1.\" $NetBSD: ahc.4,v 1.20 2002/02/13 08:17:30 ross Exp $ 2.\" 3.\" Copyright (c) 1995, 1996, 1997, 1998, 2000 4.\" Justin T. Gibbs. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. The name of the author may not be used to endorse or promote products 15.\" derived from this software without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" 28.\" $FreeBSD: src/share/man/man4/ahc.4,v 1.22 2000/02/14 16:40:58 gibbs Exp $ 29.\" 30.Dd February 13, 2000 31.Dt AHC 4 32.Os 33.\".Os FreeBSD 34.Sh NAME 35.Nm ahc 36.Nd Adaptec VL/EISA/PCI/CardBus SCSI host adapter driver 37.Sh SYNOPSIS 38.ie 0 \{ 39For one or more VL/EISA cards: 40.Cd device eisa 41.Cd device ahc 42\} 43\{For VL cards: 44.Cd ahc0 at isa? port ? irq ? 45.Pp 46For EISA cards: 47.Cd ahc* at eisa? slot ?\} 48.Pp 49.ie 0 \{ 50For one or more PCI cards: 51.Cd device pci 52.Cd device ahc 53\} 54\{For PCI cards: 55.Cd ahc* at pci? dev ? function ? 56.Pp 57For CardBus cards: 58.Cd ahc* at cardbus? dev ? function ?\} 59.Pp 60To allow PCI adapters to use memory mapped I/O if enabled: 61.Cd options AHC_ALLOW_MEMIO 62.Pp 63.if 0 \{ 64To configure one or more controllers to assume the target role: 65.Cd options AHC_TMODE_ENABLE \*[Lt]bitmask of units\*[Gt] 66.Pp 67\} 68.ie 0 \{ 69For one or more SCSI busses: 70.Cd device scbus0 at ahc0 71\} 72\{For 73.Tn SCSI 74busses: 75.Cd scsibus* at ahc?\} 76.Sh DESCRIPTION 77.ie 0 \{ 78This driver provides access to the 79.Tn SCSI 80bus(es) connected to Adaptec 81.Tn AIC7770 , 82.Tn AIC7850 , 83.Tn AIC7860 , 84.Tn AIC7870 , 85.Tn AIC7880 , 86.Tn AIC7890 , 87.Tn AIC7891 , 88.Tn AIC7892 , 89.Tn AIC7895 , 90.Tn AIC7896 , 91.Tn AIC7897 92and 93.Tn AIC7899 94host adapter chips. 95These chips are found on many motherboards as well as the following 96Adaptec SCSI controller cards: 97.Tn 274X(W) , 98.Tn 274X(T) , 99.Tn 284X , 100.Tn 2910 , 101.Tn 2915 , 102.Tn 2920C , 103.Tn 2930C , 104.Tn 2930U2 , 105.Tn 2940 , 106.Tn 2940U , 107.Tn 2940AU , 108.Tn 2940UW , 109.Tn 2940UW Dual , 110.Tn 2940UW Pro , 111.Tn 2940U2W , 112.Tn 2940U2B , 113.Tn 2950U2W , 114.Tn 2950U2B , 115.Tn 19160B , 116.Tn 29160B , 117.Tn 29160N , 118.Tn 3940 , 119.Tn 3940U , 120.Tn 3940AU , 121.Tn 3940UW , 122.Tn 3940AUW , 123.Tn 3940U2W , 124.Tn 3950U2 , 125.Tn 3960 , 126.Tn 39160 , 127.Tn 3985 , 128and 129.Tn 4944UW . 130\} 131\{The 132.Nm 133device driver supports 134.Tn SCSI 135controllers based on 136.Tn Adaptec 137.Tn AIC77xx 138and 139.Tn AIC78xx 140.Tn SCSI 141host adapter chips found on many motherboards as well as 142.Tn Adaptec 143.Tn SCSI 144controller cards.\} 145.Pp 146Driver features include support for twin and wide busses, 147fast, ultra or ultra2 synchronous transfers depending on controller type, 148.ie 0 \{ 149tagged queuing, SCB paging, and target mode. 150\} 151\{ 152tagged queuing and SCB paging.\} 153.Pp 154Memory mapped I/O can be enabled for PCI devices with the 155.Dq Dv AHC_ALLOW_MEMIO 156configuration option. 157Memory mapped I/O is more efficient than the alternative, programmed I/O. 158Most PCI BIOSes will map devices so that either technique for communicating 159with the card is available. 160In some cases, 161usually when the PCI device is sitting behind a PCI-\*[Gt]PCI bridge, 162the BIOS may fail to properly initialize the chip for memory mapped I/O. 163The typical symptom of this problem is a system hang if memory mapped I/O 164is attempted. 165Most modern motherboards perform the initialization correctly and work fine 166with this option enabled. 167.Pp 168.if 0 \{ 169Individual controllers may be configured to operate in the target role 170through the 171.Dq Dv AHC_TMODE_ENABLE 172configuration option. The value assigned to this option should be a bitmap 173of all units where target mode is desired. 174For example, a value of 0x25, would enable target mode on units 0, 2, and 5. 175.Pp 176\} 177Per target configuration performed in the 178.Tn SCSI-Select 179menu, accessible at boot 180in 181.No non- Ns Tn EISA 182models, 183or through an 184.Tn EISA 185configuration utility for 186.Tn EISA 187models, 188is honored by this driver. 189This includes synchronous/asynchronous transfers, 190maximum synchronous negotiation rate, 191wide transfers, 192disconnection, 193the host adapter's SCSI ID, 194and, 195in the case of 196.Tn EISA 197Twin Channel controllers, 198the primary channel selection. 199For systems that store non-volatile settings in a system specific manner 200rather than a serial eeprom directly connected to the aic7xxx controller, 201the 202.Tn BIOS 203must be enabled for the driver to access this information. 204This restriction applies to all 205.Tn EISA 206and many motherboard configurations. 207.Pp 208Note that I/O addresses are determined automatically by the probe routines, 209but care should be taken when using a 284x 210.Pq Tn VESA No local bus controller 211in an 212.Tn EISA 213system. The jumpers setting the I/O area for the 284x should match the 214.Tn EISA 215slot into which the card is inserted to prevent conflicts with other 216.Tn EISA 217cards. 218.Pp 219Performance and feature sets vary throughout the aic7xxx product line. 220The following table provides a comparison of the different chips supported 221by the 222.Nm 223driver. Note that wide and twin channel features, although always supported 224by a particular chip, may be disabled in a particular motherboard or card 225design. 226.Pp 227.Bd -filled -offset indent 228.Bl -column "aic7770 " "10 " "EISA/VL " "10MHz " "16bit " "SCBs " Features 229.Em "Chip MIPS Bus MaxSync MaxWidth SCBs Features" 230aic7770 10 EISA/VL 10MHz 16Bit 4 1 231aic7850 10 PCI/32 10MHz 8Bit 3 232aic7860 10 PCI/32 20MHz 8Bit 3 233aic7870 10 PCI/32 10MHz 16Bit 16 234aic7880 10 PCI/32 20MHz 16Bit 16 235aic7890 20 PCI/32 40MHz 16Bit 16 3 4 5 6 7 8 236aic7891 20 PCI/64 40MHz 16Bit 16 3 4 5 6 7 8 237aic7892 20 PCI/64 80MHz 16Bit 16 3 4 5 6 7 8 238aic7895 15 PCI/32 20MHz 16Bit 16 2 3 4 5 239aic7895C 15 PCI/32 20MHz 16Bit 16 2 3 4 5 8 240aic7896 20 PCI/32 40MHz 16Bit 16 2 3 4 5 6 7 8 241aic7897 20 PCI/64 40MHz 16Bit 16 2 3 4 5 6 7 8 242aic7899 20 PCI/64 80MHz 16Bit 16 2 3 4 5 6 7 8 243.El 244.Bl -enum -compact 245.It 246Multiplexed Twin Channel Device - One controller servicing two busses. 247.It 248Multi-function Twin Channel Device - Two controllers on one chip. 249.It 250Command Channel Secondary DMA Engine - Allows scatter gather list and 251SCB prefetch. 252.It 25364 Byte SCB Support - SCSI CDB is embedded in the SCB to eliminate an extra DMA. 254.It 255Block Move Instruction Support - Doubles the speed of certain sequencer 256operations. 257.It 258.Sq Bayonet 259style Scatter Gather Engine - Improves S/G prefetch performance. 260.It 261Queuing Registers - Allows queuing of new transactions without pausing the 262sequencer. 263.It 264Multiple Target IDs - Allows the controller to respond to selection as a 265target on multiple SCSI IDs. 266.El 267.Ed 268.Sh HARDWARE 269Supported 270.Tn SCSI 271controllers include: 272.Pp 273.Bl -item -offset indent 274.It 275.Tn Adaptec AHA-2742W 276EISA Fast Wide SCSI adapter 277.It 278.Tn Adaptec AHA-274xAT 279EISA dual channel Fast SCSI adapter 280.It 281.Tn Adaptec AHA-284x 282VL Fast SCSI adapter 283.It 284.Tn Adaptec AHA-2910 285PCI Fast SCSI adapter (no SCSI BIOS) 286.It 287.Tn Adaptec AHA-2915 288PCI Fast SCSI adapter (no SCSI BIOS) 289.It 290.Tn Adaptec AHA-2920C 291PCI Fast SCSI adapter 292.Bl -item -offset indent 293.It 294Note: 295Adaptec AHA-2920/A which use the Future Domain's chips are not supported 296by this driver. 297.El 298.It 299.Tn Adaptec AHA-2930C 300PCI Ultra SCSI adapter 301.It 302.Tn Adaptec AHA-2930U2 303PCI Ultra2 Wide LVD SCSI adapter 304.It 305.Tn Adaptec AHA-2940 306PCI Fast SCSI adapter 307.It 308.Tn Adaptec AHA-2940U 309PCI Ultra SCSI adapter 310.It 311.Tn Adaptec AHA-2940AU 312PCI Ultra SCSI adapter 313.It 314.Tn Adaptec AHA-2940UW 315PCI Ultra Wide SCSI adapter 316.It 317.Tn Adaptec AHA-2940UW Dual 318PCI dual channel Ultra Wide SCSI adapter 319.It 320.Tn Adaptec AHA-2940UW Pro 321PCI Ultra Wide SCSI adapter 322.It 323.Tn Adaptec AHA-2940U2W 324PCI Ultra2 Wide LVD SCSI adapter 325.It 326.Tn Adaptec AHA-2940U2B 327PCI Ultra2 Wide LVD SCSI adapter 328.It 329.Tn Adaptec AHA-2944W 330PCI Fast Wide Differential SCSI adapter 331.It 332.Tn Adaptec AHA-2944UW 333PCI Ultra Wide Differential SCSI adapter 334.It 335.Tn Adaptec AHA-2950U2W 336.It 337.Tn Adaptec AHA-2950U2B 33864bit PCI Ultra2 Wide LVD SCSI adapter 339.It 340.Tn Adaptec AHA-19160B 341PCI Ultra160 Wide LVD SCSI adapter 342.It 343.Tn Adaptec AHA-29160N 344PCI Ultra160 Wide LVD SCSI adapter 345.It 346.Tn Adaptec AHA-29160B 34764bit PCI Ultra160 Wide LVD SCSI adapter 348.It 349.Tn Adaptec AHA-3940 350PCI dual channel Fast SCSI adapter 351.It 352.Tn Adaptec AHA-3940U 353PCI dual channel Ultra SCSI adapter 354.It 355.Tn Adaptec AHA-3940AU 356PCI dual channel Ultra SCSI adapter 357.It 358.Tn Adaptec AHA-3940UW 359PCI dual channel Ultra Wide SCSI adapter 360.It 361.Tn Adaptec AHA-3940AUW 362PCI dual channel Ultra Wide SCSI adapter 363.It 364.Tn Adaptec AHA-3940U2W 365PCI dual channel Ultra2 Wide LVD SCSI adapter 366.It 367.Tn Adaptec AHA-3950U2 36864bit PCI dual channel Ultra2 Wide LVD SCSI adapter 369.It 370.Tn Adaptec AHA-3960 37164bit PCI dual channel Ultra160 Wide LVD SCSI adapter 372.It 373.Tn Adaptec AHA-3985 374PCI dual channel Fast SCSI RAID adapter 375.It 376.Tn Adaptec AHA-39160 37764bit PCI dual channel Ultra160 Wide LVD SCSI adapter 378.It 379.Tn Adaptec AHA-4944UW 380PCI quad channel PCI Ultra Wide Differential SCSI adapter 381.It 382Other SCSI controllers based on the 383.Tn Adaptec 384.Tn AIC7770 , 385.Tn AIC7850 , 386.Tn AIC7860 , 387.Tn AIC7870 , 388.Tn AIC7880 , 389.Tn AIC7890 , 390.Tn AIC7891 , 391.Tn AIC7892 , 392.Tn AIC7895 , 393.Tn AIC7896 , 394.Tn AIC7897 395and 396.Tn AIC7899 397.Tn SCSI 398host adapter chips. 399.El 400.Sh SCSI CONTROL BLOCKS (SCBs) 401Every transaction sent to a device on the SCSI bus is assigned a 402.Sq SCSI Control Block 403(SCB). The SCB contains all of the information required by the 404controller to process a transaction. The chip feature table lists 405the number of SCBs that can be stored in on-chip memory. All chips 406with model numbers greater than or equal to 7870 allow for the on chip 407SCB space to be augmented with external SRAM up to a maximum of 255 SCBs. 408Very few Adaptec controller configurations have external SRAM. 409.Pp 410If external SRAM is not available, SCBs are a limited resource. 411Using the SCBs in a straight forward manner would only allow the driver to 412handle as many concurrent transactions as there are physical SCBs. 413To fully utilize the SCSI bus and the devices on it, 414requires much more concurrency. 415The solution to this problem is 416.Em SCB Paging , 417a concept similar to memory paging. SCB paging takes advantage of 418the fact that devices usually disconnect from the SCSI bus for long 419periods of time without talking to the controller. The SCBs 420for disconnected transactions are only of use to the controller 421when the transfer is resumed. When the host queues another transaction 422for the controller to execute, the controller firmware will use a 423free SCB if one is available. Otherwise, the state of the most recently 424disconnected (and therefor most likely to stay disconnected) SCB is 425saved, via dma, to host memory, and the local SCB reused to start 426the new transaction. This allows the controller to queue up to 427255 transactions regardless of the amount of SCB space. Since the 428local SCB space serves as a cache for disconnected transactions, the 429more SCB space available, the less host bus traffic consumed saving 430and restoring SCB data. 431.Sh SEE ALSO 432.Xr aha 4 , 433.Xr ahb 4 , 434.Xr cd 4 , 435.Xr ch 4 , 436.Xr intro 4 , 437.Xr scsi 4 , 438.Xr sd 4 , 439.Xr st 4 440.Sh HISTORY 441The 442.Nm 443driver appeared in 444.Fx 2.0 445and 446.Nx 1.1 . 447.Sh AUTHORS 448The 449.Nm 450driver, the 451.Tn AIC7xxx 452sequencer-code assembler, 453and the firmware running on the aic7xxx chips was written by 454.An Justin T. Gibbs . 455.Nx 456porting is done by Stefan Grefen, Charles M. Hannum, 457Michael Graff, Jason R. Thorpe, Pete Bentley, 458Frank van der Linden and Noriyuki Soda. 459.Sh BUGS 460Some 461.Tn Quantum 462drives (at least the Empire 2100 and 1080s) will not run on an 463.Tn AIC7870 464Rev B in synchronous mode at 10MHz. Controllers with this problem have a 46542 MHz clock crystal on them and run slightly above 10MHz. This confuses 466the drive and hangs the bus. Setting a maximum synchronous negotiation rate 467of 8MHz in the 468.Tn SCSI-Select 469utility will allow normal operation. 470.Pp 471Double Transition clocking is not yet supported for Ultra160 controllers. 472This limits these controllers to 40MHz or 80MB/s. 473.Pp 474.ie 0 \{ 475Although the Ultra2 and Ultra160 products have sufficient instruction 476ram space to support both the initiator and target roles concurrently, 477this configuration is disabled in favor of allowing the target role 478to respond on multiple target ids. A method for configuring dual 479role mode should be provided. 480.Pp 481Tagged Queuing is not supported in target mode. 482.Pp 483Reselection in target mode fails to function correctly on all high 484voltage differential boards as shipped by Adaptec. Information on 485how to modify HVD board to work correctly in target mode is available 486from Adaptec. 487\} 488\{Target mode is not supported on 489.Nx 490version of this driver.\} 491