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v3.1
   1/*
   2 *  linux/drivers/acorn/scsi/acornscsi.c
   3 *
   4 *  Acorn SCSI 3 driver
   5 *  By R.M.King.
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * Abandoned using the Select and Transfer command since there were
  12 * some nasty races between our software and the target devices that
  13 * were not easy to solve, and the device errata had a lot of entries
  14 * for this command, some of them quite nasty...
  15 *
  16 * Changelog:
  17 *  26-Sep-1997	RMK	Re-jigged to use the queue module.
  18 *			Re-coded state machine to be based on driver
  19 *			state not scsi state.  Should be easier to debug.
  20 *			Added acornscsi_release to clean up properly.
  21 *			Updated proc/scsi reporting.
  22 *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
  23 *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
  24 *			reconnect race condition causing a warning message.
  25 *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
  26 *  15-Oct-1997	RMK	Improved handling of commands.
  27 *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
  28 *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
  29 *			transitions added to allow dodgy devices to work.
  30 */
  31#define DEBUG_NO_WRITE	1
  32#define DEBUG_QUEUES	2
  33#define DEBUG_DMA	4
  34#define DEBUG_ABORT	8
  35#define DEBUG_DISCON	16
  36#define DEBUG_CONNECT	32
  37#define DEBUG_PHASES	64
  38#define DEBUG_WRITE	128
  39#define DEBUG_LINK	256
  40#define DEBUG_MESSAGES	512
  41#define DEBUG_RESET	1024
  42#define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
  43			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
  44			 DEBUG_DMA|DEBUG_QUEUES)
  45
  46/* DRIVER CONFIGURATION
  47 *
  48 * SCSI-II Tagged queue support.
  49 *
  50 * I don't have any SCSI devices that support it, so it is totally untested
  51 * (except to make sure that it doesn't interfere with any non-tagging
  52 * devices).  It is not fully implemented either - what happens when a
  53 * tagging device reconnects???
  54 *
  55 * You can tell if you have a device that supports tagged queueing my
  56 * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
  57 * as '2 TAG'.
  58 *
  59 * Also note that CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE is normally set in the config
  60 * scripts, but disabled here.  Once debugged, remove the #undef, otherwise to debug,
  61 * comment out the undef.
  62 */
  63#undef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
  64/*
  65 * SCSI-II Linked command support.
  66 *
  67 * The higher level code doesn't support linked commands yet, and so the option
  68 * is undef'd here.
  69 */
  70#undef CONFIG_SCSI_ACORNSCSI_LINK
  71/*
  72 * SCSI-II Synchronous transfer support.
  73 *
  74 * Tried and tested...
  75 *
  76 * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
  77 * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
  78 * DEFAULT_PERIOD - default REQ period.
  79 */
  80#define SDTR_SIZE	12
  81#define SDTR_PERIOD	125
  82#define DEFAULT_PERIOD	500
  83
  84/*
  85 * Debugging information
  86 *
  87 * DEBUG	  - bit mask from list above
  88 * DEBUG_TARGET   - is defined to the target number if you want to debug
  89 *		    a specific target. [only recon/write/dma].
  90 */
  91#define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
  92/* only allow writing to SCSI device 0 */
  93#define NO_WRITE 0xFE
  94/*#define DEBUG_TARGET 2*/
  95/*
  96 * Select timeout time (in 10ms units)
  97 *
  98 * This is the timeout used between the start of selection and the WD33C93
  99 * chip deciding that the device isn't responding.
 100 */
 101#define TIMEOUT_TIME 10
 102/*
 103 * Define this if you want to have verbose explanation of SCSI
 104 * status/messages.
 105 */
 106#undef CONFIG_ACORNSCSI_CONSTANTS
 107/*
 108 * Define this if you want to use the on board DMAC [don't remove this option]
 109 * If not set, then use PIO mode (not currently supported).
 110 */
 111#define USE_DMAC
 112
 113/*
 114 * ====================================================================================
 115 */
 116
 117#ifdef DEBUG_TARGET
 118#define DBG(cmd,xxx...) \
 119  if (cmd->device->id == DEBUG_TARGET) { \
 120    xxx; \
 121  }
 122#else
 123#define DBG(cmd,xxx...) xxx
 124#endif
 125
 126#include <linux/module.h>
 127#include <linux/kernel.h>
 128#include <linux/string.h>
 129#include <linux/signal.h>
 130#include <linux/errno.h>
 131#include <linux/proc_fs.h>
 132#include <linux/ioport.h>
 133#include <linux/blkdev.h>
 134#include <linux/delay.h>
 135#include <linux/interrupt.h>
 136#include <linux/init.h>
 137#include <linux/bitops.h>
 138#include <linux/stringify.h>
 139#include <linux/io.h>
 140
 141#include <asm/system.h>
 142#include <asm/ecard.h>
 143
 144#include "../scsi.h"
 145#include <scsi/scsi_dbg.h>
 146#include <scsi/scsi_host.h>
 147#include <scsi/scsi_transport_spi.h>
 148#include "acornscsi.h"
 149#include "msgqueue.h"
 150#include "scsi.h"
 151
 152#include <scsi/scsicam.h>
 153
 154#define VER_MAJOR 2
 155#define VER_MINOR 0
 156#define VER_PATCH 6
 157
 158#ifndef ABORT_TAG
 159#define ABORT_TAG 0xd
 160#else
 161#error "Yippee!  ABORT TAG is now defined!  Remove this error!"
 162#endif
 163
 164#ifdef CONFIG_SCSI_ACORNSCSI_LINK
 165#error SCSI2 LINKed commands not supported (yet)!
 166#endif
 167
 168#ifdef USE_DMAC
 169/*
 170 * DMAC setup parameters
 171 */ 
 172#define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
 173#define INIT_DEVCON1	(DEVCON1_BHLD)
 174#define DMAC_READ	(MODECON_READ)
 175#define DMAC_WRITE	(MODECON_WRITE)
 176#define INIT_SBICDMA	(CTRL_DMABURST)
 177
 178#define scsi_xferred	have_data_in
 179
 180/*
 181 * Size of on-board DMA buffer
 182 */
 183#define DMAC_BUFFER_SIZE	65536
 184#endif
 185
 186#define STATUS_BUFFER_TO_PRINT	24
 187
 188unsigned int sdtr_period = SDTR_PERIOD;
 189unsigned int sdtr_size   = SDTR_SIZE;
 190
 191static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
 192			   unsigned int result);
 193static int acornscsi_reconnect_finish(AS_Host *host);
 194static void acornscsi_dma_cleanup(AS_Host *host);
 195static void acornscsi_abortcmd(AS_Host *host, unsigned char tag);
 196
 197/* ====================================================================================
 198 * Miscellaneous
 199 */
 200
 201/* Offsets from MEMC base */
 202#define SBIC_REGIDX	0x2000
 203#define SBIC_REGVAL	0x2004
 204#define DMAC_OFFSET	0x3000
 205
 206/* Offsets from FAST IOC base */
 207#define INT_REG		0x2000
 208#define PAGE_REG	0x3000
 209
 210static inline void sbic_arm_write(AS_Host *host, unsigned int reg, unsigned int value)
 211{
 212    writeb(reg, host->base + SBIC_REGIDX);
 213    writeb(value, host->base + SBIC_REGVAL);
 214}
 215
 216static inline int sbic_arm_read(AS_Host *host, unsigned int reg)
 217{
 218    if(reg == SBIC_ASR)
 219	   return readl(host->base + SBIC_REGIDX) & 255;
 220    writeb(reg, host->base + SBIC_REGIDX);
 221    return readl(host->base + SBIC_REGVAL) & 255;
 222}
 223
 224#define sbic_arm_writenext(host, val)	writeb((val), (host)->base + SBIC_REGVAL)
 225#define sbic_arm_readnext(host) 	readb((host)->base + SBIC_REGVAL)
 226
 227#ifdef USE_DMAC
 228#define dmac_read(host,reg) \
 229	readb((host)->base + DMAC_OFFSET + ((reg) << 2))
 230
 231#define dmac_write(host,reg,value) \
 232	({ writeb((value), (host)->base + DMAC_OFFSET + ((reg) << 2)); })
 233
 234#define dmac_clearintr(host) 	writeb(0, (host)->fast + INT_REG)
 235
 236static inline unsigned int dmac_address(AS_Host *host)
 237{
 238    return dmac_read(host, DMAC_TXADRHI) << 16 |
 239	   dmac_read(host, DMAC_TXADRMD) << 8 |
 240	   dmac_read(host, DMAC_TXADRLO);
 241}
 242
 243static
 244void acornscsi_dumpdma(AS_Host *host, char *where)
 245{
 246	unsigned int mode, addr, len;
 247
 248	mode = dmac_read(host, DMAC_MODECON);
 249	addr = dmac_address(host);
 250	len  = dmac_read(host, DMAC_TXCNTHI) << 8 |
 251	       dmac_read(host, DMAC_TXCNTLO);
 252
 253	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
 254		host->host->host_no, where,
 255		mode, addr, (len + 1) & 0xffff,
 256		dmac_read(host, DMAC_MASKREG));
 257
 258	printk("DMA @%06x, ", host->dma.start_addr);
 259	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
 260		host->scsi.SCp.this_residual);
 261	printk("DT @+%04x ST @+%04x", host->dma.transferred,
 262		host->scsi.SCp.scsi_xferred);
 263	printk("\n");
 264}
 265#endif
 266
 267static
 268unsigned long acornscsi_sbic_xfcount(AS_Host *host)
 269{
 270    unsigned long length;
 271
 272    length = sbic_arm_read(host, SBIC_TRANSCNTH) << 16;
 273    length |= sbic_arm_readnext(host) << 8;
 274    length |= sbic_arm_readnext(host);
 275
 276    return length;
 277}
 278
 279static int
 280acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
 281{
 282	int asr;
 283
 284	do {
 285		asr = sbic_arm_read(host, SBIC_ASR);
 286
 287		if ((asr & stat_mask) == stat)
 288			return 0;
 289
 290		udelay(1);
 291	} while (--timeout);
 292
 293	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);
 294
 295	return -1;
 296}
 297
 298static
 299int acornscsi_sbic_issuecmd(AS_Host *host, int command)
 300{
 301    if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
 302	return -1;
 303
 304    sbic_arm_write(host, SBIC_CMND, command);
 305
 306    return 0;
 307}
 308
 309static void
 310acornscsi_csdelay(unsigned int cs)
 311{
 312    unsigned long target_jiffies, flags;
 313
 314    target_jiffies = jiffies + 1 + cs * HZ / 100;
 315
 316    local_save_flags(flags);
 317    local_irq_enable();
 318
 319    while (time_before(jiffies, target_jiffies)) barrier();
 320
 321    local_irq_restore(flags);
 322}
 323
 324static
 325void acornscsi_resetcard(AS_Host *host)
 326{
 327    unsigned int i, timeout;
 328
 329    /* assert reset line */
 330    host->card.page_reg = 0x80;
 331    writeb(host->card.page_reg, host->fast + PAGE_REG);
 332
 333    /* wait 3 cs.  SCSI standard says 25ms. */
 334    acornscsi_csdelay(3);
 335
 336    host->card.page_reg = 0;
 337    writeb(host->card.page_reg, host->fast + PAGE_REG);
 338
 339    /*
 340     * Should get a reset from the card
 341     */
 342    timeout = 1000;
 343    do {
 344	if (readb(host->fast + INT_REG) & 8)
 345	    break;
 346	udelay(1);
 347    } while (--timeout);
 348
 349    if (timeout == 0)
 350	printk("scsi%d: timeout while resetting card\n",
 351		host->host->host_no);
 352
 353    sbic_arm_read(host, SBIC_ASR);
 354    sbic_arm_read(host, SBIC_SSR);
 355
 356    /* setup sbic - WD33C93A */
 357    sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
 358    sbic_arm_write(host, SBIC_CMND, CMND_RESET);
 359
 360    /*
 361     * Command should cause a reset interrupt
 362     */
 363    timeout = 1000;
 364    do {
 365	if (readb(host->fast + INT_REG) & 8)
 366	    break;
 367	udelay(1);
 368    } while (--timeout);
 369
 370    if (timeout == 0)
 371	printk("scsi%d: timeout while resetting card\n",
 372		host->host->host_no);
 373
 374    sbic_arm_read(host, SBIC_ASR);
 375    if (sbic_arm_read(host, SBIC_SSR) != 0x01)
 376	printk(KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
 377		host->host->host_no);
 378
 379    sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
 380    sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
 381    sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
 382    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
 383
 384    host->card.page_reg = 0x40;
 385    writeb(host->card.page_reg, host->fast + PAGE_REG);
 386
 387    /* setup dmac - uPC71071 */
 388    dmac_write(host, DMAC_INIT, 0);
 389#ifdef USE_DMAC
 390    dmac_write(host, DMAC_INIT, INIT_8BIT);
 391    dmac_write(host, DMAC_CHANNEL, CHANNEL_0);
 392    dmac_write(host, DMAC_DEVCON0, INIT_DEVCON0);
 393    dmac_write(host, DMAC_DEVCON1, INIT_DEVCON1);
 394#endif
 395
 396    host->SCpnt = NULL;
 397    host->scsi.phase = PHASE_IDLE;
 398    host->scsi.disconnectable = 0;
 399
 400    memset(host->busyluns, 0, sizeof(host->busyluns));
 401
 402    for (i = 0; i < 8; i++) {
 403	host->device[i].sync_state = SYNC_NEGOCIATE;
 404	host->device[i].disconnect_ok = 1;
 405    }
 406
 407    /* wait 25 cs.  SCSI standard says 250ms. */
 408    acornscsi_csdelay(25);
 409}
 410
 411/*=============================================================================================
 412 * Utility routines (eg. debug)
 413 */
 414#ifdef CONFIG_ACORNSCSI_CONSTANTS
 415static char *acornscsi_interrupttype[] = {
 416  "rst",  "suc",  "p/a",  "3",
 417  "term", "5",	  "6",	  "7",
 418  "serv", "9",	  "a",	  "b",
 419  "c",	  "d",	  "e",	  "f"
 420};
 421
 422static signed char acornscsi_map[] = {
 423  0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 424 -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 425 12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 426 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 427 15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
 428 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 429 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 430 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 431 21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 432 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 433 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 434 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 435 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 436 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 437 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 438 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
 439};      
 440
 441static char *acornscsi_interruptcode[] = {
 442    /* 0 */
 443    "reset - normal mode",	/* 00 */
 444    "reset - advanced mode",	/* 01 */
 445
 446    /* 2 */
 447    "sel",			/* 11 */
 448    "sel+xfer", 		/* 16 */
 449    "data-out", 		/* 18 */
 450    "data-in",			/* 19 */
 451    "cmd",			/* 1A */
 452    "stat",			/* 1B */
 453    "??-out",			/* 1C */
 454    "??-in",			/* 1D */
 455    "msg-out",			/* 1E */
 456    "msg-in",			/* 1F */
 457
 458    /* 12 */
 459    "/ACK asserted",		/* 20 */
 460    "save-data-ptr",		/* 21 */
 461    "{re}sel",			/* 22 */
 462
 463    /* 15 */
 464    "inv cmd",			/* 40 */
 465    "unexpected disconnect",	/* 41 */
 466    "sel timeout",		/* 42 */
 467    "P err",			/* 43 */
 468    "P err+ATN",		/* 44 */
 469    "bad status byte",		/* 47 */
 470
 471    /* 21 */
 472    "resel, no id",		/* 80 */
 473    "resel",			/* 81 */
 474    "discon",			/* 85 */
 475};
 476
 477static
 478void print_scsi_status(unsigned int ssr)
 479{
 480    if (acornscsi_map[ssr] != -1)
 481	printk("%s:%s",
 482		acornscsi_interrupttype[(ssr >> 4)],
 483		acornscsi_interruptcode[acornscsi_map[ssr]]);
 484    else
 485	printk("%X:%X", ssr >> 4, ssr & 0x0f);    
 486}    
 487#endif
 488
 489static
 490void print_sbic_status(int asr, int ssr, int cmdphase)
 491{
 492#ifdef CONFIG_ACORNSCSI_CONSTANTS
 493    printk("sbic: %c%c%c%c%c%c ",
 494	    asr & ASR_INT ? 'I' : 'i',
 495	    asr & ASR_LCI ? 'L' : 'l',
 496	    asr & ASR_BSY ? 'B' : 'b',
 497	    asr & ASR_CIP ? 'C' : 'c',
 498	    asr & ASR_PE  ? 'P' : 'p',
 499	    asr & ASR_DBR ? 'D' : 'd');
 500    printk("scsi: ");
 501    print_scsi_status(ssr);
 502    printk(" ph %02X\n", cmdphase);
 503#else
 504    printk("sbic: %02X scsi: %X:%X ph: %02X\n",
 505	    asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
 506#endif
 507}
 508
 509static void
 510acornscsi_dumplogline(AS_Host *host, int target, int line)
 511{
 512	unsigned long prev;
 513	signed int ptr;
 514
 515	ptr = host->status_ptr[target] - STATUS_BUFFER_TO_PRINT;
 516	if (ptr < 0)
 517		ptr += STATUS_BUFFER_SIZE;
 518
 519	printk("%c: %3s:", target == 8 ? 'H' : '0' + target,
 520		line == 0 ? "ph" : line == 1 ? "ssr" : "int");
 521
 522	prev = host->status[target][ptr].when;
 523
 524	for (; ptr != host->status_ptr[target]; ptr = (ptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
 525		unsigned long time_diff;
 526
 527		if (!host->status[target][ptr].when)
 528			continue;
 529
 530		switch (line) {
 531		case 0:
 532			printk("%c%02X", host->status[target][ptr].irq ? '-' : ' ',
 533					 host->status[target][ptr].ph);
 534			break;
 535
 536		case 1:
 537			printk(" %02X", host->status[target][ptr].ssr);
 538			break;
 539
 540		case 2:
 541			time_diff = host->status[target][ptr].when - prev;
 542			prev = host->status[target][ptr].when;
 543			if (time_diff == 0)
 544				printk("==^");
 545			else if (time_diff >= 100)
 546				printk("   ");
 547			else
 548				printk(" %02ld", time_diff);
 549			break;
 550		}
 551	}
 552
 553	printk("\n");
 554}
 555
 556static
 557void acornscsi_dumplog(AS_Host *host, int target)
 558{
 559    do {
 560	acornscsi_dumplogline(host, target, 0);
 561	acornscsi_dumplogline(host, target, 1);
 562	acornscsi_dumplogline(host, target, 2);
 563
 564	if (target == 8)
 565	    break;
 566
 567	target = 8;
 568    } while (1);
 569}
 570
 571static
 572char acornscsi_target(AS_Host *host)
 573{
 574	if (host->SCpnt)
 575		return '0' + host->SCpnt->device->id;
 576	return 'H';
 577}
 578
 579/*
 580 * Prototype: cmdtype_t acornscsi_cmdtype(int command)
 581 * Purpose  : differentiate READ from WRITE from other commands
 582 * Params   : command - command to interpret
 583 * Returns  : CMD_READ	- command reads data,
 584 *	      CMD_WRITE - command writes data,
 585 *	      CMD_MISC	- everything else
 586 */
 587static inline
 588cmdtype_t acornscsi_cmdtype(int command)
 589{
 590    switch (command) {
 591    case WRITE_6:  case WRITE_10:  case WRITE_12:
 592	return CMD_WRITE;
 593    case READ_6:   case READ_10:   case READ_12:
 594	return CMD_READ;
 595    default:
 596	return CMD_MISC;
 597    }
 598}
 599
 600/*
 601 * Prototype: int acornscsi_datadirection(int command)
 602 * Purpose  : differentiate between commands that have a DATA IN phase
 603 *	      and a DATA OUT phase
 604 * Params   : command - command to interpret
 605 * Returns  : DATADIR_OUT - data out phase expected
 606 *	      DATADIR_IN  - data in phase expected
 607 */
 608static
 609datadir_t acornscsi_datadirection(int command)
 610{
 611    switch (command) {
 612    case CHANGE_DEFINITION:	case COMPARE:		case COPY:
 613    case COPY_VERIFY:		case LOG_SELECT:	case MODE_SELECT:
 614    case MODE_SELECT_10:	case SEND_DIAGNOSTIC:	case WRITE_BUFFER:
 615    case FORMAT_UNIT:		case REASSIGN_BLOCKS:	case RESERVE:
 616    case SEARCH_EQUAL:		case SEARCH_HIGH:	case SEARCH_LOW:
 617    case WRITE_6:		case WRITE_10:		case WRITE_VERIFY:
 618    case UPDATE_BLOCK:		case WRITE_LONG:	case WRITE_SAME:
 619    case SEARCH_HIGH_12:	case SEARCH_EQUAL_12:	case SEARCH_LOW_12:
 620    case WRITE_12:		case WRITE_VERIFY_12:	case SET_WINDOW:
 621    case MEDIUM_SCAN:		case SEND_VOLUME_TAG:	case 0xea:
 622	return DATADIR_OUT;
 623    default:
 624	return DATADIR_IN;
 625    }
 626}
 627
 628/*
 629 * Purpose  : provide values for synchronous transfers with 33C93.
 630 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 631 *	Modified by Russell King for 8MHz WD33C93A
 632 */
 633static struct sync_xfer_tbl {
 634    unsigned int period_ns;
 635    unsigned char reg_value;
 636} sync_xfer_table[] = {
 637    {	1, 0x20 },    { 249, 0x20 },	{ 374, 0x30 },
 638    { 499, 0x40 },    { 624, 0x50 },	{ 749, 0x60 },
 639    { 874, 0x70 },    { 999, 0x00 },	{   0,	  0 }
 640};
 641
 642/*
 643 * Prototype: int acornscsi_getperiod(unsigned char syncxfer)
 644 * Purpose  : period for the synchronous transfer setting
 645 * Params   : syncxfer SYNCXFER register value
 646 * Returns  : period in ns.
 647 */
 648static
 649int acornscsi_getperiod(unsigned char syncxfer)
 650{
 651    int i;
 652
 653    syncxfer &= 0xf0;
 654    if (syncxfer == 0x10)
 655	syncxfer = 0;
 656
 657    for (i = 1; sync_xfer_table[i].period_ns; i++)
 658	if (syncxfer == sync_xfer_table[i].reg_value)
 659	    return sync_xfer_table[i].period_ns;
 660    return 0;
 661}
 662
 663/*
 664 * Prototype: int round_period(unsigned int period)
 665 * Purpose  : return index into above table for a required REQ period
 666 * Params   : period - time (ns) for REQ
 667 * Returns  : table index
 668 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 669 */
 670static inline
 671int round_period(unsigned int period)
 672{
 673    int i;
 674
 675    for (i = 1; sync_xfer_table[i].period_ns; i++) {
 676	if ((period <= sync_xfer_table[i].period_ns) &&
 677	    (period > sync_xfer_table[i - 1].period_ns))
 678	    return i;
 679    }
 680    return 7;
 681}
 682
 683/*
 684 * Prototype: unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
 685 * Purpose  : calculate value for 33c93s SYNC register
 686 * Params   : period - time (ns) for REQ
 687 *	      offset - offset in bytes between REQ/ACK
 688 * Returns  : value for SYNC register
 689 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 690 */
 691static
 692unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
 693{
 694    return sync_xfer_table[round_period(period)].reg_value |
 695		((offset < SDTR_SIZE) ? offset : SDTR_SIZE);
 696}
 697
 698/* ====================================================================================
 699 * Command functions
 700 */
 701/*
 702 * Function: acornscsi_kick(AS_Host *host)
 703 * Purpose : kick next command to interface
 704 * Params  : host - host to send command to
 705 * Returns : INTR_IDLE if idle, otherwise INTR_PROCESSING
 706 * Notes   : interrupts are always disabled!
 707 */
 708static
 709intr_ret_t acornscsi_kick(AS_Host *host)
 710{
 711    int from_queue = 0;
 712    struct scsi_cmnd *SCpnt;
 713
 714    /* first check to see if a command is waiting to be executed */
 715    SCpnt = host->origSCpnt;
 716    host->origSCpnt = NULL;
 717
 718    /* retrieve next command */
 719    if (!SCpnt) {
 720	SCpnt = queue_remove_exclude(&host->queues.issue, host->busyluns);
 721	if (!SCpnt)
 722	    return INTR_IDLE;
 723
 724	from_queue = 1;
 725    }
 726
 727    if (host->scsi.disconnectable && host->SCpnt) {
 728	queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
 729	host->scsi.disconnectable = 0;
 730#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
 731	DBG(host->SCpnt, printk("scsi%d.%c: moved command to disconnected queue\n",
 732		host->host->host_no, acornscsi_target(host)));
 733#endif
 734	host->SCpnt = NULL;
 735    }
 736
 737    /*
 738     * If we have an interrupt pending, then we may have been reselected.
 739     * In this case, we don't want to write to the registers
 740     */
 741    if (!(sbic_arm_read(host, SBIC_ASR) & (ASR_INT|ASR_BSY|ASR_CIP))) {
 742	sbic_arm_write(host, SBIC_DESTID, SCpnt->device->id);
 743	sbic_arm_write(host, SBIC_CMND, CMND_SELWITHATN);
 744    }
 745
 746    /*
 747     * claim host busy - all of these must happen atomically wrt
 748     * our interrupt routine.  Failure means command loss.
 749     */
 750    host->scsi.phase = PHASE_CONNECTING;
 751    host->SCpnt = SCpnt;
 752    host->scsi.SCp = SCpnt->SCp;
 753    host->dma.xfer_setup = 0;
 754    host->dma.xfer_required = 0;
 755    host->dma.xfer_done = 0;
 756
 757#if (DEBUG & (DEBUG_ABORT|DEBUG_CONNECT))
 758    DBG(SCpnt,printk("scsi%d.%c: starting cmd %02X\n",
 759	    host->host->host_no, '0' + SCpnt->device->id,
 760	    SCpnt->cmnd[0]));
 761#endif
 762
 763    if (from_queue) {
 764#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
 765	/*
 766	 * tagged queueing - allocate a new tag to this command
 767	 */
 768	if (SCpnt->device->simple_tags) {
 769	    SCpnt->device->current_tag += 1;
 770	    if (SCpnt->device->current_tag == 0)
 771		SCpnt->device->current_tag = 1;
 772	    SCpnt->tag = SCpnt->device->current_tag;
 773	} else
 774#endif
 775	    set_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
 776
 777	host->stats.removes += 1;
 778
 779	switch (acornscsi_cmdtype(SCpnt->cmnd[0])) {
 780	case CMD_WRITE:
 781	    host->stats.writes += 1;
 782	    break;
 783	case CMD_READ:
 784	    host->stats.reads += 1;
 785	    break;
 786	case CMD_MISC:
 787	    host->stats.miscs += 1;
 788	    break;
 789	}
 790    }
 791
 792    return INTR_PROCESSING;
 793}    
 794
 795/*
 796 * Function: void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp, unsigned int result)
 797 * Purpose : complete processing for command
 798 * Params  : host   - interface that completed
 799 *	     result - driver byte of result
 800 */
 801static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
 802			   unsigned int result)
 803{
 804	struct scsi_cmnd *SCpnt = *SCpntp;
 805
 806    /* clean up */
 807    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
 808
 809    host->stats.fins += 1;
 810
 811    if (SCpnt) {
 812	*SCpntp = NULL;
 813
 814	acornscsi_dma_cleanup(host);
 815
 816	SCpnt->result = result << 16 | host->scsi.SCp.Message << 8 | host->scsi.SCp.Status;
 817
 818	/*
 819	 * In theory, this should not happen.  In practice, it seems to.
 820	 * Only trigger an error if the device attempts to report all happy
 821	 * but with untransferred buffers...  If we don't do something, then
 822	 * data loss will occur.  Should we check SCpnt->underflow here?
 823	 * It doesn't appear to be set to something meaningful by the higher
 824	 * levels all the time.
 825	 */
 826	if (result == DID_OK) {
 827		int xfer_warn = 0;
 828
 829		if (SCpnt->underflow == 0) {
 830			if (host->scsi.SCp.ptr &&
 831			    acornscsi_cmdtype(SCpnt->cmnd[0]) != CMD_MISC)
 832				xfer_warn = 1;
 833		} else {
 834			if (host->scsi.SCp.scsi_xferred < SCpnt->underflow ||
 835			    host->scsi.SCp.scsi_xferred != host->dma.transferred)
 836				xfer_warn = 1;
 837		}
 838
 839		/* ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.6)
 840		 *  Targets which break data transfers into multiple
 841		 *  connections shall end each successful connection
 842		 *  (except possibly the last) with a SAVE DATA
 843		 *  POINTER - DISCONNECT message sequence.
 844		 *
 845		 * This makes it difficult to ensure that a transfer has
 846		 * completed.  If we reach the end of a transfer during
 847		 * the command, then we can only have finished the transfer.
 848		 * therefore, if we seem to have some data remaining, this
 849		 * is not a problem.
 850		 */
 851		if (host->dma.xfer_done)
 852			xfer_warn = 0;
 853
 854		if (xfer_warn) {
 855		    switch (status_byte(SCpnt->result)) {
 856		    case CHECK_CONDITION:
 857		    case COMMAND_TERMINATED:
 858		    case BUSY:
 859		    case QUEUE_FULL:
 860		    case RESERVATION_CONFLICT:
 861			break;
 862
 863		    default:
 864			printk(KERN_ERR "scsi%d.H: incomplete data transfer detected: result=%08X command=",
 865				host->host->host_no, SCpnt->result);
 866			__scsi_print_command(SCpnt->cmnd);
 867			acornscsi_dumpdma(host, "done");
 868		 	acornscsi_dumplog(host, SCpnt->device->id);
 869			SCpnt->result &= 0xffff;
 870			SCpnt->result |= DID_ERROR << 16;
 871		    }
 872		}
 873	}
 874
 875	if (!SCpnt->scsi_done)
 876	    panic("scsi%d.H: null scsi_done function in acornscsi_done", host->host->host_no);
 877
 878	clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
 879
 880	SCpnt->scsi_done(SCpnt);
 881    } else
 882	printk("scsi%d: null command in acornscsi_done", host->host->host_no);
 883
 884    host->scsi.phase = PHASE_IDLE;
 885}
 886
 887/* ====================================================================================
 888 * DMA routines
 889 */
 890/*
 891 * Purpose  : update SCSI Data Pointer
 892 * Notes    : this will only be one SG entry or less
 893 */
 894static
 895void acornscsi_data_updateptr(AS_Host *host, struct scsi_pointer *SCp, unsigned int length)
 896{
 897    SCp->ptr += length;
 898    SCp->this_residual -= length;
 899
 900    if (SCp->this_residual == 0 && next_SCp(SCp) == 0)
 901	host->dma.xfer_done = 1;
 902}
 903
 904/*
 905 * Prototype: void acornscsi_data_read(AS_Host *host, char *ptr,
 906 *				unsigned int start_addr, unsigned int length)
 907 * Purpose  : read data from DMA RAM
 908 * Params   : host - host to transfer from
 909 *	      ptr  - DRAM address
 910 *	      start_addr - host mem address
 911 *	      length - number of bytes to transfer
 912 * Notes    : this will only be one SG entry or less
 913 */
 914static
 915void acornscsi_data_read(AS_Host *host, char *ptr,
 916				 unsigned int start_addr, unsigned int length)
 917{
 918    extern void __acornscsi_in(void __iomem *, char *buf, int len);
 919    unsigned int page, offset, len = length;
 920
 921    page = (start_addr >> 12);
 922    offset = start_addr & ((1 << 12) - 1);
 923
 924    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 925
 926    while (len > 0) {
 927	unsigned int this_len;
 928
 929	if (len + offset > (1 << 12))
 930	    this_len = (1 << 12) - offset;
 931	else
 932	    this_len = len;
 933
 934	__acornscsi_in(host->base + (offset << 1), ptr, this_len);
 935
 936	offset += this_len;
 937	ptr += this_len;
 938	len -= this_len;
 939
 940	if (offset == (1 << 12)) {
 941	    offset = 0;
 942	    page ++;
 943	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 944	}
 945    }
 946    writeb(host->card.page_reg, host->fast + PAGE_REG);
 947}
 948
 949/*
 950 * Prototype: void acornscsi_data_write(AS_Host *host, char *ptr,
 951 *				unsigned int start_addr, unsigned int length)
 952 * Purpose  : write data to DMA RAM
 953 * Params   : host - host to transfer from
 954 *	      ptr  - DRAM address
 955 *	      start_addr - host mem address
 956 *	      length - number of bytes to transfer
 957 * Notes    : this will only be one SG entry or less
 958 */
 959static
 960void acornscsi_data_write(AS_Host *host, char *ptr,
 961				 unsigned int start_addr, unsigned int length)
 962{
 963    extern void __acornscsi_out(void __iomem *, char *buf, int len);
 964    unsigned int page, offset, len = length;
 965
 966    page = (start_addr >> 12);
 967    offset = start_addr & ((1 << 12) - 1);
 968
 969    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 970
 971    while (len > 0) {
 972	unsigned int this_len;
 973
 974	if (len + offset > (1 << 12))
 975	    this_len = (1 << 12) - offset;
 976	else
 977	    this_len = len;
 978
 979	__acornscsi_out(host->base + (offset << 1), ptr, this_len);
 980
 981	offset += this_len;
 982	ptr += this_len;
 983	len -= this_len;
 984
 985	if (offset == (1 << 12)) {
 986	    offset = 0;
 987	    page ++;
 988	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 989	}
 990    }
 991    writeb(host->card.page_reg, host->fast + PAGE_REG);
 992}
 993
 994/* =========================================================================================
 995 * On-board DMA routines
 996 */
 997#ifdef USE_DMAC
 998/*
 999 * Prototype: void acornscsi_dmastop(AS_Host *host)
1000 * Purpose  : stop all DMA
1001 * Params   : host - host on which to stop DMA
1002 * Notes    : This is called when leaving DATA IN/OUT phase,
1003 *	      or when interface is RESET
1004 */
1005static inline
1006void acornscsi_dma_stop(AS_Host *host)
1007{
1008    dmac_write(host, DMAC_MASKREG, MASK_ON);
1009    dmac_clearintr(host);
1010
1011#if (DEBUG & DEBUG_DMA)
1012    DBG(host->SCpnt, acornscsi_dumpdma(host, "stop"));
1013#endif
1014}
1015
1016/*
1017 * Function: void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1018 * Purpose : setup DMA controller for data transfer
1019 * Params  : host - host to setup
1020 *	     direction - data transfer direction
1021 * Notes   : This is called when entering DATA I/O phase, not
1022 *	     while we're in a DATA I/O phase
1023 */
1024static
1025void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1026{
1027    unsigned int address, length, mode;
1028
1029    host->dma.direction = direction;
1030
1031    dmac_write(host, DMAC_MASKREG, MASK_ON);
1032
1033    if (direction == DMA_OUT) {
1034#if (DEBUG & DEBUG_NO_WRITE)
1035	if (NO_WRITE & (1 << host->SCpnt->device->id)) {
1036	    printk(KERN_CRIT "scsi%d.%c: I can't handle DMA_OUT!\n",
1037		    host->host->host_no, acornscsi_target(host));
1038	    return;
1039	}
1040#endif
1041	mode = DMAC_WRITE;
1042    } else
1043	mode = DMAC_READ;
1044
1045    /*
1046     * Allocate some buffer space, limited to half the buffer size
1047     */
1048    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1049    if (length) {
1050	host->dma.start_addr = address = host->dma.free_addr;
1051	host->dma.free_addr = (host->dma.free_addr + length) &
1052				(DMAC_BUFFER_SIZE - 1);
1053
1054	/*
1055	 * Transfer data to DMA memory
1056	 */
1057	if (direction == DMA_OUT)
1058	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1059				length);
1060
1061	length -= 1;
1062	dmac_write(host, DMAC_TXCNTLO, length);
1063	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1064	dmac_write(host, DMAC_TXADRLO, address);
1065	dmac_write(host, DMAC_TXADRMD, address >> 8);
1066	dmac_write(host, DMAC_TXADRHI, 0);
1067	dmac_write(host, DMAC_MODECON, mode);
1068	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1069
1070#if (DEBUG & DEBUG_DMA)
1071	DBG(host->SCpnt, acornscsi_dumpdma(host, "strt"));
1072#endif
1073	host->dma.xfer_setup = 1;
1074    }
1075}
1076
1077/*
1078 * Function: void acornscsi_dma_cleanup(AS_Host *host)
1079 * Purpose : ensure that all DMA transfers are up-to-date & host->scsi.SCp is correct
1080 * Params  : host - host to finish
1081 * Notes   : This is called when a command is:
1082 *		terminating, RESTORE_POINTERS, SAVE_POINTERS, DISCONECT
1083 *	   : This must not return until all transfers are completed.
1084 */
1085static
1086void acornscsi_dma_cleanup(AS_Host *host)
1087{
1088    dmac_write(host, DMAC_MASKREG, MASK_ON);
1089    dmac_clearintr(host);
1090
1091    /*
1092     * Check for a pending transfer
1093     */
1094    if (host->dma.xfer_required) {
1095	host->dma.xfer_required = 0;
1096	if (host->dma.direction == DMA_IN)
1097	    acornscsi_data_read(host, host->dma.xfer_ptr,
1098				 host->dma.xfer_start, host->dma.xfer_length);
1099    }
1100
1101    /*
1102     * Has a transfer been setup?
1103     */
1104    if (host->dma.xfer_setup) {
1105	unsigned int transferred;
1106
1107	host->dma.xfer_setup = 0;
1108
1109#if (DEBUG & DEBUG_DMA)
1110	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupi"));
1111#endif
1112
1113	/*
1114	 * Calculate number of bytes transferred from DMA.
1115	 */
1116	transferred = dmac_address(host) - host->dma.start_addr;
1117	host->dma.transferred += transferred;
1118
1119	if (host->dma.direction == DMA_IN)
1120	    acornscsi_data_read(host, host->scsi.SCp.ptr,
1121				 host->dma.start_addr, transferred);
1122
1123	/*
1124	 * Update SCSI pointers
1125	 */
1126	acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1127#if (DEBUG & DEBUG_DMA)
1128	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupo"));
1129#endif
1130    }
1131}
1132
1133/*
1134 * Function: void acornscsi_dmacintr(AS_Host *host)
1135 * Purpose : handle interrupts from DMAC device
1136 * Params  : host - host to process
1137 * Notes   : If reading, we schedule the read to main memory &
1138 *	     allow the transfer to continue.
1139 *	   : If writing, we fill the onboard DMA memory from main
1140 *	     memory.
1141 *	   : Called whenever DMAC finished it's current transfer.
1142 */
1143static
1144void acornscsi_dma_intr(AS_Host *host)
1145{
1146    unsigned int address, length, transferred;
1147
1148#if (DEBUG & DEBUG_DMA)
1149    DBG(host->SCpnt, acornscsi_dumpdma(host, "inti"));
1150#endif
1151
1152    dmac_write(host, DMAC_MASKREG, MASK_ON);
1153    dmac_clearintr(host);
1154
1155    /*
1156     * Calculate amount transferred via DMA
1157     */
1158    transferred = dmac_address(host) - host->dma.start_addr;
1159    host->dma.transferred += transferred;
1160
1161    /*
1162     * Schedule DMA transfer off board
1163     */
1164    if (host->dma.direction == DMA_IN) {
1165	host->dma.xfer_start = host->dma.start_addr;
1166	host->dma.xfer_length = transferred;
1167	host->dma.xfer_ptr = host->scsi.SCp.ptr;
1168	host->dma.xfer_required = 1;
1169    }
1170
1171    acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1172
1173    /*
1174     * Allocate some buffer space, limited to half the on-board RAM size
1175     */
1176    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1177    if (length) {
1178	host->dma.start_addr = address = host->dma.free_addr;
1179	host->dma.free_addr = (host->dma.free_addr + length) &
1180				(DMAC_BUFFER_SIZE - 1);
1181
1182	/*
1183	 * Transfer data to DMA memory
1184	 */
1185	if (host->dma.direction == DMA_OUT)
1186	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1187				length);
1188
1189	length -= 1;
1190	dmac_write(host, DMAC_TXCNTLO, length);
1191	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1192	dmac_write(host, DMAC_TXADRLO, address);
1193	dmac_write(host, DMAC_TXADRMD, address >> 8);
1194	dmac_write(host, DMAC_TXADRHI, 0);
1195	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1196
1197#if (DEBUG & DEBUG_DMA)
1198	DBG(host->SCpnt, acornscsi_dumpdma(host, "into"));
1199#endif
1200    } else {
1201	host->dma.xfer_setup = 0;
1202#if 0
1203	/*
1204	 * If the interface still wants more, then this is an error.
1205	 * We give it another byte, but we also attempt to raise an
1206	 * attention condition.  We continue giving one byte until
1207	 * the device recognises the attention.
1208	 */
1209	if (dmac_read(host, DMAC_STATUS) & STATUS_RQ0) {
1210	    acornscsi_abortcmd(host, host->SCpnt->tag);
1211
1212	    dmac_write(host, DMAC_TXCNTLO, 0);
1213	    dmac_write(host, DMAC_TXCNTHI, 0);
1214	    dmac_write(host, DMAC_TXADRLO, 0);
1215	    dmac_write(host, DMAC_TXADRMD, 0);
1216	    dmac_write(host, DMAC_TXADRHI, 0);
1217	    dmac_write(host, DMAC_MASKREG, MASK_OFF);
1218	}
1219#endif
1220    }
1221}
1222
1223/*
1224 * Function: void acornscsi_dma_xfer(AS_Host *host)
1225 * Purpose : transfer data between AcornSCSI and memory
1226 * Params  : host - host to process
1227 */
1228static
1229void acornscsi_dma_xfer(AS_Host *host)
1230{
1231    host->dma.xfer_required = 0;
1232
1233    if (host->dma.direction == DMA_IN)
1234	acornscsi_data_read(host, host->dma.xfer_ptr,
1235				host->dma.xfer_start, host->dma.xfer_length);
1236}
1237
1238/*
1239 * Function: void acornscsi_dma_adjust(AS_Host *host)
1240 * Purpose : adjust DMA pointers & count for bytes transferred to
1241 *	     SBIC but not SCSI bus.
1242 * Params  : host - host to adjust DMA count for
1243 */
1244static
1245void acornscsi_dma_adjust(AS_Host *host)
1246{
1247    if (host->dma.xfer_setup) {
1248	signed long transferred;
1249#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1250	DBG(host->SCpnt, acornscsi_dumpdma(host, "adji"));
1251#endif
1252	/*
1253	 * Calculate correct DMA address - DMA is ahead of SCSI bus while
1254	 * writing.
1255	 *  host->scsi.SCp.scsi_xferred is the number of bytes
1256	 *  actually transferred to/from the SCSI bus.
1257	 *  host->dma.transferred is the number of bytes transferred
1258	 *  over DMA since host->dma.start_addr was last set.
1259	 *
1260	 * real_dma_addr = host->dma.start_addr + host->scsi.SCp.scsi_xferred
1261	 *		   - host->dma.transferred
1262	 */
1263	transferred = host->scsi.SCp.scsi_xferred - host->dma.transferred;
1264	if (transferred < 0)
1265	    printk("scsi%d.%c: Ack! DMA write correction %ld < 0!\n",
1266		    host->host->host_no, acornscsi_target(host), transferred);
1267	else if (transferred == 0)
1268	    host->dma.xfer_setup = 0;
1269	else {
1270	    transferred += host->dma.start_addr;
1271	    dmac_write(host, DMAC_TXADRLO, transferred);
1272	    dmac_write(host, DMAC_TXADRMD, transferred >> 8);
1273	    dmac_write(host, DMAC_TXADRHI, transferred >> 16);
1274#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1275	    DBG(host->SCpnt, acornscsi_dumpdma(host, "adjo"));
1276#endif
1277	}
1278    }
1279}
1280#endif
1281
1282/* =========================================================================================
1283 * Data I/O
1284 */
1285static int
1286acornscsi_write_pio(AS_Host *host, char *bytes, int *ptr, int len, unsigned int max_timeout)
1287{
1288	unsigned int asr, timeout = max_timeout;
1289	int my_ptr = *ptr;
1290
1291	while (my_ptr < len) {
1292		asr = sbic_arm_read(host, SBIC_ASR);
1293
1294		if (asr & ASR_DBR) {
1295			timeout = max_timeout;
1296
1297			sbic_arm_write(host, SBIC_DATA, bytes[my_ptr++]);
1298		} else if (asr & ASR_INT)
1299			break;
1300		else if (--timeout == 0)
1301			break;
1302		udelay(1);
1303	}
1304
1305	*ptr = my_ptr;
1306
1307	return (timeout == 0) ? -1 : 0;
1308}
1309
1310/*
1311 * Function: void acornscsi_sendcommand(AS_Host *host)
1312 * Purpose : send a command to a target
1313 * Params  : host - host which is connected to target
1314 */
1315static void
1316acornscsi_sendcommand(AS_Host *host)
1317{
1318	struct scsi_cmnd *SCpnt = host->SCpnt;
1319
1320    sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1321    sbic_arm_writenext(host, 0);
1322    sbic_arm_writenext(host, SCpnt->cmd_len - host->scsi.SCp.sent_command);
1323
1324    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1325
1326    if (acornscsi_write_pio(host, SCpnt->cmnd,
1327	(int *)&host->scsi.SCp.sent_command, SCpnt->cmd_len, 1000000))
1328	printk("scsi%d: timeout while sending command\n", host->host->host_no);
1329
1330    host->scsi.phase = PHASE_COMMAND;
1331}
1332
1333static
1334void acornscsi_sendmessage(AS_Host *host)
1335{
1336    unsigned int message_length = msgqueue_msglength(&host->scsi.msgs);
1337    unsigned int msgnr;
1338    struct message *msg;
1339
1340#if (DEBUG & DEBUG_MESSAGES)
1341    printk("scsi%d.%c: sending message ",
1342	    host->host->host_no, acornscsi_target(host));
1343#endif
1344
1345    switch (message_length) {
1346    case 0:
1347	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1348
1349	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 1");
1350
1351	sbic_arm_write(host, SBIC_DATA, NOP);
1352
1353	host->scsi.last_message = NOP;
1354#if (DEBUG & DEBUG_MESSAGES)
1355	printk("NOP");
1356#endif
1357	break;
1358
1359    case 1:
1360	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1361	msg = msgqueue_getmsg(&host->scsi.msgs, 0);
1362
1363	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 2");
1364
1365	sbic_arm_write(host, SBIC_DATA, msg->msg[0]);
1366
1367	host->scsi.last_message = msg->msg[0];
1368#if (DEBUG & DEBUG_MESSAGES)
1369	spi_print_msg(msg->msg);
1370#endif
1371	break;
1372
1373    default:
1374	/*
1375	 * ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.14)
1376	 * 'When a target sends this (MESSAGE_REJECT) message, it
1377	 *  shall change to MESSAGE IN phase and send this message
1378	 *  prior to requesting additional message bytes from the
1379	 *  initiator.  This provides an interlock so that the
1380	 *  initiator can determine which message byte is rejected.
1381	 */
1382	sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1383	sbic_arm_writenext(host, 0);
1384	sbic_arm_writenext(host, message_length);
1385	acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1386
1387	msgnr = 0;
1388	while ((msg = msgqueue_getmsg(&host->scsi.msgs, msgnr++)) != NULL) {
1389	    unsigned int i;
1390#if (DEBUG & DEBUG_MESSAGES)
1391	    spi_print_msg(msg);
1392#endif
1393	    i = 0;
1394	    if (acornscsi_write_pio(host, msg->msg, &i, msg->length, 1000000))
1395		printk("scsi%d: timeout while sending message\n", host->host->host_no);
1396
1397	    host->scsi.last_message = msg->msg[0];
1398	    if (msg->msg[0] == EXTENDED_MESSAGE)
1399		host->scsi.last_message |= msg->msg[2] << 8;
1400
1401	    if (i != msg->length)
1402		break;
1403	}
1404	break;
1405    }
1406#if (DEBUG & DEBUG_MESSAGES)
1407    printk("\n");
1408#endif
1409}
1410
1411/*
1412 * Function: void acornscsi_readstatusbyte(AS_Host *host)
1413 * Purpose : Read status byte from connected target
1414 * Params  : host - host connected to target
1415 */
1416static
1417void acornscsi_readstatusbyte(AS_Host *host)
1418{
1419    acornscsi_sbic_issuecmd(host, CMND_XFERINFO|CMND_SBT);
1420    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "reading status byte");
1421    host->scsi.SCp.Status = sbic_arm_read(host, SBIC_DATA);
1422}
1423
1424/*
1425 * Function: unsigned char acornscsi_readmessagebyte(AS_Host *host)
1426 * Purpose : Read one message byte from connected target
1427 * Params  : host - host connected to target
1428 */
1429static
1430unsigned char acornscsi_readmessagebyte(AS_Host *host)
1431{
1432    unsigned char message;
1433
1434    acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1435
1436    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "for message byte");
1437
1438    message = sbic_arm_read(host, SBIC_DATA);
1439
1440    /* wait for MSGIN-XFER-PAUSED */
1441    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after message byte");
1442
1443    sbic_arm_read(host, SBIC_SSR);
1444
1445    return message;
1446}
1447
1448/*
1449 * Function: void acornscsi_message(AS_Host *host)
1450 * Purpose : Read complete message from connected target & action message
1451 * Params  : host - host connected to target
1452 */
1453static
1454void acornscsi_message(AS_Host *host)
1455{
1456    unsigned char message[16];
1457    unsigned int msgidx = 0, msglen = 1;
1458
1459    do {
1460	message[msgidx] = acornscsi_readmessagebyte(host);
1461
1462	switch (msgidx) {
1463	case 0:
1464	    if (message[0] == EXTENDED_MESSAGE ||
1465		(message[0] >= 0x20 && message[0] <= 0x2f))
1466		msglen = 2;
1467	    break;
1468
1469	case 1:
1470	    if (message[0] == EXTENDED_MESSAGE)
1471		msglen += message[msgidx];
1472	    break;
1473	}
1474	msgidx += 1;
1475	if (msgidx < msglen) {
1476	    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1477
1478	    /* wait for next msg-in */
1479	    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after negate ack");
1480	    sbic_arm_read(host, SBIC_SSR);
1481	}
1482    } while (msgidx < msglen);
1483
1484#if (DEBUG & DEBUG_MESSAGES)
1485    printk("scsi%d.%c: message in: ",
1486	    host->host->host_no, acornscsi_target(host));
1487    spi_print_msg(message);
1488    printk("\n");
1489#endif
1490
1491    if (host->scsi.phase == PHASE_RECONNECTED) {
1492	/*
1493	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1494	 * 'Whenever a target reconnects to an initiator to continue
1495	 *  a tagged I/O process, the SIMPLE QUEUE TAG message shall
1496	 *  be sent immediately following the IDENTIFY message...'
1497	 */
1498	if (message[0] == SIMPLE_QUEUE_TAG)
1499	    host->scsi.reconnected.tag = message[1];
1500	if (acornscsi_reconnect_finish(host))
1501	    host->scsi.phase = PHASE_MSGIN;
1502    }
1503
1504    switch (message[0]) {
1505    case ABORT:
1506    case ABORT_TAG:
1507    case COMMAND_COMPLETE:
1508	if (host->scsi.phase != PHASE_STATUSIN) {
1509	    printk(KERN_ERR "scsi%d.%c: command complete following non-status in phase?\n",
1510		    host->host->host_no, acornscsi_target(host));
1511	    acornscsi_dumplog(host, host->SCpnt->device->id);
1512	}
1513	host->scsi.phase = PHASE_DONE;
1514	host->scsi.SCp.Message = message[0];
1515	break;
1516
1517    case SAVE_POINTERS:
1518	/*
1519	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.20)
1520	 * 'The SAVE DATA POINTER message is sent from a target to
1521	 *  direct the initiator to copy the active data pointer to
1522	 *  the saved data pointer for the current I/O process.
1523	 */
1524	acornscsi_dma_cleanup(host);
1525	host->SCpnt->SCp = host->scsi.SCp;
1526	host->SCpnt->SCp.sent_command = 0;
1527	host->scsi.phase = PHASE_MSGIN;
1528	break;
1529
1530    case RESTORE_POINTERS:
1531	/*
1532	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.19)
1533	 * 'The RESTORE POINTERS message is sent from a target to
1534	 *  direct the initiator to copy the most recently saved
1535	 *  command, data, and status pointers for the I/O process
1536	 *  to the corresponding active pointers.  The command and
1537	 *  status pointers shall be restored to the beginning of
1538	 *  the present command and status areas.'
1539	 */
1540	acornscsi_dma_cleanup(host);
1541	host->scsi.SCp = host->SCpnt->SCp;
1542	host->scsi.phase = PHASE_MSGIN;
1543	break;
1544
1545    case DISCONNECT:
1546	/*
1547	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 6.4.2)
1548	 * 'On those occasions when an error or exception condition occurs
1549	 *  and the target elects to repeat the information transfer, the
1550	 *  target may repeat the transfer either issuing a RESTORE POINTERS
1551	 *  message or by disconnecting without issuing a SAVE POINTERS
1552	 *  message.  When reconnection is completed, the most recent
1553	 *  saved pointer values are restored.'
1554	 */
1555	acornscsi_dma_cleanup(host);
1556	host->scsi.phase = PHASE_DISCONNECT;
1557	break;
1558
1559    case MESSAGE_REJECT:
1560#if 0 /* this isn't needed any more */
1561	/*
1562	 * If we were negociating sync transfer, we don't yet know if
1563	 * this REJECT is for the sync transfer or for the tagged queue/wide
1564	 * transfer.  Re-initiate sync transfer negotiation now, and if
1565	 * we got a REJECT in response to SDTR, then it'll be set to DONE.
1566	 */
1567	if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST)
1568	    host->device[host->SCpnt->device->id].sync_state = SYNC_NEGOCIATE;
1569#endif
1570
1571	/*
1572	 * If we have any messages waiting to go out, then assert ATN now
1573	 */
1574	if (msgqueue_msglength(&host->scsi.msgs))
1575	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1576
1577	switch (host->scsi.last_message) {
1578#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1579	case HEAD_OF_QUEUE_TAG:
1580	case ORDERED_QUEUE_TAG:
1581	case SIMPLE_QUEUE_TAG:
1582	    /*
1583	     * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1584	     *  If a target does not implement tagged queuing and a queue tag
1585	     *  message is received, it shall respond with a MESSAGE REJECT
1586	     *  message and accept the I/O process as if it were untagged.
1587	     */
1588	    printk(KERN_NOTICE "scsi%d.%c: disabling tagged queueing\n",
1589		    host->host->host_no, acornscsi_target(host));
1590	    host->SCpnt->device->simple_tags = 0;
1591	    set_bit(host->SCpnt->device->id * 8 + host->SCpnt->device->lun, host->busyluns);
1592	    break;
1593#endif
1594	case EXTENDED_MESSAGE | (EXTENDED_SDTR << 8):
1595	    /*
1596	     * Target can't handle synchronous transfers
1597	     */
1598	    printk(KERN_NOTICE "scsi%d.%c: Using asynchronous transfer\n",
1599		    host->host->host_no, acornscsi_target(host));
1600	    host->device[host->SCpnt->device->id].sync_xfer = SYNCHTRANSFER_2DBA;
1601	    host->device[host->SCpnt->device->id].sync_state = SYNC_ASYNCHRONOUS;
1602	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1603	    break;
1604
1605	default:
1606	    break;
1607	}
1608	break;
1609
1610    case QUEUE_FULL:
1611	/* TODO: target queue is full */
1612	break;
1613
1614    case SIMPLE_QUEUE_TAG:
1615	/* tag queue reconnect... message[1] = queue tag.  Print something to indicate something happened! */
1616	printk("scsi%d.%c: reconnect queue tag %02X\n",
1617		host->host->host_no, acornscsi_target(host),
1618		message[1]);
1619	break;
1620
1621    case EXTENDED_MESSAGE:
1622	switch (message[2]) {
1623#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1624	case EXTENDED_SDTR:
1625	    if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST) {
1626		/*
1627		 * We requested synchronous transfers.  This isn't quite right...
1628		 * We can only say if this succeeded if we proceed on to execute the
1629		 * command from this message.  If we get a MESSAGE PARITY ERROR,
1630		 * and the target retries fail, then we fallback to asynchronous mode
1631		 */
1632		host->device[host->SCpnt->device->id].sync_state = SYNC_COMPLETED;
1633		printk(KERN_NOTICE "scsi%d.%c: Using synchronous transfer, offset %d, %d ns\n",
1634			host->host->host_no, acornscsi_target(host),
1635			message[4], message[3] * 4);
1636		host->device[host->SCpnt->device->id].sync_xfer =
1637			calc_sync_xfer(message[3] * 4, message[4]);
1638	    } else {
1639		unsigned char period, length;
1640		/*
1641		 * Target requested synchronous transfers.  The agreement is only
1642		 * to be in operation AFTER the target leaves message out phase.
1643		 */
1644		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1645		period = max_t(unsigned int, message[3], sdtr_period / 4);
1646		length = min_t(unsigned int, message[4], sdtr_size);
1647		msgqueue_addmsg(&host->scsi.msgs, 5, EXTENDED_MESSAGE, 3,
1648				 EXTENDED_SDTR, period, length);
1649		host->device[host->SCpnt->device->id].sync_xfer =
1650			calc_sync_xfer(period * 4, length);
1651	    }
1652	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1653	    break;
1654#else
1655	    /* We do not accept synchronous transfers.  Respond with a
1656	     * MESSAGE_REJECT.
1657	     */
1658#endif
1659
1660	case EXTENDED_WDTR:
1661	    /* The WD33C93A is only 8-bit.  We respond with a MESSAGE_REJECT
1662	     * to a wide data transfer request.
1663	     */
1664	default:
1665	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1666	    msgqueue_flush(&host->scsi.msgs);
1667	    msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1668	    break;
1669	}
1670	break;
1671
1672#ifdef CONFIG_SCSI_ACORNSCSI_LINK
1673    case LINKED_CMD_COMPLETE:
1674    case LINKED_FLG_CMD_COMPLETE:
1675	/*
1676	 * We don't support linked commands yet
1677	 */
1678	if (0) {
1679#if (DEBUG & DEBUG_LINK)
1680	    printk("scsi%d.%c: lun %d tag %d linked command complete\n",
1681		    host->host->host_no, acornscsi_target(host), host->SCpnt->tag);
1682#endif
1683	    /*
1684	     * A linked command should only terminate with one of these messages
1685	     * if there are more linked commands available.
1686	     */
1687	    if (!host->SCpnt->next_link) {
1688		printk(KERN_WARNING "scsi%d.%c: lun %d tag %d linked command complete, but no next_link\n",
1689			instance->host_no, acornscsi_target(host), host->SCpnt->tag);
1690		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1691		msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1692	    } else {
1693		struct scsi_cmnd *SCpnt = host->SCpnt;
1694
1695		acornscsi_dma_cleanup(host);
1696
1697		host->SCpnt = host->SCpnt->next_link;
1698		host->SCpnt->tag = SCpnt->tag;
1699		SCpnt->result = DID_OK | host->scsi.SCp.Message << 8 | host->Scsi.SCp.Status;
1700		SCpnt->done(SCpnt);
1701
1702		/* initialise host->SCpnt->SCp */
1703	    }
1704	    break;
1705	}
1706#endif
1707
1708    default: /* reject message */
1709	printk(KERN_ERR "scsi%d.%c: unrecognised message %02X, rejecting\n",
1710		host->host->host_no, acornscsi_target(host),
1711		message[0]);
1712	acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1713	msgqueue_flush(&host->scsi.msgs);
1714	msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1715	host->scsi.phase = PHASE_MSGIN;
1716	break;
1717    }
1718    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1719}
1720
1721/*
1722 * Function: int acornscsi_buildmessages(AS_Host *host)
1723 * Purpose : build the connection messages for a host
1724 * Params  : host - host to add messages to
1725 */
1726static
1727void acornscsi_buildmessages(AS_Host *host)
1728{
1729#if 0
1730    /* does the device need resetting? */
1731    if (cmd_reset) {
1732	msgqueue_addmsg(&host->scsi.msgs, 1, BUS_DEVICE_RESET);
1733	return;
1734    }
1735#endif
1736
1737    msgqueue_addmsg(&host->scsi.msgs, 1,
1738		     IDENTIFY(host->device[host->SCpnt->device->id].disconnect_ok,
1739			     host->SCpnt->device->lun));
1740
1741#if 0
1742    /* does the device need the current command aborted */
1743    if (cmd_aborted) {
1744	acornscsi_abortcmd(host->SCpnt->tag);
1745	return;
1746    }
1747#endif
1748
1749#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1750    if (host->SCpnt->tag) {
1751	unsigned int tag_type;
1752
1753	if (host->SCpnt->cmnd[0] == REQUEST_SENSE ||
1754	    host->SCpnt->cmnd[0] == TEST_UNIT_READY ||
1755	    host->SCpnt->cmnd[0] == INQUIRY)
1756	    tag_type = HEAD_OF_QUEUE_TAG;
1757	else
1758	    tag_type = SIMPLE_QUEUE_TAG;
1759	msgqueue_addmsg(&host->scsi.msgs, 2, tag_type, host->SCpnt->tag);
1760    }
1761#endif
1762
1763#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1764    if (host->device[host->SCpnt->device->id].sync_state == SYNC_NEGOCIATE) {
1765	host->device[host->SCpnt->device->id].sync_state = SYNC_SENT_REQUEST;
1766	msgqueue_addmsg(&host->scsi.msgs, 5,
1767			 EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
1768			 sdtr_period / 4, sdtr_size);
1769    }
1770#endif
1771}
1772
1773/*
1774 * Function: int acornscsi_starttransfer(AS_Host *host)
1775 * Purpose : transfer data to/from connected target
1776 * Params  : host - host to which target is connected
1777 * Returns : 0 if failure
1778 */
1779static
1780int acornscsi_starttransfer(AS_Host *host)
1781{
1782    int residual;
1783
1784    if (!host->scsi.SCp.ptr /*&& host->scsi.SCp.this_residual*/) {
1785	printk(KERN_ERR "scsi%d.%c: null buffer passed to acornscsi_starttransfer\n",
1786		host->host->host_no, acornscsi_target(host));
1787	return 0;
1788    }
1789
1790    residual = scsi_bufflen(host->SCpnt) - host->scsi.SCp.scsi_xferred;
1791
1792    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1793    sbic_arm_writenext(host, residual >> 16);
1794    sbic_arm_writenext(host, residual >> 8);
1795    sbic_arm_writenext(host, residual);
1796    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1797    return 1;
1798}
1799
1800/* =========================================================================================
1801 * Connection & Disconnection
1802 */
1803/*
1804 * Function : acornscsi_reconnect(AS_Host *host)
1805 * Purpose  : reconnect a previously disconnected command
1806 * Params   : host - host specific data
1807 * Remarks  : SCSI spec says:
1808 *		'The set of active pointers is restored from the set
1809 *		 of saved pointers upon reconnection of the I/O process'
1810 */
1811static
1812int acornscsi_reconnect(AS_Host *host)
1813{
1814    unsigned int target, lun, ok = 0;
1815
1816    target = sbic_arm_read(host, SBIC_SOURCEID);
1817
1818    if (!(target & 8))
1819	printk(KERN_ERR "scsi%d: invalid source id after reselection "
1820		"- device fault?\n",
1821		host->host->host_no);
1822
1823    target &= 7;
1824
1825    if (host->SCpnt && !host->scsi.disconnectable) {
1826	printk(KERN_ERR "scsi%d.%d: reconnected while command in "
1827		"progress to target %d?\n",
1828		host->host->host_no, target, host->SCpnt->device->id);
1829	host->SCpnt = NULL;
1830    }
1831
1832    lun = sbic_arm_read(host, SBIC_DATA) & 7;
1833
1834    host->scsi.reconnected.target = target;
1835    host->scsi.reconnected.lun = lun;
1836    host->scsi.reconnected.tag = 0;
1837
1838    if (host->scsi.disconnectable && host->SCpnt &&
1839	host->SCpnt->device->id == target && host->SCpnt->device->lun == lun)
1840	ok = 1;
1841
1842    if (!ok && queue_probetgtlun(&host->queues.disconnected, target, lun))
1843	ok = 1;
1844
1845    ADD_STATUS(target, 0x81, host->scsi.phase, 0);
1846
1847    if (ok) {
1848	host->scsi.phase = PHASE_RECONNECTED;
1849    } else {
1850	/* this doesn't seem to work */
1851	printk(KERN_ERR "scsi%d.%c: reselected with no command "
1852		"to reconnect with\n",
1853		host->host->host_no, '0' + target);
1854	acornscsi_dumplog(host, target);
1855	acornscsi_abortcmd(host, 0);
1856	if (host->SCpnt) {
1857	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1858	    host->SCpnt = NULL;
1859	}
1860    }
1861    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1862    return !ok;
1863}
1864
1865/*
1866 * Function: int acornscsi_reconect_finish(AS_Host *host)
1867 * Purpose : finish reconnecting a command
1868 * Params  : host - host to complete
1869 * Returns : 0 if failed
1870 */
1871static
1872int acornscsi_reconnect_finish(AS_Host *host)
1873{
1874    if (host->scsi.disconnectable && host->SCpnt) {
1875	host->scsi.disconnectable = 0;
1876	if (host->SCpnt->device->id  == host->scsi.reconnected.target &&
1877	    host->SCpnt->device->lun == host->scsi.reconnected.lun &&
1878	    host->SCpnt->tag         == host->scsi.reconnected.tag) {
1879#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1880	    DBG(host->SCpnt, printk("scsi%d.%c: reconnected",
1881		    host->host->host_no, acornscsi_target(host)));
1882#endif
1883	} else {
1884	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1885#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1886	    DBG(host->SCpnt, printk("scsi%d.%c: had to move command "
1887		    "to disconnected queue\n",
1888		    host->host->host_no, acornscsi_target(host)));
1889#endif
1890	    host->SCpnt = NULL;
1891	}
1892    }
1893    if (!host->SCpnt) {
1894	host->SCpnt = queue_remove_tgtluntag(&host->queues.disconnected,
1895				host->scsi.reconnected.target,
1896				host->scsi.reconnected.lun,
1897				host->scsi.reconnected.tag);
1898#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1899	DBG(host->SCpnt, printk("scsi%d.%c: had to get command",
1900		host->host->host_no, acornscsi_target(host)));
1901#endif
1902    }
1903
1904    if (!host->SCpnt)
1905	acornscsi_abortcmd(host, host->scsi.reconnected.tag);
1906    else {
1907	/*
1908	 * Restore data pointer from SAVED pointers.
1909	 */
1910	host->scsi.SCp = host->SCpnt->SCp;
1911#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1912	printk(", data pointers: [%p, %X]",
1913		host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
1914#endif
1915    }
1916#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1917    printk("\n");
1918#endif
1919
1920    host->dma.transferred = host->scsi.SCp.scsi_xferred;
1921
1922    return host->SCpnt != NULL;
1923}
1924
1925/*
1926 * Function: void acornscsi_disconnect_unexpected(AS_Host *host)
1927 * Purpose : handle an unexpected disconnect
1928 * Params  : host - host on which disconnect occurred
1929 */
1930static
1931void acornscsi_disconnect_unexpected(AS_Host *host)
1932{
1933    printk(KERN_ERR "scsi%d.%c: unexpected disconnect\n",
1934	    host->host->host_no, acornscsi_target(host));
1935#if (DEBUG & DEBUG_ABORT)
1936    acornscsi_dumplog(host, 8);
1937#endif
1938
1939    acornscsi_done(host, &host->SCpnt, DID_ERROR);
1940}
1941
1942/*
1943 * Function: void acornscsi_abortcmd(AS_host *host, unsigned char tag)
1944 * Purpose : abort a currently executing command
1945 * Params  : host - host with connected command to abort
1946 *	     tag  - tag to abort
1947 */
1948static
1949void acornscsi_abortcmd(AS_Host *host, unsigned char tag)
1950{
1951    host->scsi.phase = PHASE_ABORTED;
1952    sbic_arm_write(host, SBIC_CMND, CMND_ASSERTATN);
1953
1954    msgqueue_flush(&host->scsi.msgs);
1955#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1956    if (tag)
1957	msgqueue_addmsg(&host->scsi.msgs, 2, ABORT_TAG, tag);
1958    else
1959#endif
1960	msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1961}
1962
1963/* ==========================================================================================
1964 * Interrupt routines.
1965 */
1966/*
1967 * Function: int acornscsi_sbicintr(AS_Host *host)
1968 * Purpose : handle interrupts from SCSI device
1969 * Params  : host - host to process
1970 * Returns : INTR_PROCESS if expecting another SBIC interrupt
1971 *	     INTR_IDLE if no interrupt
1972 *	     INTR_NEXT_COMMAND if we have finished processing the command
1973 */
1974static
1975intr_ret_t acornscsi_sbicintr(AS_Host *host, int in_irq)
1976{
1977    unsigned int asr, ssr;
1978
1979    asr = sbic_arm_read(host, SBIC_ASR);
1980    if (!(asr & ASR_INT))
1981	return INTR_IDLE;
1982
1983    ssr = sbic_arm_read(host, SBIC_SSR);
1984
1985#if (DEBUG & DEBUG_PHASES)
1986    print_sbic_status(asr, ssr, host->scsi.phase);
1987#endif
1988
1989    ADD_STATUS(8, ssr, host->scsi.phase, in_irq);
1990
1991    if (host->SCpnt && !host->scsi.disconnectable)
1992	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
1993
1994    switch (ssr) {
1995    case 0x00:				/* reset state - not advanced			*/
1996	printk(KERN_ERR "scsi%d: reset in standard mode but wanted advanced mode.\n",
1997		host->host->host_no);
1998	/* setup sbic - WD33C93A */
1999	sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
2000	sbic_arm_write(host, SBIC_CMND, CMND_RESET);
2001	return INTR_IDLE;
2002
2003    case 0x01:				/* reset state - advanced			*/
2004	sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
2005	sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
2006	sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
2007	sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
2008	msgqueue_flush(&host->scsi.msgs);
2009	return INTR_IDLE;
2010
2011    case 0x41:				/* unexpected disconnect aborted command	*/
2012	acornscsi_disconnect_unexpected(host);
2013	return INTR_NEXT_COMMAND;
2014    }
2015
2016    switch (host->scsi.phase) {
2017    case PHASE_CONNECTING:		/* STATE: command removed from issue queue	*/
2018	switch (ssr) {
2019	case 0x11:			/* -> PHASE_CONNECTED				*/
2020	    /* BUS FREE -> SELECTION */
2021	    host->scsi.phase = PHASE_CONNECTED;
2022	    msgqueue_flush(&host->scsi.msgs);
2023	    host->dma.transferred = host->scsi.SCp.scsi_xferred;
2024	    /* 33C93 gives next interrupt indicating bus phase */
2025	    asr = sbic_arm_read(host, SBIC_ASR);
2026	    if (!(asr & ASR_INT))
2027		break;
2028	    ssr = sbic_arm_read(host, SBIC_SSR);
2029	    ADD_STATUS(8, ssr, host->scsi.phase, 1);
2030	    ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, 1);
2031	    goto connected;
2032	    
2033	case 0x42:			/* select timed out				*/
2034					/* -> PHASE_IDLE				*/
2035	    acornscsi_done(host, &host->SCpnt, DID_NO_CONNECT);
2036	    return INTR_NEXT_COMMAND;
2037
2038	case 0x81:			/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2039	    /* BUS FREE -> RESELECTION */
2040	    host->origSCpnt = host->SCpnt;
2041	    host->SCpnt = NULL;
2042	    msgqueue_flush(&host->scsi.msgs);
2043	    acornscsi_reconnect(host);
2044	    break;
2045
2046	default:
2047	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTING, SSR %02X?\n",
2048		    host->host->host_no, acornscsi_target(host), ssr);
2049	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2050	    acornscsi_abortcmd(host, host->SCpnt->tag);
2051	}
2052	return INTR_PROCESSING;
2053
2054    connected:
2055    case PHASE_CONNECTED:		/* STATE: device selected ok			*/
2056	switch (ssr) {
2057#ifdef NONSTANDARD
2058	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2059	    /* SELECTION -> COMMAND */
2060	    acornscsi_sendcommand(host);
2061	    break;
2062
2063	case 0x8b:			/* -> PHASE_STATUS				*/
2064	    /* SELECTION -> STATUS */
2065	    acornscsi_readstatusbyte(host);
2066	    host->scsi.phase = PHASE_STATUSIN;
2067	    break;
2068#endif
2069
2070	case 0x8e:			/* -> PHASE_MSGOUT				*/
2071	    /* SELECTION ->MESSAGE OUT */
2072	    host->scsi.phase = PHASE_MSGOUT;
2073	    acornscsi_buildmessages(host);
2074	    acornscsi_sendmessage(host);
2075	    break;
2076
2077	/* these should not happen */
2078	case 0x85:			/* target disconnected				*/
2079	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2080	    break;
2081
2082	default:
2083	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTED, SSR %02X?\n",
2084		    host->host->host_no, acornscsi_target(host), ssr);
2085	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2086	    acornscsi_abortcmd(host, host->SCpnt->tag);
2087	}
2088	return INTR_PROCESSING;
2089
2090    case PHASE_MSGOUT:			/* STATE: connected & sent IDENTIFY message	*/
2091	/*
2092	 * SCSI standard says that MESSAGE OUT phases can be followed by a
2093	 * DATA phase, STATUS phase, MESSAGE IN phase or COMMAND phase
2094	 */
2095	switch (ssr) {
2096	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2097	case 0x1a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2098	    /* MESSAGE OUT -> COMMAND */
2099	    acornscsi_sendcommand(host);
2100	    break;
2101
2102	case 0x8b:			/* -> PHASE_STATUS				*/
2103	case 0x1b:			/* -> PHASE_STATUS				*/
2104	    /* MESSAGE OUT -> STATUS */
2105	    acornscsi_readstatusbyte(host);
2106	    host->scsi.phase = PHASE_STATUSIN;
2107	    break;
2108
2109	case 0x8e:			/* -> PHASE_MSGOUT				*/
2110	    /* MESSAGE_OUT(MESSAGE_IN) ->MESSAGE OUT */
2111	    acornscsi_sendmessage(host);
2112	    break;
2113
2114	case 0x4f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2115	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2116	    /* MESSAGE OUT -> MESSAGE IN */
2117	    acornscsi_message(host);
2118	    break;
2119
2120	default:
2121	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGOUT, SSR %02X?\n",
2122		    host->host->host_no, acornscsi_target(host), ssr);
2123	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2124	}
2125	return INTR_PROCESSING;
2126
2127    case PHASE_COMMAND: 		/* STATE: connected & command sent		*/
2128	switch (ssr) {
2129	case 0x18:			/* -> PHASE_DATAOUT				*/
2130	    /* COMMAND -> DATA OUT */
2131	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2132		acornscsi_abortcmd(host, host->SCpnt->tag);
2133	    acornscsi_dma_setup(host, DMA_OUT);
2134	    if (!acornscsi_starttransfer(host))
2135		acornscsi_abortcmd(host, host->SCpnt->tag);
2136	    host->scsi.phase = PHASE_DATAOUT;
2137	    return INTR_IDLE;
2138
2139	case 0x19:			/* -> PHASE_DATAIN				*/
2140	    /* COMMAND -> DATA IN */
2141	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2142		acornscsi_abortcmd(host, host->SCpnt->tag);
2143	    acornscsi_dma_setup(host, DMA_IN);
2144	    if (!acornscsi_starttransfer(host))
2145		acornscsi_abortcmd(host, host->SCpnt->tag);
2146	    host->scsi.phase = PHASE_DATAIN;
2147	    return INTR_IDLE;
2148
2149	case 0x1b:			/* -> PHASE_STATUS				*/
2150	    /* COMMAND -> STATUS */
2151	    acornscsi_readstatusbyte(host);
2152	    host->scsi.phase = PHASE_STATUSIN;
2153	    break;
2154
2155	case 0x1e:			/* -> PHASE_MSGOUT				*/
2156	    /* COMMAND -> MESSAGE OUT */
2157	    acornscsi_sendmessage(host);
2158	    break;
2159
2160	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2161	    /* COMMAND -> MESSAGE IN */
2162	    acornscsi_message(host);
2163	    break;
2164
2165	default:
2166	    printk(KERN_ERR "scsi%d.%c: PHASE_COMMAND, SSR %02X?\n",
2167		    host->host->host_no, acornscsi_target(host), ssr);
2168	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2169	}
2170	return INTR_PROCESSING;
2171
2172    case PHASE_DISCONNECT:		/* STATE: connected, received DISCONNECT msg	*/
2173	if (ssr == 0x85) {		/* -> PHASE_IDLE				*/
2174	    host->scsi.disconnectable = 1;
2175	    host->scsi.reconnected.tag = 0;
2176	    host->scsi.phase = PHASE_IDLE;
2177	    host->stats.disconnects += 1;
2178	} else {
2179	    printk(KERN_ERR "scsi%d.%c: PHASE_DISCONNECT, SSR %02X instead of disconnect?\n",
2180		    host->host->host_no, acornscsi_target(host), ssr);
2181	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2182	}
2183	return INTR_NEXT_COMMAND;
2184
2185    case PHASE_IDLE:			/* STATE: disconnected				*/
2186	if (ssr == 0x81)		/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2187	    acornscsi_reconnect(host);
2188	else {
2189	    printk(KERN_ERR "scsi%d.%c: PHASE_IDLE, SSR %02X while idle?\n",
2190		    host->host->host_no, acornscsi_target(host), ssr);
2191	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2192	}
2193	return INTR_PROCESSING;
2194
2195    case PHASE_RECONNECTED:		/* STATE: device reconnected to initiator	*/
2196	/*
2197	 * Command reconnected - if MESGIN, get message - it may be
2198	 * the tag.  If not, get command out of disconnected queue
2199	 */
2200	/*
2201	 * If we reconnected and we're not in MESSAGE IN phase after IDENTIFY,
2202	 * reconnect I_T_L command
2203	 */
2204	if (ssr != 0x8f && !acornscsi_reconnect_finish(host))
2205	    return INTR_IDLE;
2206	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
2207	switch (ssr) {
2208	case 0x88:			/* data out phase				*/
2209					/* -> PHASE_DATAOUT				*/
2210	    /* MESSAGE IN -> DATA OUT */
2211	    acornscsi_dma_setup(host, DMA_OUT);
2212	    if (!acornscsi_starttransfer(host))
2213		acornscsi_abortcmd(host, host->SCpnt->tag);
2214	    host->scsi.phase = PHASE_DATAOUT;
2215	    return INTR_IDLE;
2216
2217	case 0x89:			/* data in phase				*/
2218					/* -> PHASE_DATAIN				*/
2219	    /* MESSAGE IN -> DATA IN */
2220	    acornscsi_dma_setup(host, DMA_IN);
2221	    if (!acornscsi_starttransfer(host))
2222		acornscsi_abortcmd(host, host->SCpnt->tag);
2223	    host->scsi.phase = PHASE_DATAIN;
2224	    return INTR_IDLE;
2225
2226	case 0x8a:			/* command out					*/
2227	    /* MESSAGE IN -> COMMAND */
2228	    acornscsi_sendcommand(host);/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2229	    break;
2230
2231	case 0x8b:			/* status in					*/
2232					/* -> PHASE_STATUSIN				*/
2233	    /* MESSAGE IN -> STATUS */
2234	    acornscsi_readstatusbyte(host);
2235	    host->scsi.phase = PHASE_STATUSIN;
2236	    break;
2237
2238	case 0x8e:			/* message out					*/
2239					/* -> PHASE_MSGOUT				*/
2240	    /* MESSAGE IN -> MESSAGE OUT */
2241	    acornscsi_sendmessage(host);
2242	    break;
2243
2244	case 0x8f:			/* message in					*/
2245	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2246	    break;
2247
2248	default:
2249	    printk(KERN_ERR "scsi%d.%c: PHASE_RECONNECTED, SSR %02X after reconnect?\n",
2250		    host->host->host_no, acornscsi_target(host), ssr);
2251	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2252	}
2253	return INTR_PROCESSING;
2254
2255    case PHASE_DATAIN:			/* STATE: transferred data in			*/
2256	/*
2257	 * This is simple - if we disconnect then the DMA address & count is
2258	 * correct.
2259	 */
2260	switch (ssr) {
2261	case 0x19:			/* -> PHASE_DATAIN				*/
2262	case 0x89:			/* -> PHASE_DATAIN				*/
2263	    acornscsi_abortcmd(host, host->SCpnt->tag);
2264	    return INTR_IDLE;
2265
2266	case 0x1b:			/* -> PHASE_STATUSIN				*/
2267	case 0x4b:			/* -> PHASE_STATUSIN				*/
2268	case 0x8b:			/* -> PHASE_STATUSIN				*/
2269	    /* DATA IN -> STATUS */
2270	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2271					  acornscsi_sbic_xfcount(host);
2272	    acornscsi_dma_stop(host);
2273	    acornscsi_readstatusbyte(host);
2274	    host->scsi.phase = PHASE_STATUSIN;
2275	    break;
2276
2277	case 0x1e:			/* -> PHASE_MSGOUT				*/
2278	case 0x4e:			/* -> PHASE_MSGOUT				*/
2279	case 0x8e:			/* -> PHASE_MSGOUT				*/
2280	    /* DATA IN -> MESSAGE OUT */
2281	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2282					  acornscsi_sbic_xfcount(host);
2283	    acornscsi_dma_stop(host);
2284	    acornscsi_sendmessage(host);
2285	    break;
2286
2287	case 0x1f:			/* message in					*/
2288	case 0x4f:			/* message in					*/
2289	case 0x8f:			/* message in					*/
2290	    /* DATA IN -> MESSAGE IN */
2291	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2292					  acornscsi_sbic_xfcount(host);
2293	    acornscsi_dma_stop(host);
2294	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2295	    break;
2296
2297	default:
2298	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAIN, SSR %02X?\n",
2299		    host->host->host_no, acornscsi_target(host), ssr);
2300	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2301	}
2302	return INTR_PROCESSING;
2303
2304    case PHASE_DATAOUT: 		/* STATE: transferred data out			*/
2305	/*
2306	 * This is more complicated - if we disconnect, the DMA could be 12
2307	 * bytes ahead of us.  We need to correct this.
2308	 */
2309	switch (ssr) {
2310	case 0x18:			/* -> PHASE_DATAOUT				*/
2311	case 0x88:			/* -> PHASE_DATAOUT				*/
2312	    acornscsi_abortcmd(host, host->SCpnt->tag);
2313	    return INTR_IDLE;
2314
2315	case 0x1b:			/* -> PHASE_STATUSIN				*/
2316	case 0x4b:			/* -> PHASE_STATUSIN				*/
2317	case 0x8b:			/* -> PHASE_STATUSIN				*/
2318	    /* DATA OUT -> STATUS */
2319	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2320					  acornscsi_sbic_xfcount(host);
2321	    acornscsi_dma_stop(host);
2322	    acornscsi_dma_adjust(host);
2323	    acornscsi_readstatusbyte(host);
2324	    host->scsi.phase = PHASE_STATUSIN;
2325	    break;
2326
2327	case 0x1e:			/* -> PHASE_MSGOUT				*/
2328	case 0x4e:			/* -> PHASE_MSGOUT				*/
2329	case 0x8e:			/* -> PHASE_MSGOUT				*/
2330	    /* DATA OUT -> MESSAGE OUT */
2331	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2332					  acornscsi_sbic_xfcount(host);
2333	    acornscsi_dma_stop(host);
2334	    acornscsi_dma_adjust(host);
2335	    acornscsi_sendmessage(host);
2336	    break;
2337
2338	case 0x1f:			/* message in					*/
2339	case 0x4f:			/* message in					*/
2340	case 0x8f:			/* message in					*/
2341	    /* DATA OUT -> MESSAGE IN */
2342	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2343					  acornscsi_sbic_xfcount(host);
2344	    acornscsi_dma_stop(host);
2345	    acornscsi_dma_adjust(host);
2346	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2347	    break;
2348
2349	default:
2350	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAOUT, SSR %02X?\n",
2351		    host->host->host_no, acornscsi_target(host), ssr);
2352	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2353	}
2354	return INTR_PROCESSING;
2355
2356    case PHASE_STATUSIN:		/* STATE: status in complete			*/
2357	switch (ssr) {
2358	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2359	case 0x8f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2360	    /* STATUS -> MESSAGE IN */
2361	    acornscsi_message(host);
2362	    break;
2363
2364	case 0x1e:			/* -> PHASE_MSGOUT				*/
2365	case 0x8e:			/* -> PHASE_MSGOUT				*/
2366	    /* STATUS -> MESSAGE OUT */
2367	    acornscsi_sendmessage(host);
2368	    break;
2369
2370	default:
2371	    printk(KERN_ERR "scsi%d.%c: PHASE_STATUSIN, SSR %02X instead of MESSAGE_IN?\n",
2372		    host->host->host_no, acornscsi_target(host), ssr);
2373	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2374	}
2375	return INTR_PROCESSING;
2376
2377    case PHASE_MSGIN:			/* STATE: message in				*/
2378	switch (ssr) {
2379	case 0x1e:			/* -> PHASE_MSGOUT				*/
2380	case 0x4e:			/* -> PHASE_MSGOUT				*/
2381	case 0x8e:			/* -> PHASE_MSGOUT				*/
2382	    /* MESSAGE IN -> MESSAGE OUT */
2383	    acornscsi_sendmessage(host);
2384	    break;
2385
2386	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2387	case 0x2f:
2388	case 0x4f:
2389	case 0x8f:
2390	    acornscsi_message(host);
2391	    break;
2392
2393	case 0x85:
2394	    printk("scsi%d.%c: strange message in disconnection\n",
2395		host->host->host_no, acornscsi_target(host));
2396	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2397	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2398	    break;
2399
2400	default:
2401	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGIN, SSR %02X after message in?\n",
2402		    host->host->host_no, acornscsi_target(host), ssr);
2403	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2404	}
2405	return INTR_PROCESSING;
2406
2407    case PHASE_DONE:			/* STATE: received status & message		*/
2408	switch (ssr) {
2409	case 0x85:			/* -> PHASE_IDLE				*/
2410	    acornscsi_done(host, &host->SCpnt, DID_OK);
2411	    return INTR_NEXT_COMMAND;
2412
2413	case 0x1e:
2414	case 0x8e:
2415	    acornscsi_sendmessage(host);
2416	    break;
2417
2418	default:
2419	    printk(KERN_ERR "scsi%d.%c: PHASE_DONE, SSR %02X instead of disconnect?\n",
2420		    host->host->host_no, acornscsi_target(host), ssr);
2421	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2422	}
2423	return INTR_PROCESSING;
2424
2425    case PHASE_ABORTED:
2426	switch (ssr) {
2427	case 0x85:
2428	    if (host->SCpnt)
2429		acornscsi_done(host, &host->SCpnt, DID_ABORT);
2430	    else {
2431		clear_bit(host->scsi.reconnected.target * 8 + host->scsi.reconnected.lun,
2432			  host->busyluns);
2433		host->scsi.phase = PHASE_IDLE;
2434	    }
2435	    return INTR_NEXT_COMMAND;
2436
2437	case 0x1e:
2438	case 0x2e:
2439	case 0x4e:
2440	case 0x8e:
2441	    acornscsi_sendmessage(host);
2442	    break;
2443
2444	default:
2445	    printk(KERN_ERR "scsi%d.%c: PHASE_ABORTED, SSR %02X?\n",
2446		    host->host->host_no, acornscsi_target(host), ssr);
2447	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2448	}
2449	return INTR_PROCESSING;
2450
2451    default:
2452	printk(KERN_ERR "scsi%d.%c: unknown driver phase %d\n",
2453		host->host->host_no, acornscsi_target(host), ssr);
2454	acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2455    }
2456    return INTR_PROCESSING;
2457}
2458
2459/*
2460 * Prototype: void acornscsi_intr(int irq, void *dev_id)
2461 * Purpose  : handle interrupts from Acorn SCSI card
2462 * Params   : irq    - interrupt number
2463 *	      dev_id - device specific data (AS_Host structure)
2464 */
2465static irqreturn_t
2466acornscsi_intr(int irq, void *dev_id)
2467{
2468    AS_Host *host = (AS_Host *)dev_id;
2469    intr_ret_t ret;
2470    int iostatus;
2471    int in_irq = 0;
2472
2473    do {
2474	ret = INTR_IDLE;
2475
2476	iostatus = readb(host->fast + INT_REG);
2477
2478	if (iostatus & 2) {
2479	    acornscsi_dma_intr(host);
2480	    iostatus = readb(host->fast + INT_REG);
2481	}
2482
2483	if (iostatus & 8)
2484	    ret = acornscsi_sbicintr(host, in_irq);
2485
2486	/*
2487	 * If we have a transfer pending, start it.
2488	 * Only start it if the interface has already started transferring
2489	 * it's data
2490	 */
2491	if (host->dma.xfer_required)
2492	    acornscsi_dma_xfer(host);
2493
2494	if (ret == INTR_NEXT_COMMAND)
2495	    ret = acornscsi_kick(host);
2496
2497	in_irq = 1;
2498    } while (ret != INTR_IDLE);
2499
2500    return IRQ_HANDLED;
2501}
2502
2503/*=============================================================================================
2504 * Interfaces between interrupt handler and rest of scsi code
2505 */
2506
2507/*
2508 * Function : acornscsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2509 * Purpose  : queues a SCSI command
2510 * Params   : cmd  - SCSI command
2511 *	      done - function called on completion, with pointer to command descriptor
2512 * Returns  : 0, or < 0 on error.
2513 */
2514static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt,
2515		       void (*done)(struct scsi_cmnd *))
2516{
2517    AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2518
2519    if (!done) {
2520	/* there should be some way of rejecting errors like this without panicing... */
2521	panic("scsi%d: queuecommand called with NULL done function [cmd=%p]",
2522		host->host->host_no, SCpnt);
2523	return -EINVAL;
2524    }
2525
2526#if (DEBUG & DEBUG_NO_WRITE)
2527    if (acornscsi_cmdtype(SCpnt->cmnd[0]) == CMD_WRITE && (NO_WRITE & (1 << SCpnt->device->id))) {
2528	printk(KERN_CRIT "scsi%d.%c: WRITE attempted with NO_WRITE flag set\n",
2529	    host->host->host_no, '0' + SCpnt->device->id);
2530	SCpnt->result = DID_NO_CONNECT << 16;
2531	done(SCpnt);
2532	return 0;
2533    }
2534#endif
2535
2536    SCpnt->scsi_done = done;
2537    SCpnt->host_scribble = NULL;
2538    SCpnt->result = 0;
2539    SCpnt->tag = 0;
2540    SCpnt->SCp.phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
2541    SCpnt->SCp.sent_command = 0;
2542    SCpnt->SCp.scsi_xferred = 0;
2543
2544    init_SCp(SCpnt);
2545
2546    host->stats.queues += 1;
2547
2548    {
2549	unsigned long flags;
2550
2551	if (!queue_add_cmd_ordered(&host->queues.issue, SCpnt)) {
2552	    SCpnt->result = DID_ERROR << 16;
2553	    done(SCpnt);
2554	    return 0;
2555	}
2556	local_irq_save(flags);
2557	if (host->scsi.phase == PHASE_IDLE)
2558	    acornscsi_kick(host);
2559	local_irq_restore(flags);
2560    }
2561    return 0;
2562}
2563
2564DEF_SCSI_QCMD(acornscsi_queuecmd)
2565
2566/*
2567 * Prototype: void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1, struct scsi_cmnd **SCpntp2, int result)
2568 * Purpose  : pass a result to *SCpntp1, and check if *SCpntp1 = *SCpntp2
2569 * Params   : SCpntp1 - pointer to command to return
2570 *	      SCpntp2 - pointer to command to check
2571 *	      result  - result to pass back to mid-level done function
2572 * Returns  : *SCpntp2 = NULL if *SCpntp1 is the same command structure as *SCpntp2.
2573 */
2574static inline void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1,
2575					  struct scsi_cmnd **SCpntp2,
2576					  int result)
2577{
2578	struct scsi_cmnd *SCpnt = *SCpntp1;
2579
2580    if (SCpnt) {
2581	*SCpntp1 = NULL;
2582
2583	SCpnt->result = result;
2584	SCpnt->scsi_done(SCpnt);
2585    }
2586
2587    if (SCpnt == *SCpntp2)
2588	*SCpntp2 = NULL;
2589}
2590
2591enum res_abort { res_not_running, res_success, res_success_clear, res_snooze };
2592
2593/*
2594 * Prototype: enum res acornscsi_do_abort(struct scsi_cmnd *SCpnt)
2595 * Purpose  : abort a command on this host
2596 * Params   : SCpnt - command to abort
2597 * Returns  : our abort status
2598 */
2599static enum res_abort acornscsi_do_abort(AS_Host *host, struct scsi_cmnd *SCpnt)
2600{
2601	enum res_abort res = res_not_running;
2602
2603	if (queue_remove_cmd(&host->queues.issue, SCpnt)) {
2604		/*
2605		 * The command was on the issue queue, and has not been
2606		 * issued yet.  We can remove the command from the queue,
2607		 * and acknowledge the abort.  Neither the devices nor the
2608		 * interface know about the command.
2609		 */
2610//#if (DEBUG & DEBUG_ABORT)
2611		printk("on issue queue ");
2612//#endif
2613		res = res_success;
2614	} else if (queue_remove_cmd(&host->queues.disconnected, SCpnt)) {
2615		/*
2616		 * The command was on the disconnected queue.  Simply
2617		 * acknowledge the abort condition, and when the target
2618		 * reconnects, we will give it an ABORT message.  The
2619		 * target should then disconnect, and we will clear
2620		 * the busylun bit.
2621		 */
2622//#if (DEBUG & DEBUG_ABORT)
2623		printk("on disconnected queue ");
2624//#endif
2625		res = res_success;
2626	} else if (host->SCpnt == SCpnt) {
2627		unsigned long flags;
2628
2629//#if (DEBUG & DEBUG_ABORT)
2630		printk("executing ");
2631//#endif
2632
2633		local_irq_save(flags);
2634		switch (host->scsi.phase) {
2635		/*
2636		 * If the interface is idle, and the command is 'disconnectable',
2637		 * then it is the same as on the disconnected queue.  We simply
2638		 * remove all traces of the command.  When the target reconnects,
2639		 * we will give it an ABORT message since the command could not
2640		 * be found.  When the target finally disconnects, we will clear
2641		 * the busylun bit.
2642		 */
2643		case PHASE_IDLE:
2644			if (host->scsi.disconnectable) {
2645				host->scsi.disconnectable = 0;
2646				host->SCpnt = NULL;
2647				res = res_success;
2648			}
2649			break;
2650
2651		/*
2652		 * If the command has connected and done nothing further,
2653		 * simply force a disconnect.  We also need to clear the
2654		 * busylun bit.
2655		 */
2656		case PHASE_CONNECTED:
2657			sbic_arm_write(host, SBIC_CMND, CMND_DISCONNECT);
2658			host->SCpnt = NULL;
2659			res = res_success_clear;
2660			break;
2661
2662		default:
2663			acornscsi_abortcmd(host, host->SCpnt->tag);
2664			res = res_snooze;
2665		}
2666		local_irq_restore(flags);
2667	} else if (host->origSCpnt == SCpnt) {
2668		/*
2669		 * The command will be executed next, but a command
2670		 * is currently using the interface.  This is similar to
2671		 * being on the issue queue, except the busylun bit has
2672		 * been set.
2673		 */
2674		host->origSCpnt = NULL;
2675//#if (DEBUG & DEBUG_ABORT)
2676		printk("waiting for execution ");
2677//#endif
2678		res = res_success_clear;
2679	} else
2680		printk("unknown ");
2681
2682	return res;
2683}
2684
2685/*
2686 * Prototype: int acornscsi_abort(struct scsi_cmnd *SCpnt)
2687 * Purpose  : abort a command on this host
2688 * Params   : SCpnt - command to abort
2689 * Returns  : one of SCSI_ABORT_ macros
2690 */
2691int acornscsi_abort(struct scsi_cmnd *SCpnt)
2692{
2693	AS_Host *host = (AS_Host *) SCpnt->device->host->hostdata;
2694	int result;
2695
2696	host->stats.aborts += 1;
2697
2698#if (DEBUG & DEBUG_ABORT)
2699	{
2700		int asr, ssr;
2701		asr = sbic_arm_read(host, SBIC_ASR);
2702		ssr = sbic_arm_read(host, SBIC_SSR);
2703
2704		printk(KERN_WARNING "acornscsi_abort: ");
2705		print_sbic_status(asr, ssr, host->scsi.phase);
2706		acornscsi_dumplog(host, SCpnt->device->id);
2707	}
2708#endif
2709
2710	printk("scsi%d: ", host->host->host_no);
2711
2712	switch (acornscsi_do_abort(host, SCpnt)) {
2713	/*
2714	 * We managed to find the command and cleared it out.
2715	 * We do not expect the command to be executing on the
2716	 * target, but we have set the busylun bit.
2717	 */
2718	case res_success_clear:
2719//#if (DEBUG & DEBUG_ABORT)
2720		printk("clear ");
2721//#endif
2722		clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
2723
2724	/*
2725	 * We found the command, and cleared it out.  Either
2726	 * the command is still known to be executing on the
2727	 * target, or the busylun bit is not set.
2728	 */
2729	case res_success:
2730//#if (DEBUG & DEBUG_ABORT)
2731		printk("success\n");
2732//#endif
2733		result = SUCCESS;
2734		break;
2735
2736	/*
2737	 * We did find the command, but unfortunately we couldn't
2738	 * unhook it from ourselves.  Wait some more, and if it
2739	 * still doesn't complete, reset the interface.
2740	 */
2741	case res_snooze:
2742//#if (DEBUG & DEBUG_ABORT)
2743		printk("snooze\n");
2744//#endif
2745		result = FAILED;
2746		break;
2747
2748	/*
2749	 * The command could not be found (either because it completed,
2750	 * or it got dropped.
2751	 */
2752	default:
2753	case res_not_running:
2754		acornscsi_dumplog(host, SCpnt->device->id);
2755		result = FAILED;
2756//#if (DEBUG & DEBUG_ABORT)
2757		printk("not running\n");
2758//#endif
2759		break;
2760	}
2761
2762	return result;
2763}
2764
2765/*
2766 * Prototype: int acornscsi_reset(struct scsi_cmnd *SCpnt)
2767 * Purpose  : reset a command on this host/reset this host
2768 * Params   : SCpnt  - command causing reset
2769 * Returns  : one of SCSI_RESET_ macros
2770 */
2771int acornscsi_bus_reset(struct scsi_cmnd *SCpnt)
2772{
2773	AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2774	struct scsi_cmnd *SCptr;
2775    
2776    host->stats.resets += 1;
2777
2778#if (DEBUG & DEBUG_RESET)
2779    {
2780	int asr, ssr;
2781
2782	asr = sbic_arm_read(host, SBIC_ASR);
2783	ssr = sbic_arm_read(host, SBIC_SSR);
2784
2785	printk(KERN_WARNING "acornscsi_reset: ");
2786	print_sbic_status(asr, ssr, host->scsi.phase);
2787	acornscsi_dumplog(host, SCpnt->device->id);
2788    }
2789#endif
2790
2791    acornscsi_dma_stop(host);
2792
2793    /*
2794     * do hard reset.  This resets all devices on this host, and so we
2795     * must set the reset status on all commands.
2796     */
2797    acornscsi_resetcard(host);
2798
2799    while ((SCptr = queue_remove(&host->queues.disconnected)) != NULL)
2800	;
2801
2802    return SUCCESS;
2803}
2804
2805/*==============================================================================================
2806 * initialisation & miscellaneous support
2807 */
2808
2809/*
2810 * Function: char *acornscsi_info(struct Scsi_Host *host)
2811 * Purpose : return a string describing this interface
2812 * Params  : host - host to give information on
2813 * Returns : a constant string
2814 */
2815const
2816char *acornscsi_info(struct Scsi_Host *host)
2817{
2818    static char string[100], *p;
2819
2820    p = string;
2821    
2822    p += sprintf(string, "%s at port %08lX irq %d v%d.%d.%d"
2823#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2824    " SYNC"
2825#endif
2826#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2827    " TAG"
2828#endif
2829#ifdef CONFIG_SCSI_ACORNSCSI_LINK
2830    " LINK"
2831#endif
2832#if (DEBUG & DEBUG_NO_WRITE)
2833    " NOWRITE (" __stringify(NO_WRITE) ")"
2834#endif
2835		, host->hostt->name, host->io_port, host->irq,
2836		VER_MAJOR, VER_MINOR, VER_PATCH);
2837    return string;
2838}
2839
2840int acornscsi_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset,
2841			int length, int inout)
2842{
2843    int pos, begin = 0, devidx;
2844    struct scsi_device *scd;
2845    AS_Host *host;
2846    char *p = buffer;
2847
2848    if (inout == 1)
2849	return -EINVAL;
2850
2851    host  = (AS_Host *)instance->hostdata;
2852    
2853    p += sprintf(p, "AcornSCSI driver v%d.%d.%d"
2854#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2855    " SYNC"
2856#endif
2857#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2858    " TAG"
2859#endif
2860#ifdef CONFIG_SCSI_ACORNSCSI_LINK
2861    " LINK"
2862#endif
2863#if (DEBUG & DEBUG_NO_WRITE)
2864    " NOWRITE (" __stringify(NO_WRITE) ")"
2865#endif
2866		"\n\n", VER_MAJOR, VER_MINOR, VER_PATCH);
2867
2868    p += sprintf(p,	"SBIC: WD33C93A  Address: %p    IRQ : %d\n",
2869			host->base + SBIC_REGIDX, host->scsi.irq);
2870#ifdef USE_DMAC
2871    p += sprintf(p,	"DMAC: uPC71071  Address: %p  IRQ : %d\n\n",
2872			host->base + DMAC_OFFSET, host->scsi.irq);
2873#endif
2874
2875    p += sprintf(p,	"Statistics:\n"
2876			"Queued commands: %-10u    Issued commands: %-10u\n"
2877			"Done commands  : %-10u    Reads          : %-10u\n"
2878			"Writes         : %-10u    Others         : %-10u\n"
2879			"Disconnects    : %-10u    Aborts         : %-10u\n"
2880			"Resets         : %-10u\n\nLast phases:",
2881			host->stats.queues,		host->stats.removes,
2882			host->stats.fins,		host->stats.reads,
2883			host->stats.writes,		host->stats.miscs,
2884			host->stats.disconnects,	host->stats.aborts,
2885			host->stats.resets);
2886
2887    for (devidx = 0; devidx < 9; devidx ++) {
2888	unsigned int statptr, prev;
2889
2890	p += sprintf(p, "\n%c:", devidx == 8 ? 'H' : ('0' + devidx));
2891	statptr = host->status_ptr[devidx] - 10;
2892
2893	if ((signed int)statptr < 0)
2894	    statptr += STATUS_BUFFER_SIZE;
2895
2896	prev = host->status[devidx][statptr].when;
2897
2898	for (; statptr != host->status_ptr[devidx]; statptr = (statptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
2899	    if (host->status[devidx][statptr].when) {
2900		p += sprintf(p, "%c%02X:%02X+%2ld",
2901			host->status[devidx][statptr].irq ? '-' : ' ',
2902			host->status[devidx][statptr].ph,
2903			host->status[devidx][statptr].ssr,
2904			(host->status[devidx][statptr].when - prev) < 100 ?
2905				(host->status[devidx][statptr].when - prev) : 99);
2906		prev = host->status[devidx][statptr].when;
2907	    }
2908	}
2909    }
2910
2911    p += sprintf(p, "\nAttached devices:\n");
2912
2913    shost_for_each_device(scd, instance) {
2914	p += sprintf(p, "Device/Lun TaggedQ      Sync\n");
2915	p += sprintf(p, "     %d/%d   ", scd->id, scd->lun);
2916	if (scd->tagged_supported)
2917		p += sprintf(p, "%3sabled(%3d) ",
2918			     scd->simple_tags ? "en" : "dis",
2919			     scd->current_tag);
2920	else
2921		p += sprintf(p, "unsupported  ");
2922
2923	if (host->device[scd->id].sync_xfer & 15)
2924		p += sprintf(p, "offset %d, %d ns\n",
2925			     host->device[scd->id].sync_xfer & 15,
2926			     acornscsi_getperiod(host->device[scd->id].sync_xfer));
2927	else
2928		p += sprintf(p, "async\n");
2929
2930	pos = p - buffer;
2931	if (pos + begin < offset) {
2932	    begin += pos;
2933	    p = buffer;
2934	}
2935	pos = p - buffer;
2936	if (pos + begin > offset + length) {
2937	    scsi_device_put(scd);
2938	    break;
2939	}
2940    }
2941
2942    pos = p - buffer;
2943
2944    *start = buffer + (offset - begin);
2945    pos -= offset - begin;
2946
2947    if (pos > length)
2948	pos = length;
2949
2950    return pos;
2951}
2952
2953static struct scsi_host_template acornscsi_template = {
2954	.module			= THIS_MODULE,
2955	.proc_info		= acornscsi_proc_info,
2956	.name			= "AcornSCSI",
2957	.info			= acornscsi_info,
2958	.queuecommand		= acornscsi_queuecmd,
2959	.eh_abort_handler	= acornscsi_abort,
2960	.eh_bus_reset_handler	= acornscsi_bus_reset,
2961	.can_queue		= 16,
2962	.this_id		= 7,
2963	.sg_tablesize		= SG_ALL,
2964	.cmd_per_lun		= 2,
2965	.use_clustering		= DISABLE_CLUSTERING,
2966	.proc_name		= "acornscsi",
2967};
2968
2969static int __devinit
2970acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
2971{
2972	struct Scsi_Host *host;
2973	AS_Host *ashost;
2974	int ret;
2975
2976	ret = ecard_request_resources(ec);
2977	if (ret)
2978		goto out;
2979
2980	host = scsi_host_alloc(&acornscsi_template, sizeof(AS_Host));
2981	if (!host) {
2982		ret = -ENOMEM;
2983		goto out_release;
2984	}
2985
2986	ashost = (AS_Host *)host->hostdata;
2987
2988	ashost->base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
2989	ashost->fast = ecardm_iomap(ec, ECARD_RES_IOCFAST, 0, 0);
2990	if (!ashost->base || !ashost->fast)
2991		goto out_put;
2992
2993	host->irq = ec->irq;
2994	ashost->host = host;
2995	ashost->scsi.irq = host->irq;
2996
2997	ec->irqaddr	= ashost->fast + INT_REG;
2998	ec->irqmask	= 0x0a;
2999
3000	ret = request_irq(host->irq, acornscsi_intr, IRQF_DISABLED, "acornscsi", ashost);
3001	if (ret) {
3002		printk(KERN_CRIT "scsi%d: IRQ%d not free: %d\n",
3003			host->host_no, ashost->scsi.irq, ret);
3004		goto out_put;
3005	}
3006
3007	memset(&ashost->stats, 0, sizeof (ashost->stats));
3008	queue_initialise(&ashost->queues.issue);
3009	queue_initialise(&ashost->queues.disconnected);
3010	msgqueue_initialise(&ashost->scsi.msgs);
3011
3012	acornscsi_resetcard(ashost);
3013
3014	ret = scsi_add_host(host, &ec->dev);
3015	if (ret)
3016		goto out_irq;
3017
3018	scsi_scan_host(host);
3019	goto out;
3020
3021 out_irq:
3022	free_irq(host->irq, ashost);
3023	msgqueue_free(&ashost->scsi.msgs);
3024	queue_free(&ashost->queues.disconnected);
3025	queue_free(&ashost->queues.issue);
3026 out_put:
3027	ecardm_iounmap(ec, ashost->fast);
3028	ecardm_iounmap(ec, ashost->base);
3029	scsi_host_put(host);
3030 out_release:
3031	ecard_release_resources(ec);
3032 out:
3033	return ret;
3034}
3035
3036static void __devexit acornscsi_remove(struct expansion_card *ec)
3037{
3038	struct Scsi_Host *host = ecard_get_drvdata(ec);
3039	AS_Host *ashost = (AS_Host *)host->hostdata;
3040
3041	ecard_set_drvdata(ec, NULL);
3042	scsi_remove_host(host);
3043
3044	/*
3045	 * Put card into RESET state
3046	 */
3047	writeb(0x80, ashost->fast + PAGE_REG);
3048
3049	free_irq(host->irq, ashost);
3050
3051	msgqueue_free(&ashost->scsi.msgs);
3052	queue_free(&ashost->queues.disconnected);
3053	queue_free(&ashost->queues.issue);
3054	ecardm_iounmap(ec, ashost->fast);
3055	ecardm_iounmap(ec, ashost->base);
3056	scsi_host_put(host);
3057	ecard_release_resources(ec);
3058}
3059
3060static const struct ecard_id acornscsi_cids[] = {
3061	{ MANU_ACORN, PROD_ACORN_SCSI },
3062	{ 0xffff, 0xffff },
3063};
3064
3065static struct ecard_driver acornscsi_driver = {
3066	.probe		= acornscsi_probe,
3067	.remove		= __devexit_p(acornscsi_remove),
3068	.id_table	= acornscsi_cids,
3069	.drv = {
3070		.name		= "acornscsi",
3071	},
3072};
3073
3074static int __init acornscsi_init(void)
3075{
3076	return ecard_register_driver(&acornscsi_driver);
3077}
3078
3079static void __exit acornscsi_exit(void)
3080{
3081	ecard_remove_driver(&acornscsi_driver);
3082}
3083
3084module_init(acornscsi_init);
3085module_exit(acornscsi_exit);
3086
3087MODULE_AUTHOR("Russell King");
3088MODULE_DESCRIPTION("AcornSCSI driver");
3089MODULE_LICENSE("GPL");
v3.5.6
   1/*
   2 *  linux/drivers/acorn/scsi/acornscsi.c
   3 *
   4 *  Acorn SCSI 3 driver
   5 *  By R.M.King.
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * Abandoned using the Select and Transfer command since there were
  12 * some nasty races between our software and the target devices that
  13 * were not easy to solve, and the device errata had a lot of entries
  14 * for this command, some of them quite nasty...
  15 *
  16 * Changelog:
  17 *  26-Sep-1997	RMK	Re-jigged to use the queue module.
  18 *			Re-coded state machine to be based on driver
  19 *			state not scsi state.  Should be easier to debug.
  20 *			Added acornscsi_release to clean up properly.
  21 *			Updated proc/scsi reporting.
  22 *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
  23 *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
  24 *			reconnect race condition causing a warning message.
  25 *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
  26 *  15-Oct-1997	RMK	Improved handling of commands.
  27 *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
  28 *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
  29 *			transitions added to allow dodgy devices to work.
  30 */
  31#define DEBUG_NO_WRITE	1
  32#define DEBUG_QUEUES	2
  33#define DEBUG_DMA	4
  34#define DEBUG_ABORT	8
  35#define DEBUG_DISCON	16
  36#define DEBUG_CONNECT	32
  37#define DEBUG_PHASES	64
  38#define DEBUG_WRITE	128
  39#define DEBUG_LINK	256
  40#define DEBUG_MESSAGES	512
  41#define DEBUG_RESET	1024
  42#define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
  43			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
  44			 DEBUG_DMA|DEBUG_QUEUES)
  45
  46/* DRIVER CONFIGURATION
  47 *
  48 * SCSI-II Tagged queue support.
  49 *
  50 * I don't have any SCSI devices that support it, so it is totally untested
  51 * (except to make sure that it doesn't interfere with any non-tagging
  52 * devices).  It is not fully implemented either - what happens when a
  53 * tagging device reconnects???
  54 *
  55 * You can tell if you have a device that supports tagged queueing my
  56 * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
  57 * as '2 TAG'.
  58 *
  59 * Also note that CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE is normally set in the config
  60 * scripts, but disabled here.  Once debugged, remove the #undef, otherwise to debug,
  61 * comment out the undef.
  62 */
  63#undef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
  64/*
  65 * SCSI-II Linked command support.
  66 *
  67 * The higher level code doesn't support linked commands yet, and so the option
  68 * is undef'd here.
  69 */
  70#undef CONFIG_SCSI_ACORNSCSI_LINK
  71/*
  72 * SCSI-II Synchronous transfer support.
  73 *
  74 * Tried and tested...
  75 *
  76 * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
  77 * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
  78 * DEFAULT_PERIOD - default REQ period.
  79 */
  80#define SDTR_SIZE	12
  81#define SDTR_PERIOD	125
  82#define DEFAULT_PERIOD	500
  83
  84/*
  85 * Debugging information
  86 *
  87 * DEBUG	  - bit mask from list above
  88 * DEBUG_TARGET   - is defined to the target number if you want to debug
  89 *		    a specific target. [only recon/write/dma].
  90 */
  91#define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
  92/* only allow writing to SCSI device 0 */
  93#define NO_WRITE 0xFE
  94/*#define DEBUG_TARGET 2*/
  95/*
  96 * Select timeout time (in 10ms units)
  97 *
  98 * This is the timeout used between the start of selection and the WD33C93
  99 * chip deciding that the device isn't responding.
 100 */
 101#define TIMEOUT_TIME 10
 102/*
 103 * Define this if you want to have verbose explanation of SCSI
 104 * status/messages.
 105 */
 106#undef CONFIG_ACORNSCSI_CONSTANTS
 107/*
 108 * Define this if you want to use the on board DMAC [don't remove this option]
 109 * If not set, then use PIO mode (not currently supported).
 110 */
 111#define USE_DMAC
 112
 113/*
 114 * ====================================================================================
 115 */
 116
 117#ifdef DEBUG_TARGET
 118#define DBG(cmd,xxx...) \
 119  if (cmd->device->id == DEBUG_TARGET) { \
 120    xxx; \
 121  }
 122#else
 123#define DBG(cmd,xxx...) xxx
 124#endif
 125
 126#include <linux/module.h>
 127#include <linux/kernel.h>
 128#include <linux/string.h>
 129#include <linux/signal.h>
 130#include <linux/errno.h>
 131#include <linux/proc_fs.h>
 132#include <linux/ioport.h>
 133#include <linux/blkdev.h>
 134#include <linux/delay.h>
 135#include <linux/interrupt.h>
 136#include <linux/init.h>
 137#include <linux/bitops.h>
 138#include <linux/stringify.h>
 139#include <linux/io.h>
 140
 
 141#include <asm/ecard.h>
 142
 143#include "../scsi.h"
 144#include <scsi/scsi_dbg.h>
 145#include <scsi/scsi_host.h>
 146#include <scsi/scsi_transport_spi.h>
 147#include "acornscsi.h"
 148#include "msgqueue.h"
 149#include "scsi.h"
 150
 151#include <scsi/scsicam.h>
 152
 153#define VER_MAJOR 2
 154#define VER_MINOR 0
 155#define VER_PATCH 6
 156
 157#ifndef ABORT_TAG
 158#define ABORT_TAG 0xd
 159#else
 160#error "Yippee!  ABORT TAG is now defined!  Remove this error!"
 161#endif
 162
 163#ifdef CONFIG_SCSI_ACORNSCSI_LINK
 164#error SCSI2 LINKed commands not supported (yet)!
 165#endif
 166
 167#ifdef USE_DMAC
 168/*
 169 * DMAC setup parameters
 170 */ 
 171#define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
 172#define INIT_DEVCON1	(DEVCON1_BHLD)
 173#define DMAC_READ	(MODECON_READ)
 174#define DMAC_WRITE	(MODECON_WRITE)
 175#define INIT_SBICDMA	(CTRL_DMABURST)
 176
 177#define scsi_xferred	have_data_in
 178
 179/*
 180 * Size of on-board DMA buffer
 181 */
 182#define DMAC_BUFFER_SIZE	65536
 183#endif
 184
 185#define STATUS_BUFFER_TO_PRINT	24
 186
 187unsigned int sdtr_period = SDTR_PERIOD;
 188unsigned int sdtr_size   = SDTR_SIZE;
 189
 190static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
 191			   unsigned int result);
 192static int acornscsi_reconnect_finish(AS_Host *host);
 193static void acornscsi_dma_cleanup(AS_Host *host);
 194static void acornscsi_abortcmd(AS_Host *host, unsigned char tag);
 195
 196/* ====================================================================================
 197 * Miscellaneous
 198 */
 199
 200/* Offsets from MEMC base */
 201#define SBIC_REGIDX	0x2000
 202#define SBIC_REGVAL	0x2004
 203#define DMAC_OFFSET	0x3000
 204
 205/* Offsets from FAST IOC base */
 206#define INT_REG		0x2000
 207#define PAGE_REG	0x3000
 208
 209static inline void sbic_arm_write(AS_Host *host, unsigned int reg, unsigned int value)
 210{
 211    writeb(reg, host->base + SBIC_REGIDX);
 212    writeb(value, host->base + SBIC_REGVAL);
 213}
 214
 215static inline int sbic_arm_read(AS_Host *host, unsigned int reg)
 216{
 217    if(reg == SBIC_ASR)
 218	   return readl(host->base + SBIC_REGIDX) & 255;
 219    writeb(reg, host->base + SBIC_REGIDX);
 220    return readl(host->base + SBIC_REGVAL) & 255;
 221}
 222
 223#define sbic_arm_writenext(host, val)	writeb((val), (host)->base + SBIC_REGVAL)
 224#define sbic_arm_readnext(host) 	readb((host)->base + SBIC_REGVAL)
 225
 226#ifdef USE_DMAC
 227#define dmac_read(host,reg) \
 228	readb((host)->base + DMAC_OFFSET + ((reg) << 2))
 229
 230#define dmac_write(host,reg,value) \
 231	({ writeb((value), (host)->base + DMAC_OFFSET + ((reg) << 2)); })
 232
 233#define dmac_clearintr(host) 	writeb(0, (host)->fast + INT_REG)
 234
 235static inline unsigned int dmac_address(AS_Host *host)
 236{
 237    return dmac_read(host, DMAC_TXADRHI) << 16 |
 238	   dmac_read(host, DMAC_TXADRMD) << 8 |
 239	   dmac_read(host, DMAC_TXADRLO);
 240}
 241
 242static
 243void acornscsi_dumpdma(AS_Host *host, char *where)
 244{
 245	unsigned int mode, addr, len;
 246
 247	mode = dmac_read(host, DMAC_MODECON);
 248	addr = dmac_address(host);
 249	len  = dmac_read(host, DMAC_TXCNTHI) << 8 |
 250	       dmac_read(host, DMAC_TXCNTLO);
 251
 252	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
 253		host->host->host_no, where,
 254		mode, addr, (len + 1) & 0xffff,
 255		dmac_read(host, DMAC_MASKREG));
 256
 257	printk("DMA @%06x, ", host->dma.start_addr);
 258	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
 259		host->scsi.SCp.this_residual);
 260	printk("DT @+%04x ST @+%04x", host->dma.transferred,
 261		host->scsi.SCp.scsi_xferred);
 262	printk("\n");
 263}
 264#endif
 265
 266static
 267unsigned long acornscsi_sbic_xfcount(AS_Host *host)
 268{
 269    unsigned long length;
 270
 271    length = sbic_arm_read(host, SBIC_TRANSCNTH) << 16;
 272    length |= sbic_arm_readnext(host) << 8;
 273    length |= sbic_arm_readnext(host);
 274
 275    return length;
 276}
 277
 278static int
 279acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
 280{
 281	int asr;
 282
 283	do {
 284		asr = sbic_arm_read(host, SBIC_ASR);
 285
 286		if ((asr & stat_mask) == stat)
 287			return 0;
 288
 289		udelay(1);
 290	} while (--timeout);
 291
 292	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);
 293
 294	return -1;
 295}
 296
 297static
 298int acornscsi_sbic_issuecmd(AS_Host *host, int command)
 299{
 300    if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
 301	return -1;
 302
 303    sbic_arm_write(host, SBIC_CMND, command);
 304
 305    return 0;
 306}
 307
 308static void
 309acornscsi_csdelay(unsigned int cs)
 310{
 311    unsigned long target_jiffies, flags;
 312
 313    target_jiffies = jiffies + 1 + cs * HZ / 100;
 314
 315    local_save_flags(flags);
 316    local_irq_enable();
 317
 318    while (time_before(jiffies, target_jiffies)) barrier();
 319
 320    local_irq_restore(flags);
 321}
 322
 323static
 324void acornscsi_resetcard(AS_Host *host)
 325{
 326    unsigned int i, timeout;
 327
 328    /* assert reset line */
 329    host->card.page_reg = 0x80;
 330    writeb(host->card.page_reg, host->fast + PAGE_REG);
 331
 332    /* wait 3 cs.  SCSI standard says 25ms. */
 333    acornscsi_csdelay(3);
 334
 335    host->card.page_reg = 0;
 336    writeb(host->card.page_reg, host->fast + PAGE_REG);
 337
 338    /*
 339     * Should get a reset from the card
 340     */
 341    timeout = 1000;
 342    do {
 343	if (readb(host->fast + INT_REG) & 8)
 344	    break;
 345	udelay(1);
 346    } while (--timeout);
 347
 348    if (timeout == 0)
 349	printk("scsi%d: timeout while resetting card\n",
 350		host->host->host_no);
 351
 352    sbic_arm_read(host, SBIC_ASR);
 353    sbic_arm_read(host, SBIC_SSR);
 354
 355    /* setup sbic - WD33C93A */
 356    sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
 357    sbic_arm_write(host, SBIC_CMND, CMND_RESET);
 358
 359    /*
 360     * Command should cause a reset interrupt
 361     */
 362    timeout = 1000;
 363    do {
 364	if (readb(host->fast + INT_REG) & 8)
 365	    break;
 366	udelay(1);
 367    } while (--timeout);
 368
 369    if (timeout == 0)
 370	printk("scsi%d: timeout while resetting card\n",
 371		host->host->host_no);
 372
 373    sbic_arm_read(host, SBIC_ASR);
 374    if (sbic_arm_read(host, SBIC_SSR) != 0x01)
 375	printk(KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
 376		host->host->host_no);
 377
 378    sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
 379    sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
 380    sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
 381    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
 382
 383    host->card.page_reg = 0x40;
 384    writeb(host->card.page_reg, host->fast + PAGE_REG);
 385
 386    /* setup dmac - uPC71071 */
 387    dmac_write(host, DMAC_INIT, 0);
 388#ifdef USE_DMAC
 389    dmac_write(host, DMAC_INIT, INIT_8BIT);
 390    dmac_write(host, DMAC_CHANNEL, CHANNEL_0);
 391    dmac_write(host, DMAC_DEVCON0, INIT_DEVCON0);
 392    dmac_write(host, DMAC_DEVCON1, INIT_DEVCON1);
 393#endif
 394
 395    host->SCpnt = NULL;
 396    host->scsi.phase = PHASE_IDLE;
 397    host->scsi.disconnectable = 0;
 398
 399    memset(host->busyluns, 0, sizeof(host->busyluns));
 400
 401    for (i = 0; i < 8; i++) {
 402	host->device[i].sync_state = SYNC_NEGOCIATE;
 403	host->device[i].disconnect_ok = 1;
 404    }
 405
 406    /* wait 25 cs.  SCSI standard says 250ms. */
 407    acornscsi_csdelay(25);
 408}
 409
 410/*=============================================================================================
 411 * Utility routines (eg. debug)
 412 */
 413#ifdef CONFIG_ACORNSCSI_CONSTANTS
 414static char *acornscsi_interrupttype[] = {
 415  "rst",  "suc",  "p/a",  "3",
 416  "term", "5",	  "6",	  "7",
 417  "serv", "9",	  "a",	  "b",
 418  "c",	  "d",	  "e",	  "f"
 419};
 420
 421static signed char acornscsi_map[] = {
 422  0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 423 -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 424 12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 425 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 426 15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
 427 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 428 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 429 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 430 21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 431 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 432 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 433 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 434 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 435 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 436 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 437 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
 438};      
 439
 440static char *acornscsi_interruptcode[] = {
 441    /* 0 */
 442    "reset - normal mode",	/* 00 */
 443    "reset - advanced mode",	/* 01 */
 444
 445    /* 2 */
 446    "sel",			/* 11 */
 447    "sel+xfer", 		/* 16 */
 448    "data-out", 		/* 18 */
 449    "data-in",			/* 19 */
 450    "cmd",			/* 1A */
 451    "stat",			/* 1B */
 452    "??-out",			/* 1C */
 453    "??-in",			/* 1D */
 454    "msg-out",			/* 1E */
 455    "msg-in",			/* 1F */
 456
 457    /* 12 */
 458    "/ACK asserted",		/* 20 */
 459    "save-data-ptr",		/* 21 */
 460    "{re}sel",			/* 22 */
 461
 462    /* 15 */
 463    "inv cmd",			/* 40 */
 464    "unexpected disconnect",	/* 41 */
 465    "sel timeout",		/* 42 */
 466    "P err",			/* 43 */
 467    "P err+ATN",		/* 44 */
 468    "bad status byte",		/* 47 */
 469
 470    /* 21 */
 471    "resel, no id",		/* 80 */
 472    "resel",			/* 81 */
 473    "discon",			/* 85 */
 474};
 475
 476static
 477void print_scsi_status(unsigned int ssr)
 478{
 479    if (acornscsi_map[ssr] != -1)
 480	printk("%s:%s",
 481		acornscsi_interrupttype[(ssr >> 4)],
 482		acornscsi_interruptcode[acornscsi_map[ssr]]);
 483    else
 484	printk("%X:%X", ssr >> 4, ssr & 0x0f);    
 485}    
 486#endif
 487
 488static
 489void print_sbic_status(int asr, int ssr, int cmdphase)
 490{
 491#ifdef CONFIG_ACORNSCSI_CONSTANTS
 492    printk("sbic: %c%c%c%c%c%c ",
 493	    asr & ASR_INT ? 'I' : 'i',
 494	    asr & ASR_LCI ? 'L' : 'l',
 495	    asr & ASR_BSY ? 'B' : 'b',
 496	    asr & ASR_CIP ? 'C' : 'c',
 497	    asr & ASR_PE  ? 'P' : 'p',
 498	    asr & ASR_DBR ? 'D' : 'd');
 499    printk("scsi: ");
 500    print_scsi_status(ssr);
 501    printk(" ph %02X\n", cmdphase);
 502#else
 503    printk("sbic: %02X scsi: %X:%X ph: %02X\n",
 504	    asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
 505#endif
 506}
 507
 508static void
 509acornscsi_dumplogline(AS_Host *host, int target, int line)
 510{
 511	unsigned long prev;
 512	signed int ptr;
 513
 514	ptr = host->status_ptr[target] - STATUS_BUFFER_TO_PRINT;
 515	if (ptr < 0)
 516		ptr += STATUS_BUFFER_SIZE;
 517
 518	printk("%c: %3s:", target == 8 ? 'H' : '0' + target,
 519		line == 0 ? "ph" : line == 1 ? "ssr" : "int");
 520
 521	prev = host->status[target][ptr].when;
 522
 523	for (; ptr != host->status_ptr[target]; ptr = (ptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
 524		unsigned long time_diff;
 525
 526		if (!host->status[target][ptr].when)
 527			continue;
 528
 529		switch (line) {
 530		case 0:
 531			printk("%c%02X", host->status[target][ptr].irq ? '-' : ' ',
 532					 host->status[target][ptr].ph);
 533			break;
 534
 535		case 1:
 536			printk(" %02X", host->status[target][ptr].ssr);
 537			break;
 538
 539		case 2:
 540			time_diff = host->status[target][ptr].when - prev;
 541			prev = host->status[target][ptr].when;
 542			if (time_diff == 0)
 543				printk("==^");
 544			else if (time_diff >= 100)
 545				printk("   ");
 546			else
 547				printk(" %02ld", time_diff);
 548			break;
 549		}
 550	}
 551
 552	printk("\n");
 553}
 554
 555static
 556void acornscsi_dumplog(AS_Host *host, int target)
 557{
 558    do {
 559	acornscsi_dumplogline(host, target, 0);
 560	acornscsi_dumplogline(host, target, 1);
 561	acornscsi_dumplogline(host, target, 2);
 562
 563	if (target == 8)
 564	    break;
 565
 566	target = 8;
 567    } while (1);
 568}
 569
 570static
 571char acornscsi_target(AS_Host *host)
 572{
 573	if (host->SCpnt)
 574		return '0' + host->SCpnt->device->id;
 575	return 'H';
 576}
 577
 578/*
 579 * Prototype: cmdtype_t acornscsi_cmdtype(int command)
 580 * Purpose  : differentiate READ from WRITE from other commands
 581 * Params   : command - command to interpret
 582 * Returns  : CMD_READ	- command reads data,
 583 *	      CMD_WRITE - command writes data,
 584 *	      CMD_MISC	- everything else
 585 */
 586static inline
 587cmdtype_t acornscsi_cmdtype(int command)
 588{
 589    switch (command) {
 590    case WRITE_6:  case WRITE_10:  case WRITE_12:
 591	return CMD_WRITE;
 592    case READ_6:   case READ_10:   case READ_12:
 593	return CMD_READ;
 594    default:
 595	return CMD_MISC;
 596    }
 597}
 598
 599/*
 600 * Prototype: int acornscsi_datadirection(int command)
 601 * Purpose  : differentiate between commands that have a DATA IN phase
 602 *	      and a DATA OUT phase
 603 * Params   : command - command to interpret
 604 * Returns  : DATADIR_OUT - data out phase expected
 605 *	      DATADIR_IN  - data in phase expected
 606 */
 607static
 608datadir_t acornscsi_datadirection(int command)
 609{
 610    switch (command) {
 611    case CHANGE_DEFINITION:	case COMPARE:		case COPY:
 612    case COPY_VERIFY:		case LOG_SELECT:	case MODE_SELECT:
 613    case MODE_SELECT_10:	case SEND_DIAGNOSTIC:	case WRITE_BUFFER:
 614    case FORMAT_UNIT:		case REASSIGN_BLOCKS:	case RESERVE:
 615    case SEARCH_EQUAL:		case SEARCH_HIGH:	case SEARCH_LOW:
 616    case WRITE_6:		case WRITE_10:		case WRITE_VERIFY:
 617    case UPDATE_BLOCK:		case WRITE_LONG:	case WRITE_SAME:
 618    case SEARCH_HIGH_12:	case SEARCH_EQUAL_12:	case SEARCH_LOW_12:
 619    case WRITE_12:		case WRITE_VERIFY_12:	case SET_WINDOW:
 620    case MEDIUM_SCAN:		case SEND_VOLUME_TAG:	case 0xea:
 621	return DATADIR_OUT;
 622    default:
 623	return DATADIR_IN;
 624    }
 625}
 626
 627/*
 628 * Purpose  : provide values for synchronous transfers with 33C93.
 629 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 630 *	Modified by Russell King for 8MHz WD33C93A
 631 */
 632static struct sync_xfer_tbl {
 633    unsigned int period_ns;
 634    unsigned char reg_value;
 635} sync_xfer_table[] = {
 636    {	1, 0x20 },    { 249, 0x20 },	{ 374, 0x30 },
 637    { 499, 0x40 },    { 624, 0x50 },	{ 749, 0x60 },
 638    { 874, 0x70 },    { 999, 0x00 },	{   0,	  0 }
 639};
 640
 641/*
 642 * Prototype: int acornscsi_getperiod(unsigned char syncxfer)
 643 * Purpose  : period for the synchronous transfer setting
 644 * Params   : syncxfer SYNCXFER register value
 645 * Returns  : period in ns.
 646 */
 647static
 648int acornscsi_getperiod(unsigned char syncxfer)
 649{
 650    int i;
 651
 652    syncxfer &= 0xf0;
 653    if (syncxfer == 0x10)
 654	syncxfer = 0;
 655
 656    for (i = 1; sync_xfer_table[i].period_ns; i++)
 657	if (syncxfer == sync_xfer_table[i].reg_value)
 658	    return sync_xfer_table[i].period_ns;
 659    return 0;
 660}
 661
 662/*
 663 * Prototype: int round_period(unsigned int period)
 664 * Purpose  : return index into above table for a required REQ period
 665 * Params   : period - time (ns) for REQ
 666 * Returns  : table index
 667 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 668 */
 669static inline
 670int round_period(unsigned int period)
 671{
 672    int i;
 673
 674    for (i = 1; sync_xfer_table[i].period_ns; i++) {
 675	if ((period <= sync_xfer_table[i].period_ns) &&
 676	    (period > sync_xfer_table[i - 1].period_ns))
 677	    return i;
 678    }
 679    return 7;
 680}
 681
 682/*
 683 * Prototype: unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
 684 * Purpose  : calculate value for 33c93s SYNC register
 685 * Params   : period - time (ns) for REQ
 686 *	      offset - offset in bytes between REQ/ACK
 687 * Returns  : value for SYNC register
 688 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 689 */
 690static
 691unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
 692{
 693    return sync_xfer_table[round_period(period)].reg_value |
 694		((offset < SDTR_SIZE) ? offset : SDTR_SIZE);
 695}
 696
 697/* ====================================================================================
 698 * Command functions
 699 */
 700/*
 701 * Function: acornscsi_kick(AS_Host *host)
 702 * Purpose : kick next command to interface
 703 * Params  : host - host to send command to
 704 * Returns : INTR_IDLE if idle, otherwise INTR_PROCESSING
 705 * Notes   : interrupts are always disabled!
 706 */
 707static
 708intr_ret_t acornscsi_kick(AS_Host *host)
 709{
 710    int from_queue = 0;
 711    struct scsi_cmnd *SCpnt;
 712
 713    /* first check to see if a command is waiting to be executed */
 714    SCpnt = host->origSCpnt;
 715    host->origSCpnt = NULL;
 716
 717    /* retrieve next command */
 718    if (!SCpnt) {
 719	SCpnt = queue_remove_exclude(&host->queues.issue, host->busyluns);
 720	if (!SCpnt)
 721	    return INTR_IDLE;
 722
 723	from_queue = 1;
 724    }
 725
 726    if (host->scsi.disconnectable && host->SCpnt) {
 727	queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
 728	host->scsi.disconnectable = 0;
 729#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
 730	DBG(host->SCpnt, printk("scsi%d.%c: moved command to disconnected queue\n",
 731		host->host->host_no, acornscsi_target(host)));
 732#endif
 733	host->SCpnt = NULL;
 734    }
 735
 736    /*
 737     * If we have an interrupt pending, then we may have been reselected.
 738     * In this case, we don't want to write to the registers
 739     */
 740    if (!(sbic_arm_read(host, SBIC_ASR) & (ASR_INT|ASR_BSY|ASR_CIP))) {
 741	sbic_arm_write(host, SBIC_DESTID, SCpnt->device->id);
 742	sbic_arm_write(host, SBIC_CMND, CMND_SELWITHATN);
 743    }
 744
 745    /*
 746     * claim host busy - all of these must happen atomically wrt
 747     * our interrupt routine.  Failure means command loss.
 748     */
 749    host->scsi.phase = PHASE_CONNECTING;
 750    host->SCpnt = SCpnt;
 751    host->scsi.SCp = SCpnt->SCp;
 752    host->dma.xfer_setup = 0;
 753    host->dma.xfer_required = 0;
 754    host->dma.xfer_done = 0;
 755
 756#if (DEBUG & (DEBUG_ABORT|DEBUG_CONNECT))
 757    DBG(SCpnt,printk("scsi%d.%c: starting cmd %02X\n",
 758	    host->host->host_no, '0' + SCpnt->device->id,
 759	    SCpnt->cmnd[0]));
 760#endif
 761
 762    if (from_queue) {
 763#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
 764	/*
 765	 * tagged queueing - allocate a new tag to this command
 766	 */
 767	if (SCpnt->device->simple_tags) {
 768	    SCpnt->device->current_tag += 1;
 769	    if (SCpnt->device->current_tag == 0)
 770		SCpnt->device->current_tag = 1;
 771	    SCpnt->tag = SCpnt->device->current_tag;
 772	} else
 773#endif
 774	    set_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
 775
 776	host->stats.removes += 1;
 777
 778	switch (acornscsi_cmdtype(SCpnt->cmnd[0])) {
 779	case CMD_WRITE:
 780	    host->stats.writes += 1;
 781	    break;
 782	case CMD_READ:
 783	    host->stats.reads += 1;
 784	    break;
 785	case CMD_MISC:
 786	    host->stats.miscs += 1;
 787	    break;
 788	}
 789    }
 790
 791    return INTR_PROCESSING;
 792}    
 793
 794/*
 795 * Function: void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp, unsigned int result)
 796 * Purpose : complete processing for command
 797 * Params  : host   - interface that completed
 798 *	     result - driver byte of result
 799 */
 800static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
 801			   unsigned int result)
 802{
 803	struct scsi_cmnd *SCpnt = *SCpntp;
 804
 805    /* clean up */
 806    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
 807
 808    host->stats.fins += 1;
 809
 810    if (SCpnt) {
 811	*SCpntp = NULL;
 812
 813	acornscsi_dma_cleanup(host);
 814
 815	SCpnt->result = result << 16 | host->scsi.SCp.Message << 8 | host->scsi.SCp.Status;
 816
 817	/*
 818	 * In theory, this should not happen.  In practice, it seems to.
 819	 * Only trigger an error if the device attempts to report all happy
 820	 * but with untransferred buffers...  If we don't do something, then
 821	 * data loss will occur.  Should we check SCpnt->underflow here?
 822	 * It doesn't appear to be set to something meaningful by the higher
 823	 * levels all the time.
 824	 */
 825	if (result == DID_OK) {
 826		int xfer_warn = 0;
 827
 828		if (SCpnt->underflow == 0) {
 829			if (host->scsi.SCp.ptr &&
 830			    acornscsi_cmdtype(SCpnt->cmnd[0]) != CMD_MISC)
 831				xfer_warn = 1;
 832		} else {
 833			if (host->scsi.SCp.scsi_xferred < SCpnt->underflow ||
 834			    host->scsi.SCp.scsi_xferred != host->dma.transferred)
 835				xfer_warn = 1;
 836		}
 837
 838		/* ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.6)
 839		 *  Targets which break data transfers into multiple
 840		 *  connections shall end each successful connection
 841		 *  (except possibly the last) with a SAVE DATA
 842		 *  POINTER - DISCONNECT message sequence.
 843		 *
 844		 * This makes it difficult to ensure that a transfer has
 845		 * completed.  If we reach the end of a transfer during
 846		 * the command, then we can only have finished the transfer.
 847		 * therefore, if we seem to have some data remaining, this
 848		 * is not a problem.
 849		 */
 850		if (host->dma.xfer_done)
 851			xfer_warn = 0;
 852
 853		if (xfer_warn) {
 854		    switch (status_byte(SCpnt->result)) {
 855		    case CHECK_CONDITION:
 856		    case COMMAND_TERMINATED:
 857		    case BUSY:
 858		    case QUEUE_FULL:
 859		    case RESERVATION_CONFLICT:
 860			break;
 861
 862		    default:
 863			printk(KERN_ERR "scsi%d.H: incomplete data transfer detected: result=%08X command=",
 864				host->host->host_no, SCpnt->result);
 865			__scsi_print_command(SCpnt->cmnd);
 866			acornscsi_dumpdma(host, "done");
 867		 	acornscsi_dumplog(host, SCpnt->device->id);
 868			SCpnt->result &= 0xffff;
 869			SCpnt->result |= DID_ERROR << 16;
 870		    }
 871		}
 872	}
 873
 874	if (!SCpnt->scsi_done)
 875	    panic("scsi%d.H: null scsi_done function in acornscsi_done", host->host->host_no);
 876
 877	clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
 878
 879	SCpnt->scsi_done(SCpnt);
 880    } else
 881	printk("scsi%d: null command in acornscsi_done", host->host->host_no);
 882
 883    host->scsi.phase = PHASE_IDLE;
 884}
 885
 886/* ====================================================================================
 887 * DMA routines
 888 */
 889/*
 890 * Purpose  : update SCSI Data Pointer
 891 * Notes    : this will only be one SG entry or less
 892 */
 893static
 894void acornscsi_data_updateptr(AS_Host *host, struct scsi_pointer *SCp, unsigned int length)
 895{
 896    SCp->ptr += length;
 897    SCp->this_residual -= length;
 898
 899    if (SCp->this_residual == 0 && next_SCp(SCp) == 0)
 900	host->dma.xfer_done = 1;
 901}
 902
 903/*
 904 * Prototype: void acornscsi_data_read(AS_Host *host, char *ptr,
 905 *				unsigned int start_addr, unsigned int length)
 906 * Purpose  : read data from DMA RAM
 907 * Params   : host - host to transfer from
 908 *	      ptr  - DRAM address
 909 *	      start_addr - host mem address
 910 *	      length - number of bytes to transfer
 911 * Notes    : this will only be one SG entry or less
 912 */
 913static
 914void acornscsi_data_read(AS_Host *host, char *ptr,
 915				 unsigned int start_addr, unsigned int length)
 916{
 917    extern void __acornscsi_in(void __iomem *, char *buf, int len);
 918    unsigned int page, offset, len = length;
 919
 920    page = (start_addr >> 12);
 921    offset = start_addr & ((1 << 12) - 1);
 922
 923    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 924
 925    while (len > 0) {
 926	unsigned int this_len;
 927
 928	if (len + offset > (1 << 12))
 929	    this_len = (1 << 12) - offset;
 930	else
 931	    this_len = len;
 932
 933	__acornscsi_in(host->base + (offset << 1), ptr, this_len);
 934
 935	offset += this_len;
 936	ptr += this_len;
 937	len -= this_len;
 938
 939	if (offset == (1 << 12)) {
 940	    offset = 0;
 941	    page ++;
 942	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 943	}
 944    }
 945    writeb(host->card.page_reg, host->fast + PAGE_REG);
 946}
 947
 948/*
 949 * Prototype: void acornscsi_data_write(AS_Host *host, char *ptr,
 950 *				unsigned int start_addr, unsigned int length)
 951 * Purpose  : write data to DMA RAM
 952 * Params   : host - host to transfer from
 953 *	      ptr  - DRAM address
 954 *	      start_addr - host mem address
 955 *	      length - number of bytes to transfer
 956 * Notes    : this will only be one SG entry or less
 957 */
 958static
 959void acornscsi_data_write(AS_Host *host, char *ptr,
 960				 unsigned int start_addr, unsigned int length)
 961{
 962    extern void __acornscsi_out(void __iomem *, char *buf, int len);
 963    unsigned int page, offset, len = length;
 964
 965    page = (start_addr >> 12);
 966    offset = start_addr & ((1 << 12) - 1);
 967
 968    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 969
 970    while (len > 0) {
 971	unsigned int this_len;
 972
 973	if (len + offset > (1 << 12))
 974	    this_len = (1 << 12) - offset;
 975	else
 976	    this_len = len;
 977
 978	__acornscsi_out(host->base + (offset << 1), ptr, this_len);
 979
 980	offset += this_len;
 981	ptr += this_len;
 982	len -= this_len;
 983
 984	if (offset == (1 << 12)) {
 985	    offset = 0;
 986	    page ++;
 987	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
 988	}
 989    }
 990    writeb(host->card.page_reg, host->fast + PAGE_REG);
 991}
 992
 993/* =========================================================================================
 994 * On-board DMA routines
 995 */
 996#ifdef USE_DMAC
 997/*
 998 * Prototype: void acornscsi_dmastop(AS_Host *host)
 999 * Purpose  : stop all DMA
1000 * Params   : host - host on which to stop DMA
1001 * Notes    : This is called when leaving DATA IN/OUT phase,
1002 *	      or when interface is RESET
1003 */
1004static inline
1005void acornscsi_dma_stop(AS_Host *host)
1006{
1007    dmac_write(host, DMAC_MASKREG, MASK_ON);
1008    dmac_clearintr(host);
1009
1010#if (DEBUG & DEBUG_DMA)
1011    DBG(host->SCpnt, acornscsi_dumpdma(host, "stop"));
1012#endif
1013}
1014
1015/*
1016 * Function: void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1017 * Purpose : setup DMA controller for data transfer
1018 * Params  : host - host to setup
1019 *	     direction - data transfer direction
1020 * Notes   : This is called when entering DATA I/O phase, not
1021 *	     while we're in a DATA I/O phase
1022 */
1023static
1024void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1025{
1026    unsigned int address, length, mode;
1027
1028    host->dma.direction = direction;
1029
1030    dmac_write(host, DMAC_MASKREG, MASK_ON);
1031
1032    if (direction == DMA_OUT) {
1033#if (DEBUG & DEBUG_NO_WRITE)
1034	if (NO_WRITE & (1 << host->SCpnt->device->id)) {
1035	    printk(KERN_CRIT "scsi%d.%c: I can't handle DMA_OUT!\n",
1036		    host->host->host_no, acornscsi_target(host));
1037	    return;
1038	}
1039#endif
1040	mode = DMAC_WRITE;
1041    } else
1042	mode = DMAC_READ;
1043
1044    /*
1045     * Allocate some buffer space, limited to half the buffer size
1046     */
1047    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1048    if (length) {
1049	host->dma.start_addr = address = host->dma.free_addr;
1050	host->dma.free_addr = (host->dma.free_addr + length) &
1051				(DMAC_BUFFER_SIZE - 1);
1052
1053	/*
1054	 * Transfer data to DMA memory
1055	 */
1056	if (direction == DMA_OUT)
1057	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1058				length);
1059
1060	length -= 1;
1061	dmac_write(host, DMAC_TXCNTLO, length);
1062	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1063	dmac_write(host, DMAC_TXADRLO, address);
1064	dmac_write(host, DMAC_TXADRMD, address >> 8);
1065	dmac_write(host, DMAC_TXADRHI, 0);
1066	dmac_write(host, DMAC_MODECON, mode);
1067	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1068
1069#if (DEBUG & DEBUG_DMA)
1070	DBG(host->SCpnt, acornscsi_dumpdma(host, "strt"));
1071#endif
1072	host->dma.xfer_setup = 1;
1073    }
1074}
1075
1076/*
1077 * Function: void acornscsi_dma_cleanup(AS_Host *host)
1078 * Purpose : ensure that all DMA transfers are up-to-date & host->scsi.SCp is correct
1079 * Params  : host - host to finish
1080 * Notes   : This is called when a command is:
1081 *		terminating, RESTORE_POINTERS, SAVE_POINTERS, DISCONECT
1082 *	   : This must not return until all transfers are completed.
1083 */
1084static
1085void acornscsi_dma_cleanup(AS_Host *host)
1086{
1087    dmac_write(host, DMAC_MASKREG, MASK_ON);
1088    dmac_clearintr(host);
1089
1090    /*
1091     * Check for a pending transfer
1092     */
1093    if (host->dma.xfer_required) {
1094	host->dma.xfer_required = 0;
1095	if (host->dma.direction == DMA_IN)
1096	    acornscsi_data_read(host, host->dma.xfer_ptr,
1097				 host->dma.xfer_start, host->dma.xfer_length);
1098    }
1099
1100    /*
1101     * Has a transfer been setup?
1102     */
1103    if (host->dma.xfer_setup) {
1104	unsigned int transferred;
1105
1106	host->dma.xfer_setup = 0;
1107
1108#if (DEBUG & DEBUG_DMA)
1109	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupi"));
1110#endif
1111
1112	/*
1113	 * Calculate number of bytes transferred from DMA.
1114	 */
1115	transferred = dmac_address(host) - host->dma.start_addr;
1116	host->dma.transferred += transferred;
1117
1118	if (host->dma.direction == DMA_IN)
1119	    acornscsi_data_read(host, host->scsi.SCp.ptr,
1120				 host->dma.start_addr, transferred);
1121
1122	/*
1123	 * Update SCSI pointers
1124	 */
1125	acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1126#if (DEBUG & DEBUG_DMA)
1127	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupo"));
1128#endif
1129    }
1130}
1131
1132/*
1133 * Function: void acornscsi_dmacintr(AS_Host *host)
1134 * Purpose : handle interrupts from DMAC device
1135 * Params  : host - host to process
1136 * Notes   : If reading, we schedule the read to main memory &
1137 *	     allow the transfer to continue.
1138 *	   : If writing, we fill the onboard DMA memory from main
1139 *	     memory.
1140 *	   : Called whenever DMAC finished it's current transfer.
1141 */
1142static
1143void acornscsi_dma_intr(AS_Host *host)
1144{
1145    unsigned int address, length, transferred;
1146
1147#if (DEBUG & DEBUG_DMA)
1148    DBG(host->SCpnt, acornscsi_dumpdma(host, "inti"));
1149#endif
1150
1151    dmac_write(host, DMAC_MASKREG, MASK_ON);
1152    dmac_clearintr(host);
1153
1154    /*
1155     * Calculate amount transferred via DMA
1156     */
1157    transferred = dmac_address(host) - host->dma.start_addr;
1158    host->dma.transferred += transferred;
1159
1160    /*
1161     * Schedule DMA transfer off board
1162     */
1163    if (host->dma.direction == DMA_IN) {
1164	host->dma.xfer_start = host->dma.start_addr;
1165	host->dma.xfer_length = transferred;
1166	host->dma.xfer_ptr = host->scsi.SCp.ptr;
1167	host->dma.xfer_required = 1;
1168    }
1169
1170    acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1171
1172    /*
1173     * Allocate some buffer space, limited to half the on-board RAM size
1174     */
1175    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1176    if (length) {
1177	host->dma.start_addr = address = host->dma.free_addr;
1178	host->dma.free_addr = (host->dma.free_addr + length) &
1179				(DMAC_BUFFER_SIZE - 1);
1180
1181	/*
1182	 * Transfer data to DMA memory
1183	 */
1184	if (host->dma.direction == DMA_OUT)
1185	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1186				length);
1187
1188	length -= 1;
1189	dmac_write(host, DMAC_TXCNTLO, length);
1190	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1191	dmac_write(host, DMAC_TXADRLO, address);
1192	dmac_write(host, DMAC_TXADRMD, address >> 8);
1193	dmac_write(host, DMAC_TXADRHI, 0);
1194	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1195
1196#if (DEBUG & DEBUG_DMA)
1197	DBG(host->SCpnt, acornscsi_dumpdma(host, "into"));
1198#endif
1199    } else {
1200	host->dma.xfer_setup = 0;
1201#if 0
1202	/*
1203	 * If the interface still wants more, then this is an error.
1204	 * We give it another byte, but we also attempt to raise an
1205	 * attention condition.  We continue giving one byte until
1206	 * the device recognises the attention.
1207	 */
1208	if (dmac_read(host, DMAC_STATUS) & STATUS_RQ0) {
1209	    acornscsi_abortcmd(host, host->SCpnt->tag);
1210
1211	    dmac_write(host, DMAC_TXCNTLO, 0);
1212	    dmac_write(host, DMAC_TXCNTHI, 0);
1213	    dmac_write(host, DMAC_TXADRLO, 0);
1214	    dmac_write(host, DMAC_TXADRMD, 0);
1215	    dmac_write(host, DMAC_TXADRHI, 0);
1216	    dmac_write(host, DMAC_MASKREG, MASK_OFF);
1217	}
1218#endif
1219    }
1220}
1221
1222/*
1223 * Function: void acornscsi_dma_xfer(AS_Host *host)
1224 * Purpose : transfer data between AcornSCSI and memory
1225 * Params  : host - host to process
1226 */
1227static
1228void acornscsi_dma_xfer(AS_Host *host)
1229{
1230    host->dma.xfer_required = 0;
1231
1232    if (host->dma.direction == DMA_IN)
1233	acornscsi_data_read(host, host->dma.xfer_ptr,
1234				host->dma.xfer_start, host->dma.xfer_length);
1235}
1236
1237/*
1238 * Function: void acornscsi_dma_adjust(AS_Host *host)
1239 * Purpose : adjust DMA pointers & count for bytes transferred to
1240 *	     SBIC but not SCSI bus.
1241 * Params  : host - host to adjust DMA count for
1242 */
1243static
1244void acornscsi_dma_adjust(AS_Host *host)
1245{
1246    if (host->dma.xfer_setup) {
1247	signed long transferred;
1248#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1249	DBG(host->SCpnt, acornscsi_dumpdma(host, "adji"));
1250#endif
1251	/*
1252	 * Calculate correct DMA address - DMA is ahead of SCSI bus while
1253	 * writing.
1254	 *  host->scsi.SCp.scsi_xferred is the number of bytes
1255	 *  actually transferred to/from the SCSI bus.
1256	 *  host->dma.transferred is the number of bytes transferred
1257	 *  over DMA since host->dma.start_addr was last set.
1258	 *
1259	 * real_dma_addr = host->dma.start_addr + host->scsi.SCp.scsi_xferred
1260	 *		   - host->dma.transferred
1261	 */
1262	transferred = host->scsi.SCp.scsi_xferred - host->dma.transferred;
1263	if (transferred < 0)
1264	    printk("scsi%d.%c: Ack! DMA write correction %ld < 0!\n",
1265		    host->host->host_no, acornscsi_target(host), transferred);
1266	else if (transferred == 0)
1267	    host->dma.xfer_setup = 0;
1268	else {
1269	    transferred += host->dma.start_addr;
1270	    dmac_write(host, DMAC_TXADRLO, transferred);
1271	    dmac_write(host, DMAC_TXADRMD, transferred >> 8);
1272	    dmac_write(host, DMAC_TXADRHI, transferred >> 16);
1273#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1274	    DBG(host->SCpnt, acornscsi_dumpdma(host, "adjo"));
1275#endif
1276	}
1277    }
1278}
1279#endif
1280
1281/* =========================================================================================
1282 * Data I/O
1283 */
1284static int
1285acornscsi_write_pio(AS_Host *host, char *bytes, int *ptr, int len, unsigned int max_timeout)
1286{
1287	unsigned int asr, timeout = max_timeout;
1288	int my_ptr = *ptr;
1289
1290	while (my_ptr < len) {
1291		asr = sbic_arm_read(host, SBIC_ASR);
1292
1293		if (asr & ASR_DBR) {
1294			timeout = max_timeout;
1295
1296			sbic_arm_write(host, SBIC_DATA, bytes[my_ptr++]);
1297		} else if (asr & ASR_INT)
1298			break;
1299		else if (--timeout == 0)
1300			break;
1301		udelay(1);
1302	}
1303
1304	*ptr = my_ptr;
1305
1306	return (timeout == 0) ? -1 : 0;
1307}
1308
1309/*
1310 * Function: void acornscsi_sendcommand(AS_Host *host)
1311 * Purpose : send a command to a target
1312 * Params  : host - host which is connected to target
1313 */
1314static void
1315acornscsi_sendcommand(AS_Host *host)
1316{
1317	struct scsi_cmnd *SCpnt = host->SCpnt;
1318
1319    sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1320    sbic_arm_writenext(host, 0);
1321    sbic_arm_writenext(host, SCpnt->cmd_len - host->scsi.SCp.sent_command);
1322
1323    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1324
1325    if (acornscsi_write_pio(host, SCpnt->cmnd,
1326	(int *)&host->scsi.SCp.sent_command, SCpnt->cmd_len, 1000000))
1327	printk("scsi%d: timeout while sending command\n", host->host->host_no);
1328
1329    host->scsi.phase = PHASE_COMMAND;
1330}
1331
1332static
1333void acornscsi_sendmessage(AS_Host *host)
1334{
1335    unsigned int message_length = msgqueue_msglength(&host->scsi.msgs);
1336    unsigned int msgnr;
1337    struct message *msg;
1338
1339#if (DEBUG & DEBUG_MESSAGES)
1340    printk("scsi%d.%c: sending message ",
1341	    host->host->host_no, acornscsi_target(host));
1342#endif
1343
1344    switch (message_length) {
1345    case 0:
1346	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1347
1348	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 1");
1349
1350	sbic_arm_write(host, SBIC_DATA, NOP);
1351
1352	host->scsi.last_message = NOP;
1353#if (DEBUG & DEBUG_MESSAGES)
1354	printk("NOP");
1355#endif
1356	break;
1357
1358    case 1:
1359	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1360	msg = msgqueue_getmsg(&host->scsi.msgs, 0);
1361
1362	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 2");
1363
1364	sbic_arm_write(host, SBIC_DATA, msg->msg[0]);
1365
1366	host->scsi.last_message = msg->msg[0];
1367#if (DEBUG & DEBUG_MESSAGES)
1368	spi_print_msg(msg->msg);
1369#endif
1370	break;
1371
1372    default:
1373	/*
1374	 * ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.14)
1375	 * 'When a target sends this (MESSAGE_REJECT) message, it
1376	 *  shall change to MESSAGE IN phase and send this message
1377	 *  prior to requesting additional message bytes from the
1378	 *  initiator.  This provides an interlock so that the
1379	 *  initiator can determine which message byte is rejected.
1380	 */
1381	sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1382	sbic_arm_writenext(host, 0);
1383	sbic_arm_writenext(host, message_length);
1384	acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1385
1386	msgnr = 0;
1387	while ((msg = msgqueue_getmsg(&host->scsi.msgs, msgnr++)) != NULL) {
1388	    unsigned int i;
1389#if (DEBUG & DEBUG_MESSAGES)
1390	    spi_print_msg(msg);
1391#endif
1392	    i = 0;
1393	    if (acornscsi_write_pio(host, msg->msg, &i, msg->length, 1000000))
1394		printk("scsi%d: timeout while sending message\n", host->host->host_no);
1395
1396	    host->scsi.last_message = msg->msg[0];
1397	    if (msg->msg[0] == EXTENDED_MESSAGE)
1398		host->scsi.last_message |= msg->msg[2] << 8;
1399
1400	    if (i != msg->length)
1401		break;
1402	}
1403	break;
1404    }
1405#if (DEBUG & DEBUG_MESSAGES)
1406    printk("\n");
1407#endif
1408}
1409
1410/*
1411 * Function: void acornscsi_readstatusbyte(AS_Host *host)
1412 * Purpose : Read status byte from connected target
1413 * Params  : host - host connected to target
1414 */
1415static
1416void acornscsi_readstatusbyte(AS_Host *host)
1417{
1418    acornscsi_sbic_issuecmd(host, CMND_XFERINFO|CMND_SBT);
1419    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "reading status byte");
1420    host->scsi.SCp.Status = sbic_arm_read(host, SBIC_DATA);
1421}
1422
1423/*
1424 * Function: unsigned char acornscsi_readmessagebyte(AS_Host *host)
1425 * Purpose : Read one message byte from connected target
1426 * Params  : host - host connected to target
1427 */
1428static
1429unsigned char acornscsi_readmessagebyte(AS_Host *host)
1430{
1431    unsigned char message;
1432
1433    acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1434
1435    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "for message byte");
1436
1437    message = sbic_arm_read(host, SBIC_DATA);
1438
1439    /* wait for MSGIN-XFER-PAUSED */
1440    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after message byte");
1441
1442    sbic_arm_read(host, SBIC_SSR);
1443
1444    return message;
1445}
1446
1447/*
1448 * Function: void acornscsi_message(AS_Host *host)
1449 * Purpose : Read complete message from connected target & action message
1450 * Params  : host - host connected to target
1451 */
1452static
1453void acornscsi_message(AS_Host *host)
1454{
1455    unsigned char message[16];
1456    unsigned int msgidx = 0, msglen = 1;
1457
1458    do {
1459	message[msgidx] = acornscsi_readmessagebyte(host);
1460
1461	switch (msgidx) {
1462	case 0:
1463	    if (message[0] == EXTENDED_MESSAGE ||
1464		(message[0] >= 0x20 && message[0] <= 0x2f))
1465		msglen = 2;
1466	    break;
1467
1468	case 1:
1469	    if (message[0] == EXTENDED_MESSAGE)
1470		msglen += message[msgidx];
1471	    break;
1472	}
1473	msgidx += 1;
1474	if (msgidx < msglen) {
1475	    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1476
1477	    /* wait for next msg-in */
1478	    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after negate ack");
1479	    sbic_arm_read(host, SBIC_SSR);
1480	}
1481    } while (msgidx < msglen);
1482
1483#if (DEBUG & DEBUG_MESSAGES)
1484    printk("scsi%d.%c: message in: ",
1485	    host->host->host_no, acornscsi_target(host));
1486    spi_print_msg(message);
1487    printk("\n");
1488#endif
1489
1490    if (host->scsi.phase == PHASE_RECONNECTED) {
1491	/*
1492	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1493	 * 'Whenever a target reconnects to an initiator to continue
1494	 *  a tagged I/O process, the SIMPLE QUEUE TAG message shall
1495	 *  be sent immediately following the IDENTIFY message...'
1496	 */
1497	if (message[0] == SIMPLE_QUEUE_TAG)
1498	    host->scsi.reconnected.tag = message[1];
1499	if (acornscsi_reconnect_finish(host))
1500	    host->scsi.phase = PHASE_MSGIN;
1501    }
1502
1503    switch (message[0]) {
1504    case ABORT:
1505    case ABORT_TAG:
1506    case COMMAND_COMPLETE:
1507	if (host->scsi.phase != PHASE_STATUSIN) {
1508	    printk(KERN_ERR "scsi%d.%c: command complete following non-status in phase?\n",
1509		    host->host->host_no, acornscsi_target(host));
1510	    acornscsi_dumplog(host, host->SCpnt->device->id);
1511	}
1512	host->scsi.phase = PHASE_DONE;
1513	host->scsi.SCp.Message = message[0];
1514	break;
1515
1516    case SAVE_POINTERS:
1517	/*
1518	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.20)
1519	 * 'The SAVE DATA POINTER message is sent from a target to
1520	 *  direct the initiator to copy the active data pointer to
1521	 *  the saved data pointer for the current I/O process.
1522	 */
1523	acornscsi_dma_cleanup(host);
1524	host->SCpnt->SCp = host->scsi.SCp;
1525	host->SCpnt->SCp.sent_command = 0;
1526	host->scsi.phase = PHASE_MSGIN;
1527	break;
1528
1529    case RESTORE_POINTERS:
1530	/*
1531	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.19)
1532	 * 'The RESTORE POINTERS message is sent from a target to
1533	 *  direct the initiator to copy the most recently saved
1534	 *  command, data, and status pointers for the I/O process
1535	 *  to the corresponding active pointers.  The command and
1536	 *  status pointers shall be restored to the beginning of
1537	 *  the present command and status areas.'
1538	 */
1539	acornscsi_dma_cleanup(host);
1540	host->scsi.SCp = host->SCpnt->SCp;
1541	host->scsi.phase = PHASE_MSGIN;
1542	break;
1543
1544    case DISCONNECT:
1545	/*
1546	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 6.4.2)
1547	 * 'On those occasions when an error or exception condition occurs
1548	 *  and the target elects to repeat the information transfer, the
1549	 *  target may repeat the transfer either issuing a RESTORE POINTERS
1550	 *  message or by disconnecting without issuing a SAVE POINTERS
1551	 *  message.  When reconnection is completed, the most recent
1552	 *  saved pointer values are restored.'
1553	 */
1554	acornscsi_dma_cleanup(host);
1555	host->scsi.phase = PHASE_DISCONNECT;
1556	break;
1557
1558    case MESSAGE_REJECT:
1559#if 0 /* this isn't needed any more */
1560	/*
1561	 * If we were negociating sync transfer, we don't yet know if
1562	 * this REJECT is for the sync transfer or for the tagged queue/wide
1563	 * transfer.  Re-initiate sync transfer negotiation now, and if
1564	 * we got a REJECT in response to SDTR, then it'll be set to DONE.
1565	 */
1566	if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST)
1567	    host->device[host->SCpnt->device->id].sync_state = SYNC_NEGOCIATE;
1568#endif
1569
1570	/*
1571	 * If we have any messages waiting to go out, then assert ATN now
1572	 */
1573	if (msgqueue_msglength(&host->scsi.msgs))
1574	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1575
1576	switch (host->scsi.last_message) {
1577#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1578	case HEAD_OF_QUEUE_TAG:
1579	case ORDERED_QUEUE_TAG:
1580	case SIMPLE_QUEUE_TAG:
1581	    /*
1582	     * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1583	     *  If a target does not implement tagged queuing and a queue tag
1584	     *  message is received, it shall respond with a MESSAGE REJECT
1585	     *  message and accept the I/O process as if it were untagged.
1586	     */
1587	    printk(KERN_NOTICE "scsi%d.%c: disabling tagged queueing\n",
1588		    host->host->host_no, acornscsi_target(host));
1589	    host->SCpnt->device->simple_tags = 0;
1590	    set_bit(host->SCpnt->device->id * 8 + host->SCpnt->device->lun, host->busyluns);
1591	    break;
1592#endif
1593	case EXTENDED_MESSAGE | (EXTENDED_SDTR << 8):
1594	    /*
1595	     * Target can't handle synchronous transfers
1596	     */
1597	    printk(KERN_NOTICE "scsi%d.%c: Using asynchronous transfer\n",
1598		    host->host->host_no, acornscsi_target(host));
1599	    host->device[host->SCpnt->device->id].sync_xfer = SYNCHTRANSFER_2DBA;
1600	    host->device[host->SCpnt->device->id].sync_state = SYNC_ASYNCHRONOUS;
1601	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1602	    break;
1603
1604	default:
1605	    break;
1606	}
1607	break;
1608
1609    case QUEUE_FULL:
1610	/* TODO: target queue is full */
1611	break;
1612
1613    case SIMPLE_QUEUE_TAG:
1614	/* tag queue reconnect... message[1] = queue tag.  Print something to indicate something happened! */
1615	printk("scsi%d.%c: reconnect queue tag %02X\n",
1616		host->host->host_no, acornscsi_target(host),
1617		message[1]);
1618	break;
1619
1620    case EXTENDED_MESSAGE:
1621	switch (message[2]) {
1622#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1623	case EXTENDED_SDTR:
1624	    if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST) {
1625		/*
1626		 * We requested synchronous transfers.  This isn't quite right...
1627		 * We can only say if this succeeded if we proceed on to execute the
1628		 * command from this message.  If we get a MESSAGE PARITY ERROR,
1629		 * and the target retries fail, then we fallback to asynchronous mode
1630		 */
1631		host->device[host->SCpnt->device->id].sync_state = SYNC_COMPLETED;
1632		printk(KERN_NOTICE "scsi%d.%c: Using synchronous transfer, offset %d, %d ns\n",
1633			host->host->host_no, acornscsi_target(host),
1634			message[4], message[3] * 4);
1635		host->device[host->SCpnt->device->id].sync_xfer =
1636			calc_sync_xfer(message[3] * 4, message[4]);
1637	    } else {
1638		unsigned char period, length;
1639		/*
1640		 * Target requested synchronous transfers.  The agreement is only
1641		 * to be in operation AFTER the target leaves message out phase.
1642		 */
1643		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1644		period = max_t(unsigned int, message[3], sdtr_period / 4);
1645		length = min_t(unsigned int, message[4], sdtr_size);
1646		msgqueue_addmsg(&host->scsi.msgs, 5, EXTENDED_MESSAGE, 3,
1647				 EXTENDED_SDTR, period, length);
1648		host->device[host->SCpnt->device->id].sync_xfer =
1649			calc_sync_xfer(period * 4, length);
1650	    }
1651	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1652	    break;
1653#else
1654	    /* We do not accept synchronous transfers.  Respond with a
1655	     * MESSAGE_REJECT.
1656	     */
1657#endif
1658
1659	case EXTENDED_WDTR:
1660	    /* The WD33C93A is only 8-bit.  We respond with a MESSAGE_REJECT
1661	     * to a wide data transfer request.
1662	     */
1663	default:
1664	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1665	    msgqueue_flush(&host->scsi.msgs);
1666	    msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1667	    break;
1668	}
1669	break;
1670
1671#ifdef CONFIG_SCSI_ACORNSCSI_LINK
1672    case LINKED_CMD_COMPLETE:
1673    case LINKED_FLG_CMD_COMPLETE:
1674	/*
1675	 * We don't support linked commands yet
1676	 */
1677	if (0) {
1678#if (DEBUG & DEBUG_LINK)
1679	    printk("scsi%d.%c: lun %d tag %d linked command complete\n",
1680		    host->host->host_no, acornscsi_target(host), host->SCpnt->tag);
1681#endif
1682	    /*
1683	     * A linked command should only terminate with one of these messages
1684	     * if there are more linked commands available.
1685	     */
1686	    if (!host->SCpnt->next_link) {
1687		printk(KERN_WARNING "scsi%d.%c: lun %d tag %d linked command complete, but no next_link\n",
1688			instance->host_no, acornscsi_target(host), host->SCpnt->tag);
1689		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1690		msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1691	    } else {
1692		struct scsi_cmnd *SCpnt = host->SCpnt;
1693
1694		acornscsi_dma_cleanup(host);
1695
1696		host->SCpnt = host->SCpnt->next_link;
1697		host->SCpnt->tag = SCpnt->tag;
1698		SCpnt->result = DID_OK | host->scsi.SCp.Message << 8 | host->Scsi.SCp.Status;
1699		SCpnt->done(SCpnt);
1700
1701		/* initialise host->SCpnt->SCp */
1702	    }
1703	    break;
1704	}
1705#endif
1706
1707    default: /* reject message */
1708	printk(KERN_ERR "scsi%d.%c: unrecognised message %02X, rejecting\n",
1709		host->host->host_no, acornscsi_target(host),
1710		message[0]);
1711	acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1712	msgqueue_flush(&host->scsi.msgs);
1713	msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1714	host->scsi.phase = PHASE_MSGIN;
1715	break;
1716    }
1717    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1718}
1719
1720/*
1721 * Function: int acornscsi_buildmessages(AS_Host *host)
1722 * Purpose : build the connection messages for a host
1723 * Params  : host - host to add messages to
1724 */
1725static
1726void acornscsi_buildmessages(AS_Host *host)
1727{
1728#if 0
1729    /* does the device need resetting? */
1730    if (cmd_reset) {
1731	msgqueue_addmsg(&host->scsi.msgs, 1, BUS_DEVICE_RESET);
1732	return;
1733    }
1734#endif
1735
1736    msgqueue_addmsg(&host->scsi.msgs, 1,
1737		     IDENTIFY(host->device[host->SCpnt->device->id].disconnect_ok,
1738			     host->SCpnt->device->lun));
1739
1740#if 0
1741    /* does the device need the current command aborted */
1742    if (cmd_aborted) {
1743	acornscsi_abortcmd(host->SCpnt->tag);
1744	return;
1745    }
1746#endif
1747
1748#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1749    if (host->SCpnt->tag) {
1750	unsigned int tag_type;
1751
1752	if (host->SCpnt->cmnd[0] == REQUEST_SENSE ||
1753	    host->SCpnt->cmnd[0] == TEST_UNIT_READY ||
1754	    host->SCpnt->cmnd[0] == INQUIRY)
1755	    tag_type = HEAD_OF_QUEUE_TAG;
1756	else
1757	    tag_type = SIMPLE_QUEUE_TAG;
1758	msgqueue_addmsg(&host->scsi.msgs, 2, tag_type, host->SCpnt->tag);
1759    }
1760#endif
1761
1762#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1763    if (host->device[host->SCpnt->device->id].sync_state == SYNC_NEGOCIATE) {
1764	host->device[host->SCpnt->device->id].sync_state = SYNC_SENT_REQUEST;
1765	msgqueue_addmsg(&host->scsi.msgs, 5,
1766			 EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
1767			 sdtr_period / 4, sdtr_size);
1768    }
1769#endif
1770}
1771
1772/*
1773 * Function: int acornscsi_starttransfer(AS_Host *host)
1774 * Purpose : transfer data to/from connected target
1775 * Params  : host - host to which target is connected
1776 * Returns : 0 if failure
1777 */
1778static
1779int acornscsi_starttransfer(AS_Host *host)
1780{
1781    int residual;
1782
1783    if (!host->scsi.SCp.ptr /*&& host->scsi.SCp.this_residual*/) {
1784	printk(KERN_ERR "scsi%d.%c: null buffer passed to acornscsi_starttransfer\n",
1785		host->host->host_no, acornscsi_target(host));
1786	return 0;
1787    }
1788
1789    residual = scsi_bufflen(host->SCpnt) - host->scsi.SCp.scsi_xferred;
1790
1791    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1792    sbic_arm_writenext(host, residual >> 16);
1793    sbic_arm_writenext(host, residual >> 8);
1794    sbic_arm_writenext(host, residual);
1795    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1796    return 1;
1797}
1798
1799/* =========================================================================================
1800 * Connection & Disconnection
1801 */
1802/*
1803 * Function : acornscsi_reconnect(AS_Host *host)
1804 * Purpose  : reconnect a previously disconnected command
1805 * Params   : host - host specific data
1806 * Remarks  : SCSI spec says:
1807 *		'The set of active pointers is restored from the set
1808 *		 of saved pointers upon reconnection of the I/O process'
1809 */
1810static
1811int acornscsi_reconnect(AS_Host *host)
1812{
1813    unsigned int target, lun, ok = 0;
1814
1815    target = sbic_arm_read(host, SBIC_SOURCEID);
1816
1817    if (!(target & 8))
1818	printk(KERN_ERR "scsi%d: invalid source id after reselection "
1819		"- device fault?\n",
1820		host->host->host_no);
1821
1822    target &= 7;
1823
1824    if (host->SCpnt && !host->scsi.disconnectable) {
1825	printk(KERN_ERR "scsi%d.%d: reconnected while command in "
1826		"progress to target %d?\n",
1827		host->host->host_no, target, host->SCpnt->device->id);
1828	host->SCpnt = NULL;
1829    }
1830
1831    lun = sbic_arm_read(host, SBIC_DATA) & 7;
1832
1833    host->scsi.reconnected.target = target;
1834    host->scsi.reconnected.lun = lun;
1835    host->scsi.reconnected.tag = 0;
1836
1837    if (host->scsi.disconnectable && host->SCpnt &&
1838	host->SCpnt->device->id == target && host->SCpnt->device->lun == lun)
1839	ok = 1;
1840
1841    if (!ok && queue_probetgtlun(&host->queues.disconnected, target, lun))
1842	ok = 1;
1843
1844    ADD_STATUS(target, 0x81, host->scsi.phase, 0);
1845
1846    if (ok) {
1847	host->scsi.phase = PHASE_RECONNECTED;
1848    } else {
1849	/* this doesn't seem to work */
1850	printk(KERN_ERR "scsi%d.%c: reselected with no command "
1851		"to reconnect with\n",
1852		host->host->host_no, '0' + target);
1853	acornscsi_dumplog(host, target);
1854	acornscsi_abortcmd(host, 0);
1855	if (host->SCpnt) {
1856	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1857	    host->SCpnt = NULL;
1858	}
1859    }
1860    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1861    return !ok;
1862}
1863
1864/*
1865 * Function: int acornscsi_reconect_finish(AS_Host *host)
1866 * Purpose : finish reconnecting a command
1867 * Params  : host - host to complete
1868 * Returns : 0 if failed
1869 */
1870static
1871int acornscsi_reconnect_finish(AS_Host *host)
1872{
1873    if (host->scsi.disconnectable && host->SCpnt) {
1874	host->scsi.disconnectable = 0;
1875	if (host->SCpnt->device->id  == host->scsi.reconnected.target &&
1876	    host->SCpnt->device->lun == host->scsi.reconnected.lun &&
1877	    host->SCpnt->tag         == host->scsi.reconnected.tag) {
1878#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1879	    DBG(host->SCpnt, printk("scsi%d.%c: reconnected",
1880		    host->host->host_no, acornscsi_target(host)));
1881#endif
1882	} else {
1883	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1884#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1885	    DBG(host->SCpnt, printk("scsi%d.%c: had to move command "
1886		    "to disconnected queue\n",
1887		    host->host->host_no, acornscsi_target(host)));
1888#endif
1889	    host->SCpnt = NULL;
1890	}
1891    }
1892    if (!host->SCpnt) {
1893	host->SCpnt = queue_remove_tgtluntag(&host->queues.disconnected,
1894				host->scsi.reconnected.target,
1895				host->scsi.reconnected.lun,
1896				host->scsi.reconnected.tag);
1897#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1898	DBG(host->SCpnt, printk("scsi%d.%c: had to get command",
1899		host->host->host_no, acornscsi_target(host)));
1900#endif
1901    }
1902
1903    if (!host->SCpnt)
1904	acornscsi_abortcmd(host, host->scsi.reconnected.tag);
1905    else {
1906	/*
1907	 * Restore data pointer from SAVED pointers.
1908	 */
1909	host->scsi.SCp = host->SCpnt->SCp;
1910#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1911	printk(", data pointers: [%p, %X]",
1912		host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
1913#endif
1914    }
1915#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1916    printk("\n");
1917#endif
1918
1919    host->dma.transferred = host->scsi.SCp.scsi_xferred;
1920
1921    return host->SCpnt != NULL;
1922}
1923
1924/*
1925 * Function: void acornscsi_disconnect_unexpected(AS_Host *host)
1926 * Purpose : handle an unexpected disconnect
1927 * Params  : host - host on which disconnect occurred
1928 */
1929static
1930void acornscsi_disconnect_unexpected(AS_Host *host)
1931{
1932    printk(KERN_ERR "scsi%d.%c: unexpected disconnect\n",
1933	    host->host->host_no, acornscsi_target(host));
1934#if (DEBUG & DEBUG_ABORT)
1935    acornscsi_dumplog(host, 8);
1936#endif
1937
1938    acornscsi_done(host, &host->SCpnt, DID_ERROR);
1939}
1940
1941/*
1942 * Function: void acornscsi_abortcmd(AS_host *host, unsigned char tag)
1943 * Purpose : abort a currently executing command
1944 * Params  : host - host with connected command to abort
1945 *	     tag  - tag to abort
1946 */
1947static
1948void acornscsi_abortcmd(AS_Host *host, unsigned char tag)
1949{
1950    host->scsi.phase = PHASE_ABORTED;
1951    sbic_arm_write(host, SBIC_CMND, CMND_ASSERTATN);
1952
1953    msgqueue_flush(&host->scsi.msgs);
1954#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1955    if (tag)
1956	msgqueue_addmsg(&host->scsi.msgs, 2, ABORT_TAG, tag);
1957    else
1958#endif
1959	msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1960}
1961
1962/* ==========================================================================================
1963 * Interrupt routines.
1964 */
1965/*
1966 * Function: int acornscsi_sbicintr(AS_Host *host)
1967 * Purpose : handle interrupts from SCSI device
1968 * Params  : host - host to process
1969 * Returns : INTR_PROCESS if expecting another SBIC interrupt
1970 *	     INTR_IDLE if no interrupt
1971 *	     INTR_NEXT_COMMAND if we have finished processing the command
1972 */
1973static
1974intr_ret_t acornscsi_sbicintr(AS_Host *host, int in_irq)
1975{
1976    unsigned int asr, ssr;
1977
1978    asr = sbic_arm_read(host, SBIC_ASR);
1979    if (!(asr & ASR_INT))
1980	return INTR_IDLE;
1981
1982    ssr = sbic_arm_read(host, SBIC_SSR);
1983
1984#if (DEBUG & DEBUG_PHASES)
1985    print_sbic_status(asr, ssr, host->scsi.phase);
1986#endif
1987
1988    ADD_STATUS(8, ssr, host->scsi.phase, in_irq);
1989
1990    if (host->SCpnt && !host->scsi.disconnectable)
1991	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
1992
1993    switch (ssr) {
1994    case 0x00:				/* reset state - not advanced			*/
1995	printk(KERN_ERR "scsi%d: reset in standard mode but wanted advanced mode.\n",
1996		host->host->host_no);
1997	/* setup sbic - WD33C93A */
1998	sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
1999	sbic_arm_write(host, SBIC_CMND, CMND_RESET);
2000	return INTR_IDLE;
2001
2002    case 0x01:				/* reset state - advanced			*/
2003	sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
2004	sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
2005	sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
2006	sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
2007	msgqueue_flush(&host->scsi.msgs);
2008	return INTR_IDLE;
2009
2010    case 0x41:				/* unexpected disconnect aborted command	*/
2011	acornscsi_disconnect_unexpected(host);
2012	return INTR_NEXT_COMMAND;
2013    }
2014
2015    switch (host->scsi.phase) {
2016    case PHASE_CONNECTING:		/* STATE: command removed from issue queue	*/
2017	switch (ssr) {
2018	case 0x11:			/* -> PHASE_CONNECTED				*/
2019	    /* BUS FREE -> SELECTION */
2020	    host->scsi.phase = PHASE_CONNECTED;
2021	    msgqueue_flush(&host->scsi.msgs);
2022	    host->dma.transferred = host->scsi.SCp.scsi_xferred;
2023	    /* 33C93 gives next interrupt indicating bus phase */
2024	    asr = sbic_arm_read(host, SBIC_ASR);
2025	    if (!(asr & ASR_INT))
2026		break;
2027	    ssr = sbic_arm_read(host, SBIC_SSR);
2028	    ADD_STATUS(8, ssr, host->scsi.phase, 1);
2029	    ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, 1);
2030	    goto connected;
2031	    
2032	case 0x42:			/* select timed out				*/
2033					/* -> PHASE_IDLE				*/
2034	    acornscsi_done(host, &host->SCpnt, DID_NO_CONNECT);
2035	    return INTR_NEXT_COMMAND;
2036
2037	case 0x81:			/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2038	    /* BUS FREE -> RESELECTION */
2039	    host->origSCpnt = host->SCpnt;
2040	    host->SCpnt = NULL;
2041	    msgqueue_flush(&host->scsi.msgs);
2042	    acornscsi_reconnect(host);
2043	    break;
2044
2045	default:
2046	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTING, SSR %02X?\n",
2047		    host->host->host_no, acornscsi_target(host), ssr);
2048	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2049	    acornscsi_abortcmd(host, host->SCpnt->tag);
2050	}
2051	return INTR_PROCESSING;
2052
2053    connected:
2054    case PHASE_CONNECTED:		/* STATE: device selected ok			*/
2055	switch (ssr) {
2056#ifdef NONSTANDARD
2057	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2058	    /* SELECTION -> COMMAND */
2059	    acornscsi_sendcommand(host);
2060	    break;
2061
2062	case 0x8b:			/* -> PHASE_STATUS				*/
2063	    /* SELECTION -> STATUS */
2064	    acornscsi_readstatusbyte(host);
2065	    host->scsi.phase = PHASE_STATUSIN;
2066	    break;
2067#endif
2068
2069	case 0x8e:			/* -> PHASE_MSGOUT				*/
2070	    /* SELECTION ->MESSAGE OUT */
2071	    host->scsi.phase = PHASE_MSGOUT;
2072	    acornscsi_buildmessages(host);
2073	    acornscsi_sendmessage(host);
2074	    break;
2075
2076	/* these should not happen */
2077	case 0x85:			/* target disconnected				*/
2078	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2079	    break;
2080
2081	default:
2082	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTED, SSR %02X?\n",
2083		    host->host->host_no, acornscsi_target(host), ssr);
2084	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2085	    acornscsi_abortcmd(host, host->SCpnt->tag);
2086	}
2087	return INTR_PROCESSING;
2088
2089    case PHASE_MSGOUT:			/* STATE: connected & sent IDENTIFY message	*/
2090	/*
2091	 * SCSI standard says that MESSAGE OUT phases can be followed by a
2092	 * DATA phase, STATUS phase, MESSAGE IN phase or COMMAND phase
2093	 */
2094	switch (ssr) {
2095	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2096	case 0x1a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2097	    /* MESSAGE OUT -> COMMAND */
2098	    acornscsi_sendcommand(host);
2099	    break;
2100
2101	case 0x8b:			/* -> PHASE_STATUS				*/
2102	case 0x1b:			/* -> PHASE_STATUS				*/
2103	    /* MESSAGE OUT -> STATUS */
2104	    acornscsi_readstatusbyte(host);
2105	    host->scsi.phase = PHASE_STATUSIN;
2106	    break;
2107
2108	case 0x8e:			/* -> PHASE_MSGOUT				*/
2109	    /* MESSAGE_OUT(MESSAGE_IN) ->MESSAGE OUT */
2110	    acornscsi_sendmessage(host);
2111	    break;
2112
2113	case 0x4f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2114	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2115	    /* MESSAGE OUT -> MESSAGE IN */
2116	    acornscsi_message(host);
2117	    break;
2118
2119	default:
2120	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGOUT, SSR %02X?\n",
2121		    host->host->host_no, acornscsi_target(host), ssr);
2122	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2123	}
2124	return INTR_PROCESSING;
2125
2126    case PHASE_COMMAND: 		/* STATE: connected & command sent		*/
2127	switch (ssr) {
2128	case 0x18:			/* -> PHASE_DATAOUT				*/
2129	    /* COMMAND -> DATA OUT */
2130	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2131		acornscsi_abortcmd(host, host->SCpnt->tag);
2132	    acornscsi_dma_setup(host, DMA_OUT);
2133	    if (!acornscsi_starttransfer(host))
2134		acornscsi_abortcmd(host, host->SCpnt->tag);
2135	    host->scsi.phase = PHASE_DATAOUT;
2136	    return INTR_IDLE;
2137
2138	case 0x19:			/* -> PHASE_DATAIN				*/
2139	    /* COMMAND -> DATA IN */
2140	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2141		acornscsi_abortcmd(host, host->SCpnt->tag);
2142	    acornscsi_dma_setup(host, DMA_IN);
2143	    if (!acornscsi_starttransfer(host))
2144		acornscsi_abortcmd(host, host->SCpnt->tag);
2145	    host->scsi.phase = PHASE_DATAIN;
2146	    return INTR_IDLE;
2147
2148	case 0x1b:			/* -> PHASE_STATUS				*/
2149	    /* COMMAND -> STATUS */
2150	    acornscsi_readstatusbyte(host);
2151	    host->scsi.phase = PHASE_STATUSIN;
2152	    break;
2153
2154	case 0x1e:			/* -> PHASE_MSGOUT				*/
2155	    /* COMMAND -> MESSAGE OUT */
2156	    acornscsi_sendmessage(host);
2157	    break;
2158
2159	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2160	    /* COMMAND -> MESSAGE IN */
2161	    acornscsi_message(host);
2162	    break;
2163
2164	default:
2165	    printk(KERN_ERR "scsi%d.%c: PHASE_COMMAND, SSR %02X?\n",
2166		    host->host->host_no, acornscsi_target(host), ssr);
2167	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2168	}
2169	return INTR_PROCESSING;
2170
2171    case PHASE_DISCONNECT:		/* STATE: connected, received DISCONNECT msg	*/
2172	if (ssr == 0x85) {		/* -> PHASE_IDLE				*/
2173	    host->scsi.disconnectable = 1;
2174	    host->scsi.reconnected.tag = 0;
2175	    host->scsi.phase = PHASE_IDLE;
2176	    host->stats.disconnects += 1;
2177	} else {
2178	    printk(KERN_ERR "scsi%d.%c: PHASE_DISCONNECT, SSR %02X instead of disconnect?\n",
2179		    host->host->host_no, acornscsi_target(host), ssr);
2180	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2181	}
2182	return INTR_NEXT_COMMAND;
2183
2184    case PHASE_IDLE:			/* STATE: disconnected				*/
2185	if (ssr == 0x81)		/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2186	    acornscsi_reconnect(host);
2187	else {
2188	    printk(KERN_ERR "scsi%d.%c: PHASE_IDLE, SSR %02X while idle?\n",
2189		    host->host->host_no, acornscsi_target(host), ssr);
2190	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2191	}
2192	return INTR_PROCESSING;
2193
2194    case PHASE_RECONNECTED:		/* STATE: device reconnected to initiator	*/
2195	/*
2196	 * Command reconnected - if MESGIN, get message - it may be
2197	 * the tag.  If not, get command out of disconnected queue
2198	 */
2199	/*
2200	 * If we reconnected and we're not in MESSAGE IN phase after IDENTIFY,
2201	 * reconnect I_T_L command
2202	 */
2203	if (ssr != 0x8f && !acornscsi_reconnect_finish(host))
2204	    return INTR_IDLE;
2205	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
2206	switch (ssr) {
2207	case 0x88:			/* data out phase				*/
2208					/* -> PHASE_DATAOUT				*/
2209	    /* MESSAGE IN -> DATA OUT */
2210	    acornscsi_dma_setup(host, DMA_OUT);
2211	    if (!acornscsi_starttransfer(host))
2212		acornscsi_abortcmd(host, host->SCpnt->tag);
2213	    host->scsi.phase = PHASE_DATAOUT;
2214	    return INTR_IDLE;
2215
2216	case 0x89:			/* data in phase				*/
2217					/* -> PHASE_DATAIN				*/
2218	    /* MESSAGE IN -> DATA IN */
2219	    acornscsi_dma_setup(host, DMA_IN);
2220	    if (!acornscsi_starttransfer(host))
2221		acornscsi_abortcmd(host, host->SCpnt->tag);
2222	    host->scsi.phase = PHASE_DATAIN;
2223	    return INTR_IDLE;
2224
2225	case 0x8a:			/* command out					*/
2226	    /* MESSAGE IN -> COMMAND */
2227	    acornscsi_sendcommand(host);/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2228	    break;
2229
2230	case 0x8b:			/* status in					*/
2231					/* -> PHASE_STATUSIN				*/
2232	    /* MESSAGE IN -> STATUS */
2233	    acornscsi_readstatusbyte(host);
2234	    host->scsi.phase = PHASE_STATUSIN;
2235	    break;
2236
2237	case 0x8e:			/* message out					*/
2238					/* -> PHASE_MSGOUT				*/
2239	    /* MESSAGE IN -> MESSAGE OUT */
2240	    acornscsi_sendmessage(host);
2241	    break;
2242
2243	case 0x8f:			/* message in					*/
2244	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2245	    break;
2246
2247	default:
2248	    printk(KERN_ERR "scsi%d.%c: PHASE_RECONNECTED, SSR %02X after reconnect?\n",
2249		    host->host->host_no, acornscsi_target(host), ssr);
2250	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2251	}
2252	return INTR_PROCESSING;
2253
2254    case PHASE_DATAIN:			/* STATE: transferred data in			*/
2255	/*
2256	 * This is simple - if we disconnect then the DMA address & count is
2257	 * correct.
2258	 */
2259	switch (ssr) {
2260	case 0x19:			/* -> PHASE_DATAIN				*/
2261	case 0x89:			/* -> PHASE_DATAIN				*/
2262	    acornscsi_abortcmd(host, host->SCpnt->tag);
2263	    return INTR_IDLE;
2264
2265	case 0x1b:			/* -> PHASE_STATUSIN				*/
2266	case 0x4b:			/* -> PHASE_STATUSIN				*/
2267	case 0x8b:			/* -> PHASE_STATUSIN				*/
2268	    /* DATA IN -> STATUS */
2269	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2270					  acornscsi_sbic_xfcount(host);
2271	    acornscsi_dma_stop(host);
2272	    acornscsi_readstatusbyte(host);
2273	    host->scsi.phase = PHASE_STATUSIN;
2274	    break;
2275
2276	case 0x1e:			/* -> PHASE_MSGOUT				*/
2277	case 0x4e:			/* -> PHASE_MSGOUT				*/
2278	case 0x8e:			/* -> PHASE_MSGOUT				*/
2279	    /* DATA IN -> MESSAGE OUT */
2280	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2281					  acornscsi_sbic_xfcount(host);
2282	    acornscsi_dma_stop(host);
2283	    acornscsi_sendmessage(host);
2284	    break;
2285
2286	case 0x1f:			/* message in					*/
2287	case 0x4f:			/* message in					*/
2288	case 0x8f:			/* message in					*/
2289	    /* DATA IN -> MESSAGE IN */
2290	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2291					  acornscsi_sbic_xfcount(host);
2292	    acornscsi_dma_stop(host);
2293	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2294	    break;
2295
2296	default:
2297	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAIN, SSR %02X?\n",
2298		    host->host->host_no, acornscsi_target(host), ssr);
2299	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2300	}
2301	return INTR_PROCESSING;
2302
2303    case PHASE_DATAOUT: 		/* STATE: transferred data out			*/
2304	/*
2305	 * This is more complicated - if we disconnect, the DMA could be 12
2306	 * bytes ahead of us.  We need to correct this.
2307	 */
2308	switch (ssr) {
2309	case 0x18:			/* -> PHASE_DATAOUT				*/
2310	case 0x88:			/* -> PHASE_DATAOUT				*/
2311	    acornscsi_abortcmd(host, host->SCpnt->tag);
2312	    return INTR_IDLE;
2313
2314	case 0x1b:			/* -> PHASE_STATUSIN				*/
2315	case 0x4b:			/* -> PHASE_STATUSIN				*/
2316	case 0x8b:			/* -> PHASE_STATUSIN				*/
2317	    /* DATA OUT -> STATUS */
2318	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2319					  acornscsi_sbic_xfcount(host);
2320	    acornscsi_dma_stop(host);
2321	    acornscsi_dma_adjust(host);
2322	    acornscsi_readstatusbyte(host);
2323	    host->scsi.phase = PHASE_STATUSIN;
2324	    break;
2325
2326	case 0x1e:			/* -> PHASE_MSGOUT				*/
2327	case 0x4e:			/* -> PHASE_MSGOUT				*/
2328	case 0x8e:			/* -> PHASE_MSGOUT				*/
2329	    /* DATA OUT -> MESSAGE OUT */
2330	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2331					  acornscsi_sbic_xfcount(host);
2332	    acornscsi_dma_stop(host);
2333	    acornscsi_dma_adjust(host);
2334	    acornscsi_sendmessage(host);
2335	    break;
2336
2337	case 0x1f:			/* message in					*/
2338	case 0x4f:			/* message in					*/
2339	case 0x8f:			/* message in					*/
2340	    /* DATA OUT -> MESSAGE IN */
2341	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2342					  acornscsi_sbic_xfcount(host);
2343	    acornscsi_dma_stop(host);
2344	    acornscsi_dma_adjust(host);
2345	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2346	    break;
2347
2348	default:
2349	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAOUT, SSR %02X?\n",
2350		    host->host->host_no, acornscsi_target(host), ssr);
2351	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2352	}
2353	return INTR_PROCESSING;
2354
2355    case PHASE_STATUSIN:		/* STATE: status in complete			*/
2356	switch (ssr) {
2357	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2358	case 0x8f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2359	    /* STATUS -> MESSAGE IN */
2360	    acornscsi_message(host);
2361	    break;
2362
2363	case 0x1e:			/* -> PHASE_MSGOUT				*/
2364	case 0x8e:			/* -> PHASE_MSGOUT				*/
2365	    /* STATUS -> MESSAGE OUT */
2366	    acornscsi_sendmessage(host);
2367	    break;
2368
2369	default:
2370	    printk(KERN_ERR "scsi%d.%c: PHASE_STATUSIN, SSR %02X instead of MESSAGE_IN?\n",
2371		    host->host->host_no, acornscsi_target(host), ssr);
2372	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2373	}
2374	return INTR_PROCESSING;
2375
2376    case PHASE_MSGIN:			/* STATE: message in				*/
2377	switch (ssr) {
2378	case 0x1e:			/* -> PHASE_MSGOUT				*/
2379	case 0x4e:			/* -> PHASE_MSGOUT				*/
2380	case 0x8e:			/* -> PHASE_MSGOUT				*/
2381	    /* MESSAGE IN -> MESSAGE OUT */
2382	    acornscsi_sendmessage(host);
2383	    break;
2384
2385	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2386	case 0x2f:
2387	case 0x4f:
2388	case 0x8f:
2389	    acornscsi_message(host);
2390	    break;
2391
2392	case 0x85:
2393	    printk("scsi%d.%c: strange message in disconnection\n",
2394		host->host->host_no, acornscsi_target(host));
2395	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2396	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2397	    break;
2398
2399	default:
2400	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGIN, SSR %02X after message in?\n",
2401		    host->host->host_no, acornscsi_target(host), ssr);
2402	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2403	}
2404	return INTR_PROCESSING;
2405
2406    case PHASE_DONE:			/* STATE: received status & message		*/
2407	switch (ssr) {
2408	case 0x85:			/* -> PHASE_IDLE				*/
2409	    acornscsi_done(host, &host->SCpnt, DID_OK);
2410	    return INTR_NEXT_COMMAND;
2411
2412	case 0x1e:
2413	case 0x8e:
2414	    acornscsi_sendmessage(host);
2415	    break;
2416
2417	default:
2418	    printk(KERN_ERR "scsi%d.%c: PHASE_DONE, SSR %02X instead of disconnect?\n",
2419		    host->host->host_no, acornscsi_target(host), ssr);
2420	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2421	}
2422	return INTR_PROCESSING;
2423
2424    case PHASE_ABORTED:
2425	switch (ssr) {
2426	case 0x85:
2427	    if (host->SCpnt)
2428		acornscsi_done(host, &host->SCpnt, DID_ABORT);
2429	    else {
2430		clear_bit(host->scsi.reconnected.target * 8 + host->scsi.reconnected.lun,
2431			  host->busyluns);
2432		host->scsi.phase = PHASE_IDLE;
2433	    }
2434	    return INTR_NEXT_COMMAND;
2435
2436	case 0x1e:
2437	case 0x2e:
2438	case 0x4e:
2439	case 0x8e:
2440	    acornscsi_sendmessage(host);
2441	    break;
2442
2443	default:
2444	    printk(KERN_ERR "scsi%d.%c: PHASE_ABORTED, SSR %02X?\n",
2445		    host->host->host_no, acornscsi_target(host), ssr);
2446	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2447	}
2448	return INTR_PROCESSING;
2449
2450    default:
2451	printk(KERN_ERR "scsi%d.%c: unknown driver phase %d\n",
2452		host->host->host_no, acornscsi_target(host), ssr);
2453	acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2454    }
2455    return INTR_PROCESSING;
2456}
2457
2458/*
2459 * Prototype: void acornscsi_intr(int irq, void *dev_id)
2460 * Purpose  : handle interrupts from Acorn SCSI card
2461 * Params   : irq    - interrupt number
2462 *	      dev_id - device specific data (AS_Host structure)
2463 */
2464static irqreturn_t
2465acornscsi_intr(int irq, void *dev_id)
2466{
2467    AS_Host *host = (AS_Host *)dev_id;
2468    intr_ret_t ret;
2469    int iostatus;
2470    int in_irq = 0;
2471
2472    do {
2473	ret = INTR_IDLE;
2474
2475	iostatus = readb(host->fast + INT_REG);
2476
2477	if (iostatus & 2) {
2478	    acornscsi_dma_intr(host);
2479	    iostatus = readb(host->fast + INT_REG);
2480	}
2481
2482	if (iostatus & 8)
2483	    ret = acornscsi_sbicintr(host, in_irq);
2484
2485	/*
2486	 * If we have a transfer pending, start it.
2487	 * Only start it if the interface has already started transferring
2488	 * it's data
2489	 */
2490	if (host->dma.xfer_required)
2491	    acornscsi_dma_xfer(host);
2492
2493	if (ret == INTR_NEXT_COMMAND)
2494	    ret = acornscsi_kick(host);
2495
2496	in_irq = 1;
2497    } while (ret != INTR_IDLE);
2498
2499    return IRQ_HANDLED;
2500}
2501
2502/*=============================================================================================
2503 * Interfaces between interrupt handler and rest of scsi code
2504 */
2505
2506/*
2507 * Function : acornscsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2508 * Purpose  : queues a SCSI command
2509 * Params   : cmd  - SCSI command
2510 *	      done - function called on completion, with pointer to command descriptor
2511 * Returns  : 0, or < 0 on error.
2512 */
2513static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt,
2514		       void (*done)(struct scsi_cmnd *))
2515{
2516    AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2517
2518    if (!done) {
2519	/* there should be some way of rejecting errors like this without panicing... */
2520	panic("scsi%d: queuecommand called with NULL done function [cmd=%p]",
2521		host->host->host_no, SCpnt);
2522	return -EINVAL;
2523    }
2524
2525#if (DEBUG & DEBUG_NO_WRITE)
2526    if (acornscsi_cmdtype(SCpnt->cmnd[0]) == CMD_WRITE && (NO_WRITE & (1 << SCpnt->device->id))) {
2527	printk(KERN_CRIT "scsi%d.%c: WRITE attempted with NO_WRITE flag set\n",
2528	    host->host->host_no, '0' + SCpnt->device->id);
2529	SCpnt->result = DID_NO_CONNECT << 16;
2530	done(SCpnt);
2531	return 0;
2532    }
2533#endif
2534
2535    SCpnt->scsi_done = done;
2536    SCpnt->host_scribble = NULL;
2537    SCpnt->result = 0;
2538    SCpnt->tag = 0;
2539    SCpnt->SCp.phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
2540    SCpnt->SCp.sent_command = 0;
2541    SCpnt->SCp.scsi_xferred = 0;
2542
2543    init_SCp(SCpnt);
2544
2545    host->stats.queues += 1;
2546
2547    {
2548	unsigned long flags;
2549
2550	if (!queue_add_cmd_ordered(&host->queues.issue, SCpnt)) {
2551	    SCpnt->result = DID_ERROR << 16;
2552	    done(SCpnt);
2553	    return 0;
2554	}
2555	local_irq_save(flags);
2556	if (host->scsi.phase == PHASE_IDLE)
2557	    acornscsi_kick(host);
2558	local_irq_restore(flags);
2559    }
2560    return 0;
2561}
2562
2563DEF_SCSI_QCMD(acornscsi_queuecmd)
2564
2565/*
2566 * Prototype: void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1, struct scsi_cmnd **SCpntp2, int result)
2567 * Purpose  : pass a result to *SCpntp1, and check if *SCpntp1 = *SCpntp2
2568 * Params   : SCpntp1 - pointer to command to return
2569 *	      SCpntp2 - pointer to command to check
2570 *	      result  - result to pass back to mid-level done function
2571 * Returns  : *SCpntp2 = NULL if *SCpntp1 is the same command structure as *SCpntp2.
2572 */
2573static inline void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1,
2574					  struct scsi_cmnd **SCpntp2,
2575					  int result)
2576{
2577	struct scsi_cmnd *SCpnt = *SCpntp1;
2578
2579    if (SCpnt) {
2580	*SCpntp1 = NULL;
2581
2582	SCpnt->result = result;
2583	SCpnt->scsi_done(SCpnt);
2584    }
2585
2586    if (SCpnt == *SCpntp2)
2587	*SCpntp2 = NULL;
2588}
2589
2590enum res_abort { res_not_running, res_success, res_success_clear, res_snooze };
2591
2592/*
2593 * Prototype: enum res acornscsi_do_abort(struct scsi_cmnd *SCpnt)
2594 * Purpose  : abort a command on this host
2595 * Params   : SCpnt - command to abort
2596 * Returns  : our abort status
2597 */
2598static enum res_abort acornscsi_do_abort(AS_Host *host, struct scsi_cmnd *SCpnt)
2599{
2600	enum res_abort res = res_not_running;
2601
2602	if (queue_remove_cmd(&host->queues.issue, SCpnt)) {
2603		/*
2604		 * The command was on the issue queue, and has not been
2605		 * issued yet.  We can remove the command from the queue,
2606		 * and acknowledge the abort.  Neither the devices nor the
2607		 * interface know about the command.
2608		 */
2609//#if (DEBUG & DEBUG_ABORT)
2610		printk("on issue queue ");
2611//#endif
2612		res = res_success;
2613	} else if (queue_remove_cmd(&host->queues.disconnected, SCpnt)) {
2614		/*
2615		 * The command was on the disconnected queue.  Simply
2616		 * acknowledge the abort condition, and when the target
2617		 * reconnects, we will give it an ABORT message.  The
2618		 * target should then disconnect, and we will clear
2619		 * the busylun bit.
2620		 */
2621//#if (DEBUG & DEBUG_ABORT)
2622		printk("on disconnected queue ");
2623//#endif
2624		res = res_success;
2625	} else if (host->SCpnt == SCpnt) {
2626		unsigned long flags;
2627
2628//#if (DEBUG & DEBUG_ABORT)
2629		printk("executing ");
2630//#endif
2631
2632		local_irq_save(flags);
2633		switch (host->scsi.phase) {
2634		/*
2635		 * If the interface is idle, and the command is 'disconnectable',
2636		 * then it is the same as on the disconnected queue.  We simply
2637		 * remove all traces of the command.  When the target reconnects,
2638		 * we will give it an ABORT message since the command could not
2639		 * be found.  When the target finally disconnects, we will clear
2640		 * the busylun bit.
2641		 */
2642		case PHASE_IDLE:
2643			if (host->scsi.disconnectable) {
2644				host->scsi.disconnectable = 0;
2645				host->SCpnt = NULL;
2646				res = res_success;
2647			}
2648			break;
2649
2650		/*
2651		 * If the command has connected and done nothing further,
2652		 * simply force a disconnect.  We also need to clear the
2653		 * busylun bit.
2654		 */
2655		case PHASE_CONNECTED:
2656			sbic_arm_write(host, SBIC_CMND, CMND_DISCONNECT);
2657			host->SCpnt = NULL;
2658			res = res_success_clear;
2659			break;
2660
2661		default:
2662			acornscsi_abortcmd(host, host->SCpnt->tag);
2663			res = res_snooze;
2664		}
2665		local_irq_restore(flags);
2666	} else if (host->origSCpnt == SCpnt) {
2667		/*
2668		 * The command will be executed next, but a command
2669		 * is currently using the interface.  This is similar to
2670		 * being on the issue queue, except the busylun bit has
2671		 * been set.
2672		 */
2673		host->origSCpnt = NULL;
2674//#if (DEBUG & DEBUG_ABORT)
2675		printk("waiting for execution ");
2676//#endif
2677		res = res_success_clear;
2678	} else
2679		printk("unknown ");
2680
2681	return res;
2682}
2683
2684/*
2685 * Prototype: int acornscsi_abort(struct scsi_cmnd *SCpnt)
2686 * Purpose  : abort a command on this host
2687 * Params   : SCpnt - command to abort
2688 * Returns  : one of SCSI_ABORT_ macros
2689 */
2690int acornscsi_abort(struct scsi_cmnd *SCpnt)
2691{
2692	AS_Host *host = (AS_Host *) SCpnt->device->host->hostdata;
2693	int result;
2694
2695	host->stats.aborts += 1;
2696
2697#if (DEBUG & DEBUG_ABORT)
2698	{
2699		int asr, ssr;
2700		asr = sbic_arm_read(host, SBIC_ASR);
2701		ssr = sbic_arm_read(host, SBIC_SSR);
2702
2703		printk(KERN_WARNING "acornscsi_abort: ");
2704		print_sbic_status(asr, ssr, host->scsi.phase);
2705		acornscsi_dumplog(host, SCpnt->device->id);
2706	}
2707#endif
2708
2709	printk("scsi%d: ", host->host->host_no);
2710
2711	switch (acornscsi_do_abort(host, SCpnt)) {
2712	/*
2713	 * We managed to find the command and cleared it out.
2714	 * We do not expect the command to be executing on the
2715	 * target, but we have set the busylun bit.
2716	 */
2717	case res_success_clear:
2718//#if (DEBUG & DEBUG_ABORT)
2719		printk("clear ");
2720//#endif
2721		clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);
2722
2723	/*
2724	 * We found the command, and cleared it out.  Either
2725	 * the command is still known to be executing on the
2726	 * target, or the busylun bit is not set.
2727	 */
2728	case res_success:
2729//#if (DEBUG & DEBUG_ABORT)
2730		printk("success\n");
2731//#endif
2732		result = SUCCESS;
2733		break;
2734
2735	/*
2736	 * We did find the command, but unfortunately we couldn't
2737	 * unhook it from ourselves.  Wait some more, and if it
2738	 * still doesn't complete, reset the interface.
2739	 */
2740	case res_snooze:
2741//#if (DEBUG & DEBUG_ABORT)
2742		printk("snooze\n");
2743//#endif
2744		result = FAILED;
2745		break;
2746
2747	/*
2748	 * The command could not be found (either because it completed,
2749	 * or it got dropped.
2750	 */
2751	default:
2752	case res_not_running:
2753		acornscsi_dumplog(host, SCpnt->device->id);
2754		result = FAILED;
2755//#if (DEBUG & DEBUG_ABORT)
2756		printk("not running\n");
2757//#endif
2758		break;
2759	}
2760
2761	return result;
2762}
2763
2764/*
2765 * Prototype: int acornscsi_reset(struct scsi_cmnd *SCpnt)
2766 * Purpose  : reset a command on this host/reset this host
2767 * Params   : SCpnt  - command causing reset
2768 * Returns  : one of SCSI_RESET_ macros
2769 */
2770int acornscsi_bus_reset(struct scsi_cmnd *SCpnt)
2771{
2772	AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2773	struct scsi_cmnd *SCptr;
2774    
2775    host->stats.resets += 1;
2776
2777#if (DEBUG & DEBUG_RESET)
2778    {
2779	int asr, ssr;
2780
2781	asr = sbic_arm_read(host, SBIC_ASR);
2782	ssr = sbic_arm_read(host, SBIC_SSR);
2783
2784	printk(KERN_WARNING "acornscsi_reset: ");
2785	print_sbic_status(asr, ssr, host->scsi.phase);
2786	acornscsi_dumplog(host, SCpnt->device->id);
2787    }
2788#endif
2789
2790    acornscsi_dma_stop(host);
2791
2792    /*
2793     * do hard reset.  This resets all devices on this host, and so we
2794     * must set the reset status on all commands.
2795     */
2796    acornscsi_resetcard(host);
2797
2798    while ((SCptr = queue_remove(&host->queues.disconnected)) != NULL)
2799	;
2800
2801    return SUCCESS;
2802}
2803
2804/*==============================================================================================
2805 * initialisation & miscellaneous support
2806 */
2807
2808/*
2809 * Function: char *acornscsi_info(struct Scsi_Host *host)
2810 * Purpose : return a string describing this interface
2811 * Params  : host - host to give information on
2812 * Returns : a constant string
2813 */
2814const
2815char *acornscsi_info(struct Scsi_Host *host)
2816{
2817    static char string[100], *p;
2818
2819    p = string;
2820    
2821    p += sprintf(string, "%s at port %08lX irq %d v%d.%d.%d"
2822#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2823    " SYNC"
2824#endif
2825#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2826    " TAG"
2827#endif
2828#ifdef CONFIG_SCSI_ACORNSCSI_LINK
2829    " LINK"
2830#endif
2831#if (DEBUG & DEBUG_NO_WRITE)
2832    " NOWRITE (" __stringify(NO_WRITE) ")"
2833#endif
2834		, host->hostt->name, host->io_port, host->irq,
2835		VER_MAJOR, VER_MINOR, VER_PATCH);
2836    return string;
2837}
2838
2839int acornscsi_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset,
2840			int length, int inout)
2841{
2842    int pos, begin = 0, devidx;
2843    struct scsi_device *scd;
2844    AS_Host *host;
2845    char *p = buffer;
2846
2847    if (inout == 1)
2848	return -EINVAL;
2849
2850    host  = (AS_Host *)instance->hostdata;
2851    
2852    p += sprintf(p, "AcornSCSI driver v%d.%d.%d"
2853#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2854    " SYNC"
2855#endif
2856#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2857    " TAG"
2858#endif
2859#ifdef CONFIG_SCSI_ACORNSCSI_LINK
2860    " LINK"
2861#endif
2862#if (DEBUG & DEBUG_NO_WRITE)
2863    " NOWRITE (" __stringify(NO_WRITE) ")"
2864#endif
2865		"\n\n", VER_MAJOR, VER_MINOR, VER_PATCH);
2866
2867    p += sprintf(p,	"SBIC: WD33C93A  Address: %p    IRQ : %d\n",
2868			host->base + SBIC_REGIDX, host->scsi.irq);
2869#ifdef USE_DMAC
2870    p += sprintf(p,	"DMAC: uPC71071  Address: %p  IRQ : %d\n\n",
2871			host->base + DMAC_OFFSET, host->scsi.irq);
2872#endif
2873
2874    p += sprintf(p,	"Statistics:\n"
2875			"Queued commands: %-10u    Issued commands: %-10u\n"
2876			"Done commands  : %-10u    Reads          : %-10u\n"
2877			"Writes         : %-10u    Others         : %-10u\n"
2878			"Disconnects    : %-10u    Aborts         : %-10u\n"
2879			"Resets         : %-10u\n\nLast phases:",
2880			host->stats.queues,		host->stats.removes,
2881			host->stats.fins,		host->stats.reads,
2882			host->stats.writes,		host->stats.miscs,
2883			host->stats.disconnects,	host->stats.aborts,
2884			host->stats.resets);
2885
2886    for (devidx = 0; devidx < 9; devidx ++) {
2887	unsigned int statptr, prev;
2888
2889	p += sprintf(p, "\n%c:", devidx == 8 ? 'H' : ('0' + devidx));
2890	statptr = host->status_ptr[devidx] - 10;
2891
2892	if ((signed int)statptr < 0)
2893	    statptr += STATUS_BUFFER_SIZE;
2894
2895	prev = host->status[devidx][statptr].when;
2896
2897	for (; statptr != host->status_ptr[devidx]; statptr = (statptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
2898	    if (host->status[devidx][statptr].when) {
2899		p += sprintf(p, "%c%02X:%02X+%2ld",
2900			host->status[devidx][statptr].irq ? '-' : ' ',
2901			host->status[devidx][statptr].ph,
2902			host->status[devidx][statptr].ssr,
2903			(host->status[devidx][statptr].when - prev) < 100 ?
2904				(host->status[devidx][statptr].when - prev) : 99);
2905		prev = host->status[devidx][statptr].when;
2906	    }
2907	}
2908    }
2909
2910    p += sprintf(p, "\nAttached devices:\n");
2911
2912    shost_for_each_device(scd, instance) {
2913	p += sprintf(p, "Device/Lun TaggedQ      Sync\n");
2914	p += sprintf(p, "     %d/%d   ", scd->id, scd->lun);
2915	if (scd->tagged_supported)
2916		p += sprintf(p, "%3sabled(%3d) ",
2917			     scd->simple_tags ? "en" : "dis",
2918			     scd->current_tag);
2919	else
2920		p += sprintf(p, "unsupported  ");
2921
2922	if (host->device[scd->id].sync_xfer & 15)
2923		p += sprintf(p, "offset %d, %d ns\n",
2924			     host->device[scd->id].sync_xfer & 15,
2925			     acornscsi_getperiod(host->device[scd->id].sync_xfer));
2926	else
2927		p += sprintf(p, "async\n");
2928
2929	pos = p - buffer;
2930	if (pos + begin < offset) {
2931	    begin += pos;
2932	    p = buffer;
2933	}
2934	pos = p - buffer;
2935	if (pos + begin > offset + length) {
2936	    scsi_device_put(scd);
2937	    break;
2938	}
2939    }
2940
2941    pos = p - buffer;
2942
2943    *start = buffer + (offset - begin);
2944    pos -= offset - begin;
2945
2946    if (pos > length)
2947	pos = length;
2948
2949    return pos;
2950}
2951
2952static struct scsi_host_template acornscsi_template = {
2953	.module			= THIS_MODULE,
2954	.proc_info		= acornscsi_proc_info,
2955	.name			= "AcornSCSI",
2956	.info			= acornscsi_info,
2957	.queuecommand		= acornscsi_queuecmd,
2958	.eh_abort_handler	= acornscsi_abort,
2959	.eh_bus_reset_handler	= acornscsi_bus_reset,
2960	.can_queue		= 16,
2961	.this_id		= 7,
2962	.sg_tablesize		= SG_ALL,
2963	.cmd_per_lun		= 2,
2964	.use_clustering		= DISABLE_CLUSTERING,
2965	.proc_name		= "acornscsi",
2966};
2967
2968static int __devinit
2969acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
2970{
2971	struct Scsi_Host *host;
2972	AS_Host *ashost;
2973	int ret;
2974
2975	ret = ecard_request_resources(ec);
2976	if (ret)
2977		goto out;
2978
2979	host = scsi_host_alloc(&acornscsi_template, sizeof(AS_Host));
2980	if (!host) {
2981		ret = -ENOMEM;
2982		goto out_release;
2983	}
2984
2985	ashost = (AS_Host *)host->hostdata;
2986
2987	ashost->base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
2988	ashost->fast = ecardm_iomap(ec, ECARD_RES_IOCFAST, 0, 0);
2989	if (!ashost->base || !ashost->fast)
2990		goto out_put;
2991
2992	host->irq = ec->irq;
2993	ashost->host = host;
2994	ashost->scsi.irq = host->irq;
2995
2996	ec->irqaddr	= ashost->fast + INT_REG;
2997	ec->irqmask	= 0x0a;
2998
2999	ret = request_irq(host->irq, acornscsi_intr, IRQF_DISABLED, "acornscsi", ashost);
3000	if (ret) {
3001		printk(KERN_CRIT "scsi%d: IRQ%d not free: %d\n",
3002			host->host_no, ashost->scsi.irq, ret);
3003		goto out_put;
3004	}
3005
3006	memset(&ashost->stats, 0, sizeof (ashost->stats));
3007	queue_initialise(&ashost->queues.issue);
3008	queue_initialise(&ashost->queues.disconnected);
3009	msgqueue_initialise(&ashost->scsi.msgs);
3010
3011	acornscsi_resetcard(ashost);
3012
3013	ret = scsi_add_host(host, &ec->dev);
3014	if (ret)
3015		goto out_irq;
3016
3017	scsi_scan_host(host);
3018	goto out;
3019
3020 out_irq:
3021	free_irq(host->irq, ashost);
3022	msgqueue_free(&ashost->scsi.msgs);
3023	queue_free(&ashost->queues.disconnected);
3024	queue_free(&ashost->queues.issue);
3025 out_put:
3026	ecardm_iounmap(ec, ashost->fast);
3027	ecardm_iounmap(ec, ashost->base);
3028	scsi_host_put(host);
3029 out_release:
3030	ecard_release_resources(ec);
3031 out:
3032	return ret;
3033}
3034
3035static void __devexit acornscsi_remove(struct expansion_card *ec)
3036{
3037	struct Scsi_Host *host = ecard_get_drvdata(ec);
3038	AS_Host *ashost = (AS_Host *)host->hostdata;
3039
3040	ecard_set_drvdata(ec, NULL);
3041	scsi_remove_host(host);
3042
3043	/*
3044	 * Put card into RESET state
3045	 */
3046	writeb(0x80, ashost->fast + PAGE_REG);
3047
3048	free_irq(host->irq, ashost);
3049
3050	msgqueue_free(&ashost->scsi.msgs);
3051	queue_free(&ashost->queues.disconnected);
3052	queue_free(&ashost->queues.issue);
3053	ecardm_iounmap(ec, ashost->fast);
3054	ecardm_iounmap(ec, ashost->base);
3055	scsi_host_put(host);
3056	ecard_release_resources(ec);
3057}
3058
3059static const struct ecard_id acornscsi_cids[] = {
3060	{ MANU_ACORN, PROD_ACORN_SCSI },
3061	{ 0xffff, 0xffff },
3062};
3063
3064static struct ecard_driver acornscsi_driver = {
3065	.probe		= acornscsi_probe,
3066	.remove		= __devexit_p(acornscsi_remove),
3067	.id_table	= acornscsi_cids,
3068	.drv = {
3069		.name		= "acornscsi",
3070	},
3071};
3072
3073static int __init acornscsi_init(void)
3074{
3075	return ecard_register_driver(&acornscsi_driver);
3076}
3077
3078static void __exit acornscsi_exit(void)
3079{
3080	ecard_remove_driver(&acornscsi_driver);
3081}
3082
3083module_init(acornscsi_init);
3084module_exit(acornscsi_exit);
3085
3086MODULE_AUTHOR("Russell King");
3087MODULE_DESCRIPTION("AcornSCSI driver");
3088MODULE_LICENSE("GPL");