eata.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

/*
 *      eata.c - Low-level driver for EATA/DMA SCSI host adapters.
 *
 *      26 Jul 1998 Rev. 4.33 for linux 2.0.35 and 2.1.111
 *        + Added command line option (rs:[y|n]) to reverse the scan order
 *          of PCI boards. The default is rs:y, which reverses the BIOS order
 *          while registering PCI boards. The default value rs:y generates
 *          the same order of all previous revisions of this driver.
 *          Pls. note that "BIOS order" might have been reversed itself
 *          after the 2.1.9x PCI modifications in the linux kernel.
 *          The rs value is ignored when the explicit list of addresses
 *          is used by the "eata=port0,port1,..." command line option.
 *        + Added command line option (et:[y|n]) to force use of extended
 *          translation (255 heads, 63 sectors) as disk geometry.
 *          The default is et:n, which uses the disk geometry returned
 *          by scsicam_bios_param. The default value et:n is compatible with
 *          all previous revisions of this driver.
 *
 *      28 May 1998 Rev. 4.32 for linux 2.0.33 and 2.1.104
 *          Increased busy timeout from 10 msec. to 200 msec. while
 *          processing interrupts.
 *
 *      16 May 1998 Rev. 4.31 for linux 2.0.33 and 2.1.102
 *          Improved abort handling during the eh recovery process.
 *
 *      13 May 1998 Rev. 4.30 for linux 2.0.33 and 2.1.101
 *          The driver is now fully SMP safe, including the
 *          abort and reset routines.
 *          Added command line options (eh:[y|n]) to choose between
 *          new_eh_code and the old scsi code.
 *          If linux version >= 2.1.101 the default is eh:y, while the eh
 *          option is ignored for previous releases and the old scsi code
 *          is used.
 *
 *      18 Apr 1998 Rev. 4.20 for linux 2.0.33 and 2.1.97
 *          Reworked interrupt handler.
 *
 *      11 Apr 1998 rev. 4.05 for linux 2.0.33 and 2.1.95
 *          Major reliability improvement: when a batch with overlapping
 *          requests is detected, requests are queued one at a time
 *          eliminating any possible board or drive reordering.
 *
 *      10 Apr 1998 rev. 4.04 for linux 2.0.33 and 2.1.95
 *          Improved SMP support (if linux version >= 2.1.95).
 *
 *       9 Apr 1998 rev. 4.03 for linux 2.0.33 and 2.1.94
 *          Added support for new PCI code and IO-APIC remapping of irqs.
 *          Performance improvement: when sequential i/o is detected,
 *          always use direct sort instead of reverse sort.
 *
 *       4 Apr 1998 rev. 4.02 for linux 2.0.33 and 2.1.92
 *          io_port is now unsigned long.
 *
 *      17 Mar 1998 rev. 4.01 for linux 2.0.33 and 2.1.88
 *          Use new scsi error handling code (if linux version >= 2.1.88).
 *          Use new interrupt code.
 *
 *      12 Sep 1997 rev. 3.11 for linux 2.0.30 and 2.1.55
 *          Use of udelay inside the wait loops to avoid timeout
 *          problems with fast cpus.
 *          Removed check about useless calls to the interrupt service
 *          routine (reported on SMP systems only).
 *          At initialization time "sorted/unsorted" is displayed instead
 *          of "linked/unlinked" to reinforce the fact that "linking" is
 *          nothing but "elevator sorting" in the actual implementation.
 *
 *      17 May 1997 rev. 3.10 for linux 2.0.30 and 2.1.38
 *          Use of serial_number_at_timeout in abort and reset processing.
 *          Use of the __initfunc and __initdata macro in setup code.
 *          Minor cleanups in the list_statistics code.
 *          Increased controller busy timeout in order to better support
 *          slow SCSI devices.
 *
 *      24 Feb 1997 rev. 3.00 for linux 2.0.29 and 2.1.26
 *          When loading as a module, parameter passing is now supported
 *          both in 2.0 and in 2.1 style.
 *          Fixed data transfer direction for some SCSI opcodes.
 *          Immediate acknowledge to request sense commands.
 *          Linked commands to each disk device are now reordered by elevator
 *          sorting. Rare cases in which reordering of write requests could
 *          cause wrong results are managed.
 *          Fixed spurious timeouts caused by long simple queue tag sequences.
 *          New command line option (tm:[0-3]) to choose the type of tags:
 *          0 -> mixed (default); 1 -> simple; 2 -> head; 3 -> ordered.
 *
 *      18 Jan 1997 rev. 2.60 for linux 2.1.21 and 2.0.28
 *          Added command line options to enable/disable linked commands
 *          (lc:[y|n]), tagged commands (tc:[y|n]) and to set the max queue
 *          depth (mq:xx). Default is "eata=lc:n,tc:n,mq:16".
 *          Improved command linking.
 *          Documented how to setup RAID-0 with DPT SmartRAID boards.
 *
 *       8 Jan 1997 rev. 2.50 for linux 2.1.20 and 2.0.27
 *          Added linked command support.
 *          Improved detection of PCI boards using ISA base addresses.
 *
 *       3 Dec 1996 rev. 2.40 for linux 2.1.14 and 2.0.27
 *          Added support for tagged commands and queue depth adjustment.
 *
 *      22 Nov 1996 rev. 2.30 for linux 2.1.12 and 2.0.26
 *          When CONFIG_PCI is defined, BIOS32 is used to include in the
 *          list of i/o ports to be probed all the PCI SCSI controllers.
 *          The list of i/o ports to be probed can be overwritten by the
 *          "eata=port0,port1,...." boot command line option.
 *          Scatter/gather lists are now allocated by a number of kmalloc
 *          calls, in order to avoid the previous size limit of 64Kb.
 *
 *      16 Nov 1996 rev. 2.20 for linux 2.1.10 and 2.0.25
 *          Added support for EATA 2.0C, PCI, multichannel and wide SCSI.
 *
 *      27 Sep 1996 rev. 2.12 for linux 2.1.0
 *          Portability cleanups (virtual/bus addressing, little/big endian
 *          support).
 *
 *      09 Jul 1996 rev. 2.11 for linux 2.0.4
 *          Number of internal retries is now limited.
 *
 *      16 Apr 1996 rev. 2.10 for linux 1.3.90
 *          New argument "reset_flags" to the reset routine.
 *
 *       6 Jul 1995 rev. 2.01 for linux 1.3.7
 *          Update required by the new /proc/scsi support.
 *
 *      11 Mar 1995 rev. 2.00 for linux 1.2.0
 *          Fixed a bug which prevented media change detection for removable
 *          disk drives.
 *
 *      23 Feb 1995 rev. 1.18 for linux 1.1.94
 *          Added a check for scsi_register returning NULL.
 *
 *      11 Feb 1995 rev. 1.17 for linux 1.1.91
 *          Now DEBUG_RESET is disabled by default.
 *          Register a board even if it does not assert DMA protocol support
 *          (DPT SK2011B does not report correctly the dmasup bit).
 *
 *       9 Feb 1995 rev. 1.16 for linux 1.1.90
 *          Use host->wish_block instead of host->block.
 *          New list of Data Out SCSI commands.
 *
 *       8 Feb 1995 rev. 1.15 for linux 1.1.89
 *          Cleared target_time_out counter while performing a reset.
 *          All external symbols renamed to avoid possible name conflicts.
 *
 *      28 Jan 1995 rev. 1.14 for linux 1.1.86
 *          Added module support.
 *          Log and do a retry when a disk drive returns a target status
 *          different from zero on a recovered error.
 *
 *      24 Jan 1995 rev. 1.13 for linux 1.1.85
 *          Use optimized board configuration, with a measured performance
 *          increase in the range 10%-20% on i/o throughput.
 *
 *      16 Jan 1995 rev. 1.12 for linux 1.1.81
 *          Fix mscp structure comments (no functional change).
 *          Display a message if check_region detects a port address
 *          already in use.
 *
 *      17 Dec 1994 rev. 1.11 for linux 1.1.74
 *          Use the scsicam_bios_param routine. This allows an easy
 *          migration path from disk partition tables created using
 *          different SCSI drivers and non optimal disk geometry.
 *
 *      15 Dec 1994 rev. 1.10 for linux 1.1.74
 *          Added support for ISA EATA boards (DPT PM2011, DPT PM2021).
 *          The host->block flag is set for all the detected ISA boards.
 *          The detect routine no longer enforces LEVEL triggering
 *          for EISA boards, it just prints a warning message.
 *
 *      30 Nov 1994 rev. 1.09 for linux 1.1.68
 *          Redo i/o on target status CHECK_CONDITION for TYPE_DISK only.
 *          Added optional support for using a single board at a time.
 *
 *      18 Nov 1994 rev. 1.08 for linux 1.1.64
 *          Forces sg_tablesize = 64 and can_queue = 64 if these
 *          values are not correctly detected (DPT PM2012).
 *
 *      14 Nov 1994 rev. 1.07 for linux 1.1.63  Final BETA release.
 *      04 Aug 1994 rev. 1.00 for linux 1.1.39  First BETA release.
 *
 *
 *          This driver is based on the CAM (Common Access Method Committee)
 *          EATA (Enhanced AT Bus Attachment) rev. 2.0A, using DMA protocol.
 *
 *  Copyright (C) 1994-1998 Dario Ballabio ([e-mail])
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that redistributions of source
 *  code retain the above copyright notice and this comment without
 *  modification.
 *
 */

/*
 *
 *  Here is a brief description of the DPT SCSI host adapters.
 *  All these boards provide an EATA/DMA compatible programming interface
 *  and are fully supported by this driver in any configuration, including
 *  multiple SCSI channels:
 *
 *  PM2011B/9X -  Entry Level ISA
 *  PM2021A/9X -  High Performance ISA
 *  PM2012A       Old EISA
 *  PM2012B       Old EISA
 *  PM2022A/9X -  Entry Level EISA
 *  PM2122A/9X -  High Performance EISA
 *  PM2322A/9X -  Extra High Performance EISA
 *  PM3021     -  SmartRAID Adapter for ISA
 *  PM3222     -  SmartRAID Adapter for EISA (PM3222W is 16-bit wide SCSI)
 *  PM3224     -  SmartRAID Adapter for PCI  (PM3224W is 16-bit wide SCSI)
 *
 *  The above list is just an indication: as a matter of fact all DPT
 *  boards using the EATA/DMA protocol are supported by this driver,
 *  since they use exactely the same programming interface.
 *
 *  The DPT PM2001 provides only the EATA/PIO interface and hence is not
 *  supported by this driver.
 *
 *  This code has been tested with up to 3 Distributed Processing Technology
 *  PM2122A/9X (DPT SCSI BIOS v002.D1, firmware v05E.0) EISA controllers,
 *  in any combination of private and shared IRQ.
 *  PCI support has been tested using up to 2 DPT PM3224W (DPT SCSI BIOS
 *  v003.D0, firmware v07G.0).
 *
 *  DPT SmartRAID boards support "Hardware Array" - a group of disk drives
 *  which are all members of the same RAID-0, RAID-1 or RAID-5 array implemented
 *  in host adapter hardware. Hardware Arrays are fully compatible with this
 *  driver, since they look to it as a single disk drive.
 *
 *  WARNING: to create a RAID-0 "Hardware Array" you must select "Other Unix"
 *  as the current OS in the DPTMGR "Initial System Installation" menu.
 *  Otherwise RAID-0 is generated as an "Array Group" (i.e. software RAID-0),
 *  which is not supported by the actual SCSI subsystem.
 *  To get the "Array Group" functionality, the Linux MD driver must be used
 *  instead of the DPT "Array Group" feature.
 *
 *  Multiple ISA, EISA and PCI boards can be configured in the same system.
 *  It is suggested to put all the EISA boards on the same IRQ level, all
 *  the PCI  boards on another IRQ level, while ISA boards cannot share
 *  interrupts.
 *
 *  If you configure multiple boards on the same IRQ, the interrupt must
 *  be _level_ triggered (not _edge_ triggered).
 *
 *  This driver detects EATA boards by probes at fixed port addresses,
 *  so no BIOS32 or PCI BIOS support is required.
 *  The suggested way to detect a generic EATA PCI board is to force on it
 *  any unused EISA address, even if there are other controllers on the EISA
 *  bus, or even if you system has no EISA bus at all.
 *  Do not force any ISA address on EATA PCI boards.
 *
 *  If PCI bios support is configured into the kernel, BIOS32 is used to
 *  include in the list of i/o ports to be probed all the PCI SCSI controllers.
 *
 *  Due to a DPT BIOS "feature", it might not be possible to force an EISA
 *  address on more then a single DPT PCI board, so in this case you have to
 *  let the PCI BIOS assign the addresses.
 *
 *  The sequence of detection probes is:
 *
 *  - ISA 0x1F0;
 *  - PCI SCSI controllers (only if BIOS32 is available);
 *  - EISA/PCI 0x1C88 through 0xFC88 (corresponding to EISA slots 1 to 15);
 *  - ISA  0x170, 0x230, 0x330.
 *
 *  The above list of detection probes can be totally replaced by the
 *  boot command line option: "eata=port0,port1,port2,...", where the
 *  port0, port1... arguments are ISA/EISA/PCI addresses to be probed.
 *  For example using "eata=0x7410,0x7450,0x230", the driver probes
 *  only the two PCI addresses 0x7410 and 0x7450 and the ISA address 0x230,
 *  in this order; "eata=0" totally disables this driver.
 *
 *  After the optional list of detection probes, other possible command line
 *  options are:
 *
 *  eh:y  use new scsi code (linux 2.2 only);
 *  eh:n  use old scsi code;
 *  et:y  force use of extended translation (255 heads, 63 sectors);
 *  et:n  use disk geometry detected by scsicam_bios_param;
 *  rs:y  reverse scan order while detecting PCI boards;
 *  rs:n  use BIOS order while detecting PCI boards;
 *  lc:y  enables linked commands;
 *  lc:n  disables linked commands;
 *  tc:y  enables tagged commands;
 *  tc:n  disables tagged commands;
 *  tm:0  use head/simple/ordered queue tag sequences;
 *  tm:1  use only simple queue tags;
 *  tm:2  use only head of queue tags;
 *  tm:3  use only ordered queue tags;
 *  mq:xx set the max queue depth to the value xx (2 <= xx <= 32).
 *
 *  The default value is: "eata=lc:n,tc:n,mq:16,tm:0,et:n,rs:n".
 *  An example using the list of detection probes could be:
 *  "eata=0x7410,0x230,lc:y,tc:n,mq:4,eh:n,et:n".
 *
 *  When loading as a module, parameters can be specified as well.
 *  The above example would be (use 1 in place of y and 0 in place of n):
 *
 *  modprobe eata io_port=0x7410,0x230 linked_comm=1 tagged_comm=0 \
 *                max_queue_depth=4 tag_mode=0 use_new_eh_code=0 \
 *                ext_tran=0 rev_scan=1
 *
 *  ----------------------------------------------------------------------------
 *  In this implementation, linked commands are designed to work with any DISK
 *  or CD-ROM, since this linking has only the intent of clustering (time-wise)
 *  and reordering by elevator sorting commands directed to each device,
 *  without any relation with the actual SCSI protocol between the controller
 *  and the device.
 *  If Q is the queue depth reported at boot time for each device (also named
 *  cmds/lun) and Q > 2, whenever there is already an active command to the
 *  device all other commands to the same device  (up to Q-1) are kept waiting
 *  in the elevator sorting queue. When the active command completes, the
 *  commands in this queue are sorted by sector address. The sort is chosen
 *  between increasing or decreasing by minimizing the seek distance between
 *  the sector of the commands just completed and the sector of the first
 *  command in the list to be sorted.
 *  Trivial math assures that the unsorted average seek distance when doing
 *  random seeks over S sectors is S/3.
 *  When (Q-1) requests are uniformly distributed over S sectors, the average
 *  distance between two adjacent requests is S/((Q-1) + 1), so the sorted
 *  average seek distance for (Q-1) random requests over S sectors is S/Q.
 *  The elevator sorting hence divides the seek distance by a factor Q/3.
 *  The above pure geometric remarks are valid in all cases and the
 *  driver effectively reduces the seek distance by the predicted factor
 *  when there are Q concurrent read i/o operations on the device, but this
 *  does not necessarily results in a noticeable performance improvement:
 *  your mileage may vary....
 *
 *  Note: command reordering inside a batch of queued commands could cause
 *        wrong results only if there is at least one write request and the
 *        intersection (sector-wise) of all requests is not empty.
 *        When the driver detects a batch including overlapping requests
 *        (a really rare event) strict serial (pid) order is enforced.
 *  ----------------------------------------------------------------------------
 *  The extended translation option (et:y) is useful when using large physical
 *  disks/arrays. It could also be useful when switching between Adaptec boards
 *  and DPT boards without reformatting the disk.
 *  When a boot disk is partitioned with extended translation, in order to
 *  be able to boot it with a DPT board is could be necessary to add to
 *  lilo.conf additional commands as in the following example:
 *
 *  fix-table
 *  disk=/dev/sda bios=0x80 sectors=63 heads=128 cylindres=546
 *
 *  where the above geometry should be replaced with the one reported at
 *  power up by the DPT controller.
 *  ----------------------------------------------------------------------------
 *
 *  The boards are named EATA0, EATA1,... according to the detection order.
 *
 *  In order to support multiple ISA boards in a reliable way,
 *  the driver sets host->wish_block = TRUE for all ISA boards.
 */

#include <linux/version.h>

#define LinuxVersionCode(v, p, s) (((v)<<16)+((p)<<8)+(s))
#define MAX_INT_PARAM 10

#if defined(MODULE)
#include <linux/module.h>

#if LINUX_VERSION_CODE >= LinuxVersionCode(2,1,26)
MODULE_PARM(io_port, "1-" __MODULE_STRING(MAX_INT_PARAM) "i");
MODULE_PARM(linked_comm, "i");
MODULE_PARM(tagged_comm, "i");
MODULE_PARM(link_statistics, "i");
MODULE_PARM(max_queue_depth, "i");
MODULE_PARM(tag_mode, "i");
MODULE_PARM(use_new_eh_code, "i");
MODULE_PARM(ext_tran, "i");
MODULE_PARM(rev_scan, "i");
MODULE_AUTHOR("Dario Ballabio");
#endif

#endif

#include <linux/string.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/byteorder.h>
#include <linux/proc_fs.h>
#include <linux/blk.h>
#include "scsi.h"
#include "hosts.h"
#include "sd.h"