Lines Matching refs:SCSI
2 -=< The IBM Microchannel SCSI-Subsystem >=-
19 IBM MCA SCSI driver for Linux. Please note, that driver releases 4.0
29 - Chris Beauregard (improvement of the SCSI-device mapping by the driver)
31 - Klaus Kudielka (multiple SCSI-host management/detection, adaption to
42 2.1 IBM SCSI-Subsystem Detection
44 2.3 SCSI-Device Recognition and dynamical ldn Assignment
45 2.4 SCSI-Device Order
46 2.5 Regular SCSI-Command-Processing
54 2.13 Supported IBM SCSI-Subsystems
74 This README-file describes the IBM SCSI-subsystem low level driver for
85 2.1 IBM SCSI-Subsystem Detection
88 Microchannel-bus support is enabled, as the IBM SCSI-subsystem needs the
90 interrupt handler is connected to it to handle answers of the SCSI-
91 subsystem(s). If the F/W SCSI-adapter is forced by the BIOS to use IRQ11
92 instead of IRQ14, IRQ11 is used for the IBM SCSI-2 F/W adapter. In a
94 the kernel commandline, where the I/O port and the SCSI-subsystem id can
95 be specified. The next step checks if there is an integrated SCSI-subsystem
99 integrated SCSI-controller is available. But on certain PS/2s, like model
101 stage confused the driver and resulted in the detection of some ghost-SCSI.
103 registers are either 0xff or 0x00, there must be an integrated SCSI-
104 subsystem present and it will be registered as IBM Integrated SCSI-
108 adapter list, a SCSI-subsystem is assumed to be found in a slot and will be
110 more than one SCSI-adapter to be present in the PS/2-system and this is
115 I/O-address at 0x3540 - 0x3547, further installed IBM SCSI-adapters must
121 The POS2-register of all PS/2 models' integrated SCSI-subsystems has the
127 The POS3-register is interpreted as follows (for most IBM SCSI-subsys.):
128 Bit 7 - 5 : SCSI ID
130 The slot-adapters have different interpretation of these bits. The IBM SCSI
131 adapter (w/Cache) and the IBM SCSI-2 F/W adapter use the following
137 Bit 7 - 5 : SCSI ID
138 Bit 4 : Fairness Enable (SCSI ID3 f. F/W)
140 The most modern product of the series is the IBM SCSI-2 F/W adapter, it
141 allows dual-bus SCSI and SCSI-wide addressing, which means, PUNs may be
148 0x3540 for integrated SCSI-subsystems, there was a remark placed, that on
149 integrated IBM SCSI-subsystems of model 56, the POS2 register was showing 5.
156 Every time, a SCSI-subsystem is discovered, the ibmmca_register() function
158 address of this SCSI-subsystem is still available and assigns this I/O-
159 area to the SCSI-subsystem. There are always 8 sequential I/O-addresses
160 taken for each individual SCSI-subsystem found, which are:
174 driver itself and the mid- and higher-level SCSI-drivers. The SCSI pun/lun
181 There can be up to 56 devices on the SCSI bus (besides the adapter):
186 between 0 and 7). The IBM SCSI-2 F/W adapter offers this on up to two
199 The embedded microprocessor of the IBM SCSI-subsystem hides the complex
208 2.3 SCSI-Device Recognition and Dynamical ldn Assignment
214 the immediate assign command of the SCSI-subsystem for probing through
216 which is used by IBM SCSI-subsystems to access some valid SCSI-device.
225 These are presented to the upper layer of Linux SCSI driver
238 The physical SCSI-devices on the SCSI-bus are probed via immediate_assign-
241 SCSI-world that is now stored in the get_scsi[][]-array. This means,
246 there are more SCSI-devices installed than ldns available (n>15). The
249 SCSI-installations have optimum access-speed and are not touched by
252 there are less than 15 SCSI-devices connected. In the case of more than 15
256 dynamical reassignments on the SCSI-devices, until a certain device
258 during intense I/O between up to 15 SCSI-devices (means pun,lun
264 2.4 SCSI-Device Order
277 the assignment order of the SCSI-devices by flipping the PUN-assignment.
280 The problem for this is, that Linux does not assign the SCSI-devices in the
281 way as described in the ANSI-SCSI-standard. Linux assigns /dev/sda to
285 where the BIOS assigns drives belonging to the ANSI-SCSI-standard. Most
288 kernel enables to choose the preferred way of SCSI-device-assignment.
296 2.5 Regular SCSI-Command-Processing
314 to be even a problem with other SCSI-low level drivers, too. However,
337 This driver supports up to eight interfaces of type IBM-SCSI-Subsystem.
339 IBM-SCSI-Subsystem interfaces can be specified as kernel-parameters.
348 (software) or integrated (hardware) SCSI-command set (see below). The
353 used by the SCSI-subsystem. The load on each ldn is shown in the table,
356 15 pun/lun combinations available on the SCSI-bus.
366 address information of the SCSI-subsystem. This information is provided
369 2.13 Supported IBM SCSI-Subsystems
371 The following IBM SCSI-subsystems are supported by this driver:
373 - IBM Fast/Wide SCSI-2 Adapter
374 - IBM 7568 Industrial Computer SCSI Adapter w/Cache
375 - IBM Expansion Unit SCSI Controller
376 - IBM SCSI Adapter w/Cache
377 - IBM SCSI Adapter
378 - IBM Integrated SCSI Controller
380 system of IBM SCSI-adapters (forced detection)
384 The IBM SCSI-subsystem low level driver is prepared to be used with
403 A side effect is that the upper layer of Linux SCSI
435 for details. Did more fiddling with the integrated SCSI detection,
438 different integrated SCSI register configurations. However, the 56
449 Certain PS/2-models do not recognize a SCSI-subsystem automatically.
451 Thereafter, the routine probes for an integrated SCSI-subsystem.
453 possible combinations of multiple SCSI-subsystems on one MCA-board. Up to
454 eight SCSI-subsystems can be recognized and announced to the upper-level
460 1) SCSI-command capability enlarged by the recognition of MODE_SELECT.
463 necessary step to be allowed to set blocksize of SCSI-tape-drives and
464 the tape-speed, whithout confusing the SCSI-Subsystem.
502 seen by the driver. Everybody that has more than one IBM-SCSI should
504 than one IBM-SCSI hosts.
520 4) If one uses a SCSI-device of unsupported type/commands, one
522 understand which SCSI-command caused the problem, I extended this
527 1) Some cosmetical changes for the handling of SCSI-device-types.
528 Now, also CD-Burners / WORMs and SCSI-scanners should work. For
532 of a SCSI-device are stored.
533 2) There existed a small bug, that maps a device, coming after a SCSI-tape
537 vendor and revision-level of a SCSI-device for internal usage.
542 recognition and handling of SCSI-devices with the adapter. As I got
546 on the SCSI-subsystem. After that, it probes on all puns and luns for
550 by the assignment of all ldns to existing SCSI-devices. If more ldns
557 3) The LED-display shows on PS/2-95 no longer the ldn, but the SCSI-ID
558 (pun) of the accessed SCSI-device. This is now senseful, because the
563 physical and logical SCSI-devices are displayed. This could be very
564 interesting, when one is using more than 15 SCSI-devices in order to
577 IBM-SCSI-Subsystem-Adapter(s).
588 Therefore, we have a completely gapfree recognition of all SCSI-
591 the configuration, each connected SCSI-device will get a reset command
592 during boottime. This can be necessary for some special SCSI-devices.
627 2) Taking care of the SCSI-assignment problem, dealed by Chris at Dec 15
628 1997. In fact, IBM is right, concerning the assignment of SCSI-devices
629 to driveletters. It is conform to the ANSI-definition of the SCSI-
630 standard to assign drive C: to SCSI-id 6, because it is the highest
637 the IBM- and ANSI-SCSI-standard and keeps this driver downward
640 SCSI-BIOS do so. Therefore, I moved the IBMMCA_SCSI_ORDER_STANDARD
642 'IBM SCSI support'. A help, added to Documentation/Configure.help
650 some explanation about the SCSI-device-assignment problem.
666 2) The SCSI-subsystem detection was not complete and quite hugely buggy up
670 The pos-registers of integrated SCSI-subsystems do not contain any
684 not like sending commands to non-existing SCSI-devices and will react
686 present on IBM SCSI Adapter w/cache, it appears on IBM Integrated SCSI
690 how often the command errors have been forgiven to the SCSI-subsystem.
691 If the number is bigger than 0, you have a SCSI subsystem of older
696 pass the right name of the SCSI-adapter to Linux.
707 every integrated subsystem SCSI-command consequently in case of
712 on D. Weinehalls' Model 56, having integrated SCSI. This gave me the
740 It is obvious, that the IBM SCSI only delivers the tsb.dev_status, if
758 5) Taken into account ZP Gus' proposals to reverse the SCSI-device
766 various people, trying really quite different things on their SCSI-
770 - Driver panics while the midlevel-SCSI-driver is trying to inquire
771 the SCSI-device properties, even though hardware is in perfect state.
777 1024 bytes of space for the answer, but the IBM-SCSI-adapters do
778 not accept this, as they stick quite near to ANSI-SCSI and report
788 SCSI-subsystems report a command failure, if the returned buffersize
799 This increases SCSI-performance.
801 SCSI and 10 MHz on internal F/W SCSI-adapter.
811 2) Added the READ_CONTROL bit for test_unit_ready SCSI-command.
824 1) SCSI-2 F/W support crashed with a COMMAND ERROR. The reason for this
825 was, that it is possible to disbale Fast-SCSI for the external bus.
828 reports a COMMAND ERROR, if external bus Fast-SCSI is disabled. Now,
832 5 MHz (slow-) or 10 MHz (fast-SCSI). During feature probing, the
835 SCSI-devices, attached to the F/W-controller. If dual bus is selected,
836 only the internal SCSI-devices get accessed by Linux. For most
838 3) Wide-SCSI-addressing (16-Bit) is now possible for the internal F/W
843 4) Several machines use the SCSI: POS registers for internal/undocumented
845 models 9595, as it expected no onboard SCSI only, if all POS in
846 the integrated SCSI-area are set to 0x00 or 0xff. Now, the mechanism
847 to check for integrated SCSI is much more restrictive and these problems
857 normally get the inverse probing order of your devices on the SCSI-bus.
859 and tested algorithm inverts the device-order on the SCSI-bus and
860 automatically avoids accidental access to whatever SCSI PUN the adapter
861 is set and works with SCSI- and Wide-SCSI-addressing.
867 3) Auto-probing for maximum synchronous SCSI transfer rate is working.
869 5) Added some comment for the user to wait for SCSI-devices beeing probed.
919 6) All commands that get sent to the SCSI adapter were verified and
941 in internal SCSI-command handlers.
946 - IBM SCSI-2 F/W external SCSI bus support in seperate mode!
955 There exist several features for the IBM SCSI-subsystem driver.
968 where '-' stays dark, 'D' shows the SCSI-device id
969 and 'A' shows the SCSI hostindex, beeing currently
976 driver which can take up to two minutes per SCSI-adapter.
978 of the activities on the SCSI-bus. The display will have
984 when the SCSI-device is accessed. 'A' shows again the SCSI
991 wide-addressed devices e.g. at the SCSI-2 F/W adapter in
1002 alphanumeric LED display if you want to monitor SCSI-
1010 SCSI-subsystems' integrated SCSI-command set. Except of
1012 every IBM SCSI-subsystem to set its ldns right. Instead,
1013 the ordinary ANSI-SCSI-commands are used and passed by the
1014 controller to the SCSI-devices, therefore 'bypass'. The
1017 could maybe solve troubles with old or integrated SCSI-
1019 this flag will slow-down SCSI-accesses slightly, as the
1023 the Linux IBM-SCSI-driver, the bypass command should be
1025 SCSI-hardware!
1027 rail by ZP Gu. This parameter defines the SCSI-device
1029 the first SCSI-device is the one with the lowest pun.
1034 IBM, Microware and Microsoft, scans SCSI-devices starting
1037 like to have the same SCSI-device order, as in DOS, OS-9
1039 fast SCSI-I/O in synchronous mode is done at 5 MHz for IBM-
1040 SCSI-devices. SCSI-2 Fast/Wide Adapter/A external bus
1041 should then run at 10 MHz if Fast-SCSI is enabled,
1042 and at 5 MHz if Fast-SCSI is disabled on the external
1046 2.5 MHz for IBM SCSI-adapters and 5.0 MHz for F/W ext.
1047 SCSI-bus (when Fast-SCSI speed enabled on external bus).
1049 This means 1.82 MHz for IBM SCSI-adapters and 2.0 MHz
1050 for F/W external bus at Fast-SCSI speed on the external
1053 A further option is that you can force the SCSI-driver to accept a SCSI-
1060 e.g. ibmmcascsi=0x3540,7 will force the driver to detect a SCSI-subsystem
1062 the driver does really not recognize your SCSI-adapter! With driver version
1066 different types of IBM SCSI-adapters should be recognized correctly, too.
1079 and will force the driver to accept a SCSI-subsystem at I/O-base 0x3558
1087 Q: "Reset SCSI-devices at boottime" halts the system at boottime, why?
1088 A: This is only tested with the IBM SCSI Adapter w/cache. It is not
1092 kernel configuration, as all post 1989 SCSI-devices should accept
1093 the reset-signal, when the computer is switched on. The SCSI-
1096 SCSI-devices.
1097 Q: Why is the SCSI-order of my drives mirrored to the device-order
1100 ANSI-SCSI-standard (starting from pun 6 and going down to pun 0) or
1107 Q: Why I cannot find the IBM MCA SCSI support in the config menue?
1113 Q: My SCSI-adapter is not recognized by the driver, what can I do?
1119 Q: The driver screws up, if it starts to probe SCSI-devices, is there
1121 A: Yes, that was some recognition problem of the correct SCSI-adapter
1124 Q: I get a message: panic IBM MCA SCSI: command error .... , what can
1141 Q: Linux panics while dynamically assigning SCSI-ids or ldns.
1142 A: If you disconnect a SCSI-device from the machine, while Linux is up
1148 SCSI-adapter does really NOT generate any interrupt at the end of
1154 Q: The system gets in bad shape after a SCSI-reset, is this known?
1157 the reset functions with all other low level SCSI-drivers.
1164 some major overhead of SCSI-commands that risks the performance to
1166 Q: I have a IBM SCSI-2 Fast/Wide adapter, it boots in some way and hangs.
1167 A: Yes, that is understood, as for sure, your SCSI-2 Fast/Wide adapter
1168 was in such a case recognized as integrated SCSI-adapter or something
1171 should upgrade to the latest release of the SCSI-driver. The
1176 A: The reason for this is that the IBM SCSI-subsystem only sends a
1180 Q: I have a F/W adapter and the driver sees my internal SCSI-devices,
1183 no SCSI-id on the external devices appears on internal devices.
1186 SCSI-ids. If combined bus-mode is activated, on some adapters,
1189 Q: I have a 9595 and I get a NMI during heavy SCSI I/O e.g. during fsck.
1225 SCSI-drivers and won't have the time left to look inside every single
1237 When you get a SCSI-error message that panics your system, a list of
1238 register-entries of the SCSI-subsystem is shown (from Version 3.1d). With
1249 The address of the IBM SCSI-subsystem supporting WWW-page is:
1277 IBM Corp., "Personal System/2 Micro Channel SCSI
1280 IBM Corp., "Personal System/2 Micro Channel SCSI
1283 IBM Corp., "SCSI-2 Fast/Wide Adapter/A Technical Reference - Dual Bus",
1286 Friedhelm Schmidt, "SCSI-Bus und IDE-Schnittstelle - Moderne Peripherie-
1293 Andreas Kaiser, "SCSI TAPE BACKUP for OS/2 2.0", Version 2.12, Stuttgart
1305 SCSI-driver in order to get it running for some old machine
1308 who wrote the first release of the IBM SCSI-subsystem driver.
1310 who for a long time maintained MCA-Linux and the SCSI-driver
1315 it running with multiple SCSI-adapters.
1342 for support by shipping me an IBM SCSI-2 Fast/Wide manual.
1352 to thank him for his exhaustive SCSI-driver testing on his
1355 for his direct shipment of a SCSI F/W adapter, which allowed
1357 together with onboard SCSI adapter and some SCSI w/Cache.
1359 for his support by memory and an IBM SCSI-adapter. Collecting
1386 concerning the Linux-kernel in special, this SCSI-driver comes without any
1393 injuries by hardware defects, that could be caused by this SCSI-driver are