1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  linux/drivers/acorn/scsi/acornscsi.c
4 *
5 *  Acorn SCSI 3 driver
6 *  By R.M.King.
7 *
8 * Abandoned using the Select and Transfer command since there were
9 * some nasty races between our software and the target devices that
10 * were not easy to solve, and the device errata had a lot of entries
11 * for this command, some of them quite nasty...
12 *
13 * Changelog:
14 *  26-Sep-1997	RMK	Re-jigged to use the queue module.
15 *			Re-coded state machine to be based on driver
16 *			state not scsi state.  Should be easier to debug.
17 *			Added acornscsi_release to clean up properly.
18 *			Updated proc/scsi reporting.
19 *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
20 *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
21 *			reconnect race condition causing a warning message.
22 *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
23 *  15-Oct-1997	RMK	Improved handling of commands.
24 *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
25 *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
26 *			transitions added to allow dodgy devices to work.
27 */
28#define DEBUG_NO_WRITE	1
29#define DEBUG_QUEUES	2
30#define DEBUG_DMA	4
31#define DEBUG_ABORT	8
32#define DEBUG_DISCON	16
33#define DEBUG_CONNECT	32
34#define DEBUG_PHASES	64
35#define DEBUG_WRITE	128
36#define DEBUG_LINK	256
37#define DEBUG_MESSAGES	512
38#define DEBUG_RESET	1024
39#define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
40			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
41			 DEBUG_DMA|DEBUG_QUEUES)
42
43/* DRIVER CONFIGURATION
44 *
45 * SCSI-II Tagged queue support.
46 *
47 * I don't have any SCSI devices that support it, so it is totally untested
48 * (except to make sure that it doesn't interfere with any non-tagging
49 * devices).  It is not fully implemented either - what happens when a
50 * tagging device reconnects???
51 *
52 * You can tell if you have a device that supports tagged queueing my
53 * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
54 * as '2 TAG'.
55 */
56
57/*
58 * SCSI-II Synchronous transfer support.
59 *
60 * Tried and tested...
61 *
62 * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
63 * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
64 * DEFAULT_PERIOD - default REQ period.
65 */
66#define SDTR_SIZE	12
67#define SDTR_PERIOD	125
68#define DEFAULT_PERIOD	500
69
70/*
71 * Debugging information
72 *
73 * DEBUG	  - bit mask from list above
74 * DEBUG_TARGET   - is defined to the target number if you want to debug
75 *		    a specific target. [only recon/write/dma].
76 */
77#define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
78/* only allow writing to SCSI device 0 */
79#define NO_WRITE 0xFE
80/*#define DEBUG_TARGET 2*/
81/*
82 * Select timeout time (in 10ms units)
83 *
84 * This is the timeout used between the start of selection and the WD33C93
85 * chip deciding that the device isn't responding.
86 */
87#define TIMEOUT_TIME 10
88/*
89 * Define this if you want to have verbose explanation of SCSI
90 * status/messages.
91 */
92#undef CONFIG_ACORNSCSI_CONSTANTS
93/*
94 * Define this if you want to use the on board DMAC [don't remove this option]
95 * If not set, then use PIO mode (not currently supported).
96 */
97#define USE_DMAC
98
99/*
100 * ====================================================================================
101 */
102
103#ifdef DEBUG_TARGET
104#define DBG(cmd,xxx...) \
105  if (cmd->device->id == DEBUG_TARGET) { \
106    xxx; \
107  }
108#else
109#define DBG(cmd,xxx...) xxx
110#endif
111
112#include <linux/module.h>
113#include <linux/kernel.h>
114#include <linux/string.h>
115#include <linux/signal.h>
116#include <linux/errno.h>
117#include <linux/proc_fs.h>
118#include <linux/ioport.h>
119#include <linux/blkdev.h>
120#include <linux/delay.h>
121#include <linux/interrupt.h>
122#include <linux/init.h>
123#include <linux/bitops.h>
124#include <linux/stringify.h>
125#include <linux/io.h>
126
127#include <asm/ecard.h>
128
129#include <scsi/scsi.h>
130#include <scsi/scsi_cmnd.h>
131#include <scsi/scsi_dbg.h>
132#include <scsi/scsi_device.h>
133#include <scsi/scsi_eh.h>
134#include <scsi/scsi_host.h>
135#include <scsi/scsi_tcq.h>
136#include <scsi/scsi_transport_spi.h>
137#include "acornscsi.h"
138#include "msgqueue.h"
139#include "arm_scsi.h"
140
141#include <scsi/scsicam.h>
142
143#define VER_MAJOR 2
144#define VER_MINOR 0
145#define VER_PATCH 6
146
147#ifdef USE_DMAC
148/*
149 * DMAC setup parameters
150 */
151#define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
152#define INIT_DEVCON1	(DEVCON1_BHLD)
153#define DMAC_READ	(MODECON_READ)
154#define DMAC_WRITE	(MODECON_WRITE)
155#define INIT_SBICDMA	(CTRL_DMABURST)
156
157#define scsi_xferred	have_data_in
158
159/*
160 * Size of on-board DMA buffer
161 */
162#define DMAC_BUFFER_SIZE	65536
163#endif
164
165#define STATUS_BUFFER_TO_PRINT	24
166
167unsigned int sdtr_period = SDTR_PERIOD;
168unsigned int sdtr_size   = SDTR_SIZE;
169
170static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
171			   unsigned int result);
172static int acornscsi_reconnect_finish(AS_Host *host);
173static void acornscsi_dma_cleanup(AS_Host *host);
174static void acornscsi_abortcmd(AS_Host *host);
175
176/* ====================================================================================
177 * Miscellaneous
178 */
179
180/* Offsets from MEMC base */
181#define SBIC_REGIDX	0x2000
182#define SBIC_REGVAL	0x2004
183#define DMAC_OFFSET	0x3000
184
185/* Offsets from FAST IOC base */
186#define INT_REG		0x2000
187#define PAGE_REG	0x3000
188
189static inline void sbic_arm_write(AS_Host *host, unsigned int reg, unsigned int value)
190{
191    writeb(reg, host->base + SBIC_REGIDX);
192    writeb(value, host->base + SBIC_REGVAL);
193}
194
195static inline int sbic_arm_read(AS_Host *host, unsigned int reg)
196{
197    if(reg == SBIC_ASR)
198	   return readl(host->base + SBIC_REGIDX) & 255;
199    writeb(reg, host->base + SBIC_REGIDX);
200    return readl(host->base + SBIC_REGVAL) & 255;
201}
202
203#define sbic_arm_writenext(host, val)	writeb((val), (host)->base + SBIC_REGVAL)
204#define sbic_arm_readnext(host) 	readb((host)->base + SBIC_REGVAL)
205
206#ifdef USE_DMAC
207#define dmac_read(host,reg) \
208	readb((host)->base + DMAC_OFFSET + ((reg) << 2))
209
210#define dmac_write(host,reg,value) \
211	({ writeb((value), (host)->base + DMAC_OFFSET + ((reg) << 2)); })
212
213#define dmac_clearintr(host) 	writeb(0, (host)->fast + INT_REG)
214
215static inline unsigned int dmac_address(AS_Host *host)
216{
217    return dmac_read(host, DMAC_TXADRHI) << 16 |
218	   dmac_read(host, DMAC_TXADRMD) << 8 |
219	   dmac_read(host, DMAC_TXADRLO);
220}
221
222static
223void acornscsi_dumpdma(AS_Host *host, char *where)
224{
225	unsigned int mode, addr, len;
226
227	mode = dmac_read(host, DMAC_MODECON);
228	addr = dmac_address(host);
229	len  = dmac_read(host, DMAC_TXCNTHI) << 8 |
230	       dmac_read(host, DMAC_TXCNTLO);
231
232	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
233		host->host->host_no, where,
234		mode, addr, (len + 1) & 0xffff,
235		dmac_read(host, DMAC_MASKREG));
236
237	printk("DMA @%06x, ", host->dma.start_addr);
238	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
239		host->scsi.SCp.this_residual);
240	printk("DT @+%04x ST @+%04x", host->dma.transferred,
241		host->scsi.SCp.scsi_xferred);
242	printk("\n");
243}
244#endif
245
246static
247unsigned long acornscsi_sbic_xfcount(AS_Host *host)
248{
249    unsigned long length;
250
251    length = sbic_arm_read(host, SBIC_TRANSCNTH) << 16;
252    length |= sbic_arm_readnext(host) << 8;
253    length |= sbic_arm_readnext(host);
254
255    return length;
256}
257
258static int
259acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
260{
261	int asr;
262
263	do {
264		asr = sbic_arm_read(host, SBIC_ASR);
265
266		if ((asr & stat_mask) == stat)
267			return 0;
268
269		udelay(1);
270	} while (--timeout);
271
272	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);
273
274	return -1;
275}
276
277static
278int acornscsi_sbic_issuecmd(AS_Host *host, int command)
279{
280    if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
281	return -1;
282
283    sbic_arm_write(host, SBIC_CMND, command);
284
285    return 0;
286}
287
288static void
289acornscsi_csdelay(unsigned int cs)
290{
291    unsigned long target_jiffies, flags;
292
293    target_jiffies = jiffies + 1 + cs * HZ / 100;
294
295    local_save_flags(flags);
296    local_irq_enable();
297
298    while (time_before(jiffies, target_jiffies)) barrier();
299
300    local_irq_restore(flags);
301}
302
303static
304void acornscsi_resetcard(AS_Host *host)
305{
306    unsigned int i, timeout;
307
308    /* assert reset line */
309    host->card.page_reg = 0x80;
310    writeb(host->card.page_reg, host->fast + PAGE_REG);
311
312    /* wait 3 cs.  SCSI standard says 25ms. */
313    acornscsi_csdelay(3);
314
315    host->card.page_reg = 0;
316    writeb(host->card.page_reg, host->fast + PAGE_REG);
317
318    /*
319     * Should get a reset from the card
320     */
321    timeout = 1000;
322    do {
323	if (readb(host->fast + INT_REG) & 8)
324	    break;
325	udelay(1);
326    } while (--timeout);
327
328    if (timeout == 0)
329	printk("scsi%d: timeout while resetting card\n",
330		host->host->host_no);
331
332    sbic_arm_read(host, SBIC_ASR);
333    sbic_arm_read(host, SBIC_SSR);
334
335    /* setup sbic - WD33C93A */
336    sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
337    sbic_arm_write(host, SBIC_CMND, CMND_RESET);
338
339    /*
340     * Command should cause a reset interrupt
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    if (sbic_arm_read(host, SBIC_SSR) != 0x01)
355	printk(KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
356		host->host->host_no);
357
358    sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
359    sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
360    sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
361    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
362
363    host->card.page_reg = 0x40;
364    writeb(host->card.page_reg, host->fast + PAGE_REG);
365
366    /* setup dmac - uPC71071 */
367    dmac_write(host, DMAC_INIT, 0);
368#ifdef USE_DMAC
369    dmac_write(host, DMAC_INIT, INIT_8BIT);
370    dmac_write(host, DMAC_CHANNEL, CHANNEL_0);
371    dmac_write(host, DMAC_DEVCON0, INIT_DEVCON0);
372    dmac_write(host, DMAC_DEVCON1, INIT_DEVCON1);
373#endif
374
375    host->SCpnt = NULL;
376    host->scsi.phase = PHASE_IDLE;
377    host->scsi.disconnectable = 0;
378
379    memset(host->busyluns, 0, sizeof(host->busyluns));
380
381    for (i = 0; i < 8; i++) {
382	host->device[i].sync_state = SYNC_NEGOCIATE;
383	host->device[i].disconnect_ok = 1;
384    }
385
386    /* wait 25 cs.  SCSI standard says 250ms. */
387    acornscsi_csdelay(25);
388}
389
390/*=============================================================================================
391 * Utility routines (eg. debug)
392 */
393#ifdef CONFIG_ACORNSCSI_CONSTANTS
394static char *acornscsi_interrupttype[] = {
395  "rst",  "suc",  "p/a",  "3",
396  "term", "5",	  "6",	  "7",
397  "serv", "9",	  "a",	  "b",
398  "c",	  "d",	  "e",	  "f"
399};
400
401static signed char acornscsi_map[] = {
402  0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
403 -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
404 12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
405 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
406 15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
407 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
408 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
409 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
410 21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
411 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
412 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
413 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
414 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
415 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
416 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
417 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
418};
419
420static char *acornscsi_interruptcode[] = {
421    /* 0 */
422    "reset - normal mode",	/* 00 */
423    "reset - advanced mode",	/* 01 */
424
425    /* 2 */
426    "sel",			/* 11 */
427    "sel+xfer", 		/* 16 */
428    "data-out", 		/* 18 */
429    "data-in",			/* 19 */
430    "cmd",			/* 1A */
431    "stat",			/* 1B */
432    "??-out",			/* 1C */
433    "??-in",			/* 1D */
434    "msg-out",			/* 1E */
435    "msg-in",			/* 1F */
436
437    /* 12 */
438    "/ACK asserted",		/* 20 */
439    "save-data-ptr",		/* 21 */
440    "{re}sel",			/* 22 */
441
442    /* 15 */
443    "inv cmd",			/* 40 */
444    "unexpected disconnect",	/* 41 */
445    "sel timeout",		/* 42 */
446    "P err",			/* 43 */
447    "P err+ATN",		/* 44 */
448    "bad status byte",		/* 47 */
449
450    /* 21 */
451    "resel, no id",		/* 80 */
452    "resel",			/* 81 */
453    "discon",			/* 85 */
454};
455
456static
457void print_scsi_status(unsigned int ssr)
458{
459    if (acornscsi_map[ssr] != -1)
460	printk("%s:%s",
461		acornscsi_interrupttype[(ssr >> 4)],
462		acornscsi_interruptcode[acornscsi_map[ssr]]);
463    else
464	printk("%X:%X", ssr >> 4, ssr & 0x0f);
465}
466#endif
467
468static
469void print_sbic_status(int asr, int ssr, int cmdphase)
470{
471#ifdef CONFIG_ACORNSCSI_CONSTANTS
472    printk("sbic: %c%c%c%c%c%c ",
473	    asr & ASR_INT ? 'I' : 'i',
474	    asr & ASR_LCI ? 'L' : 'l',
475	    asr & ASR_BSY ? 'B' : 'b',
476	    asr & ASR_CIP ? 'C' : 'c',
477	    asr & ASR_PE  ? 'P' : 'p',
478	    asr & ASR_DBR ? 'D' : 'd');
479    printk("scsi: ");
480    print_scsi_status(ssr);
481    printk(" ph %02X\n", cmdphase);
482#else
483    printk("sbic: %02X scsi: %X:%X ph: %02X\n",
484	    asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
485#endif
486}
487
488static void
489acornscsi_dumplogline(AS_Host *host, int target, int line)
490{
491	unsigned long prev;
492	signed int ptr;
493
494	ptr = host->status_ptr[target] - STATUS_BUFFER_TO_PRINT;
495	if (ptr < 0)
496		ptr += STATUS_BUFFER_SIZE;
497
498	printk("%c: %3s:", target == 8 ? 'H' : '0' + target,
499		line == 0 ? "ph" : line == 1 ? "ssr" : "int");
500
501	prev = host->status[target][ptr].when;
502
503	for (; ptr != host->status_ptr[target]; ptr = (ptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
504		unsigned long time_diff;
505
506		if (!host->status[target][ptr].when)
507			continue;
508
509		switch (line) {
510		case 0:
511			printk("%c%02X", host->status[target][ptr].irq ? '-' : ' ',
512					 host->status[target][ptr].ph);
513			break;
514
515		case 1:
516			printk(" %02X", host->status[target][ptr].ssr);
517			break;
518
519		case 2:
520			time_diff = host->status[target][ptr].when - prev;
521			prev = host->status[target][ptr].when;
522			if (time_diff == 0)
523				printk("==^");
524			else if (time_diff >= 100)
525				printk("   ");
526			else
527				printk(" %02ld", time_diff);
528			break;
529		}
530	}
531
532	printk("\n");
533}
534
535static
536void acornscsi_dumplog(AS_Host *host, int target)
537{
538    do {
539	acornscsi_dumplogline(host, target, 0);
540	acornscsi_dumplogline(host, target, 1);
541	acornscsi_dumplogline(host, target, 2);
542
543	if (target == 8)
544	    break;
545
546	target = 8;
547    } while (1);
548}
549
550static
551char acornscsi_target(AS_Host *host)
552{
553	if (host->SCpnt)
554		return '0' + host->SCpnt->device->id;
555	return 'H';
556}
557
558/*
559 * Prototype: cmdtype_t acornscsi_cmdtype(int command)
560 * Purpose  : differentiate READ from WRITE from other commands
561 * Params   : command - command to interpret
562 * Returns  : CMD_READ	- command reads data,
563 *	      CMD_WRITE - command writes data,
564 *	      CMD_MISC	- everything else
565 */
566static inline
567cmdtype_t acornscsi_cmdtype(int command)
568{
569    switch (command) {
570    case WRITE_6:  case WRITE_10:  case WRITE_12:
571	return CMD_WRITE;
572    case READ_6:   case READ_10:   case READ_12:
573	return CMD_READ;
574    default:
575	return CMD_MISC;
576    }
577}
578
579/*
580 * Prototype: int acornscsi_datadirection(int command)
581 * Purpose  : differentiate between commands that have a DATA IN phase
582 *	      and a DATA OUT phase
583 * Params   : command - command to interpret
584 * Returns  : DATADIR_OUT - data out phase expected
585 *	      DATADIR_IN  - data in phase expected
586 */
587static
588datadir_t acornscsi_datadirection(int command)
589{
590    switch (command) {
591    case CHANGE_DEFINITION:	case COMPARE:		case COPY:
592    case COPY_VERIFY:		case LOG_SELECT:	case MODE_SELECT:
593    case MODE_SELECT_10:	case SEND_DIAGNOSTIC:	case WRITE_BUFFER:
594    case FORMAT_UNIT:		case REASSIGN_BLOCKS:	case RESERVE:
595    case SEARCH_EQUAL:		case SEARCH_HIGH:	case SEARCH_LOW:
596    case WRITE_6:		case WRITE_10:		case WRITE_VERIFY:
597    case UPDATE_BLOCK:		case WRITE_LONG:	case WRITE_SAME:
598    case SEARCH_HIGH_12:	case SEARCH_EQUAL_12:	case SEARCH_LOW_12:
599    case WRITE_12:		case WRITE_VERIFY_12:	case SET_WINDOW:
600    case MEDIUM_SCAN:		case SEND_VOLUME_TAG:	case 0xea:
601	return DATADIR_OUT;
602    default:
603	return DATADIR_IN;
604    }
605}
606
607/*
608 * Purpose  : provide values for synchronous transfers with 33C93.
609 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
610 *	Modified by Russell King for 8MHz WD33C93A
611 */
612static struct sync_xfer_tbl {
613    unsigned int period_ns;
614    unsigned char reg_value;
615} sync_xfer_table[] = {
616    {	1, 0x20 },    { 249, 0x20 },	{ 374, 0x30 },
617    { 499, 0x40 },    { 624, 0x50 },	{ 749, 0x60 },
618    { 874, 0x70 },    { 999, 0x00 },	{   0,	  0 }
619};
620
621/*
622 * Prototype: int acornscsi_getperiod(unsigned char syncxfer)
623 * Purpose  : period for the synchronous transfer setting
624 * Params   : syncxfer SYNCXFER register value
625 * Returns  : period in ns.
626 */
627static
628int acornscsi_getperiod(unsigned char syncxfer)
629{
630    int i;
631
632    syncxfer &= 0xf0;
633    if (syncxfer == 0x10)
634	syncxfer = 0;
635
636    for (i = 1; sync_xfer_table[i].period_ns; i++)
637	if (syncxfer == sync_xfer_table[i].reg_value)
638	    return sync_xfer_table[i].period_ns;
639    return 0;
640}
641
642/*
643 * Prototype: int round_period(unsigned int period)
644 * Purpose  : return index into above table for a required REQ period
645 * Params   : period - time (ns) for REQ
646 * Returns  : table index
647 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
648 */
649static inline
650int round_period(unsigned int period)
651{
652    int i;
653
654    for (i = 1; sync_xfer_table[i].period_ns; i++) {
655	if ((period <= sync_xfer_table[i].period_ns) &&
656	    (period > sync_xfer_table[i - 1].period_ns))
657	    return i;
658    }
659    return 7;
660}
661
662/*
663 * Prototype: unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
664 * Purpose  : calculate value for 33c93s SYNC register
665 * Params   : period - time (ns) for REQ
666 *	      offset - offset in bytes between REQ/ACK
667 * Returns  : value for SYNC register
668 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
669 */
670static
671unsigned char __maybe_unused calc_sync_xfer(unsigned int period,
672					    unsigned int offset)
673{
674    return sync_xfer_table[round_period(period)].reg_value |
675		((offset < SDTR_SIZE) ? offset : SDTR_SIZE);
676}
677
678/* ====================================================================================
679 * Command functions
680 */
681/*
682 * Function: acornscsi_kick(AS_Host *host)
683 * Purpose : kick next command to interface
684 * Params  : host - host to send command to
685 * Returns : INTR_IDLE if idle, otherwise INTR_PROCESSING
686 * Notes   : interrupts are always disabled!
687 */
688static
689intr_ret_t acornscsi_kick(AS_Host *host)
690{
691    int from_queue = 0;
692    struct scsi_cmnd *SCpnt;
693
694    /* first check to see if a command is waiting to be executed */
695    SCpnt = host->origSCpnt;
696    host->origSCpnt = NULL;
697
698    /* retrieve next command */
699    if (!SCpnt) {
700	SCpnt = queue_remove_exclude(&host->queues.issue, host->busyluns);
701	if (!SCpnt)
702	    return INTR_IDLE;
703
704	from_queue = 1;
705    }
706
707    if (host->scsi.disconnectable && host->SCpnt) {
708	queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
709	host->scsi.disconnectable = 0;
710#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
711	DBG(host->SCpnt, printk("scsi%d.%c: moved command to disconnected queue\n",
712		host->host->host_no, acornscsi_target(host)));
713#endif
714	host->SCpnt = NULL;
715    }
716
717    /*
718     * If we have an interrupt pending, then we may have been reselected.
719     * In this case, we don't want to write to the registers
720     */
721    if (!(sbic_arm_read(host, SBIC_ASR) & (ASR_INT|ASR_BSY|ASR_CIP))) {
722	sbic_arm_write(host, SBIC_DESTID, SCpnt->device->id);
723	sbic_arm_write(host, SBIC_CMND, CMND_SELWITHATN);
724    }
725
726    /*
727     * claim host busy - all of these must happen atomically wrt
728     * our interrupt routine.  Failure means command loss.
729     */
730    host->scsi.phase = PHASE_CONNECTING;
731    host->SCpnt = SCpnt;
732    host->scsi.SCp = *arm_scsi_pointer(SCpnt);
733    host->dma.xfer_setup = 0;
734    host->dma.xfer_required = 0;
735    host->dma.xfer_done = 0;
736
737#if (DEBUG & (DEBUG_ABORT|DEBUG_CONNECT))
738    DBG(SCpnt,printk("scsi%d.%c: starting cmd %02X\n",
739	    host->host->host_no, '0' + SCpnt->device->id,
740	    SCpnt->cmnd[0]));
741#endif
742
743    if (from_queue) {
744	    set_bit(SCpnt->device->id * 8 +
745		    (u8)(SCpnt->device->lun & 0x07), host->busyluns);
746
747	host->stats.removes += 1;
748
749	switch (acornscsi_cmdtype(SCpnt->cmnd[0])) {
750	case CMD_WRITE:
751	    host->stats.writes += 1;
752	    break;
753	case CMD_READ:
754	    host->stats.reads += 1;
755	    break;
756	case CMD_MISC:
757	    host->stats.miscs += 1;
758	    break;
759	}
760    }
761
762    return INTR_PROCESSING;
763}
764
765/*
766 * Function: void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp, unsigned int result)
767 * Purpose : complete processing for command
768 * Params  : host   - interface that completed
769 *	     result - driver byte of result
770 */
771static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
772			   unsigned int result)
773{
774	struct scsi_cmnd *SCpnt = *SCpntp;
775
776    /* clean up */
777    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
778
779    host->stats.fins += 1;
780
781    if (SCpnt) {
782	*SCpntp = NULL;
783
784	acornscsi_dma_cleanup(host);
785
786	set_host_byte(SCpnt, result);
787	if (result == DID_OK)
788		scsi_msg_to_host_byte(SCpnt, host->scsi.SCp.Message);
789	set_status_byte(SCpnt, host->scsi.SCp.Status);
790
791	/*
792	 * In theory, this should not happen.  In practice, it seems to.
793	 * Only trigger an error if the device attempts to report all happy
794	 * but with untransferred buffers...  If we don't do something, then
795	 * data loss will occur.  Should we check SCpnt->underflow here?
796	 * It doesn't appear to be set to something meaningful by the higher
797	 * levels all the time.
798	 */
799	if (result == DID_OK) {
800		int xfer_warn = 0;
801
802		if (SCpnt->underflow == 0) {
803			if (host->scsi.SCp.ptr &&
804			    acornscsi_cmdtype(SCpnt->cmnd[0]) != CMD_MISC)
805				xfer_warn = 1;
806		} else {
807			if (host->scsi.SCp.scsi_xferred < SCpnt->underflow ||
808			    host->scsi.SCp.scsi_xferred != host->dma.transferred)
809				xfer_warn = 1;
810		}
811
812		/* ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.6)
813		 *  Targets which break data transfers into multiple
814		 *  connections shall end each successful connection
815		 *  (except possibly the last) with a SAVE DATA
816		 *  POINTER - DISCONNECT message sequence.
817		 *
818		 * This makes it difficult to ensure that a transfer has
819		 * completed.  If we reach the end of a transfer during
820		 * the command, then we can only have finished the transfer.
821		 * therefore, if we seem to have some data remaining, this
822		 * is not a problem.
823		 */
824		if (host->dma.xfer_done)
825			xfer_warn = 0;
826
827		if (xfer_warn) {
828		    switch (get_status_byte(SCpnt)) {
829		    case SAM_STAT_CHECK_CONDITION:
830		    case SAM_STAT_COMMAND_TERMINATED:
831		    case SAM_STAT_BUSY:
832		    case SAM_STAT_TASK_SET_FULL:
833		    case SAM_STAT_RESERVATION_CONFLICT:
834			break;
835
836		    default:
837			scmd_printk(KERN_ERR, SCpnt,
838				    "incomplete data transfer detected: "
839				    "result=%08X", SCpnt->result);
840			scsi_print_command(SCpnt);
841			acornscsi_dumpdma(host, "done");
842			acornscsi_dumplog(host, SCpnt->device->id);
843			set_host_byte(SCpnt, DID_ERROR);
844		    }
845		}
846	}
847
848	clear_bit(SCpnt->device->id * 8 +
849		  (u8)(SCpnt->device->lun & 0x7), host->busyluns);
850
851	scsi_done(SCpnt);
852    } else
853	printk("scsi%d: null command in acornscsi_done", host->host->host_no);
854
855    host->scsi.phase = PHASE_IDLE;
856}
857
858/* ====================================================================================
859 * DMA routines
860 */
861/*
862 * Purpose  : update SCSI Data Pointer
863 * Notes    : this will only be one SG entry or less
864 */
865static
866void acornscsi_data_updateptr(AS_Host *host, struct scsi_pointer *SCp, unsigned int length)
867{
868    SCp->ptr += length;
869    SCp->this_residual -= length;
870
871    if (SCp->this_residual == 0 && next_SCp(SCp) == 0)
872	host->dma.xfer_done = 1;
873}
874
875/*
876 * Prototype: void acornscsi_data_read(AS_Host *host, char *ptr,
877 *				unsigned int start_addr, unsigned int length)
878 * Purpose  : read data from DMA RAM
879 * Params   : host - host to transfer from
880 *	      ptr  - DRAM address
881 *	      start_addr - host mem address
882 *	      length - number of bytes to transfer
883 * Notes    : this will only be one SG entry or less
884 */
885static
886void acornscsi_data_read(AS_Host *host, char *ptr,
887				 unsigned int start_addr, unsigned int length)
888{
889    extern void __acornscsi_in(void __iomem *, char *buf, int len);
890    unsigned int page, offset, len = length;
891
892    page = (start_addr >> 12);
893    offset = start_addr & ((1 << 12) - 1);
894
895    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
896
897    while (len > 0) {
898	unsigned int this_len;
899
900	if (len + offset > (1 << 12))
901	    this_len = (1 << 12) - offset;
902	else
903	    this_len = len;
904
905	__acornscsi_in(host->base + (offset << 1), ptr, this_len);
906
907	offset += this_len;
908	ptr += this_len;
909	len -= this_len;
910
911	if (offset == (1 << 12)) {
912	    offset = 0;
913	    page ++;
914	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
915	}
916    }
917    writeb(host->card.page_reg, host->fast + PAGE_REG);
918}
919
920/*
921 * Prototype: void acornscsi_data_write(AS_Host *host, char *ptr,
922 *				unsigned int start_addr, unsigned int length)
923 * Purpose  : write data to DMA RAM
924 * Params   : host - host to transfer from
925 *	      ptr  - DRAM address
926 *	      start_addr - host mem address
927 *	      length - number of bytes to transfer
928 * Notes    : this will only be one SG entry or less
929 */
930static
931void acornscsi_data_write(AS_Host *host, char *ptr,
932				 unsigned int start_addr, unsigned int length)
933{
934    extern void __acornscsi_out(void __iomem *, char *buf, int len);
935    unsigned int page, offset, len = length;
936
937    page = (start_addr >> 12);
938    offset = start_addr & ((1 << 12) - 1);
939
940    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
941
942    while (len > 0) {
943	unsigned int this_len;
944
945	if (len + offset > (1 << 12))
946	    this_len = (1 << 12) - offset;
947	else
948	    this_len = len;
949
950	__acornscsi_out(host->base + (offset << 1), ptr, this_len);
951
952	offset += this_len;
953	ptr += this_len;
954	len -= this_len;
955
956	if (offset == (1 << 12)) {
957	    offset = 0;
958	    page ++;
959	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
960	}
961    }
962    writeb(host->card.page_reg, host->fast + PAGE_REG);
963}
964
965/* =========================================================================================
966 * On-board DMA routines
967 */
968#ifdef USE_DMAC
969/*
970 * Prototype: void acornscsi_dmastop(AS_Host *host)
971 * Purpose  : stop all DMA
972 * Params   : host - host on which to stop DMA
973 * Notes    : This is called when leaving DATA IN/OUT phase,
974 *	      or when interface is RESET
975 */
976static inline
977void acornscsi_dma_stop(AS_Host *host)
978{
979    dmac_write(host, DMAC_MASKREG, MASK_ON);
980    dmac_clearintr(host);
981
982#if (DEBUG & DEBUG_DMA)
983    DBG(host->SCpnt, acornscsi_dumpdma(host, "stop"));
984#endif
985}
986
987/*
988 * Function: void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
989 * Purpose : setup DMA controller for data transfer
990 * Params  : host - host to setup
991 *	     direction - data transfer direction
992 * Notes   : This is called when entering DATA I/O phase, not
993 *	     while we're in a DATA I/O phase
994 */
995static
996void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
997{
998    unsigned int address, length, mode;
999
1000    host->dma.direction = direction;
1001
1002    dmac_write(host, DMAC_MASKREG, MASK_ON);
1003
1004    if (direction == DMA_OUT) {
1005#if (DEBUG & DEBUG_NO_WRITE)
1006	if (NO_WRITE & (1 << host->SCpnt->device->id)) {
1007	    printk(KERN_CRIT "scsi%d.%c: I can't handle DMA_OUT!\n",
1008		    host->host->host_no, acornscsi_target(host));
1009	    return;
1010	}
1011#endif
1012	mode = DMAC_WRITE;
1013    } else
1014	mode = DMAC_READ;
1015
1016    /*
1017     * Allocate some buffer space, limited to half the buffer size
1018     */
1019    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1020    if (length) {
1021	host->dma.start_addr = address = host->dma.free_addr;
1022	host->dma.free_addr = (host->dma.free_addr + length) &
1023				(DMAC_BUFFER_SIZE - 1);
1024
1025	/*
1026	 * Transfer data to DMA memory
1027	 */
1028	if (direction == DMA_OUT)
1029	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1030				length);
1031
1032	length -= 1;
1033	dmac_write(host, DMAC_TXCNTLO, length);
1034	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1035	dmac_write(host, DMAC_TXADRLO, address);
1036	dmac_write(host, DMAC_TXADRMD, address >> 8);
1037	dmac_write(host, DMAC_TXADRHI, 0);
1038	dmac_write(host, DMAC_MODECON, mode);
1039	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1040
1041#if (DEBUG & DEBUG_DMA)
1042	DBG(host->SCpnt, acornscsi_dumpdma(host, "strt"));
1043#endif
1044	host->dma.xfer_setup = 1;
1045    }
1046}
1047
1048/*
1049 * Function: void acornscsi_dma_cleanup(AS_Host *host)
1050 * Purpose : ensure that all DMA transfers are up-to-date & host->scsi.SCp is correct
1051 * Params  : host - host to finish
1052 * Notes   : This is called when a command is:
1053 *		terminating, RESTORE_POINTERS, SAVE_POINTERS, DISCONNECT
1054 *	   : This must not return until all transfers are completed.
1055 */
1056static
1057void acornscsi_dma_cleanup(AS_Host *host)
1058{
1059    dmac_write(host, DMAC_MASKREG, MASK_ON);
1060    dmac_clearintr(host);
1061
1062    /*
1063     * Check for a pending transfer
1064     */
1065    if (host->dma.xfer_required) {
1066	host->dma.xfer_required = 0;
1067	if (host->dma.direction == DMA_IN)
1068	    acornscsi_data_read(host, host->dma.xfer_ptr,
1069				 host->dma.xfer_start, host->dma.xfer_length);
1070    }
1071
1072    /*
1073     * Has a transfer been setup?
1074     */
1075    if (host->dma.xfer_setup) {
1076	unsigned int transferred;
1077
1078	host->dma.xfer_setup = 0;
1079
1080#if (DEBUG & DEBUG_DMA)
1081	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupi"));
1082#endif
1083
1084	/*
1085	 * Calculate number of bytes transferred from DMA.
1086	 */
1087	transferred = dmac_address(host) - host->dma.start_addr;
1088	host->dma.transferred += transferred;
1089
1090	if (host->dma.direction == DMA_IN)
1091	    acornscsi_data_read(host, host->scsi.SCp.ptr,
1092				 host->dma.start_addr, transferred);
1093
1094	/*
1095	 * Update SCSI pointers
1096	 */
1097	acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1098#if (DEBUG & DEBUG_DMA)
1099	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupo"));
1100#endif
1101    }
1102}
1103
1104/*
1105 * Function: void acornscsi_dmacintr(AS_Host *host)
1106 * Purpose : handle interrupts from DMAC device
1107 * Params  : host - host to process
1108 * Notes   : If reading, we schedule the read to main memory &
1109 *	     allow the transfer to continue.
1110 *	   : If writing, we fill the onboard DMA memory from main
1111 *	     memory.
1112 *	   : Called whenever DMAC finished it's current transfer.
1113 */
1114static
1115void acornscsi_dma_intr(AS_Host *host)
1116{
1117    unsigned int address, length, transferred;
1118
1119#if (DEBUG & DEBUG_DMA)
1120    DBG(host->SCpnt, acornscsi_dumpdma(host, "inti"));
1121#endif
1122
1123    dmac_write(host, DMAC_MASKREG, MASK_ON);
1124    dmac_clearintr(host);
1125
1126    /*
1127     * Calculate amount transferred via DMA
1128     */
1129    transferred = dmac_address(host) - host->dma.start_addr;
1130    host->dma.transferred += transferred;
1131
1132    /*
1133     * Schedule DMA transfer off board
1134     */
1135    if (host->dma.direction == DMA_IN) {
1136	host->dma.xfer_start = host->dma.start_addr;
1137	host->dma.xfer_length = transferred;
1138	host->dma.xfer_ptr = host->scsi.SCp.ptr;
1139	host->dma.xfer_required = 1;
1140    }
1141
1142    acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1143
1144    /*
1145     * Allocate some buffer space, limited to half the on-board RAM size
1146     */
1147    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1148    if (length) {
1149	host->dma.start_addr = address = host->dma.free_addr;
1150	host->dma.free_addr = (host->dma.free_addr + length) &
1151				(DMAC_BUFFER_SIZE - 1);
1152
1153	/*
1154	 * Transfer data to DMA memory
1155	 */
1156	if (host->dma.direction == DMA_OUT)
1157	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1158				length);
1159
1160	length -= 1;
1161	dmac_write(host, DMAC_TXCNTLO, length);
1162	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1163	dmac_write(host, DMAC_TXADRLO, address);
1164	dmac_write(host, DMAC_TXADRMD, address >> 8);
1165	dmac_write(host, DMAC_TXADRHI, 0);
1166	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1167
1168#if (DEBUG & DEBUG_DMA)
1169	DBG(host->SCpnt, acornscsi_dumpdma(host, "into"));
1170#endif
1171    } else {
1172	host->dma.xfer_setup = 0;
1173#if 0
1174	/*
1175	 * If the interface still wants more, then this is an error.
1176	 * We give it another byte, but we also attempt to raise an
1177	 * attention condition.  We continue giving one byte until
1178	 * the device recognises the attention.
1179	 */
1180	if (dmac_read(host, DMAC_STATUS) & STATUS_RQ0) {
1181	    acornscsi_abortcmd(host);
1182
1183	    dmac_write(host, DMAC_TXCNTLO, 0);
1184	    dmac_write(host, DMAC_TXCNTHI, 0);
1185	    dmac_write(host, DMAC_TXADRLO, 0);
1186	    dmac_write(host, DMAC_TXADRMD, 0);
1187	    dmac_write(host, DMAC_TXADRHI, 0);
1188	    dmac_write(host, DMAC_MASKREG, MASK_OFF);
1189	}
1190#endif
1191    }
1192}
1193
1194/*
1195 * Function: void acornscsi_dma_xfer(AS_Host *host)
1196 * Purpose : transfer data between AcornSCSI and memory
1197 * Params  : host - host to process
1198 */
1199static
1200void acornscsi_dma_xfer(AS_Host *host)
1201{
1202    host->dma.xfer_required = 0;
1203
1204    if (host->dma.direction == DMA_IN)
1205	acornscsi_data_read(host, host->dma.xfer_ptr,
1206				host->dma.xfer_start, host->dma.xfer_length);
1207}
1208
1209/*
1210 * Function: void acornscsi_dma_adjust(AS_Host *host)
1211 * Purpose : adjust DMA pointers & count for bytes transferred to
1212 *	     SBIC but not SCSI bus.
1213 * Params  : host - host to adjust DMA count for
1214 */
1215static
1216void acornscsi_dma_adjust(AS_Host *host)
1217{
1218    if (host->dma.xfer_setup) {
1219	signed long transferred;
1220#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1221	DBG(host->SCpnt, acornscsi_dumpdma(host, "adji"));
1222#endif
1223	/*
1224	 * Calculate correct DMA address - DMA is ahead of SCSI bus while
1225	 * writing.
1226	 *  host->scsi.SCp.scsi_xferred is the number of bytes
1227	 *  actually transferred to/from the SCSI bus.
1228	 *  host->dma.transferred is the number of bytes transferred
1229	 *  over DMA since host->dma.start_addr was last set.
1230	 *
1231	 * real_dma_addr = host->dma.start_addr + host->scsi.SCp.scsi_xferred
1232	 *		   - host->dma.transferred
1233	 */
1234	transferred = host->scsi.SCp.scsi_xferred - host->dma.transferred;
1235	if (transferred < 0)
1236	    printk("scsi%d.%c: Ack! DMA write correction %ld < 0!\n",
1237		    host->host->host_no, acornscsi_target(host), transferred);
1238	else if (transferred == 0)
1239	    host->dma.xfer_setup = 0;
1240	else {
1241	    transferred += host->dma.start_addr;
1242	    dmac_write(host, DMAC_TXADRLO, transferred);
1243	    dmac_write(host, DMAC_TXADRMD, transferred >> 8);
1244	    dmac_write(host, DMAC_TXADRHI, transferred >> 16);
1245#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1246	    DBG(host->SCpnt, acornscsi_dumpdma(host, "adjo"));
1247#endif
1248	}
1249    }
1250}
1251#endif
1252
1253/* =========================================================================================
1254 * Data I/O
1255 */
1256static int
1257acornscsi_write_pio(AS_Host *host, char *bytes, int *ptr, int len, unsigned int max_timeout)
1258{
1259	unsigned int asr, timeout = max_timeout;
1260	int my_ptr = *ptr;
1261
1262	while (my_ptr < len) {
1263		asr = sbic_arm_read(host, SBIC_ASR);
1264
1265		if (asr & ASR_DBR) {
1266			timeout = max_timeout;
1267
1268			sbic_arm_write(host, SBIC_DATA, bytes[my_ptr++]);
1269		} else if (asr & ASR_INT)
1270			break;
1271		else if (--timeout == 0)
1272			break;
1273		udelay(1);
1274	}
1275
1276	*ptr = my_ptr;
1277
1278	return (timeout == 0) ? -1 : 0;
1279}
1280
1281/*
1282 * Function: void acornscsi_sendcommand(AS_Host *host)
1283 * Purpose : send a command to a target
1284 * Params  : host - host which is connected to target
1285 */
1286static void
1287acornscsi_sendcommand(AS_Host *host)
1288{
1289	struct scsi_cmnd *SCpnt = host->SCpnt;
1290
1291    sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1292    sbic_arm_writenext(host, 0);
1293    sbic_arm_writenext(host, SCpnt->cmd_len - host->scsi.SCp.sent_command);
1294
1295    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1296
1297    if (acornscsi_write_pio(host, SCpnt->cmnd,
1298	(int *)&host->scsi.SCp.sent_command, SCpnt->cmd_len, 1000000))
1299	printk("scsi%d: timeout while sending command\n", host->host->host_no);
1300
1301    host->scsi.phase = PHASE_COMMAND;
1302}
1303
1304static
1305void acornscsi_sendmessage(AS_Host *host)
1306{
1307    unsigned int message_length = msgqueue_msglength(&host->scsi.msgs);
1308    unsigned int msgnr;
1309    struct message *msg;
1310
1311#if (DEBUG & DEBUG_MESSAGES)
1312    printk("scsi%d.%c: sending message ",
1313	    host->host->host_no, acornscsi_target(host));
1314#endif
1315
1316    switch (message_length) {
1317    case 0:
1318	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1319
1320	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 1");
1321
1322	sbic_arm_write(host, SBIC_DATA, NOP);
1323
1324	host->scsi.last_message = NOP;
1325#if (DEBUG & DEBUG_MESSAGES)
1326	printk("NOP");
1327#endif
1328	break;
1329
1330    case 1:
1331	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1332	msg = msgqueue_getmsg(&host->scsi.msgs, 0);
1333
1334	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 2");
1335
1336	sbic_arm_write(host, SBIC_DATA, msg->msg[0]);
1337
1338	host->scsi.last_message = msg->msg[0];
1339#if (DEBUG & DEBUG_MESSAGES)
1340	spi_print_msg(msg->msg);
1341#endif
1342	break;
1343
1344    default:
1345	/*
1346	 * ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.14)
1347	 * 'When a target sends this (MESSAGE_REJECT) message, it
1348	 *  shall change to MESSAGE IN phase and send this message
1349	 *  prior to requesting additional message bytes from the
1350	 *  initiator.  This provides an interlock so that the
1351	 *  initiator can determine which message byte is rejected.
1352	 */
1353	sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1354	sbic_arm_writenext(host, 0);
1355	sbic_arm_writenext(host, message_length);
1356	acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1357
1358	msgnr = 0;
1359	while ((msg = msgqueue_getmsg(&host->scsi.msgs, msgnr++)) != NULL) {
1360	    unsigned int i;
1361#if (DEBUG & DEBUG_MESSAGES)
1362	    spi_print_msg(msg);
1363#endif
1364	    i = 0;
1365	    if (acornscsi_write_pio(host, msg->msg, &i, msg->length, 1000000))
1366		printk("scsi%d: timeout while sending message\n", host->host->host_no);
1367
1368	    host->scsi.last_message = msg->msg[0];
1369	    if (msg->msg[0] == EXTENDED_MESSAGE)
1370		host->scsi.last_message |= msg->msg[2] << 8;
1371
1372	    if (i != msg->length)
1373		break;
1374	}
1375	break;
1376    }
1377#if (DEBUG & DEBUG_MESSAGES)
1378    printk("\n");
1379#endif
1380}
1381
1382/*
1383 * Function: void acornscsi_readstatusbyte(AS_Host *host)
1384 * Purpose : Read status byte from connected target
1385 * Params  : host - host connected to target
1386 */
1387static
1388void acornscsi_readstatusbyte(AS_Host *host)
1389{
1390    acornscsi_sbic_issuecmd(host, CMND_XFERINFO|CMND_SBT);
1391    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "reading status byte");
1392    host->scsi.SCp.Status = sbic_arm_read(host, SBIC_DATA);
1393}
1394
1395/*
1396 * Function: unsigned char acornscsi_readmessagebyte(AS_Host *host)
1397 * Purpose : Read one message byte from connected target
1398 * Params  : host - host connected to target
1399 */
1400static
1401unsigned char acornscsi_readmessagebyte(AS_Host *host)
1402{
1403    unsigned char message;
1404
1405    acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1406
1407    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "for message byte");
1408
1409    message = sbic_arm_read(host, SBIC_DATA);
1410
1411    /* wait for MSGIN-XFER-PAUSED */
1412    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after message byte");
1413
1414    sbic_arm_read(host, SBIC_SSR);
1415
1416    return message;
1417}
1418
1419/*
1420 * Function: void acornscsi_message(AS_Host *host)
1421 * Purpose : Read complete message from connected target & action message
1422 * Params  : host - host connected to target
1423 */
1424static
1425void acornscsi_message(AS_Host *host)
1426{
1427    struct scsi_pointer *scsi_pointer;
1428    unsigned char message[16];
1429    unsigned int msgidx = 0, msglen = 1;
1430
1431    do {
1432	message[msgidx] = acornscsi_readmessagebyte(host);
1433
1434	switch (msgidx) {
1435	case 0:
1436	    if (message[0] == EXTENDED_MESSAGE ||
1437		(message[0] >= 0x20 && message[0] <= 0x2f))
1438		msglen = 2;
1439	    break;
1440
1441	case 1:
1442	    if (message[0] == EXTENDED_MESSAGE)
1443		msglen += message[msgidx];
1444	    break;
1445	}
1446	msgidx += 1;
1447	if (msgidx < msglen) {
1448	    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1449
1450	    /* wait for next msg-in */
1451	    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after negate ack");
1452	    sbic_arm_read(host, SBIC_SSR);
1453	}
1454    } while (msgidx < msglen);
1455
1456#if (DEBUG & DEBUG_MESSAGES)
1457    printk("scsi%d.%c: message in: ",
1458	    host->host->host_no, acornscsi_target(host));
1459    spi_print_msg(message);
1460    printk("\n");
1461#endif
1462
1463    if (host->scsi.phase == PHASE_RECONNECTED) {
1464	/*
1465	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1466	 * 'Whenever a target reconnects to an initiator to continue
1467	 *  a tagged I/O process, the SIMPLE QUEUE TAG message shall
1468	 *  be sent immediately following the IDENTIFY message...'
1469	 */
1470	if (message[0] == SIMPLE_QUEUE_TAG)
1471	    host->scsi.reconnected.tag = message[1];
1472	if (acornscsi_reconnect_finish(host))
1473	    host->scsi.phase = PHASE_MSGIN;
1474    }
1475
1476    switch (message[0]) {
1477    case ABORT_TASK_SET:
1478    case ABORT_TASK:
1479    case COMMAND_COMPLETE:
1480	if (host->scsi.phase != PHASE_STATUSIN) {
1481	    printk(KERN_ERR "scsi%d.%c: command complete following non-status in phase?\n",
1482		    host->host->host_no, acornscsi_target(host));
1483	    acornscsi_dumplog(host, host->SCpnt->device->id);
1484	}
1485	host->scsi.phase = PHASE_DONE;
1486	host->scsi.SCp.Message = message[0];
1487	break;
1488
1489    case SAVE_POINTERS:
1490	/*
1491	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.20)
1492	 * 'The SAVE DATA POINTER message is sent from a target to
1493	 *  direct the initiator to copy the active data pointer to
1494	 *  the saved data pointer for the current I/O process.
1495	 */
1496	acornscsi_dma_cleanup(host);
1497	scsi_pointer = arm_scsi_pointer(host->SCpnt);
1498	*scsi_pointer = host->scsi.SCp;
1499	scsi_pointer->sent_command = 0;
1500	host->scsi.phase = PHASE_MSGIN;
1501	break;
1502
1503    case RESTORE_POINTERS:
1504	/*
1505	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.19)
1506	 * 'The RESTORE POINTERS message is sent from a target to
1507	 *  direct the initiator to copy the most recently saved
1508	 *  command, data, and status pointers for the I/O process
1509	 *  to the corresponding active pointers.  The command and
1510	 *  status pointers shall be restored to the beginning of
1511	 *  the present command and status areas.'
1512	 */
1513	acornscsi_dma_cleanup(host);
1514	host->scsi.SCp = *arm_scsi_pointer(host->SCpnt);
1515	host->scsi.phase = PHASE_MSGIN;
1516	break;
1517
1518    case DISCONNECT:
1519	/*
1520	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 6.4.2)
1521	 * 'On those occasions when an error or exception condition occurs
1522	 *  and the target elects to repeat the information transfer, the
1523	 *  target may repeat the transfer either issuing a RESTORE POINTERS
1524	 *  message or by disconnecting without issuing a SAVE POINTERS
1525	 *  message.  When reconnection is completed, the most recent
1526	 *  saved pointer values are restored.'
1527	 */
1528	acornscsi_dma_cleanup(host);
1529	host->scsi.phase = PHASE_DISCONNECT;
1530	break;
1531
1532    case MESSAGE_REJECT:
1533#if 0 /* this isn't needed any more */
1534	/*
1535	 * If we were negociating sync transfer, we don't yet know if
1536	 * this REJECT is for the sync transfer or for the tagged queue/wide
1537	 * transfer.  Re-initiate sync transfer negotiation now, and if
1538	 * we got a REJECT in response to SDTR, then it'll be set to DONE.
1539	 */
1540	if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST)
1541	    host->device[host->SCpnt->device->id].sync_state = SYNC_NEGOCIATE;
1542#endif
1543
1544	/*
1545	 * If we have any messages waiting to go out, then assert ATN now
1546	 */
1547	if (msgqueue_msglength(&host->scsi.msgs))
1548	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1549
1550	switch (host->scsi.last_message) {
1551	case EXTENDED_MESSAGE | (EXTENDED_SDTR << 8):
1552	    /*
1553	     * Target can't handle synchronous transfers
1554	     */
1555	    printk(KERN_NOTICE "scsi%d.%c: Using asynchronous transfer\n",
1556		    host->host->host_no, acornscsi_target(host));
1557	    host->device[host->SCpnt->device->id].sync_xfer = SYNCHTRANSFER_2DBA;
1558	    host->device[host->SCpnt->device->id].sync_state = SYNC_ASYNCHRONOUS;
1559	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1560	    break;
1561
1562	default:
1563	    break;
1564	}
1565	break;
1566
1567    case SIMPLE_QUEUE_TAG:
1568	/* tag queue reconnect... message[1] = queue tag.  Print something to indicate something happened! */
1569	printk("scsi%d.%c: reconnect queue tag %02X\n",
1570		host->host->host_no, acornscsi_target(host),
1571		message[1]);
1572	break;
1573
1574    case EXTENDED_MESSAGE:
1575	switch (message[2]) {
1576#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1577	case EXTENDED_SDTR:
1578	    if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST) {
1579		/*
1580		 * We requested synchronous transfers.  This isn't quite right...
1581		 * We can only say if this succeeded if we proceed on to execute the
1582		 * command from this message.  If we get a MESSAGE PARITY ERROR,
1583		 * and the target retries fail, then we fallback to asynchronous mode
1584		 */
1585		host->device[host->SCpnt->device->id].sync_state = SYNC_COMPLETED;
1586		printk(KERN_NOTICE "scsi%d.%c: Using synchronous transfer, offset %d, %d ns\n",
1587			host->host->host_no, acornscsi_target(host),
1588			message[4], message[3] * 4);
1589		host->device[host->SCpnt->device->id].sync_xfer =
1590			calc_sync_xfer(message[3] * 4, message[4]);
1591	    } else {
1592		unsigned char period, length;
1593		/*
1594		 * Target requested synchronous transfers.  The agreement is only
1595		 * to be in operation AFTER the target leaves message out phase.
1596		 */
1597		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1598		period = max_t(unsigned int, message[3], sdtr_period / 4);
1599		length = min_t(unsigned int, message[4], sdtr_size);
1600		msgqueue_addmsg(&host->scsi.msgs, 5, EXTENDED_MESSAGE, 3,
1601				 EXTENDED_SDTR, period, length);
1602		host->device[host->SCpnt->device->id].sync_xfer =
1603			calc_sync_xfer(period * 4, length);
1604	    }
1605	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1606	    break;
1607#else
1608	    /* We do not accept synchronous transfers.  Respond with a
1609	     * MESSAGE_REJECT.
1610	     */
1611#endif
1612
1613	case EXTENDED_WDTR:
1614	    /* The WD33C93A is only 8-bit.  We respond with a MESSAGE_REJECT
1615	     * to a wide data transfer request.
1616	     */
1617	default:
1618	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1619	    msgqueue_flush(&host->scsi.msgs);
1620	    msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1621	    break;
1622	}
1623	break;
1624
1625    default: /* reject message */
1626	printk(KERN_ERR "scsi%d.%c: unrecognised message %02X, rejecting\n",
1627		host->host->host_no, acornscsi_target(host),
1628		message[0]);
1629	acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1630	msgqueue_flush(&host->scsi.msgs);
1631	msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1632	host->scsi.phase = PHASE_MSGIN;
1633	break;
1634    }
1635    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1636}
1637
1638/*
1639 * Function: int acornscsi_buildmessages(AS_Host *host)
1640 * Purpose : build the connection messages for a host
1641 * Params  : host - host to add messages to
1642 */
1643static
1644void acornscsi_buildmessages(AS_Host *host)
1645{
1646#if 0
1647    /* does the device need resetting? */
1648    if (cmd_reset) {
1649	msgqueue_addmsg(&host->scsi.msgs, 1, BUS_DEVICE_RESET);
1650	return;
1651    }
1652#endif
1653
1654    msgqueue_addmsg(&host->scsi.msgs, 1,
1655		     IDENTIFY(host->device[host->SCpnt->device->id].disconnect_ok,
1656			     host->SCpnt->device->lun));
1657
1658#if 0
1659    /* does the device need the current command aborted */
1660    if (cmd_aborted) {
1661	acornscsi_abortcmd(host);
1662	return;
1663    }
1664#endif
1665
1666
1667#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1668    if (host->device[host->SCpnt->device->id].sync_state == SYNC_NEGOCIATE) {
1669	host->device[host->SCpnt->device->id].sync_state = SYNC_SENT_REQUEST;
1670	msgqueue_addmsg(&host->scsi.msgs, 5,
1671			 EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
1672			 sdtr_period / 4, sdtr_size);
1673    }
1674#endif
1675}
1676
1677/*
1678 * Function: int acornscsi_starttransfer(AS_Host *host)
1679 * Purpose : transfer data to/from connected target
1680 * Params  : host - host to which target is connected
1681 * Returns : 0 if failure
1682 */
1683static
1684int acornscsi_starttransfer(AS_Host *host)
1685{
1686    int residual;
1687
1688    if (!host->scsi.SCp.ptr /*&& host->scsi.SCp.this_residual*/) {
1689	printk(KERN_ERR "scsi%d.%c: null buffer passed to acornscsi_starttransfer\n",
1690		host->host->host_no, acornscsi_target(host));
1691	return 0;
1692    }
1693
1694    residual = scsi_bufflen(host->SCpnt) - host->scsi.SCp.scsi_xferred;
1695
1696    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1697    sbic_arm_writenext(host, residual >> 16);
1698    sbic_arm_writenext(host, residual >> 8);
1699    sbic_arm_writenext(host, residual);
1700    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1701    return 1;
1702}
1703
1704/* =========================================================================================
1705 * Connection & Disconnection
1706 */
1707/*
1708 * Function : acornscsi_reconnect(AS_Host *host)
1709 * Purpose  : reconnect a previously disconnected command
1710 * Params   : host - host specific data
1711 * Remarks  : SCSI spec says:
1712 *		'The set of active pointers is restored from the set
1713 *		 of saved pointers upon reconnection of the I/O process'
1714 */
1715static
1716int acornscsi_reconnect(AS_Host *host)
1717{
1718    unsigned int target, lun, ok = 0;
1719
1720    target = sbic_arm_read(host, SBIC_SOURCEID);
1721
1722    if (!(target & 8))
1723	printk(KERN_ERR "scsi%d: invalid source id after reselection "
1724		"- device fault?\n",
1725		host->host->host_no);
1726
1727    target &= 7;
1728
1729    if (host->SCpnt && !host->scsi.disconnectable) {
1730	printk(KERN_ERR "scsi%d.%d: reconnected while command in "
1731		"progress to target %d?\n",
1732		host->host->host_no, target, host->SCpnt->device->id);
1733	host->SCpnt = NULL;
1734    }
1735
1736    lun = sbic_arm_read(host, SBIC_DATA) & 7;
1737
1738    host->scsi.reconnected.target = target;
1739    host->scsi.reconnected.lun = lun;
1740    host->scsi.reconnected.tag = 0;
1741
1742    if (host->scsi.disconnectable && host->SCpnt &&
1743	host->SCpnt->device->id == target && host->SCpnt->device->lun == lun)
1744	ok = 1;
1745
1746    if (!ok && queue_probetgtlun(&host->queues.disconnected, target, lun))
1747	ok = 1;
1748
1749    ADD_STATUS(target, 0x81, host->scsi.phase, 0);
1750
1751    if (ok) {
1752	host->scsi.phase = PHASE_RECONNECTED;
1753    } else {
1754	/* this doesn't seem to work */
1755	printk(KERN_ERR "scsi%d.%c: reselected with no command "
1756		"to reconnect with\n",
1757		host->host->host_no, '0' + target);
1758	acornscsi_dumplog(host, target);
1759	acornscsi_abortcmd(host);
1760	if (host->SCpnt) {
1761	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1762	    host->SCpnt = NULL;
1763	}
1764    }
1765    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1766    return !ok;
1767}
1768
1769/*
1770 * Function: int acornscsi_reconnect_finish(AS_Host *host)
1771 * Purpose : finish reconnecting a command
1772 * Params  : host - host to complete
1773 * Returns : 0 if failed
1774 */
1775static
1776int acornscsi_reconnect_finish(AS_Host *host)
1777{
1778    if (host->scsi.disconnectable && host->SCpnt) {
1779	host->scsi.disconnectable = 0;
1780	if (host->SCpnt->device->id  == host->scsi.reconnected.target &&
1781	    host->SCpnt->device->lun == host->scsi.reconnected.lun &&
1782	    scsi_cmd_to_rq(host->SCpnt)->tag == host->scsi.reconnected.tag) {
1783#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1784	    DBG(host->SCpnt, printk("scsi%d.%c: reconnected",
1785		    host->host->host_no, acornscsi_target(host)));
1786#endif
1787	} else {
1788	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1789#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1790	    DBG(host->SCpnt, printk("scsi%d.%c: had to move command "
1791		    "to disconnected queue\n",
1792		    host->host->host_no, acornscsi_target(host)));
1793#endif
1794	    host->SCpnt = NULL;
1795	}
1796    }
1797    if (!host->SCpnt) {
1798	host->SCpnt = queue_remove_tgtluntag(&host->queues.disconnected,
1799				host->scsi.reconnected.target,
1800				host->scsi.reconnected.lun,
1801				host->scsi.reconnected.tag);
1802#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1803	DBG(host->SCpnt, printk("scsi%d.%c: had to get command",
1804		host->host->host_no, acornscsi_target(host)));
1805#endif
1806    }
1807
1808    if (!host->SCpnt)
1809	acornscsi_abortcmd(host);
1810    else {
1811	/*
1812	 * Restore data pointer from SAVED pointers.
1813	 */
1814	host->scsi.SCp = *arm_scsi_pointer(host->SCpnt);
1815#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1816	printk(", data pointers: [%p, %X]",
1817		host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
1818#endif
1819    }
1820#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1821    printk("\n");
1822#endif
1823
1824    host->dma.transferred = host->scsi.SCp.scsi_xferred;
1825
1826    return host->SCpnt != NULL;
1827}
1828
1829/*
1830 * Function: void acornscsi_disconnect_unexpected(AS_Host *host)
1831 * Purpose : handle an unexpected disconnect
1832 * Params  : host - host on which disconnect occurred
1833 */
1834static
1835void acornscsi_disconnect_unexpected(AS_Host *host)
1836{
1837    printk(KERN_ERR "scsi%d.%c: unexpected disconnect\n",
1838	    host->host->host_no, acornscsi_target(host));
1839#if (DEBUG & DEBUG_ABORT)
1840    acornscsi_dumplog(host, 8);
1841#endif
1842
1843    acornscsi_done(host, &host->SCpnt, DID_ERROR);
1844}
1845
1846/*
1847 * Function: void acornscsi_abortcmd(AS_host *host, unsigned char tag)
1848 * Purpose : abort a currently executing command
1849 * Params  : host - host with connected command to abort
1850 */
1851static
1852void acornscsi_abortcmd(AS_Host *host)
1853{
1854    host->scsi.phase = PHASE_ABORTED;
1855    sbic_arm_write(host, SBIC_CMND, CMND_ASSERTATN);
1856
1857    msgqueue_flush(&host->scsi.msgs);
1858    msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1859}
1860
1861/* ==========================================================================================
1862 * Interrupt routines.
1863 */
1864/*
1865 * Function: int acornscsi_sbicintr(AS_Host *host)
1866 * Purpose : handle interrupts from SCSI device
1867 * Params  : host - host to process
1868 * Returns : INTR_PROCESS if expecting another SBIC interrupt
1869 *	     INTR_IDLE if no interrupt
1870 *	     INTR_NEXT_COMMAND if we have finished processing the command
1871 */
1872static
1873intr_ret_t acornscsi_sbicintr(AS_Host *host, int in_irq)
1874{
1875    unsigned int asr, ssr;
1876
1877    asr = sbic_arm_read(host, SBIC_ASR);
1878    if (!(asr & ASR_INT))
1879	return INTR_IDLE;
1880
1881    ssr = sbic_arm_read(host, SBIC_SSR);
1882
1883#if (DEBUG & DEBUG_PHASES)
1884    print_sbic_status(asr, ssr, host->scsi.phase);
1885#endif
1886
1887    ADD_STATUS(8, ssr, host->scsi.phase, in_irq);
1888
1889    if (host->SCpnt && !host->scsi.disconnectable)
1890	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
1891
1892    switch (ssr) {
1893    case 0x00:				/* reset state - not advanced			*/
1894	printk(KERN_ERR "scsi%d: reset in standard mode but wanted advanced mode.\n",
1895		host->host->host_no);
1896	/* setup sbic - WD33C93A */
1897	sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
1898	sbic_arm_write(host, SBIC_CMND, CMND_RESET);
1899	return INTR_IDLE;
1900
1901    case 0x01:				/* reset state - advanced			*/
1902	sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
1903	sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
1904	sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
1905	sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
1906	msgqueue_flush(&host->scsi.msgs);
1907	return INTR_IDLE;
1908
1909    case 0x41:				/* unexpected disconnect aborted command	*/
1910	acornscsi_disconnect_unexpected(host);
1911	return INTR_NEXT_COMMAND;
1912    }
1913
1914    switch (host->scsi.phase) {
1915    case PHASE_CONNECTING:		/* STATE: command removed from issue queue	*/
1916	switch (ssr) {
1917	case 0x11:			/* -> PHASE_CONNECTED				*/
1918	    /* BUS FREE -> SELECTION */
1919	    host->scsi.phase = PHASE_CONNECTED;
1920	    msgqueue_flush(&host->scsi.msgs);
1921	    host->dma.transferred = host->scsi.SCp.scsi_xferred;
1922	    /* 33C93 gives next interrupt indicating bus phase */
1923	    asr = sbic_arm_read(host, SBIC_ASR);
1924	    if (!(asr & ASR_INT))
1925		break;
1926	    ssr = sbic_arm_read(host, SBIC_SSR);
1927	    ADD_STATUS(8, ssr, host->scsi.phase, 1);
1928	    ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, 1);
1929	    goto connected;
1930
1931	case 0x42:			/* select timed out				*/
1932					/* -> PHASE_IDLE				*/
1933	    acornscsi_done(host, &host->SCpnt, DID_NO_CONNECT);
1934	    return INTR_NEXT_COMMAND;
1935
1936	case 0x81:			/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
1937	    /* BUS FREE -> RESELECTION */
1938	    host->origSCpnt = host->SCpnt;
1939	    host->SCpnt = NULL;
1940	    msgqueue_flush(&host->scsi.msgs);
1941	    acornscsi_reconnect(host);
1942	    break;
1943
1944	default:
1945	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTING, SSR %02X?\n",
1946		    host->host->host_no, acornscsi_target(host), ssr);
1947	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
1948	    acornscsi_abortcmd(host);
1949	}
1950	return INTR_PROCESSING;
1951
1952    connected:
1953    case PHASE_CONNECTED:		/* STATE: device selected ok			*/
1954	switch (ssr) {
1955#ifdef NONSTANDARD
1956	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
1957	    /* SELECTION -> COMMAND */
1958	    acornscsi_sendcommand(host);
1959	    break;
1960
1961	case 0x8b:			/* -> PHASE_STATUS				*/
1962	    /* SELECTION -> STATUS */
1963	    acornscsi_readstatusbyte(host);
1964	    host->scsi.phase = PHASE_STATUSIN;
1965	    break;
1966#endif
1967
1968	case 0x8e:			/* -> PHASE_MSGOUT				*/
1969	    /* SELECTION ->MESSAGE OUT */
1970	    host->scsi.phase = PHASE_MSGOUT;
1971	    acornscsi_buildmessages(host);
1972	    acornscsi_sendmessage(host);
1973	    break;
1974
1975	/* these should not happen */
1976	case 0x85:			/* target disconnected				*/
1977	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
1978	    break;
1979
1980	default:
1981	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTED, SSR %02X?\n",
1982		    host->host->host_no, acornscsi_target(host), ssr);
1983	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
1984	    acornscsi_abortcmd(host);
1985	}
1986	return INTR_PROCESSING;
1987
1988    case PHASE_MSGOUT:			/* STATE: connected & sent IDENTIFY message	*/
1989	/*
1990	 * SCSI standard says that MESSAGE OUT phases can be followed by a
1991	 * DATA phase, STATUS phase, MESSAGE IN phase or COMMAND phase
1992	 */
1993	switch (ssr) {
1994	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
1995	case 0x1a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
1996	    /* MESSAGE OUT -> COMMAND */
1997	    acornscsi_sendcommand(host);
1998	    break;
1999
2000	case 0x8b:			/* -> PHASE_STATUS				*/
2001	case 0x1b:			/* -> PHASE_STATUS				*/
2002	    /* MESSAGE OUT -> STATUS */
2003	    acornscsi_readstatusbyte(host);
2004	    host->scsi.phase = PHASE_STATUSIN;
2005	    break;
2006
2007	case 0x8e:			/* -> PHASE_MSGOUT				*/
2008	    /* MESSAGE_OUT(MESSAGE_IN) ->MESSAGE OUT */
2009	    acornscsi_sendmessage(host);
2010	    break;
2011
2012	case 0x4f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2013	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2014	    /* MESSAGE OUT -> MESSAGE IN */
2015	    acornscsi_message(host);
2016	    break;
2017
2018	default:
2019	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGOUT, SSR %02X?\n",
2020		    host->host->host_no, acornscsi_target(host), ssr);
2021	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2022	}
2023	return INTR_PROCESSING;
2024
2025    case PHASE_COMMAND: 		/* STATE: connected & command sent		*/
2026	switch (ssr) {
2027	case 0x18:			/* -> PHASE_DATAOUT				*/
2028	    /* COMMAND -> DATA OUT */
2029	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2030		acornscsi_abortcmd(host);
2031	    acornscsi_dma_setup(host, DMA_OUT);
2032	    if (!acornscsi_starttransfer(host))
2033		acornscsi_abortcmd(host);
2034	    host->scsi.phase = PHASE_DATAOUT;
2035	    return INTR_IDLE;
2036
2037	case 0x19:			/* -> PHASE_DATAIN				*/
2038	    /* COMMAND -> DATA IN */
2039	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2040		acornscsi_abortcmd(host);
2041	    acornscsi_dma_setup(host, DMA_IN);
2042	    if (!acornscsi_starttransfer(host))
2043		acornscsi_abortcmd(host);
2044	    host->scsi.phase = PHASE_DATAIN;
2045	    return INTR_IDLE;
2046
2047	case 0x1b:			/* -> PHASE_STATUS				*/
2048	    /* COMMAND -> STATUS */
2049	    acornscsi_readstatusbyte(host);
2050	    host->scsi.phase = PHASE_STATUSIN;
2051	    break;
2052
2053	case 0x1e:			/* -> PHASE_MSGOUT				*/
2054	    /* COMMAND -> MESSAGE OUT */
2055	    acornscsi_sendmessage(host);
2056	    break;
2057
2058	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2059	    /* COMMAND -> MESSAGE IN */
2060	    acornscsi_message(host);
2061	    break;
2062
2063	default:
2064	    printk(KERN_ERR "scsi%d.%c: PHASE_COMMAND, SSR %02X?\n",
2065		    host->host->host_no, acornscsi_target(host), ssr);
2066	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2067	}
2068	return INTR_PROCESSING;
2069
2070    case PHASE_DISCONNECT:		/* STATE: connected, received DISCONNECT msg	*/
2071	if (ssr == 0x85) {		/* -> PHASE_IDLE				*/
2072	    host->scsi.disconnectable = 1;
2073	    host->scsi.reconnected.tag = 0;
2074	    host->scsi.phase = PHASE_IDLE;
2075	    host->stats.disconnects += 1;
2076	} else {
2077	    printk(KERN_ERR "scsi%d.%c: PHASE_DISCONNECT, SSR %02X instead of disconnect?\n",
2078		    host->host->host_no, acornscsi_target(host), ssr);
2079	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2080	}
2081	return INTR_NEXT_COMMAND;
2082
2083    case PHASE_IDLE:			/* STATE: disconnected				*/
2084	if (ssr == 0x81)		/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2085	    acornscsi_reconnect(host);
2086	else {
2087	    printk(KERN_ERR "scsi%d.%c: PHASE_IDLE, SSR %02X while idle?\n",
2088		    host->host->host_no, acornscsi_target(host), ssr);
2089	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2090	}
2091	return INTR_PROCESSING;
2092
2093    case PHASE_RECONNECTED:		/* STATE: device reconnected to initiator	*/
2094	/*
2095	 * Command reconnected - if MESGIN, get message - it may be
2096	 * the tag.  If not, get command out of disconnected queue
2097	 */
2098	/*
2099	 * If we reconnected and we're not in MESSAGE IN phase after IDENTIFY,
2100	 * reconnect I_T_L command
2101	 */
2102	if (ssr != 0x8f && !acornscsi_reconnect_finish(host))
2103	    return INTR_IDLE;
2104	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
2105	switch (ssr) {
2106	case 0x88:			/* data out phase				*/
2107					/* -> PHASE_DATAOUT				*/
2108	    /* MESSAGE IN -> DATA OUT */
2109	    acornscsi_dma_setup(host, DMA_OUT);
2110	    if (!acornscsi_starttransfer(host))
2111		acornscsi_abortcmd(host);
2112	    host->scsi.phase = PHASE_DATAOUT;
2113	    return INTR_IDLE;
2114
2115	case 0x89:			/* data in phase				*/
2116					/* -> PHASE_DATAIN				*/
2117	    /* MESSAGE IN -> DATA IN */
2118	    acornscsi_dma_setup(host, DMA_IN);
2119	    if (!acornscsi_starttransfer(host))
2120		acornscsi_abortcmd(host);
2121	    host->scsi.phase = PHASE_DATAIN;
2122	    return INTR_IDLE;
2123
2124	case 0x8a:			/* command out					*/
2125	    /* MESSAGE IN -> COMMAND */
2126	    acornscsi_sendcommand(host);/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2127	    break;
2128
2129	case 0x8b:			/* status in					*/
2130					/* -> PHASE_STATUSIN				*/
2131	    /* MESSAGE IN -> STATUS */
2132	    acornscsi_readstatusbyte(host);
2133	    host->scsi.phase = PHASE_STATUSIN;
2134	    break;
2135
2136	case 0x8e:			/* message out					*/
2137					/* -> PHASE_MSGOUT				*/
2138	    /* MESSAGE IN -> MESSAGE OUT */
2139	    acornscsi_sendmessage(host);
2140	    break;
2141
2142	case 0x8f:			/* message in					*/
2143	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2144	    break;
2145
2146	default:
2147	    printk(KERN_ERR "scsi%d.%c: PHASE_RECONNECTED, SSR %02X after reconnect?\n",
2148		    host->host->host_no, acornscsi_target(host), ssr);
2149	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2150	}
2151	return INTR_PROCESSING;
2152
2153    case PHASE_DATAIN:			/* STATE: transferred data in			*/
2154	/*
2155	 * This is simple - if we disconnect then the DMA address & count is
2156	 * correct.
2157	 */
2158	switch (ssr) {
2159	case 0x19:			/* -> PHASE_DATAIN				*/
2160	case 0x89:			/* -> PHASE_DATAIN				*/
2161	    acornscsi_abortcmd(host);
2162	    return INTR_IDLE;
2163
2164	case 0x1b:			/* -> PHASE_STATUSIN				*/
2165	case 0x4b:			/* -> PHASE_STATUSIN				*/
2166	case 0x8b:			/* -> PHASE_STATUSIN				*/
2167	    /* DATA IN -> STATUS */
2168	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2169					  acornscsi_sbic_xfcount(host);
2170	    acornscsi_dma_stop(host);
2171	    acornscsi_readstatusbyte(host);
2172	    host->scsi.phase = PHASE_STATUSIN;
2173	    break;
2174
2175	case 0x1e:			/* -> PHASE_MSGOUT				*/
2176	case 0x4e:			/* -> PHASE_MSGOUT				*/
2177	case 0x8e:			/* -> PHASE_MSGOUT				*/
2178	    /* DATA IN -> MESSAGE OUT */
2179	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2180					  acornscsi_sbic_xfcount(host);
2181	    acornscsi_dma_stop(host);
2182	    acornscsi_sendmessage(host);
2183	    break;
2184
2185	case 0x1f:			/* message in					*/
2186	case 0x4f:			/* message in					*/
2187	case 0x8f:			/* message in					*/
2188	    /* DATA IN -> MESSAGE IN */
2189	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2190					  acornscsi_sbic_xfcount(host);
2191	    acornscsi_dma_stop(host);
2192	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2193	    break;
2194
2195	default:
2196	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAIN, SSR %02X?\n",
2197		    host->host->host_no, acornscsi_target(host), ssr);
2198	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2199	}
2200	return INTR_PROCESSING;
2201
2202    case PHASE_DATAOUT: 		/* STATE: transferred data out			*/
2203	/*
2204	 * This is more complicated - if we disconnect, the DMA could be 12
2205	 * bytes ahead of us.  We need to correct this.
2206	 */
2207	switch (ssr) {
2208	case 0x18:			/* -> PHASE_DATAOUT				*/
2209	case 0x88:			/* -> PHASE_DATAOUT				*/
2210	    acornscsi_abortcmd(host);
2211	    return INTR_IDLE;
2212
2213	case 0x1b:			/* -> PHASE_STATUSIN				*/
2214	case 0x4b:			/* -> PHASE_STATUSIN				*/
2215	case 0x8b:			/* -> PHASE_STATUSIN				*/
2216	    /* DATA OUT -> STATUS */
2217	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2218					  acornscsi_sbic_xfcount(host);
2219	    acornscsi_dma_stop(host);
2220	    acornscsi_dma_adjust(host);
2221	    acornscsi_readstatusbyte(host);
2222	    host->scsi.phase = PHASE_STATUSIN;
2223	    break;
2224
2225	case 0x1e:			/* -> PHASE_MSGOUT				*/
2226	case 0x4e:			/* -> PHASE_MSGOUT				*/
2227	case 0x8e:			/* -> PHASE_MSGOUT				*/
2228	    /* DATA OUT -> MESSAGE OUT */
2229	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2230					  acornscsi_sbic_xfcount(host);
2231	    acornscsi_dma_stop(host);
2232	    acornscsi_dma_adjust(host);
2233	    acornscsi_sendmessage(host);
2234	    break;
2235
2236	case 0x1f:			/* message in					*/
2237	case 0x4f:			/* message in					*/
2238	case 0x8f:			/* message in					*/
2239	    /* DATA OUT -> MESSAGE IN */
2240	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2241					  acornscsi_sbic_xfcount(host);
2242	    acornscsi_dma_stop(host);
2243	    acornscsi_dma_adjust(host);
2244	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2245	    break;
2246
2247	default:
2248	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAOUT, SSR %02X?\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_STATUSIN:		/* STATE: status in complete			*/
2255	switch (ssr) {
2256	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2257	case 0x8f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2258	    /* STATUS -> MESSAGE IN */
2259	    acornscsi_message(host);
2260	    break;
2261
2262	case 0x1e:			/* -> PHASE_MSGOUT				*/
2263	case 0x8e:			/* -> PHASE_MSGOUT				*/
2264	    /* STATUS -> MESSAGE OUT */
2265	    acornscsi_sendmessage(host);
2266	    break;
2267
2268	default:
2269	    printk(KERN_ERR "scsi%d.%c: PHASE_STATUSIN, SSR %02X instead of MESSAGE_IN?\n",
2270		    host->host->host_no, acornscsi_target(host), ssr);
2271	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2272	}
2273	return INTR_PROCESSING;
2274
2275    case PHASE_MSGIN:			/* STATE: message in				*/
2276	switch (ssr) {
2277	case 0x1e:			/* -> PHASE_MSGOUT				*/
2278	case 0x4e:			/* -> PHASE_MSGOUT				*/
2279	case 0x8e:			/* -> PHASE_MSGOUT				*/
2280	    /* MESSAGE IN -> MESSAGE OUT */
2281	    acornscsi_sendmessage(host);
2282	    break;
2283
2284	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2285	case 0x2f:
2286	case 0x4f:
2287	case 0x8f:
2288	    acornscsi_message(host);
2289	    break;
2290
2291	case 0x85:
2292	    printk("scsi%d.%c: strange message in disconnection\n",
2293		host->host->host_no, acornscsi_target(host));
2294	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2295	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2296	    break;
2297
2298	default:
2299	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGIN, SSR %02X after message in?\n",
2300		    host->host->host_no, acornscsi_target(host), ssr);
2301	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2302	}
2303	return INTR_PROCESSING;
2304
2305    case PHASE_DONE:			/* STATE: received status & message		*/
2306	switch (ssr) {
2307	case 0x85:			/* -> PHASE_IDLE				*/
2308	    acornscsi_done(host, &host->SCpnt, DID_OK);
2309	    return INTR_NEXT_COMMAND;
2310
2311	case 0x1e:
2312	case 0x8e:
2313	    acornscsi_sendmessage(host);
2314	    break;
2315
2316	default:
2317	    printk(KERN_ERR "scsi%d.%c: PHASE_DONE, SSR %02X instead of disconnect?\n",
2318		    host->host->host_no, acornscsi_target(host), ssr);
2319	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2320	}
2321	return INTR_PROCESSING;
2322
2323    case PHASE_ABORTED:
2324	switch (ssr) {
2325	case 0x85:
2326	    if (host->SCpnt)
2327		acornscsi_done(host, &host->SCpnt, DID_ABORT);
2328	    else {
2329		clear_bit(host->scsi.reconnected.target * 8 + host->scsi.reconnected.lun,
2330			  host->busyluns);
2331		host->scsi.phase = PHASE_IDLE;
2332	    }
2333	    return INTR_NEXT_COMMAND;
2334
2335	case 0x1e:
2336	case 0x2e:
2337	case 0x4e:
2338	case 0x8e:
2339	    acornscsi_sendmessage(host);
2340	    break;
2341
2342	default:
2343	    printk(KERN_ERR "scsi%d.%c: PHASE_ABORTED, SSR %02X?\n",
2344		    host->host->host_no, acornscsi_target(host), ssr);
2345	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2346	}
2347	return INTR_PROCESSING;
2348
2349    default:
2350	printk(KERN_ERR "scsi%d.%c: unknown driver phase %d\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
2357/*
2358 * Prototype: void acornscsi_intr(int irq, void *dev_id)
2359 * Purpose  : handle interrupts from Acorn SCSI card
2360 * Params   : irq    - interrupt number
2361 *	      dev_id - device specific data (AS_Host structure)
2362 */
2363static irqreturn_t
2364acornscsi_intr(int irq, void *dev_id)
2365{
2366    AS_Host *host = (AS_Host *)dev_id;
2367    intr_ret_t ret;
2368    int iostatus;
2369    int in_irq = 0;
2370
2371    do {
2372	ret = INTR_IDLE;
2373
2374	iostatus = readb(host->fast + INT_REG);
2375
2376	if (iostatus & 2) {
2377	    acornscsi_dma_intr(host);
2378	    iostatus = readb(host->fast + INT_REG);
2379	}
2380
2381	if (iostatus & 8)
2382	    ret = acornscsi_sbicintr(host, in_irq);
2383
2384	/*
2385	 * If we have a transfer pending, start it.
2386	 * Only start it if the interface has already started transferring
2387	 * it's data
2388	 */
2389	if (host->dma.xfer_required)
2390	    acornscsi_dma_xfer(host);
2391
2392	if (ret == INTR_NEXT_COMMAND)
2393	    ret = acornscsi_kick(host);
2394
2395	in_irq = 1;
2396    } while (ret != INTR_IDLE);
2397
2398    return IRQ_HANDLED;
2399}
2400
2401/*=============================================================================================
2402 * Interfaces between interrupt handler and rest of scsi code
2403 */
2404
2405/*
2406 * Function : acornscsi_queuecmd(struct scsi_cmnd *cmd)
2407 * Purpose  : queues a SCSI command
2408 * Params   : cmd  - SCSI command
2409 * Returns  : 0, or < 0 on error.
2410 */
2411static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt)
2412{
2413    struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
2414    void (*done)(struct scsi_cmnd *) = scsi_done;
2415    AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2416
2417#if (DEBUG & DEBUG_NO_WRITE)
2418    if (acornscsi_cmdtype(SCpnt->cmnd[0]) == CMD_WRITE && (NO_WRITE & (1 << SCpnt->device->id))) {
2419	printk(KERN_CRIT "scsi%d.%c: WRITE attempted with NO_WRITE flag set\n",
2420	    host->host->host_no, '0' + SCpnt->device->id);
2421	set_host_byte(SCpnt, DID_NO_CONNECT);
2422	done(SCpnt);
2423	return 0;
2424    }
2425#endif
2426
2427    SCpnt->host_scribble = NULL;
2428    SCpnt->result = 0;
2429    scsi_pointer->phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
2430    scsi_pointer->sent_command = 0;
2431    scsi_pointer->scsi_xferred = 0;
2432
2433    init_SCp(SCpnt);
2434
2435    host->stats.queues += 1;
2436
2437    {
2438	unsigned long flags;
2439
2440	if (!queue_add_cmd_ordered(&host->queues.issue, SCpnt)) {
2441		set_host_byte(SCpnt, DID_ERROR);
2442	    done(SCpnt);
2443	    return 0;
2444	}
2445	local_irq_save(flags);
2446	if (host->scsi.phase == PHASE_IDLE)
2447	    acornscsi_kick(host);
2448	local_irq_restore(flags);
2449    }
2450    return 0;
2451}
2452
2453DEF_SCSI_QCMD(acornscsi_queuecmd)
2454
2455enum res_abort { res_not_running, res_success, res_success_clear, res_snooze };
2456
2457/*
2458 * Prototype: enum res acornscsi_do_abort(struct scsi_cmnd *SCpnt)
2459 * Purpose  : abort a command on this host
2460 * Params   : SCpnt - command to abort
2461 * Returns  : our abort status
2462 */
2463static enum res_abort acornscsi_do_abort(AS_Host *host, struct scsi_cmnd *SCpnt)
2464{
2465	enum res_abort res = res_not_running;
2466
2467	if (queue_remove_cmd(&host->queues.issue, SCpnt)) {
2468		/*
2469		 * The command was on the issue queue, and has not been
2470		 * issued yet.  We can remove the command from the queue,
2471		 * and acknowledge the abort.  Neither the devices nor the
2472		 * interface know about the command.
2473		 */
2474//#if (DEBUG & DEBUG_ABORT)
2475		printk("on issue queue ");
2476//#endif
2477		res = res_success;
2478	} else if (queue_remove_cmd(&host->queues.disconnected, SCpnt)) {
2479		/*
2480		 * The command was on the disconnected queue.  Simply
2481		 * acknowledge the abort condition, and when the target
2482		 * reconnects, we will give it an ABORT message.  The
2483		 * target should then disconnect, and we will clear
2484		 * the busylun bit.
2485		 */
2486//#if (DEBUG & DEBUG_ABORT)
2487		printk("on disconnected queue ");
2488//#endif
2489		res = res_success;
2490	} else if (host->SCpnt == SCpnt) {
2491		unsigned long flags;
2492
2493//#if (DEBUG & DEBUG_ABORT)
2494		printk("executing ");
2495//#endif
2496
2497		local_irq_save(flags);
2498		switch (host->scsi.phase) {
2499		/*
2500		 * If the interface is idle, and the command is 'disconnectable',
2501		 * then it is the same as on the disconnected queue.  We simply
2502		 * remove all traces of the command.  When the target reconnects,
2503		 * we will give it an ABORT message since the command could not
2504		 * be found.  When the target finally disconnects, we will clear
2505		 * the busylun bit.
2506		 */
2507		case PHASE_IDLE:
2508			if (host->scsi.disconnectable) {
2509				host->scsi.disconnectable = 0;
2510				host->SCpnt = NULL;
2511				res = res_success;
2512			}
2513			break;
2514
2515		/*
2516		 * If the command has connected and done nothing further,
2517		 * simply force a disconnect.  We also need to clear the
2518		 * busylun bit.
2519		 */
2520		case PHASE_CONNECTED:
2521			sbic_arm_write(host, SBIC_CMND, CMND_DISCONNECT);
2522			host->SCpnt = NULL;
2523			res = res_success_clear;
2524			break;
2525
2526		default:
2527			acornscsi_abortcmd(host);
2528			res = res_snooze;
2529		}
2530		local_irq_restore(flags);
2531	} else if (host->origSCpnt == SCpnt) {
2532		/*
2533		 * The command will be executed next, but a command
2534		 * is currently using the interface.  This is similar to
2535		 * being on the issue queue, except the busylun bit has
2536		 * been set.
2537		 */
2538		host->origSCpnt = NULL;
2539//#if (DEBUG & DEBUG_ABORT)
2540		printk("waiting for execution ");
2541//#endif
2542		res = res_success_clear;
2543	} else
2544		printk("unknown ");
2545
2546	return res;
2547}
2548
2549/*
2550 * Prototype: int acornscsi_abort(struct scsi_cmnd *SCpnt)
2551 * Purpose  : abort a command on this host
2552 * Params   : SCpnt - command to abort
2553 * Returns  : one of SCSI_ABORT_ macros
2554 */
2555int acornscsi_abort(struct scsi_cmnd *SCpnt)
2556{
2557	AS_Host *host = (AS_Host *) SCpnt->device->host->hostdata;
2558	int result;
2559
2560	host->stats.aborts += 1;
2561
2562#if (DEBUG & DEBUG_ABORT)
2563	{
2564		int asr, ssr;
2565		asr = sbic_arm_read(host, SBIC_ASR);
2566		ssr = sbic_arm_read(host, SBIC_SSR);
2567
2568		printk(KERN_WARNING "acornscsi_abort: ");
2569		print_sbic_status(asr, ssr, host->scsi.phase);
2570		acornscsi_dumplog(host, SCpnt->device->id);
2571	}
2572#endif
2573
2574	printk("scsi%d: ", host->host->host_no);
2575
2576	switch (acornscsi_do_abort(host, SCpnt)) {
2577	/*
2578	 * We managed to find the command and cleared it out.
2579	 * We do not expect the command to be executing on the
2580	 * target, but we have set the busylun bit.
2581	 */
2582	case res_success_clear:
2583//#if (DEBUG & DEBUG_ABORT)
2584		printk("clear ");
2585//#endif
2586		clear_bit(SCpnt->device->id * 8 +
2587			  (u8)(SCpnt->device->lun & 0x7), host->busyluns);
2588		fallthrough;
2589
2590	/*
2591	 * We found the command, and cleared it out.  Either
2592	 * the command is still known to be executing on the
2593	 * target, or the busylun bit is not set.
2594	 */
2595	case res_success:
2596//#if (DEBUG & DEBUG_ABORT)
2597		printk("success\n");
2598//#endif
2599		result = SUCCESS;
2600		break;
2601
2602	/*
2603	 * We did find the command, but unfortunately we couldn't
2604	 * unhook it from ourselves.  Wait some more, and if it
2605	 * still doesn't complete, reset the interface.
2606	 */
2607	case res_snooze:
2608//#if (DEBUG & DEBUG_ABORT)
2609		printk("snooze\n");
2610//#endif
2611		result = FAILED;
2612		break;
2613
2614	/*
2615	 * The command could not be found (either because it completed,
2616	 * or it got dropped.
2617	 */
2618	default:
2619	case res_not_running:
2620		acornscsi_dumplog(host, SCpnt->device->id);
2621		result = FAILED;
2622//#if (DEBUG & DEBUG_ABORT)
2623		printk("not running\n");
2624//#endif
2625		break;
2626	}
2627
2628	return result;
2629}
2630
2631/*
2632 * Prototype: int acornscsi_reset(struct scsi_cmnd *SCpnt)
2633 * Purpose  : reset a command on this host/reset this host
2634 * Params   : SCpnt  - command causing reset
2635 * Returns  : one of SCSI_RESET_ macros
2636 */
2637int acornscsi_host_reset(struct scsi_cmnd *SCpnt)
2638{
2639	AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2640	struct scsi_cmnd *SCptr;
2641
2642    host->stats.resets += 1;
2643
2644#if (DEBUG & DEBUG_RESET)
2645    {
2646	int asr, ssr, devidx;
2647
2648	asr = sbic_arm_read(host, SBIC_ASR);
2649	ssr = sbic_arm_read(host, SBIC_SSR);
2650
2651	printk(KERN_WARNING "acornscsi_reset: ");
2652	print_sbic_status(asr, ssr, host->scsi.phase);
2653	for (devidx = 0; devidx < 9; devidx++)
2654	    acornscsi_dumplog(host, devidx);
2655    }
2656#endif
2657
2658    acornscsi_dma_stop(host);
2659
2660    /*
2661     * do hard reset.  This resets all devices on this host, and so we
2662     * must set the reset status on all commands.
2663     */
2664    acornscsi_resetcard(host);
2665
2666    while ((SCptr = queue_remove(&host->queues.disconnected)) != NULL)
2667	;
2668
2669    return SUCCESS;
2670}
2671
2672/*==============================================================================================
2673 * initialisation & miscellaneous support
2674 */
2675
2676/*
2677 * Function: char *acornscsi_info(struct Scsi_Host *host)
2678 * Purpose : return a string describing this interface
2679 * Params  : host - host to give information on
2680 * Returns : a constant string
2681 */
2682const
2683char *acornscsi_info(struct Scsi_Host *host)
2684{
2685    static char string[100], *p;
2686
2687    p = string;
2688
2689    p += sprintf(string, "%s at port %08lX irq %d v%d.%d.%d"
2690#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2691    " SYNC"
2692#endif
2693#if (DEBUG & DEBUG_NO_WRITE)
2694    " NOWRITE (" __stringify(NO_WRITE) ")"
2695#endif
2696		, host->hostt->name, host->io_port, host->irq,
2697		VER_MAJOR, VER_MINOR, VER_PATCH);
2698    return string;
2699}
2700
2701static int acornscsi_show_info(struct seq_file *m, struct Scsi_Host *instance)
2702{
2703    int devidx;
2704    struct scsi_device *scd;
2705    AS_Host *host;
2706
2707    host  = (AS_Host *)instance->hostdata;
2708
2709    seq_printf(m, "AcornSCSI driver v%d.%d.%d"
2710#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2711    " SYNC"
2712#endif
2713#if (DEBUG & DEBUG_NO_WRITE)
2714    " NOWRITE (" __stringify(NO_WRITE) ")"
2715#endif
2716		"\n\n", VER_MAJOR, VER_MINOR, VER_PATCH);
2717
2718    seq_printf(m,	"SBIC: WD33C93A  Address: %p    IRQ : %d\n",
2719			host->base + SBIC_REGIDX, host->scsi.irq);
2720#ifdef USE_DMAC
2721    seq_printf(m,	"DMAC: uPC71071  Address: %p  IRQ : %d\n\n",
2722			host->base + DMAC_OFFSET, host->scsi.irq);
2723#endif
2724
2725    seq_printf(m,	"Statistics:\n"
2726			"Queued commands: %-10u    Issued commands: %-10u\n"
2727			"Done commands  : %-10u    Reads          : %-10u\n"
2728			"Writes         : %-10u    Others         : %-10u\n"
2729			"Disconnects    : %-10u    Aborts         : %-10u\n"
2730			"Resets         : %-10u\n\nLast phases:",
2731			host->stats.queues,		host->stats.removes,
2732			host->stats.fins,		host->stats.reads,
2733			host->stats.writes,		host->stats.miscs,
2734			host->stats.disconnects,	host->stats.aborts,
2735			host->stats.resets);
2736
2737    for (devidx = 0; devidx < 9; devidx ++) {
2738	unsigned int statptr, prev;
2739
2740	seq_printf(m, "\n%c:", devidx == 8 ? 'H' : ('0' + devidx));
2741	statptr = host->status_ptr[devidx] - 10;
2742
2743	if ((signed int)statptr < 0)
2744	    statptr += STATUS_BUFFER_SIZE;
2745
2746	prev = host->status[devidx][statptr].when;
2747
2748	for (; statptr != host->status_ptr[devidx]; statptr = (statptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
2749	    if (host->status[devidx][statptr].when) {
2750		seq_printf(m, "%c%02X:%02X+%2ld",
2751			host->status[devidx][statptr].irq ? '-' : ' ',
2752			host->status[devidx][statptr].ph,
2753			host->status[devidx][statptr].ssr,
2754			(host->status[devidx][statptr].when - prev) < 100 ?
2755				(host->status[devidx][statptr].when - prev) : 99);
2756		prev = host->status[devidx][statptr].when;
2757	    }
2758	}
2759    }
2760
2761    seq_printf(m, "\nAttached devices:\n");
2762
2763    shost_for_each_device(scd, instance) {
2764	seq_printf(m, "Device/Lun TaggedQ      Sync\n");
2765	seq_printf(m, "     %d/%llu   ", scd->id, scd->lun);
2766	if (scd->tagged_supported)
2767		seq_printf(m, "%3sabled ",
2768			     scd->simple_tags ? "en" : "dis");
2769	else
2770		seq_printf(m, "unsupported  ");
2771
2772	if (host->device[scd->id].sync_xfer & 15)
2773		seq_printf(m, "offset %d, %d ns\n",
2774			     host->device[scd->id].sync_xfer & 15,
2775			     acornscsi_getperiod(host->device[scd->id].sync_xfer));
2776	else
2777		seq_printf(m, "async\n");
2778
2779    }
2780    return 0;
2781}
2782
2783static const struct scsi_host_template acornscsi_template = {
2784	.module			= THIS_MODULE,
2785	.show_info		= acornscsi_show_info,
2786	.name			= "AcornSCSI",
2787	.info			= acornscsi_info,
2788	.queuecommand		= acornscsi_queuecmd,
2789	.eh_abort_handler	= acornscsi_abort,
2790	.eh_host_reset_handler	= acornscsi_host_reset,
2791	.can_queue		= 16,
2792	.this_id		= 7,
2793	.sg_tablesize		= SG_ALL,
2794	.cmd_per_lun		= 2,
2795	.dma_boundary		= PAGE_SIZE - 1,
2796	.proc_name		= "acornscsi",
2797	.cmd_size		= sizeof(struct arm_cmd_priv),
2798};
2799
2800static int acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
2801{
2802	struct Scsi_Host *host;
2803	AS_Host *ashost;
2804	int ret;
2805
2806	ret = ecard_request_resources(ec);
2807	if (ret)
2808		goto out;
2809
2810	host = scsi_host_alloc(&acornscsi_template, sizeof(AS_Host));
2811	if (!host) {
2812		ret = -ENOMEM;
2813		goto out_release;
2814	}
2815
2816	ashost = (AS_Host *)host->hostdata;
2817
2818	ashost->base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
2819	ashost->fast = ecardm_iomap(ec, ECARD_RES_IOCFAST, 0, 0);
2820	if (!ashost->base || !ashost->fast) {
2821		ret = -ENOMEM;
2822		goto out_put;
2823	}
2824
2825	host->irq = ec->irq;
2826	ashost->host = host;
2827	ashost->scsi.irq = host->irq;
2828
2829	ec->irqaddr	= ashost->fast + INT_REG;
2830	ec->irqmask	= 0x0a;
2831
2832	ret = request_irq(host->irq, acornscsi_intr, 0, "acornscsi", ashost);
2833	if (ret) {
2834		printk(KERN_CRIT "scsi%d: IRQ%d not free: %d\n",
2835			host->host_no, ashost->scsi.irq, ret);
2836		goto out_put;
2837	}
2838
2839	memset(&ashost->stats, 0, sizeof (ashost->stats));
2840	queue_initialise(&ashost->queues.issue);
2841	queue_initialise(&ashost->queues.disconnected);
2842	msgqueue_initialise(&ashost->scsi.msgs);
2843
2844	acornscsi_resetcard(ashost);
2845
2846	ret = scsi_add_host(host, &ec->dev);
2847	if (ret)
2848		goto out_irq;
2849
2850	scsi_scan_host(host);
2851	goto out;
2852
2853 out_irq:
2854	free_irq(host->irq, ashost);
2855	msgqueue_free(&ashost->scsi.msgs);
2856	queue_free(&ashost->queues.disconnected);
2857	queue_free(&ashost->queues.issue);
2858 out_put:
2859	ecardm_iounmap(ec, ashost->fast);
2860	ecardm_iounmap(ec, ashost->base);
2861	scsi_host_put(host);
2862 out_release:
2863	ecard_release_resources(ec);
2864 out:
2865	return ret;
2866}
2867
2868static void acornscsi_remove(struct expansion_card *ec)
2869{
2870	struct Scsi_Host *host = ecard_get_drvdata(ec);
2871	AS_Host *ashost = (AS_Host *)host->hostdata;
2872
2873	ecard_set_drvdata(ec, NULL);
2874	scsi_remove_host(host);
2875
2876	/*
2877	 * Put card into RESET state
2878	 */
2879	writeb(0x80, ashost->fast + PAGE_REG);
2880
2881	free_irq(host->irq, ashost);
2882
2883	msgqueue_free(&ashost->scsi.msgs);
2884	queue_free(&ashost->queues.disconnected);
2885	queue_free(&ashost->queues.issue);
2886	ecardm_iounmap(ec, ashost->fast);
2887	ecardm_iounmap(ec, ashost->base);
2888	scsi_host_put(host);
2889	ecard_release_resources(ec);
2890}
2891
2892static const struct ecard_id acornscsi_cids[] = {
2893	{ MANU_ACORN, PROD_ACORN_SCSI },
2894	{ 0xffff, 0xffff },
2895};
2896
2897static struct ecard_driver acornscsi_driver = {
2898	.probe		= acornscsi_probe,
2899	.remove		= acornscsi_remove,
2900	.id_table	= acornscsi_cids,
2901	.drv = {
2902		.name		= "acornscsi",
2903	},
2904};
2905
2906static int __init acornscsi_init(void)
2907{
2908	return ecard_register_driver(&acornscsi_driver);
2909}
2910
2911static void __exit acornscsi_exit(void)
2912{
2913	ecard_remove_driver(&acornscsi_driver);
2914}
2915
2916module_init(acornscsi_init);
2917module_exit(acornscsi_exit);
2918
2919MODULE_AUTHOR("Russell King");
2920MODULE_DESCRIPTION("AcornSCSI driver");
2921MODULE_LICENSE("GPL");
2922