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Linus Torvalds1da177e2005-04-16 15:20:36 -07001The Linux NCR53C8XX/SYM53C8XX drivers README file
2
3Written by Gerard Roudier <groudier@free.fr>
421 Rue Carnot
595170 DEUIL LA BARRE - FRANCE
6
729 May 1999
8===============================================================================
9
101. Introduction
112. Supported chips and SCSI features
123. Advantages of the enhanced 896 driver
13 3.1 Optimized SCSI SCRIPTS
14 3.2 New features of the SYM53C896 (64 bit PCI dual LVD SCSI controller)
154. Memory mapped I/O versus normal I/O
165. Tagged command queueing
176. Parity checking
187. Profiling information
198. Control commands
20 8.1 Set minimum synchronous period
21 8.2 Set wide size
22 8.3 Set maximum number of concurrent tagged commands
23 8.4 Set order type for tagged command
24 8.5 Set debug mode
25 8.6 Clear profile counters
26 8.7 Set flag (no_disc)
27 8.8 Set verbose level
28 8.9 Reset all logical units of a target
29 8.10 Abort all tasks of all logical units of a target
309. Configuration parameters
3110. Boot setup commands
32 10.1 Syntax
33 10.2 Available arguments
34 10.2.1 Master parity checking
35 10.2.2 Scsi parity checking
36 10.2.3 Scsi disconnections
37 10.2.4 Special features
38 10.2.5 Ultra SCSI support
39 10.2.6 Default number of tagged commands
40 10.2.7 Default synchronous period factor
41 10.2.8 Negotiate synchronous with all devices
42 10.2.9 Verbosity level
43 10.2.10 Debug mode
44 10.2.11 Burst max
45 10.2.12 LED support
46 10.2.13 Max wide
47 10.2.14 Differential mode
48 10.2.15 IRQ mode
49 10.2.16 Reverse probe
50 10.2.17 Fix up PCI configuration space
51 10.2.18 Serial NVRAM
52 10.2.19 Check SCSI BUS
53 10.2.20 Exclude a host from being attached
54 10.2.21 Suggest a default SCSI id for hosts
55 10.2.22 Enable use of IMMEDIATE ARBITRATION
56 10.3 Advised boot setup commands
57 10.4 PCI configuration fix-up boot option
58 10.5 Serial NVRAM support boot option
59 10.6 SCSI BUS checking boot option
60 10.7 IMMEDIATE ARBITRATION boot option
6111. Some constants and flags of the ncr53c8xx.h header file
6212. Installation
6313. Architecture dependent features
6414. Known problems
65 14.1 Tagged commands with Iomega Jaz device
66 14.2 Device names change when another controller is added
67 14.3 Using only 8 bit devices with a WIDE SCSI controller.
68 14.4 Possible data corruption during a Memory Write and Invalidate
69 14.5 IRQ sharing problems
7015. SCSI problem troubleshooting
71 15.1 Problem tracking
72 15.2 Understanding hardware error reports
7316. Synchonous transfer negotiation tables
74 16.1 Synchronous timings for 53C875 and 53C860 Ultra-SCSI controllers
75 16.2 Synchronous timings for fast SCSI-2 53C8XX controllers
7617. Serial NVRAM support (by Richard Waltham)
77 17.1 Features
78 17.2 Symbios NVRAM layout
79 17.3 Tekram NVRAM layout
8018. Support for Big Endian
81 18.1 Big Endian CPU
82 18.2 NCR chip in Big Endian mode of operations
83
84===============================================================================
85
861. Introduction
87
88The initial Linux ncr53c8xx driver has been a port of the ncr driver from
89FreeBSD that has been achieved in November 1995 by:
90 Gerard Roudier <groudier@free.fr>
91
92The original driver has been written for 386bsd and FreeBSD by:
93 Wolfgang Stanglmeier <wolf@cologne.de>
94 Stefan Esser <se@mi.Uni-Koeln.de>
95
96It is now available as a bundle of 2 drivers:
97
98- ncr53c8xx generic driver that supports all the SYM53C8XX family including
99 the ealiest 810 rev. 1, the latest 896 (2 channel LVD SCSI controller) and
100 the new 895A (1 channel LVD SCSI controller).
101- sym53c8xx enhanced driver (a.k.a. 896 drivers) that drops support of oldest
102 chips in order to gain advantage of new features, as LOAD/STORE intructions
103 available since the 810A and hardware phase mismatch available with the
104 896 and the 895A.
105
106You can find technical information about the NCR 8xx family in the
107PCI-HOWTO written by Michael Will and in the SCSI-HOWTO written by
108Drew Eckhardt.
109
110Information about new chips is available at LSILOGIC web server:
111
112 http://www.lsilogic.com/
113
114SCSI standard documentations are available at SYMBIOS ftp server:
115
116 ftp://ftp.symbios.com/
117
118Usefull SCSI tools written by Eric Youngdale are available at tsx-11:
119
120 ftp://tsx-11.mit.edu/pub/linux/ALPHA/scsi/scsiinfo-X.Y.tar.gz
121 ftp://tsx-11.mit.edu/pub/linux/ALPHA/scsi/scsidev-X.Y.tar.gz
122
123These tools are not ALPHA but quite clean and work quite well.
124It is essential you have the 'scsiinfo' package.
125
126This short documentation describes the features of the generic and enhanced
127drivers, configuration parameters and control commands available through
128the proc SCSI file system read / write operations.
129
130This driver has been tested OK with linux/i386, Linux/Alpha and Linux/PPC.
131
132Latest driver version and patches are available at:
133
134 ftp://ftp.tux.org/pub/people/gerard-roudier
135or
136 ftp://ftp.symbios.com/mirror/ftp.tux.org/pub/tux/roudier/drivers
137
138I am not a native speaker of English and there are probably lots of
139mistakes in this README file. Any help will be welcome.
140
141
1422. Supported chips and SCSI features
143
144The following features are supported for all chips:
145
146 Synchronous negotiation
147 Disconnection
148 Tagged command queuing
149 SCSI parity checking
150 Master parity checking
151
152"Wide negotiation" is supported for chips that allow it. The
153following table shows some characteristics of NCR 8xx family chips
154and what drivers support them.
155
156 Supported by Supported by
157 On board the generic the enhanced
158Chip SDMS BIOS Wide SCSI std. Max. sync driver driver
159---- --------- ---- --------- ---------- ------------ -------------
160810 N N FAST10 10 MB/s Y N
161810A N N FAST10 10 MB/s Y Y
162815 Y N FAST10 10 MB/s Y N
163825 Y Y FAST10 20 MB/s Y N
164825A Y Y FAST10 20 MB/s Y Y
165860 N N FAST20 20 MB/s Y Y
166875 Y Y FAST20 40 MB/s Y Y
167876 Y Y FAST20 40 MB/s Y Y
168895 Y Y FAST40 80 MB/s Y Y
169895A Y Y FAST40 80 MB/s Y Y
170896 Y Y FAST40 80 MB/s Y Y
171897 Y Y FAST40 80 MB/s Y Y
1721510D Y Y FAST40 80 MB/s Y Y
1731010 Y Y FAST80 160 MB/s N Y
1741010_66* Y Y FAST80 160 MB/s N Y
175
176* Chip supports 33MHz and 66MHz PCI buses.
177
178
179Summary of other supported features:
180
181Module: allow to load the driver
182Memory mapped I/O: increases performance
183Profiling information: read operations from the proc SCSI file system
184Control commands: write operations to the proc SCSI file system
185Debugging information: written to syslog (expert only)
186Scatter / gather
187Shared interrupt
188Boot setup commands
189Serial NVRAM: Symbios and Tekram formats
190
191
1923. Advantages of the enhanced 896 driver
193
1943.1 Optimized SCSI SCRIPTS.
195
196The 810A, 825A, 875, 895, 896 and 895A support new SCSI SCRIPTS instructions
197named LOAD and STORE that allow to move up to 1 DWORD from/to an IO register
198to/from memory much faster that the MOVE MEMORY instruction that is supported
199by the 53c7xx and 53c8xx family.
200The LOAD/STORE instructions support absolute and DSA relative addressing
201modes. The SCSI SCRIPTS had been entirely rewritten using LOAD/STORE instead
202of MOVE MEMORY instructions.
203
2043.2 New features of the SYM53C896 (64 bit PCI dual LVD SCSI controller)
205
206The 896 and the 895A allows handling of the phase mismatch context from
207SCRIPTS (avoids the phase mismatch interrupt that stops the SCSI processor
208until the C code has saved the context of the transfer).
209Implementing this without using LOAD/STORE instructions would be painfull
210and I did'nt even want to try it.
211
212The 896 chip supports 64 bit PCI transactions and addressing, while the
213895A supports 32 bit PCI transactions and 64 bit addressing.
214The SCRIPTS processor of these chips is not true 64 bit, but uses segment
215registers for bit 32-63. Another interesting feature is that LOAD/STORE
216instructions that address the on-chip RAM (8k) remain internal to the chip.
217
218Due to the use of LOAD/STORE SCRIPTS instructions, this driver does not
219support the following chips:
220- SYM53C810 revision < 0x10 (16)
221- SYM53C815 all revisions
222- SYM53C825 revision < 0x10 (16)
223
2244. Memory mapped I/O versus normal I/O
225
226Memory mapped I/O has less latency than normal I/O. Since
227linux-1.3.x, memory mapped I/O is used rather than normal I/O. Memory
228mapped I/O seems to work fine on most hardware configurations, but
229some poorly designed motherboards may break this feature.
230
231The configuration option CONFIG_SCSI_NCR53C8XX_IOMAPPED forces the
232driver to use normal I/O in all cases.
233
234
2355. Tagged command queueing
236
237Queuing more than 1 command at a time to a device allows it to perform
238optimizations based on actual head positions and its mechanical
239characteristics. This feature may also reduce average command latency.
240In order to really gain advantage of this feature, devices must have
241a reasonable cache size (No miracle is to be expected for a low-end
242hard disk with 128 KB or less).
243Some kown SCSI devices do not properly support tagged command queuing.
244Generally, firmware revisions that fix this kind of problems are available
245at respective vendor web/ftp sites.
246All I can say is that the hard disks I use on my machines behave well with
247this driver with tagged command queuing enabled:
248
249- IBM S12 0662
250- Conner 1080S
251- Quantum Atlas I
252- Quantum Atlas II
253
254If your controller has NVRAM, you can configure this feature per target
255from the user setup tool. The Tekram Setup program allows to tune the
256maximum number of queued commands up to 32. The Symbios Setup only allows
257to enable or disable this feature.
258
259The maximum number of simultaneous tagged commands queued to a device
260is currently set to 8 by default. This value is suitable for most SCSI
261disks. With large SCSI disks (>= 2GB, cache >= 512KB, average seek time
262<= 10 ms), using a larger value may give better performances.
263
264The sym53c8xx driver supports up to 255 commands per device, and the
265generic ncr53c8xx driver supports up to 64, but using more than 32 is
266generally not worth-while, unless you are using a very large disk or disk
267array. It is noticeable that most of recent hard disks seem not to accept
268more than 64 simultaneous commands. So, using more than 64 queued commands
269is probably just resource wasting.
270
271If your controller does not have NVRAM or if it is managed by the SDMS
272BIOS/SETUP, you can configure tagged queueing feature and device queue
273depths from the boot command-line. For example:
274
275 ncr53c8xx=tags:4/t2t3q15-t4q7/t1u0q32
276
277will set tagged commands queue depths as follow:
278
279- target 2 all luns on controller 0 --> 15
280- target 3 all luns on controller 0 --> 15
281- target 4 all luns on controller 0 --> 7
282- target 1 lun 0 on controller 1 --> 32
283- all other target/lun --> 4
284
285In some special conditions, some SCSI disk firmwares may return a
286QUEUE FULL status for a SCSI command. This behaviour is managed by the
287driver using the following heuristic:
288
289- Each time a QUEUE FULL status is returned, tagged queue depth is reduced
290 to the actual number of disconnected commands.
291
292- Every 1000 successfully completed SCSI commands, if allowed by the
293 current limit, the maximum number of queueable commands is incremented.
294
295Since QUEUE FULL status reception and handling is resource wasting, the
296driver notifies by default this problem to user by indicating the actual
297number of commands used and their status, as well as its decision on the
298device queue depth change.
299The heuristic used by the driver in handling QUEUE FULL ensures that the
300impact on performances is not too bad. You can get rid of the messages by
301setting verbose level to zero, as follow:
302
3031st method: boot your system using 'ncr53c8xx=verb:0' option.
3042nd method: apply "setverbose 0" control command to the proc fs entry
305 corresponding to your controller after boot-up.
306
3076. Parity checking
308
309The driver supports SCSI parity checking and PCI bus master parity
310checking. These features must be enabled in order to ensure safe data
311transfers. However, some flawed devices or mother boards will have
312problems with parity. You can disable either PCI parity or SCSI parity
313checking by entering appropriate options from the boot command line.
314(See 10: Boot setup commands).
315
3167. Profiling information
317
318Profiling information is available through the proc SCSI file system.
319Since gathering profiling information may impact performances, this
320feature is disabled by default and requires a compilation configuration
321option to be set to Y.
322
323The device associated with a host has the following pathname:
324
325 /proc/scsi/ncr53c8xx/N (N=0,1,2 ....)
326
327Generally, only 1 board is used on hardware configuration, and that device is:
328 /proc/scsi/ncr53c8xx/0
329
330However, if the driver has been made as module, the number of the
331hosts is incremented each time the driver is loaded.
332
333In order to display profiling information, just enter:
334
335 cat /proc/scsi/ncr53c8xx/0
336
337and you will get something like the following text:
338
339-------------------------------------------------------
340General information:
341 Chip NCR53C810, device id 0x1, revision id 0x2
342 IO port address 0x6000, IRQ number 10
343 Using memory mapped IO at virtual address 0x282c000
344 Synchronous transfer period 25, max commands per lun 4
345Profiling information:
346 num_trans = 18014
347 num_kbytes = 671314
348 num_disc = 25763
349 num_break = 1673
350 num_int = 1685
351 num_fly = 18038
352 ms_setup = 4940
353 ms_data = 369940
354 ms_disc = 183090
355 ms_post = 1320
356-------------------------------------------------------
357
358General information is easy to understand. The device ID and the
359revision ID identify the SCSI chip as follows:
360
361Chip Device id Revision Id
362---- --------- -----------
363810 0x1 < 0x10
364810A 0x1 >= 0x10
365815 0x4
366825 0x3 < 0x10
367860 0x6
368825A 0x3 >= 0x10
369875 0xf
370895 0xc
371
372The profiling information is updated upon completion of SCSI commands.
373A data structure is allocated and zeroed when the host adapter is
374attached. So, if the driver is a module, the profile counters are
375cleared each time the driver is loaded. The "clearprof" command
376allows you to clear these counters at any time.
377
378The following counters are available:
379
380("num" prefix means "number of",
381"ms" means milli-seconds)
382
383num_trans
384 Number of completed commands
385 Example above: 18014 completed commands
386
387num_kbytes
388 Number of kbytes transferred
389 Example above: 671 MB transferred
390
391num_disc
392 Number of SCSI disconnections
393 Example above: 25763 SCSI disconnections
394
395num_break
396 number of script interruptions (phase mismatch)
397 Example above: 1673 script interruptions
398
399num_int
400 Number of interrupts other than "on the fly"
401 Example above: 1685 interruptions not "on the fly"
402
403num_fly
404 Number of interrupts "on the fly"
405 Example above: 18038 interruptions "on the fly"
406
407ms_setup
408 Elapsed time for SCSI commands setups
409 Example above: 4.94 seconds
410
411ms_data
412 Elapsed time for data transfers
413 Example above: 369.94 seconds spent for data transfer
414
415ms_disc
416 Elapsed time for SCSI disconnections
417 Example above: 183.09 seconds spent disconnected
418
419ms_post
420 Elapsed time for command post processing
421 (time from SCSI status get to command completion call)
422 Example above: 1.32 seconds spent for post processing
423
424Due to the 1/100 second tick of the system clock, "ms_post" time may
425be wrong.
426
427In the example above, we got 18038 interrupts "on the fly" and only
4281673 script breaks generally due to disconnections inside a segment
429of the scatter list.
430
431
4328. Control commands
433
434Control commands can be sent to the driver with write operations to
435the proc SCSI file system. The generic command syntax is the
436following:
437
438 echo "<verb> <parameters>" >/proc/scsi/ncr53c8xx/0
439 (assumes controller number is 0)
440
441Using "all" for "<target>" parameter with the commands below will
442apply to all targets of the SCSI chain (except the controller).
443
444Available commands:
445
4468.1 Set minimum synchronous period factor
447
448 setsync <target> <period factor>
449
450 target: target number
451 period: minimum synchronous period.
452 Maximum speed = 1000/(4*period factor) except for special
453 cases below.
454
455 Specify a period of 255, to force asynchronous transfer mode.
456
457 10 means 25 nano-seconds synchronous period
458 11 means 30 nano-seconds synchronous period
459 12 means 50 nano-seconds synchronous period
460
4618.2 Set wide size
462
463 setwide <target> <size>
464
465 target: target number
466 size: 0=8 bits, 1=16bits
467
4688.3 Set maximum number of concurrent tagged commands
469
470 settags <target> <tags>
471
472 target: target number
473 tags: number of concurrent tagged commands
474 must not be greater than SCSI_NCR_MAX_TAGS (default: 8)
475
4768.4 Set order type for tagged command
477
478 setorder <order>
479
480 order: 3 possible values:
481 simple: use SIMPLE TAG for all operations (read and write)
482 ordered: use ORDERED TAG for all operations
483 default: use default tag type,
484 SIMPLE TAG for read operations
485 ORDERED TAG for write operations
486
487
4888.5 Set debug mode
489
490 setdebug <list of debug flags>
491
492 Available debug flags:
493 alloc: print info about memory allocations (ccb, lcb)
494 queue: print info about insertions into the command start queue
495 result: print sense data on CHECK CONDITION status
496 scatter: print info about the scatter process
497 scripts: print info about the script binding process
498 tiny: print minimal debugging information
499 timing: print timing information of the NCR chip
500 nego: print information about SCSI negotiations
501 phase: print information on script interruptions
502
503 Use "setdebug" with no argument to reset debug flags.
504
505
5068.6 Clear profile counters
507
508 clearprof
509
510 The profile counters are automatically cleared when the amount of
511 data transferred reaches 1000 GB in order to avoid overflow.
512 The "clearprof" command allows you to clear these counters at any time.
513
514
5158.7 Set flag (no_disc)
516
517 setflag <target> <flag>
518
519 target: target number
520
521 For the moment, only one flag is available:
522
523 no_disc: not allow target to disconnect.
524
525 Do not specify any flag in order to reset the flag. For example:
526 - setflag 4
527 will reset no_disc flag for target 4, so will allow it disconnections.
528 - setflag all
529 will allow disconnection for all devices on the SCSI bus.
530
531
5328.8 Set verbose level
533
534 setverbose #level
535
536 The driver default verbose level is 1. This command allows to change
537 th driver verbose level after boot-up.
538
5398.9 Reset all logical units of a target
540
541 resetdev <target>
542
543 target: target number
544 The driver will try to send a BUS DEVICE RESET message to the target.
545 (Only supported by the SYM53C8XX driver and provided for test purpose)
546
5478.10 Abort all tasks of all logical units of a target
548
549 cleardev <target>
550
551 target: target number
552 The driver will try to send a ABORT message to all the logical units
553 of the target.
554 (Only supported by the SYM53C8XX driver and provided for test purpose)
555
556
5579. Configuration parameters
558
559If the firmware of all your devices is perfect enough, all the
560features supported by the driver can be enabled at start-up. However,
561if only one has a flaw for some SCSI feature, you can disable the
562support by the driver of this feature at linux start-up and enable
563this feature after boot-up only for devices that support it safely.
564
565CONFIG_SCSI_NCR53C8XX_PROFILE_SUPPORT (default answer: n)
566 This option must be set for profiling information to be gathered
567 and printed out through the proc file system. This features may
568 impact performances.
569
570CONFIG_SCSI_NCR53C8XX_IOMAPPED (default answer: n)
571 Answer "y" if you suspect your mother board to not allow memory mapped I/O.
572 May slow down performance a little. This option is required by
573 Linux/PPC and is used no matter what you select here. Linux/PPC
574 suffers no performance loss with this option since all IO is memory
575 mapped anyway.
576
577CONFIG_SCSI_NCR53C8XX_DEFAULT_TAGS (default answer: 8)
578 Default tagged command queue depth.
579
580CONFIG_SCSI_NCR53C8XX_MAX_TAGS (default answer: 8)
581 This option allows you to specify the maximum number of tagged commands
582 that can be queued to a device. The maximum supported value is 32.
583
584CONFIG_SCSI_NCR53C8XX_SYNC (default answer: 5)
585 This option allows you to specify the frequency in MHz the driver
586 will use at boot time for synchronous data transfer negotiations.
587 This frequency can be changed later with the "setsync" control command.
588 0 means "asynchronous data transfers".
589
590CONFIG_SCSI_NCR53C8XX_FORCE_SYNC_NEGO (default answer: n)
591 Force synchronous negotiation for all SCSI-2 devices.
592 Some SCSI-2 devices do not report this feature in byte 7 of inquiry
593 response but do support it properly (TAMARACK scanners for example).
594
595CONFIG_SCSI_NCR53C8XX_NO_DISCONNECT (default and only reasonable answer: n)
596 If you suspect a device of yours does not properly support disconnections,
597 you can answer "y". Then, all SCSI devices will never disconnect the bus
598 even while performing long SCSI operations.
599
600CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT
601 Genuine SYMBIOS boards use GPIO0 in output for controller LED and GPIO3
602 bit as a flag indicating singled-ended/differential interface.
603 If all the boards of your system are genuine SYMBIOS boards or use
604 BIOS and drivers from SYMBIOS, you would want to enable this option.
605 This option must NOT be enabled if your system has at least one 53C8XX
606 based scsi board with a vendor-specific BIOS.
607 For example, Tekram DC-390/U, DC-390/W and DC-390/F scsi controllers
608 use a vendor-specific BIOS and are known to not use SYMBIOS compatible
609 GPIO wiring. So, this option must not be enabled if your system has
610 such a board installed.
611
612CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT
613 Enable support for reading the serial NVRAM data on Symbios and
614 some Symbios compatible cards, and Tekram DC390W/U/F cards. Useful for
615 systems with more than one Symbios compatible controller where at least
616 one has a serial NVRAM, or for a system with a mixture of Symbios and
617 Tekram cards. Enables setting the boot order of host adaptors
618 to something other than the default order or "reverse probe" order.
619 Also enables Symbios and Tekram cards to be distinguished so
620 CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT may be set in a system with a
621 mixture of Symbios and Tekram cards so the Symbios cards can make use of
622 the full range of Symbios features, differential, led pin, without
623 causing problems for the Tekram card(s).
624
62510. Boot setup commands
626
62710.1 Syntax
628
629Setup commands can be passed to the driver either at boot time or as a
630string variable using 'insmod'.
631
632A boot setup command for the ncr53c8xx (sym53c8xx) driver begins with the
633driver name "ncr53c8xx="(sym53c8xx). The kernel syntax parser then expects
634an optionnal list of integers separated with comma followed by an optional
635list of comma-separated strings. Example of boot setup command under lilo
636prompt:
637
638lilo: linux root=/dev/hda2 ncr53c8xx=tags:4,sync:10,debug:0x200
639
640- enable tagged commands, up to 4 tagged commands queued.
641- set synchronous negotiation speed to 10 Mega-transfers / second.
642- set DEBUG_NEGO flag.
643
644Since comma seems not to be allowed when defining a string variable using
645'insmod', the driver also accepts <space> as option separator.
646The following command will install driver module with the same options as
647above.
648
649 insmod ncr53c8xx.o ncr53c8xx="tags:4 sync:10 debug:0x200"
650
651For the moment, the integer list of arguments is discarded by the driver.
652It will be used in the future in order to allow a per controller setup.
653
654Each string argument must be specified as "keyword:value". Only lower-case
655characters and digits are allowed.
656
657In a system that contains multiple 53C8xx adapters insmod will install the
658specified driver on each adapter. To exclude a chip use the 'excl' keyword.
659
660The sequence of commands,
661
662 insmod sym53c8xx sym53c8xx=excl:0x1400
663 insmod ncr53c8xx
664
665installs the sym53c8xx driver on all adapters except the one at IO port
666address 0x1400 and then installs the ncr53c8xx driver to the adapter at IO
667port address 0x1400.
668
669
67010.2 Available arguments
671
67210.2.1 Master parity checking
673 mpar:y enabled
674 mpar:n disabled
675
67610.2.2 Scsi parity checking
677 spar:y enabled
678 spar:n disabled
679
68010.2.3 Scsi disconnections
681 disc:y enabled
682 disc:n disabled
683
68410.2.4 Special features
685 Only apply to 810A, 825A, 860, 875 and 895 controllers.
686 Have no effect with other ones.
687 specf:y (or 1) enabled
688 specf:n (or 0) disabled
689 specf:3 enabled except Memory Write And Invalidate
690 The default driver setup is 'specf:3'. As a consequence, option 'specf:y'
691 must be specified in the boot setup command to enable Memory Write And
692 Invalidate.
693
69410.2.5 Ultra SCSI support
695 Only apply to 860, 875, 895, 895a, 896, 1010 and 1010_66 controllers.
696 Have no effect with other ones.
697 ultra:n All ultra speeds enabled
698 ultra:2 Ultra2 enabled
699 ultra:1 Ultra enabled
700 ultra:0 Ultra speeds disabled
701
70210.2.6 Default number of tagged commands
703 tags:0 (or tags:1 ) tagged command queuing disabled
704 tags:#tags (#tags > 1) tagged command queuing enabled
705 #tags will be truncated to the max queued commands configuration parameter.
706 This option also allows to specify a command queue depth for each device
707 that support tagged command queueing.
708 Example:
709 ncr53c8xx=tags:10/t2t3q16-t5q24/t1u2q32
710 will set devices queue depth as follow:
711 - controller #0 target #2 and target #3 -> 16 commands,
712 - controller #0 target #5 -> 24 commands,
713 - controller #1 target #1 logical unit #2 -> 32 commands,
714 - all other logical units (all targets, all controllers) -> 10 commands.
715
71610.2.7 Default synchronous period factor
717 sync:255 disabled (asynchronous transfer mode)
718 sync:#factor
719 #factor = 10 Ultra-2 SCSI 40 Mega-transfers / second
720 #factor = 11 Ultra-2 SCSI 33 Mega-transfers / second
721 #factor < 25 Ultra SCSI 20 Mega-transfers / second
722 #factor < 50 Fast SCSI-2
723
724 In all cases, the driver will use the minimum transfer period supported by
725 controllers according to NCR53C8XX chip type.
726
72710.2.8 Negotiate synchronous with all devices
728 (force sync nego)
729 fsn:y enabled
730 fsn:n disabled
731
73210.2.9 Verbosity level
733 verb:0 minimal
734 verb:1 normal
735 verb:2 too much
736
73710.2.10 Debug mode
738 debug:0 clear debug flags
739 debug:#x set debug flags
740 #x is an integer value combining the following power-of-2 values:
741 DEBUG_ALLOC 0x1
742 DEBUG_PHASE 0x2
743 DEBUG_POLL 0x4
744 DEBUG_QUEUE 0x8
745 DEBUG_RESULT 0x10
746 DEBUG_SCATTER 0x20
747 DEBUG_SCRIPT 0x40
748 DEBUG_TINY 0x80
749 DEBUG_TIMING 0x100
750 DEBUG_NEGO 0x200
751 DEBUG_TAGS 0x400
752 DEBUG_FREEZE 0x800
753 DEBUG_RESTART 0x1000
754
755 You can play safely with DEBUG_NEGO. However, some of these flags may
756 generate bunches of syslog messages.
757
75810.2.11 Burst max
759 burst:0 burst disabled
760 burst:255 get burst length from initial IO register settings.
761 burst:#x burst enabled (1<<#x burst transfers max)
762 #x is an integer value which is log base 2 of the burst transfers max.
763 The NCR53C875 and NCR53C825A support up to 128 burst transfers (#x = 7).
764 Other chips only support up to 16 (#x = 4).
765 This is a maximum value. The driver set the burst length according to chip
766 and revision ids. By default the driver uses the maximum value supported
767 by the chip.
768
76910.2.12 LED support
770 led:1 enable LED support
771 led:0 disable LED support
772 Donnot enable LED support if your scsi board does not use SDMS BIOS.
773 (See 'Configuration parameters')
774
77510.2.13 Max wide
776 wide:1 wide scsi enabled
777 wide:0 wide scsi disabled
778 Some scsi boards use a 875 (ultra wide) and only supply narrow connectors.
779 If you have connected a wide device with a 50 pins to 68 pins cable
780 converter, any accepted wide negotiation will break further data transfers.
781 In such a case, using "wide:0" in the bootup command will be helpfull.
782
78310.2.14 Differential mode
784 diff:0 never set up diff mode
785 diff:1 set up diff mode if BIOS set it
786 diff:2 always set up diff mode
787 diff:3 set diff mode if GPIO3 is not set
788
78910.2.15 IRQ mode
790 irqm:0 always open drain
791 irqm:1 same as initial settings (assumed BIOS settings)
792 irqm:2 always totem pole
793 irqm:0x10 driver will not use SA_SHIRQ flag when requesting irq
794 irqm:0x20 driver will not use SA_INTERRUPT flag when requesting irq
795
796 (Bits 0x10 and 0x20 can be combined with hardware irq mode option)
797
79810.2.16 Reverse probe
799 revprob:n probe chip ids from the PCI configuration in this order:
800 810, 815, 820, 860, 875, 885, 895, 896
801 revprob:y probe chip ids in the reverse order.
802
80310.2.17 Fix up PCI configuration space
804 pcifix:<option bits>
805
806 Available option bits:
807 0x0: No attempt to fix PCI configuration space registers values.
808 0x1: Set PCI cache-line size register if not set.
809 0x2: Set write and invalidate bit in PCI command register.
810 0x4: Increase if necessary PCI latency timer according to burst max.
811
812 Use 'pcifix:7' in order to allow the driver to fix up all PCI features.
813
81410.2.18 Serial NVRAM
815 nvram:n do not look for serial NVRAM
816 nvram:y test controllers for onboard serial NVRAM
817 (alternate binary form)
818 mvram=<bits options>
819 0x01 look for NVRAM (equivalent to nvram=y)
820 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices
821 0x04 ignore NVRAM "Wide negotiation" parameter for all devices
822 0x08 ignore NVRAM "Scan at boot time" parameter for all devices
823 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only)
824
82510.2.19 Check SCSI BUS
826 buschk:<option bits>
827
828 Available option bits:
829 0x0: No check.
830 0x1: Check and do not attach the controller on error.
831 0x2: Check and just warn on error.
832 0x4: Disable SCSI bus integrity checking.
833
83410.2.20 Exclude a host from being attached
835 excl=<io_address>
836
837 Prevent host at a given io address from being attached.
838 For example 'ncr53c8xx=excl:0xb400,excl:0xc000' indicate to the
839 ncr53c8xx driver not to attach hosts at address 0xb400 and 0xc000.
840
84110.2.21 Suggest a default SCSI id for hosts
842 hostid:255 no id suggested.
843 hostid:#x (0 < x < 7) x suggested for hosts SCSI id.
844
845 If a host SCSI id is available from the NVRAM, the driver will ignore
846 any value suggested as boot option. Otherwise, if a suggested value
847 different from 255 has been supplied, it will use it. Otherwise, it will
848 try to deduce the value previously set in the hardware and use value
849 7 if the hardware value is zero.
850
85110.2.22 Enable use of IMMEDIATE ARBITRATION
852 (only supported by the sym53c8xx driver. See 10.7 for more details)
853 iarb:0 do not use this feature.
854 iarb:#x use this feature according to bit fields as follow:
855
856 bit 0 (1) : enable IARB each time the initiator has been reselected
857 when it arbitrated for the SCSI BUS.
858 (#x >> 4) : maximum number of successive settings of IARB if the initiator
859 win arbitration and it has other commands to send to a device.
860
861Boot fail safe
862 safe:y load the following assumed fail safe initial setup
863
864 master parity disabled mpar:n
865 scsi parity enabled spar:y
866 disconnections not allowed disc:n
867 special features disabled specf:n
868 ultra scsi disabled ultra:n
869 force sync negotiation disabled fsn:n
870 reverse probe disabled revprob:n
871 PCI fix up disabled pcifix:0
872 serial NVRAM enabled nvram:y
873 verbosity level 2 verb:2
874 tagged command queuing disabled tags:0
875 synchronous negotiation disabled sync:255
876 debug flags none debug:0
877 burst length from BIOS settings burst:255
878 LED support disabled led:0
879 wide support disabled wide:0
880 settle time 10 seconds settle:10
881 differential support from BIOS settings diff:1
882 irq mode from BIOS settings irqm:1
883 SCSI BUS check do not attach on error buschk:1
884 immediate arbitration disabled iarb:0
885
88610.3 Advised boot setup commands
887
888If the driver has been configured with default options, the equivalent
889boot setup is:
890
891 ncr53c8xx=mpar:y,spar:y,disc:y,specf:3,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\
892 tags:0,sync:50,debug:0,burst:7,led:0,wide:1,settle:2,diff:0,irqm:0
893
894For an installation diskette or a safe but not fast system,
895boot setup can be:
896
897 ncr53c8xx=safe:y,mpar:y,disc:y
898 ncr53c8xx=safe:y,disc:y
899 ncr53c8xx=safe:y,mpar:y
900 ncr53c8xx=safe:y
901
902My personnal system works flawlessly with the following equivalent setup:
903
904 ncr53c8xx=mpar:y,spar:y,disc:y,specf:1,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\
905 tags:32,sync:12,debug:0,burst:7,led:1,wide:1,settle:2,diff:0,irqm:0
906
907The driver prints its actual setup when verbosity level is 2. You can try
908"ncr53c8xx=verb:2" to get the "static" setup of the driver, or add "verb:2"
909to your boot setup command in order to check the actual setup the driver is
910using.
911
91210.4 PCI configuration fix-up boot option
913
914pcifix:<option bits>
915
916Available option bits:
917 0x1: Set PCI cache-line size register if not set.
918 0x2: Set write and invalidate bit in PCI command register.
919
920Use 'pcifix:3' in order to allow the driver to fix both PCI features.
921
922These options only apply to new SYMBIOS chips 810A, 825A, 860, 875
923and 895 and are only supported for Pentium and 486 class processors.
924Recent SYMBIOS 53C8XX scsi processors are able to use PCI read multiple
925and PCI write and invalidate commands. These features require the
926cache line size register to be properly set in the PCI configuration
927space of the chips. On the other hand, chips will use PCI write and
928invalidate commands only if the corresponding bit is set to 1 in the
929PCI command register.
930
931Not all PCI bioses set the PCI cache line register and the PCI write and
932invalidate bit in the PCI configuration space of 53C8XX chips.
933Optimized PCI accesses may be broken for some PCI/memory controllers or
934make problems with some PCI boards.
935
936This fix-up worked flawlessly on my previous system.
937(MB Triton HX / 53C875 / 53C810A)
938I use these options at my own risks as you will do if you decide to
939use them too.
940
941
94210.5 Serial NVRAM support boot option
943
944nvram:n do not look for serial NVRAM
945nvram:y test controllers for onboard serial NVRAM
946
947This option can also been entered as an hexadecimal value that allows
948to control what information the driver will get from the NVRAM and what
949information it will ignore.
950For details see '17. Serial NVRAM support'.
951
952When this option is enabled, the driver tries to detect all boards using
953a Serial NVRAM. This memory is used to hold user set up parameters.
954
955The parameters the driver is able to get from the NVRAM depend on the
956data format used, as follow:
957
958 Tekram format Symbios format
959General and host parameters
960 Boot order N Y
961 Host SCSI ID Y Y
962 SCSI parity checking Y Y
963 Verbose boot messages N Y
964SCSI devices parameters
965 Synchronous transfer speed Y Y
966 Wide 16 / Narrow Y Y
967 Tagged Command Queuing enabled Y Y
968 Disconnections enabled Y Y
969 Scan at boot time N Y
970
971In order to speed up the system boot, for each device configured without
972the "scan at boot time" option, the driver forces an error on the
973first TEST UNIT READY command received for this device.
974
975Some SDMS BIOS revisions seem to be unable to boot cleanly with very fast
976hard disks. In such a situation you cannot configure the NVRAM with
977optimized parameters value.
978
979The 'nvram' boot option can be entered in hexadecimal form in order
980to ignore some options configured in the NVRAM, as follow:
981
982mvram=<bits options>
983 0x01 look for NVRAM (equivalent to nvram=y)
984 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices
985 0x04 ignore NVRAM "Wide negotiation" parameter for all devices
986 0x08 ignore NVRAM "Scan at boot time" parameter for all devices
987 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only)
988
989Option 0x80 is only supported by the sym53c8xx driver and is disabled by
990default. Result is that, by default (option not set), the sym53c8xx driver
991will not attach controllers set to OFF in the NVRAM.
992
993The ncr53c8xx always tries to attach all the controllers. Option 0x80 has
994not been added to the ncr53c8xx driver, since it has been reported to
995confuse users who use this driver since a long time. If you desire a
996controller not to be attached by the ncr53c8xx driver at Linux boot, you
997must use the 'excl' driver boot option.
998
99910.6 SCSI BUS checking boot option.
1000
1001When this option is set to a non-zero value, the driver checks SCSI lines
1002logic state, 100 micro-seconds after having asserted the SCSI RESET line.
1003The driver just reads SCSI lines and checks all lines read FALSE except RESET.
1004Since SCSI devices shall release the BUS at most 800 nano-seconds after SCSI
1005RESET has been asserted, any signal to TRUE may indicate a SCSI BUS problem.
1006Unfortunately, the following common SCSI BUS problems are not detected:
1007- Only 1 terminator installed.
1008- Misplaced terminators.
1009- Bad quality terminators.
1010On the other hand, either bad cabling, broken devices, not conformant
1011devices, ... may cause a SCSI signal to be wrong when te driver reads it.
1012
101310.7 IMMEDIATE ARBITRATION boot option
1014
1015This option is only supported by the SYM53C8XX driver (not by the NCR53C8XX).
1016
1017SYMBIOS 53C8XX chips are able to arbitrate for the SCSI BUS as soon as they
1018have detected an expected disconnection (BUS FREE PHASE). For this process
1019to be started, bit 1 of SCNTL1 IO register must be set when the chip is
1020connected to the SCSI BUS.
1021
1022When this feature has been enabled for the current connection, the chip has
1023every chance to win arbitration if only devices with lower priority are
1024competing for the SCSI BUS. By the way, when the chip is using SCSI id 7,
1025then it will for sure win the next SCSI BUS arbitration.
1026
1027Since, there is no way to know what devices are trying to arbitrate for the
1028BUS, using this feature can be extremely unfair. So, you are not advised
1029to enable it, or at most enable this feature for the case the chip lost
1030the previous arbitration (boot option 'iarb:1').
1031
1032This feature has the following advantages:
1033
1034a) Allow the initiator with ID 7 to win arbitration when it wants so.
1035b) Overlap at least 4 micro-seconds of arbitration time with the execution
1036 of SCRIPTS that deal with the end of the current connection and that
1037 starts the next job.
1038
1039Hmmm... But (a) may just prevent other devices from reselecting the initiator,
1040and delay data transfers or status/completions, and (b) may just waste
1041SCSI BUS bandwidth if the SCRIPTS execution lasts more than 4 micro-seconds.
1042
1043The use of IARB needs the SCSI_NCR_IARB_SUPPORT option to have been defined
1044at compile time and the 'iarb' boot option to have been set to a non zero
1045value at boot time. It is not that useful for real work, but can be used
1046to stress SCSI devices or for some applications that can gain advantage of
1047it. By the way, if you experience badnesses like 'unexpected disconnections',
1048'bad reselections', etc... when using IARB on heavy IO load, you should not
1049be surprised, because force-feeding anything and blocking its arse at the
1050same time cannot work for a long time. :-))
1051
1052
105311. Some constants and flags of the ncr53c8xx.h header file
1054
1055Some of these are defined from the configuration parameters. To
1056change other "defines", you must edit the header file. Do that only
1057if you know what you are doing.
1058
1059SCSI_NCR_SETUP_SPECIAL_FEATURES (default: defined)
1060 If defined, the driver will enable some special features according
1061 to chip and revision id.
1062 For 810A, 860, 825A, 875 and 895 scsi chips, this option enables
1063 support of features that reduce load of PCI bus and memory accesses
1064 during scsi transfer processing: burst op-code fetch, read multiple,
1065 read line, prefetch, cache line, write and invalidate,
1066 burst 128 (875 only), large dma fifo (875 only), offset 16 (875 only).
1067 Can be changed by the following boot setup command:
1068 ncr53c8xx=specf:n
1069
1070SCSI_NCR_IOMAPPED (default: not defined)
1071 If defined, normal I/O is forced.
1072
1073SCSI_NCR_SHARE_IRQ (default: defined)
1074 If defined, request shared IRQ.
1075
1076SCSI_NCR_MAX_TAGS (default: 8)
1077 Maximum number of simultaneous tagged commands to a device.
1078 Can be changed by "settags <target> <maxtags>"
1079
1080SCSI_NCR_SETUP_DEFAULT_SYNC (default: 50)
1081 Transfer period factor the driver will use at boot time for synchronous
1082 negotiation. 0 means asynchronous.
1083 Can be changed by "setsync <target> <period factor>"
1084
1085SCSI_NCR_SETUP_DEFAULT_TAGS (default: 8)
1086 Default number of simultaneous tagged commands to a device.
1087 < 1 means tagged command queuing disabled at start-up.
1088
1089SCSI_NCR_ALWAYS_SIMPLE_TAG (default: defined)
1090 Use SIMPLE TAG for read and write commands.
1091 Can be changed by "setorder <ordered|simple|default>"
1092
1093SCSI_NCR_SETUP_DISCONNECTION (default: defined)
1094 If defined, targets are allowed to disconnect.
1095
1096SCSI_NCR_SETUP_FORCE_SYNC_NEGO (default: not defined)
1097 If defined, synchronous negotiation is tried for all SCSI-2 devices.
1098 Can be changed by "setsync <target> <period>"
1099
1100SCSI_NCR_SETUP_MASTER_PARITY (default: defined)
1101 If defined, master parity checking is enabled.
1102
1103SCSI_NCR_SETUP_MASTER_PARITY (default: defined)
1104 If defined, SCSI parity checking is enabled.
1105
1106SCSI_NCR_PROFILE_SUPPORT (default: not defined)
1107 If defined, profiling information is gathered.
1108
1109SCSI_NCR_MAX_SCATTER (default: 128)
1110 Scatter list size of the driver ccb.
1111
1112SCSI_NCR_MAX_TARGET (default: 16)
1113 Max number of targets per host.
1114
1115SCSI_NCR_MAX_HOST (default: 2)
1116 Max number of host controllers.
1117
1118SCSI_NCR_SETTLE_TIME (default: 2)
1119 Number of seconds the driver will wait after reset.
1120
1121SCSI_NCR_TIMEOUT_ALERT (default: 3)
1122 If a pending command will time out after this amount of seconds,
1123 an ordered tag is used for the next command.
1124 Avoids timeouts for unordered tagged commands.
1125
1126SCSI_NCR_CAN_QUEUE (default: 7*SCSI_NCR_MAX_TAGS)
1127 Max number of commands that can be queued to a host.
1128
1129SCSI_NCR_CMD_PER_LUN (default: SCSI_NCR_MAX_TAGS)
1130 Max number of commands queued to a host for a device.
1131
1132SCSI_NCR_SG_TABLESIZE (default: SCSI_NCR_MAX_SCATTER-1)
1133 Max size of the Linux scatter/gather list.
1134
1135SCSI_NCR_MAX_LUN (default: 8)
1136 Max number of LUNs per target.
1137
1138
113912. Installation
1140
1141This driver is part of the linux kernel distribution.
1142Driver files are located in the sub-directory "drivers/scsi" of the
1143kernel source tree.
1144
1145Driver files:
1146
1147 README.ncr53c8xx : this file
1148 ChangeLog.ncr53c8xx : change log
1149 ncr53c8xx.h : definitions
1150 ncr53c8xx.c : the driver code
1151
1152New driver versions are made available separately in order to allow testing
1153changes and new features prior to including them into the linux kernel
1154distribution. The following URL provides informations on latest avalaible
1155patches:
1156
1157 ftp://ftp.tux.org/pub/people/gerard-roudier/README
1158
1159
116013. Architecture dependent features.
1161
1162<Not yet written>
1163
1164
116514. Known problems
1166
116714.1 Tagged commands with Iomega Jaz device
1168
1169I have not tried this device, however it has been reported to me the
1170following: This device is capable of Tagged command queuing. However
1171while spinning up, it rejects Tagged commands. This behaviour is
1172conforms to 6.8.2 of SCSI-2 specifications. The current behaviour of
1173the driver in that situation is not satisfying. So do not enable
1174Tagged command queuing for devices that are able to spin down. The
1175other problem that may appear is timeouts. The only way to avoid
1176timeouts seems to edit linux/drivers/scsi/sd.c and to increase the
1177current timeout values.
1178
117914.2 Device names change when another controller is added.
1180
1181When you add a new NCR53C8XX chip based controller to a system that already
1182has one or more controllers of this family, it may happen that the order
1183the driver registers them to the kernel causes problems due to device
1184name changes.
1185When at least one controller uses NvRAM, SDMS BIOS version 4 allows you to
1186define the order the BIOS will scan the scsi boards. The driver attaches
1187controllers according to BIOS information if NvRAM detect option is set.
1188
1189If your controllers do not have NvRAM, you can:
1190
1191- Ask the driver to probe chip ids in reverse order from the boot command
1192 line: ncr53c8xx=revprob:y
1193- Make appropriate changes in the fstab.
1194- Use the 'scsidev' tool from Eric Youngdale.
1195
119614.3 Using only 8 bit devices with a WIDE SCSI controller.
1197
1198When only 8 bit NARROW devices are connected to a 16 bit WIDE SCSI controller,
1199you must ensure that lines of the wide part of the SCSI BUS are pulled-up.
1200This can be achieved by ENABLING the WIDE TERMINATOR portion of the SCSI
1201controller card.
1202The TYAN 1365 documentation revision 1.2 is not correct about such settings.
1203(page 10, figure 3.3).
1204
120514.4 Possible data corruption during a Memory Write and Invalidate
1206
1207This problem is described in SYMBIOS DEL 397, Part Number 69-039241, ITEM 4.
1208
1209In some complex situations, 53C875 chips revision <= 3 may start a PCI
1210Write and Invalidate Command at a not cache-line-aligned 4 DWORDS boundary.
1211This is only possible when Cache Line Size is 8 DWORDS or greater.
1212Pentium systems use a 8 DWORDS cache line size and so are concerned by
1213this chip bug, unlike i486 systems that use a 4 DWORDS cache line size.
1214
1215When this situation occurs, the chip may complete the Write and Invalidate
1216command after having only filled part of the last cache line involved in
1217the transfer, leaving to data corruption the remainder of this cache line.
1218
1219Not using Write And Invalidate obviously gets rid of this chip bug, and so
1220it is now the default setting of the driver.
1221However, for people like me who want to enable this feature, I have added
1222part of a work-around suggested by SYMBIOS. This work-around resets the
1223addressing logic when the DATA IN phase is entered and so prevents the bug
1224from being triggered for the first SCSI MOVE of the phase. This work-around
1225should be enough according to the following:
1226
1227The only driver internal data structure that is greater than 8 DWORDS and
1228that is moved by the SCRIPTS processor is the 'CCB header' that contains
1229the context of the SCSI transfer. This data structure is aligned on 8 DWORDS
1230boundary (Pentium Cache Line Size), and so is immune to this chip bug, at
1231least on Pentium systems.
1232But the conditions of this bug can be met when a SCSI read command is
1233performed using a buffer that is 4 DWORDS but not cache-line aligned.
1234This cannot happen under Linux when scatter/gather lists are used since
1235they only refer to system buffers that are well aligned. So, a work around
1236may only be needed under Linux when a scatter/gather list is not used and
1237when the SCSI DATA IN phase is reentered after a phase mismatch.
1238
123914.5 IRQ sharing problems
1240
1241When an IRQ is shared by devices that are handled by different drivers, it
1242may happen that one driver complains about the request of the IRQ having
1243failed. Inder Linux-2.0, this may be due to one driver having requested the
1244IRQ using the SA_INTERRUPT flag but some other having requested the same IRQ
1245without this flag. Under both Linux-2.0 and linux-2.2, this may be caused by
1246one driver not having requested the IRQ with the SA_SHIRQ flag.
1247
1248By default, the ncr53c8xx and sym53c8xx drivers request IRQs with both the
1249SA_INTERRUPT and the SA_SHIRQ flag under Linux-2.0 and with only the SA_SHIRQ
1250flag under Linux-2.2.
1251
1252Under Linux-2.0, you can disable use of SA_INTERRUPT flag from the boot
1253command line by using the following option:
1254
1255 ncr53c8xx=irqm:0x20 (for the generic ncr53c8xx driver)
1256 sym53c8xx=irqm:0x20 (for the sym53c8xx driver)
1257
1258If this does not fix the problem, then you may want to check how all other
1259drivers are requesting the IRQ and report the problem. Note that if at least
1260a single driver does not request the IRQ with the SA_SHIRQ flag (share IRQ),
1261then the request of the IRQ obviously will not succeed for all the drivers.
1262
126315. SCSI problem troubleshooting
1264
126515.1 Problem tracking
1266
1267Most SCSI problems are due to a non conformant SCSI bus or to buggy
1268devices. If infortunately you have SCSI problems, you can check the
1269following things:
1270
1271- SCSI bus cables
1272- terminations at both end of the SCSI chain
1273- linux syslog messages (some of them may help you)
1274
1275If you do not find the source of problems, you can configure the
1276driver with no features enabled.
1277
1278- only asynchronous data transfers
1279- tagged commands disabled
1280- disconnections not allowed
1281
1282Now, if your SCSI bus is ok, your system have every chance to work
1283with this safe configuration but performances will not be optimal.
1284
1285If it still fails, then you can send your problem description to
1286appropriate mailing lists or news-groups. Send me a copy in order to
1287be sure I will receive it. Obviously, a bug in the driver code is
1288possible.
1289
1290 My email address: Gerard Roudier <groudier@free.fr>
1291
1292Allowing disconnections is important if you use several devices on
1293your SCSI bus but often causes problems with buggy devices.
1294Synchronous data transfers increases throughput of fast devices like
1295hard disks. Good SCSI hard disks with a large cache gain advantage of
1296tagged commands queuing.
1297
1298Try to enable one feature at a time with control commands. For example:
1299
1300- echo "setsync all 25" >/proc/scsi/ncr53c8xx/0
1301 Will enable fast synchronous data transfer negotiation for all targets.
1302
1303- echo "setflag 3" >/proc/scsi/ncr53c8xx/0
1304 Will reset flags (no_disc) for target 3, and so will allow it to disconnect
1305 the SCSI Bus.
1306
1307- echo "settags 3 8" >/proc/scsi/ncr53c8xx/0
1308 Will enable tagged command queuing for target 3 if that device supports it.
1309
1310Once you have found the device and the feature that cause problems, just
1311disable that feature for that device.
1312
131315.2 Understanding hardware error reports
1314
1315When the driver detects an unexpected error condition, it may display a
1316message of the following pattern.
1317
1318sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000).
1319sym53c876-0: script cmd = 19000000
1320sym53c876-0: regdump: da 10 80 95 47 0f 01 07 75 01 81 21 80 01 09 00.
1321
1322Some fields in such a message may help you understand the cause of the
1323problem, as follows:
1324
1325sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000).
1326............A.........B.C....D.E..F....G.H.......I.....J...K.......
1327
1328Field A : target number.
1329 SCSI ID of the device the controller was talking with at the moment the
1330 error occurs.
1331
1332Field B : DSTAT io register (DMA STATUS)
1333 Bit 0x40 : MDPE Master Data Parity Error
1334 Data parity error detected on the PCI BUS.
1335 Bit 0x20 : BF Bus Fault
1336 PCI bus fault condition detected
1337 Bit 0x01 : IID Illegal Instruction Detected
1338 Set by the chip when it detects an Illegal Instruction format
1339 on some condition that makes an instruction illegal.
1340 Bit 0x80 : DFE Dma Fifo Empty
1341 Pure status bit that does not indicate an error.
1342 If the reported DSTAT value contains a combination of MDPE (0x40),
1343 BF (0x20), then the cause may be likely due to a PCI BUS problem.
1344
1345Field C : SIST io register (SCSI Interrupt Status)
1346 Bit 0x08 : SGE SCSI GROSS ERROR
1347 Indicates that the chip detected a severe error condition
1348 on the SCSI BUS that prevents the SCSI protocol from functioning
1349 properly.
1350 Bit 0x04 : UDC Unexpected Disconnection
1351 Indicates that the device released the SCSI BUS when the chip
1352 was not expecting this to happen. A device may behave so to
1353 indicate the SCSI initiator that an error condition not reportable using the SCSI protocol has occurred.
1354 Bit 0x02 : RST SCSI BUS Reset
1355 Generally SCSI targets do not reset the SCSI BUS, although any
1356 device on the BUS can reset it at any time.
1357 Bit 0x01 : PAR Parity
1358 SCSI parity error detected.
1359 On a faulty SCSI BUS, any error condition among SGE (0x08), UDC (0x04) and
1360 PAR (0x01) may be detected by the chip. If your SCSI system sometimes
1361 encounters such error conditions, especially SCSI GROSS ERROR, then a SCSI
1362 BUS problem is likely the cause of these errors.
1363
1364For fields D,E,F,G and H, you may look into the sym53c8xx_defs.h file
1365that contains some minimal comments on IO register bits.
1366Field D : SOCL Scsi Output Control Latch
1367 This register reflects the state of the SCSI control lines the
1368 chip want to drive or compare against.
1369Field E : SBCL Scsi Bus Control Lines
1370 Actual value of control lines on the SCSI BUS.
1371Field F : SBDL Scsi Bus Data Lines
1372 Actual value of data lines on the SCSI BUS.
1373Field G : SXFER SCSI Transfer
1374 Contains the setting of the Synchronous Period for output and
1375 the current Synchronous offset (offset 0 means asynchronous).
1376Field H : SCNTL3 Scsi Control Register 3
1377 Contains the setting of timing values for both asynchronous and
1378 synchronous data transfers.
1379
1380Understanding Fields I, J, K and dumps requires to have good knowledge of
1381SCSI standards, chip cores functionnals and internal driver data structures.
1382You are not required to decode and understand them, unless you want to help
1383maintain the driver code.
1384
138516. Synchonous transfer negotiation tables
1386
1387Tables below have been created by calling the routine the driver uses
1388for synchronisation negotiation timing calculation and chip setting.
1389The first table corresponds to Ultra chips 53875 and 53C860 with 80 MHz
1390clock and 5 clock divisors.
1391The second one has been calculated by setting the scsi clock to 40 Mhz
1392and using 4 clock divisors and so applies to all NCR53C8XX chips in fast
1393SCSI-2 mode.
1394
1395Periods are in nano-seconds and speeds are in Mega-transfers per second.
13961 Mega-transfers/second means 1 MB/s with 8 bits SCSI and 2 MB/s with
1397Wide16 SCSI.
1398
139916.1 Synchronous timings for 53C895, 53C875 and 53C860 SCSI controllers
1400
1401 ----------------------------------------------
1402 Negotiated NCR settings
1403 Factor Period Speed Period Speed
1404 ------ ------ ------ ------ ------
1405 10 25 40.000 25 40.000 (53C895 only)
1406 11 30.2 33.112 31.25 32.000 (53C895 only)
1407 12 50 20.000 50 20.000
1408 13 52 19.230 62 16.000
1409 14 56 17.857 62 16.000
1410 15 60 16.666 62 16.000
1411 16 64 15.625 75 13.333
1412 17 68 14.705 75 13.333
1413 18 72 13.888 75 13.333
1414 19 76 13.157 87 11.428
1415 20 80 12.500 87 11.428
1416 21 84 11.904 87 11.428
1417 22 88 11.363 93 10.666
1418 23 92 10.869 93 10.666
1419 24 96 10.416 100 10.000
1420 25 100 10.000 100 10.000
1421 26 104 9.615 112 8.888
1422 27 108 9.259 112 8.888
1423 28 112 8.928 112 8.888
1424 29 116 8.620 125 8.000
1425 30 120 8.333 125 8.000
1426 31 124 8.064 125 8.000
1427 32 128 7.812 131 7.619
1428 33 132 7.575 150 6.666
1429 34 136 7.352 150 6.666
1430 35 140 7.142 150 6.666
1431 36 144 6.944 150 6.666
1432 37 148 6.756 150 6.666
1433 38 152 6.578 175 5.714
1434 39 156 6.410 175 5.714
1435 40 160 6.250 175 5.714
1436 41 164 6.097 175 5.714
1437 42 168 5.952 175 5.714
1438 43 172 5.813 175 5.714
1439 44 176 5.681 187 5.333
1440 45 180 5.555 187 5.333
1441 46 184 5.434 187 5.333
1442 47 188 5.319 200 5.000
1443 48 192 5.208 200 5.000
1444 49 196 5.102 200 5.000
1445
1446
144716.2 Synchronous timings for fast SCSI-2 53C8XX controllers
1448
1449 ----------------------------------------------
1450 Negotiated NCR settings
1451 Factor Period Speed Period Speed
1452 ------ ------ ------ ------ ------
1453 25 100 10.000 100 10.000
1454 26 104 9.615 125 8.000
1455 27 108 9.259 125 8.000
1456 28 112 8.928 125 8.000
1457 29 116 8.620 125 8.000
1458 30 120 8.333 125 8.000
1459 31 124 8.064 125 8.000
1460 32 128 7.812 131 7.619
1461 33 132 7.575 150 6.666
1462 34 136 7.352 150 6.666
1463 35 140 7.142 150 6.666
1464 36 144 6.944 150 6.666
1465 37 148 6.756 150 6.666
1466 38 152 6.578 175 5.714
1467 39 156 6.410 175 5.714
1468 40 160 6.250 175 5.714
1469 41 164 6.097 175 5.714
1470 42 168 5.952 175 5.714
1471 43 172 5.813 175 5.714
1472 44 176 5.681 187 5.333
1473 45 180 5.555 187 5.333
1474 46 184 5.434 187 5.333
1475 47 188 5.319 200 5.000
1476 48 192 5.208 200 5.000
1477 49 196 5.102 200 5.000
1478
1479
148017. Serial NVRAM (added by Richard Waltham: dormouse@farsrobt.demon.co.uk)
1481
148217.1 Features
1483
1484Enabling serial NVRAM support enables detection of the serial NVRAM included
1485on Symbios and some Symbios compatible host adaptors, and Tekram boards. The
1486serial NVRAM is used by Symbios and Tekram to hold set up parameters for the
1487host adaptor and it's attached drives.
1488
1489The Symbios NVRAM also holds data on the boot order of host adaptors in a
1490system with more than one host adaptor. This enables the order of scanning
1491the cards for drives to be changed from the default used during host adaptor
1492detection.
1493
1494This can be done to a limited extent at the moment using "reverse probe" but
1495this only changes the order of detection of different types of cards. The
1496NVRAM boot order settings can do this as well as change the order the same
1497types of cards are scanned in, something "reverse probe" cannot do.
1498
1499Tekram boards using Symbios chips, DC390W/F/U, which have NVRAM are detected
1500and this is used to distinguish between Symbios compatible and Tekram host
1501adaptors. This is used to disable the Symbios compatible "diff" setting
1502incorrectly set on Tekram boards if the CONFIG_SCSI_53C8XX_SYMBIOS_COMPAT
1503configuration parameter is set enabling both Symbios and Tekram boards to be
1504used together with the Symbios cards using all their features, including
1505"diff" support. ("led pin" support for Symbios compatible cards can remain
1506enabled when using Tekram cards. It does nothing useful for Tekram host
1507adaptors but does not cause problems either.)
1508
1509
151017.2 Symbios NVRAM layout
1511
1512typical data at NVRAM address 0x100 (53c810a NVRAM)
1513-----------------------------------------------------------
151400 00
151564 01
15168e 0b
1517
151800 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00
1519
152004 00 0f 00 00 10 00 50 00 00 01 00 00 62
152104 00 03 00 00 10 00 58 00 00 01 00 00 63
152204 00 01 00 00 10 00 48 00 00 01 00 00 61
152300 00 00 00 00 00 00 00 00 00 00 00 00 00
1524
15250f 00 08 08 64 00 0a 00
15260f 00 08 08 64 00 0a 00
15270f 00 08 08 64 00 0a 00
15280f 00 08 08 64 00 0a 00
15290f 00 08 08 64 00 0a 00
15300f 00 08 08 64 00 0a 00
15310f 00 08 08 64 00 0a 00
15320f 00 08 08 64 00 0a 00
1533
15340f 00 08 08 64 00 0a 00
15350f 00 08 08 64 00 0a 00
15360f 00 08 08 64 00 0a 00
15370f 00 08 08 64 00 0a 00
15380f 00 08 08 64 00 0a 00
15390f 00 08 08 64 00 0a 00
15400f 00 08 08 64 00 0a 00
15410f 00 08 08 64 00 0a 00
1542
154300 00 00 00 00 00 00 00
154400 00 00 00 00 00 00 00
154500 00 00 00 00 00 00 00
154600 00 00 00 00 00 00 00
154700 00 00 00 00 00 00 00
154800 00 00 00 00 00 00 00
154900 00 00 00 00 00 00 00
155000 00 00 00 00 00 00 00
1551
155200 00 00 00 00 00 00 00
155300 00 00 00 00 00 00 00
155400 00 00 00 00 00 00 00
155500 00 00 00 00 00 00 00
155600 00 00 00 00 00 00 00
155700 00 00 00 00 00 00 00
155800 00 00 00 00 00 00 00
155900 00 00 00 00 00 00 00
1560
156100 00 00 00 00 00 00 00
156200 00 00 00 00 00 00 00
156300 00 00 00 00 00 00 00
1564
1565fe fe
156600 00
156700 00
1568-----------------------------------------------------------
1569NVRAM layout details
1570
1571NVRAM Address 0x000-0x0ff not used
1572 0x100-0x26f initialised data
1573 0x270-0x7ff not used
1574
1575general layout
1576
1577 header - 6 bytes,
1578 data - 356 bytes (checksum is byte sum of this data)
1579 trailer - 6 bytes
1580 ---
1581 total 368 bytes
1582
1583data area layout
1584
1585 controller set up - 20 bytes
1586 boot configuration - 56 bytes (4x14 bytes)
1587 device set up - 128 bytes (16x8 bytes)
1588 unused (spare?) - 152 bytes (19x8 bytes)
1589 ---
1590 total 356 bytes
1591
1592-----------------------------------------------------------
1593header
1594
159500 00 - ?? start marker
159664 01 - byte count (lsb/msb excludes header/trailer)
15978e 0b - checksum (lsb/msb excludes header/trailer)
1598-----------------------------------------------------------
1599controller set up
1600
160100 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00
1602 | | | |
1603 | | | -- host ID
1604 | | |
1605 | | --Removable Media Support
1606 | | 0x00 = none
1607 | | 0x01 = Bootable Device
1608 | | 0x02 = All with Media
1609 | |
1610 | --flag bits 2
1611 | 0x00000001= scan order hi->low
1612 | (default 0x00 - scan low->hi)
1613 --flag bits 1
1614 0x00000001 scam enable
1615 0x00000010 parity enable
1616 0x00000100 verbose boot msgs
1617
1618remaining bytes unknown - they do not appear to change in my
1619current set up for any of the controllers.
1620
1621default set up is identical for 53c810a and 53c875 NVRAM
1622(Removable Media added Symbios BIOS version 4.09)
1623-----------------------------------------------------------
1624boot configuration
1625
1626boot order set by order of the devices in this table
1627
162804 00 0f 00 00 10 00 50 00 00 01 00 00 62 -- 1st controller
162904 00 03 00 00 10 00 58 00 00 01 00 00 63 2nd controller
163004 00 01 00 00 10 00 48 00 00 01 00 00 61 3rd controller
163100 00 00 00 00 00 00 00 00 00 00 00 00 00 4th controller
1632 | | | | | | | |
1633 | | | | | | ---- PCI io port adr
1634 | | | | | --0x01 init/scan at boot time
1635 | | | | --PCI device/function number (0xdddddfff)
1636 | | ----- ?? PCI vendor ID (lsb/msb)
1637 ----PCI device ID (lsb/msb)
1638
1639?? use of this data is a guess but seems reasonable
1640
1641remaining bytes unknown - they do not appear to change in my
1642current set up
1643
1644default set up is identical for 53c810a and 53c875 NVRAM
1645-----------------------------------------------------------
1646device set up (up to 16 devices - includes controller)
1647
16480f 00 08 08 64 00 0a 00 - id 0
16490f 00 08 08 64 00 0a 00
16500f 00 08 08 64 00 0a 00
16510f 00 08 08 64 00 0a 00
16520f 00 08 08 64 00 0a 00
16530f 00 08 08 64 00 0a 00
16540f 00 08 08 64 00 0a 00
16550f 00 08 08 64 00 0a 00
1656
16570f 00 08 08 64 00 0a 00
16580f 00 08 08 64 00 0a 00
16590f 00 08 08 64 00 0a 00
16600f 00 08 08 64 00 0a 00
16610f 00 08 08 64 00 0a 00
16620f 00 08 08 64 00 0a 00
16630f 00 08 08 64 00 0a 00
16640f 00 08 08 64 00 0a 00 - id 15
1665 | | | | | |
1666 | | | | ----timeout (lsb/msb)
1667 | | | --synch period (0x?? 40 Mtrans/sec- fast 40) (probably 0x28)
1668 | | | (0x30 20 Mtrans/sec- fast 20)
1669 | | | (0x64 10 Mtrans/sec- fast )
1670 | | | (0xc8 5 Mtrans/sec)
1671 | | | (0x00 asynchronous)
1672 | | -- ?? max sync offset (0x08 in NVRAM on 53c810a)
1673 | | (0x10 in NVRAM on 53c875)
1674 | --device bus width (0x08 narrow)
1675 | (0x10 16 bit wide)
1676 --flag bits
1677 0x00000001 - disconnect enabled
1678 0x00000010 - scan at boot time
1679 0x00000100 - scan luns
1680 0x00001000 - queue tags enabled
1681
1682remaining bytes unknown - they do not appear to change in my
1683current set up
1684
1685?? use of this data is a guess but seems reasonable
1686(but it could be max bus width)
1687
1688default set up for 53c810a NVRAM
1689default set up for 53c875 NVRAM - bus width - 0x10
1690 - sync offset ? - 0x10
1691 - sync period - 0x30
1692-----------------------------------------------------------
1693?? spare device space (32 bit bus ??)
1694
169500 00 00 00 00 00 00 00 (19x8bytes)
1696.
1697.
169800 00 00 00 00 00 00 00
1699
1700default set up is identical for 53c810a and 53c875 NVRAM
1701-----------------------------------------------------------
1702trailer
1703
1704fe fe - ? end marker ?
170500 00
170600 00
1707
1708default set up is identical for 53c810a and 53c875 NVRAM
1709-----------------------------------------------------------
1710
1711
1712
171317.3 Tekram NVRAM layout
1714
1715nvram 64x16 (1024 bit)
1716
1717Drive settings
1718
1719Drive ID 0-15 (addr 0x0yyyy0 = device setup, yyyy = ID)
1720 (addr 0x0yyyy1 = 0x0000)
1721
1722 x x x x x x x x x x x x x x x x
1723 | | | | | | | | |
1724 | | | | | | | | ----- parity check 0 - off
1725 | | | | | | | | 1 - on
1726 | | | | | | | |
1727 | | | | | | | ------- sync neg 0 - off
1728 | | | | | | | 1 - on
1729 | | | | | | |
1730 | | | | | | --------- disconnect 0 - off
1731 | | | | | | 1 - on
1732 | | | | | |
1733 | | | | | ----------- start cmd 0 - off
1734 | | | | | 1 - on
1735 | | | | |
1736 | | | | -------------- tagged cmds 0 - off
1737 | | | | 1 - on
1738 | | | |
1739 | | | ---------------- wide neg 0 - off
1740 | | | 1 - on
1741 | | |
1742 --------------------------- sync rate 0 - 10.0 Mtrans/sec
1743 1 - 8.0
1744 2 - 6.6
1745 3 - 5.7
1746 4 - 5.0
1747 5 - 4.0
1748 6 - 3.0
1749 7 - 2.0
1750 7 - 2.0
1751 8 - 20.0
1752 9 - 16.7
1753 a - 13.9
1754 b - 11.9
1755
1756Global settings
1757
1758Host flags 0 (addr 0x100000, 32)
1759
1760 x x x x x x x x x x x x x x x x
1761 | | | | | | | | | | | |
1762 | | | | | | | | ----------- host ID 0x00 - 0x0f
1763 | | | | | | | |
1764 | | | | | | | ----------------------- support for 0 - off
1765 | | | | | | | > 2 drives 1 - on
1766 | | | | | | |
1767 | | | | | | ------------------------- support drives 0 - off
1768 | | | | | | > 1Gbytes 1 - on
1769 | | | | | |
1770 | | | | | --------------------------- bus reset on 0 - off
1771 | | | | | power on 1 - on
1772 | | | | |
1773 | | | | ----------------------------- active neg 0 - off
1774 | | | | 1 - on
1775 | | | |
1776 | | | -------------------------------- imm seek 0 - off
1777 | | | 1 - on
1778 | | |
1779 | | ---------------------------------- scan luns 0 - off
1780 | | 1 - on
1781 | |
1782 -------------------------------------- removable 0 - disable
1783 as BIOS dev 1 - boot device
1784 2 - all
1785
1786Host flags 1 (addr 0x100001, 33)
1787
1788 x x x x x x x x x x x x x x x x
1789 | | | | | |
1790 | | | --------- boot delay 0 - 3 sec
1791 | | | 1 - 5
1792 | | | 2 - 10
1793 | | | 3 - 20
1794 | | | 4 - 30
1795 | | | 5 - 60
1796 | | | 6 - 120
1797 | | |
1798 --------------------------- max tag cmds 0 - 2
1799 1 - 4
1800 2 - 8
1801 3 - 16
1802 4 - 32
1803
1804Host flags 2 (addr 0x100010, 34)
1805
1806 x x x x x x x x x x x x x x x x
1807 |
1808 ----- F2/F6 enable 0 - off ???
1809 1 - on ???
1810
1811checksum (addr 0x111111)
1812
1813checksum = 0x1234 - (sum addr 0-63)
1814
1815----------------------------------------------------------------------------
1816
1817default nvram data:
1818
18190x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000
18200x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000
18210x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000
18220x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000
1823
18240x0f07 0x0400 0x0001 0x0000 0x0000 0x0000 0x0000 0x0000
18250x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000
18260x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000
18270x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0xfbbc
1828
1829
183018. Support for Big Endian
1831
1832The PCI local bus has been primarily designed for x86 architecture.
1833As a consequence, PCI devices generally expect DWORDS using little endian
1834byte ordering.
1835
183618.1 Big Endian CPU
1837
1838In order to support NCR chips on a Big Endian architecture the driver has to
1839perform byte reordering each time it is needed. This feature has been
1840added to the driver by Cort <cort@cs.nmt.edu> and is available in driver
1841version 2.5 and later ones. For the moment Big Endian support has only
1842been tested on Linux/PPC (PowerPC).
1843
184418.2 NCR chip in Big Endian mode of operations
1845
1846It can be read in SYMBIOS documentation that some chips support a special
1847Big Endian mode, on paper: 53C815, 53C825A, 53C875, 53C875N, 53C895.
1848This mode of operations is not software-selectable, but needs pin named
1849BigLit to be pulled-up. Using this mode, most of byte reorderings should
1850be avoided when the driver is running on a Big Endian CPU.
1851Driver version 2.5 is also, in theory, ready for this feature.
1852
1853===============================================================================
1854End of NCR53C8XX driver README file