cachepc-linux

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wd33c93.c (67105B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3 * Copyright (c) 1996 John Shifflett, GeoLog Consulting
      4 *    john@geolog.com
      5 *    jshiffle@netcom.com
      6 */
      7
      8/*
      9 * Drew Eckhardt's excellent 'Generic NCR5380' sources from Linux-PC
     10 * provided much of the inspiration and some of the code for this
     11 * driver. Everything I know about Amiga DMA was gleaned from careful
     12 * reading of Hamish Mcdonald's original wd33c93 driver; in fact, I
     13 * borrowed shamelessly from all over that source. Thanks Hamish!
     14 *
     15 * _This_ driver is (I feel) an improvement over the old one in
     16 * several respects:
     17 *
     18 *    -  Target Disconnection/Reconnection  is now supported. Any
     19 *          system with more than one device active on the SCSI bus
     20 *          will benefit from this. The driver defaults to what I
     21 *          call 'adaptive disconnect' - meaning that each command
     22 *          is evaluated individually as to whether or not it should
     23 *          be run with the option to disconnect/reselect (if the
     24 *          device chooses), or as a "SCSI-bus-hog".
     25 *
     26 *    -  Synchronous data transfers are now supported. Because of
     27 *          a few devices that choke after telling the driver that
     28 *          they can do sync transfers, we don't automatically use
     29 *          this faster protocol - it can be enabled via the command-
     30 *          line on a device-by-device basis.
     31 *
     32 *    -  Runtime operating parameters can now be specified through
     33 *       the 'amiboot' or the 'insmod' command line. For amiboot do:
     34 *          "amiboot [usual stuff] wd33c93=blah,blah,blah"
     35 *       The defaults should be good for most people. See the comment
     36 *       for 'setup_strings' below for more details.
     37 *
     38 *    -  The old driver relied exclusively on what the Western Digital
     39 *          docs call "Combination Level 2 Commands", which are a great
     40 *          idea in that the CPU is relieved of a lot of interrupt
     41 *          overhead. However, by accepting a certain (user-settable)
     42 *          amount of additional interrupts, this driver achieves
     43 *          better control over the SCSI bus, and data transfers are
     44 *          almost as fast while being much easier to define, track,
     45 *          and debug.
     46 *
     47 *
     48 * TODO:
     49 *       more speed. linked commands.
     50 *
     51 *
     52 * People with bug reports, wish-lists, complaints, comments,
     53 * or improvements are asked to pah-leeez email me (John Shifflett)
     54 * at john@geolog.com or jshiffle@netcom.com! I'm anxious to get
     55 * this thing into as good a shape as possible, and I'm positive
     56 * there are lots of lurking bugs and "Stupid Places".
     57 *
     58 * Updates:
     59 *
     60 * Added support for pre -A chips, which don't have advanced features
     61 * and will generate CSR_RESEL rather than CSR_RESEL_AM.
     62 *	Richard Hirst <richard@sleepie.demon.co.uk>  August 2000
     63 *
     64 * Added support for Burst Mode DMA and Fast SCSI. Enabled the use of
     65 * default_sx_per for asynchronous data transfers. Added adjustment
     66 * of transfer periods in sx_table to the actual input-clock.
     67 *  peter fuerst <post@pfrst.de>  February 2007
     68 */
     69
     70#include <linux/module.h>
     71
     72#include <linux/string.h>
     73#include <linux/delay.h>
     74#include <linux/init.h>
     75#include <linux/interrupt.h>
     76#include <linux/blkdev.h>
     77
     78#include <scsi/scsi.h>
     79#include <scsi/scsi_cmnd.h>
     80#include <scsi/scsi_device.h>
     81#include <scsi/scsi_host.h>
     82
     83#include <asm/irq.h>
     84
     85#include "wd33c93.h"
     86
     87#define optimum_sx_per(hostdata) (hostdata)->sx_table[1].period_ns
     88
     89
     90#define WD33C93_VERSION    "1.26++"
     91#define WD33C93_DATE       "10/Feb/2007"
     92
     93MODULE_AUTHOR("John Shifflett");
     94MODULE_DESCRIPTION("Generic WD33C93 SCSI driver");
     95MODULE_LICENSE("GPL");
     96
     97/*
     98 * 'setup_strings' is a single string used to pass operating parameters and
     99 * settings from the kernel/module command-line to the driver. 'setup_args[]'
    100 * is an array of strings that define the compile-time default values for
    101 * these settings. If Linux boots with an amiboot or insmod command-line,
    102 * those settings are combined with 'setup_args[]'. Note that amiboot
    103 * command-lines are prefixed with "wd33c93=" while insmod uses a
    104 * "setup_strings=" prefix. The driver recognizes the following keywords
    105 * (lower case required) and arguments:
    106 *
    107 * -  nosync:bitmask -bitmask is a byte where the 1st 7 bits correspond with
    108 *                    the 7 possible SCSI devices. Set a bit to negotiate for
    109 *                    asynchronous transfers on that device. To maintain
    110 *                    backwards compatibility, a command-line such as
    111 *                    "wd33c93=255" will be automatically translated to
    112 *                    "wd33c93=nosync:0xff".
    113 * -  nodma:x        -x = 1 to disable DMA, x = 0 to enable it. Argument is
    114 *                    optional - if not present, same as "nodma:1".
    115 * -  period:ns      -ns is the minimum # of nanoseconds in a SCSI data transfer
    116 *                    period. Default is 500; acceptable values are 250 - 1000.
    117 * -  disconnect:x   -x = 0 to never allow disconnects, 2 to always allow them.
    118 *                    x = 1 does 'adaptive' disconnects, which is the default
    119 *                    and generally the best choice.
    120 * -  debug:x        -If 'DEBUGGING_ON' is defined, x is a bit mask that causes
    121 *                    various types of debug output to printed - see the DB_xxx
    122 *                    defines in wd33c93.h
    123 * -  clock:x        -x = clock input in MHz for WD33c93 chip. Normal values
    124 *                    would be from 8 through 20. Default is 8.
    125 * -  burst:x        -x = 1 to use Burst Mode (or Demand-Mode) DMA, x = 0 to use
    126 *                    Single Byte DMA, which is the default. Argument is
    127 *                    optional - if not present, same as "burst:1".
    128 * -  fast:x         -x = 1 to enable Fast SCSI, which is only effective with
    129 *                    input-clock divisor 4 (WD33C93_FS_16_20), x = 0 to disable
    130 *                    it, which is the default.  Argument is optional - if not
    131 *                    present, same as "fast:1".
    132 * -  next           -No argument. Used to separate blocks of keywords when
    133 *                    there's more than one host adapter in the system.
    134 *
    135 * Syntax Notes:
    136 * -  Numeric arguments can be decimal or the '0x' form of hex notation. There
    137 *    _must_ be a colon between a keyword and its numeric argument, with no
    138 *    spaces.
    139 * -  Keywords are separated by commas, no spaces, in the standard kernel
    140 *    command-line manner.
    141 * -  A keyword in the 'nth' comma-separated command-line member will overwrite
    142 *    the 'nth' element of setup_args[]. A blank command-line member (in
    143 *    other words, a comma with no preceding keyword) will _not_ overwrite
    144 *    the corresponding setup_args[] element.
    145 * -  If a keyword is used more than once, the first one applies to the first
    146 *    SCSI host found, the second to the second card, etc, unless the 'next'
    147 *    keyword is used to change the order.
    148 *
    149 * Some amiboot examples (for insmod, use 'setup_strings' instead of 'wd33c93'):
    150 * -  wd33c93=nosync:255
    151 * -  wd33c93=nodma
    152 * -  wd33c93=nodma:1
    153 * -  wd33c93=disconnect:2,nosync:0x08,period:250
    154 * -  wd33c93=debug:0x1c
    155 */
    156
    157/* Normally, no defaults are specified */
    158static char *setup_args[] = { "", "", "", "", "", "", "", "", "", "" };
    159
    160static char *setup_strings;
    161module_param(setup_strings, charp, 0);
    162
    163static void wd33c93_execute(struct Scsi_Host *instance);
    164
    165#ifdef CONFIG_WD33C93_PIO
    166static inline uchar
    167read_wd33c93(const wd33c93_regs regs, uchar reg_num)
    168{
    169	uchar data;
    170
    171	outb(reg_num, regs.SASR);
    172	data = inb(regs.SCMD);
    173	return data;
    174}
    175
    176static inline unsigned long
    177read_wd33c93_count(const wd33c93_regs regs)
    178{
    179	unsigned long value;
    180
    181	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
    182	value = inb(regs.SCMD) << 16;
    183	value |= inb(regs.SCMD) << 8;
    184	value |= inb(regs.SCMD);
    185	return value;
    186}
    187
    188static inline uchar
    189read_aux_stat(const wd33c93_regs regs)
    190{
    191	return inb(regs.SASR);
    192}
    193
    194static inline void
    195write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
    196{
    197      outb(reg_num, regs.SASR);
    198      outb(value, regs.SCMD);
    199}
    200
    201static inline void
    202write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
    203{
    204	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
    205	outb((value >> 16) & 0xff, regs.SCMD);
    206	outb((value >> 8) & 0xff, regs.SCMD);
    207	outb( value & 0xff, regs.SCMD);
    208}
    209
    210#define write_wd33c93_cmd(regs, cmd) \
    211	write_wd33c93((regs), WD_COMMAND, (cmd))
    212
    213static inline void
    214write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
    215{
    216	int i;
    217
    218	outb(WD_CDB_1, regs.SASR);
    219	for (i=0; i<len; i++)
    220		outb(cmnd[i], regs.SCMD);
    221}
    222
    223#else /* CONFIG_WD33C93_PIO */
    224static inline uchar
    225read_wd33c93(const wd33c93_regs regs, uchar reg_num)
    226{
    227	*regs.SASR = reg_num;
    228	mb();
    229	return (*regs.SCMD);
    230}
    231
    232static unsigned long
    233read_wd33c93_count(const wd33c93_regs regs)
    234{
    235	unsigned long value;
    236
    237	*regs.SASR = WD_TRANSFER_COUNT_MSB;
    238	mb();
    239	value = *regs.SCMD << 16;
    240	value |= *regs.SCMD << 8;
    241	value |= *regs.SCMD;
    242	mb();
    243	return value;
    244}
    245
    246static inline uchar
    247read_aux_stat(const wd33c93_regs regs)
    248{
    249	return *regs.SASR;
    250}
    251
    252static inline void
    253write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
    254{
    255	*regs.SASR = reg_num;
    256	mb();
    257	*regs.SCMD = value;
    258	mb();
    259}
    260
    261static void
    262write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
    263{
    264	*regs.SASR = WD_TRANSFER_COUNT_MSB;
    265	mb();
    266	*regs.SCMD = value >> 16;
    267	*regs.SCMD = value >> 8;
    268	*regs.SCMD = value;
    269	mb();
    270}
    271
    272static inline void
    273write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
    274{
    275	*regs.SASR = WD_COMMAND;
    276	mb();
    277	*regs.SCMD = cmd;
    278	mb();
    279}
    280
    281static inline void
    282write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
    283{
    284	int i;
    285
    286	*regs.SASR = WD_CDB_1;
    287	for (i = 0; i < len; i++)
    288		*regs.SCMD = cmnd[i];
    289}
    290#endif /* CONFIG_WD33C93_PIO */
    291
    292static inline uchar
    293read_1_byte(const wd33c93_regs regs)
    294{
    295	uchar asr;
    296	uchar x = 0;
    297
    298	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
    299	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO | 0x80);
    300	do {
    301		asr = read_aux_stat(regs);
    302		if (asr & ASR_DBR)
    303			x = read_wd33c93(regs, WD_DATA);
    304	} while (!(asr & ASR_INT));
    305	return x;
    306}
    307
    308static int
    309round_period(unsigned int period, const struct sx_period *sx_table)
    310{
    311	int x;
    312
    313	for (x = 1; sx_table[x].period_ns; x++) {
    314		if ((period <= sx_table[x - 0].period_ns) &&
    315		    (period > sx_table[x - 1].period_ns)) {
    316			return x;
    317		}
    318	}
    319	return 7;
    320}
    321
    322/*
    323 * Calculate Synchronous Transfer Register value from SDTR code.
    324 */
    325static uchar
    326calc_sync_xfer(unsigned int period, unsigned int offset, unsigned int fast,
    327               const struct sx_period *sx_table)
    328{
    329	/* When doing Fast SCSI synchronous data transfers, the corresponding
    330	 * value in 'sx_table' is two times the actually used transfer period.
    331	 */
    332	uchar result;
    333
    334	if (offset && fast) {
    335		fast = STR_FSS;
    336		period *= 2;
    337	} else {
    338		fast = 0;
    339	}
    340	period *= 4;		/* convert SDTR code to ns */
    341	result = sx_table[round_period(period,sx_table)].reg_value;
    342	result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF;
    343	result |= fast;
    344	return result;
    345}
    346
    347/*
    348 * Calculate SDTR code bytes [3],[4] from period and offset.
    349 */
    350static inline void
    351calc_sync_msg(unsigned int period, unsigned int offset, unsigned int fast,
    352                uchar  msg[2])
    353{
    354	/* 'period' is a "normal"-mode value, like the ones in 'sx_table'. The
    355	 * actually used transfer period for Fast SCSI synchronous data
    356	 * transfers is half that value.
    357	 */
    358	period /= 4;
    359	if (offset && fast)
    360		period /= 2;
    361	msg[0] = period;
    362	msg[1] = offset;
    363}
    364
    365static int wd33c93_queuecommand_lck(struct scsi_cmnd *cmd)
    366{
    367	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
    368	struct WD33C93_hostdata *hostdata;
    369	struct scsi_cmnd *tmp;
    370
    371	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
    372
    373	DB(DB_QUEUE_COMMAND,
    374	   printk("Q-%d-%02x( ", cmd->device->id, cmd->cmnd[0]))
    375
    376/* Set up a few fields in the scsi_cmnd structure for our own use:
    377 *  - host_scribble is the pointer to the next cmd in the input queue
    378 *  - result is what you'd expect
    379 */
    380	cmd->host_scribble = NULL;
    381	cmd->result = 0;
    382
    383/* We use the Scsi_Pointer structure that's included with each command
    384 * as a scratchpad (as it's intended to be used!). The handy thing about
    385 * the SCp.xxx fields is that they're always associated with a given
    386 * cmd, and are preserved across disconnect-reselect. This means we
    387 * can pretty much ignore SAVE_POINTERS and RESTORE_POINTERS messages
    388 * if we keep all the critical pointers and counters in SCp:
    389 *  - SCp.ptr is the pointer into the RAM buffer
    390 *  - SCp.this_residual is the size of that buffer
    391 *  - SCp.buffer points to the current scatter-gather buffer
    392 *  - SCp.buffers_residual tells us how many S.G. buffers there are
    393 *  - SCp.have_data_in is not used
    394 *  - SCp.sent_command is not used
    395 *  - SCp.phase records this command's SRCID_ER bit setting
    396 */
    397
    398	if (scsi_bufflen(cmd)) {
    399		scsi_pointer->buffer = scsi_sglist(cmd);
    400		scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1;
    401		scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
    402		scsi_pointer->this_residual = scsi_pointer->buffer->length;
    403	} else {
    404		scsi_pointer->buffer = NULL;
    405		scsi_pointer->buffers_residual = 0;
    406		scsi_pointer->ptr = NULL;
    407		scsi_pointer->this_residual = 0;
    408	}
    409
    410/* WD docs state that at the conclusion of a "LEVEL2" command, the
    411 * status byte can be retrieved from the LUN register. Apparently,
    412 * this is the case only for *uninterrupted* LEVEL2 commands! If
    413 * there are any unexpected phases entered, even if they are 100%
    414 * legal (different devices may choose to do things differently),
    415 * the LEVEL2 command sequence is exited. This often occurs prior
    416 * to receiving the status byte, in which case the driver does a
    417 * status phase interrupt and gets the status byte on its own.
    418 * While such a command can then be "resumed" (ie restarted to
    419 * finish up as a LEVEL2 command), the LUN register will NOT be
    420 * a valid status byte at the command's conclusion, and we must
    421 * use the byte obtained during the earlier interrupt. Here, we
    422 * preset SCp.Status to an illegal value (0xff) so that when
    423 * this command finally completes, we can tell where the actual
    424 * status byte is stored.
    425 */
    426
    427	scsi_pointer->Status = ILLEGAL_STATUS_BYTE;
    428
    429	/*
    430	 * Add the cmd to the end of 'input_Q'. Note that REQUEST SENSE
    431	 * commands are added to the head of the queue so that the desired
    432	 * sense data is not lost before REQUEST_SENSE executes.
    433	 */
    434
    435	spin_lock_irq(&hostdata->lock);
    436
    437	if (!(hostdata->input_Q) || (cmd->cmnd[0] == REQUEST_SENSE)) {
    438		cmd->host_scribble = (uchar *) hostdata->input_Q;
    439		hostdata->input_Q = cmd;
    440	} else {		/* find the end of the queue */
    441		for (tmp = (struct scsi_cmnd *) hostdata->input_Q;
    442		     tmp->host_scribble;
    443		     tmp = (struct scsi_cmnd *) tmp->host_scribble) ;
    444		tmp->host_scribble = (uchar *) cmd;
    445	}
    446
    447/* We know that there's at least one command in 'input_Q' now.
    448 * Go see if any of them are runnable!
    449 */
    450
    451	wd33c93_execute(cmd->device->host);
    452
    453	DB(DB_QUEUE_COMMAND, printk(")Q "))
    454
    455	spin_unlock_irq(&hostdata->lock);
    456	return 0;
    457}
    458
    459DEF_SCSI_QCMD(wd33c93_queuecommand)
    460
    461/*
    462 * This routine attempts to start a scsi command. If the host_card is
    463 * already connected, we give up immediately. Otherwise, look through
    464 * the input_Q, using the first command we find that's intended
    465 * for a currently non-busy target/lun.
    466 *
    467 * wd33c93_execute() is always called with interrupts disabled or from
    468 * the wd33c93_intr itself, which means that a wd33c93 interrupt
    469 * cannot occur while we are in here.
    470 */
    471static void
    472wd33c93_execute(struct Scsi_Host *instance)
    473{
    474	struct scsi_pointer *scsi_pointer;
    475	struct WD33C93_hostdata *hostdata =
    476	    (struct WD33C93_hostdata *) instance->hostdata;
    477	const wd33c93_regs regs = hostdata->regs;
    478	struct scsi_cmnd *cmd, *prev;
    479
    480	DB(DB_EXECUTE, printk("EX("))
    481	if (hostdata->selecting || hostdata->connected) {
    482		DB(DB_EXECUTE, printk(")EX-0 "))
    483		return;
    484	}
    485
    486	/*
    487	 * Search through the input_Q for a command destined
    488	 * for an idle target/lun.
    489	 */
    490
    491	cmd = (struct scsi_cmnd *) hostdata->input_Q;
    492	prev = NULL;
    493	while (cmd) {
    494		if (!(hostdata->busy[cmd->device->id] &
    495		      (1 << (cmd->device->lun & 0xff))))
    496			break;
    497		prev = cmd;
    498		cmd = (struct scsi_cmnd *) cmd->host_scribble;
    499	}
    500
    501	/* quit if queue empty or all possible targets are busy */
    502
    503	if (!cmd) {
    504		DB(DB_EXECUTE, printk(")EX-1 "))
    505		return;
    506	}
    507
    508	/*  remove command from queue */
    509
    510	if (prev)
    511		prev->host_scribble = cmd->host_scribble;
    512	else
    513		hostdata->input_Q = (struct scsi_cmnd *) cmd->host_scribble;
    514
    515#ifdef PROC_STATISTICS
    516	hostdata->cmd_cnt[cmd->device->id]++;
    517#endif
    518
    519	/*
    520	 * Start the selection process
    521	 */
    522
    523	if (cmd->sc_data_direction == DMA_TO_DEVICE)
    524		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
    525	else
    526		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id | DSTID_DPD);
    527
    528/* Now we need to figure out whether or not this command is a good
    529 * candidate for disconnect/reselect. We guess to the best of our
    530 * ability, based on a set of hierarchical rules. When several
    531 * devices are operating simultaneously, disconnects are usually
    532 * an advantage. In a single device system, or if only 1 device
    533 * is being accessed, transfers usually go faster if disconnects
    534 * are not allowed:
    535 *
    536 * + Commands should NEVER disconnect if hostdata->disconnect =
    537 *   DIS_NEVER (this holds for tape drives also), and ALWAYS
    538 *   disconnect if hostdata->disconnect = DIS_ALWAYS.
    539 * + Tape drive commands should always be allowed to disconnect.
    540 * + Disconnect should be allowed if disconnected_Q isn't empty.
    541 * + Commands should NOT disconnect if input_Q is empty.
    542 * + Disconnect should be allowed if there are commands in input_Q
    543 *   for a different target/lun. In this case, the other commands
    544 *   should be made disconnect-able, if not already.
    545 *
    546 * I know, I know - this code would flunk me out of any
    547 * "C Programming 101" class ever offered. But it's easy
    548 * to change around and experiment with for now.
    549 */
    550
    551	scsi_pointer = WD33C93_scsi_pointer(cmd);
    552	scsi_pointer->phase = 0;	/* assume no disconnect */
    553	if (hostdata->disconnect == DIS_NEVER)
    554		goto no;
    555	if (hostdata->disconnect == DIS_ALWAYS)
    556		goto yes;
    557	if (cmd->device->type == 1)	/* tape drive? */
    558		goto yes;
    559	if (hostdata->disconnected_Q)	/* other commands disconnected? */
    560		goto yes;
    561	if (!(hostdata->input_Q))	/* input_Q empty? */
    562		goto no;
    563	for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
    564	     prev = (struct scsi_cmnd *) prev->host_scribble) {
    565		if ((prev->device->id != cmd->device->id) ||
    566		    (prev->device->lun != cmd->device->lun)) {
    567			for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
    568			     prev = (struct scsi_cmnd *) prev->host_scribble)
    569				WD33C93_scsi_pointer(prev)->phase = 1;
    570			goto yes;
    571		}
    572	}
    573
    574	goto no;
    575
    576 yes:
    577	scsi_pointer->phase = 1;
    578
    579#ifdef PROC_STATISTICS
    580	hostdata->disc_allowed_cnt[cmd->device->id]++;
    581#endif
    582
    583 no:
    584
    585	write_wd33c93(regs, WD_SOURCE_ID, scsi_pointer->phase ? SRCID_ER : 0);
    586
    587	write_wd33c93(regs, WD_TARGET_LUN, (u8)cmd->device->lun);
    588	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
    589		      hostdata->sync_xfer[cmd->device->id]);
    590	hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
    591
    592	if ((hostdata->level2 == L2_NONE) ||
    593	    (hostdata->sync_stat[cmd->device->id] == SS_UNSET)) {
    594
    595		/*
    596		 * Do a 'Select-With-ATN' command. This will end with
    597		 * one of the following interrupts:
    598		 *    CSR_RESEL_AM:  failure - can try again later.
    599		 *    CSR_TIMEOUT:   failure - give up.
    600		 *    CSR_SELECT:    success - proceed.
    601		 */
    602
    603		hostdata->selecting = cmd;
    604
    605/* Every target has its own synchronous transfer setting, kept in the
    606 * sync_xfer array, and a corresponding status byte in sync_stat[].
    607 * Each target's sync_stat[] entry is initialized to SX_UNSET, and its
    608 * sync_xfer[] entry is initialized to the default/safe value. SS_UNSET
    609 * means that the parameters are undetermined as yet, and that we
    610 * need to send an SDTR message to this device after selection is
    611 * complete: We set SS_FIRST to tell the interrupt routine to do so.
    612 * If we've been asked not to try synchronous transfers on this
    613 * target (and _all_ luns within it), we'll still send the SDTR message
    614 * later, but at that time we'll negotiate for async by specifying a
    615 * sync fifo depth of 0.
    616 */
    617		if (hostdata->sync_stat[cmd->device->id] == SS_UNSET)
    618			hostdata->sync_stat[cmd->device->id] = SS_FIRST;
    619		hostdata->state = S_SELECTING;
    620		write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
    621		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN);
    622	} else {
    623
    624		/*
    625		 * Do a 'Select-With-ATN-Xfer' command. This will end with
    626		 * one of the following interrupts:
    627		 *    CSR_RESEL_AM:  failure - can try again later.
    628		 *    CSR_TIMEOUT:   failure - give up.
    629		 *    anything else: success - proceed.
    630		 */
    631
    632		hostdata->connected = cmd;
    633		write_wd33c93(regs, WD_COMMAND_PHASE, 0);
    634
    635		/* copy command_descriptor_block into WD chip
    636		 * (take advantage of auto-incrementing)
    637		 */
    638
    639		write_wd33c93_cdb(regs, cmd->cmd_len, cmd->cmnd);
    640
    641		/* The wd33c93 only knows about Group 0, 1, and 5 commands when
    642		 * it's doing a 'select-and-transfer'. To be safe, we write the
    643		 * size of the CDB into the OWN_ID register for every case. This
    644		 * way there won't be problems with vendor-unique, audio, etc.
    645		 */
    646
    647		write_wd33c93(regs, WD_OWN_ID, cmd->cmd_len);
    648
    649		/* When doing a non-disconnect command with DMA, we can save
    650		 * ourselves a DATA phase interrupt later by setting everything
    651		 * up ahead of time.
    652		 */
    653
    654		if (scsi_pointer->phase == 0 && hostdata->no_dma == 0) {
    655			if (hostdata->dma_setup(cmd,
    656			    (cmd->sc_data_direction == DMA_TO_DEVICE) ?
    657			     DATA_OUT_DIR : DATA_IN_DIR))
    658				write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
    659			else {
    660				write_wd33c93_count(regs,
    661						scsi_pointer->this_residual);
    662				write_wd33c93(regs, WD_CONTROL,
    663					      CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
    664				hostdata->dma = D_DMA_RUNNING;
    665			}
    666		} else
    667			write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
    668
    669		hostdata->state = S_RUNNING_LEVEL2;
    670		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
    671	}
    672
    673	/*
    674	 * Since the SCSI bus can handle only 1 connection at a time,
    675	 * we get out of here now. If the selection fails, or when
    676	 * the command disconnects, we'll come back to this routine
    677	 * to search the input_Q again...
    678	 */
    679
    680	DB(DB_EXECUTE,
    681	   printk("%s)EX-2 ", scsi_pointer->phase ? "d:" : ""))
    682}
    683
    684static void
    685transfer_pio(const wd33c93_regs regs, uchar * buf, int cnt,
    686	     int data_in_dir, struct WD33C93_hostdata *hostdata)
    687{
    688	uchar asr;
    689
    690	DB(DB_TRANSFER,
    691	   printk("(%p,%d,%s:", buf, cnt, data_in_dir ? "in" : "out"))
    692
    693	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
    694	write_wd33c93_count(regs, cnt);
    695	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
    696	if (data_in_dir) {
    697		do {
    698			asr = read_aux_stat(regs);
    699			if (asr & ASR_DBR)
    700				*buf++ = read_wd33c93(regs, WD_DATA);
    701		} while (!(asr & ASR_INT));
    702	} else {
    703		do {
    704			asr = read_aux_stat(regs);
    705			if (asr & ASR_DBR)
    706				write_wd33c93(regs, WD_DATA, *buf++);
    707		} while (!(asr & ASR_INT));
    708	}
    709
    710	/* Note: we are returning with the interrupt UN-cleared.
    711	 * Since (presumably) an entire I/O operation has
    712	 * completed, the bus phase is probably different, and
    713	 * the interrupt routine will discover this when it
    714	 * responds to the uncleared int.
    715	 */
    716
    717}
    718
    719static void
    720transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd,
    721		int data_in_dir)
    722{
    723	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
    724	struct WD33C93_hostdata *hostdata;
    725	unsigned long length;
    726
    727	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
    728
    729/* Normally, you'd expect 'this_residual' to be non-zero here.
    730 * In a series of scatter-gather transfers, however, this
    731 * routine will usually be called with 'this_residual' equal
    732 * to 0 and 'buffers_residual' non-zero. This means that a
    733 * previous transfer completed, clearing 'this_residual', and
    734 * now we need to setup the next scatter-gather buffer as the
    735 * source or destination for THIS transfer.
    736 */
    737	if (!scsi_pointer->this_residual && scsi_pointer->buffers_residual) {
    738		scsi_pointer->buffer = sg_next(scsi_pointer->buffer);
    739		--scsi_pointer->buffers_residual;
    740		scsi_pointer->this_residual = scsi_pointer->buffer->length;
    741		scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
    742	}
    743	if (!scsi_pointer->this_residual) /* avoid bogus setups */
    744		return;
    745
    746	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
    747		      hostdata->sync_xfer[cmd->device->id]);
    748
    749/* 'hostdata->no_dma' is TRUE if we don't even want to try DMA.
    750 * Update 'this_residual' and 'ptr' after 'transfer_pio()' returns.
    751 */
    752
    753	if (hostdata->no_dma || hostdata->dma_setup(cmd, data_in_dir)) {
    754#ifdef PROC_STATISTICS
    755		hostdata->pio_cnt++;
    756#endif
    757		transfer_pio(regs, (uchar *) scsi_pointer->ptr,
    758			     scsi_pointer->this_residual, data_in_dir,
    759			     hostdata);
    760		length = scsi_pointer->this_residual;
    761		scsi_pointer->this_residual = read_wd33c93_count(regs);
    762		scsi_pointer->ptr += length - scsi_pointer->this_residual;
    763	}
    764
    765/* We are able to do DMA (in fact, the Amiga hardware is
    766 * already going!), so start up the wd33c93 in DMA mode.
    767 * We set 'hostdata->dma' = D_DMA_RUNNING so that when the
    768 * transfer completes and causes an interrupt, we're
    769 * reminded to tell the Amiga to shut down its end. We'll
    770 * postpone the updating of 'this_residual' and 'ptr'
    771 * until then.
    772 */
    773
    774	else {
    775#ifdef PROC_STATISTICS
    776		hostdata->dma_cnt++;
    777#endif
    778		write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
    779		write_wd33c93_count(regs, scsi_pointer->this_residual);
    780
    781		if ((hostdata->level2 >= L2_DATA) ||
    782		    (hostdata->level2 == L2_BASIC && scsi_pointer->phase == 0)) {
    783			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
    784			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
    785			hostdata->state = S_RUNNING_LEVEL2;
    786		} else
    787			write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
    788
    789		hostdata->dma = D_DMA_RUNNING;
    790	}
    791}
    792
    793void
    794wd33c93_intr(struct Scsi_Host *instance)
    795{
    796	struct scsi_pointer *scsi_pointer;
    797	struct WD33C93_hostdata *hostdata =
    798	    (struct WD33C93_hostdata *) instance->hostdata;
    799	const wd33c93_regs regs = hostdata->regs;
    800	struct scsi_cmnd *patch, *cmd;
    801	uchar asr, sr, phs, id, lun, *ucp, msg;
    802	unsigned long length, flags;
    803
    804	asr = read_aux_stat(regs);
    805	if (!(asr & ASR_INT) || (asr & ASR_BSY))
    806		return;
    807
    808	spin_lock_irqsave(&hostdata->lock, flags);
    809
    810#ifdef PROC_STATISTICS
    811	hostdata->int_cnt++;
    812#endif
    813
    814	cmd = (struct scsi_cmnd *) hostdata->connected;	/* assume we're connected */
    815	scsi_pointer = WD33C93_scsi_pointer(cmd);
    816	sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear the interrupt */
    817	phs = read_wd33c93(regs, WD_COMMAND_PHASE);
    818
    819	DB(DB_INTR, printk("{%02x:%02x-", asr, sr))
    820
    821/* After starting a DMA transfer, the next interrupt
    822 * is guaranteed to be in response to completion of
    823 * the transfer. Since the Amiga DMA hardware runs in
    824 * in an open-ended fashion, it needs to be told when
    825 * to stop; do that here if D_DMA_RUNNING is true.
    826 * Also, we have to update 'this_residual' and 'ptr'
    827 * based on the contents of the TRANSFER_COUNT register,
    828 * in case the device decided to do an intermediate
    829 * disconnect (a device may do this if it has to do a
    830 * seek, or just to be nice and let other devices have
    831 * some bus time during long transfers). After doing
    832 * whatever is needed, we go on and service the WD3393
    833 * interrupt normally.
    834 */
    835	    if (hostdata->dma == D_DMA_RUNNING) {
    836		DB(DB_TRANSFER,
    837		   printk("[%p/%d:", scsi_pointer->ptr, scsi_pointer->this_residual))
    838		    hostdata->dma_stop(cmd->device->host, cmd, 1);
    839		hostdata->dma = D_DMA_OFF;
    840		length = scsi_pointer->this_residual;
    841		scsi_pointer->this_residual = read_wd33c93_count(regs);
    842		scsi_pointer->ptr += length - scsi_pointer->this_residual;
    843		DB(DB_TRANSFER,
    844		   printk("%p/%d]", scsi_pointer->ptr, scsi_pointer->this_residual))
    845	}
    846
    847/* Respond to the specific WD3393 interrupt - there are quite a few! */
    848	switch (sr) {
    849	case CSR_TIMEOUT:
    850		DB(DB_INTR, printk("TIMEOUT"))
    851
    852		    if (hostdata->state == S_RUNNING_LEVEL2)
    853			hostdata->connected = NULL;
    854		else {
    855			cmd = (struct scsi_cmnd *) hostdata->selecting;	/* get a valid cmd */
    856			hostdata->selecting = NULL;
    857		}
    858
    859		cmd->result = DID_NO_CONNECT << 16;
    860		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
    861		hostdata->state = S_UNCONNECTED;
    862		scsi_done(cmd);
    863
    864		/* From esp.c:
    865		 * There is a window of time within the scsi_done() path
    866		 * of execution where interrupts are turned back on full
    867		 * blast and left that way.  During that time we could
    868		 * reconnect to a disconnected command, then we'd bomb
    869		 * out below.  We could also end up executing two commands
    870		 * at _once_.  ...just so you know why the restore_flags()
    871		 * is here...
    872		 */
    873
    874		spin_unlock_irqrestore(&hostdata->lock, flags);
    875
    876/* We are not connected to a target - check to see if there
    877 * are commands waiting to be executed.
    878 */
    879
    880		wd33c93_execute(instance);
    881		break;
    882
    883/* Note: this interrupt should not occur in a LEVEL2 command */
    884
    885	case CSR_SELECT:
    886		DB(DB_INTR, printk("SELECT"))
    887		    hostdata->connected = cmd =
    888		    (struct scsi_cmnd *) hostdata->selecting;
    889		hostdata->selecting = NULL;
    890
    891		/* construct an IDENTIFY message with correct disconnect bit */
    892
    893		hostdata->outgoing_msg[0] = IDENTIFY(0, cmd->device->lun);
    894		if (scsi_pointer->phase)
    895			hostdata->outgoing_msg[0] |= 0x40;
    896
    897		if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) {
    898
    899			hostdata->sync_stat[cmd->device->id] = SS_WAITING;
    900
    901/* Tack on a 2nd message to ask about synchronous transfers. If we've
    902 * been asked to do only asynchronous transfers on this device, we
    903 * request a fifo depth of 0, which is equivalent to async - should
    904 * solve the problems some people have had with GVP's Guru ROM.
    905 */
    906
    907			hostdata->outgoing_msg[1] = EXTENDED_MESSAGE;
    908			hostdata->outgoing_msg[2] = 3;
    909			hostdata->outgoing_msg[3] = EXTENDED_SDTR;
    910			if (hostdata->no_sync & (1 << cmd->device->id)) {
    911				calc_sync_msg(hostdata->default_sx_per, 0,
    912						0, hostdata->outgoing_msg + 4);
    913			} else {
    914				calc_sync_msg(optimum_sx_per(hostdata),
    915						OPTIMUM_SX_OFF,
    916						hostdata->fast,
    917						hostdata->outgoing_msg + 4);
    918			}
    919			hostdata->outgoing_len = 6;
    920#ifdef SYNC_DEBUG
    921			ucp = hostdata->outgoing_msg + 1;
    922			printk(" sending SDTR %02x03%02x%02x%02x ",
    923				ucp[0], ucp[2], ucp[3], ucp[4]);
    924#endif
    925		} else
    926			hostdata->outgoing_len = 1;
    927
    928		hostdata->state = S_CONNECTED;
    929		spin_unlock_irqrestore(&hostdata->lock, flags);
    930		break;
    931
    932	case CSR_XFER_DONE | PHS_DATA_IN:
    933	case CSR_UNEXP | PHS_DATA_IN:
    934	case CSR_SRV_REQ | PHS_DATA_IN:
    935		DB(DB_INTR,
    936		   printk("IN-%d.%d", scsi_pointer->this_residual,
    937			  scsi_pointer->buffers_residual))
    938		    transfer_bytes(regs, cmd, DATA_IN_DIR);
    939		if (hostdata->state != S_RUNNING_LEVEL2)
    940			hostdata->state = S_CONNECTED;
    941		spin_unlock_irqrestore(&hostdata->lock, flags);
    942		break;
    943
    944	case CSR_XFER_DONE | PHS_DATA_OUT:
    945	case CSR_UNEXP | PHS_DATA_OUT:
    946	case CSR_SRV_REQ | PHS_DATA_OUT:
    947		DB(DB_INTR,
    948		   printk("OUT-%d.%d", scsi_pointer->this_residual,
    949			  scsi_pointer->buffers_residual))
    950		    transfer_bytes(regs, cmd, DATA_OUT_DIR);
    951		if (hostdata->state != S_RUNNING_LEVEL2)
    952			hostdata->state = S_CONNECTED;
    953		spin_unlock_irqrestore(&hostdata->lock, flags);
    954		break;
    955
    956/* Note: this interrupt should not occur in a LEVEL2 command */
    957
    958	case CSR_XFER_DONE | PHS_COMMAND:
    959	case CSR_UNEXP | PHS_COMMAND:
    960	case CSR_SRV_REQ | PHS_COMMAND:
    961		DB(DB_INTR, printk("CMND-%02x", cmd->cmnd[0]))
    962		    transfer_pio(regs, cmd->cmnd, cmd->cmd_len, DATA_OUT_DIR,
    963				 hostdata);
    964		hostdata->state = S_CONNECTED;
    965		spin_unlock_irqrestore(&hostdata->lock, flags);
    966		break;
    967
    968	case CSR_XFER_DONE | PHS_STATUS:
    969	case CSR_UNEXP | PHS_STATUS:
    970	case CSR_SRV_REQ | PHS_STATUS:
    971		DB(DB_INTR, printk("STATUS="))
    972		scsi_pointer->Status = read_1_byte(regs);
    973		DB(DB_INTR, printk("%02x", scsi_pointer->Status))
    974		    if (hostdata->level2 >= L2_BASIC) {
    975			sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
    976			udelay(7);
    977			hostdata->state = S_RUNNING_LEVEL2;
    978			write_wd33c93(regs, WD_COMMAND_PHASE, 0x50);
    979			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
    980		} else {
    981			hostdata->state = S_CONNECTED;
    982		}
    983		spin_unlock_irqrestore(&hostdata->lock, flags);
    984		break;
    985
    986	case CSR_XFER_DONE | PHS_MESS_IN:
    987	case CSR_UNEXP | PHS_MESS_IN:
    988	case CSR_SRV_REQ | PHS_MESS_IN:
    989		DB(DB_INTR, printk("MSG_IN="))
    990
    991		msg = read_1_byte(regs);
    992		sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
    993		udelay(7);
    994
    995		hostdata->incoming_msg[hostdata->incoming_ptr] = msg;
    996		if (hostdata->incoming_msg[0] == EXTENDED_MESSAGE)
    997			msg = EXTENDED_MESSAGE;
    998		else
    999			hostdata->incoming_ptr = 0;
   1000
   1001		scsi_pointer->Message = msg;
   1002		switch (msg) {
   1003
   1004		case COMMAND_COMPLETE:
   1005			DB(DB_INTR, printk("CCMP"))
   1006			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1007			hostdata->state = S_PRE_CMP_DISC;
   1008			break;
   1009
   1010		case SAVE_POINTERS:
   1011			DB(DB_INTR, printk("SDP"))
   1012			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1013			hostdata->state = S_CONNECTED;
   1014			break;
   1015
   1016		case RESTORE_POINTERS:
   1017			DB(DB_INTR, printk("RDP"))
   1018			    if (hostdata->level2 >= L2_BASIC) {
   1019				write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
   1020				write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
   1021				hostdata->state = S_RUNNING_LEVEL2;
   1022			} else {
   1023				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1024				hostdata->state = S_CONNECTED;
   1025			}
   1026			break;
   1027
   1028		case DISCONNECT:
   1029			DB(DB_INTR, printk("DIS"))
   1030			    cmd->device->disconnect = 1;
   1031			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1032			hostdata->state = S_PRE_TMP_DISC;
   1033			break;
   1034
   1035		case MESSAGE_REJECT:
   1036			DB(DB_INTR, printk("REJ"))
   1037#ifdef SYNC_DEBUG
   1038			    printk("-REJ-");
   1039#endif
   1040			if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) {
   1041				hostdata->sync_stat[cmd->device->id] = SS_SET;
   1042				/* we want default_sx_per, not DEFAULT_SX_PER */
   1043				hostdata->sync_xfer[cmd->device->id] =
   1044					calc_sync_xfer(hostdata->default_sx_per
   1045						/ 4, 0, 0, hostdata->sx_table);
   1046			}
   1047			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1048			hostdata->state = S_CONNECTED;
   1049			break;
   1050
   1051		case EXTENDED_MESSAGE:
   1052			DB(DB_INTR, printk("EXT"))
   1053
   1054			    ucp = hostdata->incoming_msg;
   1055
   1056#ifdef SYNC_DEBUG
   1057			printk("%02x", ucp[hostdata->incoming_ptr]);
   1058#endif
   1059			/* Is this the last byte of the extended message? */
   1060
   1061			if ((hostdata->incoming_ptr >= 2) &&
   1062			    (hostdata->incoming_ptr == (ucp[1] + 1))) {
   1063
   1064				switch (ucp[2]) {	/* what's the EXTENDED code? */
   1065				case EXTENDED_SDTR:
   1066					/* default to default async period */
   1067					id = calc_sync_xfer(hostdata->
   1068							default_sx_per / 4, 0,
   1069							0, hostdata->sx_table);
   1070					if (hostdata->sync_stat[cmd->device->id] !=
   1071					    SS_WAITING) {
   1072
   1073/* A device has sent an unsolicited SDTR message; rather than go
   1074 * through the effort of decoding it and then figuring out what
   1075 * our reply should be, we're just gonna say that we have a
   1076 * synchronous fifo depth of 0. This will result in asynchronous
   1077 * transfers - not ideal but so much easier.
   1078 * Actually, this is OK because it assures us that if we don't
   1079 * specifically ask for sync transfers, we won't do any.
   1080 */
   1081
   1082						write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
   1083						hostdata->outgoing_msg[0] =
   1084						    EXTENDED_MESSAGE;
   1085						hostdata->outgoing_msg[1] = 3;
   1086						hostdata->outgoing_msg[2] =
   1087						    EXTENDED_SDTR;
   1088						calc_sync_msg(hostdata->
   1089							default_sx_per, 0,
   1090							0, hostdata->outgoing_msg + 3);
   1091						hostdata->outgoing_len = 5;
   1092					} else {
   1093						if (ucp[4]) /* well, sync transfer */
   1094							id = calc_sync_xfer(ucp[3], ucp[4],
   1095									hostdata->fast,
   1096									hostdata->sx_table);
   1097						else if (ucp[3]) /* very unlikely... */
   1098							id = calc_sync_xfer(ucp[3], ucp[4],
   1099									0, hostdata->sx_table);
   1100					}
   1101					hostdata->sync_xfer[cmd->device->id] = id;
   1102#ifdef SYNC_DEBUG
   1103					printk(" sync_xfer=%02x\n",
   1104					       hostdata->sync_xfer[cmd->device->id]);
   1105#endif
   1106					hostdata->sync_stat[cmd->device->id] =
   1107					    SS_SET;
   1108					write_wd33c93_cmd(regs,
   1109							  WD_CMD_NEGATE_ACK);
   1110					hostdata->state = S_CONNECTED;
   1111					break;
   1112				case EXTENDED_WDTR:
   1113					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
   1114					printk("sending WDTR ");
   1115					hostdata->outgoing_msg[0] =
   1116					    EXTENDED_MESSAGE;
   1117					hostdata->outgoing_msg[1] = 2;
   1118					hostdata->outgoing_msg[2] =
   1119					    EXTENDED_WDTR;
   1120					hostdata->outgoing_msg[3] = 0;	/* 8 bit transfer width */
   1121					hostdata->outgoing_len = 4;
   1122					write_wd33c93_cmd(regs,
   1123							  WD_CMD_NEGATE_ACK);
   1124					hostdata->state = S_CONNECTED;
   1125					break;
   1126				default:
   1127					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
   1128					printk
   1129					    ("Rejecting Unknown Extended Message(%02x). ",
   1130					     ucp[2]);
   1131					hostdata->outgoing_msg[0] =
   1132					    MESSAGE_REJECT;
   1133					hostdata->outgoing_len = 1;
   1134					write_wd33c93_cmd(regs,
   1135							  WD_CMD_NEGATE_ACK);
   1136					hostdata->state = S_CONNECTED;
   1137					break;
   1138				}
   1139				hostdata->incoming_ptr = 0;
   1140			}
   1141
   1142			/* We need to read more MESS_IN bytes for the extended message */
   1143
   1144			else {
   1145				hostdata->incoming_ptr++;
   1146				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1147				hostdata->state = S_CONNECTED;
   1148			}
   1149			break;
   1150
   1151		default:
   1152			printk("Rejecting Unknown Message(%02x) ", msg);
   1153			write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
   1154			hostdata->outgoing_msg[0] = MESSAGE_REJECT;
   1155			hostdata->outgoing_len = 1;
   1156			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1157			hostdata->state = S_CONNECTED;
   1158		}
   1159		spin_unlock_irqrestore(&hostdata->lock, flags);
   1160		break;
   1161
   1162/* Note: this interrupt will occur only after a LEVEL2 command */
   1163
   1164	case CSR_SEL_XFER_DONE:
   1165
   1166/* Make sure that reselection is enabled at this point - it may
   1167 * have been turned off for the command that just completed.
   1168 */
   1169
   1170		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
   1171		if (phs == 0x60) {
   1172			DB(DB_INTR, printk("SX-DONE"))
   1173			    scsi_pointer->Message = COMMAND_COMPLETE;
   1174			lun = read_wd33c93(regs, WD_TARGET_LUN);
   1175			DB(DB_INTR, printk(":%d.%d", scsi_pointer->Status, lun))
   1176			    hostdata->connected = NULL;
   1177			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
   1178			hostdata->state = S_UNCONNECTED;
   1179			if (scsi_pointer->Status == ILLEGAL_STATUS_BYTE)
   1180				scsi_pointer->Status = lun;
   1181			if (cmd->cmnd[0] == REQUEST_SENSE
   1182			    && scsi_pointer->Status != SAM_STAT_GOOD) {
   1183				set_host_byte(cmd, DID_ERROR);
   1184			} else {
   1185				set_host_byte(cmd, DID_OK);
   1186				scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
   1187				set_status_byte(cmd, scsi_pointer->Status);
   1188			}
   1189			scsi_done(cmd);
   1190
   1191/* We are no longer  connected to a target - check to see if
   1192 * there are commands waiting to be executed.
   1193 */
   1194			spin_unlock_irqrestore(&hostdata->lock, flags);
   1195			wd33c93_execute(instance);
   1196		} else {
   1197			printk
   1198			    ("%02x:%02x:%02x: Unknown SEL_XFER_DONE phase!!---",
   1199			     asr, sr, phs);
   1200			spin_unlock_irqrestore(&hostdata->lock, flags);
   1201		}
   1202		break;
   1203
   1204/* Note: this interrupt will occur only after a LEVEL2 command */
   1205
   1206	case CSR_SDP:
   1207		DB(DB_INTR, printk("SDP"))
   1208		    hostdata->state = S_RUNNING_LEVEL2;
   1209		write_wd33c93(regs, WD_COMMAND_PHASE, 0x41);
   1210		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
   1211		spin_unlock_irqrestore(&hostdata->lock, flags);
   1212		break;
   1213
   1214	case CSR_XFER_DONE | PHS_MESS_OUT:
   1215	case CSR_UNEXP | PHS_MESS_OUT:
   1216	case CSR_SRV_REQ | PHS_MESS_OUT:
   1217		DB(DB_INTR, printk("MSG_OUT="))
   1218
   1219/* To get here, we've probably requested MESSAGE_OUT and have
   1220 * already put the correct bytes in outgoing_msg[] and filled
   1221 * in outgoing_len. We simply send them out to the SCSI bus.
   1222 * Sometimes we get MESSAGE_OUT phase when we're not expecting
   1223 * it - like when our SDTR message is rejected by a target. Some
   1224 * targets send the REJECT before receiving all of the extended
   1225 * message, and then seem to go back to MESSAGE_OUT for a byte
   1226 * or two. Not sure why, or if I'm doing something wrong to
   1227 * cause this to happen. Regardless, it seems that sending
   1228 * NOP messages in these situations results in no harm and
   1229 * makes everyone happy.
   1230 */
   1231		    if (hostdata->outgoing_len == 0) {
   1232			hostdata->outgoing_len = 1;
   1233			hostdata->outgoing_msg[0] = NOP;
   1234		}
   1235		transfer_pio(regs, hostdata->outgoing_msg,
   1236			     hostdata->outgoing_len, DATA_OUT_DIR, hostdata);
   1237		DB(DB_INTR, printk("%02x", hostdata->outgoing_msg[0]))
   1238		    hostdata->outgoing_len = 0;
   1239		hostdata->state = S_CONNECTED;
   1240		spin_unlock_irqrestore(&hostdata->lock, flags);
   1241		break;
   1242
   1243	case CSR_UNEXP_DISC:
   1244
   1245/* I think I've seen this after a request-sense that was in response
   1246 * to an error condition, but not sure. We certainly need to do
   1247 * something when we get this interrupt - the question is 'what?'.
   1248 * Let's think positively, and assume some command has finished
   1249 * in a legal manner (like a command that provokes a request-sense),
   1250 * so we treat it as a normal command-complete-disconnect.
   1251 */
   1252
   1253/* Make sure that reselection is enabled at this point - it may
   1254 * have been turned off for the command that just completed.
   1255 */
   1256
   1257		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
   1258		if (cmd == NULL) {
   1259			printk(" - Already disconnected! ");
   1260			hostdata->state = S_UNCONNECTED;
   1261			spin_unlock_irqrestore(&hostdata->lock, flags);
   1262			return;
   1263		}
   1264		DB(DB_INTR, printk("UNEXP_DISC"))
   1265		    hostdata->connected = NULL;
   1266		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
   1267		hostdata->state = S_UNCONNECTED;
   1268		if (cmd->cmnd[0] == REQUEST_SENSE &&
   1269		    scsi_pointer->Status != SAM_STAT_GOOD) {
   1270			set_host_byte(cmd, DID_ERROR);
   1271		} else {
   1272			set_host_byte(cmd, DID_OK);
   1273			scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
   1274			set_status_byte(cmd, scsi_pointer->Status);
   1275		}
   1276		scsi_done(cmd);
   1277
   1278/* We are no longer connected to a target - check to see if
   1279 * there are commands waiting to be executed.
   1280 */
   1281		/* look above for comments on scsi_done() */
   1282		spin_unlock_irqrestore(&hostdata->lock, flags);
   1283		wd33c93_execute(instance);
   1284		break;
   1285
   1286	case CSR_DISC:
   1287
   1288/* Make sure that reselection is enabled at this point - it may
   1289 * have been turned off for the command that just completed.
   1290 */
   1291
   1292		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
   1293		DB(DB_INTR, printk("DISC"))
   1294		    if (cmd == NULL) {
   1295			printk(" - Already disconnected! ");
   1296			hostdata->state = S_UNCONNECTED;
   1297		}
   1298		switch (hostdata->state) {
   1299		case S_PRE_CMP_DISC:
   1300			hostdata->connected = NULL;
   1301			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
   1302			hostdata->state = S_UNCONNECTED;
   1303			DB(DB_INTR, printk(":%d", scsi_pointer->Status))
   1304			if (cmd->cmnd[0] == REQUEST_SENSE
   1305			    && scsi_pointer->Status != SAM_STAT_GOOD) {
   1306				set_host_byte(cmd, DID_ERROR);
   1307			} else {
   1308				set_host_byte(cmd, DID_OK);
   1309				scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
   1310				set_status_byte(cmd, scsi_pointer->Status);
   1311			}
   1312			scsi_done(cmd);
   1313			break;
   1314		case S_PRE_TMP_DISC:
   1315		case S_RUNNING_LEVEL2:
   1316			cmd->host_scribble = (uchar *) hostdata->disconnected_Q;
   1317			hostdata->disconnected_Q = cmd;
   1318			hostdata->connected = NULL;
   1319			hostdata->state = S_UNCONNECTED;
   1320
   1321#ifdef PROC_STATISTICS
   1322			hostdata->disc_done_cnt[cmd->device->id]++;
   1323#endif
   1324
   1325			break;
   1326		default:
   1327			printk("*** Unexpected DISCONNECT interrupt! ***");
   1328			hostdata->state = S_UNCONNECTED;
   1329		}
   1330
   1331/* We are no longer connected to a target - check to see if
   1332 * there are commands waiting to be executed.
   1333 */
   1334		spin_unlock_irqrestore(&hostdata->lock, flags);
   1335		wd33c93_execute(instance);
   1336		break;
   1337
   1338	case CSR_RESEL_AM:
   1339	case CSR_RESEL:
   1340		DB(DB_INTR, printk("RESEL%s", sr == CSR_RESEL_AM ? "_AM" : ""))
   1341
   1342		    /* Old chips (pre -A ???) don't have advanced features and will
   1343		     * generate CSR_RESEL.  In that case we have to extract the LUN the
   1344		     * hard way (see below).
   1345		     * First we have to make sure this reselection didn't
   1346		     * happen during Arbitration/Selection of some other device.
   1347		     * If yes, put losing command back on top of input_Q.
   1348		     */
   1349		    if (hostdata->level2 <= L2_NONE) {
   1350
   1351			if (hostdata->selecting) {
   1352				cmd = (struct scsi_cmnd *) hostdata->selecting;
   1353				hostdata->selecting = NULL;
   1354				hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
   1355				cmd->host_scribble =
   1356				    (uchar *) hostdata->input_Q;
   1357				hostdata->input_Q = cmd;
   1358			}
   1359		}
   1360
   1361		else {
   1362
   1363			if (cmd) {
   1364				if (phs == 0x00) {
   1365					hostdata->busy[cmd->device->id] &=
   1366						~(1 << (cmd->device->lun & 0xff));
   1367					cmd->host_scribble =
   1368					    (uchar *) hostdata->input_Q;
   1369					hostdata->input_Q = cmd;
   1370				} else {
   1371					printk
   1372					    ("---%02x:%02x:%02x-TROUBLE: Intrusive ReSelect!---",
   1373					     asr, sr, phs);
   1374					while (1)
   1375						printk("\r");
   1376				}
   1377			}
   1378
   1379		}
   1380
   1381		/* OK - find out which device reselected us. */
   1382
   1383		id = read_wd33c93(regs, WD_SOURCE_ID);
   1384		id &= SRCID_MASK;
   1385
   1386		/* and extract the lun from the ID message. (Note that we don't
   1387		 * bother to check for a valid message here - I guess this is
   1388		 * not the right way to go, but...)
   1389		 */
   1390
   1391		if (sr == CSR_RESEL_AM) {
   1392			lun = read_wd33c93(regs, WD_DATA);
   1393			if (hostdata->level2 < L2_RESELECT)
   1394				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
   1395			lun &= 7;
   1396		} else {
   1397			/* Old chip; wait for msgin phase to pick up the LUN. */
   1398			for (lun = 255; lun; lun--) {
   1399				if ((asr = read_aux_stat(regs)) & ASR_INT)
   1400					break;
   1401				udelay(10);
   1402			}
   1403			if (!(asr & ASR_INT)) {
   1404				printk
   1405				    ("wd33c93: Reselected without IDENTIFY\n");
   1406				lun = 0;
   1407			} else {
   1408				/* Verify this is a change to MSG_IN and read the message */
   1409				sr = read_wd33c93(regs, WD_SCSI_STATUS);
   1410				udelay(7);
   1411				if (sr == (CSR_ABORT | PHS_MESS_IN) ||
   1412				    sr == (CSR_UNEXP | PHS_MESS_IN) ||
   1413				    sr == (CSR_SRV_REQ | PHS_MESS_IN)) {
   1414					/* Got MSG_IN, grab target LUN */
   1415					lun = read_1_byte(regs);
   1416					/* Now we expect a 'paused with ACK asserted' int.. */
   1417					asr = read_aux_stat(regs);
   1418					if (!(asr & ASR_INT)) {
   1419						udelay(10);
   1420						asr = read_aux_stat(regs);
   1421						if (!(asr & ASR_INT))
   1422							printk
   1423							    ("wd33c93: No int after LUN on RESEL (%02x)\n",
   1424							     asr);
   1425					}
   1426					sr = read_wd33c93(regs, WD_SCSI_STATUS);
   1427					udelay(7);
   1428					if (sr != CSR_MSGIN)
   1429						printk
   1430						    ("wd33c93: Not paused with ACK on RESEL (%02x)\n",
   1431						     sr);
   1432					lun &= 7;
   1433					write_wd33c93_cmd(regs,
   1434							  WD_CMD_NEGATE_ACK);
   1435				} else {
   1436					printk
   1437					    ("wd33c93: Not MSG_IN on reselect (%02x)\n",
   1438					     sr);
   1439					lun = 0;
   1440				}
   1441			}
   1442		}
   1443
   1444		/* Now we look for the command that's reconnecting. */
   1445
   1446		cmd = (struct scsi_cmnd *) hostdata->disconnected_Q;
   1447		patch = NULL;
   1448		while (cmd) {
   1449			if (id == cmd->device->id && lun == (u8)cmd->device->lun)
   1450				break;
   1451			patch = cmd;
   1452			cmd = (struct scsi_cmnd *) cmd->host_scribble;
   1453		}
   1454
   1455		/* Hmm. Couldn't find a valid command.... What to do? */
   1456
   1457		if (!cmd) {
   1458			printk
   1459			    ("---TROUBLE: target %d.%d not in disconnect queue---",
   1460			     id, (u8)lun);
   1461			spin_unlock_irqrestore(&hostdata->lock, flags);
   1462			return;
   1463		}
   1464
   1465		/* Ok, found the command - now start it up again. */
   1466
   1467		if (patch)
   1468			patch->host_scribble = cmd->host_scribble;
   1469		else
   1470			hostdata->disconnected_Q =
   1471			    (struct scsi_cmnd *) cmd->host_scribble;
   1472		hostdata->connected = cmd;
   1473
   1474		/* We don't need to worry about 'initialize_SCp()' or 'hostdata->busy[]'
   1475		 * because these things are preserved over a disconnect.
   1476		 * But we DO need to fix the DPD bit so it's correct for this command.
   1477		 */
   1478
   1479		if (cmd->sc_data_direction == DMA_TO_DEVICE)
   1480			write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
   1481		else
   1482			write_wd33c93(regs, WD_DESTINATION_ID,
   1483				      cmd->device->id | DSTID_DPD);
   1484		if (hostdata->level2 >= L2_RESELECT) {
   1485			write_wd33c93_count(regs, 0);	/* we want a DATA_PHASE interrupt */
   1486			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
   1487			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
   1488			hostdata->state = S_RUNNING_LEVEL2;
   1489		} else
   1490			hostdata->state = S_CONNECTED;
   1491
   1492		    spin_unlock_irqrestore(&hostdata->lock, flags);
   1493		break;
   1494
   1495	default:
   1496		printk("--UNKNOWN INTERRUPT:%02x:%02x:%02x--", asr, sr, phs);
   1497		spin_unlock_irqrestore(&hostdata->lock, flags);
   1498	}
   1499
   1500	DB(DB_INTR, printk("} "))
   1501
   1502}
   1503
   1504static void
   1505reset_wd33c93(struct Scsi_Host *instance)
   1506{
   1507	struct WD33C93_hostdata *hostdata =
   1508	    (struct WD33C93_hostdata *) instance->hostdata;
   1509	const wd33c93_regs regs = hostdata->regs;
   1510	uchar sr;
   1511
   1512#ifdef CONFIG_SGI_IP22
   1513	{
   1514		int busycount = 0;
   1515		extern void sgiwd93_reset(unsigned long);
   1516		/* wait 'til the chip gets some time for us */
   1517		while ((read_aux_stat(regs) & ASR_BSY) && busycount++ < 100)
   1518			udelay (10);
   1519	/*
   1520 	 * there are scsi devices out there, which manage to lock up
   1521	 * the wd33c93 in a busy condition. In this state it won't
   1522	 * accept the reset command. The only way to solve this is to
   1523 	 * give the chip a hardware reset (if possible). The code below
   1524	 * does this for the SGI Indy, where this is possible
   1525	 */
   1526	/* still busy ? */
   1527	if (read_aux_stat(regs) & ASR_BSY)
   1528		sgiwd93_reset(instance->base); /* yeah, give it the hard one */
   1529	}
   1530#endif
   1531
   1532	write_wd33c93(regs, WD_OWN_ID, OWNID_EAF | OWNID_RAF |
   1533		      instance->this_id | hostdata->clock_freq);
   1534	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
   1535	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
   1536		      calc_sync_xfer(hostdata->default_sx_per / 4,
   1537				     DEFAULT_SX_OFF, 0, hostdata->sx_table));
   1538	write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET);
   1539
   1540
   1541#ifdef CONFIG_MVME147_SCSI
   1542	udelay(25);		/* The old wd33c93 on MVME147 needs this, at least */
   1543#endif
   1544
   1545	while (!(read_aux_stat(regs) & ASR_INT))
   1546		;
   1547	sr = read_wd33c93(regs, WD_SCSI_STATUS);
   1548
   1549	hostdata->microcode = read_wd33c93(regs, WD_CDB_1);
   1550	if (sr == 0x00)
   1551		hostdata->chip = C_WD33C93;
   1552	else if (sr == 0x01) {
   1553		write_wd33c93(regs, WD_QUEUE_TAG, 0xa5);	/* any random number */
   1554		sr = read_wd33c93(regs, WD_QUEUE_TAG);
   1555		if (sr == 0xa5) {
   1556			hostdata->chip = C_WD33C93B;
   1557			write_wd33c93(regs, WD_QUEUE_TAG, 0);
   1558		} else
   1559			hostdata->chip = C_WD33C93A;
   1560	} else
   1561		hostdata->chip = C_UNKNOWN_CHIP;
   1562
   1563	if (hostdata->chip != C_WD33C93B)	/* Fast SCSI unavailable */
   1564		hostdata->fast = 0;
   1565
   1566	write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE);
   1567	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
   1568}
   1569
   1570int
   1571wd33c93_host_reset(struct scsi_cmnd * SCpnt)
   1572{
   1573	struct Scsi_Host *instance;
   1574	struct WD33C93_hostdata *hostdata;
   1575	int i;
   1576
   1577	instance = SCpnt->device->host;
   1578	spin_lock_irq(instance->host_lock);
   1579	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
   1580
   1581	printk("scsi%d: reset. ", instance->host_no);
   1582	disable_irq(instance->irq);
   1583
   1584	hostdata->dma_stop(instance, NULL, 0);
   1585	for (i = 0; i < 8; i++) {
   1586		hostdata->busy[i] = 0;
   1587		hostdata->sync_xfer[i] =
   1588			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
   1589					0, hostdata->sx_table);
   1590		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
   1591	}
   1592	hostdata->input_Q = NULL;
   1593	hostdata->selecting = NULL;
   1594	hostdata->connected = NULL;
   1595	hostdata->disconnected_Q = NULL;
   1596	hostdata->state = S_UNCONNECTED;
   1597	hostdata->dma = D_DMA_OFF;
   1598	hostdata->incoming_ptr = 0;
   1599	hostdata->outgoing_len = 0;
   1600
   1601	reset_wd33c93(instance);
   1602	SCpnt->result = DID_RESET << 16;
   1603	enable_irq(instance->irq);
   1604	spin_unlock_irq(instance->host_lock);
   1605	return SUCCESS;
   1606}
   1607
   1608int
   1609wd33c93_abort(struct scsi_cmnd * cmd)
   1610{
   1611	struct Scsi_Host *instance;
   1612	struct WD33C93_hostdata *hostdata;
   1613	wd33c93_regs regs;
   1614	struct scsi_cmnd *tmp, *prev;
   1615
   1616	disable_irq(cmd->device->host->irq);
   1617
   1618	instance = cmd->device->host;
   1619	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
   1620	regs = hostdata->regs;
   1621
   1622/*
   1623 * Case 1 : If the command hasn't been issued yet, we simply remove it
   1624 *     from the input_Q.
   1625 */
   1626
   1627	tmp = (struct scsi_cmnd *) hostdata->input_Q;
   1628	prev = NULL;
   1629	while (tmp) {
   1630		if (tmp == cmd) {
   1631			if (prev)
   1632				prev->host_scribble = cmd->host_scribble;
   1633			else
   1634				hostdata->input_Q =
   1635				    (struct scsi_cmnd *) cmd->host_scribble;
   1636			cmd->host_scribble = NULL;
   1637			cmd->result = DID_ABORT << 16;
   1638			printk
   1639			    ("scsi%d: Abort - removing command from input_Q. ",
   1640			     instance->host_no);
   1641			enable_irq(cmd->device->host->irq);
   1642			scsi_done(cmd);
   1643			return SUCCESS;
   1644		}
   1645		prev = tmp;
   1646		tmp = (struct scsi_cmnd *) tmp->host_scribble;
   1647	}
   1648
   1649/*
   1650 * Case 2 : If the command is connected, we're going to fail the abort
   1651 *     and let the high level SCSI driver retry at a later time or
   1652 *     issue a reset.
   1653 *
   1654 *     Timeouts, and therefore aborted commands, will be highly unlikely
   1655 *     and handling them cleanly in this situation would make the common
   1656 *     case of noresets less efficient, and would pollute our code.  So,
   1657 *     we fail.
   1658 */
   1659
   1660	if (hostdata->connected == cmd) {
   1661		uchar sr, asr;
   1662		unsigned long timeout;
   1663
   1664		printk("scsi%d: Aborting connected command - ",
   1665		       instance->host_no);
   1666
   1667		printk("stopping DMA - ");
   1668		if (hostdata->dma == D_DMA_RUNNING) {
   1669			hostdata->dma_stop(instance, cmd, 0);
   1670			hostdata->dma = D_DMA_OFF;
   1671		}
   1672
   1673		printk("sending wd33c93 ABORT command - ");
   1674		write_wd33c93(regs, WD_CONTROL,
   1675			      CTRL_IDI | CTRL_EDI | CTRL_POLLED);
   1676		write_wd33c93_cmd(regs, WD_CMD_ABORT);
   1677
   1678/* Now we have to attempt to flush out the FIFO... */
   1679
   1680		printk("flushing fifo - ");
   1681		timeout = 1000000;
   1682		do {
   1683			asr = read_aux_stat(regs);
   1684			if (asr & ASR_DBR)
   1685				read_wd33c93(regs, WD_DATA);
   1686		} while (!(asr & ASR_INT) && timeout-- > 0);
   1687		sr = read_wd33c93(regs, WD_SCSI_STATUS);
   1688		printk
   1689		    ("asr=%02x, sr=%02x, %ld bytes un-transferred (timeout=%ld) - ",
   1690		     asr, sr, read_wd33c93_count(regs), timeout);
   1691
   1692		/*
   1693		 * Abort command processed.
   1694		 * Still connected.
   1695		 * We must disconnect.
   1696		 */
   1697
   1698		printk("sending wd33c93 DISCONNECT command - ");
   1699		write_wd33c93_cmd(regs, WD_CMD_DISCONNECT);
   1700
   1701		timeout = 1000000;
   1702		asr = read_aux_stat(regs);
   1703		while ((asr & ASR_CIP) && timeout-- > 0)
   1704			asr = read_aux_stat(regs);
   1705		sr = read_wd33c93(regs, WD_SCSI_STATUS);
   1706		printk("asr=%02x, sr=%02x.", asr, sr);
   1707
   1708		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
   1709		hostdata->connected = NULL;
   1710		hostdata->state = S_UNCONNECTED;
   1711		cmd->result = DID_ABORT << 16;
   1712
   1713/*      sti();*/
   1714		wd33c93_execute(instance);
   1715
   1716		enable_irq(cmd->device->host->irq);
   1717		scsi_done(cmd);
   1718		return SUCCESS;
   1719	}
   1720
   1721/*
   1722 * Case 3: If the command is currently disconnected from the bus,
   1723 * we're not going to expend much effort here: Let's just return
   1724 * an ABORT_SNOOZE and hope for the best...
   1725 */
   1726
   1727	tmp = (struct scsi_cmnd *) hostdata->disconnected_Q;
   1728	while (tmp) {
   1729		if (tmp == cmd) {
   1730			printk
   1731			    ("scsi%d: Abort - command found on disconnected_Q - ",
   1732			     instance->host_no);
   1733			printk("Abort SNOOZE. ");
   1734			enable_irq(cmd->device->host->irq);
   1735			return FAILED;
   1736		}
   1737		tmp = (struct scsi_cmnd *) tmp->host_scribble;
   1738	}
   1739
   1740/*
   1741 * Case 4 : If we reached this point, the command was not found in any of
   1742 *     the queues.
   1743 *
   1744 * We probably reached this point because of an unlikely race condition
   1745 * between the command completing successfully and the abortion code,
   1746 * so we won't panic, but we will notify the user in case something really
   1747 * broke.
   1748 */
   1749
   1750/*   sti();*/
   1751	wd33c93_execute(instance);
   1752
   1753	enable_irq(cmd->device->host->irq);
   1754	printk("scsi%d: warning : SCSI command probably completed successfully"
   1755	       "         before abortion. ", instance->host_no);
   1756	return FAILED;
   1757}
   1758
   1759#define MAX_WD33C93_HOSTS 4
   1760#define MAX_SETUP_ARGS ARRAY_SIZE(setup_args)
   1761#define SETUP_BUFFER_SIZE 200
   1762static char setup_buffer[SETUP_BUFFER_SIZE];
   1763static char setup_used[MAX_SETUP_ARGS];
   1764static int done_setup = 0;
   1765
   1766static int
   1767wd33c93_setup(char *str)
   1768{
   1769	int i;
   1770	char *p1, *p2;
   1771
   1772	/* The kernel does some processing of the command-line before calling
   1773	 * this function: If it begins with any decimal or hex number arguments,
   1774	 * ints[0] = how many numbers found and ints[1] through [n] are the values
   1775	 * themselves. str points to where the non-numeric arguments (if any)
   1776	 * start: We do our own parsing of those. We construct synthetic 'nosync'
   1777	 * keywords out of numeric args (to maintain compatibility with older
   1778	 * versions) and then add the rest of the arguments.
   1779	 */
   1780
   1781	p1 = setup_buffer;
   1782	*p1 = '\0';
   1783	if (str)
   1784		strncpy(p1, str, SETUP_BUFFER_SIZE - strlen(setup_buffer));
   1785	setup_buffer[SETUP_BUFFER_SIZE - 1] = '\0';
   1786	p1 = setup_buffer;
   1787	i = 0;
   1788	while (*p1 && (i < MAX_SETUP_ARGS)) {
   1789		p2 = strchr(p1, ',');
   1790		if (p2) {
   1791			*p2 = '\0';
   1792			if (p1 != p2)
   1793				setup_args[i] = p1;
   1794			p1 = p2 + 1;
   1795			i++;
   1796		} else {
   1797			setup_args[i] = p1;
   1798			break;
   1799		}
   1800	}
   1801	for (i = 0; i < MAX_SETUP_ARGS; i++)
   1802		setup_used[i] = 0;
   1803	done_setup = 1;
   1804
   1805	return 1;
   1806}
   1807__setup("wd33c93=", wd33c93_setup);
   1808
   1809/* check_setup_args() returns index if key found, 0 if not
   1810 */
   1811static int
   1812check_setup_args(char *key, int *flags, int *val, char *buf)
   1813{
   1814	int x;
   1815	char *cp;
   1816
   1817	for (x = 0; x < MAX_SETUP_ARGS; x++) {
   1818		if (setup_used[x])
   1819			continue;
   1820		if (!strncmp(setup_args[x], key, strlen(key)))
   1821			break;
   1822		if (!strncmp(setup_args[x], "next", strlen("next")))
   1823			return 0;
   1824	}
   1825	if (x == MAX_SETUP_ARGS)
   1826		return 0;
   1827	setup_used[x] = 1;
   1828	cp = setup_args[x] + strlen(key);
   1829	*val = -1;
   1830	if (*cp != ':')
   1831		return ++x;
   1832	cp++;
   1833	if ((*cp >= '0') && (*cp <= '9')) {
   1834		*val = simple_strtoul(cp, NULL, 0);
   1835	}
   1836	return ++x;
   1837}
   1838
   1839/*
   1840 * Calculate internal data-transfer-clock cycle from input-clock
   1841 * frequency (/MHz) and fill 'sx_table'.
   1842 *
   1843 * The original driver used to rely on a fixed sx_table, containing periods
   1844 * for (only) the lower limits of the respective input-clock-frequency ranges
   1845 * (8-10/12-15/16-20 MHz). Although it seems, that no problems occurred with
   1846 * this setting so far, it might be desirable to adjust the transfer periods
   1847 * closer to the really attached, possibly 25% higher, input-clock, since
   1848 * - the wd33c93 may really use a significant shorter period, than it has
   1849 *   negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz
   1850 *   instead).
   1851 * - the wd33c93 may ask the target for a lower transfer rate, than the target
   1852 *   is capable of (eg. negotiating for an assumed minimum of 252ns instead of
   1853 *   possible 200ns, which indeed shows up in tests as an approx. 10% lower
   1854 *   transfer rate).
   1855 */
   1856static inline unsigned int
   1857round_4(unsigned int x)
   1858{
   1859	switch (x & 3) {
   1860		case 1: --x;
   1861			break;
   1862		case 2: ++x;
   1863			fallthrough;
   1864		case 3: ++x;
   1865	}
   1866	return x;
   1867}
   1868
   1869static void
   1870calc_sx_table(unsigned int mhz, struct sx_period sx_table[9])
   1871{
   1872	unsigned int d, i;
   1873	if (mhz < 11)
   1874		d = 2;	/* divisor for  8-10 MHz input-clock */
   1875	else if (mhz < 16)
   1876		d = 3;	/* divisor for 12-15 MHz input-clock */
   1877	else
   1878		d = 4;	/* divisor for 16-20 MHz input-clock */
   1879
   1880	d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */
   1881
   1882	sx_table[0].period_ns = 1;
   1883	sx_table[0].reg_value = 0x20;
   1884	for (i = 1; i < 8; i++) {
   1885		sx_table[i].period_ns = round_4((i+1)*d / 100);
   1886		sx_table[i].reg_value = (i+1)*0x10;
   1887	}
   1888	sx_table[7].reg_value = 0;
   1889	sx_table[8].period_ns = 0;
   1890	sx_table[8].reg_value = 0;
   1891}
   1892
   1893/*
   1894 * check and, maybe, map an init- or "clock:"- argument.
   1895 */
   1896static uchar
   1897set_clk_freq(int freq, int *mhz)
   1898{
   1899	int x = freq;
   1900	if (WD33C93_FS_8_10 == freq)
   1901		freq = 8;
   1902	else if (WD33C93_FS_12_15 == freq)
   1903		freq = 12;
   1904	else if (WD33C93_FS_16_20 == freq)
   1905		freq = 16;
   1906	else if (freq > 7 && freq < 11)
   1907		x = WD33C93_FS_8_10;
   1908		else if (freq > 11 && freq < 16)
   1909		x = WD33C93_FS_12_15;
   1910		else if (freq > 15 && freq < 21)
   1911		x = WD33C93_FS_16_20;
   1912	else {
   1913			/* Hmm, wouldn't it be safer to assume highest freq here? */
   1914		x = WD33C93_FS_8_10;
   1915		freq = 8;
   1916	}
   1917	*mhz = freq;
   1918	return x;
   1919}
   1920
   1921/*
   1922 * to be used with the resync: fast: ... options
   1923 */
   1924static inline void set_resync ( struct WD33C93_hostdata *hd, int mask )
   1925{
   1926	int i;
   1927	for (i = 0; i < 8; i++)
   1928		if (mask & (1 << i))
   1929			hd->sync_stat[i] = SS_UNSET;
   1930}
   1931
   1932void
   1933wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs,
   1934	     dma_setup_t setup, dma_stop_t stop, int clock_freq)
   1935{
   1936	struct WD33C93_hostdata *hostdata;
   1937	int i;
   1938	int flags;
   1939	int val;
   1940	char buf[32];
   1941
   1942	if (!done_setup && setup_strings)
   1943		wd33c93_setup(setup_strings);
   1944
   1945	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
   1946
   1947	hostdata->regs = regs;
   1948	hostdata->clock_freq = set_clk_freq(clock_freq, &i);
   1949	calc_sx_table(i, hostdata->sx_table);
   1950	hostdata->dma_setup = setup;
   1951	hostdata->dma_stop = stop;
   1952	hostdata->dma_bounce_buffer = NULL;
   1953	hostdata->dma_bounce_len = 0;
   1954	for (i = 0; i < 8; i++) {
   1955		hostdata->busy[i] = 0;
   1956		hostdata->sync_xfer[i] =
   1957			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
   1958					0, hostdata->sx_table);
   1959		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
   1960#ifdef PROC_STATISTICS
   1961		hostdata->cmd_cnt[i] = 0;
   1962		hostdata->disc_allowed_cnt[i] = 0;
   1963		hostdata->disc_done_cnt[i] = 0;
   1964#endif
   1965	}
   1966	hostdata->input_Q = NULL;
   1967	hostdata->selecting = NULL;
   1968	hostdata->connected = NULL;
   1969	hostdata->disconnected_Q = NULL;
   1970	hostdata->state = S_UNCONNECTED;
   1971	hostdata->dma = D_DMA_OFF;
   1972	hostdata->level2 = L2_BASIC;
   1973	hostdata->disconnect = DIS_ADAPTIVE;
   1974	hostdata->args = DEBUG_DEFAULTS;
   1975	hostdata->incoming_ptr = 0;
   1976	hostdata->outgoing_len = 0;
   1977	hostdata->default_sx_per = DEFAULT_SX_PER;
   1978	hostdata->no_dma = 0;	/* default is DMA enabled */
   1979
   1980#ifdef PROC_INTERFACE
   1981	hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS |
   1982	    PR_CONNECTED | PR_INPUTQ | PR_DISCQ | PR_STOP;
   1983#ifdef PROC_STATISTICS
   1984	hostdata->dma_cnt = 0;
   1985	hostdata->pio_cnt = 0;
   1986	hostdata->int_cnt = 0;
   1987#endif
   1988#endif
   1989
   1990	if (check_setup_args("clock", &flags, &val, buf)) {
   1991		hostdata->clock_freq = set_clk_freq(val, &val);
   1992		calc_sx_table(val, hostdata->sx_table);
   1993	}
   1994
   1995	if (check_setup_args("nosync", &flags, &val, buf))
   1996		hostdata->no_sync = val;
   1997
   1998	if (check_setup_args("nodma", &flags, &val, buf))
   1999		hostdata->no_dma = (val == -1) ? 1 : val;
   2000
   2001	if (check_setup_args("period", &flags, &val, buf))
   2002		hostdata->default_sx_per =
   2003		    hostdata->sx_table[round_period((unsigned int) val,
   2004		                                    hostdata->sx_table)].period_ns;
   2005
   2006	if (check_setup_args("disconnect", &flags, &val, buf)) {
   2007		if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS))
   2008			hostdata->disconnect = val;
   2009		else
   2010			hostdata->disconnect = DIS_ADAPTIVE;
   2011	}
   2012
   2013	if (check_setup_args("level2", &flags, &val, buf))
   2014		hostdata->level2 = val;
   2015
   2016	if (check_setup_args("debug", &flags, &val, buf))
   2017		hostdata->args = val & DB_MASK;
   2018
   2019	if (check_setup_args("burst", &flags, &val, buf))
   2020		hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA;
   2021
   2022	if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */
   2023		&& check_setup_args("fast", &flags, &val, buf))
   2024		hostdata->fast = !!val;
   2025
   2026	if ((i = check_setup_args("next", &flags, &val, buf))) {
   2027		while (i)
   2028			setup_used[--i] = 1;
   2029	}
   2030#ifdef PROC_INTERFACE
   2031	if (check_setup_args("proc", &flags, &val, buf))
   2032		hostdata->proc = val;
   2033#endif
   2034
   2035	spin_lock_irq(&hostdata->lock);
   2036	reset_wd33c93(instance);
   2037	spin_unlock_irq(&hostdata->lock);
   2038
   2039	printk("wd33c93-%d: chip=%s/%d no_sync=0x%x no_dma=%d",
   2040	       instance->host_no,
   2041	       (hostdata->chip == C_WD33C93) ? "WD33c93" : (hostdata->chip ==
   2042							    C_WD33C93A) ?
   2043	       "WD33c93A" : (hostdata->chip ==
   2044			     C_WD33C93B) ? "WD33c93B" : "unknown",
   2045	       hostdata->microcode, hostdata->no_sync, hostdata->no_dma);
   2046#ifdef DEBUGGING_ON
   2047	printk(" debug_flags=0x%02x\n", hostdata->args);
   2048#else
   2049	printk(" debugging=OFF\n");
   2050#endif
   2051	printk("           setup_args=");
   2052	for (i = 0; i < MAX_SETUP_ARGS; i++)
   2053		printk("%s,", setup_args[i]);
   2054	printk("\n");
   2055	printk("           Version %s - %s\n", WD33C93_VERSION, WD33C93_DATE);
   2056}
   2057
   2058int wd33c93_write_info(struct Scsi_Host *instance, char *buf, int len)
   2059{
   2060#ifdef PROC_INTERFACE
   2061	char *bp;
   2062	struct WD33C93_hostdata *hd;
   2063	int x;
   2064
   2065	hd = (struct WD33C93_hostdata *) instance->hostdata;
   2066
   2067/* We accept the following
   2068 * keywords (same format as command-line, but arguments are not optional):
   2069 *    debug
   2070 *    disconnect
   2071 *    period
   2072 *    resync
   2073 *    proc
   2074 *    nodma
   2075 *    level2
   2076 *    burst
   2077 *    fast
   2078 *    nosync
   2079 */
   2080
   2081	buf[len] = '\0';
   2082	for (bp = buf; *bp; ) {
   2083		while (',' == *bp || ' ' == *bp)
   2084			++bp;
   2085	if (!strncmp(bp, "debug:", 6)) {
   2086			hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK;
   2087	} else if (!strncmp(bp, "disconnect:", 11)) {
   2088			x = simple_strtoul(bp+11, &bp, 0);
   2089		if (x < DIS_NEVER || x > DIS_ALWAYS)
   2090			x = DIS_ADAPTIVE;
   2091		hd->disconnect = x;
   2092	} else if (!strncmp(bp, "period:", 7)) {
   2093		x = simple_strtoul(bp+7, &bp, 0);
   2094		hd->default_sx_per =
   2095			hd->sx_table[round_period((unsigned int) x,
   2096						  hd->sx_table)].period_ns;
   2097	} else if (!strncmp(bp, "resync:", 7)) {
   2098			set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0));
   2099	} else if (!strncmp(bp, "proc:", 5)) {
   2100			hd->proc = simple_strtoul(bp+5, &bp, 0);
   2101	} else if (!strncmp(bp, "nodma:", 6)) {
   2102			hd->no_dma = simple_strtoul(bp+6, &bp, 0);
   2103	} else if (!strncmp(bp, "level2:", 7)) {
   2104			hd->level2 = simple_strtoul(bp+7, &bp, 0);
   2105		} else if (!strncmp(bp, "burst:", 6)) {
   2106			hd->dma_mode =
   2107				simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA;
   2108		} else if (!strncmp(bp, "fast:", 5)) {
   2109			x = !!simple_strtol(bp+5, &bp, 0);
   2110			if (x != hd->fast)
   2111				set_resync(hd, 0xff);
   2112			hd->fast = x;
   2113		} else if (!strncmp(bp, "nosync:", 7)) {
   2114			x = simple_strtoul(bp+7, &bp, 0);
   2115			set_resync(hd, x ^ hd->no_sync);
   2116			hd->no_sync = x;
   2117		} else {
   2118			break; /* unknown keyword,syntax-error,... */
   2119		}
   2120	}
   2121	return len;
   2122#else
   2123	return 0;
   2124#endif
   2125}
   2126
   2127int
   2128wd33c93_show_info(struct seq_file *m, struct Scsi_Host *instance)
   2129{
   2130#ifdef PROC_INTERFACE
   2131	struct WD33C93_hostdata *hd;
   2132	struct scsi_cmnd *cmd;
   2133	int x;
   2134
   2135	hd = (struct WD33C93_hostdata *) instance->hostdata;
   2136
   2137	spin_lock_irq(&hd->lock);
   2138	if (hd->proc & PR_VERSION)
   2139		seq_printf(m, "\nVersion %s - %s.",
   2140			WD33C93_VERSION, WD33C93_DATE);
   2141
   2142	if (hd->proc & PR_INFO) {
   2143		seq_printf(m, "\nclock_freq=%02x no_sync=%02x no_dma=%d"
   2144			" dma_mode=%02x fast=%d",
   2145			hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast);
   2146		seq_puts(m, "\nsync_xfer[] =       ");
   2147		for (x = 0; x < 7; x++)
   2148			seq_printf(m, "\t%02x", hd->sync_xfer[x]);
   2149		seq_puts(m, "\nsync_stat[] =       ");
   2150		for (x = 0; x < 7; x++)
   2151			seq_printf(m, "\t%02x", hd->sync_stat[x]);
   2152	}
   2153#ifdef PROC_STATISTICS
   2154	if (hd->proc & PR_STATISTICS) {
   2155		seq_puts(m, "\ncommands issued:    ");
   2156		for (x = 0; x < 7; x++)
   2157			seq_printf(m, "\t%ld", hd->cmd_cnt[x]);
   2158		seq_puts(m, "\ndisconnects allowed:");
   2159		for (x = 0; x < 7; x++)
   2160			seq_printf(m, "\t%ld", hd->disc_allowed_cnt[x]);
   2161		seq_puts(m, "\ndisconnects done:   ");
   2162		for (x = 0; x < 7; x++)
   2163			seq_printf(m, "\t%ld", hd->disc_done_cnt[x]);
   2164		seq_printf(m,
   2165			"\ninterrupts: %ld, DATA_PHASE ints: %ld DMA, %ld PIO",
   2166			hd->int_cnt, hd->dma_cnt, hd->pio_cnt);
   2167	}
   2168#endif
   2169	if (hd->proc & PR_CONNECTED) {
   2170		seq_puts(m, "\nconnected:     ");
   2171		if (hd->connected) {
   2172			cmd = (struct scsi_cmnd *) hd->connected;
   2173			seq_printf(m, " %d:%llu(%02x)",
   2174				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
   2175		}
   2176	}
   2177	if (hd->proc & PR_INPUTQ) {
   2178		seq_puts(m, "\ninput_Q:       ");
   2179		cmd = (struct scsi_cmnd *) hd->input_Q;
   2180		while (cmd) {
   2181			seq_printf(m, " %d:%llu(%02x)",
   2182				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
   2183			cmd = (struct scsi_cmnd *) cmd->host_scribble;
   2184		}
   2185	}
   2186	if (hd->proc & PR_DISCQ) {
   2187		seq_puts(m, "\ndisconnected_Q:");
   2188		cmd = (struct scsi_cmnd *) hd->disconnected_Q;
   2189		while (cmd) {
   2190			seq_printf(m, " %d:%llu(%02x)",
   2191				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
   2192			cmd = (struct scsi_cmnd *) cmd->host_scribble;
   2193		}
   2194	}
   2195	seq_putc(m, '\n');
   2196	spin_unlock_irq(&hd->lock);
   2197#endif				/* PROC_INTERFACE */
   2198	return 0;
   2199}
   2200
   2201EXPORT_SYMBOL(wd33c93_host_reset);
   2202EXPORT_SYMBOL(wd33c93_init);
   2203EXPORT_SYMBOL(wd33c93_abort);
   2204EXPORT_SYMBOL(wd33c93_queuecommand);
   2205EXPORT_SYMBOL(wd33c93_intr);
   2206EXPORT_SYMBOL(wd33c93_show_info);
   2207EXPORT_SYMBOL(wd33c93_write_info);