From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/scsi/sym53c8xx_2.txt | 1048 ++++++++++++++++++++++++++++++++++++ 1 file changed, 1048 insertions(+) create mode 100644 Documentation/scsi/sym53c8xx_2.txt (limited to 'Documentation/scsi/sym53c8xx_2.txt') diff --git a/Documentation/scsi/sym53c8xx_2.txt b/Documentation/scsi/sym53c8xx_2.txt new file mode 100644 index 00000000..6af8f7a7 --- /dev/null +++ b/Documentation/scsi/sym53c8xx_2.txt @@ -0,0 +1,1048 @@ +The Linux SYM-2 driver documentation file + +Written by Gerard Roudier +21 Rue Carnot +95170 DEUIL LA BARRE - FRANCE + +Updated by Matthew Wilcox + +2004-10-09 +=============================================================================== + +1. Introduction +2. Supported chips and SCSI features +3. Advantages of this driver for newer chips. + 3.1 Optimized SCSI SCRIPTS + 3.2 New features appeared with the SYM53C896 +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 debug mode + 8.5 Set flag (no_disc) + 8.6 Set verbose level + 8.7 Reset all logical units of a target + 8.8 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 Default number of tagged commands + 10.2.2 Burst max + 10.2.3 LED support + 10.2.4 Differential mode + 10.2.5 IRQ mode + 10.2.6 Check SCSI BUS + 10.2.7 Suggest a default SCSI id for hosts + 10.2.8 Verbosity level + 10.2.9 Debug mode + 10.2.10 Settle delay + 10.2.11 Serial NVRAM + 10.2.12 Exclude a host from being attached + 10.3 Converting from old options + 10.4 SCSI BUS checking boot option +11. SCSI problem troubleshooting + 15.1 Problem tracking + 15.2 Understanding hardware error reports +12. Serial NVRAM support (by Richard Waltham) + 17.1 Features + 17.2 Symbios NVRAM layout + 17.3 Tekram NVRAM layout + +=============================================================================== + +1. Introduction + +This driver supports the whole SYM53C8XX family of PCI-SCSI controllers. +It also support the subset of LSI53C10XX PCI-SCSI controllers that are based +on the SYM53C8XX SCRIPTS language. + +It replaces the sym53c8xx+ncr53c8xx driver bundle and shares its core code +with the FreeBSD SYM-2 driver. The `glue' that allows this driver to work +under Linux is contained in 2 files named sym_glue.h and sym_glue.c. +Other drivers files are intended not to depend on the Operating System +on which the driver is used. + +The history of this driver can be summarized as follows: + +1993: ncr driver written for 386bsd and FreeBSD by: + Wolfgang Stanglmeier + Stefan Esser + +1996: port of the ncr driver to Linux-1.2.13 and rename it ncr53c8xx. + Gerard Roudier + +1998: new sym53c8xx driver for Linux based on LOAD/STORE instruction and that + adds full support for the 896 but drops support for early NCR devices. + Gerard Roudier + +1999: port of the sym53c8xx driver to FreeBSD and support for the LSI53C1010 + 33 MHz and 66MHz Ultra-3 controllers. The new driver is named `sym'. + Gerard Roudier + +2000: Add support for early NCR devices to FreeBSD `sym' driver. + Break the driver into several sources and separate the OS glue + code from the core code that can be shared among different O/Ses. + Write a glue code for Linux. + Gerard Roudier + +2004: Remove FreeBSD compatibility code. Remove support for versions of + Linux before 2.6. Start using Linux facilities. + +This README file addresses the Linux version of the driver. Under FreeBSD, +the driver documentation is the sym.8 man page. + +Information about new chips is available at LSILOGIC web server: + + http://www.lsilogic.com/ + +SCSI standard documentations are available at T10 site: + + http://www.t10.org/ + +Useful SCSI tools written by Eric Youngdale are part of most Linux +distributions: + scsiinfo: command line tool + scsi-config: TCL/Tk tool using scsiinfo + +2. Supported chips and SCSI features + +The following features are supported for all chips: + + Synchronous negotiation + Disconnection + Tagged command queuing + SCSI parity checking + PCI Master parity checking + +Other features depends on chip capabilities. +The driver notably uses optimized SCRIPTS for devices that support +LOAD/STORE and handles PHASE MISMATCH from SCRIPTS for devices that +support the corresponding feature. + +The following table shows some characteristics of the chip family. + + On board LOAD/STORE HARDWARE +Chip SDMS BIOS Wide SCSI std. Max. sync SCRIPTS PHASE MISMATCH +---- --------- ---- --------- ---------- ---------- -------------- +810 N N FAST10 10 MB/s N N +810A N N FAST10 10 MB/s Y N +815 Y N FAST10 10 MB/s N N +825 Y Y FAST10 20 MB/s N N +825A Y Y FAST10 20 MB/s Y N +860 N N FAST20 20 MB/s Y N +875 Y Y FAST20 40 MB/s Y N +875A Y Y FAST20 40 MB/s Y Y +876 Y Y FAST20 40 MB/s Y N +895 Y Y FAST40 80 MB/s Y N +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 Y Y +1010_66* Y Y FAST80 160 MB/s Y Y + +* Chip supports 33MHz and 66MHz PCI bus clock. + + +Summary of other supported features: + +Module: allow to load the driver +Memory mapped I/O: increases performance +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 this driver for newer chips. + +3.1 Optimized SCSI SCRIPTS. + +All chips except the 810, 815 and 825, 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. + +Due to the lack of LOAD/STORE SCRIPTS instructions by earlier chips, this +driver also incorporates a different SCRIPTS set based on MEMORY MOVE, in +order to provide support for the entire SYM53C8XX chips family. + +3.2 New features appeared with the SYM53C896 + +Newer chips (see above) 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). + +The 896 and 1010 chips support 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. + +4. Memory mapped I/O versus normal I/O + +Memory mapped I/O has less latency than normal I/O and is the recommended +way for doing IO with PCI devices. Memory mapped I/O seems to work fine on +most hardware configurations, but some poorly designed chipsets may break +this feature. A configuration option is provided for normal I/O to be +used but the driver defaults to MMIO. + +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 old 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 I never have had problem with tagged queuing using +this driver and its predecessors. Hard disks that behaved correctly for +me using tagged commands are the following: + +- IBM S12 0662 +- Conner 1080S +- Quantum Atlas I +- Quantum Atlas II +- Seagate Cheetah I +- Quantum Viking II +- IBM DRVS +- Quantum Atlas IV +- Seagate Cheetah 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 16 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. + +This driver supports up to 255 commands per device, and but using more than +64 is generally not worth-while, unless you are using a very large disk or +disk arrays. 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: + + sym53c8xx=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 200 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 'sym53c8xx=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. Some flawed devices or mother boards may have problems +with parity. The options to defeat parity checking have been removed +from the driver. + +7. Profiling information + +This driver does not provide profiling information as did its predecessors. +This feature was not this useful and added complexity to the code. +As the driver code got more complex, I have decided to remove everything +that didn't seem actually useful. + +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 " " >/proc/scsi/sym53c8xx/0 + (assumes controller number is 0) + +Using "all" for "" 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: target number + period: minimum synchronous period. + Maximum speed = 1000/(4*period factor) except for special + cases below. + + Specify a period of 0, to force asynchronous transfer mode. + + 9 means 12.5 nano-seconds synchronous period + 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: target number + size: 0=8 bits, 1=16bits + +8.3 Set maximum number of concurrent tagged commands + + settags + + target: target number + tags: number of concurrent tagged commands + must not be greater than configured (default: 16) + +8.4 Set debug mode + + setdebug + + 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. + + +8.5 Set flag (no_disc) + + setflag + + 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. + + +8.6 Set verbose level + + setverbose #level + + The driver default verbose level is 1. This command allows to change + th driver verbose level after boot-up. + +8.7 Reset all logical units of a target + + resetdev + + target: target number + The driver will try to send a BUS DEVICE RESET message to the target. + +8.8 Abort all tasks of all logical units of a target + + cleardev + + target: target number + The driver will try to send a ABORT message to all the logical units + of the target. + + +9. Configuration parameters + +Under kernel configuration tools (make menuconfig, for example), it is +possible to change some default driver 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. + +Configuration parameters: + +Use normal IO (default answer: n) + Answer "y" if you suspect your mother board to not allow memory mapped I/O. + May slow down performance a little. + +Default tagged command queue depth (default answer: 16) + Entering 0 defaults to tagged commands not being used. + This parameter can be specified from the boot command line. + +Maximum number of queued commands (default answer: 32) + This option allows you to specify the maximum number of tagged commands + that can be queued to a device. The maximum supported value is 255. + +Synchronous transfers frequency (default answer: 80) + This option allows you to specify the frequency in MHz the driver + will use at boot time for synchronous data transfer negotiations. + 0 means "asynchronous data transfers". + +10. Boot setup commands + +10.1 Syntax + +Setup commands can be passed to the driver either at boot time or as +parameters to modprobe, as described in Documentation/kernel-parameters.txt + +Example of boot setup command under lilo prompt: + +lilo: linux root=/dev/sda2 sym53c8xx.cmd_per_lun=4 sym53c8xx.sync=10 sym53c8xx.debug=0x200 + +- enable tagged commands, up to 4 tagged commands queued. +- set synchronous negotiation speed to 10 Mega-transfers / second. +- set DEBUG_NEGO flag. + +The following command will install the driver module with the same +options as above. + + modprobe sym53c8xx cmd_per_lun=4 sync=10 debug=0x200 + +10.2 Available arguments + +10.2.1 Default number of tagged commands + cmd_per_lun=0 (or cmd_per_lun=1) tagged command queuing disabled + cmd_per_lun=#tags (#tags > 1) tagged command queuing enabled + #tags will be truncated to the max queued commands configuration parameter. + +10.2.2 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. + By default the driver uses the maximum value supported by the chip. + +10.2.3 LED support + led=1 enable LED support + led=0 disable LED support + Do not enable LED support if your scsi board does not use SDMS BIOS. + (See 'Configuration parameters') + +10.2.4 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 + +10.2.5 IRQ mode + irqm=0 always open drain + irqm=1 same as initial settings (assumed BIOS settings) + irqm=2 always totem pole + +10.2.6 Check SCSI BUS + buschk=