QueueDepth:<integer> + + The "QueueDepth:" or QD:" option specifies the Queue Depth to use for all + Target Devices that support Tagged Queuing, as well as the maximum Queue + Depth for devices that do not support Tagged Queuing. If no Queue Depth + option is provided, the Queue Depth will be determined automatically based + on the Host Adapter's Total Queue Depth and the number, type, speed, and + capabilities of the detected Target Devices. For Host Adapters that + require ISA Bounce Buffers, the Queue Depth is automatically set by default + to BusLogic_TaggedQueueDepthBB or BusLogic_UntaggedQueueDepthBB to avoid + excessive preallocation of DMA Bounce Buffer memory. Target Devices that + do not support Tagged Queuing always have their Queue Depth set to + BusLogic_UntaggedQueueDepth or BusLogic_UntaggedQueueDepthBB, unless a + lower Queue Depth option is provided. A Queue Depth of 1 automatically + disables Tagged Queuing. + +QueueDepth:[<integer>,<integer>...] + + The "QueueDepth:[...]" or "QD:[...]" option specifies the Queue Depth + individually for each Target Device. If an <integer> is omitted, the + associated Target Device will have its Queue Depth selected automatically. + +TaggedQueuing:Default + + The "TaggedQueuing:Default" or "TQ:Default" option permits Tagged Queuing + based on the firmware version of the BusLogic Host Adapter and based on + whether the Queue Depth allows queuing multiple commands. + +TaggedQueuing:Enable + + The "TaggedQueuing:Enable" or "TQ:Enable" option enables Tagged Queuing for + all Target Devices on this Host Adapter, overriding any limitation that + would otherwise be imposed based on the Host Adapter firmware version. + +TaggedQueuing:Disable + + The "TaggedQueuing:Disable" or "TQ:Disable" option disables Tagged Queuing + for all Target Devices on this Host Adapter. + +TaggedQueuing:<Target-Spec> + + The "TaggedQueuing:<Target-Spec>" or "TQ:<Target-Spec>" option controls + Tagged Queuing individually for each Target Device. <Target-Spec> is a + sequence of "Y", "N", and "X" characters. "Y" enables Tagged Queuing, "N" + disables Tagged Queuing, and "X" accepts the default based on the firmware + version. The first character refers to Target Device 0, the second to + Target Device 1, and so on; if the sequence of "Y", "N", and "X" characters + does not cover all the Target Devices, unspecified characters are assumed + to be "X". + +The BusLogic Driver Miscellaneous Options comprise the following: + +BusSettleTime:<seconds> + + The "BusSettleTime:" or "BST:" option specifies the Bus Settle Time in + seconds. The Bus Settle Time is the amount of time to wait between a Host + Adapter Hard Reset which initiates a SCSI Bus Reset and issuing any SCSI + Commands. If unspecified, it defaults to BusLogic_DefaultBusSettleTime. + +InhibitTargetInquiry + + The "InhibitTargetInquiry" option inhibits the execution of an Inquire + Target Devices or Inquire Installed Devices command on MultiMaster Host + Adapters. This may be necessary with some older Target Devices that do not + respond correctly when Logical Units above 0 are addressed. + +The BusLogic Driver Debugging Options comprise the following: + +TraceProbe + + The "TraceProbe" option enables tracing of Host Adapter Probing. + +TraceHardwareReset + + The "TraceHardwareReset" option enables tracing of Host Adapter Hardware + Reset. + +TraceConfiguration + + The "TraceConfiguration" option enables tracing of Host Adapter + Configuration. + +TraceErrors + + The "TraceErrors" option enables tracing of SCSI Commands that return an + error from the Target Device. The CDB and Sense Data will be printed for + each SCSI Command that fails. + +Debug + + The "Debug" option enables all debugging options. + +The following examples demonstrate setting the Queue Depth for Target Devices +1 and 2 on the first host adapter to 7 and 15, the Queue Depth for all Target +Devices on the second host adapter to 31, and the Bus Settle Time on the +second host adapter to 30 seconds. + +Linux Kernel Command Line: + + linux BusLogic=QueueDepth:[,7,15];QueueDepth:31,BusSettleTime:30 + +LILO Linux Boot Loader (in /etc/lilo.conf): + + append = "BusLogic=QueueDepth:[,7,15];QueueDepth:31,BusSettleTime:30" + +INSMOD Loadable Kernel Module Installation Facility: + + insmod BusLogic.o \ + 'BusLogic="QueueDepth:[,7,15];QueueDepth:31,BusSettleTime:30"' + +NOTE: Module Utilities 2.1.71 or later is required for correct parsing + of driver options containing commas. + + + DRIVER INSTALLATION + +This distribution was prepared for Linux kernel version 2.0.35, but should be +compatible with 2.0.4 or any later 2.0 series kernel. + +To install the new BusLogic SCSI driver, you may use the following commands, +replacing "/usr/src" with wherever you keep your Linux kernel source tree: + + cd /usr/src + tar -xvzf BusLogic-2.0.15.tar.gz + mv README.* LICENSE.* BusLogic.[ch] FlashPoint.c linux/drivers/scsi + patch -p0 < BusLogic.patch (only for 2.0.33 and below) + cd linux + make config + make zImage + +Then install "arch/x86/boot/zImage" as your standard kernel, run lilo if +appropriate, and reboot. + + + BUSLOGIC ANNOUNCEMENTS MAILING LIST + +The BusLogic Announcements Mailing List provides a forum for informing Linux +users of new driver releases and other announcements regarding Linux support +for BusLogic SCSI Host Adapters. To join the mailing list, send a message to +"buslogic-announce-request@dandelion.com" with the line "subscribe" in the +message body. |