diff options
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
| commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
| tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/scsi/ibmmca.txt | |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
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| 1 | |||
| 2 | -=< The IBM Microchannel SCSI-Subsystem >=- | ||
| 3 | |||
| 4 | for the IBM PS/2 series | ||
| 5 | |||
| 6 | Low Level Software-Driver for Linux | ||
| 7 | |||
| 8 | Copyright (c) 1995 Strom Systems, Inc. under the terms of the GNU | ||
| 9 | General Public License. Originally written by Martin Kolinek, December 1995. | ||
| 10 | Officially modified and maintained by Michael Lang since January 1999. | ||
| 11 | |||
| 12 | Version 4.0a | ||
| 13 | |||
| 14 | Last update: January 3, 2001 | ||
| 15 | |||
| 16 | Before you Start | ||
| 17 | ---------------- | ||
| 18 | This is the common README.ibmmca file for all driver releases of the | ||
| 19 | IBM MCA SCSI driver for Linux. Please note, that driver releases 4.0 | ||
| 20 | or newer do not work with kernel versions older than 2.4.0, while driver | ||
| 21 | versions older than 4.0 do not work with kernels 2.4.0 or later! If you | ||
| 22 | try to compile your kernel with the wrong driver source, the | ||
| 23 | compilation is aborted and you get a corresponding error message. This is | ||
| 24 | no bug in the driver. It prevents you from using the wrong sourcecode | ||
| 25 | with the wrong kernel version. | ||
| 26 | |||
| 27 | Authors of this Driver | ||
| 28 | ---------------------- | ||
| 29 | - Chris Beauregard (improvement of the SCSI-device mapping by the driver) | ||
| 30 | - Martin Kolinek (origin, first release of this driver) | ||
| 31 | - Klaus Kudielka (multiple SCSI-host management/detection, adaption to | ||
| 32 | Linux Kernel 2.1.x, module support) | ||
| 33 | - Michael Lang (assigning original pun/lun mapping, dynamical ldn | ||
| 34 | assignment, rewritten adapter detection, this file, | ||
| 35 | patches, official driver maintenance and subsequent | ||
| 36 | debugging, related with the driver) | ||
| 37 | |||
| 38 | Table of Contents | ||
| 39 | ----------------- | ||
| 40 | 1 Abstract | ||
| 41 | 2 Driver Description | ||
| 42 | 2.1 IBM SCSI-Subsystem Detection | ||
| 43 | 2.2 Physical Units, Logical Units, and Logical Devices | ||
| 44 | 2.3 SCSI-Device Recognition and dynamical ldn Assignment | ||
| 45 | 2.4 SCSI-Device Order | ||
| 46 | 2.5 Regular SCSI-Command-Processing | ||
| 47 | 2.6 Abort & Reset Commands | ||
| 48 | 2.7 Disk Geometry | ||
| 49 | 2.8 Kernel Boot Option | ||
| 50 | 2.9 Driver Module Support | ||
| 51 | 2.10 Multiple Hostadapter Support | ||
| 52 | 2.11 /proc/scsi-Filesystem Information | ||
| 53 | 2.12 /proc/mca-Filesystem Information | ||
| 54 | 2.13 Supported IBM SCSI-Subsystems | ||
| 55 | 2.14 Linux Kernel Versions | ||
| 56 | 3 Code History | ||
| 57 | 4 To do | ||
| 58 | 5 Users' Manual | ||
| 59 | 5.1 Commandline Parameters | ||
| 60 | 5.2 Troubleshooting | ||
| 61 | 5.3 Bugreports | ||
| 62 | 5.4 Support WWW-page | ||
| 63 | 6 References | ||
| 64 | 7 Credits to | ||
| 65 | 7.1 People | ||
| 66 | 7.2 Sponsors & Supporters | ||
| 67 | 8 Trademarks | ||
| 68 | 9 Disclaimer | ||
| 69 | |||
| 70 | * * * | ||
| 71 | |||
| 72 | 1 Abstract | ||
| 73 | ---------- | ||
| 74 | This README-file describes the IBM SCSI-subsystem low level driver for | ||
| 75 | Linux. The descriptions which were formerly kept in the source-code have | ||
| 76 | been taken out to this file to easify the codes' readability. The driver | ||
| 77 | description has been updated, as most of the former description was already | ||
| 78 | quite outdated. The history of the driver development is also kept inside | ||
| 79 | here. Multiple historical developments have been summarized to shorten the | ||
| 80 | textsize a bit. At the end of this file you can find a small manual for | ||
| 81 | this driver and hints to get it running on your machine. | ||
| 82 | |||
| 83 | 2 Driver Description | ||
| 84 | -------------------- | ||
| 85 | 2.1 IBM SCSI-Subsystem Detection | ||
| 86 | -------------------------------- | ||
| 87 | This is done in the ibmmca_detect() function. It first checks, if the | ||
| 88 | Microchannel-bus support is enabled, as the IBM SCSI-subsystem needs the | ||
| 89 | Microchannel. In a next step, a free interrupt is chosen and the main | ||
| 90 | interrupt handler is connected to it to handle answers of the SCSI- | ||
| 91 | subsystem(s). If the F/W SCSI-adapter is forced by the BIOS to use IRQ11 | ||
| 92 | instead of IRQ14, IRQ11 is used for the IBM SCSI-2 F/W adapter. In a | ||
| 93 | further step it is checked, if the adapter gets detected by force from | ||
| 94 | the kernel commandline, where the I/O port and the SCSI-subsystem id can | ||
| 95 | be specified. The next step checks if there is an integrated SCSI-subsystem | ||
| 96 | installed. This register area is fixed through all IBM PS/2 MCA-machines | ||
| 97 | and appears as something like a virtual slot 10 of the MCA-bus. On most | ||
| 98 | PS/2 machines, the POS registers of slot 10 are set to 0xff or 0x00 if not | ||
| 99 | integrated SCSI-controller is available. But on certain PS/2s, like model | ||
| 100 | 9595, this slot 10 is used to store other information which at earlier | ||
| 101 | stage confused the driver and resulted in the detection of some ghost-SCSI. | ||
| 102 | If POS-register 2 and 3 are not 0x00 and not 0xff, but all other POS | ||
| 103 | registers are either 0xff or 0x00, there must be an integrated SCSI- | ||
| 104 | subsystem present and it will be registered as IBM Integrated SCSI- | ||
| 105 | Subsystem. The next step checks, if there is a slot-adapter installed on | ||
| 106 | the MCA-bus. To get this, the first two POS-registers, that represent the | ||
| 107 | adapter ID are checked. If they fit to one of the ids, stored in the | ||
| 108 | adapter list, a SCSI-subsystem is assumed to be found in a slot and will be | ||
| 109 | registered. This check is done through all possible MCA-bus slots to allow | ||
| 110 | more than one SCSI-adapter to be present in the PS/2-system and this is | ||
| 111 | already the first point of problems. Looking into the technical reference | ||
| 112 | manual for the IBM PS/2 common interfaces, the POS2 register must have | ||
| 113 | different interpretation of its single bits to avoid overlapping I/O | ||
| 114 | regions. While one can assume, that the integrated subsystem has a fix | ||
| 115 | I/O-address at 0x3540 - 0x3547, further installed IBM SCSI-adapters must | ||
| 116 | use a different I/O-address. This is expressed by bit 1 to 3 of POS2 | ||
| 117 | (multiplied by 8 + 0x3540). Bits 2 and 3 are reserved for the integrated | ||
| 118 | subsystem, but not for the adapters! The following list shows, how the | ||
| 119 | bits of POS2 and POS3 should be interpreted. | ||
| 120 | |||
| 121 | The POS2-register of all PS/2 models' integrated SCSI-subsystems has the | ||
| 122 | following interpretation of bits: | ||
| 123 | Bit 7 - 4 : Chip Revision ID (Release) | ||
| 124 | Bit 3 - 2 : Reserved | ||
| 125 | Bit 1 : 8k NVRAM Disabled | ||
| 126 | Bit 0 : Chip Enable (EN-Signal) | ||
| 127 | The POS3-register is interpreted as follows (for most IBM SCSI-subsys.): | ||
| 128 | Bit 7 - 5 : SCSI ID | ||
| 129 | Bit 4 - 0 : Reserved = 0 | ||
| 130 | The slot-adapters have different interpretation of these bits. The IBM SCSI | ||
| 131 | adapter (w/Cache) and the IBM SCSI-2 F/W adapter use the following | ||
| 132 | interpretation of the POS2 register: | ||
| 133 | Bit 7 - 4 : ROM Segment Address Select | ||
| 134 | Bit 3 - 1 : Adapter I/O Address Select (*8+0x3540) | ||
| 135 | Bit 0 : Adapter Enable (EN-Signal) | ||
| 136 | and for the POS3 register: | ||
| 137 | Bit 7 - 5 : SCSI ID | ||
| 138 | Bit 4 : Fairness Enable (SCSI ID3 f. F/W) | ||
| 139 | Bit 3 - 0 : Arbitration Level | ||
| 140 | The most modern product of the series is the IBM SCSI-2 F/W adapter, it | ||
| 141 | allows dual-bus SCSI and SCSI-wide addressing, which means, PUNs may be | ||
| 142 | between 0 and 15. Here, Bit 4 is the high-order bit of the 4-bit wide | ||
| 143 | adapter PUN expression. In short words, this means, that IBM PS/2 machines | ||
| 144 | can only support 1 single integrated subsystem by default. Additional | ||
| 145 | slot-adapters get ports assigned by the automatic configuration tool. | ||
| 146 | |||
| 147 | One day I found a patch in ibmmca_detect(), forcing the I/O-address to be | ||
| 148 | 0x3540 for integrated SCSI-subsystems, there was a remark placed, that on | ||
| 149 | integrated IBM SCSI-subsystems of model 56, the POS2 register was showing 5. | ||
| 150 | This means, that really for these models, POS2 has to be interpreted | ||
| 151 | sticking to the technical reference guide. In this case, the bit 2 (4) is | ||
| 152 | a reserved bit and may not be interpreted. These differences between the | ||
| 153 | adapters and the integrated controllers are taken into account by the | ||
| 154 | detection routine of the driver on from version >3.0g. | ||
| 155 | |||
| 156 | Every time, a SCSI-subsystem is discovered, the ibmmca_register() function | ||
| 157 | is called. This function checks first, if the requested area for the I/O- | ||
| 158 | address of this SCSI-subsystem is still available and assigns this I/O- | ||
| 159 | area to the SCSI-subsystem. There are always 8 sequential I/O-addresses | ||
| 160 | taken for each individual SCSI-subsystem found, which are: | ||
| 161 | |||
| 162 | Offset Type Permissions | ||
| 163 | 0 Command Interface Register 1 Read/Write | ||
| 164 | 1 Command Interface Register 2 Read/Write | ||
| 165 | 2 Command Interface Register 3 Read/Write | ||
| 166 | 3 Command Interface Register 4 Read/Write | ||
| 167 | 4 Attention Register Read/Write | ||
| 168 | 5 Basic Control Register Read/Write | ||
| 169 | 6 Interrupt Status Register Read | ||
| 170 | 7 Basic Status Register Read | ||
| 171 | |||
| 172 | After the I/O-address range is assigned, the host-adapter is assigned | ||
| 173 | to a local structure which keeps all adapter information needed for the | ||
| 174 | driver itself and the mid- and higher-level SCSI-drivers. The SCSI pun/lun | ||
| 175 | and the adapters' ldn tables are initialized and get probed afterwards by | ||
| 176 | the check_devices() function. If no further adapters are found, | ||
| 177 | ibmmca_detect() quits. | ||
| 178 | |||
| 179 | 2.2 Physical Units, Logical Units, and Logical Devices | ||
| 180 | ------------------------------------------------------ | ||
| 181 | There can be up to 56 devices on the SCSI bus (besides the adapter): | ||
| 182 | there are up to 7 "physical units" (each identified by physical unit | ||
| 183 | number or pun, also called the scsi id, this is the number you select | ||
| 184 | with hardware jumpers), and each physical unit can have up to 8 | ||
| 185 | "logical units" (each identified by logical unit number, or lun, | ||
| 186 | between 0 and 7). The IBM SCSI-2 F/W adapter offers this on up to two | ||
| 187 | busses and provides support for 30 logical devices at the same time, where | ||
| 188 | in wide-addressing mode you can have 16 puns with 32 luns on each device. | ||
| 189 | This section dexribes you the handling of devices on non-F/W adapters. | ||
| 190 | Just imagine, that you can have 16 * 32 = 512 devices on a F/W adapter | ||
| 191 | which means a lot of possible devices for such a small machine. | ||
| 192 | |||
| 193 | Typically the adapter has pun=7, so puns of other physical units | ||
| 194 | are between 0 and 6(15). On a wide-adapter a pun higher than 7 is | ||
| 195 | possible, but is normally not used. Almost all physical units have only | ||
| 196 | one logical unit, with lun=0. A CD-ROM jukebox would be an example of a | ||
| 197 | physical unit with more than one logical unit. | ||
| 198 | |||
| 199 | The embedded microprocessor of the IBM SCSI-subsystem hides the complex | ||
| 200 | two-dimensional (pun,lun) organization from the operating system. | ||
| 201 | When the machine is powered-up (or rebooted), the embedded microprocessor | ||
| 202 | checks, on its own, all 56 possible (pun,lun) combinations, and the first | ||
| 203 | 15 devices found are assigned into a one-dimensional array of so-called | ||
| 204 | "logical devices", identified by "logical device numbers" or ldn. The last | ||
| 205 | ldn=15 is reserved for the subsystem itself. Wide adapters may have | ||
| 206 | to check up to 15 * 8 = 120 pun/lun combinations. | ||
| 207 | |||
| 208 | 2.3 SCSI-Device Recognition and Dynamical ldn Assignment | ||
| 209 | -------------------------------------------------------- | ||
| 210 | One consequence of information hiding is that the real (pun,lun) | ||
| 211 | numbers are also hidden. The two possibilities to get around this problem | ||
| 212 | is to offer fake pun/lun combinations to the operating system or to | ||
| 213 | delete the whole mapping of the adapter and to reassign the ldns, using | ||
| 214 | the immediate assign command of the SCSI-subsystem for probing through | ||
| 215 | all possible pun/lun combinations. a ldn is a "logical device number" | ||
| 216 | which is used by IBM SCSI-subsystems to access some valid SCSI-device. | ||
| 217 | At the beginning of the development of this driver, the following approach | ||
| 218 | was used: | ||
| 219 | |||
| 220 | First, the driver checked the ldn's (0 to 6) to find out which ldn's | ||
| 221 | have devices assigned. This was done by the functions check_devices() and | ||
| 222 | device_exists(). The interrupt handler has a special paragraph of code | ||
| 223 | (see local_checking_phase_flag) to assist in the checking. Assume, for | ||
| 224 | example, that three logical devices were found assigned at ldn 0, 1, 2. | ||
| 225 | These are presented to the upper layer of Linux SCSI driver | ||
| 226 | as devices with bogus (pun, lun) equal to (0,0), (1,0), (2,0). | ||
| 227 | On the other hand, if the upper layer issues a command to device | ||
| 228 | say (4,0), this driver returns DID_NO_CONNECT error. | ||
| 229 | |||
| 230 | In a second step of the driver development, the following improvement has | ||
| 231 | been applied: The first approach limited the number of devices to 7, far | ||
| 232 | fewer than the 15 that it could usem then it just maped ldn -> | ||
| 233 | (ldn/8,ldn%8) for pun,lun. We ended up with a real mishmash of puns | ||
| 234 | and luns, but it all seemed to work. | ||
| 235 | |||
| 236 | The latest development, which is implemented from the driver version 3.0 | ||
| 237 | and later, realizes the device recognition in the following way: | ||
| 238 | The physical SCSI-devices on the SCSI-bus are probed via immediate_assign- | ||
| 239 | and device_inquiry-commands, that is all implemented in a completely new | ||
| 240 | made check_devices() subroutine. This delivers an exact map of the physical | ||
| 241 | SCSI-world that is now stored in the get_scsi[][]-array. This means, | ||
| 242 | that the once hidden pun,lun assignment is now known to this driver. | ||
| 243 | It no longer believes in default-settings of the subsystem and maps all | ||
| 244 | ldns to existing pun,lun "by foot". This assures full control of the ldn | ||
| 245 | mapping and allows dynamical remapping of ldns to different pun,lun, if | ||
| 246 | there are more SCSI-devices installed than ldns available (n>15). The | ||
| 247 | ldns from 0 to 6 get 'hardwired' by this driver to puns 0 to 7 at lun=0, | ||
| 248 | excluding the pun of the subsystem. This assures, that at least simple | ||
| 249 | SCSI-installations have optimum access-speed and are not touched by | ||
| 250 | dynamical remapping. The ldns 7 to 14 are put to existing devices with | ||
| 251 | lun>0 or to non-existing devices, in order to satisfy the subsystem, if | ||
| 252 | there are less than 15 SCSI-devices connected. In the case of more than 15 | ||
| 253 | devices, the dynamical mapping goes active. If the get_scsi[][] reports a | ||
| 254 | device to be existant, but it has no ldn assigned, it gets a ldn out of 7 | ||
| 255 | to 14. The numbers are assigned in cyclic order. Therefore it takes 8 | ||
| 256 | dynamical reassignments on the SCSI-devices, until a certain device | ||
| 257 | loses its ldn again. This assures, that dynamical remapping is avoided | ||
| 258 | during intense I/O between up to 15 SCSI-devices (means pun,lun | ||
| 259 | combinations). A further advantage of this method is, that people who | ||
| 260 | build their kernel without probing on all luns will get what they expect, | ||
| 261 | because the driver just won't assign everything with lun>0 when | ||
| 262 | multpile lun probing is inactive. | ||
| 263 | |||
| 264 | 2.4 SCSI-Device Order | ||
| 265 | --------------------- | ||
| 266 | Because of the now correct recognition of physical pun,lun, and | ||
| 267 | their report to mid-level- and higher-level-drivers, the new reported puns | ||
| 268 | can be different from the old, faked puns. Therefore, Linux will eventually | ||
| 269 | change /dev/sdXXX assignments and prompt you for corrupted superblock | ||
| 270 | repair on boottime. In this case DO NOT PANIC, YOUR DISKS ARE STILL OK!!! | ||
| 271 | You have to reboot (CTRL-D) with an old kernel and set the /etc/fstab-file | ||
| 272 | entries right. After that, the system should come up as errorfree as before. | ||
| 273 | If your boot-partition is not coming up, also edit the /etc/lilo.conf-file | ||
| 274 | in a Linux session booted on old kernel and run lilo before reboot. Check | ||
| 275 | lilo.conf anyway to get boot on other partitions with foreign OSes right | ||
| 276 | again. But there exists a feature of this driver that allows you to change | ||
| 277 | the assignment order of the SCSI-devices by flipping the PUN-assignment. | ||
| 278 | See the next paragraph for a description. | ||
| 279 | |||
| 280 | The problem for this is, that Linux does not assign the SCSI-devices in the | ||
| 281 | way as described in the ANSI-SCSI-standard. Linux assigns /dev/sda to | ||
| 282 | the device with at minimum id 0. But the first drive should be at id 6, | ||
| 283 | because for historical reasons, drive at id 6 has, by hardware, the highest | ||
| 284 | priority and a drive at id 0 the lowest. IBM was one of the rare producers, | ||
| 285 | where the BIOS assigns drives belonging to the ANSI-SCSI-standard. Most | ||
| 286 | other producers' BIOS does not (I think even Adaptec-BIOS). The | ||
| 287 | IBMMCA_SCSI_ORDER_STANDARD flag, which you set while configuring the | ||
| 288 | kernel enables to choose the preferred way of SCSI-device-assignment. | ||
| 289 | Defining this flag would result in Linux determining the devices in the | ||
| 290 | same order as DOS and OS/2 does on your MCA-machine. This is also standard | ||
| 291 | on most industrial computers and OSes, like e.g. OS-9. Leaving this flag | ||
| 292 | undefined will get your devices ordered in the default way of Linux. See | ||
| 293 | also the remarks of Chris Beauregard from Dec 15, 1997 and the followups | ||
| 294 | in section 3. | ||
| 295 | |||
| 296 | 2.5 Regular SCSI-Command-Processing | ||
| 297 | ----------------------------------- | ||
| 298 | Only three functions get involved: ibmmca_queuecommand(), issue_cmd(), | ||
| 299 | and interrupt_handler(). | ||
| 300 | |||
| 301 | The upper layer issues a scsi command by calling function | ||
| 302 | ibmmca_queuecommand(). This function fills a "subsystem control block" | ||
| 303 | (scb) and calls a local function issue_cmd(), which writes a scb | ||
| 304 | command into subsystem I/O ports. Once the scb command is carried out, | ||
| 305 | the interrupt_handler() is invoked. If a device is determined to be | ||
| 306 | existant and it has not assigned any ldn, it gets one dynamically. | ||
| 307 | For this, the whole stuff is done in ibmmca_queuecommand(). | ||
| 308 | |||
| 309 | 2.6 Abort & Reset Commands | ||
| 310 | -------------------------- | ||
| 311 | These are implemented with busy waiting for interrupt to arrive. | ||
| 312 | ibmmca_reset() and ibmmca_abort() do not work sufficently well | ||
| 313 | up to now and need still a lot of development work. But, this seems | ||
| 314 | to be even a problem with other SCSI-low level drivers, too. However, | ||
| 315 | this should be no excuse. | ||
| 316 | |||
| 317 | 2.7 Disk Geometry | ||
| 318 | ----------------- | ||
| 319 | The ibmmca_biosparams() function should return the same disk geometry | ||
| 320 | as the bios. This is needed for fdisk, etc. The returned geometry is | ||
| 321 | certainly correct for disks smaller than 1 gigabyte. In the meantime, | ||
| 322 | it has been proved, that this works fine even with disks larger than | ||
| 323 | 1 gigabyte. | ||
| 324 | |||
| 325 | 2.8 Kernel Boot Option | ||
| 326 | ---------------------- | ||
| 327 | The function ibmmca_scsi_setup() is called if option ibmmcascsi=n | ||
| 328 | is passed to the kernel. See file linux/init/main.c for details. | ||
| 329 | |||
| 330 | 2.9 Driver Module Support | ||
| 331 | ------------------------- | ||
| 332 | Is implemented and tested by K. Kudielka. This could probably not work | ||
| 333 | on kernels <2.1.0. | ||
| 334 | |||
| 335 | 2.10 Multiple Hostadapter Support | ||
| 336 | --------------------------------- | ||
| 337 | This driver supports up to eight interfaces of type IBM-SCSI-Subsystem. | ||
| 338 | Integrated-, and MCA-adapters are automatically recognized. Unrecognizable | ||
| 339 | IBM-SCSI-Subsystem interfaces can be specified as kernel-parameters. | ||
| 340 | |||
| 341 | 2.11 /proc/scsi-Filesystem Information | ||
| 342 | -------------------------------------- | ||
| 343 | Information about the driver condition is given in | ||
| 344 | /proc/scsi/ibmmca/<host_no>. ibmmca_proc_info() provides this information. | ||
| 345 | |||
| 346 | This table is quite informative for interested users. It shows the load | ||
| 347 | of commands on the subsystem and wether you are running the bypassed | ||
| 348 | (software) or integrated (hardware) SCSI-command set (see below). The | ||
| 349 | amount of accesses is shown. Read, write, modeselect is shown separately | ||
| 350 | in order to help debugging problems with CD-ROMs or tapedrives. | ||
| 351 | |||
| 352 | The following table shows the list of 15 logical device numbers, that are | ||
| 353 | used by the SCSI-subsystem. The load on each ldn is shown in the table, | ||
| 354 | again, read and write commands are split. The last column shows the amount | ||
| 355 | of reassignments, that have been applied to the ldns, if you have more than | ||
| 356 | 15 pun/lun combinations available on the SCSI-bus. | ||
| 357 | |||
| 358 | The last two tables show the pun/lun map and the positions of the ldns | ||
| 359 | on this pun/lun map. This may change during operation, when a ldn is | ||
| 360 | reassigned to another pun/lun combination. If the necessity for dynamical | ||
| 361 | assignments is set to 'no', the ldn structure keeps static. | ||
| 362 | |||
| 363 | 2.12 /proc/mca-Filesystem Information | ||
| 364 | ------------------------------------- | ||
| 365 | The slot-file contains all default entries and in addition chip and I/O- | ||
| 366 | address information of the SCSI-subsystem. This information is provided | ||
| 367 | by ibmmca_getinfo(). | ||
| 368 | |||
| 369 | 2.13 Supported IBM SCSI-Subsystems | ||
| 370 | ---------------------------------- | ||
| 371 | The following IBM SCSI-subsystems are supported by this driver: | ||
| 372 | |||
| 373 | - IBM Fast/Wide SCSI-2 Adapter | ||
| 374 | - IBM 7568 Industrial Computer SCSI Adapter w/Cache | ||
| 375 | - IBM Expansion Unit SCSI Controller | ||
| 376 | - IBM SCSI Adapter w/Cache | ||
| 377 | - IBM SCSI Adapter | ||
| 378 | - IBM Integrated SCSI Controller | ||
| 379 | - All clones, 100% compatible with the chipset and subsystem command | ||
| 380 | system of IBM SCSI-adapters (forced detection) | ||
| 381 | |||
| 382 | 2.14 Linux Kernel Versions | ||
| 383 | -------------------------- | ||
| 384 | The IBM SCSI-subsystem low level driver is prepared to be used with | ||
| 385 | all versions of Linux between 2.0.x and 2.4.x. The compatibility checks | ||
| 386 | are fully implemented up from version 3.1e of the driver. This means, that | ||
| 387 | you just need the latest ibmmca.h and ibmmca.c file and copy it in the | ||
| 388 | linux/drivers/scsi directory. The code is automatically adapted during | ||
| 389 | kernel compilation. This is different from kernel 2.4.0! Here version | ||
| 390 | 4.0 or later of the driver must be used for kernel 2.4.0 or later. Version | ||
| 391 | 4.0 or later does not work together with older kernels! Driver versions | ||
| 392 | older than 4.0 do not work together with kernel 2.4.0 or later. They work | ||
| 393 | on all older kernels. | ||
| 394 | |||
| 395 | 3 Code History | ||
| 396 | -------------- | ||
| 397 | Jan 15 1996: First public release. | ||
| 398 | - Martin Kolinek | ||
| 399 | |||
| 400 | Jan 23 1996: Scrapped code which reassigned scsi devices to logical | ||
| 401 | device numbers. Instead, the existing assignment (created | ||
| 402 | when the machine is powered-up or rebooted) is used. | ||
| 403 | A side effect is that the upper layer of Linux SCSI | ||
| 404 | device driver gets bogus scsi ids (this is benign), | ||
| 405 | and also the hard disks are ordered under Linux the | ||
| 406 | same way as they are under dos (i.e., C: disk is sda, | ||
| 407 | D: disk is sdb, etc.). | ||
| 408 | - Martin Kolinek | ||
| 409 | |||
| 410 | I think that the CD-ROM is now detected only if a CD is | ||
| 411 | inside CD_ROM while Linux boots. This can be fixed later, | ||
| 412 | once the driver works on all types of PS/2's. | ||
| 413 | - Martin Kolinek | ||
| 414 | |||
| 415 | Feb 7 1996: Modified biosparam function. Fixed the CD-ROM detection. | ||
| 416 | For now, devices other than harddisk and CD_ROM are | ||
| 417 | ignored. Temporarily modified abort() function | ||
| 418 | to behave like reset(). | ||
| 419 | - Martin Kolinek | ||
| 420 | |||
| 421 | Mar 31 1996: The integrated scsi subsystem is correctly found | ||
| 422 | in PS/2 models 56,57, but not in model 76. Therefore | ||
| 423 | the ibmmca_scsi_setup() function has been added today. | ||
| 424 | This function allows the user to force detection of | ||
| 425 | scsi subsystem. The kernel option has format | ||
| 426 | ibmmcascsi=n | ||
| 427 | where n is the scsi_id (pun) of the subsystem. Most likely, n is 7. | ||
| 428 | - Martin Kolinek | ||
| 429 | |||
| 430 | Aug 21 1996: Modified the code which maps ldns to (pun,0). It was | ||
| 431 | insufficient for those of us with CD-ROM changers. | ||
| 432 | - Chris Beauregard | ||
| 433 | |||
| 434 | Dec 14 1996: More improvements to the ldn mapping. See check_devices | ||
| 435 | for details. Did more fiddling with the integrated SCSI detection, | ||
| 436 | but I think it's ultimately hopeless without actually testing the | ||
| 437 | model of the machine. The 56, 57, 76 and 95 (ultimedia) all have | ||
| 438 | different integrated SCSI register configurations. However, the 56 | ||
| 439 | and 57 are the only ones that have problems with forced detection. | ||
| 440 | - Chris Beauregard | ||
| 441 | |||
| 442 | Mar 8-16 1997: Modified driver to run as a module and to support | ||
| 443 | multiple adapters. A structure, called ibmmca_hostdata, is now | ||
| 444 | present, containing all the variables, that were once only | ||
| 445 | available for one single adapter. The find_subsystem-routine has vanished. | ||
| 446 | The hardware recognition is now done in ibmmca_detect directly. | ||
| 447 | This routine checks for presence of MCA-bus, checks the interrupt | ||
| 448 | level and continues with checking the installed hardware. | ||
| 449 | Certain PS/2-models do not recognize a SCSI-subsystem automatically. | ||
| 450 | Hence, the setup defined by command-line-parameters is checked first. | ||
| 451 | Thereafter, the routine probes for an integrated SCSI-subsystem. | ||
| 452 | Finally, adapters are checked. This method has the advantage to cover all | ||
| 453 | possible combinations of multiple SCSI-subsystems on one MCA-board. Up to | ||
| 454 | eight SCSI-subsystems can be recognized and announced to the upper-level | ||
| 455 | drivers with this improvement. A set of defines made changes to other | ||
| 456 | routines as small as possible. | ||
| 457 | - Klaus Kudielka | ||
| 458 | |||
| 459 | May 30 1997: (v1.5b) | ||
| 460 | 1) SCSI-command capability enlarged by the recognition of MODE_SELECT. | ||
| 461 | This needs the RD-Bit to be disabled on IM_OTHER_SCSI_CMD_CMD which | ||
| 462 | allows data to be written from the system to the device. It is a | ||
| 463 | necessary step to be allowed to set blocksize of SCSI-tape-drives and | ||
| 464 | the tape-speed, whithout confusing the SCSI-Subsystem. | ||
| 465 | 2) The recognition of a tape is included in the check_devices routine. | ||
| 466 | This is done by checking for TYPE_TAPE, that is already defined in | ||
| 467 | the kernel-scsi-environment. The markup of a tape is done in the | ||
| 468 | global ldn_is_tape[] array. If the entry on index ldn | ||
| 469 | is 1, there is a tapedrive connected. | ||
| 470 | 3) The ldn_is_tape[] array is necessary to distinguish between tape- and | ||
| 471 | other devices. Fixed blocklength devices should not cause a problem | ||
| 472 | with the SCB-command for read and write in the ibmmca_queuecommand | ||
| 473 | subroutine. Therefore, I only derivate the READ_XX, WRITE_XX for | ||
| 474 | the tape-devices, as recommended by IBM in this Technical Reference, | ||
| 475 | mentioned below. (IBM recommends to avoid using the read/write of the | ||
| 476 | subsystem, but the fact was, that read/write causes a command error from | ||
| 477 | the subsystem and this causes kernel-panic.) | ||
| 478 | 4) In addition, I propose to use the ldn instead of a fix char for the | ||
| 479 | display of PS2_DISK_LED_ON(). On 95, one can distinguish between the | ||
| 480 | devices that are accessed. It shows activity and easyfies debugging. | ||
| 481 | The tape-support has been tested with a SONY SDT-5200 and a HP DDS-2 | ||
| 482 | (I do not know yet the type). Optimization and CD-ROM audio-support, | ||
| 483 | I am working on ... | ||
| 484 | - Michael Lang | ||
| 485 | |||
| 486 | June 19 1997: (v1.6b) | ||
| 487 | 1) Submitting the extra-array ldn_is_tape[] -> to the local ld[] | ||
| 488 | device-array. | ||
| 489 | 2) CD-ROM Audio-Play seems to work now. | ||
| 490 | 3) When using DDS-2 (120M) DAT-Tapes, mtst shows still density-code | ||
| 491 | 0x13 for ordinary DDS (61000 BPM) instead 0x24 for DDS-2. This appears | ||
| 492 | also on Adaptec 2940 adaptor in a PCI-System. Therefore, I assume that | ||
| 493 | the problem is independent of the low-level-driver/bus-architecture. | ||
| 494 | 4) Hexadecimal ldn on PS/2-95 LED-display. | ||
| 495 | 5) Fixing of the PS/2-LED on/off that it works right with tapedrives and | ||
| 496 | does not confuse the disk_rw_in_progress counter. | ||
| 497 | - Michael Lang | ||
| 498 | |||
| 499 | June 21 1997: (v1.7b) | ||
| 500 | 1) Adding of a proc_info routine to inform in /proc/scsi/ibmmca/<host> the | ||
| 501 | outer-world about operational load statistics on the different ldns, | ||
| 502 | seen by the driver. Everybody that has more than one IBM-SCSI should | ||
| 503 | test this, because I only have one and cannot see what happens with more | ||
| 504 | than one IBM-SCSI hosts. | ||
| 505 | 2) Definition of a driver version-number to have a better recognition of | ||
| 506 | the source when there are existing too much releases that may confuse | ||
| 507 | the user, when reading about release-specific problems. Up to know, | ||
| 508 | I calculated the version-number to be 1.7. Because we are in BETA-test | ||
| 509 | yet, it is today 1.7b. | ||
| 510 | 3) Sorry for the heavy bug I programmed on June 19 1997! After that, the | ||
| 511 | CD-ROM did not work any more! The C7-command was a fake impression | ||
| 512 | I got while programming. Now, the READ and WRITE commands for CD-ROM are | ||
| 513 | no longer running over the subsystem, but just over | ||
| 514 | IM_OTHER_SCSI_CMD_CMD. On my observations (PS/2-95), now CD-ROM mounts | ||
| 515 | much faster(!) and hopefully all fancy multimedia-functions, like direct | ||
| 516 | digital recording from audio-CDs also work. (I tried it with cdda2wav | ||
| 517 | from the cdwtools-package and it filled up the harddisk immediately :-).) | ||
| 518 | To easify boolean logics, a further local device-type in ld[], called | ||
| 519 | is_cdrom has been included. | ||
| 520 | 4) If one uses a SCSI-device of unsupported type/commands, one | ||
| 521 | immediately runs into a kernel-panic caused by Command Error. To better | ||
| 522 | understand which SCSI-command caused the problem, I extended this | ||
| 523 | specific panic-message slightly. | ||
| 524 | - Michael Lang | ||
| 525 | |||
| 526 | June 25 1997: (v1.8b) | ||
| 527 | 1) Some cosmetical changes for the handling of SCSI-device-types. | ||
| 528 | Now, also CD-Burners / WORMs and SCSI-scanners should work. For | ||
| 529 | MO-drives I have no experience, therefore not yet supported. | ||
| 530 | In logical_devices I changed from different type-variables to one | ||
| 531 | called 'device_type' where the values, corresponding to scsi.h, | ||
| 532 | of a SCSI-device are stored. | ||
| 533 | 2) There existed a small bug, that maps a device, coming after a SCSI-tape | ||
| 534 | wrong. Therefore, e.g. a CD-ROM changer would have been mapped wrong | ||
| 535 | -> problem removed. | ||
| 536 | 3) Extension of the logical_device structure. Now it contains also device, | ||
| 537 | vendor and revision-level of a SCSI-device for internal usage. | ||
| 538 | - Michael Lang | ||
| 539 | |||
| 540 | June 26-29 1997: (v2.0b) | ||
| 541 | 1) The release number 2.0b is necessary because of the completely new done | ||
| 542 | recognition and handling of SCSI-devices with the adapter. As I got | ||
| 543 | from Chris the hint, that the subsystem can reassign ldns dynamically, | ||
| 544 | I remembered this immediate_assign-command, I found once in the handbook. | ||
| 545 | Now, the driver first kills all ldn assignments that are set by default | ||
| 546 | on the SCSI-subsystem. After that, it probes on all puns and luns for | ||
| 547 | devices by going through all combinations with immediate_assign and | ||
| 548 | probing for devices, using device_inquiry. The found physical(!) pun,lun | ||
| 549 | structure is stored in get_scsi[][] as device types. This is followed | ||
| 550 | by the assignment of all ldns to existing SCSI-devices. If more ldns | ||
| 551 | than devices are available, they are assigned to non existing pun,lun | ||
| 552 | combinations to satisfy the adapter. With this, the dynamical mapping | ||
| 553 | was possible to implement. (For further info see the text in the | ||
| 554 | source-code and in the description below. Read the description | ||
| 555 | below BEFORE installing this driver on your system!) | ||
| 556 | 2) Changed the name IBMMCA_DRIVER_VERSION to IBMMCA_SCSI_DRIVER_VERSION. | ||
| 557 | 3) The LED-display shows on PS/2-95 no longer the ldn, but the SCSI-ID | ||
| 558 | (pun) of the accessed SCSI-device. This is now senseful, because the | ||
| 559 | pun known within the driver is exactly the pun of the physical device | ||
| 560 | and no longer a fake one. | ||
| 561 | 4) The /proc/scsi/ibmmca/<host_no> consists now of the first part, where | ||
| 562 | hit-statistics of ldns is shown and a second part, where the maps of | ||
| 563 | physical and logical SCSI-devices are displayed. This could be very | ||
| 564 | interesting, when one is using more than 15 SCSI-devices in order to | ||
| 565 | follow the dynamical remapping of ldns. | ||
| 566 | - Michael Lang | ||
| 567 | |||
| 568 | June 26-29 1997: (v2.0b-1) | ||
| 569 | 1) I forgot to switch the local_checking_phase_flag to 1 and back to 0 | ||
| 570 | in the dynamical remapping part in ibmmca_queuecommand for the | ||
| 571 | device_exist routine. Sorry. | ||
| 572 | - Michael Lang | ||
| 573 | |||
| 574 | July 1-13 1997: (v3.0b,c) | ||
| 575 | 1) Merging of the driver-developments of Klaus Kudielka and Michael Lang | ||
| 576 | in order to get a optimum and unified driver-release for the | ||
| 577 | IBM-SCSI-Subsystem-Adapter(s). | ||
| 578 | For people, using the Kernel-release >=2.1.0, module-support should | ||
| 579 | be no problem. For users, running under <2.1.0, module-support may not | ||
| 580 | work, because the methods have changed between 2.0.x and 2.1.x. | ||
| 581 | 2) Added some more effective statistics for /proc-output. | ||
| 582 | 3) Change typecasting at necessary points from (unsigned long) to | ||
| 583 | virt_to_bus(). | ||
| 584 | 4) Included #if... at special points to have specific adaption of the | ||
| 585 | driver to kernel 2.0.x and 2.1.x. It should therefore also run with | ||
| 586 | later releases. | ||
| 587 | 5) Magneto-Optical drives and medium-changers are also recognized, now. | ||
| 588 | Therefore, we have a completely gapfree recognition of all SCSI- | ||
| 589 | device-types, that are known by Linux up to kernel 2.1.31. | ||
| 590 | 6) The flag SCSI_IBMMCA_DEV_RESET has been inserted. If it is set within | ||
| 591 | the configuration, each connected SCSI-device will get a reset command | ||
| 592 | during boottime. This can be necessary for some special SCSI-devices. | ||
| 593 | This flag should be included in Config.in. | ||
| 594 | (See also the new Config.in file.) | ||
| 595 | Probable next improvement: bad disk handler. | ||
| 596 | - Michael Lang | ||
| 597 | |||
| 598 | Sept 14 1997: (v3.0c) | ||
| 599 | 1) Some debugging and speed optimization applied. | ||
| 600 | - Michael Lang | ||
| 601 | |||
| 602 | Dec 15, 1997 | ||
| 603 | - chrisb@truespectra.com | ||
| 604 | - made the front panel display thingy optional, specified from the | ||
| 605 | command-line via ibmmcascsi=display. Along the lines of the /LED | ||
| 606 | option for the OS/2 driver. | ||
| 607 | - fixed small bug in the LED display that would hang some machines. | ||
| 608 | - reversed ordering of the drives (using the | ||
| 609 | IBMMCA_SCSI_ORDER_STANDARD define). This is necessary for two main | ||
| 610 | reasons: | ||
| 611 | - users who've already installed Linux won't be screwed. Keep | ||
| 612 | in mind that not everyone is a kernel hacker. | ||
| 613 | - be consistent with the BIOS ordering of the drives. In the | ||
| 614 | BIOS, id 6 is C:, id 0 might be D:. With this scheme, they'd be | ||
| 615 | backwards. This confuses the crap out of those heathens who've | ||
| 616 | got a impure Linux installation (which, <wince>, I'm one of). | ||
| 617 | This whole problem arises because IBM is actually non-standard with | ||
| 618 | the id to BIOS mappings. You'll find, in fdomain.c, a similar | ||
| 619 | comment about a few FD BIOS revisions. The Linux (and apparently | ||
| 620 | industry) standard is that C: maps to scsi id (0,0). Let's stick | ||
| 621 | with that standard. | ||
| 622 | - Since this is technically a branch of my own, I changed the | ||
| 623 | version number to 3.0e-cpb. | ||
| 624 | |||
| 625 | Jan 17, 1998: (v3.0f) | ||
| 626 | 1) Addition of some statistical info for /proc in proc_info. | ||
| 627 | 2) Taking care of the SCSI-assignment problem, dealed by Chris at Dec 15 | ||
| 628 | 1997. In fact, IBM is right, concerning the assignment of SCSI-devices | ||
| 629 | to driveletters. It is conform to the ANSI-definition of the SCSI- | ||
| 630 | standard to assign drive C: to SCSI-id 6, because it is the highest | ||
| 631 | hardware priority after the hostadapter (that has still today by | ||
| 632 | default everywhere id 7). Also realtime-operating systems that I use, | ||
| 633 | like LynxOS and OS9, which are quite industrial systems use top-down | ||
| 634 | numbering of the harddisks, that is also starting at id 6. Now, one | ||
| 635 | sits a bit between two chairs. On one hand side, using the define | ||
| 636 | IBMMCA_SCSI_ORDER_STANDARD makes Linux assigning disks conform to | ||
| 637 | the IBM- and ANSI-SCSI-standard and keeps this driver downward | ||
| 638 | compatible to older releases, on the other hand side, people is quite | ||
| 639 | habituated in believing that C: is assigned to (0,0) and much other | ||
| 640 | SCSI-BIOS do so. Therefore, I moved the IBMMCA_SCSI_ORDER_STANDARD | ||
| 641 | define out of the driver and put it into Config.in as subitem of | ||
| 642 | 'IBM SCSI support'. A help, added to Documentation/Configure.help | ||
| 643 | explains the differences between saying 'y' or 'n' to the user, when | ||
| 644 | IBMMCA_SCSI_ORDER_STANDARD prompts, so the ordinary user is enabled to | ||
| 645 | choose the way of assignment, depending on his own situation and gusto. | ||
| 646 | 3) Adapted SCSI_IBMMCA_DEV_RESET to the local naming convention, so it is | ||
| 647 | now called IBMMCA_SCSI_DEV_RESET. | ||
| 648 | 4) Optimization of proc_info and its subroutines. | ||
| 649 | 5) Added more in-source-comments and extended the driver description by | ||
| 650 | some explanation about the SCSI-device-assignment problem. | ||
| 651 | - Michael Lang | ||
| 652 | |||
| 653 | Jan 18, 1998: (v3.0g) | ||
| 654 | 1) Correcting names to be absolutely conform to the later 2.1.x releases. | ||
| 655 | This is necessary for | ||
| 656 | IBMMCA_SCSI_DEV_RESET -> CONFIG_IBMMCA_SCSI_DEV_RESET | ||
| 657 | IBMMCA_SCSI_ORDER_STANDARD -> CONFIG_IBMMCA_SCSI_ORDER_STANDARD | ||
| 658 | - Michael Lang | ||
| 659 | |||
| 660 | Jan 18, 1999: (v3.1 MCA-team internal) | ||
| 661 | 1) The multiple hosts structure is accessed from every subroutine, so there | ||
| 662 | is no longer the address of the device structure passed from function | ||
| 663 | to function, but only the hostindex. A call by value, nothing more. This | ||
| 664 | should really be understood by the compiler and the subsystem should get | ||
| 665 | the right values and addresses. | ||
| 666 | 2) The SCSI-subsystem detection was not complete and quite hugely buggy up | ||
| 667 | to now, compared to the technical manual. The interpretation of the pos2 | ||
| 668 | register is not as assumed by people before, therefore, I dropped a note | ||
| 669 | in the ibmmca_detect function to show the registers' interpretation. | ||
| 670 | The pos-registers of integrated SCSI-subsystems do not contain any | ||
| 671 | information concerning the IO-port offset, really. Instead, they contain | ||
| 672 | some info about the adapter, the chip, the NVRAM .... The I/O-port is | ||
| 673 | fixed to 0x3540 - 0x3547. There can be more than one adapters in the | ||
| 674 | slots and they get an offset for the I/O area in order to get their own | ||
| 675 | I/O-address area. See chapter 2 for detailed description. At least, the | ||
| 676 | detection should now work right, even on models other than 95. The 95ers | ||
| 677 | came happily around the bug, as their pos2 register contains always 0 | ||
| 678 | in the critical area. Reserved bits are not allowed to be interpreted, | ||
| 679 | therefore, IBM is allowed to set those bits as they like and they may | ||
| 680 | really vary between different PS/2 models. So, now, no interpretation | ||
| 681 | of reserved bits - hopefully no trouble here anymore. | ||
| 682 | 3) The command error, which you may get on models 55, 56, 57, 70, 77 and | ||
| 683 | P70 may have been caused by the fact, that adapters of older design do | ||
| 684 | not like sending commands to non-existing SCSI-devices and will react | ||
| 685 | with a command error as a sign of protest. While this error is not | ||
| 686 | present on IBM SCSI Adapter w/cache, it appears on IBM Integrated SCSI | ||
| 687 | Adapters. Therefore, I implemented a workarround to forgive those | ||
| 688 | adapters their protests, but it is marked up in the statisctis, so | ||
| 689 | after a successful boot, you can see in /proc/scsi/ibmmca/<host_number> | ||
| 690 | how often the command errors have been forgiven to the SCSI-subsystem. | ||
| 691 | If the number is bigger than 0, you have a SCSI subsystem of older | ||
| 692 | design, what should no longer matter. | ||
| 693 | 4) ibmmca_getinfo() has been adapted very carefully, so it shows in the | ||
| 694 | slotn file really, what is senseful to be presented. | ||
| 695 | 5) ibmmca_register() has been extended in its parameter list in order to | ||
| 696 | pass the right name of the SCSI-adapter to Linux. | ||
| 697 | - Michael Lang | ||
| 698 | |||
| 699 | Feb 6, 1999: (v3.1) | ||
| 700 | 1) Finally, after some 3.1Beta-releases, the 3.1 release. Sorry, for | ||
| 701 | the delayed release, but it was not finished with the release of | ||
| 702 | Kernel 2.2.0. | ||
| 703 | - Michael Lang | ||
| 704 | |||
| 705 | Feb 10, 1999 (v3.1) | ||
| 706 | 1) Added a new commandline parameter called 'bypass' in order to bypass | ||
| 707 | every integrated subsystem SCSI-command consequently in case of | ||
| 708 | troubles. | ||
| 709 | 2) Concatenated read_capacity requests to the harddisks. It gave a lot | ||
| 710 | of troubles with some controllers and after I wanted to apply some | ||
| 711 | extensions, it jumped out in the same situation, on my w/cache, as like | ||
| 712 | on D. Weinehalls' Model 56, having integrated SCSI. This gave me the | ||
| 713 | descissive hint to move the code-part out and declare it global. Now, | ||
| 714 | it seems to work by far much better an more stable. Let us see, what | ||
| 715 | the world thinks of it... | ||
| 716 | 3) By the way, only Sony DAT-drives seem to show density code 0x13. A | ||
| 717 | test with a HP drive gave right results, so the problem is vendor- | ||
| 718 | specific and not a problem of the OS or the driver. | ||
| 719 | - Michael Lang | ||
| 720 | |||
| 721 | Feb 18, 1999 (v3.1d) | ||
| 722 | 1) The abort command and the reset function have been checked for | ||
| 723 | inconsistencies. From the logical point of thinking, they work | ||
| 724 | at their optimum, now, but as the subsystem does not answer with an | ||
| 725 | interrupt, abort never finishes, sigh... | ||
| 726 | 2) Everything, that is accessed by a busmaster request from the adapter | ||
| 727 | is now declared as global variable, even the return-buffer in the | ||
| 728 | local checking phase. This assures, that no accesses to undefined memory | ||
| 729 | areas are performed. | ||
| 730 | 3) In ibmmca.h, the line unchecked_isa_dma is added with 1 in order to | ||
| 731 | avoid memory-pointers for the areas higher than 16MByte in order to | ||
| 732 | be sure, it also works on 16-Bit Microchannel bus systems. | ||
| 733 | 4) A lot of small things have been found, but nothing that endangered the | ||
| 734 | driver operations. Just it should be more stable, now. | ||
| 735 | - Michael Lang | ||
| 736 | |||
| 737 | Feb 20, 1999 (v3.1e) | ||
| 738 | 1) I took the warning from the Linux Kernel Hackers Guide serious and | ||
| 739 | checked the cmd->result return value to the done-function very carefully. | ||
| 740 | It is obvious, that the IBM SCSI only delivers the tsb.dev_status, if | ||
| 741 | some error appeared, else it is undefined. Now, this is fixed. Before | ||
| 742 | any SCB command gets queued, the tsb.dev_status is set to 0, so the | ||
| 743 | cmd->result won't screw up Linux higher level drivers. | ||
| 744 | 2) The reset-function has slightly improved. This is still planed for | ||
| 745 | abort. During the abort and the reset function, no interrupts are | ||
| 746 | allowed. This is however quite hard to cope with, so the INT-status | ||
| 747 | register is read. When the interrupt gets queued, one can find its | ||
| 748 | status immediately on that register and is enabled to continue in the | ||
| 749 | reset function. I had no chance to test this really, only in a bogus | ||
| 750 | situation, I got this function running, but the situation was too much | ||
| 751 | worse for Linux :-(, so tests will continue. | ||
| 752 | 3) Buffers got now consistent. No open address mapping, as before and | ||
| 753 | therefore no further troubles with the unassigned memory segmentation | ||
| 754 | faults that scrambled probes on 95XX series and even on 85XX series, | ||
| 755 | when the kernel is done in a not so perfectly fitting way. | ||
| 756 | 4) Spontaneous interrupts from the subsystem, appearing without any | ||
| 757 | command previously queued are answered with a DID_BAD_INTR result. | ||
| 758 | 5) Taken into account ZP Gus' proposals to reverse the SCSI-device | ||
| 759 | scan order. As it does not work on Kernel 2.1.x or 2.2.x, as proposed | ||
| 760 | by him, I implemented it in a slightly derived way, which offers in | ||
| 761 | addition more flexibility. | ||
| 762 | - Michael Lang | ||
| 763 | |||
| 764 | Apr 23, 2000 (v3.2pre1) | ||
| 765 | 1) During a very long time, I collected a huge amount of bugreports from | ||
| 766 | various people, trying really quite different things on their SCSI- | ||
| 767 | PS/2s. Today, all these bugreports are taken into account and should be | ||
| 768 | mostly solved. The major topics were: | ||
| 769 | - Driver crashes during boottime by no obvious reason. | ||
| 770 | - Driver panics while the midlevel-SCSI-driver is trying to inquire | ||
| 771 | the SCSI-device properties, even though hardware is in perfect state. | ||
| 772 | - Displayed info for the various slot-cards is interpreted wrong. | ||
| 773 | The main reasons for the crashes were two: | ||
| 774 | 1) The commands to check for device information like INQUIRY, | ||
| 775 | TEST_UNIT_READY, REQUEST_SENSE and MODE_SENSE cause the devices | ||
| 776 | to deliver information of up to 255 bytes. Midlevel drivers offer | ||
| 777 | 1024 bytes of space for the answer, but the IBM-SCSI-adapters do | ||
| 778 | not accept this, as they stick quite near to ANSI-SCSI and report | ||
| 779 | a COMMAND_ERROR message which causes the driver to panic. The main | ||
| 780 | problem was located around the INQUIRY command. Now, for all the | ||
| 781 | mentioned commands, the buffersize, sent to the adapter is at | ||
| 782 | maximum 255 which seems to be a quite reasonable solution. | ||
| 783 | TEST_UNIT_READY gets a buffersize of 0 to make sure, that no | ||
| 784 | data is transferred in order to avoid any possible command failure. | ||
| 785 | 2) On unsuccessful TEST_UNIT_READY, the midlevel-driver has to send | ||
| 786 | a REQUEST_SENSE in order to see, where the problem is located. This | ||
| 787 | REQUEST_SENSE may have various length in its answer-buffer. IBM | ||
| 788 | SCSI-subsystems report a command failure, if the returned buffersize | ||
| 789 | is different from the sent buffersize, but this can be supressed by | ||
| 790 | a special bit, which is now done and problems seem to be solved. | ||
| 791 | 2) Code adaption to all kernel-releases. Now, the 3.2 code compiles on | ||
| 792 | 2.0.x, 2.1.x, 2.2.x and 2.3.x kernel releases without any code-changes. | ||
| 793 | 3) Commandline-parameters are recognized again, even under Kernel 2.3.x or | ||
| 794 | higher. | ||
| 795 | - Michael Lang | ||
| 796 | |||
| 797 | April 27, 2000 (v3.2pre2) | ||
| 798 | 1) Bypassed commands get read by the adapter by one cycle instead of two. | ||
| 799 | This increases SCSI-performance. | ||
| 800 | 2) Synchronous datatransfer is provided for sure to be 5 MHz on older | ||
| 801 | SCSI and 10 MHz on internal F/W SCSI-adapter. | ||
| 802 | 3) New commandline parameters allow to force the adapter to slow down while | ||
| 803 | in synchronous transfer. Could be helpful for very old devices. | ||
| 804 | - Michael Lang | ||
| 805 | |||
| 806 | June 2, 2000 (v3.2pre5) | ||
| 807 | 1) Added Jim Shorney's contribution to make the activity indicator | ||
| 808 | flashing in addition to the LED-alphanumeric display-panel on | ||
| 809 | models 95A. To be enabled to choose this feature freely, a new | ||
| 810 | commandline parameter is added, called 'activity'. | ||
| 811 | 2) Added the READ_CONTROL bit for test_unit_ready SCSI-command. | ||
| 812 | 3) Added some suppress_exception bits to read_device_capacity and | ||
| 813 | all device_inquiry occurrences in the driver code. | ||
| 814 | 4) Complaints about the various KERNEL_VERSION implementations are | ||
| 815 | taken into account. Every local_LinuxKernelVersion occurrence is | ||
| 816 | now replaced by KERNEL_VERSION, defined in linux/version.h. | ||
| 817 | Corresponding changes were applied to ibmmca.h, too. This was a | ||
| 818 | contribution to all kernel-parts by Philipp Hahn. | ||
| 819 | - Michael Lang | ||
| 820 | |||
| 821 | July 17, 2000 (v3.2pre8) | ||
| 822 | A long period of collecting bugreports from all corners of the world | ||
| 823 | now lead to the following corrections to the code: | ||
| 824 | 1) SCSI-2 F/W support crashed with a COMMAND ERROR. The reason for this | ||
| 825 | was, that it is possible to disbale Fast-SCSI for the external bus. | ||
| 826 | The feature-control command, where this crash appeared regularly tried | ||
| 827 | to set the maximum speed of 10MHz synchronous transfer speed and that | ||
| 828 | reports a COMMAND ERROR, if external bus Fast-SCSI is disabled. Now, | ||
| 829 | the feature-command probes down from maximum speed until the adapter | ||
| 830 | stops to complain, which is at the same time the maximum possible | ||
| 831 | speed selected in the reference program. So, F/W external can run at | ||
| 832 | 5 MHz (slow-) or 10 MHz (fast-SCSI). During feature probing, the | ||
| 833 | COMMAND ERROR message is used to detect if the adapter does not complain. | ||
| 834 | 2) Up to now, only combined busmode is supported, if you use external | ||
| 835 | SCSI-devices, attached to the F/W-controller. If dual bus is selected, | ||
| 836 | only the internal SCSI-devices get accessed by Linux. For most | ||
| 837 | applications, this should do fine. | ||
| 838 | 3) Wide-SCSI-addressing (16-Bit) is now possible for the internal F/W | ||
| 839 | bus on the F/W adapter. If F/W adapter is detected, the driver | ||
| 840 | automatically uses the extended PUN/LUN <-> LDN mapping tables, which | ||
| 841 | are now new from 3.2pre8. This allows PUNs between 0 and 15 and should | ||
| 842 | provide more fun with the F/W adapter. | ||
| 843 | 4) Several machines use the SCSI: POS registers for internal/undocumented | ||
| 844 | storage of system relevant info. This confused the driver, mainly on | ||
| 845 | models 9595, as it expected no onboard SCSI only, if all POS in | ||
| 846 | the integrated SCSI-area are set to 0x00 or 0xff. Now, the mechanism | ||
| 847 | to check for integrated SCSI is much more restrictive and these problems | ||
| 848 | should be history. | ||
| 849 | - Michael Lang | ||
| 850 | |||
| 851 | July 18, 2000 (v3.2pre9) | ||
| 852 | This develop rather quickly at the moment. Two major things were still | ||
| 853 | missing in 3.2pre8: | ||
| 854 | 1) The adapter PUN for F/W adapters has 4-bits, while all other adapters | ||
| 855 | have 3-bits. This is now taken into account for F/W. | ||
| 856 | 2) When you select CONFIG_IBMMCA_SCSI_ORDER_STANDARD, you should | ||
| 857 | normally get the inverse probing order of your devices on the SCSI-bus. | ||
| 858 | The ANSI device order gets scrambled in version 3.2pre8!! Now, a new | ||
| 859 | and tested algorithm inverts the device-order on the SCSI-bus and | ||
| 860 | automatically avoids accidental access to whatever SCSI PUN the adapter | ||
| 861 | is set and works with SCSI- and Wide-SCSI-addressing. | ||
| 862 | - Michael Lang | ||
| 863 | |||
| 864 | July 23, 2000 (v3.2pre10 unpublished) | ||
| 865 | 1) LED panel display supports wide-addressing in ibmmca=display mode. | ||
| 866 | 2) Adapter-information and autoadaption to address-space is done. | ||
| 867 | 3) Auto-probing for maximum synchronous SCSI transfer rate is working. | ||
| 868 | 4) Optimization to some embedded function calls is applied. | ||
| 869 | 5) Added some comment for the user to wait for SCSI-devices being probed. | ||
| 870 | 6) Finished version 3.2 for Kernel 2.4.0. It least, I thought it is but... | ||
| 871 | - Michael Lang | ||
| 872 | |||
| 873 | July 26, 2000 (v3.2pre11) | ||
| 874 | 1) I passed a horrible weekend getting mad with NMIs on kernel 2.2.14 and | ||
| 875 | a model 9595. Asking around in the community, nobody except of me has | ||
| 876 | seen such errors. Weired, but I am trying to recompile everything on | ||
| 877 | the model 9595. Maybe, as I use a specially modified gcc, that could | ||
| 878 | cause problems. But, it was not the reason. The true background was, | ||
| 879 | that the kernel was compiled for i386 and the 9595 has a 486DX-2. | ||
| 880 | Normally, no troubles should appear, but for this special machine, | ||
| 881 | only the right processor support is working fine! | ||
| 882 | 2) Previous problems with synchronous speed, slowing down from one adapter | ||
| 883 | to the next during probing are corrected. Now, local variables store | ||
| 884 | the synchronous bitmask for every single adapter found on the MCA bus. | ||
| 885 | 3) LED alphanumeric panel support for XX95 systems is now showing some | ||
| 886 | alive rotator during boottime. This makes sense, when no monitor is | ||
| 887 | connected to the system. You can get rid of all display activity, if | ||
| 888 | you do not use any parameter or just ibmmcascsi=activity, for the | ||
| 889 | harddrive activity LED, existant on all PS/2, except models 8595-XXX. | ||
| 890 | If no monitor is available, please use ibmmcascsi=display, which works | ||
| 891 | fine together with the linuxinfo utility for the LED-panel. | ||
| 892 | - Michael Lang | ||
| 893 | |||
| 894 | July 29, 2000 (v3.2) | ||
| 895 | 1) Submission of this driver for kernel 2.4test-XX and 2.2.17. | ||
| 896 | - Michael Lang | ||
| 897 | |||
| 898 | December 28, 2000 (v3.2d / v4.0) | ||
| 899 | 1) The interrupt handler had some wrong statement to wait for. This | ||
| 900 | was done due to experimental reasons during 3.2 development but it | ||
| 901 | has shown that this is not stable enough. Going back to wait for the | ||
| 902 | adapter to be not busy is best. | ||
| 903 | 2) Inquiry requests can be shorter than 255 bytes of return buffer. Due | ||
| 904 | to a bug in the ibmmca_queuecommand routine, this buffer was forced | ||
| 905 | to 255 at minimum. If the memory address, this return buffer is pointing | ||
| 906 | to does not offer more space, invalid memory accesses destabilized the | ||
| 907 | kernel. | ||
| 908 | 3) version 4.0 is only valid for kernel 2.4.0 or later. This is necessary | ||
| 909 | to remove old kernel version dependent waste from the driver. 3.2d is | ||
| 910 | only distributed with older kernels but keeps compatibility with older | ||
| 911 | kernel versions. 4.0 and higher versions cannot be used with older | ||
| 912 | kernels anymore!! You must have at least kernel 2.4.0!! | ||
| 913 | 4) The commandline argument 'bypass' and all its functionality got removed | ||
| 914 | in version 4.0. This was never really necessary, as all troubles were | ||
| 915 | based on non-command related reasons up to now, so bypassing commands | ||
| 916 | did not help to avoid any bugs. It is kept in 3.2X for debugging reasons. | ||
| 917 | 5) Dynamical reassignment of ldns was again verified and analyzed to be | ||
| 918 | completely inoperational. This is corrected and should work now. | ||
| 919 | 6) All commands that get sent to the SCSI adapter were verified and | ||
| 920 | completed in such a way, that they are now completely conform to the | ||
| 921 | demands in the technical description of IBM. Main candidates were the | ||
| 922 | DEVICE_INQUIRY, REQUEST_SENSE and DEVICE_CAPACITY commands. They must | ||
| 923 | be tranferred by bypassing the internal command buffer of the adapter | ||
| 924 | or else the response can be a random result. GET_POS_INFO would be more | ||
| 925 | safe in usage, if one could use the SUPRESS_EXCEPTION_SHORT, but this | ||
| 926 | is not allowed by the technical references of IBM. (Sorry, folks, the | ||
| 927 | model 80 problem is still a task to be solved in a different way.) | ||
| 928 | 7) v3.2d is still hold back for some days for testing, while 4.0 is | ||
| 929 | released. | ||
| 930 | - Michael Lang | ||
| 931 | |||
| 932 | January 3, 2001 (v4.0a) | ||
| 933 | 1) A lot of complains after the 2.4.0-prerelease kernel came in about | ||
| 934 | the impossibility to compile the driver as a module. This problem is | ||
| 935 | solved. In combination with that problem, some unprecise declaration | ||
| 936 | of the function option_setup() gave some warnings during compilation. | ||
| 937 | This is solved, too by a forward declaration in ibmmca.c. | ||
| 938 | 2) #ifdef argument concerning CONFIG_SCSI_IBMMCA is no longer needed and | ||
| 939 | was entirely removed. | ||
| 940 | 3) Some switch statements got optimized in code, as some minor variables | ||
| 941 | in internal SCSI-command handlers. | ||
| 942 | - Michael Lang | ||
| 943 | |||
| 944 | 4 To do | ||
| 945 | ------- | ||
| 946 | - IBM SCSI-2 F/W external SCSI bus support in separate mode! | ||
| 947 | - It seems that the handling of bad disks is really bad - | ||
| 948 | non-existent, in fact. However, a low-level driver cannot help | ||
| 949 | much, if such things happen. | ||
| 950 | |||
| 951 | 5 Users' Manual | ||
| 952 | --------------- | ||
| 953 | 5.1 Commandline Parameters | ||
| 954 | -------------------------- | ||
| 955 | There exist several features for the IBM SCSI-subsystem driver. | ||
| 956 | The commandline parameter format is: | ||
| 957 | |||
| 958 | ibmmcascsi=<command1>,<command2>,<command3>,... | ||
| 959 | |||
| 960 | where commandN can be one of the following: | ||
| 961 | |||
| 962 | display Owners of a model 95 or other PS/2 systems with an | ||
| 963 | alphanumeric LED display may set this to have their | ||
| 964 | display showing the following output of the 8 digits: | ||
| 965 | |||
| 966 | ------DA | ||
| 967 | |||
| 968 | where '-' stays dark, 'D' shows the SCSI-device id | ||
| 969 | and 'A' shows the SCSI hostindex, being currently | ||
| 970 | accessed. During boottime, this will give the message | ||
| 971 | |||
| 972 | SCSIini* | ||
| 973 | |||
| 974 | on the LED-panel, where the * represents a rotator, | ||
| 975 | showing the activity during the probing phase of the | ||
| 976 | driver which can take up to two minutes per SCSI-adapter. | ||
| 977 | adisplay This works like display, but gives more optical overview | ||
| 978 | of the activities on the SCSI-bus. The display will have | ||
| 979 | the following output: | ||
| 980 | |||
| 981 | 6543210A | ||
| 982 | |||
| 983 | where the numbers 0 to 6 light up at the shown position, | ||
| 984 | when the SCSI-device is accessed. 'A' shows again the SCSI | ||
| 985 | hostindex. If display nor adisplay is set, the internal | ||
| 986 | PS/2 harddisk LED is used for media-activities. So, if | ||
| 987 | you really do not have a system with a LED-display, you | ||
| 988 | should not set display or adisplay. Keep in mind, that | ||
| 989 | display and adisplay can only be used alternatively. It | ||
| 990 | is not recommended to use this option, if you have some | ||
| 991 | wide-addressed devices e.g. at the SCSI-2 F/W adapter in | ||
| 992 | your system. In addition, the usage of the display for | ||
| 993 | other tasks in parallel, like the linuxinfo-utility makes | ||
| 994 | no sense with this option. | ||
| 995 | activity This enables the PS/2 harddisk LED activity indicator. | ||
| 996 | Most PS/2 have no alphanumeric LED display, but some | ||
| 997 | indicator. So you should use this parameter to activate it. | ||
| 998 | If you own model 9595 (Server95), you can have both, the | ||
| 999 | LED panel and the activity indicator in parallel. However, | ||
| 1000 | some PS/2s, like the 8595 do not have any harddisk LED | ||
| 1001 | activity indicator, which means, that you must use the | ||
| 1002 | alphanumeric LED display if you want to monitor SCSI- | ||
| 1003 | activity. | ||
| 1004 | bypass This is obsolete from driver version 4.0, as the adapters | ||
| 1005 | got that far understood, that the selection between | ||
| 1006 | integrated and bypassed commands should now work completely | ||
| 1007 | correct! For historical reasons, the old description is | ||
| 1008 | kept here: | ||
| 1009 | This commandline parameter forces the driver never to use | ||
| 1010 | SCSI-subsystems' integrated SCSI-command set. Except of | ||
| 1011 | the immediate assign, which is of vital importance for | ||
| 1012 | every IBM SCSI-subsystem to set its ldns right. Instead, | ||
| 1013 | the ordinary ANSI-SCSI-commands are used and passed by the | ||
| 1014 | controller to the SCSI-devices, therefore 'bypass'. The | ||
| 1015 | effort, done by the subsystem is quite bogus and at a | ||
| 1016 | minimum and therefore it should work everywhere. This | ||
| 1017 | could maybe solve troubles with old or integrated SCSI- | ||
| 1018 | controllers and nasty harddisks. Keep in mind, that using | ||
| 1019 | this flag will slow-down SCSI-accesses slightly, as the | ||
| 1020 | software generated commands are always slower than the | ||
| 1021 | hardware. Non-harddisk devices always get read/write- | ||
| 1022 | commands in bypass mode. On the most recent releases of | ||
| 1023 | the Linux IBM-SCSI-driver, the bypass command should be | ||
| 1024 | no longer a necessary thing, if you are sure about your | ||
| 1025 | SCSI-hardware! | ||
| 1026 | normal This is the parameter, introduced on the 2.0.x development | ||
| 1027 | rail by ZP Gu. This parameter defines the SCSI-device | ||
| 1028 | scan order in the new industry standard. This means, that | ||
| 1029 | the first SCSI-device is the one with the lowest pun. | ||
| 1030 | E.g. harddisk at pun=0 is scanned before harddisk at | ||
| 1031 | pun=6, which means, that harddisk at pun=0 gets sda | ||
| 1032 | and the one at pun=6 gets sdb. | ||
| 1033 | ansi The ANSI-standard for the right scan order, as done by | ||
| 1034 | IBM, Microware and Microsoft, scans SCSI-devices starting | ||
| 1035 | at the highest pun, which means, that e.g. harddisk at | ||
| 1036 | pun=6 gets sda and a harddisk at pun=0 gets sdb. If you | ||
| 1037 | like to have the same SCSI-device order, as in DOS, OS-9 | ||
| 1038 | or OS/2, just use this parameter. | ||
| 1039 | fast SCSI-I/O in synchronous mode is done at 5 MHz for IBM- | ||
| 1040 | SCSI-devices. SCSI-2 Fast/Wide Adapter/A external bus | ||
| 1041 | should then run at 10 MHz if Fast-SCSI is enabled, | ||
| 1042 | and at 5 MHz if Fast-SCSI is disabled on the external | ||
| 1043 | bus. This is the default setting when nothing is | ||
| 1044 | specified here. | ||
| 1045 | medium Synchronous rate is at 50% approximately, which means | ||
| 1046 | 2.5 MHz for IBM SCSI-adapters and 5.0 MHz for F/W ext. | ||
| 1047 | SCSI-bus (when Fast-SCSI speed enabled on external bus). | ||
| 1048 | slow The slowest possible synchronous transfer rate is set. | ||
| 1049 | This means 1.82 MHz for IBM SCSI-adapters and 2.0 MHz | ||
| 1050 | for F/W external bus at Fast-SCSI speed on the external | ||
| 1051 | bus. | ||
| 1052 | |||
| 1053 | A further option is that you can force the SCSI-driver to accept a SCSI- | ||
| 1054 | subsystem at a certain I/O-address with a predefined adapter PUN. This | ||
| 1055 | is done by entering | ||
| 1056 | |||
| 1057 | commandN = I/O-base | ||
| 1058 | commandN+1 = adapter PUN | ||
| 1059 | |||
| 1060 | e.g. ibmmcascsi=0x3540,7 will force the driver to detect a SCSI-subsystem | ||
| 1061 | at I/O-address 0x3540 with adapter PUN 7. Please only use this method, if | ||
| 1062 | the driver does really not recognize your SCSI-adapter! With driver version | ||
| 1063 | 3.2, this recognition of various adapters was hugely improved and you | ||
| 1064 | should try first to remove your commandline arguments of such type with a | ||
| 1065 | newer driver. I bet, it will be recognized correctly. Even multiple and | ||
| 1066 | different types of IBM SCSI-adapters should be recognized correctly, too. | ||
| 1067 | Use the forced detection method only as last solution! | ||
| 1068 | |||
| 1069 | Examples: | ||
| 1070 | |||
| 1071 | ibmmcascsi=adisplay | ||
| 1072 | |||
| 1073 | This will use the advanced display mode for the model 95 LED alphanumeric | ||
| 1074 | display. | ||
| 1075 | |||
| 1076 | ibmmcascsi=display,0x3558,7 | ||
| 1077 | |||
| 1078 | This will activate the default display mode for the model 95 LED display | ||
| 1079 | and will force the driver to accept a SCSI-subsystem at I/O-base 0x3558 | ||
| 1080 | with adapter PUN 7. | ||
| 1081 | |||
| 1082 | 5.2 Troubleshooting | ||
| 1083 | ------------------- | ||
| 1084 | The following FAQs should help you to solve some major problems with this | ||
| 1085 | driver. | ||
| 1086 | |||
| 1087 | Q: "Reset SCSI-devices at boottime" halts the system at boottime, why? | ||
| 1088 | A: This is only tested with the IBM SCSI Adapter w/cache. It is not | ||
| 1089 | yet prooved to run on other adapters, however you may be lucky. | ||
| 1090 | In version 3.1d this has been hugely improved and should work better, | ||
| 1091 | now. Normally you really won't need to activate this flag in the | ||
| 1092 | kernel configuration, as all post 1989 SCSI-devices should accept | ||
| 1093 | the reset-signal, when the computer is switched on. The SCSI- | ||
| 1094 | subsystem generates this reset while being initialized. This flag | ||
| 1095 | is really reserved for users with very old, very strange or self-made | ||
| 1096 | SCSI-devices. | ||
| 1097 | Q: Why is the SCSI-order of my drives mirrored to the device-order | ||
| 1098 | seen from OS/2 or DOS ? | ||
| 1099 | A: It depends on the operating system, if it looks at the devices in | ||
| 1100 | ANSI-SCSI-standard (starting from pun 6 and going down to pun 0) or | ||
| 1101 | if it just starts at pun 0 and counts up. If you want to be conform | ||
| 1102 | with OS/2 and DOS, you have to activate this flag in the kernel | ||
| 1103 | configuration or you should set 'ansi' as parameter for the kernel. | ||
| 1104 | The parameter 'normal' sets the new industry standard, starting | ||
| 1105 | from pun 0, scanning up to pun 6. This allows you to change your | ||
| 1106 | opinion still after having already compiled the kernel. | ||
| 1107 | Q: Why I cannot find the IBM MCA SCSI support in the config menue? | ||
| 1108 | A: You have to activate MCA bus support, first. | ||
| 1109 | Q: Where can I find the latest info about this driver? | ||
| 1110 | A: See the file MAINTAINERS for the current WWW-address, which offers | ||
| 1111 | updates, info and Q/A lists. At this files' origin, the webaddress | ||
| 1112 | was: http://www.uni-mainz.de/~langm000/linux.html | ||
| 1113 | Q: My SCSI-adapter is not recognized by the driver, what can I do? | ||
| 1114 | A: Just force it to be recognized by kernel parameters. See section 5.1. | ||
| 1115 | If this really happens, do also send e-mail to the maintainer, as | ||
| 1116 | forced detection should be never necessary. Forced detection is in | ||
| 1117 | principal some flaw of the driver adapter detection and goes into | ||
| 1118 | bugreports. | ||
| 1119 | Q: The driver screws up, if it starts to probe SCSI-devices, is there | ||
| 1120 | some way out of it? | ||
| 1121 | A: Yes, that was some recognition problem of the correct SCSI-adapter | ||
| 1122 | and its I/O base addresses. Upgrade your driver to the latest release | ||
| 1123 | and it should be fine again. | ||
| 1124 | Q: I get a message: panic IBM MCA SCSI: command error .... , what can | ||
| 1125 | I do against this? | ||
| 1126 | A: Previously, I followed the way by ignoring command errors by using | ||
| 1127 | ibmmcascsi=forgiveall, but this command no longer exists and is | ||
| 1128 | obsolete. If such a problem appears, it is caused by some segmentation | ||
| 1129 | fault of the driver, which maps to some unallowed area. The latest | ||
| 1130 | version of the driver should be ok, as most bugs have been solved. | ||
| 1131 | Q: There are still kernel panics, even after having set | ||
| 1132 | ibmmcascsi=forgiveall. Are there other possibilities to prevent | ||
| 1133 | such panics? | ||
| 1134 | A: No, get just the latest release of the driver and it should work | ||
| 1135 | better and better with increasing version number. Forget about this | ||
| 1136 | ibmmcascsi=forgiveall, as also ignorecmd are obsolete.! | ||
| 1137 | Q: Linux panics or stops without any comment, but it is probable, that my | ||
| 1138 | harddisk(s) have bad blocks. | ||
| 1139 | A: Sorry, the bad-block handling is still a feeble point of this driver, | ||
| 1140 | but is on the schedule for development in the near future. | ||
| 1141 | Q: Linux panics while dynamically assigning SCSI-ids or ldns. | ||
| 1142 | A: If you disconnect a SCSI-device from the machine, while Linux is up | ||
| 1143 | and the driver uses dynamical reassignment of logical device numbers | ||
| 1144 | (ldn), it really gets "angry" if it won't find devices, that were still | ||
| 1145 | present at boottime and stops Linux. | ||
| 1146 | Q: The system does not recover after an abort-command has been generated. | ||
| 1147 | A: This is regrettably true, as it is not yet understood, why the | ||
| 1148 | SCSI-adapter does really NOT generate any interrupt at the end of | ||
| 1149 | the abort-command. As no interrupt is generated, the abort command | ||
| 1150 | cannot get finished and the system hangs, sorry, but checks are | ||
| 1151 | running to hunt down this problem. If there is a real pending command, | ||
| 1152 | the interrupt MUST get generated after abort. In this case, it | ||
| 1153 | should finish well. | ||
| 1154 | Q: The system gets in bad shape after a SCSI-reset, is this known? | ||
| 1155 | A: Yes, as there are a lot of prescriptions (see the Linux Hackers' | ||
| 1156 | Guide) what has to be done for reset, we still share the bad shape of | ||
| 1157 | the reset functions with all other low level SCSI-drivers. | ||
| 1158 | Astonishingly, reset works in most cases quite ok, but the harddisks | ||
| 1159 | won't run in synchonous mode anymore after a reset, until you reboot. | ||
| 1160 | Q: Why does my XXX w/Cache adapter not use read-prefetch? | ||
| 1161 | A: Ok, that is not completely possible. If a cache is present, the | ||
| 1162 | adapter tries to use it internally. Explicitly, one can use the cache | ||
| 1163 | with a read prefetch command, maybe in future, but this requires | ||
| 1164 | some major overhead of SCSI-commands that risks the performance to | ||
| 1165 | go down more than it gets improved. Tests with that are running. | ||
| 1166 | Q: I have a IBM SCSI-2 Fast/Wide adapter, it boots in some way and hangs. | ||
| 1167 | A: Yes, that is understood, as for sure, your SCSI-2 Fast/Wide adapter | ||
| 1168 | was in such a case recognized as integrated SCSI-adapter or something | ||
| 1169 | else, but not as the correct adapter. As the I/O-ports get assigned | ||
| 1170 | wrongly by that reason, the system should crash in most cases. You | ||
| 1171 | should upgrade to the latest release of the SCSI-driver. The | ||
| 1172 | recommended version is 3.2 or later. Here, the F/W support is in | ||
| 1173 | a stable and reliable condition. Wide-addressing is in addition | ||
| 1174 | supported. | ||
| 1175 | Q: I get a Ooops message and something like "killing interrupt". | ||
| 1176 | A: The reason for this is that the IBM SCSI-subsystem only sends a | ||
| 1177 | termination status back, if some error appeared. In former releases | ||
| 1178 | of the driver, it was not checked, if the termination status block | ||
| 1179 | is NULL. From version 3.2, it is taken care of this. | ||
| 1180 | Q: I have a F/W adapter and the driver sees my internal SCSI-devices, | ||
| 1181 | but ignores the external ones. | ||
| 1182 | A: Select combined busmode in the IBM config-program and check for that | ||
| 1183 | no SCSI-id on the external devices appears on internal devices. | ||
| 1184 | Reboot afterwards. Dual busmode is supported, but works only for the | ||
| 1185 | internal bus, yet. External bus is still ignored. Take care for your | ||
| 1186 | SCSI-ids. If combined bus-mode is activated, on some adapters, | ||
| 1187 | the wide-addressing is not possible, so devices with ids between 8 | ||
| 1188 | and 15 get ignored by the driver & adapter! | ||
| 1189 | Q: I have a 9595 and I get a NMI during heavy SCSI I/O e.g. during fsck. | ||
| 1190 | A COMMAND ERROR is reported and characters on the screen are missing. | ||
| 1191 | Warm reboot is not possible. Things look like quite weired. | ||
| 1192 | A: Check the processor type of your 9595. If you have an 80486 or 486DX-2 | ||
| 1193 | processor complex on your mainboard and you compiled a kernel that | ||
| 1194 | supports 80386 processors, it is possible, that the kernel cannot | ||
| 1195 | keep track of the PS/2 interrupt handling and stops on an NMI. Just | ||
| 1196 | compile a kernel for the correct processor type of your PS/2 and | ||
| 1197 | everything should be fine. This is necessary even if one assumes, | ||
| 1198 | that some 80486 system should be downward compatible to 80386 | ||
| 1199 | software. | ||
| 1200 | Q: Some commands hang and interrupts block the machine. After some | ||
| 1201 | timeout, the syslog reports that it tries to call abort, but the | ||
| 1202 | machine is frozen. | ||
| 1203 | A: This can be a busy wait bug in the interrupt handler of driver | ||
| 1204 | version 3.2. You should at least upgrade to 3.2c if you use | ||
| 1205 | kernel < 2.4.0 and driver version 4.0 if you use kernel 2.4.0 or | ||
| 1206 | later (including all test releases). | ||
| 1207 | Q: I have a PS/2 model 80 and more than 16 MBytes of RAM. The driver | ||
| 1208 | completely refuses to work, reports NMIs, COMMAND ERRORs or other | ||
| 1209 | ambiguous stuff. When reducing the RAM size down below 16 MB, | ||
| 1210 | everything is running smoothly. | ||
| 1211 | A: No real answer, yet. In any case, one should force the kernel to | ||
| 1212 | present SCBs only below the 16 MBytes barrier. Maybe this solves the | ||
| 1213 | problem. Not yet tried, but guessing that it could work. To get this, | ||
| 1214 | set unchecked_isa_dma argument of ibmmca.h from 0 to 1. | ||
| 1215 | |||
| 1216 | 5.3 Bugreports | ||
| 1217 | -------------- | ||
| 1218 | If you really find bugs in the sourcecode or the driver will successfully | ||
| 1219 | refuse to work on your machine, you should send a bug report to me. The | ||
| 1220 | best for this is to follow the instructions on the WWW-page for this | ||
| 1221 | driver. Fill out the bug-report form, placed on the WWW-page and ship it, | ||
| 1222 | so the bugs can be taken into account with maximum efforts. But, please | ||
| 1223 | do not send bug reports about this driver to Linus Torvalds or Leonard | ||
| 1224 | Zubkoff, as Linus is burried in E-Mail and Leonard is supervising all | ||
| 1225 | SCSI-drivers and won't have the time left to look inside every single | ||
| 1226 | driver to fix a bug and especially DO NOT send modified code to Linus | ||
| 1227 | Torvalds or Alan J. Cox which has not been checked here!!! They are both | ||
| 1228 | quite burried in E-mail (as me, sometimes, too) and one should first check | ||
| 1229 | for problems on my local teststand. Recently, I got a lot of | ||
| 1230 | bugreports for errors in the ibmmca.c code, which I could not imagine, but | ||
| 1231 | a look inside some Linux-distribution showed me quite often some modified | ||
| 1232 | code, which did no longer work on most other machines than the one of the | ||
| 1233 | modifier. Ok, so now that there is maintenance service available for this | ||
| 1234 | driver, please use this address first in order to keep the level of | ||
| 1235 | confusion low. Thank you! | ||
| 1236 | |||
| 1237 | When you get a SCSI-error message that panics your system, a list of | ||
| 1238 | register-entries of the SCSI-subsystem is shown (from Version 3.1d). With | ||
| 1239 | this list, it is very easy for the maintainer to localize the problem in | ||
| 1240 | the driver or in the configuration of the user. Please write down all the | ||
| 1241 | values from this report and send them to the maintainer. This would really | ||
| 1242 | help a lot and makes life easier concerning misunderstandings. | ||
| 1243 | |||
| 1244 | Use the bug-report form (see 5.4 for its address) to send all the bug- | ||
| 1245 | stuff to the maintainer or write e-mail with the values from the table. | ||
| 1246 | |||
| 1247 | 5.4 Support WWW-page | ||
| 1248 | -------------------- | ||
| 1249 | The address of the IBM SCSI-subsystem supporting WWW-page is: | ||
| 1250 | |||
| 1251 | http://www.uni-mainz.de/~langm000/linux.html | ||
| 1252 | |||
| 1253 | Here you can find info about the background of this driver, patches, | ||
| 1254 | troubleshooting support, news and a bugreport form. Please check that | ||
| 1255 | WWW-page regularly for latest hints. If ever this URL changes, please | ||
| 1256 | refer to the MAINTAINERS file in order to get the latest address. | ||
| 1257 | |||
| 1258 | For the bugreport, please fill out the formular on the corresponding | ||
| 1259 | WWW-page. Read the dedicated instructions and write as much as you | ||
| 1260 | know about your problem. If you do not like such formulars, please send | ||
| 1261 | some e-mail directly, but at least with the same information as required by | ||
| 1262 | the formular. | ||
| 1263 | |||
| 1264 | If you have extensive bugreports, including Ooops messages and | ||
| 1265 | screen-shots, please feel free to send it directly to the address | ||
| 1266 | of the maintainer, too. The current address of the maintainer is: | ||
| 1267 | |||
| 1268 | Michael Lang <langa2@kph.uni-mainz.de> | ||
| 1269 | |||
| 1270 | 6 References | ||
| 1271 | ------------ | ||
| 1272 | IBM Corp., "Update for the PS/2 Hardware Interface Technical Reference, | ||
| 1273 | Common Interfaces", Armonk, September 1991, PN 04G3281, | ||
| 1274 | (available in the U.S. for $21.75 at 1-800-IBM-PCTB or in Germany for | ||
| 1275 | around 40,-DM at "Hallo IBM"). | ||
| 1276 | |||
| 1277 | IBM Corp., "Personal System/2 Micro Channel SCSI | ||
| 1278 | Adapter with Cache Technical Reference", Armonk, March 1990, PN 68X2365. | ||
| 1279 | |||
| 1280 | IBM Corp., "Personal System/2 Micro Channel SCSI | ||
| 1281 | Adapter Technical Reference", Armonk, March 1990, PN 68X2397. | ||
| 1282 | |||
| 1283 | IBM Corp., "SCSI-2 Fast/Wide Adapter/A Technical Reference - Dual Bus", | ||
| 1284 | Armonk, March 1994, PN 83G7545. | ||
| 1285 | |||
| 1286 | Friedhelm Schmidt, "SCSI-Bus und IDE-Schnittstelle - Moderne Peripherie- | ||
| 1287 | Schnittstellen: Hardware, Protokollbeschreibung und Anwendung", 2. Aufl. | ||
| 1288 | Addison Wesley, 1996. | ||
| 1289 | |||
| 1290 | Michael K. Johnson, "The Linux Kernel Hackers' Guide", Version 0.6, Chapel | ||
| 1291 | Hill - North Carolina, 1995 | ||
| 1292 | |||
| 1293 | Andreas Kaiser, "SCSI TAPE BACKUP for OS/2 2.0", Version 2.12, Stuttgart | ||
| 1294 | 1993 | ||
| 1295 | |||
| 1296 | Helmut Rompel, "IBM Computerwelt GUIDE", What is what bei IBM., Systeme * | ||
| 1297 | Programme * Begriffe, IWT-Verlag GmbH - Muenchen, 1988 | ||
| 1298 | |||
| 1299 | 7 Credits to | ||
| 1300 | ------------ | ||
| 1301 | 7.1 People | ||
| 1302 | ---------- | ||
| 1303 | Klaus Grimm | ||
| 1304 | who already a long time ago gave me the old code from the | ||
| 1305 | SCSI-driver in order to get it running for some old machine | ||
| 1306 | in our institute. | ||
| 1307 | Martin Kolinek | ||
| 1308 | who wrote the first release of the IBM SCSI-subsystem driver. | ||
| 1309 | Chris Beauregard | ||
| 1310 | who for a long time maintained MCA-Linux and the SCSI-driver | ||
| 1311 | in the beginning. Chris, wherever you are: Cheers to you! | ||
| 1312 | Klaus Kudielka | ||
| 1313 | with whom in the 2.1.x times, I had a quite fruitful | ||
| 1314 | cooperation to get the driver running as a module and to get | ||
| 1315 | it running with multiple SCSI-adapters. | ||
| 1316 | David Weinehall | ||
| 1317 | for his excellent maintenance of the MCA-stuff and the quite | ||
| 1318 | detailed bug reports and ideas for this driver (and his | ||
| 1319 | patience ;-)). | ||
| 1320 | Alan J. Cox | ||
| 1321 | for his bugreports and his bold activities in cross-checking | ||
| 1322 | the driver-code with his teststand. | ||
| 1323 | |||
| 1324 | 7.2 Sponsors & Supporters | ||
| 1325 | ------------------------- | ||
| 1326 | "Hallo IBM", | ||
| 1327 | IBM-Deutschland GmbH | ||
| 1328 | the service of IBM-Deutschland for customers. Their E-Mail | ||
| 1329 | service is unbeatable. Whatever old stuff I asked for, I | ||
| 1330 | always got some helpful answers. | ||
| 1331 | Karl-Otto Reimers, | ||
| 1332 | IBM Klub - Sparte IBM Geschichte, Sindelfingen | ||
| 1333 | for sending me a copy of the w/Cache manual from the | ||
| 1334 | IBM-Deutschland archives. | ||
| 1335 | Harald Staiger | ||
| 1336 | for his extensive hardware donations which allows me today | ||
| 1337 | still to test the driver in various constellations. | ||
| 1338 | Erich Fritscher | ||
| 1339 | for his very kind sponsoring. | ||
| 1340 | Louis Ohland, | ||
| 1341 | Charles Lasitter | ||
| 1342 | for support by shipping me an IBM SCSI-2 Fast/Wide manual. | ||
| 1343 | In addition, the contribution of various hardware is quite | ||
| 1344 | decessive and will make it possible to add FWSR (RAID) | ||
| 1345 | adapter support to the driver in the near future! So, | ||
| 1346 | complaints about no RAID support won't remain forever. | ||
| 1347 | Yes, folks, that is no joke, RAID support is going to rise! | ||
| 1348 | Erik Weber | ||
| 1349 | for the great deal we made about a model 9595 and the nice | ||
| 1350 | surrounding equipment and the cool trip to Mannheim | ||
| 1351 | second-hand computer market. In addition, I would like | ||
| 1352 | to thank him for his exhaustive SCSI-driver testing on his | ||
| 1353 | 95er PS/2 park. | ||
| 1354 | Anthony Hogbin | ||
| 1355 | for his direct shipment of a SCSI F/W adapter, which allowed | ||
| 1356 | me immediately on the first stage to try it on model 8557 | ||
| 1357 | together with onboard SCSI adapter and some SCSI w/Cache. | ||
| 1358 | Andreas Hotz | ||
| 1359 | for his support by memory and an IBM SCSI-adapter. Collecting | ||
| 1360 | all this together now allows me to try really things with | ||
| 1361 | the driver at maximum load and variety on various models in | ||
| 1362 | a very quick and efficient way. | ||
| 1363 | Peter Jennewein | ||
| 1364 | for his model 30, which serves me as part of my teststand | ||
| 1365 | and his cool remark about how you make an ordinary diskette | ||
| 1366 | drive working and how to connect it to an IBM-diskette port. | ||
| 1367 | Johannes Gutenberg-Universitaet, Mainz & | ||
| 1368 | Institut fuer Kernphysik, Mainz Microtron (MAMI) | ||
| 1369 | for the offered space, the link, placed on the central | ||
| 1370 | homepage and the space to store and offer the driver and | ||
| 1371 | related material and the free working times, which allow | ||
| 1372 | me to answer all your e-mail. | ||
| 1373 | |||
| 1374 | 8 Trademarks | ||
| 1375 | ------------ | ||
| 1376 | IBM, PS/2, OS/2, Microchannel are registered trademarks of International | ||
| 1377 | Business Machines Corporation | ||
| 1378 | |||
| 1379 | MS-DOS is a registered trademark of Microsoft Corporation | ||
| 1380 | |||
| 1381 | Microware, OS-9 are registered trademarks of Microware Systems | ||
| 1382 | |||
| 1383 | 9 Disclaimer | ||
| 1384 | ------------ | ||
| 1385 | Beside the GNU General Public License and the dependent disclaimers and disclaimers | ||
| 1386 | concerning the Linux-kernel in special, this SCSI-driver comes without any | ||
| 1387 | warranty. Its functionality is tested as good as possible on certain | ||
| 1388 | machines and combinations of computer hardware, which does not exclude, | ||
| 1389 | that dataloss or severe damage of hardware is possible while using this | ||
| 1390 | part of software on some arbitrary computer hardware or in combination | ||
| 1391 | with other software packages. It is highly recommended to make backup | ||
| 1392 | copies of your data before using this software. Furthermore, personal | ||
| 1393 | injuries by hardware defects, that could be caused by this SCSI-driver are | ||
| 1394 | not excluded and it is highly recommended to handle this driver with a | ||
| 1395 | maximum of carefulness. | ||
| 1396 | |||
| 1397 | This driver supports hardware, produced by International Business Machines | ||
| 1398 | Corporation (IBM). | ||
| 1399 | |||
| 1400 | ------ | ||
| 1401 | Michael Lang | ||
| 1402 | (langa2@kph.uni-mainz.de) | ||