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diff --git a/Documentation/scsi/ncr53c8xx.txt b/Documentation/scsi/ncr53c8xx.txt deleted file mode 100644 index 8586efff1e99..000000000000 --- a/Documentation/scsi/ncr53c8xx.txt +++ /dev/null @@ -1,1824 +0,0 @@ -The Linux NCR53C8XX/SYM53C8XX drivers README file - -Written by Gerard Roudier <groudier@free.fr> -21 Rue Carnot -95170 DEUIL LA BARRE - FRANCE - -29 May 1999 -=============================================================================== - -1. Introduction -2. Supported chips and SCSI features -3. Advantages of the enhanced 896 driver - 3.1 Optimized SCSI SCRIPTS - 3.2 New features of the SYM53C896 (64 bit PCI dual LVD SCSI controller) -4. Memory mapped I/O versus normal I/O -5. Tagged command queueing -6. Parity checking -7. Profiling information -8. Control commands - 8.1 Set minimum synchronous period - 8.2 Set wide size - 8.3 Set maximum number of concurrent tagged commands - 8.4 Set order type for tagged command - 8.5 Set debug mode - 8.6 Clear profile counters - 8.7 Set flag (no_disc) - 8.8 Set verbose level - 8.9 Reset all logical units of a target - 8.10 Abort all tasks of all logical units of a target -9. Configuration parameters -10. Boot setup commands - 10.1 Syntax - 10.2 Available arguments - 10.2.1 Master parity checking - 10.2.2 Scsi parity checking - 10.2.3 Scsi disconnections - 10.2.4 Special features - 10.2.5 Ultra SCSI support - 10.2.6 Default number of tagged commands - 10.2.7 Default synchronous period factor - 10.2.8 Negotiate synchronous with all devices - 10.2.9 Verbosity level - 10.2.10 Debug mode - 10.2.11 Burst max - 10.2.12 LED support - 10.2.13 Max wide - 10.2.14 Differential mode - 10.2.15 IRQ mode - 10.2.16 Reverse probe - 10.2.17 Fix up PCI configuration space - 10.2.18 Serial NVRAM - 10.2.19 Check SCSI BUS - 10.2.20 Exclude a host from being attached - 10.2.21 Suggest a default SCSI id for hosts - 10.2.22 Enable use of IMMEDIATE ARBITRATION - 10.3 Advised boot setup commands - 10.4 PCI configuration fix-up boot option - 10.5 Serial NVRAM support boot option - 10.6 SCSI BUS checking boot option - 10.7 IMMEDIATE ARBITRATION boot option -11. Some constants and flags of the ncr53c8xx.h header file -12. Installation -13. Architecture dependent features -14. Known problems - 14.1 Tagged commands with Iomega Jaz device - 14.2 Device names change when another controller is added - 14.3 Using only 8 bit devices with a WIDE SCSI controller. - 14.4 Possible data corruption during a Memory Write and Invalidate - 14.5 IRQ sharing problems -15. SCSI problem troubleshooting - 15.1 Problem tracking - 15.2 Understanding hardware error reports -16. Synchronous transfer negotiation tables - 16.1 Synchronous timings for 53C875 and 53C860 Ultra-SCSI controllers - 16.2 Synchronous timings for fast SCSI-2 53C8XX controllers -17. Serial NVRAM support (by Richard Waltham) - 17.1 Features - 17.2 Symbios NVRAM layout - 17.3 Tekram NVRAM layout -18. Support for Big Endian - 18.1 Big Endian CPU - 18.2 NCR chip in Big Endian mode of operations - -=============================================================================== - -1. Introduction - -The initial Linux ncr53c8xx driver has been a port of the ncr driver from -FreeBSD that has been achieved in November 1995 by: - Gerard Roudier <groudier@free.fr> - -The original driver has been written for 386bsd and FreeBSD by: - Wolfgang Stanglmeier <wolf@cologne.de> - Stefan Esser <se@mi.Uni-Koeln.de> - -It is now available as a bundle of 2 drivers: - -- ncr53c8xx generic driver that supports all the SYM53C8XX family including - the earliest 810 rev. 1, the latest 896 (2 channel LVD SCSI controller) and - the new 895A (1 channel LVD SCSI controller). -- sym53c8xx enhanced driver (a.k.a. 896 drivers) that drops support of oldest - chips in order to gain advantage of new features, as LOAD/STORE instructions - available since the 810A and hardware phase mismatch available with the - 896 and the 895A. - -You can find technical information about the NCR 8xx family in the -PCI-HOWTO written by Michael Will and in the SCSI-HOWTO written by -Drew Eckhardt. - -Information about new chips is available at LSILOGIC web server: - - http://www.lsilogic.com/ - -SCSI standard documentations are available at SYMBIOS ftp server: - - ftp://ftp.symbios.com/ - -Useful SCSI tools written by Eric Youngdale are available at tsx-11: - - ftp://tsx-11.mit.edu/pub/linux/ALPHA/scsi/scsiinfo-X.Y.tar.gz - ftp://tsx-11.mit.edu/pub/linux/ALPHA/scsi/scsidev-X.Y.tar.gz - -These tools are not ALPHA but quite clean and work quite well. -It is essential you have the 'scsiinfo' package. - -This short documentation describes the features of the generic and enhanced -drivers, configuration parameters and control commands available through -the proc SCSI file system read / write operations. - -This driver has been tested OK with linux/i386, Linux/Alpha and Linux/PPC. - -Latest driver version and patches are available at: - - ftp://ftp.tux.org/pub/people/gerard-roudier -or - ftp://ftp.symbios.com/mirror/ftp.tux.org/pub/tux/roudier/drivers - -I am not a native speaker of English and there are probably lots of -mistakes in this README file. Any help will be welcome. - - -2. Supported chips and SCSI features - -The following features are supported for all chips: - - Synchronous negotiation - Disconnection - Tagged command queuing - SCSI parity checking - Master parity checking - -"Wide negotiation" is supported for chips that allow it. The -following table shows some characteristics of NCR 8xx family chips -and what drivers support them. - - Supported by Supported by - On board the generic the enhanced -Chip SDMS BIOS Wide SCSI std. Max. sync driver driver ----- --------- ---- --------- ---------- ------------ ------------- -810 N N FAST10 10 MB/s Y N -810A N N FAST10 10 MB/s Y Y -815 Y N FAST10 10 MB/s Y N -825 Y Y FAST10 20 MB/s Y N -825A Y Y FAST10 20 MB/s Y Y -860 N N FAST20 20 MB/s Y Y -875 Y Y FAST20 40 MB/s Y Y -876 Y Y FAST20 40 MB/s Y Y -895 Y Y FAST40 80 MB/s Y Y -895A Y Y FAST40 80 MB/s Y Y -896 Y Y FAST40 80 MB/s Y Y -897 Y Y FAST40 80 MB/s Y Y -1510D Y Y FAST40 80 MB/s Y Y -1010 Y Y FAST80 160 MB/s N Y -1010_66* Y Y FAST80 160 MB/s N Y - -* Chip supports 33MHz and 66MHz PCI buses. - - -Summary of other supported features: - -Module: allow to load the driver -Memory mapped I/O: increases performance -Profiling information: read operations from the proc SCSI file system -Control commands: write operations to the proc SCSI file system -Debugging information: written to syslog (expert only) -Scatter / gather -Shared interrupt -Boot setup commands -Serial NVRAM: Symbios and Tekram formats - - -3. Advantages of the enhanced 896 driver - -3.1 Optimized SCSI SCRIPTS. - -The 810A, 825A, 875, 895, 896 and 895A support new SCSI SCRIPTS instructions -named LOAD and STORE that allow to move up to 1 DWORD from/to an IO register -to/from memory much faster that the MOVE MEMORY instruction that is supported -by the 53c7xx and 53c8xx family. -The LOAD/STORE instructions support absolute and DSA relative addressing -modes. The SCSI SCRIPTS had been entirely rewritten using LOAD/STORE instead -of MOVE MEMORY instructions. - -3.2 New features of the SYM53C896 (64 bit PCI dual LVD SCSI controller) - -The 896 and the 895A allows handling of the phase mismatch context from -SCRIPTS (avoids the phase mismatch interrupt that stops the SCSI processor -until the C code has saved the context of the transfer). -Implementing this without using LOAD/STORE instructions would be painful -and I didn't even want to try it. - -The 896 chip supports 64 bit PCI transactions and addressing, while the -895A supports 32 bit PCI transactions and 64 bit addressing. -The SCRIPTS processor of these chips is not true 64 bit, but uses segment -registers for bit 32-63. Another interesting feature is that LOAD/STORE -instructions that address the on-chip RAM (8k) remain internal to the chip. - -Due to the use of LOAD/STORE SCRIPTS instructions, this driver does not -support the following chips: -- SYM53C810 revision < 0x10 (16) -- SYM53C815 all revisions -- SYM53C825 revision < 0x10 (16) - -4. Memory mapped I/O versus normal I/O - -Memory mapped I/O has less latency than normal I/O. Since -linux-1.3.x, memory mapped I/O is used rather than normal I/O. Memory -mapped I/O seems to work fine on most hardware configurations, but -some poorly designed motherboards may break this feature. - -The configuration option CONFIG_SCSI_NCR53C8XX_IOMAPPED forces the -driver to use normal I/O in all cases. - - -5. Tagged command queueing - -Queuing more than 1 command at a time to a device allows it to perform -optimizations based on actual head positions and its mechanical -characteristics. This feature may also reduce average command latency. -In order to really gain advantage of this feature, devices must have -a reasonable cache size (No miracle is to be expected for a low-end -hard disk with 128 KB or less). -Some known SCSI devices do not properly support tagged command queuing. -Generally, firmware revisions that fix this kind of problems are available -at respective vendor web/ftp sites. -All I can say is that the hard disks I use on my machines behave well with -this driver with tagged command queuing enabled: - -- IBM S12 0662 -- Conner 1080S -- Quantum Atlas I -- Quantum Atlas II - -If your controller has NVRAM, you can configure this feature per target -from the user setup tool. The Tekram Setup program allows to tune the -maximum number of queued commands up to 32. The Symbios Setup only allows -to enable or disable this feature. - -The maximum number of simultaneous tagged commands queued to a device -is currently set to 8 by default. This value is suitable for most SCSI -disks. With large SCSI disks (>= 2GB, cache >= 512KB, average seek time -<= 10 ms), using a larger value may give better performances. - -The sym53c8xx driver supports up to 255 commands per device, and the -generic ncr53c8xx driver supports up to 64, but using more than 32 is -generally not worth-while, unless you are using a very large disk or disk -array. It is noticeable that most of recent hard disks seem not to accept -more than 64 simultaneous commands. So, using more than 64 queued commands -is probably just resource wasting. - -If your controller does not have NVRAM or if it is managed by the SDMS -BIOS/SETUP, you can configure tagged queueing feature and device queue -depths from the boot command-line. For example: - - ncr53c8xx=tags:4/t2t3q15-t4q7/t1u0q32 - -will set tagged commands queue depths as follow: - -- target 2 all luns on controller 0 --> 15 -- target 3 all luns on controller 0 --> 15 -- target 4 all luns on controller 0 --> 7 -- target 1 lun 0 on controller 1 --> 32 -- all other target/lun --> 4 - -In some special conditions, some SCSI disk firmwares may return a -QUEUE FULL status for a SCSI command. This behaviour is managed by the -driver using the following heuristic: - -- Each time a QUEUE FULL status is returned, tagged queue depth is reduced - to the actual number of disconnected commands. - -- Every 1000 successfully completed SCSI commands, if allowed by the - current limit, the maximum number of queueable commands is incremented. - -Since QUEUE FULL status reception and handling is resource wasting, the -driver notifies by default this problem to user by indicating the actual -number of commands used and their status, as well as its decision on the -device queue depth change. -The heuristic used by the driver in handling QUEUE FULL ensures that the -impact on performances is not too bad. You can get rid of the messages by -setting verbose level to zero, as follow: - -1st method: boot your system using 'ncr53c8xx=verb:0' option. -2nd method: apply "setverbose 0" control command to the proc fs entry - corresponding to your controller after boot-up. - -6. Parity checking - -The driver supports SCSI parity checking and PCI bus master parity -checking. These features must be enabled in order to ensure safe data -transfers. However, some flawed devices or mother boards will have -problems with parity. You can disable either PCI parity or SCSI parity -checking by entering appropriate options from the boot command line. -(See 10: Boot setup commands). - -7. Profiling information - -Profiling information is available through the proc SCSI file system. -Since gathering profiling information may impact performances, this -feature is disabled by default and requires a compilation configuration -option to be set to Y. - -The device associated with a host has the following pathname: - - /proc/scsi/ncr53c8xx/N (N=0,1,2 ....) - -Generally, only 1 board is used on hardware configuration, and that device is: - /proc/scsi/ncr53c8xx/0 - -However, if the driver has been made as module, the number of the -hosts is incremented each time the driver is loaded. - -In order to display profiling information, just enter: - - cat /proc/scsi/ncr53c8xx/0 - -and you will get something like the following text: - -------------------------------------------------------- -General information: - Chip NCR53C810, device id 0x1, revision id 0x2 - IO port address 0x6000, IRQ number 10 - Using memory mapped IO at virtual address 0x282c000 - Synchronous transfer period 25, max commands per lun 4 -Profiling information: - num_trans = 18014 - num_kbytes = 671314 - num_disc = 25763 - num_break = 1673 - num_int = 1685 - num_fly = 18038 - ms_setup = 4940 - ms_data = 369940 - ms_disc = 183090 - ms_post = 1320 -------------------------------------------------------- - -General information is easy to understand. The device ID and the -revision ID identify the SCSI chip as follows: - -Chip Device id Revision Id ----- --------- ----------- -810 0x1 < 0x10 -810A 0x1 >= 0x10 -815 0x4 -825 0x3 < 0x10 -860 0x6 -825A 0x3 >= 0x10 -875 0xf -895 0xc - -The profiling information is updated upon completion of SCSI commands. -A data structure is allocated and zeroed when the host adapter is -attached. So, if the driver is a module, the profile counters are -cleared each time the driver is loaded. The "clearprof" command -allows you to clear these counters at any time. - -The following counters are available: - -("num" prefix means "number of", -"ms" means milli-seconds) - -num_trans - Number of completed commands - Example above: 18014 completed commands - -num_kbytes - Number of kbytes transferred - Example above: 671 MB transferred - -num_disc - Number of SCSI disconnections - Example above: 25763 SCSI disconnections - -num_break - number of script interruptions (phase mismatch) - Example above: 1673 script interruptions - -num_int - Number of interrupts other than "on the fly" - Example above: 1685 interruptions not "on the fly" - -num_fly - Number of interrupts "on the fly" - Example above: 18038 interruptions "on the fly" - -ms_setup - Elapsed time for SCSI commands setups - Example above: 4.94 seconds - -ms_data - Elapsed time for data transfers - Example above: 369.94 seconds spent for data transfer - -ms_disc - Elapsed time for SCSI disconnections - Example above: 183.09 seconds spent disconnected - -ms_post - Elapsed time for command post processing - (time from SCSI status get to command completion call) - Example above: 1.32 seconds spent for post processing - -Due to the 1/100 second tick of the system clock, "ms_post" time may -be wrong. - -In the example above, we got 18038 interrupts "on the fly" and only -1673 script breaks generally due to disconnections inside a segment -of the scatter list. - - -8. Control commands - -Control commands can be sent to the driver with write operations to -the proc SCSI file system. The generic command syntax is the -following: - - echo "<verb> <parameters>" >/proc/scsi/ncr53c8xx/0 - (assumes controller number is 0) - -Using "all" for "<target>" parameter with the commands below will -apply to all targets of the SCSI chain (except the controller). - -Available commands: - -8.1 Set minimum synchronous period factor - - setsync <target> <period factor> - - target: target number - period: minimum synchronous period. - Maximum speed = 1000/(4*period factor) except for special - cases below. - - Specify a period of 255, to force asynchronous transfer mode. - - 10 means 25 nano-seconds synchronous period - 11 means 30 nano-seconds synchronous period - 12 means 50 nano-seconds synchronous period - -8.2 Set wide size - - setwide <target> <size> - - target: target number - size: 0=8 bits, 1=16bits - -8.3 Set maximum number of concurrent tagged commands - - settags <target> <tags> - - target: target number - tags: number of concurrent tagged commands - must not be greater than SCSI_NCR_MAX_TAGS (default: 8) - -8.4 Set order type for tagged command - - setorder <order> - - order: 3 possible values: - simple: use SIMPLE TAG for all operations (read and write) - ordered: use ORDERED TAG for all operations - default: use default tag type, - SIMPLE TAG for read operations - ORDERED TAG for write operations - - -8.5 Set debug mode - - setdebug <list of debug flags> - - Available debug flags: - alloc: print info about memory allocations (ccb, lcb) - queue: print info about insertions into the command start queue - result: print sense data on CHECK CONDITION status - scatter: print info about the scatter process - scripts: print info about the script binding process - tiny: print minimal debugging information - timing: print timing information of the NCR chip - nego: print information about SCSI negotiations - phase: print information on script interruptions - - Use "setdebug" with no argument to reset debug flags. - - -8.6 Clear profile counters - - clearprof - - The profile counters are automatically cleared when the amount of - data transferred reaches 1000 GB in order to avoid overflow. - The "clearprof" command allows you to clear these counters at any time. - - -8.7 Set flag (no_disc) - - setflag <target> <flag> - - target: target number - - For the moment, only one flag is available: - - no_disc: not allow target to disconnect. - - Do not specify any flag in order to reset the flag. For example: - - setflag 4 - will reset no_disc flag for target 4, so will allow it disconnections. - - setflag all - will allow disconnection for all devices on the SCSI bus. - - -8.8 Set verbose level - - setverbose #level - - The driver default verbose level is 1. This command allows to change - th driver verbose level after boot-up. - -8.9 Reset all logical units of a target - - resetdev <target> - - target: target number - The driver will try to send a BUS DEVICE RESET message to the target. - (Only supported by the SYM53C8XX driver and provided for test purpose) - -8.10 Abort all tasks of all logical units of a target - - cleardev <target> - - target: target number - The driver will try to send a ABORT message to all the logical units - of the target. - (Only supported by the SYM53C8XX driver and provided for test purpose) - - -9. Configuration parameters - -If the firmware of all your devices is perfect enough, all the -features supported by the driver can be enabled at start-up. However, -if only one has a flaw for some SCSI feature, you can disable the -support by the driver of this feature at linux start-up and enable -this feature after boot-up only for devices that support it safely. - -CONFIG_SCSI_NCR53C8XX_IOMAPPED (default answer: n) - Answer "y" if you suspect your mother board to not allow memory mapped I/O. - May slow down performance a little. This option is required by - Linux/PPC and is used no matter what you select here. Linux/PPC - suffers no performance loss with this option since all IO is memory - mapped anyway. - -CONFIG_SCSI_NCR53C8XX_DEFAULT_TAGS (default answer: 8) - Default tagged command queue depth. - -CONFIG_SCSI_NCR53C8XX_MAX_TAGS (default answer: 8) - This option allows you to specify the maximum number of tagged commands - that can be queued to a device. The maximum supported value is 32. - -CONFIG_SCSI_NCR53C8XX_SYNC (default answer: 5) - This option allows you to specify the frequency in MHz the driver - will use at boot time for synchronous data transfer negotiations. - This frequency can be changed later with the "setsync" control command. - 0 means "asynchronous data transfers". - -CONFIG_SCSI_NCR53C8XX_FORCE_SYNC_NEGO (default answer: n) - Force synchronous negotiation for all SCSI-2 devices. - Some SCSI-2 devices do not report this feature in byte 7 of inquiry - response but do support it properly (TAMARACK scanners for example). - -CONFIG_SCSI_NCR53C8XX_NO_DISCONNECT (default and only reasonable answer: n) - If you suspect a device of yours does not properly support disconnections, - you can answer "y". Then, all SCSI devices will never disconnect the bus - even while performing long SCSI operations. - -CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT - Genuine SYMBIOS boards use GPIO0 in output for controller LED and GPIO3 - bit as a flag indicating singled-ended/differential interface. - If all the boards of your system are genuine SYMBIOS boards or use - BIOS and drivers from SYMBIOS, you would want to enable this option. - This option must NOT be enabled if your system has at least one 53C8XX - based scsi board with a vendor-specific BIOS. - For example, Tekram DC-390/U, DC-390/W and DC-390/F scsi controllers - use a vendor-specific BIOS and are known to not use SYMBIOS compatible - GPIO wiring. So, this option must not be enabled if your system has - such a board installed. - -CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT - Enable support for reading the serial NVRAM data on Symbios and - some Symbios compatible cards, and Tekram DC390W/U/F cards. Useful for - systems with more than one Symbios compatible controller where at least - one has a serial NVRAM, or for a system with a mixture of Symbios and - Tekram cards. Enables setting the boot order of host adaptors - to something other than the default order or "reverse probe" order. - Also enables Symbios and Tekram cards to be distinguished so - CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT may be set in a system with a - mixture of Symbios and Tekram cards so the Symbios cards can make use of - the full range of Symbios features, differential, led pin, without - causing problems for the Tekram card(s). - -10. Boot setup commands - -10.1 Syntax - -Setup commands can be passed to the driver either at boot time or as a -string variable using 'insmod'. - -A boot setup command for the ncr53c8xx (sym53c8xx) driver begins with the -driver name "ncr53c8xx="(sym53c8xx). The kernel syntax parser then expects -an optional list of integers separated with comma followed by an optional -list of comma-separated strings. Example of boot setup command under lilo -prompt: - -lilo: linux root=/dev/hda2 ncr53c8xx=tags:4,sync:10,debug:0x200 - -- enable tagged commands, up to 4 tagged commands queued. -- set synchronous negotiation speed to 10 Mega-transfers / second. -- set DEBUG_NEGO flag. - -Since comma seems not to be allowed when defining a string variable using -'insmod', the driver also accepts <space> as option separator. -The following command will install driver module with the same options as -above. - - insmod ncr53c8xx.o ncr53c8xx="tags:4 sync:10 debug:0x200" - -For the moment, the integer list of arguments is discarded by the driver. -It will be used in the future in order to allow a per controller setup. - -Each string argument must be specified as "keyword:value". Only lower-case -characters and digits are allowed. - -In a system that contains multiple 53C8xx adapters insmod will install the -specified driver on each adapter. To exclude a chip use the 'excl' keyword. - -The sequence of commands, - - insmod sym53c8xx sym53c8xx=excl:0x1400 - insmod ncr53c8xx - -installs the sym53c8xx driver on all adapters except the one at IO port -address 0x1400 and then installs the ncr53c8xx driver to the adapter at IO -port address 0x1400. - - -10.2 Available arguments - -10.2.1 Master parity checking - mpar:y enabled - mpar:n disabled - -10.2.2 Scsi parity checking - spar:y enabled - spar:n disabled - -10.2.3 Scsi disconnections - disc:y enabled - disc:n disabled - -10.2.4 Special features - Only apply to 810A, 825A, 860, 875 and 895 controllers. - Have no effect with other ones. - specf:y (or 1) enabled - specf:n (or 0) disabled - specf:3 enabled except Memory Write And Invalidate - The default driver setup is 'specf:3'. As a consequence, option 'specf:y' - must be specified in the boot setup command to enable Memory Write And - Invalidate. - -10.2.5 Ultra SCSI support - Only apply to 860, 875, 895, 895a, 896, 1010 and 1010_66 controllers. - Have no effect with other ones. - ultra:n All ultra speeds enabled - ultra:2 Ultra2 enabled - ultra:1 Ultra enabled - ultra:0 Ultra speeds disabled - -10.2.6 Default number of tagged commands - tags:0 (or tags:1 ) tagged command queuing disabled - tags:#tags (#tags > 1) tagged command queuing enabled - #tags will be truncated to the max queued commands configuration parameter. - This option also allows to specify a command queue depth for each device - that support tagged command queueing. - Example: - ncr53c8xx=tags:10/t2t3q16-t5q24/t1u2q32 - will set devices queue depth as follow: - - controller #0 target #2 and target #3 -> 16 commands, - - controller #0 target #5 -> 24 commands, - - controller #1 target #1 logical unit #2 -> 32 commands, - - all other logical units (all targets, all controllers) -> 10 commands. - -10.2.7 Default synchronous period factor - sync:255 disabled (asynchronous transfer mode) - sync:#factor - #factor = 10 Ultra-2 SCSI 40 Mega-transfers / second - #factor = 11 Ultra-2 SCSI 33 Mega-transfers / second - #factor < 25 Ultra SCSI 20 Mega-transfers / second - #factor < 50 Fast SCSI-2 - - In all cases, the driver will use the minimum transfer period supported by - controllers according to NCR53C8XX chip type. - -10.2.8 Negotiate synchronous with all devices - (force sync nego) - fsn:y enabled - fsn:n disabled - -10.2.9 Verbosity level - verb:0 minimal - verb:1 normal - verb:2 too much - -10.2.10 Debug mode - debug:0 clear debug flags - debug:#x set debug flags - #x is an integer value combining the following power-of-2 values: - DEBUG_ALLOC 0x1 - DEBUG_PHASE 0x2 - DEBUG_POLL 0x4 - DEBUG_QUEUE 0x8 - DEBUG_RESULT 0x10 - DEBUG_SCATTER 0x20 - DEBUG_SCRIPT 0x40 - DEBUG_TINY 0x80 - DEBUG_TIMING 0x100 - DEBUG_NEGO 0x200 - DEBUG_TAGS 0x400 - DEBUG_FREEZE 0x800 - DEBUG_RESTART 0x1000 - - You can play safely with DEBUG_NEGO. However, some of these flags may - generate bunches of syslog messages. - -10.2.11 Burst max - burst:0 burst disabled - burst:255 get burst length from initial IO register settings. - burst:#x burst enabled (1<<#x burst transfers max) - #x is an integer value which is log base 2 of the burst transfers max. - The NCR53C875 and NCR53C825A support up to 128 burst transfers (#x = 7). - Other chips only support up to 16 (#x = 4). - This is a maximum value. The driver set the burst length according to chip - and revision ids. By default the driver uses the maximum value supported - by the chip. - -10.2.12 LED support - led:1 enable LED support - led:0 disable LED support - Donnot enable LED support if your scsi board does not use SDMS BIOS. - (See 'Configuration parameters') - -10.2.13 Max wide - wide:1 wide scsi enabled - wide:0 wide scsi disabled - Some scsi boards use a 875 (ultra wide) and only supply narrow connectors. - If you have connected a wide device with a 50 pins to 68 pins cable - converter, any accepted wide negotiation will break further data transfers. - In such a case, using "wide:0" in the bootup command will be helpful. - -10.2.14 Differential mode - diff:0 never set up diff mode - diff:1 set up diff mode if BIOS set it - diff:2 always set up diff mode - diff:3 set diff mode if GPIO3 is not set - -10.2.15 IRQ mode - irqm:0 always open drain - irqm:1 same as initial settings (assumed BIOS settings) - irqm:2 always totem pole - irqm:0x10 driver will not use IRQF_SHARED flag when requesting irq - - (Bits 0x10 and 0x20 can be combined with hardware irq mode option) - -10.2.16 Reverse probe - revprob:n probe chip ids from the PCI configuration in this order: - 810, 815, 820, 860, 875, 885, 895, 896 - revprob:y probe chip ids in the reverse order. - -10.2.17 Fix up PCI configuration space - pcifix:<option bits> - - Available option bits: - 0x0: No attempt to fix PCI configuration space registers values. - 0x1: Set PCI cache-line size register if not set. - 0x2: Set write and invalidate bit in PCI command register. - 0x4: Increase if necessary PCI latency timer according to burst max. - - Use 'pcifix:7' in order to allow the driver to fix up all PCI features. - -10.2.18 Serial NVRAM - nvram:n do not look for serial NVRAM - nvram:y test controllers for onboard serial NVRAM - (alternate binary form) - mvram=<bits options> - 0x01 look for NVRAM (equivalent to nvram=y) - 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices - 0x04 ignore NVRAM "Wide negotiation" parameter for all devices - 0x08 ignore NVRAM "Scan at boot time" parameter for all devices - 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only) - -10.2.19 Check SCSI BUS - buschk:<option bits> - - Available option bits: - 0x0: No check. - 0x1: Check and do not attach the controller on error. - 0x2: Check and just warn on error. - 0x4: Disable SCSI bus integrity checking. - -10.2.20 Exclude a host from being attached - excl=<io_address> - - Prevent host at a given io address from being attached. - For example 'ncr53c8xx=excl:0xb400,excl:0xc000' indicate to the - ncr53c8xx driver not to attach hosts at address 0xb400 and 0xc000. - -10.2.21 Suggest a default SCSI id for hosts - hostid:255 no id suggested. - hostid:#x (0 < x < 7) x suggested for hosts SCSI id. - - If a host SCSI id is available from the NVRAM, the driver will ignore - any value suggested as boot option. Otherwise, if a suggested value - different from 255 has been supplied, it will use it. Otherwise, it will - try to deduce the value previously set in the hardware and use value - 7 if the hardware value is zero. - -10.2.22 Enable use of IMMEDIATE ARBITRATION - (only supported by the sym53c8xx driver. See 10.7 for more details) - iarb:0 do not use this feature. - iarb:#x use this feature according to bit fields as follow: - - bit 0 (1) : enable IARB each time the initiator has been reselected - when it arbitrated for the SCSI BUS. - (#x >> 4) : maximum number of successive settings of IARB if the initiator - win arbitration and it has other commands to send to a device. - -Boot fail safe - safe:y load the following assumed fail safe initial setup - - master parity disabled mpar:n - scsi parity enabled spar:y - disconnections not allowed disc:n - special features disabled specf:n - ultra scsi disabled ultra:n - force sync negotiation disabled fsn:n - reverse probe disabled revprob:n - PCI fix up disabled pcifix:0 - serial NVRAM enabled nvram:y - verbosity level 2 verb:2 - tagged command queuing disabled tags:0 - synchronous negotiation disabled sync:255 - debug flags none debug:0 - burst length from BIOS settings burst:255 - LED support disabled led:0 - wide support disabled wide:0 - settle time 10 seconds settle:10 - differential support from BIOS settings diff:1 - irq mode from BIOS settings irqm:1 - SCSI BUS check do not attach on error buschk:1 - immediate arbitration disabled iarb:0 - -10.3 Advised boot setup commands - -If the driver has been configured with default options, the equivalent -boot setup is: - - ncr53c8xx=mpar:y,spar:y,disc:y,specf:3,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\ - tags:0,sync:50,debug:0,burst:7,led:0,wide:1,settle:2,diff:0,irqm:0 - -For an installation diskette or a safe but not fast system, -boot setup can be: - - ncr53c8xx=safe:y,mpar:y,disc:y - ncr53c8xx=safe:y,disc:y - ncr53c8xx=safe:y,mpar:y - ncr53c8xx=safe:y - -My personal system works flawlessly with the following equivalent setup: - - ncr53c8xx=mpar:y,spar:y,disc:y,specf:1,fsn:n,ultra:2,fsn:n,revprob:n,verb:1\ - tags:32,sync:12,debug:0,burst:7,led:1,wide:1,settle:2,diff:0,irqm:0 - -The driver prints its actual setup when verbosity level is 2. You can try -"ncr53c8xx=verb:2" to get the "static" setup of the driver, or add "verb:2" -to your boot setup command in order to check the actual setup the driver is -using. - -10.4 PCI configuration fix-up boot option - -pcifix:<option bits> - -Available option bits: - 0x1: Set PCI cache-line size register if not set. - 0x2: Set write and invalidate bit in PCI command register. - -Use 'pcifix:3' in order to allow the driver to fix both PCI features. - -These options only apply to new SYMBIOS chips 810A, 825A, 860, 875 -and 895 and are only supported for Pentium and 486 class processors. -Recent SYMBIOS 53C8XX scsi processors are able to use PCI read multiple -and PCI write and invalidate commands. These features require the -cache line size register to be properly set in the PCI configuration -space of the chips. On the other hand, chips will use PCI write and -invalidate commands only if the corresponding bit is set to 1 in the -PCI command register. - -Not all PCI bioses set the PCI cache line register and the PCI write and -invalidate bit in the PCI configuration space of 53C8XX chips. -Optimized PCI accesses may be broken for some PCI/memory controllers or -make problems with some PCI boards. - -This fix-up worked flawlessly on my previous system. -(MB Triton HX / 53C875 / 53C810A) -I use these options at my own risks as you will do if you decide to -use them too. - - -10.5 Serial NVRAM support boot option - -nvram:n do not look for serial NVRAM -nvram:y test controllers for onboard serial NVRAM - -This option can also been entered as an hexadecimal value that allows -to control what information the driver will get from the NVRAM and what -information it will ignore. -For details see '17. Serial NVRAM support'. - -When this option is enabled, the driver tries to detect all boards using -a Serial NVRAM. This memory is used to hold user set up parameters. - -The parameters the driver is able to get from the NVRAM depend on the -data format used, as follow: - - Tekram format Symbios format -General and host parameters - Boot order N Y - Host SCSI ID Y Y - SCSI parity checking Y Y - Verbose boot messages N Y -SCSI devices parameters - Synchronous transfer speed Y Y - Wide 16 / Narrow Y Y - Tagged Command Queuing enabled Y Y - Disconnections enabled Y Y - Scan at boot time N Y - -In order to speed up the system boot, for each device configured without -the "scan at boot time" option, the driver forces an error on the -first TEST UNIT READY command received for this device. - -Some SDMS BIOS revisions seem to be unable to boot cleanly with very fast -hard disks. In such a situation you cannot configure the NVRAM with -optimized parameters value. - -The 'nvram' boot option can be entered in hexadecimal form in order -to ignore some options configured in the NVRAM, as follow: - -mvram=<bits options> - 0x01 look for NVRAM (equivalent to nvram=y) - 0x02 ignore NVRAM "Synchronous negotiation" parameters for all devices - 0x04 ignore NVRAM "Wide negotiation" parameter for all devices - 0x08 ignore NVRAM "Scan at boot time" parameter for all devices - 0x80 also attach controllers set to OFF in the NVRAM (sym53c8xx only) - -Option 0x80 is only supported by the sym53c8xx driver and is disabled by -default. Result is that, by default (option not set), the sym53c8xx driver -will not attach controllers set to OFF in the NVRAM. - -The ncr53c8xx always tries to attach all the controllers. Option 0x80 has -not been added to the ncr53c8xx driver, since it has been reported to -confuse users who use this driver since a long time. If you desire a -controller not to be attached by the ncr53c8xx driver at Linux boot, you -must use the 'excl' driver boot option. - -10.6 SCSI BUS checking boot option. - -When this option is set to a non-zero value, the driver checks SCSI lines -logic state, 100 micro-seconds after having asserted the SCSI RESET line. -The driver just reads SCSI lines and checks all lines read FALSE except RESET. -Since SCSI devices shall release the BUS at most 800 nano-seconds after SCSI -RESET has been asserted, any signal to TRUE may indicate a SCSI BUS problem. -Unfortunately, the following common SCSI BUS problems are not detected: -- Only 1 terminator installed. -- Misplaced terminators. -- Bad quality terminators. -On the other hand, either bad cabling, broken devices, not conformant -devices, ... may cause a SCSI signal to be wrong when te driver reads it. - -10.7 IMMEDIATE ARBITRATION boot option - -This option is only supported by the SYM53C8XX driver (not by the NCR53C8XX). - -SYMBIOS 53C8XX chips are able to arbitrate for the SCSI BUS as soon as they -have detected an expected disconnection (BUS FREE PHASE). For this process -to be started, bit 1 of SCNTL1 IO register must be set when the chip is -connected to the SCSI BUS. - -When this feature has been enabled for the current connection, the chip has -every chance to win arbitration if only devices with lower priority are -competing for the SCSI BUS. By the way, when the chip is using SCSI id 7, -then it will for sure win the next SCSI BUS arbitration. - -Since, there is no way to know what devices are trying to arbitrate for the -BUS, using this feature can be extremely unfair. So, you are not advised -to enable it, or at most enable this feature for the case the chip lost -the previous arbitration (boot option 'iarb:1'). - -This feature has the following advantages: - -a) Allow the initiator with ID 7 to win arbitration when it wants so. -b) Overlap at least 4 micro-seconds of arbitration time with the execution - of SCRIPTS that deal with the end of the current connection and that - starts the next job. - -Hmmm... But (a) may just prevent other devices from reselecting the initiator, -and delay data transfers or status/completions, and (b) may just waste -SCSI BUS bandwidth if the SCRIPTS execution lasts more than 4 micro-seconds. - -The use of IARB needs the SCSI_NCR_IARB_SUPPORT option to have been defined -at compile time and the 'iarb' boot option to have been set to a non zero -value at boot time. It is not that useful for real work, but can be used -to stress SCSI devices or for some applications that can gain advantage of -it. By the way, if you experience badnesses like 'unexpected disconnections', -'bad reselections', etc... when using IARB on heavy IO load, you should not -be surprised, because force-feeding anything and blocking its arse at the -same time cannot work for a long time. :-)) - - -11. Some constants and flags of the ncr53c8xx.h header file - -Some of these are defined from the configuration parameters. To -change other "defines", you must edit the header file. Do that only -if you know what you are doing. - -SCSI_NCR_SETUP_SPECIAL_FEATURES (default: defined) - If defined, the driver will enable some special features according - to chip and revision id. - For 810A, 860, 825A, 875 and 895 scsi chips, this option enables - support of features that reduce load of PCI bus and memory accesses - during scsi transfer processing: burst op-code fetch, read multiple, - read line, prefetch, cache line, write and invalidate, - burst 128 (875 only), large dma fifo (875 only), offset 16 (875 only). - Can be changed by the following boot setup command: - ncr53c8xx=specf:n - -SCSI_NCR_IOMAPPED (default: not defined) - If defined, normal I/O is forced. - -SCSI_NCR_SHARE_IRQ (default: defined) - If defined, request shared IRQ. - -SCSI_NCR_MAX_TAGS (default: 8) - Maximum number of simultaneous tagged commands to a device. - Can be changed by "settags <target> <maxtags>" - -SCSI_NCR_SETUP_DEFAULT_SYNC (default: 50) - Transfer period factor the driver will use at boot time for synchronous - negotiation. 0 means asynchronous. - Can be changed by "setsync <target> <period factor>" - -SCSI_NCR_SETUP_DEFAULT_TAGS (default: 8) - Default number of simultaneous tagged commands to a device. - < 1 means tagged command queuing disabled at start-up. - -SCSI_NCR_ALWAYS_SIMPLE_TAG (default: defined) - Use SIMPLE TAG for read and write commands. - Can be changed by "setorder <ordered|simple|default>" - -SCSI_NCR_SETUP_DISCONNECTION (default: defined) - If defined, targets are allowed to disconnect. - -SCSI_NCR_SETUP_FORCE_SYNC_NEGO (default: not defined) - If defined, synchronous negotiation is tried for all SCSI-2 devices. - Can be changed by "setsync <target> <period>" - -SCSI_NCR_SETUP_MASTER_PARITY (default: defined) - If defined, master parity checking is enabled. - -SCSI_NCR_SETUP_SCSI_PARITY (default: defined) - If defined, SCSI parity checking is enabled. - -SCSI_NCR_PROFILE_SUPPORT (default: not defined) - If defined, profiling information is gathered. - -SCSI_NCR_MAX_SCATTER (default: 128) - Scatter list size of the driver ccb. - -SCSI_NCR_MAX_TARGET (default: 16) - Max number of targets per host. - -SCSI_NCR_MAX_HOST (default: 2) - Max number of host controllers. - -SCSI_NCR_SETTLE_TIME (default: 2) - Number of seconds the driver will wait after reset. - -SCSI_NCR_TIMEOUT_ALERT (default: 3) - If a pending command will time out after this amount of seconds, - an ordered tag is used for the next command. - Avoids timeouts for unordered tagged commands. - -SCSI_NCR_CAN_QUEUE (default: 7*SCSI_NCR_MAX_TAGS) - Max number of commands that can be queued to a host. - -SCSI_NCR_CMD_PER_LUN (default: SCSI_NCR_MAX_TAGS) - Max number of commands queued to a host for a device. - -SCSI_NCR_SG_TABLESIZE (default: SCSI_NCR_MAX_SCATTER-1) - Max size of the Linux scatter/gather list. - -SCSI_NCR_MAX_LUN (default: 8) - Max number of LUNs per target. - - -12. Installation - -This driver is part of the linux kernel distribution. -Driver files are located in the sub-directory "drivers/scsi" of the -kernel source tree. - -Driver files: - - README.ncr53c8xx : this file - ChangeLog.ncr53c8xx : change log - ncr53c8xx.h : definitions - ncr53c8xx.c : the driver code - -New driver versions are made available separately in order to allow testing -changes and new features prior to including them into the linux kernel -distribution. The following URL provides information on latest available -patches: - - ftp://ftp.tux.org/pub/people/gerard-roudier/README - - -13. Architecture dependent features. - -<Not yet written> - - -14. Known problems - -14.1 Tagged commands with Iomega Jaz device - -I have not tried this device, however it has been reported to me the -following: This device is capable of Tagged command queuing. However -while spinning up, it rejects Tagged commands. This behaviour is -conforms to 6.8.2 of SCSI-2 specifications. The current behaviour of -the driver in that situation is not satisfying. So do not enable -Tagged command queuing for devices that are able to spin down. The -other problem that may appear is timeouts. The only way to avoid -timeouts seems to edit linux/drivers/scsi/sd.c and to increase the -current timeout values. - -14.2 Device names change when another controller is added. - -When you add a new NCR53C8XX chip based controller to a system that already -has one or more controllers of this family, it may happen that the order -the driver registers them to the kernel causes problems due to device -name changes. -When at least one controller uses NvRAM, SDMS BIOS version 4 allows you to -define the order the BIOS will scan the scsi boards. The driver attaches -controllers according to BIOS information if NvRAM detect option is set. - -If your controllers do not have NvRAM, you can: - -- Ask the driver to probe chip ids in reverse order from the boot command - line: ncr53c8xx=revprob:y -- Make appropriate changes in the fstab. -- Use the 'scsidev' tool from Eric Youngdale. - -14.3 Using only 8 bit devices with a WIDE SCSI controller. - -When only 8 bit NARROW devices are connected to a 16 bit WIDE SCSI controller, -you must ensure that lines of the wide part of the SCSI BUS are pulled-up. -This can be achieved by ENABLING the WIDE TERMINATOR portion of the SCSI -controller card. -The TYAN 1365 documentation revision 1.2 is not correct about such settings. -(page 10, figure 3.3). - -14.4 Possible data corruption during a Memory Write and Invalidate - -This problem is described in SYMBIOS DEL 397, Part Number 69-039241, ITEM 4. - -In some complex situations, 53C875 chips revision <= 3 may start a PCI -Write and Invalidate Command at a not cache-line-aligned 4 DWORDS boundary. -This is only possible when Cache Line Size is 8 DWORDS or greater. -Pentium systems use a 8 DWORDS cache line size and so are concerned by -this chip bug, unlike i486 systems that use a 4 DWORDS cache line size. - -When this situation occurs, the chip may complete the Write and Invalidate -command after having only filled part of the last cache line involved in -the transfer, leaving to data corruption the remainder of this cache line. - -Not using Write And Invalidate obviously gets rid of this chip bug, and so -it is now the default setting of the driver. -However, for people like me who want to enable this feature, I have added -part of a work-around suggested by SYMBIOS. This work-around resets the -addressing logic when the DATA IN phase is entered and so prevents the bug -from being triggered for the first SCSI MOVE of the phase. This work-around -should be enough according to the following: - -The only driver internal data structure that is greater than 8 DWORDS and -that is moved by the SCRIPTS processor is the 'CCB header' that contains -the context of the SCSI transfer. This data structure is aligned on 8 DWORDS -boundary (Pentium Cache Line Size), and so is immune to this chip bug, at -least on Pentium systems. -But the conditions of this bug can be met when a SCSI read command is -performed using a buffer that is 4 DWORDS but not cache-line aligned. -This cannot happen under Linux when scatter/gather lists are used since -they only refer to system buffers that are well aligned. So, a work around -may only be needed under Linux when a scatter/gather list is not used and -when the SCSI DATA IN phase is reentered after a phase mismatch. - -15. SCSI problem troubleshooting - -15.1 Problem tracking - -Most SCSI problems are due to a non conformant SCSI bus or to buggy -devices. If unfortunately you have SCSI problems, you can check the -following things: - -- SCSI bus cables -- terminations at both end of the SCSI chain -- linux syslog messages (some of them may help you) - -If you do not find the source of problems, you can configure the -driver with no features enabled. - -- only asynchronous data transfers -- tagged commands disabled -- disconnections not allowed - -Now, if your SCSI bus is ok, your system have every chance to work -with this safe configuration but performances will not be optimal. - -If it still fails, then you can send your problem description to -appropriate mailing lists or news-groups. Send me a copy in order to -be sure I will receive it. Obviously, a bug in the driver code is -possible. - - My email address: Gerard Roudier <groudier@free.fr> - -Allowing disconnections is important if you use several devices on -your SCSI bus but often causes problems with buggy devices. -Synchronous data transfers increases throughput of fast devices like -hard disks. Good SCSI hard disks with a large cache gain advantage of -tagged commands queuing. - -Try to enable one feature at a time with control commands. For example: - -- echo "setsync all 25" >/proc/scsi/ncr53c8xx/0 - Will enable fast synchronous data transfer negotiation for all targets. - -- echo "setflag 3" >/proc/scsi/ncr53c8xx/0 - Will reset flags (no_disc) for target 3, and so will allow it to disconnect - the SCSI Bus. - -- echo "settags 3 8" >/proc/scsi/ncr53c8xx/0 - Will enable tagged command queuing for target 3 if that device supports it. - -Once you have found the device and the feature that cause problems, just -disable that feature for that device. - -15.2 Understanding hardware error reports - -When the driver detects an unexpected error condition, it may display a -message of the following pattern. - -sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000). -sym53c876-0: script cmd = 19000000 -sym53c876-0: regdump: da 10 80 95 47 0f 01 07 75 01 81 21 80 01 09 00. - -Some fields in such a message may help you understand the cause of the -problem, as follows: - -sym53c876-0:1: ERROR (0:48) (1-21-65) (f/95) @ (script 7c0:19000000). -............A.........B.C....D.E..F....G.H.......I.....J...K....... - -Field A : target number. - SCSI ID of the device the controller was talking with at the moment the - error occurs. - -Field B : DSTAT io register (DMA STATUS) - Bit 0x40 : MDPE Master Data Parity Error - Data parity error detected on the PCI BUS. - Bit 0x20 : BF Bus Fault - PCI bus fault condition detected - Bit 0x01 : IID Illegal Instruction Detected - Set by the chip when it detects an Illegal Instruction format - on some condition that makes an instruction illegal. - Bit 0x80 : DFE Dma Fifo Empty - Pure status bit that does not indicate an error. - If the reported DSTAT value contains a combination of MDPE (0x40), - BF (0x20), then the cause may be likely due to a PCI BUS problem. - -Field C : SIST io register (SCSI Interrupt Status) - Bit 0x08 : SGE SCSI GROSS ERROR - Indicates that the chip detected a severe error condition - on the SCSI BUS that prevents the SCSI protocol from functioning - properly. - Bit 0x04 : UDC Unexpected Disconnection - Indicates that the device released the SCSI BUS when the chip - was not expecting this to happen. A device may behave so to - indicate the SCSI initiator that an error condition not reportable using the SCSI protocol has occurred. - Bit 0x02 : RST SCSI BUS Reset - Generally SCSI targets do not reset the SCSI BUS, although any - device on the BUS can reset it at any time. - Bit 0x01 : PAR Parity - SCSI parity error detected. - On a faulty SCSI BUS, any error condition among SGE (0x08), UDC (0x04) and - PAR (0x01) may be detected by the chip. If your SCSI system sometimes - encounters such error conditions, especially SCSI GROSS ERROR, then a SCSI - BUS problem is likely the cause of these errors. - -For fields D,E,F,G and H, you may look into the sym53c8xx_defs.h file -that contains some minimal comments on IO register bits. -Field D : SOCL Scsi Output Control Latch - This register reflects the state of the SCSI control lines the - chip want to drive or compare against. -Field E : SBCL Scsi Bus Control Lines - Actual value of control lines on the SCSI BUS. -Field F : SBDL Scsi Bus Data Lines - Actual value of data lines on the SCSI BUS. -Field G : SXFER SCSI Transfer - Contains the setting of the Synchronous Period for output and - the current Synchronous offset (offset 0 means asynchronous). -Field H : SCNTL3 Scsi Control Register 3 - Contains the setting of timing values for both asynchronous and - synchronous data transfers. - -Understanding Fields I, J, K and dumps requires to have good knowledge of -SCSI standards, chip cores functionnals and internal driver data structures. -You are not required to decode and understand them, unless you want to help -maintain the driver code. - -16. Synchronous transfer negotiation tables - -Tables below have been created by calling the routine the driver uses -for synchronisation negotiation timing calculation and chip setting. -The first table corresponds to Ultra chips 53875 and 53C860 with 80 MHz -clock and 5 clock divisors. -The second one has been calculated by setting the scsi clock to 40 Mhz -and using 4 clock divisors and so applies to all NCR53C8XX chips in fast -SCSI-2 mode. - -Periods are in nano-seconds and speeds are in Mega-transfers per second. -1 Mega-transfers/second means 1 MB/s with 8 bits SCSI and 2 MB/s with -Wide16 SCSI. - -16.1 Synchronous timings for 53C895, 53C875 and 53C860 SCSI controllers - - ---------------------------------------------- - Negotiated NCR settings - Factor Period Speed Period Speed - ------ ------ ------ ------ ------ - 10 25 40.000 25 40.000 (53C895 only) - 11 30.2 33.112 31.25 32.000 (53C895 only) - 12 50 20.000 50 20.000 - 13 52 19.230 62 16.000 - 14 56 17.857 62 16.000 - 15 60 16.666 62 16.000 - 16 64 15.625 75 13.333 - 17 68 14.705 75 13.333 - 18 72 13.888 75 13.333 - 19 76 13.157 87 11.428 - 20 80 12.500 87 11.428 - 21 84 11.904 87 11.428 - 22 88 11.363 93 10.666 - 23 92 10.869 93 10.666 - 24 96 10.416 100 10.000 - 25 100 10.000 100 10.000 - 26 104 9.615 112 8.888 - 27 108 9.259 112 8.888 - 28 112 8.928 112 8.888 - 29 116 8.620 125 8.000 - 30 120 8.333 125 8.000 - 31 124 8.064 125 8.000 - 32 128 7.812 131 7.619 - 33 132 7.575 150 6.666 - 34 136 7.352 150 6.666 - 35 140 7.142 150 6.666 - 36 144 6.944 150 6.666 - 37 148 6.756 150 6.666 - 38 152 6.578 175 5.714 - 39 156 6.410 175 5.714 - 40 160 6.250 175 5.714 - 41 164 6.097 175 5.714 - 42 168 5.952 175 5.714 - 43 172 5.813 175 5.714 - 44 176 5.681 187 5.333 - 45 180 5.555 187 5.333 - 46 184 5.434 187 5.333 - 47 188 5.319 200 5.000 - 48 192 5.208 200 5.000 - 49 196 5.102 200 5.000 - - -16.2 Synchronous timings for fast SCSI-2 53C8XX controllers - - ---------------------------------------------- - Negotiated NCR settings - Factor Period Speed Period Speed - ------ ------ ------ ------ ------ - 25 100 10.000 100 10.000 - 26 104 9.615 125 8.000 - 27 108 9.259 125 8.000 - 28 112 8.928 125 8.000 - 29 116 8.620 125 8.000 - 30 120 8.333 125 8.000 - 31 124 8.064 125 8.000 - 32 128 7.812 131 7.619 - 33 132 7.575 150 6.666 - 34 136 7.352 150 6.666 - 35 140 7.142 150 6.666 - 36 144 6.944 150 6.666 - 37 148 6.756 150 6.666 - 38 152 6.578 175 5.714 - 39 156 6.410 175 5.714 - 40 160 6.250 175 5.714 - 41 164 6.097 175 5.714 - 42 168 5.952 175 5.714 - 43 172 5.813 175 5.714 - 44 176 5.681 187 5.333 - 45 180 5.555 187 5.333 - 46 184 5.434 187 5.333 - 47 188 5.319 200 5.000 - 48 192 5.208 200 5.000 - 49 196 5.102 200 5.000 - - -17. Serial NVRAM (added by Richard Waltham: dormouse@farsrobt.demon.co.uk) - -17.1 Features - -Enabling serial NVRAM support enables detection of the serial NVRAM included -on Symbios and some Symbios compatible host adaptors, and Tekram boards. The -serial NVRAM is used by Symbios and Tekram to hold set up parameters for the -host adaptor and its attached drives. - -The Symbios NVRAM also holds data on the boot order of host adaptors in a -system with more than one host adaptor. This enables the order of scanning -the cards for drives to be changed from the default used during host adaptor -detection. - -This can be done to a limited extent at the moment using "reverse probe" but -this only changes the order of detection of different types of cards. The -NVRAM boot order settings can do this as well as change the order the same -types of cards are scanned in, something "reverse probe" cannot do. - -Tekram boards using Symbios chips, DC390W/F/U, which have NVRAM are detected -and this is used to distinguish between Symbios compatible and Tekram host -adaptors. This is used to disable the Symbios compatible "diff" setting -incorrectly set on Tekram boards if the CONFIG_SCSI_53C8XX_SYMBIOS_COMPAT -configuration parameter is set enabling both Symbios and Tekram boards to be -used together with the Symbios cards using all their features, including -"diff" support. ("led pin" support for Symbios compatible cards can remain -enabled when using Tekram cards. It does nothing useful for Tekram host -adaptors but does not cause problems either.) - - -17.2 Symbios NVRAM layout - -typical data at NVRAM address 0x100 (53c810a NVRAM) ------------------------------------------------------------ -00 00 -64 01 -8e 0b - -00 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00 - -04 00 0f 00 00 10 00 50 00 00 01 00 00 62 -04 00 03 00 00 10 00 58 00 00 01 00 00 63 -04 00 01 00 00 10 00 48 00 00 01 00 00 61 -00 00 00 00 00 00 00 00 00 00 00 00 00 00 - -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 - -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 - -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 - -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 - -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 -00 00 00 00 00 00 00 00 - -fe fe -00 00 -00 00 ------------------------------------------------------------ -NVRAM layout details - -NVRAM Address 0x000-0x0ff not used - 0x100-0x26f initialised data - 0x270-0x7ff not used - -general layout - - header - 6 bytes, - data - 356 bytes (checksum is byte sum of this data) - trailer - 6 bytes - --- - total 368 bytes - -data area layout - - controller set up - 20 bytes - boot configuration - 56 bytes (4x14 bytes) - device set up - 128 bytes (16x8 bytes) - unused (spare?) - 152 bytes (19x8 bytes) - --- - total 356 bytes - ------------------------------------------------------------ -header - -00 00 - ?? start marker -64 01 - byte count (lsb/msb excludes header/trailer) -8e 0b - checksum (lsb/msb excludes header/trailer) ------------------------------------------------------------ -controller set up - -00 30 00 00 00 00 07 00 00 00 00 00 00 00 07 04 10 04 00 00 - | | | | - | | | -- host ID - | | | - | | --Removable Media Support - | | 0x00 = none - | | 0x01 = Bootable Device - | | 0x02 = All with Media - | | - | --flag bits 2 - | 0x00000001= scan order hi->low - | (default 0x00 - scan low->hi) - --flag bits 1 - 0x00000001 scam enable - 0x00000010 parity enable - 0x00000100 verbose boot msgs - -remaining bytes unknown - they do not appear to change in my -current set up for any of the controllers. - -default set up is identical for 53c810a and 53c875 NVRAM -(Removable Media added Symbios BIOS version 4.09) ------------------------------------------------------------ -boot configuration - -boot order set by order of the devices in this table - -04 00 0f 00 00 10 00 50 00 00 01 00 00 62 -- 1st controller -04 00 03 00 00 10 00 58 00 00 01 00 00 63 2nd controller -04 00 01 00 00 10 00 48 00 00 01 00 00 61 3rd controller -00 00 00 00 00 00 00 00 00 00 00 00 00 00 4th controller - | | | | | | | | - | | | | | | ---- PCI io port adr - | | | | | --0x01 init/scan at boot time - | | | | --PCI device/function number (0xdddddfff) - | | ----- ?? PCI vendor ID (lsb/msb) - ----PCI device ID (lsb/msb) - -?? use of this data is a guess but seems reasonable - -remaining bytes unknown - they do not appear to change in my -current set up - -default set up is identical for 53c810a and 53c875 NVRAM ------------------------------------------------------------ -device set up (up to 16 devices - includes controller) - -0f 00 08 08 64 00 0a 00 - id 0 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 - -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 -0f 00 08 08 64 00 0a 00 - id 15 - | | | | | | - | | | | ----timeout (lsb/msb) - | | | --synch period (0x?? 40 Mtrans/sec- fast 40) (probably 0x28) - | | | (0x30 20 Mtrans/sec- fast 20) - | | | (0x64 10 Mtrans/sec- fast ) - | | | (0xc8 5 Mtrans/sec) - | | | (0x00 asynchronous) - | | -- ?? max sync offset (0x08 in NVRAM on 53c810a) - | | (0x10 in NVRAM on 53c875) - | --device bus width (0x08 narrow) - | (0x10 16 bit wide) - --flag bits - 0x00000001 - disconnect enabled - 0x00000010 - scan at boot time - 0x00000100 - scan luns - 0x00001000 - queue tags enabled - -remaining bytes unknown - they do not appear to change in my -current set up - -?? use of this data is a guess but seems reasonable -(but it could be max bus width) - -default set up for 53c810a NVRAM -default set up for 53c875 NVRAM - bus width - 0x10 - - sync offset ? - 0x10 - - sync period - 0x30 ------------------------------------------------------------ -?? spare device space (32 bit bus ??) - -00 00 00 00 00 00 00 00 (19x8bytes) -. -. -00 00 00 00 00 00 00 00 - -default set up is identical for 53c810a and 53c875 NVRAM ------------------------------------------------------------ -trailer - -fe fe - ? end marker ? -00 00 -00 00 - -default set up is identical for 53c810a and 53c875 NVRAM ------------------------------------------------------------ - - - -17.3 Tekram NVRAM layout - -nvram 64x16 (1024 bit) - -Drive settings - -Drive ID 0-15 (addr 0x0yyyy0 = device setup, yyyy = ID) - (addr 0x0yyyy1 = 0x0000) - - x x x x x x x x x x x x x x x x - | | | | | | | | | - | | | | | | | | ----- parity check 0 - off - | | | | | | | | 1 - on - | | | | | | | | - | | | | | | | ------- sync neg 0 - off - | | | | | | | 1 - on - | | | | | | | - | | | | | | --------- disconnect 0 - off - | | | | | | 1 - on - | | | | | | - | | | | | ----------- start cmd 0 - off - | | | | | 1 - on - | | | | | - | | | | -------------- tagged cmds 0 - off - | | | | 1 - on - | | | | - | | | ---------------- wide neg 0 - off - | | | 1 - on - | | | - --------------------------- sync rate 0 - 10.0 Mtrans/sec - 1 - 8.0 - 2 - 6.6 - 3 - 5.7 - 4 - 5.0 - 5 - 4.0 - 6 - 3.0 - 7 - 2.0 - 7 - 2.0 - 8 - 20.0 - 9 - 16.7 - a - 13.9 - b - 11.9 - -Global settings - -Host flags 0 (addr 0x100000, 32) - - x x x x x x x x x x x x x x x x - | | | | | | | | | | | | - | | | | | | | | ----------- host ID 0x00 - 0x0f - | | | | | | | | - | | | | | | | ----------------------- support for 0 - off - | | | | | | | > 2 drives 1 - on - | | | | | | | - | | | | | | ------------------------- support drives 0 - off - | | | | | | > 1Gbytes 1 - on - | | | | | | - | | | | | --------------------------- bus reset on 0 - off - | | | | | power on 1 - on - | | | | | - | | | | ----------------------------- active neg 0 - off - | | | | 1 - on - | | | | - | | | -------------------------------- imm seek 0 - off - | | | 1 - on - | | | - | | ---------------------------------- scan luns 0 - off - | | 1 - on - | | - -------------------------------------- removable 0 - disable - as BIOS dev 1 - boot device - 2 - all - -Host flags 1 (addr 0x100001, 33) - - x x x x x x x x x x x x x x x x - | | | | | | - | | | --------- boot delay 0 - 3 sec - | | | 1 - 5 - | | | 2 - 10 - | | | 3 - 20 - | | | 4 - 30 - | | | 5 - 60 - | | | 6 - 120 - | | | - --------------------------- max tag cmds 0 - 2 - 1 - 4 - 2 - 8 - 3 - 16 - 4 - 32 - -Host flags 2 (addr 0x100010, 34) - - x x x x x x x x x x x x x x x x - | - ----- F2/F6 enable 0 - off ??? - 1 - on ??? - -checksum (addr 0x111111) - -checksum = 0x1234 - (sum addr 0-63) - ----------------------------------------------------------------------------- - -default nvram data: - -0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 -0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 -0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 -0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 0x0037 0x0000 - -0x0f07 0x0400 0x0001 0x0000 0x0000 0x0000 0x0000 0x0000 -0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 -0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 -0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0xfbbc - - -18. Support for Big Endian - -The PCI local bus has been primarily designed for x86 architecture. -As a consequence, PCI devices generally expect DWORDS using little endian -byte ordering. - -18.1 Big Endian CPU - -In order to support NCR chips on a Big Endian architecture the driver has to -perform byte reordering each time it is needed. This feature has been -added to the driver by Cort <cort@cs.nmt.edu> and is available in driver -version 2.5 and later ones. For the moment Big Endian support has only -been tested on Linux/PPC (PowerPC). - -18.2 NCR chip in Big Endian mode of operations - -It can be read in SYMBIOS documentation that some chips support a special -Big Endian mode, on paper: 53C815, 53C825A, 53C875, 53C875N, 53C895. -This mode of operations is not software-selectable, but needs pin named -BigLit to be pulled-up. Using this mode, most of byte reorderings should -be avoided when the driver is running on a Big Endian CPU. -Driver version 2.5 is also, in theory, ready for this feature. - -=============================================================================== -End of NCR53C8XX driver README file |