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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/scsi/sym53c8xx_2.rst | |
parent | Initial commit. (diff) | |
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Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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-rw-r--r-- | Documentation/scsi/sym53c8xx_2.rst | 1209 |
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diff --git a/Documentation/scsi/sym53c8xx_2.rst b/Documentation/scsi/sym53c8xx_2.rst new file mode 100644 index 000000000..8de44a7ba --- /dev/null +++ b/Documentation/scsi/sym53c8xx_2.rst @@ -0,0 +1,1209 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================================= +The Linux SYM-2 driver documentation file +========================================= + +Written by Gerard Roudier <groudier@free.fr> + +21 Rue Carnot + +95170 DEUIL LA BARRE - FRANCE + +Updated by Matthew Wilcox <matthew@wil.cx> + +2004-10-09 + +.. Contents + + 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 <wolf@cologne.de> + - Stefan Esser <se@mi.Uni-Koeln.de> + +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. + ++--------+-----------+-----+-----------+------------+------------+---------+ +| | | | | |Load/store |Hardware | +| |On board | | | |scripts |phase | +|Chip |SDMS BIOS |Wide |SCSI std. | Max. sync | |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 | +|[1]_ | | | | | | | ++--------+-----------+-----+-----------+------------+------------+---------+ + +.. [1] 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) +:Serial NVRAM: Symbios and Tekram formats + +- Scatter / gather +- Shared interrupt +- Boot setup commands + + +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 "<verb> <parameters>" >/proc/scsi/sym53c8xx/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 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> <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 configured (default: 16) + +8.4 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. + + +8.5 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. + + +8.6 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: 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: 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/admin-guide/kernel-parameters.rst + +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=<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. + === ================================================ + +10.2.7 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. + +10.2.8 Verbosity level +^^^^^^^^^^^^^^^^^^^^^^^ + + ====== ======== + verb=0 minimal + verb=1 normal + verb=2 too much + ====== ======== + +10.2.9 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. + +10.2.10 Settle delay +^^^^^^^^^^^^^^^^^^^^ + + ======== =================== + settle=n delay for n seconds + ======== =================== + + After a bus reset, the driver will delay for n seconds before talking + to any device on the bus. The default is 3 seconds and safe mode will + default it to 10. + +10.2.11 Serial NVRAM +^^^^^^^^^^^^^^^^^^^^ + + .. Note:: option not currently implemented. + + ======= ========================================= + nvram=n do not look for serial NVRAM + nvram=y test controllers for onboard serial NVRAM + ======= ========================================= + + (alternate binary form) + + nvram=<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) + ==== ================================================================= + +10.2.12 Exclude a host from being attached +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + + excl=<io_address>,... + + Prevent host at a given io address from being attached. + For example 'excl=0xb400,0xc000' indicate to the + driver not to attach hosts at address 0xb400 and 0xc000. + +10.3 Converting from old style options +-------------------------------------- + +Previously, the sym2 driver accepted arguments of the form:: + + sym53c8xx=tags:4,sync:10,debug:0x200 + +As a result of the new module parameters, this is no longer available. +Most of the options have remained the same, but tags has become +cmd_per_lun to reflect its different purposes. The sample above would +be specified as:: + + modprobe sym53c8xx cmd_per_lun=4 sync=10 debug=0x200 + +or on the kernel boot line as:: + + sym53c8xx.cmd_per_lun=4 sym53c8xx.sync=10 sym53c8xx.debug=0x200 + +10.4 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. + +15. SCSI problem troubleshooting +================================ + +15.1 Problem tracking +--------------------- + +Most SCSI problems are due to a non conformant SCSI bus or too 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 or devices in the NVRAM with minimal features. + +- only asynchronous data transfers +- tagged commands disabled +- disconnections not allowed + +Now, if your SCSI bus is ok, your system has 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 current 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. + +15.2 Understanding hardware error reports +----------------------------------------- + +When the driver detects an unexpected error condition, it may display a +message of the following pattern:: + + sym0:1: ERROR (0:48) (1-21-65) (f/95/0) @ (script 7c0:19000000). + sym0: script cmd = 19000000 + sym0: 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:: + + sym0:1: ERROR (0:48) (1-21-65) (f/95/0) @ (script 7c0:19000000). + .....A.........B.C....D.E..F....G.H..I.......J.....K...L....... + +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. +Field I : SCNTL4 Scsi Control Register 4 + Only meaningful for 53C1010 Ultra3 controllers. + +Understanding Fields J, K, L 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. + +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 information is no longer used +as it's fundamentally incompatible with the hotplug PCI model. + +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.) + +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 | Y | Y | +| enabled | | | ++-------------------------------+------------------+--------------+ +| * 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. + + +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 |