1The 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. Synchronous 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 earliest 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 instructions 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 118Useful 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 didn't 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_IOMAPPED (default answer: n) 566 Answer "y" if you suspect your mother board to not allow memory mapped I/O. 567 May slow down performance a little. This option is required by 568 Linux/PPC and is used no matter what you select here. Linux/PPC 569 suffers no performance loss with this option since all IO is memory 570 mapped anyway. 571 572CONFIG_SCSI_NCR53C8XX_DEFAULT_TAGS (default answer: 8) 573 Default tagged command queue depth. 574 575CONFIG_SCSI_NCR53C8XX_MAX_TAGS (default answer: 8) 576 This option allows you to specify the maximum number of tagged commands 577 that can be queued to a device. The maximum supported value is 32. 578 579CONFIG_SCSI_NCR53C8XX_SYNC (default answer: 5) 580 This option allows you to specify the frequency in MHz the driver 581 will use at boot time for synchronous data transfer negotiations. 582 This frequency can be changed later with the "setsync" control command. 583 0 means "asynchronous data transfers". 584 585CONFIG_SCSI_NCR53C8XX_FORCE_SYNC_NEGO (default answer: n) 586 Force synchronous negotiation for all SCSI-2 devices. 587 Some SCSI-2 devices do not report this feature in byte 7 of inquiry 588 response but do support it properly (TAMARACK scanners for example). 589 590CONFIG_SCSI_NCR53C8XX_NO_DISCONNECT (default and only reasonable answer: n) 591 If you suspect a device of yours does not properly support disconnections, 592 you can answer "y". Then, all SCSI devices will never disconnect the bus 593 even while performing long SCSI operations. 594 595CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT 596 Genuine SYMBIOS boards use GPIO0 in output for controller LED and GPIO3 597 bit as a flag indicating singled-ended/differential interface. 598 If all the boards of your system are genuine SYMBIOS boards or use 599 BIOS and drivers from SYMBIOS, you would want to enable this option. 600 This option must NOT be enabled if your system has at least one 53C8XX 601 based scsi board with a vendor-specific BIOS. 602 For example, Tekram DC-390/U, DC-390/W and DC-390/F scsi controllers 603 use a vendor-specific BIOS and are known to not use SYMBIOS compatible 604 GPIO wiring. So, this option must not be enabled if your system has 605 such a board installed. 606 607CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT 608 Enable support for reading the serial NVRAM data on Symbios and 609 some Symbios compatible cards, and Tekram DC390W/U/F cards. Useful for 610 systems with more than one Symbios compatible controller where at least 611 one has a serial NVRAM, or for a system with a mixture of Symbios and 612 Tekram cards. Enables setting the boot order of host adaptors 613 to something other than the default order or "reverse probe" order. 614 Also enables Symbios and Tekram cards to be distinguished so 615 CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT may be set in a system with a 616 mixture of Symbios and Tekram cards so the Symbios cards can make use of 617 the full range of Symbios features, differential, led pin, without 618 causing problems for the Tekram card(s). 619 62010. Boot setup commands 621 62210.1 Syntax 623 624Setup commands can be passed to the driver either at boot time or as a 625string variable using 'insmod'. 626 627A boot setup command for the ncr53c8xx (sym53c8xx) driver begins with the 628driver name "ncr53c8xx="(sym53c8xx). The kernel syntax parser then expects 629an optional list of integers separated with comma followed by an optional 630list of comma-separated strings. Example of boot setup command under lilo 631prompt: 632 633lilo: linux root=/dev/hda2 ncr53c8xx=tags:4,sync:10,debug:0x200 634 635- enable tagged commands, up to 4 tagged commands queued. 636- set synchronous negotiation speed to 10 Mega-transfers / second. 637- set DEBUG_NEGO flag. 638 639Since comma seems not to be allowed when defining a string variable using 640'insmod', the driver also accepts <space> as option separator. 641The following command will install driver module with the same options as 642above. 643 644 insmod ncr53c8xx.o ncr53c8xx="tags:4 sync:10 debug:0x200" 645 646For the moment, the integer list of arguments is discarded by the driver. 647It will be used in the future in order to allow a per controller setup. 648 649Each string argument must be specified as "keyword:value". Only lower-case 650characters and digits are allowed. 651 652In a system that contains multiple 53C8xx adapters insmod will install the 653specified driver on each adapter. To exclude a chip use the 'excl' keyword. 654 655The sequence of commands, 656 657 insmod sym53c8xx sym53c8xx=excl:0x1400 658 insmod ncr53c8xx 659 660installs the sym53c8xx driver on all adapters except the one at IO port 661address 0x1400 and then installs the ncr53c8xx driver to the adapter at IO 662port address 0x1400. 663 664 66510.2 Available arguments 666 66710.2.1 Master parity checking 668 mpar:y enabled 669 mpar:n disabled 670 67110.2.2 Scsi parity checking 672 spar:y enabled 673 spar:n disabled 674 67510.2.3 Scsi disconnections 676 disc:y enabled 677 disc:n disabled 678 67910.2.4 Special features 680 Only apply to 810A, 825A, 860, 875 and 895 controllers. 681 Have no effect with other ones. 682 specf:y (or 1) enabled 683 specf:n (or 0) disabled 684 specf:3 enabled except Memory Write And Invalidate 685 The default driver setup is 'specf:3'. As a consequence, option 'specf:y' 686 must be specified in the boot setup command to enable Memory Write And 687 Invalidate. 688 68910.2.5 Ultra SCSI support 690 Only apply to 860, 875, 895, 895a, 896, 1010 and 1010_66 controllers. 691 Have no effect with other ones. 692 ultra:n All ultra speeds enabled 693 ultra:2 Ultra2 enabled 694 ultra:1 Ultra enabled 695 ultra:0 Ultra speeds disabled 696 69710.2.6 Default number of tagged commands 698 tags:0 (or tags:1 ) tagged command queuing disabled 699 tags:#tags (#tags > 1) tagged command queuing enabled 700 #tags will be truncated to the max queued commands configuration parameter. 701 This option also allows to specify a command queue depth for each device 702 that support tagged command queueing. 703 Example: 704 ncr53c8xx=tags:10/t2t3q16-t5q24/t1u2q32 705 will set devices queue depth as follow: 706 - controller #0 target #2 and target #3 -> 16 commands, 707 - controller #0 target #5 -> 24 commands, 708 - controller #1 target #1 logical unit #2 -> 32 commands, 709 - all other logical units (all targets, all controllers) -> 10 commands. 710 71110.2.7 Default synchronous period factor 712 sync:255 disabled (asynchronous transfer mode) 713 sync:#factor 714 #factor = 10 Ultra-2 SCSI 40 Mega-transfers / second 715 #factor = 11 Ultra-2 SCSI 33 Mega-transfers / second 716 #factor < 25 Ultra SCSI 20 Mega-transfers / second 717 #factor < 50 Fast SCSI-2 718 719 In all cases, the driver will use the minimum transfer period supported by 720 controllers according to NCR53C8XX chip type. 721 72210.2.8 Negotiate synchronous with all devices 723 (force sync nego) 724 fsn:y enabled 725 fsn:n disabled 726 72710.2.9 Verbosity level 728 verb:0 minimal 729 verb:1 normal 730 verb:2 too much 731 73210.2.10 Debug mode 733 debug:0 clear debug flags 734 debug:#x set debug flags 735 #x is an integer value combining the following power-of-2 values: 736 DEBUG_ALLOC 0x1 737 DEBUG_PHASE 0x2 738 DEBUG_POLL 0x4 739 DEBUG_QUEUE 0x8 740 DEBUG_RESULT 0x10 741 DEBUG_SCATTER 0x20 742 DEBUG_SCRIPT 0x40 743 DEBUG_TINY 0x80 744 DEBUG_TIMING 0x100 745 DEBUG_NEGO 0x200 746 DEBUG_TAGS 0x400 747 DEBUG_FREEZE 0x800 748 DEBUG_RESTART 0x1000 749 750 You can play safely with DEBUG_NEGO. However, some of these flags may 751 generate bunches of syslog messages. 752 75310.2.11 Burst max 754 burst:0 burst disabled 755 burst:255 get burst length from initial IO register settings. 756 burst:#x burst enabled (1<<#x burst transfers max) 757 #x is an integer value which is log base 2 of the burst transfers max. 758 The NCR53C875 and NCR53C825A support up to 128 burst transfers (#x = 7). 759 Other chips only support up to 16 (#x = 4). 760 This is a maximum value. The driver set the burst length according to chip 761 and revision ids. By default the driver uses the maximum value supported 762 by the chip. 763 76410.2.12 LED support 765 led:1 enable LED support 766 led:0 disable LED support 767 Donnot enable LED support if your scsi board does not use SDMS BIOS. 768 (See 'Configuration parameters') 769 77010.2.13 Max wide 771 wide:1 wide scsi enabled 772 wide:0 wide scsi disabled 773 Some scsi boards use a 875 (ultra wide) and only supply narrow connectors. 774 If you have connected a wide device with a 50 pins to 68 pins cable 775 converter, any accepted wide negotiation will break further data transfers. 776 In such a case, using "wide:0" in the bootup command will be helpful. 777 77810.2.14 Differential mode 779 diff:0 never set up diff mode 780 diff:1 set up diff mode if BIOS set it 781 diff:2 always set up diff mode 782 diff:3 set diff mode if GPIO3 is not set 783 78410.2.15 IRQ mode 785 irqm:0 always open drain 786 irqm:1 same as initial settings (assumed BIOS settings) 787 irqm:2 always totem pole 788 irqm:0x10 driver will not use IRQF_SHARED flag when requesting irq 789 irqm:0x20 driver will not use IRQF_DISABLED flag when requesting irq 790 791 (Bits 0x10 and 0x20 can be combined with hardware irq mode option) 792 79310.2.16 Reverse probe 794 revprob:n probe chip ids from the PCI configuration in this order: 795 810, 815, 820, 860, 875, 885, 895, 896 796 revprob:y probe chip ids in the reverse order. 797 79810.2.17 Fix up PCI configuration space 799 pcifix:<option bits> 800 801 Available option bits: 802 0x0: No attempt to fix PCI configuration space registers values. 803 0x1: Set PCI cache-line size register if not set. 804 0x2: Set write and invalidate bit in PCI command register. 805 0x4: Increase if necessary PCI latency timer according to burst max. 806 807 Use 'pcifix:7' in order to allow the driver to fix up all PCI features. 808 80910.2.18 Serial NVRAM 810 nvram:n do not look for serial NVRAM 811 nvram:y test controllers for onboard serial NVRAM 812 (alternate binary form) 813 mvram=<bits options> 814 0x01 look for NVRAM (equivalent to nvram=y) 815 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices 816 0x04 ignore NVRAM "Wide negotiation" parameter for all devices 817 0x08 ignore NVRAM "Scan at boot time" parameter for all devices 818 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only) 819 82010.2.19 Check SCSI BUS 821 buschk:<option bits> 822 823 Available option bits: 824 0x0: No check. 825 0x1: Check and do not attach the controller on error. 826 0x2: Check and just warn on error. 827 0x4: Disable SCSI bus integrity checking. 828 82910.2.20 Exclude a host from being attached 830 excl=<io_address> 831 832 Prevent host at a given io address from being attached. 833 For example 'ncr53c8xx=excl:0xb400,excl:0xc000' indicate to the 834 ncr53c8xx driver not to attach hosts at address 0xb400 and 0xc000. 835 83610.2.21 Suggest a default SCSI id for hosts 837 hostid:255 no id suggested. 838 hostid:#x (0 < x < 7) x suggested for hosts SCSI id. 839 840 If a host SCSI id is available from the NVRAM, the driver will ignore 841 any value suggested as boot option. Otherwise, if a suggested value 842 different from 255 has been supplied, it will use it. Otherwise, it will 843 try to deduce the value previously set in the hardware and use value 844 7 if the hardware value is zero. 845 84610.2.22 Enable use of IMMEDIATE ARBITRATION 847 (only supported by the sym53c8xx driver. See 10.7 for more details) 848 iarb:0 do not use this feature. 849 iarb:#x use this feature according to bit fields as follow: 850 851 bit 0 (1) : enable IARB each time the initiator has been reselected 852 when it arbitrated for the SCSI BUS. 853 (#x >> 4) : maximum number of successive settings of IARB if the initiator 854 win arbitration and it has other commands to send to a device. 855 856Boot fail safe 857 safe:y load the following assumed fail safe initial setup 858 859 master parity disabled mpar:n 860 scsi parity enabled spar:y 861 disconnections not allowed disc:n 862 special features disabled specf:n 863 ultra scsi disabled ultra:n 864 force sync negotiation disabled fsn:n 865 reverse probe disabled revprob:n 866 PCI fix up disabled pcifix:0 867 serial NVRAM enabled nvram:y 868 verbosity level 2 verb:2 869 tagged command queuing disabled tags:0 870 synchronous negotiation disabled sync:255 871 debug flags none debug:0 872 burst length from BIOS settings burst:255 873 LED support disabled led:0 874 wide support disabled wide:0 875 settle time 10 seconds settle:10 876 differential support from BIOS settings diff:1 877 irq mode from BIOS settings irqm:1 878 SCSI BUS check do not attach on error buschk:1 879 immediate arbitration disabled iarb:0 880 88110.3 Advised boot setup commands 882 883If the driver has been configured with default options, the equivalent 884boot setup is: 885 886 ncr53c8xx=mpar:y,spar:y,disc:y,specf:3,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\ 887 tags:0,sync:50,debug:0,burst:7,led:0,wide:1,settle:2,diff:0,irqm:0 888 889For an installation diskette or a safe but not fast system, 890boot setup can be: 891 892 ncr53c8xx=safe:y,mpar:y,disc:y 893 ncr53c8xx=safe:y,disc:y 894 ncr53c8xx=safe:y,mpar:y 895 ncr53c8xx=safe:y 896 897My personal system works flawlessly with the following equivalent setup: 898 899 ncr53c8xx=mpar:y,spar:y,disc:y,specf:1,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\ 900 tags:32,sync:12,debug:0,burst:7,led:1,wide:1,settle:2,diff:0,irqm:0 901 902The driver prints its actual setup when verbosity level is 2. You can try 903"ncr53c8xx=verb:2" to get the "static" setup of the driver, or add "verb:2" 904to your boot setup command in order to check the actual setup the driver is 905using. 906 90710.4 PCI configuration fix-up boot option 908 909pcifix:<option bits> 910 911Available option bits: 912 0x1: Set PCI cache-line size register if not set. 913 0x2: Set write and invalidate bit in PCI command register. 914 915Use 'pcifix:3' in order to allow the driver to fix both PCI features. 916 917These options only apply to new SYMBIOS chips 810A, 825A, 860, 875 918and 895 and are only supported for Pentium and 486 class processors. 919Recent SYMBIOS 53C8XX scsi processors are able to use PCI read multiple 920and PCI write and invalidate commands. These features require the 921cache line size register to be properly set in the PCI configuration 922space of the chips. On the other hand, chips will use PCI write and 923invalidate commands only if the corresponding bit is set to 1 in the 924PCI command register. 925 926Not all PCI bioses set the PCI cache line register and the PCI write and 927invalidate bit in the PCI configuration space of 53C8XX chips. 928Optimized PCI accesses may be broken for some PCI/memory controllers or 929make problems with some PCI boards. 930 931This fix-up worked flawlessly on my previous system. 932(MB Triton HX / 53C875 / 53C810A) 933I use these options at my own risks as you will do if you decide to 934use them too. 935 936 93710.5 Serial NVRAM support boot option 938 939nvram:n do not look for serial NVRAM 940nvram:y test controllers for onboard serial NVRAM 941 942This option can also been entered as an hexadecimal value that allows 943to control what information the driver will get from the NVRAM and what 944information it will ignore. 945For details see '17. Serial NVRAM support'. 946 947When this option is enabled, the driver tries to detect all boards using 948a Serial NVRAM. This memory is used to hold user set up parameters. 949 950The parameters the driver is able to get from the NVRAM depend on the 951data format used, as follow: 952 953 Tekram format Symbios format 954General and host parameters 955 Boot order N Y 956 Host SCSI ID Y Y 957 SCSI parity checking Y Y 958 Verbose boot messages N Y 959SCSI devices parameters 960 Synchronous transfer speed Y Y 961 Wide 16 / Narrow Y Y 962 Tagged Command Queuing enabled Y Y 963 Disconnections enabled Y Y 964 Scan at boot time N Y 965 966In order to speed up the system boot, for each device configured without 967the "scan at boot time" option, the driver forces an error on the 968first TEST UNIT READY command received for this device. 969 970Some SDMS BIOS revisions seem to be unable to boot cleanly with very fast 971hard disks. In such a situation you cannot configure the NVRAM with 972optimized parameters value. 973 974The 'nvram' boot option can be entered in hexadecimal form in order 975to ignore some options configured in the NVRAM, as follow: 976 977mvram=<bits options> 978 0x01 look for NVRAM (equivalent to nvram=y) 979 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices 980 0x04 ignore NVRAM "Wide negotiation" parameter for all devices 981 0x08 ignore NVRAM "Scan at boot time" parameter for all devices 982 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only) 983 984Option 0x80 is only supported by the sym53c8xx driver and is disabled by 985default. Result is that, by default (option not set), the sym53c8xx driver 986will not attach controllers set to OFF in the NVRAM. 987 988The ncr53c8xx always tries to attach all the controllers. Option 0x80 has 989not been added to the ncr53c8xx driver, since it has been reported to 990confuse users who use this driver since a long time. If you desire a 991controller not to be attached by the ncr53c8xx driver at Linux boot, you 992must use the 'excl' driver boot option. 993 99410.6 SCSI BUS checking boot option. 995 996When this option is set to a non-zero value, the driver checks SCSI lines 997logic state, 100 micro-seconds after having asserted the SCSI RESET line. 998The driver just reads SCSI lines and checks all lines read FALSE except RESET. 999Since SCSI devices shall release the BUS at most 800 nano-seconds after SCSI 1000RESET has been asserted, any signal to TRUE may indicate a SCSI BUS problem. 1001Unfortunately, the following common SCSI BUS problems are not detected: 1002- Only 1 terminator installed. 1003- Misplaced terminators. 1004- Bad quality terminators. 1005On the other hand, either bad cabling, broken devices, not conformant 1006devices, ... may cause a SCSI signal to be wrong when te driver reads it. 1007 100810.7 IMMEDIATE ARBITRATION boot option 1009 1010This option is only supported by the SYM53C8XX driver (not by the NCR53C8XX). 1011 1012SYMBIOS 53C8XX chips are able to arbitrate for the SCSI BUS as soon as they 1013have detected an expected disconnection (BUS FREE PHASE). For this process 1014to be started, bit 1 of SCNTL1 IO register must be set when the chip is 1015connected to the SCSI BUS. 1016 1017When this feature has been enabled for the current connection, the chip has 1018every chance to win arbitration if only devices with lower priority are 1019competing for the SCSI BUS. By the way, when the chip is using SCSI id 7, 1020then it will for sure win the next SCSI BUS arbitration. 1021 1022Since, there is no way to know what devices are trying to arbitrate for the 1023BUS, using this feature can be extremely unfair. So, you are not advised 1024to enable it, or at most enable this feature for the case the chip lost 1025the previous arbitration (boot option 'iarb:1'). 1026 1027This feature has the following advantages: 1028 1029a) Allow the initiator with ID 7 to win arbitration when it wants so. 1030b) Overlap at least 4 micro-seconds of arbitration time with the execution 1031 of SCRIPTS that deal with the end of the current connection and that 1032 starts the next job. 1033 1034Hmmm... But (a) may just prevent other devices from reselecting the initiator, 1035and delay data transfers or status/completions, and (b) may just waste 1036SCSI BUS bandwidth if the SCRIPTS execution lasts more than 4 micro-seconds. 1037 1038The use of IARB needs the SCSI_NCR_IARB_SUPPORT option to have been defined 1039at compile time and the 'iarb' boot option to have been set to a non zero 1040value at boot time. It is not that useful for real work, but can be used 1041to stress SCSI devices or for some applications that can gain advantage of 1042it. By the way, if you experience badnesses like 'unexpected disconnections', 1043'bad reselections', etc... when using IARB on heavy IO load, you should not 1044be surprised, because force-feeding anything and blocking its arse at the 1045same time cannot work for a long time. :-)) 1046 1047 104811. Some constants and flags of the ncr53c8xx.h header file 1049 1050Some of these are defined from the configuration parameters. To 1051change other "defines", you must edit the header file. Do that only 1052if you know what you are doing. 1053 1054SCSI_NCR_SETUP_SPECIAL_FEATURES (default: defined) 1055 If defined, the driver will enable some special features according 1056 to chip and revision id. 1057 For 810A, 860, 825A, 875 and 895 scsi chips, this option enables 1058 support of features that reduce load of PCI bus and memory accesses 1059 during scsi transfer processing: burst op-code fetch, read multiple, 1060 read line, prefetch, cache line, write and invalidate, 1061 burst 128 (875 only), large dma fifo (875 only), offset 16 (875 only). 1062 Can be changed by the following boot setup command: 1063 ncr53c8xx=specf:n 1064 1065SCSI_NCR_IOMAPPED (default: not defined) 1066 If defined, normal I/O is forced. 1067 1068SCSI_NCR_SHARE_IRQ (default: defined) 1069 If defined, request shared IRQ. 1070 1071SCSI_NCR_MAX_TAGS (default: 8) 1072 Maximum number of simultaneous tagged commands to a device. 1073 Can be changed by "settags <target> <maxtags>" 1074 1075SCSI_NCR_SETUP_DEFAULT_SYNC (default: 50) 1076 Transfer period factor the driver will use at boot time for synchronous 1077 negotiation. 0 means asynchronous. 1078 Can be changed by "setsync <target> <period factor>" 1079 1080SCSI_NCR_SETUP_DEFAULT_TAGS (default: 8) 1081 Default number of simultaneous tagged commands to a device. 1082 < 1 means tagged command queuing disabled at start-up. 1083 1084SCSI_NCR_ALWAYS_SIMPLE_TAG (default: defined) 1085 Use SIMPLE TAG for read and write commands. 1086 Can be changed by "setorder <ordered|simple|default>" 1087 1088SCSI_NCR_SETUP_DISCONNECTION (default: defined) 1089 If defined, targets are allowed to disconnect. 1090 1091SCSI_NCR_SETUP_FORCE_SYNC_NEGO (default: not defined) 1092 If defined, synchronous negotiation is tried for all SCSI-2 devices. 1093 Can be changed by "setsync <target> <period>" 1094 1095SCSI_NCR_SETUP_MASTER_PARITY (default: defined) 1096 If defined, master parity checking is enabled. 1097 1098SCSI_NCR_SETUP_MASTER_PARITY (default: defined) 1099 If defined, SCSI parity checking is enabled. 1100 1101SCSI_NCR_PROFILE_SUPPORT (default: not defined) 1102 If defined, profiling information is gathered. 1103 1104SCSI_NCR_MAX_SCATTER (default: 128) 1105 Scatter list size of the driver ccb. 1106 1107SCSI_NCR_MAX_TARGET (default: 16) 1108 Max number of targets per host. 1109 1110SCSI_NCR_MAX_HOST (default: 2) 1111 Max number of host controllers. 1112 1113SCSI_NCR_SETTLE_TIME (default: 2) 1114 Number of seconds the driver will wait after reset. 1115 1116SCSI_NCR_TIMEOUT_ALERT (default: 3) 1117 If a pending command will time out after this amount of seconds, 1118 an ordered tag is used for the next command. 1119 Avoids timeouts for unordered tagged commands. 1120 1121SCSI_NCR_CAN_QUEUE (default: 7*SCSI_NCR_MAX_TAGS) 1122 Max number of commands that can be queued to a host. 1123 1124SCSI_NCR_CMD_PER_LUN (default: SCSI_NCR_MAX_TAGS) 1125 Max number of commands queued to a host for a device. 1126 1127SCSI_NCR_SG_TABLESIZE (default: SCSI_NCR_MAX_SCATTER-1) 1128 Max size of the Linux scatter/gather list. 1129 1130SCSI_NCR_MAX_LUN (default: 8) 1131 Max number of LUNs per target. 1132 1133 113412. Installation 1135 1136This driver is part of the linux kernel distribution. 1137Driver files are located in the sub-directory "drivers/scsi" of the 1138kernel source tree. 1139 1140Driver files: 1141 1142 README.ncr53c8xx : this file 1143 ChangeLog.ncr53c8xx : change log 1144 ncr53c8xx.h : definitions 1145 ncr53c8xx.c : the driver code 1146 1147New driver versions are made available separately in order to allow testing 1148changes and new features prior to including them into the linux kernel 1149distribution. The following URL provides information on latest available 1150patches: 1151 1152 ftp://ftp.tux.org/pub/people/gerard-roudier/README 1153 1154 115513. Architecture dependent features. 1156 1157<Not yet written> 1158 1159 116014. Known problems 1161 116214.1 Tagged commands with Iomega Jaz device 1163 1164I have not tried this device, however it has been reported to me the 1165following: This device is capable of Tagged command queuing. However 1166while spinning up, it rejects Tagged commands. This behaviour is 1167conforms to 6.8.2 of SCSI-2 specifications. The current behaviour of 1168the driver in that situation is not satisfying. So do not enable 1169Tagged command queuing for devices that are able to spin down. The 1170other problem that may appear is timeouts. The only way to avoid 1171timeouts seems to edit linux/drivers/scsi/sd.c and to increase the 1172current timeout values. 1173 117414.2 Device names change when another controller is added. 1175 1176When you add a new NCR53C8XX chip based controller to a system that already 1177has one or more controllers of this family, it may happen that the order 1178the driver registers them to the kernel causes problems due to device 1179name changes. 1180When at least one controller uses NvRAM, SDMS BIOS version 4 allows you to 1181define the order the BIOS will scan the scsi boards. The driver attaches 1182controllers according to BIOS information if NvRAM detect option is set. 1183 1184If your controllers do not have NvRAM, you can: 1185 1186- Ask the driver to probe chip ids in reverse order from the boot command 1187 line: ncr53c8xx=revprob:y 1188- Make appropriate changes in the fstab. 1189- Use the 'scsidev' tool from Eric Youngdale. 1190 119114.3 Using only 8 bit devices with a WIDE SCSI controller. 1192 1193When only 8 bit NARROW devices are connected to a 16 bit WIDE SCSI controller, 1194you must ensure that lines of the wide part of the SCSI BUS are pulled-up. 1195This can be achieved by ENABLING the WIDE TERMINATOR portion of the SCSI 1196controller card. 1197The TYAN 1365 documentation revision 1.2 is not correct about such settings. 1198(page 10, figure 3.3). 1199 120014.4 Possible data corruption during a Memory Write and Invalidate 1201 1202This problem is described in SYMBIOS DEL 397, Part Number 69-039241, ITEM 4. 1203 1204In some complex situations, 53C875 chips revision <= 3 may start a PCI 1205Write and Invalidate Command at a not cache-line-aligned 4 DWORDS boundary. 1206This is only possible when Cache Line Size is 8 DWORDS or greater. 1207Pentium systems use a 8 DWORDS cache line size and so are concerned by 1208this chip bug, unlike i486 systems that use a 4 DWORDS cache line size. 1209 1210When this situation occurs, the chip may complete the Write and Invalidate 1211command after having only filled part of the last cache line involved in 1212the transfer, leaving to data corruption the remainder of this cache line. 1213 1214Not using Write And Invalidate obviously gets rid of this chip bug, and so 1215it is now the default setting of the driver. 1216However, for people like me who want to enable this feature, I have added 1217part of a work-around suggested by SYMBIOS. This work-around resets the 1218addressing logic when the DATA IN phase is entered and so prevents the bug 1219from being triggered for the first SCSI MOVE of the phase. This work-around 1220should be enough according to the following: 1221 1222The only driver internal data structure that is greater than 8 DWORDS and 1223that is moved by the SCRIPTS processor is the 'CCB header' that contains 1224the context of the SCSI transfer. This data structure is aligned on 8 DWORDS 1225boundary (Pentium Cache Line Size), and so is immune to this chip bug, at 1226least on Pentium systems. 1227But the conditions of this bug can be met when a SCSI read command is 1228performed using a buffer that is 4 DWORDS but not cache-line aligned. 1229This cannot happen under Linux when scatter/gather lists are used since 1230they only refer to system buffers that are well aligned. So, a work around 1231may only be needed under Linux when a scatter/gather list is not used and 1232when the SCSI DATA IN phase is reentered after a phase mismatch. 1233 123414.5 IRQ sharing problems 1235 1236When an IRQ is shared by devices that are handled by different drivers, it 1237may happen that one driver complains about the request of the IRQ having 1238failed. Inder Linux-2.0, this may be due to one driver having requested the 1239IRQ using the IRQF_DISABLED flag but some other having requested the same IRQ 1240without this flag. Under both Linux-2.0 and linux-2.2, this may be caused by 1241one driver not having requested the IRQ with the IRQF_SHARED flag. 1242 1243By default, the ncr53c8xx and sym53c8xx drivers request IRQs with both the 1244IRQF_DISABLED and the IRQF_SHARED flag under Linux-2.0 and with only the IRQF_SHARED 1245flag under Linux-2.2. 1246 1247Under Linux-2.0, you can disable use of IRQF_DISABLED flag from the boot 1248command line by using the following option: 1249 1250 ncr53c8xx=irqm:0x20 (for the generic ncr53c8xx driver) 1251 sym53c8xx=irqm:0x20 (for the sym53c8xx driver) 1252 1253If this does not fix the problem, then you may want to check how all other 1254drivers are requesting the IRQ and report the problem. Note that if at least 1255a single driver does not request the IRQ with the IRQF_SHARED flag (share IRQ), 1256then the request of the IRQ obviously will not succeed for all the drivers. 1257 125815. SCSI problem troubleshooting 1259 126015.1 Problem tracking 1261 1262Most SCSI problems are due to a non conformant SCSI bus or to buggy 1263devices. If unfortunately you have SCSI problems, you can check the 1264following things: 1265 1266- SCSI bus cables 1267- terminations at both end of the SCSI chain 1268- linux syslog messages (some of them may help you) 1269 1270If you do not find the source of problems, you can configure the 1271driver with no features enabled. 1272 1273- only asynchronous data transfers 1274- tagged commands disabled 1275- disconnections not allowed 1276 1277Now, if your SCSI bus is ok, your system have every chance to work 1278with this safe configuration but performances will not be optimal. 1279 1280If it still fails, then you can send your problem description to 1281appropriate mailing lists or news-groups. Send me a copy in order to 1282be sure I will receive it. Obviously, a bug in the driver code is 1283possible. 1284 1285 My email address: Gerard Roudier <groudier@free.fr> 1286 1287Allowing disconnections is important if you use several devices on 1288your SCSI bus but often causes problems with buggy devices. 1289Synchronous data transfers increases throughput of fast devices like 1290hard disks. Good SCSI hard disks with a large cache gain advantage of 1291tagged commands queuing. 1292 1293Try to enable one feature at a time with control commands. For example: 1294 1295- echo "setsync all 25" >/proc/scsi/ncr53c8xx/0 1296 Will enable fast synchronous data transfer negotiation for all targets. 1297 1298- echo "setflag 3" >/proc/scsi/ncr53c8xx/0 1299 Will reset flags (no_disc) for target 3, and so will allow it to disconnect 1300 the SCSI Bus. 1301 1302- echo "settags 3 8" >/proc/scsi/ncr53c8xx/0 1303 Will enable tagged command queuing for target 3 if that device supports it. 1304 1305Once you have found the device and the feature that cause problems, just 1306disable that feature for that device. 1307 130815.2 Understanding hardware error reports 1309 1310When the driver detects an unexpected error condition, it may display a 1311message of the following pattern. 1312 1313sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000). 1314sym53c876-0: script cmd = 19000000 1315sym53c876-0: regdump: da 10 80 95 47 0f 01 07 75 01 81 21 80 01 09 00. 1316 1317Some fields in such a message may help you understand the cause of the 1318problem, as follows: 1319 1320sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000). 1321............A.........B.C....D.E..F....G.H.......I.....J...K....... 1322 1323Field A : target number. 1324 SCSI ID of the device the controller was talking with at the moment the 1325 error occurs. 1326 1327Field B : DSTAT io register (DMA STATUS) 1328 Bit 0x40 : MDPE Master Data Parity Error 1329 Data parity error detected on the PCI BUS. 1330 Bit 0x20 : BF Bus Fault 1331 PCI bus fault condition detected 1332 Bit 0x01 : IID Illegal Instruction Detected 1333 Set by the chip when it detects an Illegal Instruction format 1334 on some condition that makes an instruction illegal. 1335 Bit 0x80 : DFE Dma Fifo Empty 1336 Pure status bit that does not indicate an error. 1337 If the reported DSTAT value contains a combination of MDPE (0x40), 1338 BF (0x20), then the cause may be likely due to a PCI BUS problem. 1339 1340Field C : SIST io register (SCSI Interrupt Status) 1341 Bit 0x08 : SGE SCSI GROSS ERROR 1342 Indicates that the chip detected a severe error condition 1343 on the SCSI BUS that prevents the SCSI protocol from functioning 1344 properly. 1345 Bit 0x04 : UDC Unexpected Disconnection 1346 Indicates that the device released the SCSI BUS when the chip 1347 was not expecting this to happen. A device may behave so to 1348 indicate the SCSI initiator that an error condition not reportable using the SCSI protocol has occurred. 1349 Bit 0x02 : RST SCSI BUS Reset 1350 Generally SCSI targets do not reset the SCSI BUS, although any 1351 device on the BUS can reset it at any time. 1352 Bit 0x01 : PAR Parity 1353 SCSI parity error detected. 1354 On a faulty SCSI BUS, any error condition among SGE (0x08), UDC (0x04) and 1355 PAR (0x01) may be detected by the chip. If your SCSI system sometimes 1356 encounters such error conditions, especially SCSI GROSS ERROR, then a SCSI 1357 BUS problem is likely the cause of these errors. 1358 1359For fields D,E,F,G and H, you may look into the sym53c8xx_defs.h file 1360that contains some minimal comments on IO register bits. 1361Field D : SOCL Scsi Output Control Latch 1362 This register reflects the state of the SCSI control lines the 1363 chip want to drive or compare against. 1364Field E : SBCL Scsi Bus Control Lines 1365 Actual value of control lines on the SCSI BUS. 1366Field F : SBDL Scsi Bus Data Lines 1367 Actual value of data lines on the SCSI BUS. 1368Field G : SXFER SCSI Transfer 1369 Contains the setting of the Synchronous Period for output and 1370 the current Synchronous offset (offset 0 means asynchronous). 1371Field H : SCNTL3 Scsi Control Register 3 1372 Contains the setting of timing values for both asynchronous and 1373 synchronous data transfers. 1374 1375Understanding Fields I, J, K and dumps requires to have good knowledge of 1376SCSI standards, chip cores functionnals and internal driver data structures. 1377You are not required to decode and understand them, unless you want to help 1378maintain the driver code. 1379 138016. Synchronous transfer negotiation tables 1381 1382Tables below have been created by calling the routine the driver uses 1383for synchronisation negotiation timing calculation and chip setting. 1384The first table corresponds to Ultra chips 53875 and 53C860 with 80 MHz 1385clock and 5 clock divisors. 1386The second one has been calculated by setting the scsi clock to 40 Mhz 1387and using 4 clock divisors and so applies to all NCR53C8XX chips in fast 1388SCSI-2 mode. 1389 1390Periods are in nano-seconds and speeds are in Mega-transfers per second. 13911 Mega-transfers/second means 1 MB/s with 8 bits SCSI and 2 MB/s with 1392Wide16 SCSI. 1393 139416.1 Synchronous timings for 53C895, 53C875 and 53C860 SCSI controllers 1395 1396 ---------------------------------------------- 1397 Negotiated NCR settings 1398 Factor Period Speed Period Speed 1399 ------ ------ ------ ------ ------ 1400 10 25 40.000 25 40.000 (53C895 only) 1401 11 30.2 33.112 31.25 32.000 (53C895 only) 1402 12 50 20.000 50 20.000 1403 13 52 19.230 62 16.000 1404 14 56 17.857 62 16.000 1405 15 60 16.666 62 16.000 1406 16 64 15.625 75 13.333 1407 17 68 14.705 75 13.333 1408 18 72 13.888 75 13.333 1409 19 76 13.157 87 11.428 1410 20 80 12.500 87 11.428 1411 21 84 11.904 87 11.428 1412 22 88 11.363 93 10.666 1413 23 92 10.869 93 10.666 1414 24 96 10.416 100 10.000 1415 25 100 10.000 100 10.000 1416 26 104 9.615 112 8.888 1417 27 108 9.259 112 8.888 1418 28 112 8.928 112 8.888 1419 29 116 8.620 125 8.000 1420 30 120 8.333 125 8.000 1421 31 124 8.064 125 8.000 1422 32 128 7.812 131 7.619 1423 33 132 7.575 150 6.666 1424 34 136 7.352 150 6.666 1425 35 140 7.142 150 6.666 1426 36 144 6.944 150 6.666 1427 37 148 6.756 150 6.666 1428 38 152 6.578 175 5.714 1429 39 156 6.410 175 5.714 1430 40 160 6.250 175 5.714 1431 41 164 6.097 175 5.714 1432 42 168 5.952 175 5.714 1433 43 172 5.813 175 5.714 1434 44 176 5.681 187 5.333 1435 45 180 5.555 187 5.333 1436 46 184 5.434 187 5.333 1437 47 188 5.319 200 5.000 1438 48 192 5.208 200 5.000 1439 49 196 5.102 200 5.000 1440 1441 144216.2 Synchronous timings for fast SCSI-2 53C8XX controllers 1443 1444 ---------------------------------------------- 1445 Negotiated NCR settings 1446 Factor Period Speed Period Speed 1447 ------ ------ ------ ------ ------ 1448 25 100 10.000 100 10.000 1449 26 104 9.615 125 8.000 1450 27 108 9.259 125 8.000 1451 28 112 8.928 125 8.000 1452 29 116 8.620 125 8.000 1453 30 120 8.333 125 8.000 1454 31 124 8.064 125 8.000 1455 32 128 7.812 131 7.619 1456 33 132 7.575 150 6.666 1457 34 136 7.352 150 6.666 1458 35 140 7.142 150 6.666 1459 36 144 6.944 150 6.666 1460 37 148 6.756 150 6.666 1461 38 152 6.578 175 5.714 1462 39 156 6.410 175 5.714 1463 40 160 6.250 175 5.714 1464 41 164 6.097 175 5.714 1465 42 168 5.952 175 5.714 1466 43 172 5.813 175 5.714 1467 44 176 5.681 187 5.333 1468 45 180 5.555 187 5.333 1469 46 184 5.434 187 5.333 1470 47 188 5.319 200 5.000 1471 48 192 5.208 200 5.000 1472 49 196 5.102 200 5.000 1473 1474 147517. Serial NVRAM (added by Richard Waltham: dormouse@farsrobt.demon.co.uk) 1476 147717.1 Features 1478 1479Enabling serial NVRAM support enables detection of the serial NVRAM included 1480on Symbios and some Symbios compatible host adaptors, and Tekram boards. The 1481serial NVRAM is used by Symbios and Tekram to hold set up parameters for the 1482host adaptor and it's attached drives. 1483 1484The Symbios NVRAM also holds data on the boot order of host adaptors in a 1485system with more than one host adaptor. This enables the order of scanning 1486the cards for drives to be changed from the default used during host adaptor 1487detection. 1488 1489This can be done to a limited extent at the moment using "reverse probe" but 1490this only changes the order of detection of different types of cards. The 1491NVRAM boot order settings can do this as well as change the order the same 1492types of cards are scanned in, something "reverse probe" cannot do. 1493 1494Tekram boards using Symbios chips, DC390W/F/U, which have NVRAM are detected 1495and this is used to distinguish between Symbios compatible and Tekram host 1496adaptors. This is used to disable the Symbios compatible "diff" setting 1497incorrectly set on Tekram boards if the CONFIG_SCSI_53C8XX_SYMBIOS_COMPAT 1498configuration parameter is set enabling both Symbios and Tekram boards to be 1499used together with the Symbios cards using all their features, including 1500"diff" support. ("led pin" support for Symbios compatible cards can remain 1501enabled when using Tekram cards. It does nothing useful for Tekram host 1502adaptors but does not cause problems either.) 1503 1504 150517.2 Symbios NVRAM layout 1506 1507typical data at NVRAM address 0x100 (53c810a NVRAM) 1508----------------------------------------------------------- 150900 00 151064 01 15118e 0b 1512 151300 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00 1514 151504 00 0f 00 00 10 00 50 00 00 01 00 00 62 151604 00 03 00 00 10 00 58 00 00 01 00 00 63 151704 00 01 00 00 10 00 48 00 00 01 00 00 61 151800 00 00 00 00 00 00 00 00 00 00 00 00 00 1519 15200f 00 08 08 64 00 0a 00 15210f 00 08 08 64 00 0a 00 15220f 00 08 08 64 00 0a 00 15230f 00 08 08 64 00 0a 00 15240f 00 08 08 64 00 0a 00 15250f 00 08 08 64 00 0a 00 15260f 00 08 08 64 00 0a 00 15270f 00 08 08 64 00 0a 00 1528 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 15330f 00 08 08 64 00 0a 00 15340f 00 08 08 64 00 0a 00 15350f 00 08 08 64 00 0a 00 15360f 00 08 08 64 00 0a 00 1537 153800 00 00 00 00 00 00 00 153900 00 00 00 00 00 00 00 154000 00 00 00 00 00 00 00 154100 00 00 00 00 00 00 00 154200 00 00 00 00 00 00 00 154300 00 00 00 00 00 00 00 154400 00 00 00 00 00 00 00 154500 00 00 00 00 00 00 00 1546 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 155100 00 00 00 00 00 00 00 155200 00 00 00 00 00 00 00 155300 00 00 00 00 00 00 00 155400 00 00 00 00 00 00 00 1555 155600 00 00 00 00 00 00 00 155700 00 00 00 00 00 00 00 155800 00 00 00 00 00 00 00 1559 1560fe fe 156100 00 156200 00 1563----------------------------------------------------------- 1564NVRAM layout details 1565 1566NVRAM Address 0x000-0x0ff not used 1567 0x100-0x26f initialised data 1568 0x270-0x7ff not used 1569 1570general layout 1571 1572 header - 6 bytes, 1573 data - 356 bytes (checksum is byte sum of this data) 1574 trailer - 6 bytes 1575 --- 1576 total 368 bytes 1577 1578data area layout 1579 1580 controller set up - 20 bytes 1581 boot configuration - 56 bytes (4x14 bytes) 1582 device set up - 128 bytes (16x8 bytes) 1583 unused (spare?) - 152 bytes (19x8 bytes) 1584 --- 1585 total 356 bytes 1586 1587----------------------------------------------------------- 1588header 1589 159000 00 - ?? start marker 159164 01 - byte count (lsb/msb excludes header/trailer) 15928e 0b - checksum (lsb/msb excludes header/trailer) 1593----------------------------------------------------------- 1594controller set up 1595 159600 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00 1597 | | | | 1598 | | | -- host ID 1599 | | | 1600 | | --Removable Media Support 1601 | | 0x00 = none 1602 | | 0x01 = Bootable Device 1603 | | 0x02 = All with Media 1604 | | 1605 | --flag bits 2 1606 | 0x00000001= scan order hi->low 1607 | (default 0x00 - scan low->hi) 1608 --flag bits 1 1609 0x00000001 scam enable 1610 0x00000010 parity enable 1611 0x00000100 verbose boot msgs 1612 1613remaining bytes unknown - they do not appear to change in my 1614current set up for any of the controllers. 1615 1616default set up is identical for 53c810a and 53c875 NVRAM 1617(Removable Media added Symbios BIOS version 4.09) 1618----------------------------------------------------------- 1619boot configuration 1620 1621boot order set by order of the devices in this table 1622 162304 00 0f 00 00 10 00 50 00 00 01 00 00 62 -- 1st controller 162404 00 03 00 00 10 00 58 00 00 01 00 00 63 2nd controller 162504 00 01 00 00 10 00 48 00 00 01 00 00 61 3rd controller 162600 00 00 00 00 00 00 00 00 00 00 00 00 00 4th controller 1627 | | | | | | | | 1628 | | | | | | ---- PCI io port adr 1629 | | | | | --0x01 init/scan at boot time 1630 | | | | --PCI device/function number (0xdddddfff) 1631 | | ----- ?? PCI vendor ID (lsb/msb) 1632 ----PCI device ID (lsb/msb) 1633 1634?? use of this data is a guess but seems reasonable 1635 1636remaining bytes unknown - they do not appear to change in my 1637current set up 1638 1639default set up is identical for 53c810a and 53c875 NVRAM 1640----------------------------------------------------------- 1641device set up (up to 16 devices - includes controller) 1642 16430f 00 08 08 64 00 0a 00 - id 0 16440f 00 08 08 64 00 0a 00 16450f 00 08 08 64 00 0a 00 16460f 00 08 08 64 00 0a 00 16470f 00 08 08 64 00 0a 00 16480f 00 08 08 64 00 0a 00 16490f 00 08 08 64 00 0a 00 16500f 00 08 08 64 00 0a 00 1651 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 16560f 00 08 08 64 00 0a 00 16570f 00 08 08 64 00 0a 00 16580f 00 08 08 64 00 0a 00 16590f 00 08 08 64 00 0a 00 - id 15 1660 | | | | | | 1661 | | | | ----timeout (lsb/msb) 1662 | | | --synch period (0x?? 40 Mtrans/sec- fast 40) (probably 0x28) 1663 | | | (0x30 20 Mtrans/sec- fast 20) 1664 | | | (0x64 10 Mtrans/sec- fast ) 1665 | | | (0xc8 5 Mtrans/sec) 1666 | | | (0x00 asynchronous) 1667 | | -- ?? max sync offset (0x08 in NVRAM on 53c810a) 1668 | | (0x10 in NVRAM on 53c875) 1669 | --device bus width (0x08 narrow) 1670 | (0x10 16 bit wide) 1671 --flag bits 1672 0x00000001 - disconnect enabled 1673 0x00000010 - scan at boot time 1674 0x00000100 - scan luns 1675 0x00001000 - queue tags enabled 1676 1677remaining bytes unknown - they do not appear to change in my 1678current set up 1679 1680?? use of this data is a guess but seems reasonable 1681(but it could be max bus width) 1682 1683default set up for 53c810a NVRAM 1684default set up for 53c875 NVRAM - bus width - 0x10 1685 - sync offset ? - 0x10 1686 - sync period - 0x30 1687----------------------------------------------------------- 1688?? spare device space (32 bit bus ??) 1689 169000 00 00 00 00 00 00 00 (19x8bytes) 1691. 1692. 169300 00 00 00 00 00 00 00 1694 1695default set up is identical for 53c810a and 53c875 NVRAM 1696----------------------------------------------------------- 1697trailer 1698 1699fe fe - ? end marker ? 170000 00 170100 00 1702 1703default set up is identical for 53c810a and 53c875 NVRAM 1704----------------------------------------------------------- 1705 1706 1707 170817.3 Tekram NVRAM layout 1709 1710nvram 64x16 (1024 bit) 1711 1712Drive settings 1713 1714Drive ID 0-15 (addr 0x0yyyy0 = device setup, yyyy = ID) 1715 (addr 0x0yyyy1 = 0x0000) 1716 1717 x x x x x x x x x x x x x x x x 1718 | | | | | | | | | 1719 | | | | | | | | ----- parity check 0 - off 1720 | | | | | | | | 1 - on 1721 | | | | | | | | 1722 | | | | | | | ------- sync neg 0 - off 1723 | | | | | | | 1 - on 1724 | | | | | | | 1725 | | | | | | --------- disconnect 0 - off 1726 | | | | | | 1 - on 1727 | | | | | | 1728 | | | | | ----------- start cmd 0 - off 1729 | | | | | 1 - on 1730 | | | | | 1731 | | | | -------------- tagged cmds 0 - off 1732 | | | | 1 - on 1733 | | | | 1734 | | | ---------------- wide neg 0 - off 1735 | | | 1 - on 1736 | | | 1737 --------------------------- sync rate 0 - 10.0 Mtrans/sec 1738 1 - 8.0 1739 2 - 6.6 1740 3 - 5.7 1741 4 - 5.0 1742 5 - 4.0 1743 6 - 3.0 1744 7 - 2.0 1745 7 - 2.0 1746 8 - 20.0 1747 9 - 16.7 1748 a - 13.9 1749 b - 11.9 1750 1751Global settings 1752 1753Host flags 0 (addr 0x100000, 32) 1754 1755 x x x x x x x x x x x x x x x x 1756 | | | | | | | | | | | | 1757 | | | | | | | | ----------- host ID 0x00 - 0x0f 1758 | | | | | | | | 1759 | | | | | | | ----------------------- support for 0 - off 1760 | | | | | | | > 2 drives 1 - on 1761 | | | | | | | 1762 | | | | | | ------------------------- support drives 0 - off 1763 | | | | | | > 1Gbytes 1 - on 1764 | | | | | | 1765 | | | | | --------------------------- bus reset on 0 - off 1766 | | | | | power on 1 - on 1767 | | | | | 1768 | | | | ----------------------------- active neg 0 - off 1769 | | | | 1 - on 1770 | | | | 1771 | | | -------------------------------- imm seek 0 - off 1772 | | | 1 - on 1773 | | | 1774 | | ---------------------------------- scan luns 0 - off 1775 | | 1 - on 1776 | | 1777 -------------------------------------- removable 0 - disable 1778 as BIOS dev 1 - boot device 1779 2 - all 1780 1781Host flags 1 (addr 0x100001, 33) 1782 1783 x x x x x x x x x x x x x x x x 1784 | | | | | | 1785 | | | --------- boot delay 0 - 3 sec 1786 | | | 1 - 5 1787 | | | 2 - 10 1788 | | | 3 - 20 1789 | | | 4 - 30 1790 | | | 5 - 60 1791 | | | 6 - 120 1792 | | | 1793 --------------------------- max tag cmds 0 - 2 1794 1 - 4 1795 2 - 8 1796 3 - 16 1797 4 - 32 1798 1799Host flags 2 (addr 0x100010, 34) 1800 1801 x x x x x x x x x x x x x x x x 1802 | 1803 ----- F2/F6 enable 0 - off ??? 1804 1 - on ??? 1805 1806checksum (addr 0x111111) 1807 1808checksum = 0x1234 - (sum addr 0-63) 1809 1810---------------------------------------------------------------------------- 1811 1812default nvram data: 1813 18140x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 18150x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 18160x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 18170x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 1818 18190x0f07 0x0400 0x0001 0x0000 0x0000 0x0000 0x0000 0x0000 18200x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 18210x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 18220x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0xfbbc 1823 1824 182518. Support for Big Endian 1826 1827The PCI local bus has been primarily designed for x86 architecture. 1828As a consequence, PCI devices generally expect DWORDS using little endian 1829byte ordering. 1830 183118.1 Big Endian CPU 1832 1833In order to support NCR chips on a Big Endian architecture the driver has to 1834perform byte reordering each time it is needed. This feature has been 1835added to the driver by Cort <cort@cs.nmt.edu> and is available in driver 1836version 2.5 and later ones. For the moment Big Endian support has only 1837been tested on Linux/PPC (PowerPC). 1838 183918.2 NCR chip in Big Endian mode of operations 1840 1841It can be read in SYMBIOS documentation that some chips support a special 1842Big Endian mode, on paper: 53C815, 53C825A, 53C875, 53C875N, 53C895. 1843This mode of operations is not software-selectable, but needs pin named 1844BigLit to be pulled-up. Using this mode, most of byte reorderings should 1845be avoided when the driver is running on a Big Endian CPU. 1846Driver version 2.5 is also, in theory, ready for this feature. 1847 1848=============================================================================== 1849End of NCR53C8XX driver README file 1850