xref: /linux/drivers/scsi/arm/acornscsi.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  *  linux/drivers/acorn/scsi/acornscsi.c
3  *
4  *  Acorn SCSI 3 driver
5  *  By R.M.King.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * Abandoned using the Select and Transfer command since there were
12  * some nasty races between our software and the target devices that
13  * were not easy to solve, and the device errata had a lot of entries
14  * for this command, some of them quite nasty...
15  *
16  * Changelog:
17  *  26-Sep-1997	RMK	Re-jigged to use the queue module.
18  *			Re-coded state machine to be based on driver
19  *			state not scsi state.  Should be easier to debug.
20  *			Added acornscsi_release to clean up properly.
21  *			Updated proc/scsi reporting.
22  *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
23  *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
24  *			reconnect race condition causing a warning message.
25  *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
26  *  15-Oct-1997	RMK	Improved handling of commands.
27  *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
28  *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
29  *			transitions added to allow dodgy devices to work.
30  */
31 #define DEBUG_NO_WRITE	1
32 #define DEBUG_QUEUES	2
33 #define DEBUG_DMA	4
34 #define DEBUG_ABORT	8
35 #define DEBUG_DISCON	16
36 #define DEBUG_CONNECT	32
37 #define DEBUG_PHASES	64
38 #define DEBUG_WRITE	128
39 #define DEBUG_LINK	256
40 #define DEBUG_MESSAGES	512
41 #define DEBUG_RESET	1024
42 #define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
43 			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
44 			 DEBUG_DMA|DEBUG_QUEUES)
45 
46 /* DRIVER CONFIGURATION
47  *
48  * SCSI-II Tagged queue support.
49  *
50  * I don't have any SCSI devices that support it, so it is totally untested
51  * (except to make sure that it doesn't interfere with any non-tagging
52  * devices).  It is not fully implemented either - what happens when a
53  * tagging device reconnects???
54  *
55  * You can tell if you have a device that supports tagged queueing my
56  * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
57  * as '2 TAG'.
58  *
59  * Also note that CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE is normally set in the config
60  * scripts, but disabled here.  Once debugged, remove the #undef, otherwise to debug,
61  * comment out the undef.
62  */
63 #undef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
64 /*
65  * SCSI-II Synchronous transfer support.
66  *
67  * Tried and tested...
68  *
69  * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
70  * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
71  * DEFAULT_PERIOD - default REQ period.
72  */
73 #define SDTR_SIZE	12
74 #define SDTR_PERIOD	125
75 #define DEFAULT_PERIOD	500
76 
77 /*
78  * Debugging information
79  *
80  * DEBUG	  - bit mask from list above
81  * DEBUG_TARGET   - is defined to the target number if you want to debug
82  *		    a specific target. [only recon/write/dma].
83  */
84 #define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
85 /* only allow writing to SCSI device 0 */
86 #define NO_WRITE 0xFE
87 /*#define DEBUG_TARGET 2*/
88 /*
89  * Select timeout time (in 10ms units)
90  *
91  * This is the timeout used between the start of selection and the WD33C93
92  * chip deciding that the device isn't responding.
93  */
94 #define TIMEOUT_TIME 10
95 /*
96  * Define this if you want to have verbose explanation of SCSI
97  * status/messages.
98  */
99 #undef CONFIG_ACORNSCSI_CONSTANTS
100 /*
101  * Define this if you want to use the on board DMAC [don't remove this option]
102  * If not set, then use PIO mode (not currently supported).
103  */
104 #define USE_DMAC
105 
106 /*
107  * ====================================================================================
108  */
109 
110 #ifdef DEBUG_TARGET
111 #define DBG(cmd,xxx...) \
112   if (cmd->device->id == DEBUG_TARGET) { \
113     xxx; \
114   }
115 #else
116 #define DBG(cmd,xxx...) xxx
117 #endif
118 
119 #include <linux/module.h>
120 #include <linux/kernel.h>
121 #include <linux/string.h>
122 #include <linux/signal.h>
123 #include <linux/errno.h>
124 #include <linux/proc_fs.h>
125 #include <linux/ioport.h>
126 #include <linux/blkdev.h>
127 #include <linux/delay.h>
128 #include <linux/interrupt.h>
129 #include <linux/init.h>
130 #include <linux/bitops.h>
131 #include <linux/stringify.h>
132 #include <linux/io.h>
133 
134 #include <asm/ecard.h>
135 
136 #include "../scsi.h"
137 #include <scsi/scsi_dbg.h>
138 #include <scsi/scsi_host.h>
139 #include <scsi/scsi_transport_spi.h>
140 #include "acornscsi.h"
141 #include "msgqueue.h"
142 #include "scsi.h"
143 
144 #include <scsi/scsicam.h>
145 
146 #define VER_MAJOR 2
147 #define VER_MINOR 0
148 #define VER_PATCH 6
149 
150 #ifndef ABORT_TAG
151 #define ABORT_TAG 0xd
152 #else
153 #error "Yippee!  ABORT TAG is now defined!  Remove this error!"
154 #endif
155 
156 #ifdef USE_DMAC
157 /*
158  * DMAC setup parameters
159  */
160 #define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
161 #define INIT_DEVCON1	(DEVCON1_BHLD)
162 #define DMAC_READ	(MODECON_READ)
163 #define DMAC_WRITE	(MODECON_WRITE)
164 #define INIT_SBICDMA	(CTRL_DMABURST)
165 
166 #define scsi_xferred	have_data_in
167 
168 /*
169  * Size of on-board DMA buffer
170  */
171 #define DMAC_BUFFER_SIZE	65536
172 #endif
173 
174 #define STATUS_BUFFER_TO_PRINT	24
175 
176 unsigned int sdtr_period = SDTR_PERIOD;
177 unsigned int sdtr_size   = SDTR_SIZE;
178 
179 static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
180 			   unsigned int result);
181 static int acornscsi_reconnect_finish(AS_Host *host);
182 static void acornscsi_dma_cleanup(AS_Host *host);
183 static void acornscsi_abortcmd(AS_Host *host, unsigned char tag);
184 
185 /* ====================================================================================
186  * Miscellaneous
187  */
188 
189 /* Offsets from MEMC base */
190 #define SBIC_REGIDX	0x2000
191 #define SBIC_REGVAL	0x2004
192 #define DMAC_OFFSET	0x3000
193 
194 /* Offsets from FAST IOC base */
195 #define INT_REG		0x2000
196 #define PAGE_REG	0x3000
197 
198 static inline void sbic_arm_write(AS_Host *host, unsigned int reg, unsigned int value)
199 {
200     writeb(reg, host->base + SBIC_REGIDX);
201     writeb(value, host->base + SBIC_REGVAL);
202 }
203 
204 static inline int sbic_arm_read(AS_Host *host, unsigned int reg)
205 {
206     if(reg == SBIC_ASR)
207 	   return readl(host->base + SBIC_REGIDX) & 255;
208     writeb(reg, host->base + SBIC_REGIDX);
209     return readl(host->base + SBIC_REGVAL) & 255;
210 }
211 
212 #define sbic_arm_writenext(host, val)	writeb((val), (host)->base + SBIC_REGVAL)
213 #define sbic_arm_readnext(host) 	readb((host)->base + SBIC_REGVAL)
214 
215 #ifdef USE_DMAC
216 #define dmac_read(host,reg) \
217 	readb((host)->base + DMAC_OFFSET + ((reg) << 2))
218 
219 #define dmac_write(host,reg,value) \
220 	({ writeb((value), (host)->base + DMAC_OFFSET + ((reg) << 2)); })
221 
222 #define dmac_clearintr(host) 	writeb(0, (host)->fast + INT_REG)
223 
224 static inline unsigned int dmac_address(AS_Host *host)
225 {
226     return dmac_read(host, DMAC_TXADRHI) << 16 |
227 	   dmac_read(host, DMAC_TXADRMD) << 8 |
228 	   dmac_read(host, DMAC_TXADRLO);
229 }
230 
231 static
232 void acornscsi_dumpdma(AS_Host *host, char *where)
233 {
234 	unsigned int mode, addr, len;
235 
236 	mode = dmac_read(host, DMAC_MODECON);
237 	addr = dmac_address(host);
238 	len  = dmac_read(host, DMAC_TXCNTHI) << 8 |
239 	       dmac_read(host, DMAC_TXCNTLO);
240 
241 	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
242 		host->host->host_no, where,
243 		mode, addr, (len + 1) & 0xffff,
244 		dmac_read(host, DMAC_MASKREG));
245 
246 	printk("DMA @%06x, ", host->dma.start_addr);
247 	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
248 		host->scsi.SCp.this_residual);
249 	printk("DT @+%04x ST @+%04x", host->dma.transferred,
250 		host->scsi.SCp.scsi_xferred);
251 	printk("\n");
252 }
253 #endif
254 
255 static
256 unsigned long acornscsi_sbic_xfcount(AS_Host *host)
257 {
258     unsigned long length;
259 
260     length = sbic_arm_read(host, SBIC_TRANSCNTH) << 16;
261     length |= sbic_arm_readnext(host) << 8;
262     length |= sbic_arm_readnext(host);
263 
264     return length;
265 }
266 
267 static int
268 acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
269 {
270 	int asr;
271 
272 	do {
273 		asr = sbic_arm_read(host, SBIC_ASR);
274 
275 		if ((asr & stat_mask) == stat)
276 			return 0;
277 
278 		udelay(1);
279 	} while (--timeout);
280 
281 	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);
282 
283 	return -1;
284 }
285 
286 static
287 int acornscsi_sbic_issuecmd(AS_Host *host, int command)
288 {
289     if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
290 	return -1;
291 
292     sbic_arm_write(host, SBIC_CMND, command);
293 
294     return 0;
295 }
296 
297 static void
298 acornscsi_csdelay(unsigned int cs)
299 {
300     unsigned long target_jiffies, flags;
301 
302     target_jiffies = jiffies + 1 + cs * HZ / 100;
303 
304     local_save_flags(flags);
305     local_irq_enable();
306 
307     while (time_before(jiffies, target_jiffies)) barrier();
308 
309     local_irq_restore(flags);
310 }
311 
312 static
313 void acornscsi_resetcard(AS_Host *host)
314 {
315     unsigned int i, timeout;
316 
317     /* assert reset line */
318     host->card.page_reg = 0x80;
319     writeb(host->card.page_reg, host->fast + PAGE_REG);
320 
321     /* wait 3 cs.  SCSI standard says 25ms. */
322     acornscsi_csdelay(3);
323 
324     host->card.page_reg = 0;
325     writeb(host->card.page_reg, host->fast + PAGE_REG);
326 
327     /*
328      * Should get a reset from the card
329      */
330     timeout = 1000;
331     do {
332 	if (readb(host->fast + INT_REG) & 8)
333 	    break;
334 	udelay(1);
335     } while (--timeout);
336 
337     if (timeout == 0)
338 	printk("scsi%d: timeout while resetting card\n",
339 		host->host->host_no);
340 
341     sbic_arm_read(host, SBIC_ASR);
342     sbic_arm_read(host, SBIC_SSR);
343 
344     /* setup sbic - WD33C93A */
345     sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
346     sbic_arm_write(host, SBIC_CMND, CMND_RESET);
347 
348     /*
349      * Command should cause a reset interrupt
350      */
351     timeout = 1000;
352     do {
353 	if (readb(host->fast + INT_REG) & 8)
354 	    break;
355 	udelay(1);
356     } while (--timeout);
357 
358     if (timeout == 0)
359 	printk("scsi%d: timeout while resetting card\n",
360 		host->host->host_no);
361 
362     sbic_arm_read(host, SBIC_ASR);
363     if (sbic_arm_read(host, SBIC_SSR) != 0x01)
364 	printk(KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
365 		host->host->host_no);
366 
367     sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
368     sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
369     sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
370     sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
371 
372     host->card.page_reg = 0x40;
373     writeb(host->card.page_reg, host->fast + PAGE_REG);
374 
375     /* setup dmac - uPC71071 */
376     dmac_write(host, DMAC_INIT, 0);
377 #ifdef USE_DMAC
378     dmac_write(host, DMAC_INIT, INIT_8BIT);
379     dmac_write(host, DMAC_CHANNEL, CHANNEL_0);
380     dmac_write(host, DMAC_DEVCON0, INIT_DEVCON0);
381     dmac_write(host, DMAC_DEVCON1, INIT_DEVCON1);
382 #endif
383 
384     host->SCpnt = NULL;
385     host->scsi.phase = PHASE_IDLE;
386     host->scsi.disconnectable = 0;
387 
388     memset(host->busyluns, 0, sizeof(host->busyluns));
389 
390     for (i = 0; i < 8; i++) {
391 	host->device[i].sync_state = SYNC_NEGOCIATE;
392 	host->device[i].disconnect_ok = 1;
393     }
394 
395     /* wait 25 cs.  SCSI standard says 250ms. */
396     acornscsi_csdelay(25);
397 }
398 
399 /*=============================================================================================
400  * Utility routines (eg. debug)
401  */
402 #ifdef CONFIG_ACORNSCSI_CONSTANTS
403 static char *acornscsi_interrupttype[] = {
404   "rst",  "suc",  "p/a",  "3",
405   "term", "5",	  "6",	  "7",
406   "serv", "9",	  "a",	  "b",
407   "c",	  "d",	  "e",	  "f"
408 };
409 
410 static signed char acornscsi_map[] = {
411   0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
412  -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
413  12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
414  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
415  15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
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  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
419  21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
420  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
421  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
422  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
423  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
424  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
425  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
426  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
427 };
428 
429 static char *acornscsi_interruptcode[] = {
430     /* 0 */
431     "reset - normal mode",	/* 00 */
432     "reset - advanced mode",	/* 01 */
433 
434     /* 2 */
435     "sel",			/* 11 */
436     "sel+xfer", 		/* 16 */
437     "data-out", 		/* 18 */
438     "data-in",			/* 19 */
439     "cmd",			/* 1A */
440     "stat",			/* 1B */
441     "??-out",			/* 1C */
442     "??-in",			/* 1D */
443     "msg-out",			/* 1E */
444     "msg-in",			/* 1F */
445 
446     /* 12 */
447     "/ACK asserted",		/* 20 */
448     "save-data-ptr",		/* 21 */
449     "{re}sel",			/* 22 */
450 
451     /* 15 */
452     "inv cmd",			/* 40 */
453     "unexpected disconnect",	/* 41 */
454     "sel timeout",		/* 42 */
455     "P err",			/* 43 */
456     "P err+ATN",		/* 44 */
457     "bad status byte",		/* 47 */
458 
459     /* 21 */
460     "resel, no id",		/* 80 */
461     "resel",			/* 81 */
462     "discon",			/* 85 */
463 };
464 
465 static
466 void print_scsi_status(unsigned int ssr)
467 {
468     if (acornscsi_map[ssr] != -1)
469 	printk("%s:%s",
470 		acornscsi_interrupttype[(ssr >> 4)],
471 		acornscsi_interruptcode[acornscsi_map[ssr]]);
472     else
473 	printk("%X:%X", ssr >> 4, ssr & 0x0f);
474 }
475 #endif
476 
477 static
478 void print_sbic_status(int asr, int ssr, int cmdphase)
479 {
480 #ifdef CONFIG_ACORNSCSI_CONSTANTS
481     printk("sbic: %c%c%c%c%c%c ",
482 	    asr & ASR_INT ? 'I' : 'i',
483 	    asr & ASR_LCI ? 'L' : 'l',
484 	    asr & ASR_BSY ? 'B' : 'b',
485 	    asr & ASR_CIP ? 'C' : 'c',
486 	    asr & ASR_PE  ? 'P' : 'p',
487 	    asr & ASR_DBR ? 'D' : 'd');
488     printk("scsi: ");
489     print_scsi_status(ssr);
490     printk(" ph %02X\n", cmdphase);
491 #else
492     printk("sbic: %02X scsi: %X:%X ph: %02X\n",
493 	    asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
494 #endif
495 }
496 
497 static void
498 acornscsi_dumplogline(AS_Host *host, int target, int line)
499 {
500 	unsigned long prev;
501 	signed int ptr;
502 
503 	ptr = host->status_ptr[target] - STATUS_BUFFER_TO_PRINT;
504 	if (ptr < 0)
505 		ptr += STATUS_BUFFER_SIZE;
506 
507 	printk("%c: %3s:", target == 8 ? 'H' : '0' + target,
508 		line == 0 ? "ph" : line == 1 ? "ssr" : "int");
509 
510 	prev = host->status[target][ptr].when;
511 
512 	for (; ptr != host->status_ptr[target]; ptr = (ptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
513 		unsigned long time_diff;
514 
515 		if (!host->status[target][ptr].when)
516 			continue;
517 
518 		switch (line) {
519 		case 0:
520 			printk("%c%02X", host->status[target][ptr].irq ? '-' : ' ',
521 					 host->status[target][ptr].ph);
522 			break;
523 
524 		case 1:
525 			printk(" %02X", host->status[target][ptr].ssr);
526 			break;
527 
528 		case 2:
529 			time_diff = host->status[target][ptr].when - prev;
530 			prev = host->status[target][ptr].when;
531 			if (time_diff == 0)
532 				printk("==^");
533 			else if (time_diff >= 100)
534 				printk("   ");
535 			else
536 				printk(" %02ld", time_diff);
537 			break;
538 		}
539 	}
540 
541 	printk("\n");
542 }
543 
544 static
545 void acornscsi_dumplog(AS_Host *host, int target)
546 {
547     do {
548 	acornscsi_dumplogline(host, target, 0);
549 	acornscsi_dumplogline(host, target, 1);
550 	acornscsi_dumplogline(host, target, 2);
551 
552 	if (target == 8)
553 	    break;
554 
555 	target = 8;
556     } while (1);
557 }
558 
559 static
560 char acornscsi_target(AS_Host *host)
561 {
562 	if (host->SCpnt)
563 		return '0' + host->SCpnt->device->id;
564 	return 'H';
565 }
566 
567 /*
568  * Prototype: cmdtype_t acornscsi_cmdtype(int command)
569  * Purpose  : differentiate READ from WRITE from other commands
570  * Params   : command - command to interpret
571  * Returns  : CMD_READ	- command reads data,
572  *	      CMD_WRITE - command writes data,
573  *	      CMD_MISC	- everything else
574  */
575 static inline
576 cmdtype_t acornscsi_cmdtype(int command)
577 {
578     switch (command) {
579     case WRITE_6:  case WRITE_10:  case WRITE_12:
580 	return CMD_WRITE;
581     case READ_6:   case READ_10:   case READ_12:
582 	return CMD_READ;
583     default:
584 	return CMD_MISC;
585     }
586 }
587 
588 /*
589  * Prototype: int acornscsi_datadirection(int command)
590  * Purpose  : differentiate between commands that have a DATA IN phase
591  *	      and a DATA OUT phase
592  * Params   : command - command to interpret
593  * Returns  : DATADIR_OUT - data out phase expected
594  *	      DATADIR_IN  - data in phase expected
595  */
596 static
597 datadir_t acornscsi_datadirection(int command)
598 {
599     switch (command) {
600     case CHANGE_DEFINITION:	case COMPARE:		case COPY:
601     case COPY_VERIFY:		case LOG_SELECT:	case MODE_SELECT:
602     case MODE_SELECT_10:	case SEND_DIAGNOSTIC:	case WRITE_BUFFER:
603     case FORMAT_UNIT:		case REASSIGN_BLOCKS:	case RESERVE:
604     case SEARCH_EQUAL:		case SEARCH_HIGH:	case SEARCH_LOW:
605     case WRITE_6:		case WRITE_10:		case WRITE_VERIFY:
606     case UPDATE_BLOCK:		case WRITE_LONG:	case WRITE_SAME:
607     case SEARCH_HIGH_12:	case SEARCH_EQUAL_12:	case SEARCH_LOW_12:
608     case WRITE_12:		case WRITE_VERIFY_12:	case SET_WINDOW:
609     case MEDIUM_SCAN:		case SEND_VOLUME_TAG:	case 0xea:
610 	return DATADIR_OUT;
611     default:
612 	return DATADIR_IN;
613     }
614 }
615 
616 /*
617  * Purpose  : provide values for synchronous transfers with 33C93.
618  * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
619  *	Modified by Russell King for 8MHz WD33C93A
620  */
621 static struct sync_xfer_tbl {
622     unsigned int period_ns;
623     unsigned char reg_value;
624 } sync_xfer_table[] = {
625     {	1, 0x20 },    { 249, 0x20 },	{ 374, 0x30 },
626     { 499, 0x40 },    { 624, 0x50 },	{ 749, 0x60 },
627     { 874, 0x70 },    { 999, 0x00 },	{   0,	  0 }
628 };
629 
630 /*
631  * Prototype: int acornscsi_getperiod(unsigned char syncxfer)
632  * Purpose  : period for the synchronous transfer setting
633  * Params   : syncxfer SYNCXFER register value
634  * Returns  : period in ns.
635  */
636 static
637 int acornscsi_getperiod(unsigned char syncxfer)
638 {
639     int i;
640 
641     syncxfer &= 0xf0;
642     if (syncxfer == 0x10)
643 	syncxfer = 0;
644 
645     for (i = 1; sync_xfer_table[i].period_ns; i++)
646 	if (syncxfer == sync_xfer_table[i].reg_value)
647 	    return sync_xfer_table[i].period_ns;
648     return 0;
649 }
650 
651 /*
652  * Prototype: int round_period(unsigned int period)
653  * Purpose  : return index into above table for a required REQ period
654  * Params   : period - time (ns) for REQ
655  * Returns  : table index
656  * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
657  */
658 static inline
659 int round_period(unsigned int period)
660 {
661     int i;
662 
663     for (i = 1; sync_xfer_table[i].period_ns; i++) {
664 	if ((period <= sync_xfer_table[i].period_ns) &&
665 	    (period > sync_xfer_table[i - 1].period_ns))
666 	    return i;
667     }
668     return 7;
669 }
670 
671 /*
672  * Prototype: unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
673  * Purpose  : calculate value for 33c93s SYNC register
674  * Params   : period - time (ns) for REQ
675  *	      offset - offset in bytes between REQ/ACK
676  * Returns  : value for SYNC register
677  * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
678  */
679 static
680 unsigned char __maybe_unused calc_sync_xfer(unsigned int period,
681 					    unsigned int offset)
682 {
683     return sync_xfer_table[round_period(period)].reg_value |
684 		((offset < SDTR_SIZE) ? offset : SDTR_SIZE);
685 }
686 
687 /* ====================================================================================
688  * Command functions
689  */
690 /*
691  * Function: acornscsi_kick(AS_Host *host)
692  * Purpose : kick next command to interface
693  * Params  : host - host to send command to
694  * Returns : INTR_IDLE if idle, otherwise INTR_PROCESSING
695  * Notes   : interrupts are always disabled!
696  */
697 static
698 intr_ret_t acornscsi_kick(AS_Host *host)
699 {
700     int from_queue = 0;
701     struct scsi_cmnd *SCpnt;
702 
703     /* first check to see if a command is waiting to be executed */
704     SCpnt = host->origSCpnt;
705     host->origSCpnt = NULL;
706 
707     /* retrieve next command */
708     if (!SCpnt) {
709 	SCpnt = queue_remove_exclude(&host->queues.issue, host->busyluns);
710 	if (!SCpnt)
711 	    return INTR_IDLE;
712 
713 	from_queue = 1;
714     }
715 
716     if (host->scsi.disconnectable && host->SCpnt) {
717 	queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
718 	host->scsi.disconnectable = 0;
719 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
720 	DBG(host->SCpnt, printk("scsi%d.%c: moved command to disconnected queue\n",
721 		host->host->host_no, acornscsi_target(host)));
722 #endif
723 	host->SCpnt = NULL;
724     }
725 
726     /*
727      * If we have an interrupt pending, then we may have been reselected.
728      * In this case, we don't want to write to the registers
729      */
730     if (!(sbic_arm_read(host, SBIC_ASR) & (ASR_INT|ASR_BSY|ASR_CIP))) {
731 	sbic_arm_write(host, SBIC_DESTID, SCpnt->device->id);
732 	sbic_arm_write(host, SBIC_CMND, CMND_SELWITHATN);
733     }
734 
735     /*
736      * claim host busy - all of these must happen atomically wrt
737      * our interrupt routine.  Failure means command loss.
738      */
739     host->scsi.phase = PHASE_CONNECTING;
740     host->SCpnt = SCpnt;
741     host->scsi.SCp = SCpnt->SCp;
742     host->dma.xfer_setup = 0;
743     host->dma.xfer_required = 0;
744     host->dma.xfer_done = 0;
745 
746 #if (DEBUG & (DEBUG_ABORT|DEBUG_CONNECT))
747     DBG(SCpnt,printk("scsi%d.%c: starting cmd %02X\n",
748 	    host->host->host_no, '0' + SCpnt->device->id,
749 	    SCpnt->cmnd[0]));
750 #endif
751 
752     if (from_queue) {
753 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
754 	/*
755 	 * tagged queueing - allocate a new tag to this command
756 	 */
757 	if (SCpnt->device->simple_tags) {
758 	    SCpnt->device->current_tag += 1;
759 	    if (SCpnt->device->current_tag == 0)
760 		SCpnt->device->current_tag = 1;
761 	    SCpnt->tag = SCpnt->device->current_tag;
762 	} else
763 #endif
764 	    set_bit(SCpnt->device->id * 8 +
765 		    (u8)(SCpnt->device->lun & 0x07), host->busyluns);
766 
767 	host->stats.removes += 1;
768 
769 	switch (acornscsi_cmdtype(SCpnt->cmnd[0])) {
770 	case CMD_WRITE:
771 	    host->stats.writes += 1;
772 	    break;
773 	case CMD_READ:
774 	    host->stats.reads += 1;
775 	    break;
776 	case CMD_MISC:
777 	    host->stats.miscs += 1;
778 	    break;
779 	}
780     }
781 
782     return INTR_PROCESSING;
783 }
784 
785 /*
786  * Function: void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp, unsigned int result)
787  * Purpose : complete processing for command
788  * Params  : host   - interface that completed
789  *	     result - driver byte of result
790  */
791 static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
792 			   unsigned int result)
793 {
794 	struct scsi_cmnd *SCpnt = *SCpntp;
795 
796     /* clean up */
797     sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
798 
799     host->stats.fins += 1;
800 
801     if (SCpnt) {
802 	*SCpntp = NULL;
803 
804 	acornscsi_dma_cleanup(host);
805 
806 	SCpnt->result = result << 16 | host->scsi.SCp.Message << 8 | host->scsi.SCp.Status;
807 
808 	/*
809 	 * In theory, this should not happen.  In practice, it seems to.
810 	 * Only trigger an error if the device attempts to report all happy
811 	 * but with untransferred buffers...  If we don't do something, then
812 	 * data loss will occur.  Should we check SCpnt->underflow here?
813 	 * It doesn't appear to be set to something meaningful by the higher
814 	 * levels all the time.
815 	 */
816 	if (result == DID_OK) {
817 		int xfer_warn = 0;
818 
819 		if (SCpnt->underflow == 0) {
820 			if (host->scsi.SCp.ptr &&
821 			    acornscsi_cmdtype(SCpnt->cmnd[0]) != CMD_MISC)
822 				xfer_warn = 1;
823 		} else {
824 			if (host->scsi.SCp.scsi_xferred < SCpnt->underflow ||
825 			    host->scsi.SCp.scsi_xferred != host->dma.transferred)
826 				xfer_warn = 1;
827 		}
828 
829 		/* ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.6)
830 		 *  Targets which break data transfers into multiple
831 		 *  connections shall end each successful connection
832 		 *  (except possibly the last) with a SAVE DATA
833 		 *  POINTER - DISCONNECT message sequence.
834 		 *
835 		 * This makes it difficult to ensure that a transfer has
836 		 * completed.  If we reach the end of a transfer during
837 		 * the command, then we can only have finished the transfer.
838 		 * therefore, if we seem to have some data remaining, this
839 		 * is not a problem.
840 		 */
841 		if (host->dma.xfer_done)
842 			xfer_warn = 0;
843 
844 		if (xfer_warn) {
845 		    switch (status_byte(SCpnt->result)) {
846 		    case CHECK_CONDITION:
847 		    case COMMAND_TERMINATED:
848 		    case BUSY:
849 		    case QUEUE_FULL:
850 		    case RESERVATION_CONFLICT:
851 			break;
852 
853 		    default:
854 			scmd_printk(KERN_ERR, SCpnt,
855 				    "incomplete data transfer detected: "
856 				    "result=%08X", SCpnt->result);
857 			scsi_print_command(SCpnt);
858 			acornscsi_dumpdma(host, "done");
859 			acornscsi_dumplog(host, SCpnt->device->id);
860 			set_host_byte(SCpnt, DID_ERROR);
861 		    }
862 		}
863 	}
864 
865 	if (!SCpnt->scsi_done)
866 	    panic("scsi%d.H: null scsi_done function in acornscsi_done", host->host->host_no);
867 
868 	clear_bit(SCpnt->device->id * 8 +
869 		  (u8)(SCpnt->device->lun & 0x7), host->busyluns);
870 
871 	SCpnt->scsi_done(SCpnt);
872     } else
873 	printk("scsi%d: null command in acornscsi_done", host->host->host_no);
874 
875     host->scsi.phase = PHASE_IDLE;
876 }
877 
878 /* ====================================================================================
879  * DMA routines
880  */
881 /*
882  * Purpose  : update SCSI Data Pointer
883  * Notes    : this will only be one SG entry or less
884  */
885 static
886 void acornscsi_data_updateptr(AS_Host *host, struct scsi_pointer *SCp, unsigned int length)
887 {
888     SCp->ptr += length;
889     SCp->this_residual -= length;
890 
891     if (SCp->this_residual == 0 && next_SCp(SCp) == 0)
892 	host->dma.xfer_done = 1;
893 }
894 
895 /*
896  * Prototype: void acornscsi_data_read(AS_Host *host, char *ptr,
897  *				unsigned int start_addr, unsigned int length)
898  * Purpose  : read data from DMA RAM
899  * Params   : host - host to transfer from
900  *	      ptr  - DRAM address
901  *	      start_addr - host mem address
902  *	      length - number of bytes to transfer
903  * Notes    : this will only be one SG entry or less
904  */
905 static
906 void acornscsi_data_read(AS_Host *host, char *ptr,
907 				 unsigned int start_addr, unsigned int length)
908 {
909     extern void __acornscsi_in(void __iomem *, char *buf, int len);
910     unsigned int page, offset, len = length;
911 
912     page = (start_addr >> 12);
913     offset = start_addr & ((1 << 12) - 1);
914 
915     writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
916 
917     while (len > 0) {
918 	unsigned int this_len;
919 
920 	if (len + offset > (1 << 12))
921 	    this_len = (1 << 12) - offset;
922 	else
923 	    this_len = len;
924 
925 	__acornscsi_in(host->base + (offset << 1), ptr, this_len);
926 
927 	offset += this_len;
928 	ptr += this_len;
929 	len -= this_len;
930 
931 	if (offset == (1 << 12)) {
932 	    offset = 0;
933 	    page ++;
934 	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
935 	}
936     }
937     writeb(host->card.page_reg, host->fast + PAGE_REG);
938 }
939 
940 /*
941  * Prototype: void acornscsi_data_write(AS_Host *host, char *ptr,
942  *				unsigned int start_addr, unsigned int length)
943  * Purpose  : write data to DMA RAM
944  * Params   : host - host to transfer from
945  *	      ptr  - DRAM address
946  *	      start_addr - host mem address
947  *	      length - number of bytes to transfer
948  * Notes    : this will only be one SG entry or less
949  */
950 static
951 void acornscsi_data_write(AS_Host *host, char *ptr,
952 				 unsigned int start_addr, unsigned int length)
953 {
954     extern void __acornscsi_out(void __iomem *, char *buf, int len);
955     unsigned int page, offset, len = length;
956 
957     page = (start_addr >> 12);
958     offset = start_addr & ((1 << 12) - 1);
959 
960     writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
961 
962     while (len > 0) {
963 	unsigned int this_len;
964 
965 	if (len + offset > (1 << 12))
966 	    this_len = (1 << 12) - offset;
967 	else
968 	    this_len = len;
969 
970 	__acornscsi_out(host->base + (offset << 1), ptr, this_len);
971 
972 	offset += this_len;
973 	ptr += this_len;
974 	len -= this_len;
975 
976 	if (offset == (1 << 12)) {
977 	    offset = 0;
978 	    page ++;
979 	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
980 	}
981     }
982     writeb(host->card.page_reg, host->fast + PAGE_REG);
983 }
984 
985 /* =========================================================================================
986  * On-board DMA routines
987  */
988 #ifdef USE_DMAC
989 /*
990  * Prototype: void acornscsi_dmastop(AS_Host *host)
991  * Purpose  : stop all DMA
992  * Params   : host - host on which to stop DMA
993  * Notes    : This is called when leaving DATA IN/OUT phase,
994  *	      or when interface is RESET
995  */
996 static inline
997 void acornscsi_dma_stop(AS_Host *host)
998 {
999     dmac_write(host, DMAC_MASKREG, MASK_ON);
1000     dmac_clearintr(host);
1001 
1002 #if (DEBUG & DEBUG_DMA)
1003     DBG(host->SCpnt, acornscsi_dumpdma(host, "stop"));
1004 #endif
1005 }
1006 
1007 /*
1008  * Function: void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1009  * Purpose : setup DMA controller for data transfer
1010  * Params  : host - host to setup
1011  *	     direction - data transfer direction
1012  * Notes   : This is called when entering DATA I/O phase, not
1013  *	     while we're in a DATA I/O phase
1014  */
1015 static
1016 void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
1017 {
1018     unsigned int address, length, mode;
1019 
1020     host->dma.direction = direction;
1021 
1022     dmac_write(host, DMAC_MASKREG, MASK_ON);
1023 
1024     if (direction == DMA_OUT) {
1025 #if (DEBUG & DEBUG_NO_WRITE)
1026 	if (NO_WRITE & (1 << host->SCpnt->device->id)) {
1027 	    printk(KERN_CRIT "scsi%d.%c: I can't handle DMA_OUT!\n",
1028 		    host->host->host_no, acornscsi_target(host));
1029 	    return;
1030 	}
1031 #endif
1032 	mode = DMAC_WRITE;
1033     } else
1034 	mode = DMAC_READ;
1035 
1036     /*
1037      * Allocate some buffer space, limited to half the buffer size
1038      */
1039     length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1040     if (length) {
1041 	host->dma.start_addr = address = host->dma.free_addr;
1042 	host->dma.free_addr = (host->dma.free_addr + length) &
1043 				(DMAC_BUFFER_SIZE - 1);
1044 
1045 	/*
1046 	 * Transfer data to DMA memory
1047 	 */
1048 	if (direction == DMA_OUT)
1049 	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1050 				length);
1051 
1052 	length -= 1;
1053 	dmac_write(host, DMAC_TXCNTLO, length);
1054 	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1055 	dmac_write(host, DMAC_TXADRLO, address);
1056 	dmac_write(host, DMAC_TXADRMD, address >> 8);
1057 	dmac_write(host, DMAC_TXADRHI, 0);
1058 	dmac_write(host, DMAC_MODECON, mode);
1059 	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1060 
1061 #if (DEBUG & DEBUG_DMA)
1062 	DBG(host->SCpnt, acornscsi_dumpdma(host, "strt"));
1063 #endif
1064 	host->dma.xfer_setup = 1;
1065     }
1066 }
1067 
1068 /*
1069  * Function: void acornscsi_dma_cleanup(AS_Host *host)
1070  * Purpose : ensure that all DMA transfers are up-to-date & host->scsi.SCp is correct
1071  * Params  : host - host to finish
1072  * Notes   : This is called when a command is:
1073  *		terminating, RESTORE_POINTERS, SAVE_POINTERS, DISCONECT
1074  *	   : This must not return until all transfers are completed.
1075  */
1076 static
1077 void acornscsi_dma_cleanup(AS_Host *host)
1078 {
1079     dmac_write(host, DMAC_MASKREG, MASK_ON);
1080     dmac_clearintr(host);
1081 
1082     /*
1083      * Check for a pending transfer
1084      */
1085     if (host->dma.xfer_required) {
1086 	host->dma.xfer_required = 0;
1087 	if (host->dma.direction == DMA_IN)
1088 	    acornscsi_data_read(host, host->dma.xfer_ptr,
1089 				 host->dma.xfer_start, host->dma.xfer_length);
1090     }
1091 
1092     /*
1093      * Has a transfer been setup?
1094      */
1095     if (host->dma.xfer_setup) {
1096 	unsigned int transferred;
1097 
1098 	host->dma.xfer_setup = 0;
1099 
1100 #if (DEBUG & DEBUG_DMA)
1101 	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupi"));
1102 #endif
1103 
1104 	/*
1105 	 * Calculate number of bytes transferred from DMA.
1106 	 */
1107 	transferred = dmac_address(host) - host->dma.start_addr;
1108 	host->dma.transferred += transferred;
1109 
1110 	if (host->dma.direction == DMA_IN)
1111 	    acornscsi_data_read(host, host->scsi.SCp.ptr,
1112 				 host->dma.start_addr, transferred);
1113 
1114 	/*
1115 	 * Update SCSI pointers
1116 	 */
1117 	acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1118 #if (DEBUG & DEBUG_DMA)
1119 	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupo"));
1120 #endif
1121     }
1122 }
1123 
1124 /*
1125  * Function: void acornscsi_dmacintr(AS_Host *host)
1126  * Purpose : handle interrupts from DMAC device
1127  * Params  : host - host to process
1128  * Notes   : If reading, we schedule the read to main memory &
1129  *	     allow the transfer to continue.
1130  *	   : If writing, we fill the onboard DMA memory from main
1131  *	     memory.
1132  *	   : Called whenever DMAC finished it's current transfer.
1133  */
1134 static
1135 void acornscsi_dma_intr(AS_Host *host)
1136 {
1137     unsigned int address, length, transferred;
1138 
1139 #if (DEBUG & DEBUG_DMA)
1140     DBG(host->SCpnt, acornscsi_dumpdma(host, "inti"));
1141 #endif
1142 
1143     dmac_write(host, DMAC_MASKREG, MASK_ON);
1144     dmac_clearintr(host);
1145 
1146     /*
1147      * Calculate amount transferred via DMA
1148      */
1149     transferred = dmac_address(host) - host->dma.start_addr;
1150     host->dma.transferred += transferred;
1151 
1152     /*
1153      * Schedule DMA transfer off board
1154      */
1155     if (host->dma.direction == DMA_IN) {
1156 	host->dma.xfer_start = host->dma.start_addr;
1157 	host->dma.xfer_length = transferred;
1158 	host->dma.xfer_ptr = host->scsi.SCp.ptr;
1159 	host->dma.xfer_required = 1;
1160     }
1161 
1162     acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
1163 
1164     /*
1165      * Allocate some buffer space, limited to half the on-board RAM size
1166      */
1167     length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
1168     if (length) {
1169 	host->dma.start_addr = address = host->dma.free_addr;
1170 	host->dma.free_addr = (host->dma.free_addr + length) &
1171 				(DMAC_BUFFER_SIZE - 1);
1172 
1173 	/*
1174 	 * Transfer data to DMA memory
1175 	 */
1176 	if (host->dma.direction == DMA_OUT)
1177 	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
1178 				length);
1179 
1180 	length -= 1;
1181 	dmac_write(host, DMAC_TXCNTLO, length);
1182 	dmac_write(host, DMAC_TXCNTHI, length >> 8);
1183 	dmac_write(host, DMAC_TXADRLO, address);
1184 	dmac_write(host, DMAC_TXADRMD, address >> 8);
1185 	dmac_write(host, DMAC_TXADRHI, 0);
1186 	dmac_write(host, DMAC_MASKREG, MASK_OFF);
1187 
1188 #if (DEBUG & DEBUG_DMA)
1189 	DBG(host->SCpnt, acornscsi_dumpdma(host, "into"));
1190 #endif
1191     } else {
1192 	host->dma.xfer_setup = 0;
1193 #if 0
1194 	/*
1195 	 * If the interface still wants more, then this is an error.
1196 	 * We give it another byte, but we also attempt to raise an
1197 	 * attention condition.  We continue giving one byte until
1198 	 * the device recognises the attention.
1199 	 */
1200 	if (dmac_read(host, DMAC_STATUS) & STATUS_RQ0) {
1201 	    acornscsi_abortcmd(host, host->SCpnt->tag);
1202 
1203 	    dmac_write(host, DMAC_TXCNTLO, 0);
1204 	    dmac_write(host, DMAC_TXCNTHI, 0);
1205 	    dmac_write(host, DMAC_TXADRLO, 0);
1206 	    dmac_write(host, DMAC_TXADRMD, 0);
1207 	    dmac_write(host, DMAC_TXADRHI, 0);
1208 	    dmac_write(host, DMAC_MASKREG, MASK_OFF);
1209 	}
1210 #endif
1211     }
1212 }
1213 
1214 /*
1215  * Function: void acornscsi_dma_xfer(AS_Host *host)
1216  * Purpose : transfer data between AcornSCSI and memory
1217  * Params  : host - host to process
1218  */
1219 static
1220 void acornscsi_dma_xfer(AS_Host *host)
1221 {
1222     host->dma.xfer_required = 0;
1223 
1224     if (host->dma.direction == DMA_IN)
1225 	acornscsi_data_read(host, host->dma.xfer_ptr,
1226 				host->dma.xfer_start, host->dma.xfer_length);
1227 }
1228 
1229 /*
1230  * Function: void acornscsi_dma_adjust(AS_Host *host)
1231  * Purpose : adjust DMA pointers & count for bytes transferred to
1232  *	     SBIC but not SCSI bus.
1233  * Params  : host - host to adjust DMA count for
1234  */
1235 static
1236 void acornscsi_dma_adjust(AS_Host *host)
1237 {
1238     if (host->dma.xfer_setup) {
1239 	signed long transferred;
1240 #if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1241 	DBG(host->SCpnt, acornscsi_dumpdma(host, "adji"));
1242 #endif
1243 	/*
1244 	 * Calculate correct DMA address - DMA is ahead of SCSI bus while
1245 	 * writing.
1246 	 *  host->scsi.SCp.scsi_xferred is the number of bytes
1247 	 *  actually transferred to/from the SCSI bus.
1248 	 *  host->dma.transferred is the number of bytes transferred
1249 	 *  over DMA since host->dma.start_addr was last set.
1250 	 *
1251 	 * real_dma_addr = host->dma.start_addr + host->scsi.SCp.scsi_xferred
1252 	 *		   - host->dma.transferred
1253 	 */
1254 	transferred = host->scsi.SCp.scsi_xferred - host->dma.transferred;
1255 	if (transferred < 0)
1256 	    printk("scsi%d.%c: Ack! DMA write correction %ld < 0!\n",
1257 		    host->host->host_no, acornscsi_target(host), transferred);
1258 	else if (transferred == 0)
1259 	    host->dma.xfer_setup = 0;
1260 	else {
1261 	    transferred += host->dma.start_addr;
1262 	    dmac_write(host, DMAC_TXADRLO, transferred);
1263 	    dmac_write(host, DMAC_TXADRMD, transferred >> 8);
1264 	    dmac_write(host, DMAC_TXADRHI, transferred >> 16);
1265 #if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
1266 	    DBG(host->SCpnt, acornscsi_dumpdma(host, "adjo"));
1267 #endif
1268 	}
1269     }
1270 }
1271 #endif
1272 
1273 /* =========================================================================================
1274  * Data I/O
1275  */
1276 static int
1277 acornscsi_write_pio(AS_Host *host, char *bytes, int *ptr, int len, unsigned int max_timeout)
1278 {
1279 	unsigned int asr, timeout = max_timeout;
1280 	int my_ptr = *ptr;
1281 
1282 	while (my_ptr < len) {
1283 		asr = sbic_arm_read(host, SBIC_ASR);
1284 
1285 		if (asr & ASR_DBR) {
1286 			timeout = max_timeout;
1287 
1288 			sbic_arm_write(host, SBIC_DATA, bytes[my_ptr++]);
1289 		} else if (asr & ASR_INT)
1290 			break;
1291 		else if (--timeout == 0)
1292 			break;
1293 		udelay(1);
1294 	}
1295 
1296 	*ptr = my_ptr;
1297 
1298 	return (timeout == 0) ? -1 : 0;
1299 }
1300 
1301 /*
1302  * Function: void acornscsi_sendcommand(AS_Host *host)
1303  * Purpose : send a command to a target
1304  * Params  : host - host which is connected to target
1305  */
1306 static void
1307 acornscsi_sendcommand(AS_Host *host)
1308 {
1309 	struct scsi_cmnd *SCpnt = host->SCpnt;
1310 
1311     sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1312     sbic_arm_writenext(host, 0);
1313     sbic_arm_writenext(host, SCpnt->cmd_len - host->scsi.SCp.sent_command);
1314 
1315     acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1316 
1317     if (acornscsi_write_pio(host, SCpnt->cmnd,
1318 	(int *)&host->scsi.SCp.sent_command, SCpnt->cmd_len, 1000000))
1319 	printk("scsi%d: timeout while sending command\n", host->host->host_no);
1320 
1321     host->scsi.phase = PHASE_COMMAND;
1322 }
1323 
1324 static
1325 void acornscsi_sendmessage(AS_Host *host)
1326 {
1327     unsigned int message_length = msgqueue_msglength(&host->scsi.msgs);
1328     unsigned int msgnr;
1329     struct message *msg;
1330 
1331 #if (DEBUG & DEBUG_MESSAGES)
1332     printk("scsi%d.%c: sending message ",
1333 	    host->host->host_no, acornscsi_target(host));
1334 #endif
1335 
1336     switch (message_length) {
1337     case 0:
1338 	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1339 
1340 	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 1");
1341 
1342 	sbic_arm_write(host, SBIC_DATA, NOP);
1343 
1344 	host->scsi.last_message = NOP;
1345 #if (DEBUG & DEBUG_MESSAGES)
1346 	printk("NOP");
1347 #endif
1348 	break;
1349 
1350     case 1:
1351 	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1352 	msg = msgqueue_getmsg(&host->scsi.msgs, 0);
1353 
1354 	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 2");
1355 
1356 	sbic_arm_write(host, SBIC_DATA, msg->msg[0]);
1357 
1358 	host->scsi.last_message = msg->msg[0];
1359 #if (DEBUG & DEBUG_MESSAGES)
1360 	spi_print_msg(msg->msg);
1361 #endif
1362 	break;
1363 
1364     default:
1365 	/*
1366 	 * ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.14)
1367 	 * 'When a target sends this (MESSAGE_REJECT) message, it
1368 	 *  shall change to MESSAGE IN phase and send this message
1369 	 *  prior to requesting additional message bytes from the
1370 	 *  initiator.  This provides an interlock so that the
1371 	 *  initiator can determine which message byte is rejected.
1372 	 */
1373 	sbic_arm_write(host, SBIC_TRANSCNTH, 0);
1374 	sbic_arm_writenext(host, 0);
1375 	sbic_arm_writenext(host, message_length);
1376 	acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1377 
1378 	msgnr = 0;
1379 	while ((msg = msgqueue_getmsg(&host->scsi.msgs, msgnr++)) != NULL) {
1380 	    unsigned int i;
1381 #if (DEBUG & DEBUG_MESSAGES)
1382 	    spi_print_msg(msg);
1383 #endif
1384 	    i = 0;
1385 	    if (acornscsi_write_pio(host, msg->msg, &i, msg->length, 1000000))
1386 		printk("scsi%d: timeout while sending message\n", host->host->host_no);
1387 
1388 	    host->scsi.last_message = msg->msg[0];
1389 	    if (msg->msg[0] == EXTENDED_MESSAGE)
1390 		host->scsi.last_message |= msg->msg[2] << 8;
1391 
1392 	    if (i != msg->length)
1393 		break;
1394 	}
1395 	break;
1396     }
1397 #if (DEBUG & DEBUG_MESSAGES)
1398     printk("\n");
1399 #endif
1400 }
1401 
1402 /*
1403  * Function: void acornscsi_readstatusbyte(AS_Host *host)
1404  * Purpose : Read status byte from connected target
1405  * Params  : host - host connected to target
1406  */
1407 static
1408 void acornscsi_readstatusbyte(AS_Host *host)
1409 {
1410     acornscsi_sbic_issuecmd(host, CMND_XFERINFO|CMND_SBT);
1411     acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "reading status byte");
1412     host->scsi.SCp.Status = sbic_arm_read(host, SBIC_DATA);
1413 }
1414 
1415 /*
1416  * Function: unsigned char acornscsi_readmessagebyte(AS_Host *host)
1417  * Purpose : Read one message byte from connected target
1418  * Params  : host - host connected to target
1419  */
1420 static
1421 unsigned char acornscsi_readmessagebyte(AS_Host *host)
1422 {
1423     unsigned char message;
1424 
1425     acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
1426 
1427     acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "for message byte");
1428 
1429     message = sbic_arm_read(host, SBIC_DATA);
1430 
1431     /* wait for MSGIN-XFER-PAUSED */
1432     acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after message byte");
1433 
1434     sbic_arm_read(host, SBIC_SSR);
1435 
1436     return message;
1437 }
1438 
1439 /*
1440  * Function: void acornscsi_message(AS_Host *host)
1441  * Purpose : Read complete message from connected target & action message
1442  * Params  : host - host connected to target
1443  */
1444 static
1445 void acornscsi_message(AS_Host *host)
1446 {
1447     unsigned char message[16];
1448     unsigned int msgidx = 0, msglen = 1;
1449 
1450     do {
1451 	message[msgidx] = acornscsi_readmessagebyte(host);
1452 
1453 	switch (msgidx) {
1454 	case 0:
1455 	    if (message[0] == EXTENDED_MESSAGE ||
1456 		(message[0] >= 0x20 && message[0] <= 0x2f))
1457 		msglen = 2;
1458 	    break;
1459 
1460 	case 1:
1461 	    if (message[0] == EXTENDED_MESSAGE)
1462 		msglen += message[msgidx];
1463 	    break;
1464 	}
1465 	msgidx += 1;
1466 	if (msgidx < msglen) {
1467 	    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1468 
1469 	    /* wait for next msg-in */
1470 	    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after negate ack");
1471 	    sbic_arm_read(host, SBIC_SSR);
1472 	}
1473     } while (msgidx < msglen);
1474 
1475 #if (DEBUG & DEBUG_MESSAGES)
1476     printk("scsi%d.%c: message in: ",
1477 	    host->host->host_no, acornscsi_target(host));
1478     spi_print_msg(message);
1479     printk("\n");
1480 #endif
1481 
1482     if (host->scsi.phase == PHASE_RECONNECTED) {
1483 	/*
1484 	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1485 	 * 'Whenever a target reconnects to an initiator to continue
1486 	 *  a tagged I/O process, the SIMPLE QUEUE TAG message shall
1487 	 *  be sent immediately following the IDENTIFY message...'
1488 	 */
1489 	if (message[0] == SIMPLE_QUEUE_TAG)
1490 	    host->scsi.reconnected.tag = message[1];
1491 	if (acornscsi_reconnect_finish(host))
1492 	    host->scsi.phase = PHASE_MSGIN;
1493     }
1494 
1495     switch (message[0]) {
1496     case ABORT:
1497     case ABORT_TAG:
1498     case COMMAND_COMPLETE:
1499 	if (host->scsi.phase != PHASE_STATUSIN) {
1500 	    printk(KERN_ERR "scsi%d.%c: command complete following non-status in phase?\n",
1501 		    host->host->host_no, acornscsi_target(host));
1502 	    acornscsi_dumplog(host, host->SCpnt->device->id);
1503 	}
1504 	host->scsi.phase = PHASE_DONE;
1505 	host->scsi.SCp.Message = message[0];
1506 	break;
1507 
1508     case SAVE_POINTERS:
1509 	/*
1510 	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.20)
1511 	 * 'The SAVE DATA POINTER message is sent from a target to
1512 	 *  direct the initiator to copy the active data pointer to
1513 	 *  the saved data pointer for the current I/O process.
1514 	 */
1515 	acornscsi_dma_cleanup(host);
1516 	host->SCpnt->SCp = host->scsi.SCp;
1517 	host->SCpnt->SCp.sent_command = 0;
1518 	host->scsi.phase = PHASE_MSGIN;
1519 	break;
1520 
1521     case RESTORE_POINTERS:
1522 	/*
1523 	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.19)
1524 	 * 'The RESTORE POINTERS message is sent from a target to
1525 	 *  direct the initiator to copy the most recently saved
1526 	 *  command, data, and status pointers for the I/O process
1527 	 *  to the corresponding active pointers.  The command and
1528 	 *  status pointers shall be restored to the beginning of
1529 	 *  the present command and status areas.'
1530 	 */
1531 	acornscsi_dma_cleanup(host);
1532 	host->scsi.SCp = host->SCpnt->SCp;
1533 	host->scsi.phase = PHASE_MSGIN;
1534 	break;
1535 
1536     case DISCONNECT:
1537 	/*
1538 	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 6.4.2)
1539 	 * 'On those occasions when an error or exception condition occurs
1540 	 *  and the target elects to repeat the information transfer, the
1541 	 *  target may repeat the transfer either issuing a RESTORE POINTERS
1542 	 *  message or by disconnecting without issuing a SAVE POINTERS
1543 	 *  message.  When reconnection is completed, the most recent
1544 	 *  saved pointer values are restored.'
1545 	 */
1546 	acornscsi_dma_cleanup(host);
1547 	host->scsi.phase = PHASE_DISCONNECT;
1548 	break;
1549 
1550     case MESSAGE_REJECT:
1551 #if 0 /* this isn't needed any more */
1552 	/*
1553 	 * If we were negociating sync transfer, we don't yet know if
1554 	 * this REJECT is for the sync transfer or for the tagged queue/wide
1555 	 * transfer.  Re-initiate sync transfer negotiation now, and if
1556 	 * we got a REJECT in response to SDTR, then it'll be set to DONE.
1557 	 */
1558 	if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST)
1559 	    host->device[host->SCpnt->device->id].sync_state = SYNC_NEGOCIATE;
1560 #endif
1561 
1562 	/*
1563 	 * If we have any messages waiting to go out, then assert ATN now
1564 	 */
1565 	if (msgqueue_msglength(&host->scsi.msgs))
1566 	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1567 
1568 	switch (host->scsi.last_message) {
1569 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1570 	case HEAD_OF_QUEUE_TAG:
1571 	case ORDERED_QUEUE_TAG:
1572 	case SIMPLE_QUEUE_TAG:
1573 	    /*
1574 	     * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
1575 	     *  If a target does not implement tagged queuing and a queue tag
1576 	     *  message is received, it shall respond with a MESSAGE REJECT
1577 	     *  message and accept the I/O process as if it were untagged.
1578 	     */
1579 	    printk(KERN_NOTICE "scsi%d.%c: disabling tagged queueing\n",
1580 		    host->host->host_no, acornscsi_target(host));
1581 	    host->SCpnt->device->simple_tags = 0;
1582 	    set_bit(host->SCpnt->device->id * 8 +
1583 		    (u8)(host->SCpnt->device->lun & 0x7), host->busyluns);
1584 	    break;
1585 #endif
1586 	case EXTENDED_MESSAGE | (EXTENDED_SDTR << 8):
1587 	    /*
1588 	     * Target can't handle synchronous transfers
1589 	     */
1590 	    printk(KERN_NOTICE "scsi%d.%c: Using asynchronous transfer\n",
1591 		    host->host->host_no, acornscsi_target(host));
1592 	    host->device[host->SCpnt->device->id].sync_xfer = SYNCHTRANSFER_2DBA;
1593 	    host->device[host->SCpnt->device->id].sync_state = SYNC_ASYNCHRONOUS;
1594 	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1595 	    break;
1596 
1597 	default:
1598 	    break;
1599 	}
1600 	break;
1601 
1602     case QUEUE_FULL:
1603 	/* TODO: target queue is full */
1604 	break;
1605 
1606     case SIMPLE_QUEUE_TAG:
1607 	/* tag queue reconnect... message[1] = queue tag.  Print something to indicate something happened! */
1608 	printk("scsi%d.%c: reconnect queue tag %02X\n",
1609 		host->host->host_no, acornscsi_target(host),
1610 		message[1]);
1611 	break;
1612 
1613     case EXTENDED_MESSAGE:
1614 	switch (message[2]) {
1615 #ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1616 	case EXTENDED_SDTR:
1617 	    if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST) {
1618 		/*
1619 		 * We requested synchronous transfers.  This isn't quite right...
1620 		 * We can only say if this succeeded if we proceed on to execute the
1621 		 * command from this message.  If we get a MESSAGE PARITY ERROR,
1622 		 * and the target retries fail, then we fallback to asynchronous mode
1623 		 */
1624 		host->device[host->SCpnt->device->id].sync_state = SYNC_COMPLETED;
1625 		printk(KERN_NOTICE "scsi%d.%c: Using synchronous transfer, offset %d, %d ns\n",
1626 			host->host->host_no, acornscsi_target(host),
1627 			message[4], message[3] * 4);
1628 		host->device[host->SCpnt->device->id].sync_xfer =
1629 			calc_sync_xfer(message[3] * 4, message[4]);
1630 	    } else {
1631 		unsigned char period, length;
1632 		/*
1633 		 * Target requested synchronous transfers.  The agreement is only
1634 		 * to be in operation AFTER the target leaves message out phase.
1635 		 */
1636 		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1637 		period = max_t(unsigned int, message[3], sdtr_period / 4);
1638 		length = min_t(unsigned int, message[4], sdtr_size);
1639 		msgqueue_addmsg(&host->scsi.msgs, 5, EXTENDED_MESSAGE, 3,
1640 				 EXTENDED_SDTR, period, length);
1641 		host->device[host->SCpnt->device->id].sync_xfer =
1642 			calc_sync_xfer(period * 4, length);
1643 	    }
1644 	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1645 	    break;
1646 #else
1647 	    /* We do not accept synchronous transfers.  Respond with a
1648 	     * MESSAGE_REJECT.
1649 	     */
1650 #endif
1651 
1652 	case EXTENDED_WDTR:
1653 	    /* The WD33C93A is only 8-bit.  We respond with a MESSAGE_REJECT
1654 	     * to a wide data transfer request.
1655 	     */
1656 	default:
1657 	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1658 	    msgqueue_flush(&host->scsi.msgs);
1659 	    msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1660 	    break;
1661 	}
1662 	break;
1663 
1664     default: /* reject message */
1665 	printk(KERN_ERR "scsi%d.%c: unrecognised message %02X, rejecting\n",
1666 		host->host->host_no, acornscsi_target(host),
1667 		message[0]);
1668 	acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
1669 	msgqueue_flush(&host->scsi.msgs);
1670 	msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
1671 	host->scsi.phase = PHASE_MSGIN;
1672 	break;
1673     }
1674     acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1675 }
1676 
1677 /*
1678  * Function: int acornscsi_buildmessages(AS_Host *host)
1679  * Purpose : build the connection messages for a host
1680  * Params  : host - host to add messages to
1681  */
1682 static
1683 void acornscsi_buildmessages(AS_Host *host)
1684 {
1685 #if 0
1686     /* does the device need resetting? */
1687     if (cmd_reset) {
1688 	msgqueue_addmsg(&host->scsi.msgs, 1, BUS_DEVICE_RESET);
1689 	return;
1690     }
1691 #endif
1692 
1693     msgqueue_addmsg(&host->scsi.msgs, 1,
1694 		     IDENTIFY(host->device[host->SCpnt->device->id].disconnect_ok,
1695 			     host->SCpnt->device->lun));
1696 
1697 #if 0
1698     /* does the device need the current command aborted */
1699     if (cmd_aborted) {
1700 	acornscsi_abortcmd(host->SCpnt->tag);
1701 	return;
1702     }
1703 #endif
1704 
1705 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1706     if (host->SCpnt->tag) {
1707 	unsigned int tag_type;
1708 
1709 	if (host->SCpnt->cmnd[0] == REQUEST_SENSE ||
1710 	    host->SCpnt->cmnd[0] == TEST_UNIT_READY ||
1711 	    host->SCpnt->cmnd[0] == INQUIRY)
1712 	    tag_type = HEAD_OF_QUEUE_TAG;
1713 	else
1714 	    tag_type = SIMPLE_QUEUE_TAG;
1715 	msgqueue_addmsg(&host->scsi.msgs, 2, tag_type, host->SCpnt->tag);
1716     }
1717 #endif
1718 
1719 #ifdef CONFIG_SCSI_ACORNSCSI_SYNC
1720     if (host->device[host->SCpnt->device->id].sync_state == SYNC_NEGOCIATE) {
1721 	host->device[host->SCpnt->device->id].sync_state = SYNC_SENT_REQUEST;
1722 	msgqueue_addmsg(&host->scsi.msgs, 5,
1723 			 EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
1724 			 sdtr_period / 4, sdtr_size);
1725     }
1726 #endif
1727 }
1728 
1729 /*
1730  * Function: int acornscsi_starttransfer(AS_Host *host)
1731  * Purpose : transfer data to/from connected target
1732  * Params  : host - host to which target is connected
1733  * Returns : 0 if failure
1734  */
1735 static
1736 int acornscsi_starttransfer(AS_Host *host)
1737 {
1738     int residual;
1739 
1740     if (!host->scsi.SCp.ptr /*&& host->scsi.SCp.this_residual*/) {
1741 	printk(KERN_ERR "scsi%d.%c: null buffer passed to acornscsi_starttransfer\n",
1742 		host->host->host_no, acornscsi_target(host));
1743 	return 0;
1744     }
1745 
1746     residual = scsi_bufflen(host->SCpnt) - host->scsi.SCp.scsi_xferred;
1747 
1748     sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
1749     sbic_arm_writenext(host, residual >> 16);
1750     sbic_arm_writenext(host, residual >> 8);
1751     sbic_arm_writenext(host, residual);
1752     acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
1753     return 1;
1754 }
1755 
1756 /* =========================================================================================
1757  * Connection & Disconnection
1758  */
1759 /*
1760  * Function : acornscsi_reconnect(AS_Host *host)
1761  * Purpose  : reconnect a previously disconnected command
1762  * Params   : host - host specific data
1763  * Remarks  : SCSI spec says:
1764  *		'The set of active pointers is restored from the set
1765  *		 of saved pointers upon reconnection of the I/O process'
1766  */
1767 static
1768 int acornscsi_reconnect(AS_Host *host)
1769 {
1770     unsigned int target, lun, ok = 0;
1771 
1772     target = sbic_arm_read(host, SBIC_SOURCEID);
1773 
1774     if (!(target & 8))
1775 	printk(KERN_ERR "scsi%d: invalid source id after reselection "
1776 		"- device fault?\n",
1777 		host->host->host_no);
1778 
1779     target &= 7;
1780 
1781     if (host->SCpnt && !host->scsi.disconnectable) {
1782 	printk(KERN_ERR "scsi%d.%d: reconnected while command in "
1783 		"progress to target %d?\n",
1784 		host->host->host_no, target, host->SCpnt->device->id);
1785 	host->SCpnt = NULL;
1786     }
1787 
1788     lun = sbic_arm_read(host, SBIC_DATA) & 7;
1789 
1790     host->scsi.reconnected.target = target;
1791     host->scsi.reconnected.lun = lun;
1792     host->scsi.reconnected.tag = 0;
1793 
1794     if (host->scsi.disconnectable && host->SCpnt &&
1795 	host->SCpnt->device->id == target && host->SCpnt->device->lun == lun)
1796 	ok = 1;
1797 
1798     if (!ok && queue_probetgtlun(&host->queues.disconnected, target, lun))
1799 	ok = 1;
1800 
1801     ADD_STATUS(target, 0x81, host->scsi.phase, 0);
1802 
1803     if (ok) {
1804 	host->scsi.phase = PHASE_RECONNECTED;
1805     } else {
1806 	/* this doesn't seem to work */
1807 	printk(KERN_ERR "scsi%d.%c: reselected with no command "
1808 		"to reconnect with\n",
1809 		host->host->host_no, '0' + target);
1810 	acornscsi_dumplog(host, target);
1811 	acornscsi_abortcmd(host, 0);
1812 	if (host->SCpnt) {
1813 	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1814 	    host->SCpnt = NULL;
1815 	}
1816     }
1817     acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
1818     return !ok;
1819 }
1820 
1821 /*
1822  * Function: int acornscsi_reconect_finish(AS_Host *host)
1823  * Purpose : finish reconnecting a command
1824  * Params  : host - host to complete
1825  * Returns : 0 if failed
1826  */
1827 static
1828 int acornscsi_reconnect_finish(AS_Host *host)
1829 {
1830     if (host->scsi.disconnectable && host->SCpnt) {
1831 	host->scsi.disconnectable = 0;
1832 	if (host->SCpnt->device->id  == host->scsi.reconnected.target &&
1833 	    host->SCpnt->device->lun == host->scsi.reconnected.lun &&
1834 	    host->SCpnt->tag         == host->scsi.reconnected.tag) {
1835 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1836 	    DBG(host->SCpnt, printk("scsi%d.%c: reconnected",
1837 		    host->host->host_no, acornscsi_target(host)));
1838 #endif
1839 	} else {
1840 	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
1841 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1842 	    DBG(host->SCpnt, printk("scsi%d.%c: had to move command "
1843 		    "to disconnected queue\n",
1844 		    host->host->host_no, acornscsi_target(host)));
1845 #endif
1846 	    host->SCpnt = NULL;
1847 	}
1848     }
1849     if (!host->SCpnt) {
1850 	host->SCpnt = queue_remove_tgtluntag(&host->queues.disconnected,
1851 				host->scsi.reconnected.target,
1852 				host->scsi.reconnected.lun,
1853 				host->scsi.reconnected.tag);
1854 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1855 	DBG(host->SCpnt, printk("scsi%d.%c: had to get command",
1856 		host->host->host_no, acornscsi_target(host)));
1857 #endif
1858     }
1859 
1860     if (!host->SCpnt)
1861 	acornscsi_abortcmd(host, host->scsi.reconnected.tag);
1862     else {
1863 	/*
1864 	 * Restore data pointer from SAVED pointers.
1865 	 */
1866 	host->scsi.SCp = host->SCpnt->SCp;
1867 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1868 	printk(", data pointers: [%p, %X]",
1869 		host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
1870 #endif
1871     }
1872 #if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
1873     printk("\n");
1874 #endif
1875 
1876     host->dma.transferred = host->scsi.SCp.scsi_xferred;
1877 
1878     return host->SCpnt != NULL;
1879 }
1880 
1881 /*
1882  * Function: void acornscsi_disconnect_unexpected(AS_Host *host)
1883  * Purpose : handle an unexpected disconnect
1884  * Params  : host - host on which disconnect occurred
1885  */
1886 static
1887 void acornscsi_disconnect_unexpected(AS_Host *host)
1888 {
1889     printk(KERN_ERR "scsi%d.%c: unexpected disconnect\n",
1890 	    host->host->host_no, acornscsi_target(host));
1891 #if (DEBUG & DEBUG_ABORT)
1892     acornscsi_dumplog(host, 8);
1893 #endif
1894 
1895     acornscsi_done(host, &host->SCpnt, DID_ERROR);
1896 }
1897 
1898 /*
1899  * Function: void acornscsi_abortcmd(AS_host *host, unsigned char tag)
1900  * Purpose : abort a currently executing command
1901  * Params  : host - host with connected command to abort
1902  *	     tag  - tag to abort
1903  */
1904 static
1905 void acornscsi_abortcmd(AS_Host *host, unsigned char tag)
1906 {
1907     host->scsi.phase = PHASE_ABORTED;
1908     sbic_arm_write(host, SBIC_CMND, CMND_ASSERTATN);
1909 
1910     msgqueue_flush(&host->scsi.msgs);
1911 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
1912     if (tag)
1913 	msgqueue_addmsg(&host->scsi.msgs, 2, ABORT_TAG, tag);
1914     else
1915 #endif
1916 	msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
1917 }
1918 
1919 /* ==========================================================================================
1920  * Interrupt routines.
1921  */
1922 /*
1923  * Function: int acornscsi_sbicintr(AS_Host *host)
1924  * Purpose : handle interrupts from SCSI device
1925  * Params  : host - host to process
1926  * Returns : INTR_PROCESS if expecting another SBIC interrupt
1927  *	     INTR_IDLE if no interrupt
1928  *	     INTR_NEXT_COMMAND if we have finished processing the command
1929  */
1930 static
1931 intr_ret_t acornscsi_sbicintr(AS_Host *host, int in_irq)
1932 {
1933     unsigned int asr, ssr;
1934 
1935     asr = sbic_arm_read(host, SBIC_ASR);
1936     if (!(asr & ASR_INT))
1937 	return INTR_IDLE;
1938 
1939     ssr = sbic_arm_read(host, SBIC_SSR);
1940 
1941 #if (DEBUG & DEBUG_PHASES)
1942     print_sbic_status(asr, ssr, host->scsi.phase);
1943 #endif
1944 
1945     ADD_STATUS(8, ssr, host->scsi.phase, in_irq);
1946 
1947     if (host->SCpnt && !host->scsi.disconnectable)
1948 	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
1949 
1950     switch (ssr) {
1951     case 0x00:				/* reset state - not advanced			*/
1952 	printk(KERN_ERR "scsi%d: reset in standard mode but wanted advanced mode.\n",
1953 		host->host->host_no);
1954 	/* setup sbic - WD33C93A */
1955 	sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
1956 	sbic_arm_write(host, SBIC_CMND, CMND_RESET);
1957 	return INTR_IDLE;
1958 
1959     case 0x01:				/* reset state - advanced			*/
1960 	sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
1961 	sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
1962 	sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
1963 	sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
1964 	msgqueue_flush(&host->scsi.msgs);
1965 	return INTR_IDLE;
1966 
1967     case 0x41:				/* unexpected disconnect aborted command	*/
1968 	acornscsi_disconnect_unexpected(host);
1969 	return INTR_NEXT_COMMAND;
1970     }
1971 
1972     switch (host->scsi.phase) {
1973     case PHASE_CONNECTING:		/* STATE: command removed from issue queue	*/
1974 	switch (ssr) {
1975 	case 0x11:			/* -> PHASE_CONNECTED				*/
1976 	    /* BUS FREE -> SELECTION */
1977 	    host->scsi.phase = PHASE_CONNECTED;
1978 	    msgqueue_flush(&host->scsi.msgs);
1979 	    host->dma.transferred = host->scsi.SCp.scsi_xferred;
1980 	    /* 33C93 gives next interrupt indicating bus phase */
1981 	    asr = sbic_arm_read(host, SBIC_ASR);
1982 	    if (!(asr & ASR_INT))
1983 		break;
1984 	    ssr = sbic_arm_read(host, SBIC_SSR);
1985 	    ADD_STATUS(8, ssr, host->scsi.phase, 1);
1986 	    ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, 1);
1987 	    goto connected;
1988 
1989 	case 0x42:			/* select timed out				*/
1990 					/* -> PHASE_IDLE				*/
1991 	    acornscsi_done(host, &host->SCpnt, DID_NO_CONNECT);
1992 	    return INTR_NEXT_COMMAND;
1993 
1994 	case 0x81:			/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
1995 	    /* BUS FREE -> RESELECTION */
1996 	    host->origSCpnt = host->SCpnt;
1997 	    host->SCpnt = NULL;
1998 	    msgqueue_flush(&host->scsi.msgs);
1999 	    acornscsi_reconnect(host);
2000 	    break;
2001 
2002 	default:
2003 	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTING, SSR %02X?\n",
2004 		    host->host->host_no, acornscsi_target(host), ssr);
2005 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2006 	    acornscsi_abortcmd(host, host->SCpnt->tag);
2007 	}
2008 	return INTR_PROCESSING;
2009 
2010     connected:
2011     case PHASE_CONNECTED:		/* STATE: device selected ok			*/
2012 	switch (ssr) {
2013 #ifdef NONSTANDARD
2014 	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2015 	    /* SELECTION -> COMMAND */
2016 	    acornscsi_sendcommand(host);
2017 	    break;
2018 
2019 	case 0x8b:			/* -> PHASE_STATUS				*/
2020 	    /* SELECTION -> STATUS */
2021 	    acornscsi_readstatusbyte(host);
2022 	    host->scsi.phase = PHASE_STATUSIN;
2023 	    break;
2024 #endif
2025 
2026 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2027 	    /* SELECTION ->MESSAGE OUT */
2028 	    host->scsi.phase = PHASE_MSGOUT;
2029 	    acornscsi_buildmessages(host);
2030 	    acornscsi_sendmessage(host);
2031 	    break;
2032 
2033 	/* these should not happen */
2034 	case 0x85:			/* target disconnected				*/
2035 	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2036 	    break;
2037 
2038 	default:
2039 	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTED, SSR %02X?\n",
2040 		    host->host->host_no, acornscsi_target(host), ssr);
2041 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2042 	    acornscsi_abortcmd(host, host->SCpnt->tag);
2043 	}
2044 	return INTR_PROCESSING;
2045 
2046     case PHASE_MSGOUT:			/* STATE: connected & sent IDENTIFY message	*/
2047 	/*
2048 	 * SCSI standard says that MESSAGE OUT phases can be followed by a
2049 	 * DATA phase, STATUS phase, MESSAGE IN phase or COMMAND phase
2050 	 */
2051 	switch (ssr) {
2052 	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2053 	case 0x1a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2054 	    /* MESSAGE OUT -> COMMAND */
2055 	    acornscsi_sendcommand(host);
2056 	    break;
2057 
2058 	case 0x8b:			/* -> PHASE_STATUS				*/
2059 	case 0x1b:			/* -> PHASE_STATUS				*/
2060 	    /* MESSAGE OUT -> STATUS */
2061 	    acornscsi_readstatusbyte(host);
2062 	    host->scsi.phase = PHASE_STATUSIN;
2063 	    break;
2064 
2065 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2066 	    /* MESSAGE_OUT(MESSAGE_IN) ->MESSAGE OUT */
2067 	    acornscsi_sendmessage(host);
2068 	    break;
2069 
2070 	case 0x4f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2071 	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2072 	    /* MESSAGE OUT -> MESSAGE IN */
2073 	    acornscsi_message(host);
2074 	    break;
2075 
2076 	default:
2077 	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGOUT, SSR %02X?\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_PROCESSING;
2082 
2083     case PHASE_COMMAND: 		/* STATE: connected & command sent		*/
2084 	switch (ssr) {
2085 	case 0x18:			/* -> PHASE_DATAOUT				*/
2086 	    /* COMMAND -> DATA OUT */
2087 	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2088 		acornscsi_abortcmd(host, host->SCpnt->tag);
2089 	    acornscsi_dma_setup(host, DMA_OUT);
2090 	    if (!acornscsi_starttransfer(host))
2091 		acornscsi_abortcmd(host, host->SCpnt->tag);
2092 	    host->scsi.phase = PHASE_DATAOUT;
2093 	    return INTR_IDLE;
2094 
2095 	case 0x19:			/* -> PHASE_DATAIN				*/
2096 	    /* COMMAND -> DATA IN */
2097 	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
2098 		acornscsi_abortcmd(host, host->SCpnt->tag);
2099 	    acornscsi_dma_setup(host, DMA_IN);
2100 	    if (!acornscsi_starttransfer(host))
2101 		acornscsi_abortcmd(host, host->SCpnt->tag);
2102 	    host->scsi.phase = PHASE_DATAIN;
2103 	    return INTR_IDLE;
2104 
2105 	case 0x1b:			/* -> PHASE_STATUS				*/
2106 	    /* COMMAND -> STATUS */
2107 	    acornscsi_readstatusbyte(host);
2108 	    host->scsi.phase = PHASE_STATUSIN;
2109 	    break;
2110 
2111 	case 0x1e:			/* -> PHASE_MSGOUT				*/
2112 	    /* COMMAND -> MESSAGE OUT */
2113 	    acornscsi_sendmessage(host);
2114 	    break;
2115 
2116 	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2117 	    /* COMMAND -> MESSAGE IN */
2118 	    acornscsi_message(host);
2119 	    break;
2120 
2121 	default:
2122 	    printk(KERN_ERR "scsi%d.%c: PHASE_COMMAND, SSR %02X?\n",
2123 		    host->host->host_no, acornscsi_target(host), ssr);
2124 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2125 	}
2126 	return INTR_PROCESSING;
2127 
2128     case PHASE_DISCONNECT:		/* STATE: connected, received DISCONNECT msg	*/
2129 	if (ssr == 0x85) {		/* -> PHASE_IDLE				*/
2130 	    host->scsi.disconnectable = 1;
2131 	    host->scsi.reconnected.tag = 0;
2132 	    host->scsi.phase = PHASE_IDLE;
2133 	    host->stats.disconnects += 1;
2134 	} else {
2135 	    printk(KERN_ERR "scsi%d.%c: PHASE_DISCONNECT, SSR %02X instead of disconnect?\n",
2136 		    host->host->host_no, acornscsi_target(host), ssr);
2137 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2138 	}
2139 	return INTR_NEXT_COMMAND;
2140 
2141     case PHASE_IDLE:			/* STATE: disconnected				*/
2142 	if (ssr == 0x81)		/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
2143 	    acornscsi_reconnect(host);
2144 	else {
2145 	    printk(KERN_ERR "scsi%d.%c: PHASE_IDLE, SSR %02X while idle?\n",
2146 		    host->host->host_no, acornscsi_target(host), ssr);
2147 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2148 	}
2149 	return INTR_PROCESSING;
2150 
2151     case PHASE_RECONNECTED:		/* STATE: device reconnected to initiator	*/
2152 	/*
2153 	 * Command reconnected - if MESGIN, get message - it may be
2154 	 * the tag.  If not, get command out of disconnected queue
2155 	 */
2156 	/*
2157 	 * If we reconnected and we're not in MESSAGE IN phase after IDENTIFY,
2158 	 * reconnect I_T_L command
2159 	 */
2160 	if (ssr != 0x8f && !acornscsi_reconnect_finish(host))
2161 	    return INTR_IDLE;
2162 	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
2163 	switch (ssr) {
2164 	case 0x88:			/* data out phase				*/
2165 					/* -> PHASE_DATAOUT				*/
2166 	    /* MESSAGE IN -> DATA OUT */
2167 	    acornscsi_dma_setup(host, DMA_OUT);
2168 	    if (!acornscsi_starttransfer(host))
2169 		acornscsi_abortcmd(host, host->SCpnt->tag);
2170 	    host->scsi.phase = PHASE_DATAOUT;
2171 	    return INTR_IDLE;
2172 
2173 	case 0x89:			/* data in phase				*/
2174 					/* -> PHASE_DATAIN				*/
2175 	    /* MESSAGE IN -> DATA IN */
2176 	    acornscsi_dma_setup(host, DMA_IN);
2177 	    if (!acornscsi_starttransfer(host))
2178 		acornscsi_abortcmd(host, host->SCpnt->tag);
2179 	    host->scsi.phase = PHASE_DATAIN;
2180 	    return INTR_IDLE;
2181 
2182 	case 0x8a:			/* command out					*/
2183 	    /* MESSAGE IN -> COMMAND */
2184 	    acornscsi_sendcommand(host);/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
2185 	    break;
2186 
2187 	case 0x8b:			/* status in					*/
2188 					/* -> PHASE_STATUSIN				*/
2189 	    /* MESSAGE IN -> STATUS */
2190 	    acornscsi_readstatusbyte(host);
2191 	    host->scsi.phase = PHASE_STATUSIN;
2192 	    break;
2193 
2194 	case 0x8e:			/* message out					*/
2195 					/* -> PHASE_MSGOUT				*/
2196 	    /* MESSAGE IN -> MESSAGE OUT */
2197 	    acornscsi_sendmessage(host);
2198 	    break;
2199 
2200 	case 0x8f:			/* message in					*/
2201 	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2202 	    break;
2203 
2204 	default:
2205 	    printk(KERN_ERR "scsi%d.%c: PHASE_RECONNECTED, SSR %02X after reconnect?\n",
2206 		    host->host->host_no, acornscsi_target(host), ssr);
2207 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2208 	}
2209 	return INTR_PROCESSING;
2210 
2211     case PHASE_DATAIN:			/* STATE: transferred data in			*/
2212 	/*
2213 	 * This is simple - if we disconnect then the DMA address & count is
2214 	 * correct.
2215 	 */
2216 	switch (ssr) {
2217 	case 0x19:			/* -> PHASE_DATAIN				*/
2218 	case 0x89:			/* -> PHASE_DATAIN				*/
2219 	    acornscsi_abortcmd(host, host->SCpnt->tag);
2220 	    return INTR_IDLE;
2221 
2222 	case 0x1b:			/* -> PHASE_STATUSIN				*/
2223 	case 0x4b:			/* -> PHASE_STATUSIN				*/
2224 	case 0x8b:			/* -> PHASE_STATUSIN				*/
2225 	    /* DATA IN -> STATUS */
2226 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2227 					  acornscsi_sbic_xfcount(host);
2228 	    acornscsi_dma_stop(host);
2229 	    acornscsi_readstatusbyte(host);
2230 	    host->scsi.phase = PHASE_STATUSIN;
2231 	    break;
2232 
2233 	case 0x1e:			/* -> PHASE_MSGOUT				*/
2234 	case 0x4e:			/* -> PHASE_MSGOUT				*/
2235 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2236 	    /* DATA IN -> MESSAGE OUT */
2237 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2238 					  acornscsi_sbic_xfcount(host);
2239 	    acornscsi_dma_stop(host);
2240 	    acornscsi_sendmessage(host);
2241 	    break;
2242 
2243 	case 0x1f:			/* message in					*/
2244 	case 0x4f:			/* message in					*/
2245 	case 0x8f:			/* message in					*/
2246 	    /* DATA IN -> MESSAGE IN */
2247 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2248 					  acornscsi_sbic_xfcount(host);
2249 	    acornscsi_dma_stop(host);
2250 	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2251 	    break;
2252 
2253 	default:
2254 	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAIN, SSR %02X?\n",
2255 		    host->host->host_no, acornscsi_target(host), ssr);
2256 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2257 	}
2258 	return INTR_PROCESSING;
2259 
2260     case PHASE_DATAOUT: 		/* STATE: transferred data out			*/
2261 	/*
2262 	 * This is more complicated - if we disconnect, the DMA could be 12
2263 	 * bytes ahead of us.  We need to correct this.
2264 	 */
2265 	switch (ssr) {
2266 	case 0x18:			/* -> PHASE_DATAOUT				*/
2267 	case 0x88:			/* -> PHASE_DATAOUT				*/
2268 	    acornscsi_abortcmd(host, host->SCpnt->tag);
2269 	    return INTR_IDLE;
2270 
2271 	case 0x1b:			/* -> PHASE_STATUSIN				*/
2272 	case 0x4b:			/* -> PHASE_STATUSIN				*/
2273 	case 0x8b:			/* -> PHASE_STATUSIN				*/
2274 	    /* DATA OUT -> STATUS */
2275 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2276 					  acornscsi_sbic_xfcount(host);
2277 	    acornscsi_dma_stop(host);
2278 	    acornscsi_dma_adjust(host);
2279 	    acornscsi_readstatusbyte(host);
2280 	    host->scsi.phase = PHASE_STATUSIN;
2281 	    break;
2282 
2283 	case 0x1e:			/* -> PHASE_MSGOUT				*/
2284 	case 0x4e:			/* -> PHASE_MSGOUT				*/
2285 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2286 	    /* DATA OUT -> MESSAGE OUT */
2287 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2288 					  acornscsi_sbic_xfcount(host);
2289 	    acornscsi_dma_stop(host);
2290 	    acornscsi_dma_adjust(host);
2291 	    acornscsi_sendmessage(host);
2292 	    break;
2293 
2294 	case 0x1f:			/* message in					*/
2295 	case 0x4f:			/* message in					*/
2296 	case 0x8f:			/* message in					*/
2297 	    /* DATA OUT -> MESSAGE IN */
2298 	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
2299 					  acornscsi_sbic_xfcount(host);
2300 	    acornscsi_dma_stop(host);
2301 	    acornscsi_dma_adjust(host);
2302 	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
2303 	    break;
2304 
2305 	default:
2306 	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAOUT, SSR %02X?\n",
2307 		    host->host->host_no, acornscsi_target(host), ssr);
2308 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2309 	}
2310 	return INTR_PROCESSING;
2311 
2312     case PHASE_STATUSIN:		/* STATE: status in complete			*/
2313 	switch (ssr) {
2314 	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2315 	case 0x8f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2316 	    /* STATUS -> MESSAGE IN */
2317 	    acornscsi_message(host);
2318 	    break;
2319 
2320 	case 0x1e:			/* -> PHASE_MSGOUT				*/
2321 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2322 	    /* STATUS -> MESSAGE OUT */
2323 	    acornscsi_sendmessage(host);
2324 	    break;
2325 
2326 	default:
2327 	    printk(KERN_ERR "scsi%d.%c: PHASE_STATUSIN, SSR %02X instead of MESSAGE_IN?\n",
2328 		    host->host->host_no, acornscsi_target(host), ssr);
2329 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2330 	}
2331 	return INTR_PROCESSING;
2332 
2333     case PHASE_MSGIN:			/* STATE: message in				*/
2334 	switch (ssr) {
2335 	case 0x1e:			/* -> PHASE_MSGOUT				*/
2336 	case 0x4e:			/* -> PHASE_MSGOUT				*/
2337 	case 0x8e:			/* -> PHASE_MSGOUT				*/
2338 	    /* MESSAGE IN -> MESSAGE OUT */
2339 	    acornscsi_sendmessage(host);
2340 	    break;
2341 
2342 	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
2343 	case 0x2f:
2344 	case 0x4f:
2345 	case 0x8f:
2346 	    acornscsi_message(host);
2347 	    break;
2348 
2349 	case 0x85:
2350 	    printk("scsi%d.%c: strange message in disconnection\n",
2351 		host->host->host_no, acornscsi_target(host));
2352 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2353 	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
2354 	    break;
2355 
2356 	default:
2357 	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGIN, SSR %02X after message in?\n",
2358 		    host->host->host_no, acornscsi_target(host), ssr);
2359 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2360 	}
2361 	return INTR_PROCESSING;
2362 
2363     case PHASE_DONE:			/* STATE: received status & message		*/
2364 	switch (ssr) {
2365 	case 0x85:			/* -> PHASE_IDLE				*/
2366 	    acornscsi_done(host, &host->SCpnt, DID_OK);
2367 	    return INTR_NEXT_COMMAND;
2368 
2369 	case 0x1e:
2370 	case 0x8e:
2371 	    acornscsi_sendmessage(host);
2372 	    break;
2373 
2374 	default:
2375 	    printk(KERN_ERR "scsi%d.%c: PHASE_DONE, SSR %02X instead of disconnect?\n",
2376 		    host->host->host_no, acornscsi_target(host), ssr);
2377 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2378 	}
2379 	return INTR_PROCESSING;
2380 
2381     case PHASE_ABORTED:
2382 	switch (ssr) {
2383 	case 0x85:
2384 	    if (host->SCpnt)
2385 		acornscsi_done(host, &host->SCpnt, DID_ABORT);
2386 	    else {
2387 		clear_bit(host->scsi.reconnected.target * 8 + host->scsi.reconnected.lun,
2388 			  host->busyluns);
2389 		host->scsi.phase = PHASE_IDLE;
2390 	    }
2391 	    return INTR_NEXT_COMMAND;
2392 
2393 	case 0x1e:
2394 	case 0x2e:
2395 	case 0x4e:
2396 	case 0x8e:
2397 	    acornscsi_sendmessage(host);
2398 	    break;
2399 
2400 	default:
2401 	    printk(KERN_ERR "scsi%d.%c: PHASE_ABORTED, SSR %02X?\n",
2402 		    host->host->host_no, acornscsi_target(host), ssr);
2403 	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2404 	}
2405 	return INTR_PROCESSING;
2406 
2407     default:
2408 	printk(KERN_ERR "scsi%d.%c: unknown driver phase %d\n",
2409 		host->host->host_no, acornscsi_target(host), ssr);
2410 	acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
2411     }
2412     return INTR_PROCESSING;
2413 }
2414 
2415 /*
2416  * Prototype: void acornscsi_intr(int irq, void *dev_id)
2417  * Purpose  : handle interrupts from Acorn SCSI card
2418  * Params   : irq    - interrupt number
2419  *	      dev_id - device specific data (AS_Host structure)
2420  */
2421 static irqreturn_t
2422 acornscsi_intr(int irq, void *dev_id)
2423 {
2424     AS_Host *host = (AS_Host *)dev_id;
2425     intr_ret_t ret;
2426     int iostatus;
2427     int in_irq = 0;
2428 
2429     do {
2430 	ret = INTR_IDLE;
2431 
2432 	iostatus = readb(host->fast + INT_REG);
2433 
2434 	if (iostatus & 2) {
2435 	    acornscsi_dma_intr(host);
2436 	    iostatus = readb(host->fast + INT_REG);
2437 	}
2438 
2439 	if (iostatus & 8)
2440 	    ret = acornscsi_sbicintr(host, in_irq);
2441 
2442 	/*
2443 	 * If we have a transfer pending, start it.
2444 	 * Only start it if the interface has already started transferring
2445 	 * it's data
2446 	 */
2447 	if (host->dma.xfer_required)
2448 	    acornscsi_dma_xfer(host);
2449 
2450 	if (ret == INTR_NEXT_COMMAND)
2451 	    ret = acornscsi_kick(host);
2452 
2453 	in_irq = 1;
2454     } while (ret != INTR_IDLE);
2455 
2456     return IRQ_HANDLED;
2457 }
2458 
2459 /*=============================================================================================
2460  * Interfaces between interrupt handler and rest of scsi code
2461  */
2462 
2463 /*
2464  * Function : acornscsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2465  * Purpose  : queues a SCSI command
2466  * Params   : cmd  - SCSI command
2467  *	      done - function called on completion, with pointer to command descriptor
2468  * Returns  : 0, or < 0 on error.
2469  */
2470 static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt,
2471 		       void (*done)(struct scsi_cmnd *))
2472 {
2473     AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2474 
2475     if (!done) {
2476 	/* there should be some way of rejecting errors like this without panicing... */
2477 	panic("scsi%d: queuecommand called with NULL done function [cmd=%p]",
2478 		host->host->host_no, SCpnt);
2479 	return -EINVAL;
2480     }
2481 
2482 #if (DEBUG & DEBUG_NO_WRITE)
2483     if (acornscsi_cmdtype(SCpnt->cmnd[0]) == CMD_WRITE && (NO_WRITE & (1 << SCpnt->device->id))) {
2484 	printk(KERN_CRIT "scsi%d.%c: WRITE attempted with NO_WRITE flag set\n",
2485 	    host->host->host_no, '0' + SCpnt->device->id);
2486 	SCpnt->result = DID_NO_CONNECT << 16;
2487 	done(SCpnt);
2488 	return 0;
2489     }
2490 #endif
2491 
2492     SCpnt->scsi_done = done;
2493     SCpnt->host_scribble = NULL;
2494     SCpnt->result = 0;
2495     SCpnt->tag = 0;
2496     SCpnt->SCp.phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
2497     SCpnt->SCp.sent_command = 0;
2498     SCpnt->SCp.scsi_xferred = 0;
2499 
2500     init_SCp(SCpnt);
2501 
2502     host->stats.queues += 1;
2503 
2504     {
2505 	unsigned long flags;
2506 
2507 	if (!queue_add_cmd_ordered(&host->queues.issue, SCpnt)) {
2508 	    SCpnt->result = DID_ERROR << 16;
2509 	    done(SCpnt);
2510 	    return 0;
2511 	}
2512 	local_irq_save(flags);
2513 	if (host->scsi.phase == PHASE_IDLE)
2514 	    acornscsi_kick(host);
2515 	local_irq_restore(flags);
2516     }
2517     return 0;
2518 }
2519 
2520 DEF_SCSI_QCMD(acornscsi_queuecmd)
2521 
2522 /*
2523  * Prototype: void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1, struct scsi_cmnd **SCpntp2, int result)
2524  * Purpose  : pass a result to *SCpntp1, and check if *SCpntp1 = *SCpntp2
2525  * Params   : SCpntp1 - pointer to command to return
2526  *	      SCpntp2 - pointer to command to check
2527  *	      result  - result to pass back to mid-level done function
2528  * Returns  : *SCpntp2 = NULL if *SCpntp1 is the same command structure as *SCpntp2.
2529  */
2530 static inline void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1,
2531 					  struct scsi_cmnd **SCpntp2,
2532 					  int result)
2533 {
2534 	struct scsi_cmnd *SCpnt = *SCpntp1;
2535 
2536     if (SCpnt) {
2537 	*SCpntp1 = NULL;
2538 
2539 	SCpnt->result = result;
2540 	SCpnt->scsi_done(SCpnt);
2541     }
2542 
2543     if (SCpnt == *SCpntp2)
2544 	*SCpntp2 = NULL;
2545 }
2546 
2547 enum res_abort { res_not_running, res_success, res_success_clear, res_snooze };
2548 
2549 /*
2550  * Prototype: enum res acornscsi_do_abort(struct scsi_cmnd *SCpnt)
2551  * Purpose  : abort a command on this host
2552  * Params   : SCpnt - command to abort
2553  * Returns  : our abort status
2554  */
2555 static enum res_abort acornscsi_do_abort(AS_Host *host, struct scsi_cmnd *SCpnt)
2556 {
2557 	enum res_abort res = res_not_running;
2558 
2559 	if (queue_remove_cmd(&host->queues.issue, SCpnt)) {
2560 		/*
2561 		 * The command was on the issue queue, and has not been
2562 		 * issued yet.  We can remove the command from the queue,
2563 		 * and acknowledge the abort.  Neither the devices nor the
2564 		 * interface know about the command.
2565 		 */
2566 //#if (DEBUG & DEBUG_ABORT)
2567 		printk("on issue queue ");
2568 //#endif
2569 		res = res_success;
2570 	} else if (queue_remove_cmd(&host->queues.disconnected, SCpnt)) {
2571 		/*
2572 		 * The command was on the disconnected queue.  Simply
2573 		 * acknowledge the abort condition, and when the target
2574 		 * reconnects, we will give it an ABORT message.  The
2575 		 * target should then disconnect, and we will clear
2576 		 * the busylun bit.
2577 		 */
2578 //#if (DEBUG & DEBUG_ABORT)
2579 		printk("on disconnected queue ");
2580 //#endif
2581 		res = res_success;
2582 	} else if (host->SCpnt == SCpnt) {
2583 		unsigned long flags;
2584 
2585 //#if (DEBUG & DEBUG_ABORT)
2586 		printk("executing ");
2587 //#endif
2588 
2589 		local_irq_save(flags);
2590 		switch (host->scsi.phase) {
2591 		/*
2592 		 * If the interface is idle, and the command is 'disconnectable',
2593 		 * then it is the same as on the disconnected queue.  We simply
2594 		 * remove all traces of the command.  When the target reconnects,
2595 		 * we will give it an ABORT message since the command could not
2596 		 * be found.  When the target finally disconnects, we will clear
2597 		 * the busylun bit.
2598 		 */
2599 		case PHASE_IDLE:
2600 			if (host->scsi.disconnectable) {
2601 				host->scsi.disconnectable = 0;
2602 				host->SCpnt = NULL;
2603 				res = res_success;
2604 			}
2605 			break;
2606 
2607 		/*
2608 		 * If the command has connected and done nothing further,
2609 		 * simply force a disconnect.  We also need to clear the
2610 		 * busylun bit.
2611 		 */
2612 		case PHASE_CONNECTED:
2613 			sbic_arm_write(host, SBIC_CMND, CMND_DISCONNECT);
2614 			host->SCpnt = NULL;
2615 			res = res_success_clear;
2616 			break;
2617 
2618 		default:
2619 			acornscsi_abortcmd(host, host->SCpnt->tag);
2620 			res = res_snooze;
2621 		}
2622 		local_irq_restore(flags);
2623 	} else if (host->origSCpnt == SCpnt) {
2624 		/*
2625 		 * The command will be executed next, but a command
2626 		 * is currently using the interface.  This is similar to
2627 		 * being on the issue queue, except the busylun bit has
2628 		 * been set.
2629 		 */
2630 		host->origSCpnt = NULL;
2631 //#if (DEBUG & DEBUG_ABORT)
2632 		printk("waiting for execution ");
2633 //#endif
2634 		res = res_success_clear;
2635 	} else
2636 		printk("unknown ");
2637 
2638 	return res;
2639 }
2640 
2641 /*
2642  * Prototype: int acornscsi_abort(struct scsi_cmnd *SCpnt)
2643  * Purpose  : abort a command on this host
2644  * Params   : SCpnt - command to abort
2645  * Returns  : one of SCSI_ABORT_ macros
2646  */
2647 int acornscsi_abort(struct scsi_cmnd *SCpnt)
2648 {
2649 	AS_Host *host = (AS_Host *) SCpnt->device->host->hostdata;
2650 	int result;
2651 
2652 	host->stats.aborts += 1;
2653 
2654 #if (DEBUG & DEBUG_ABORT)
2655 	{
2656 		int asr, ssr;
2657 		asr = sbic_arm_read(host, SBIC_ASR);
2658 		ssr = sbic_arm_read(host, SBIC_SSR);
2659 
2660 		printk(KERN_WARNING "acornscsi_abort: ");
2661 		print_sbic_status(asr, ssr, host->scsi.phase);
2662 		acornscsi_dumplog(host, SCpnt->device->id);
2663 	}
2664 #endif
2665 
2666 	printk("scsi%d: ", host->host->host_no);
2667 
2668 	switch (acornscsi_do_abort(host, SCpnt)) {
2669 	/*
2670 	 * We managed to find the command and cleared it out.
2671 	 * We do not expect the command to be executing on the
2672 	 * target, but we have set the busylun bit.
2673 	 */
2674 	case res_success_clear:
2675 //#if (DEBUG & DEBUG_ABORT)
2676 		printk("clear ");
2677 //#endif
2678 		clear_bit(SCpnt->device->id * 8 +
2679 			  (u8)(SCpnt->device->lun & 0x7), host->busyluns);
2680 
2681 	/*
2682 	 * We found the command, and cleared it out.  Either
2683 	 * the command is still known to be executing on the
2684 	 * target, or the busylun bit is not set.
2685 	 */
2686 	case res_success:
2687 //#if (DEBUG & DEBUG_ABORT)
2688 		printk("success\n");
2689 //#endif
2690 		result = SUCCESS;
2691 		break;
2692 
2693 	/*
2694 	 * We did find the command, but unfortunately we couldn't
2695 	 * unhook it from ourselves.  Wait some more, and if it
2696 	 * still doesn't complete, reset the interface.
2697 	 */
2698 	case res_snooze:
2699 //#if (DEBUG & DEBUG_ABORT)
2700 		printk("snooze\n");
2701 //#endif
2702 		result = FAILED;
2703 		break;
2704 
2705 	/*
2706 	 * The command could not be found (either because it completed,
2707 	 * or it got dropped.
2708 	 */
2709 	default:
2710 	case res_not_running:
2711 		acornscsi_dumplog(host, SCpnt->device->id);
2712 		result = FAILED;
2713 //#if (DEBUG & DEBUG_ABORT)
2714 		printk("not running\n");
2715 //#endif
2716 		break;
2717 	}
2718 
2719 	return result;
2720 }
2721 
2722 /*
2723  * Prototype: int acornscsi_reset(struct scsi_cmnd *SCpnt)
2724  * Purpose  : reset a command on this host/reset this host
2725  * Params   : SCpnt  - command causing reset
2726  * Returns  : one of SCSI_RESET_ macros
2727  */
2728 int acornscsi_bus_reset(struct scsi_cmnd *SCpnt)
2729 {
2730 	AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
2731 	struct scsi_cmnd *SCptr;
2732 
2733     host->stats.resets += 1;
2734 
2735 #if (DEBUG & DEBUG_RESET)
2736     {
2737 	int asr, ssr;
2738 
2739 	asr = sbic_arm_read(host, SBIC_ASR);
2740 	ssr = sbic_arm_read(host, SBIC_SSR);
2741 
2742 	printk(KERN_WARNING "acornscsi_reset: ");
2743 	print_sbic_status(asr, ssr, host->scsi.phase);
2744 	acornscsi_dumplog(host, SCpnt->device->id);
2745     }
2746 #endif
2747 
2748     acornscsi_dma_stop(host);
2749 
2750     /*
2751      * do hard reset.  This resets all devices on this host, and so we
2752      * must set the reset status on all commands.
2753      */
2754     acornscsi_resetcard(host);
2755 
2756     while ((SCptr = queue_remove(&host->queues.disconnected)) != NULL)
2757 	;
2758 
2759     return SUCCESS;
2760 }
2761 
2762 /*==============================================================================================
2763  * initialisation & miscellaneous support
2764  */
2765 
2766 /*
2767  * Function: char *acornscsi_info(struct Scsi_Host *host)
2768  * Purpose : return a string describing this interface
2769  * Params  : host - host to give information on
2770  * Returns : a constant string
2771  */
2772 const
2773 char *acornscsi_info(struct Scsi_Host *host)
2774 {
2775     static char string[100], *p;
2776 
2777     p = string;
2778 
2779     p += sprintf(string, "%s at port %08lX irq %d v%d.%d.%d"
2780 #ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2781     " SYNC"
2782 #endif
2783 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2784     " TAG"
2785 #endif
2786 #if (DEBUG & DEBUG_NO_WRITE)
2787     " NOWRITE (" __stringify(NO_WRITE) ")"
2788 #endif
2789 		, host->hostt->name, host->io_port, host->irq,
2790 		VER_MAJOR, VER_MINOR, VER_PATCH);
2791     return string;
2792 }
2793 
2794 static int acornscsi_show_info(struct seq_file *m, struct Scsi_Host *instance)
2795 {
2796     int devidx;
2797     struct scsi_device *scd;
2798     AS_Host *host;
2799 
2800     host  = (AS_Host *)instance->hostdata;
2801 
2802     seq_printf(m, "AcornSCSI driver v%d.%d.%d"
2803 #ifdef CONFIG_SCSI_ACORNSCSI_SYNC
2804     " SYNC"
2805 #endif
2806 #ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
2807     " TAG"
2808 #endif
2809 #if (DEBUG & DEBUG_NO_WRITE)
2810     " NOWRITE (" __stringify(NO_WRITE) ")"
2811 #endif
2812 		"\n\n", VER_MAJOR, VER_MINOR, VER_PATCH);
2813 
2814     seq_printf(m,	"SBIC: WD33C93A  Address: %p    IRQ : %d\n",
2815 			host->base + SBIC_REGIDX, host->scsi.irq);
2816 #ifdef USE_DMAC
2817     seq_printf(m,	"DMAC: uPC71071  Address: %p  IRQ : %d\n\n",
2818 			host->base + DMAC_OFFSET, host->scsi.irq);
2819 #endif
2820 
2821     seq_printf(m,	"Statistics:\n"
2822 			"Queued commands: %-10u    Issued commands: %-10u\n"
2823 			"Done commands  : %-10u    Reads          : %-10u\n"
2824 			"Writes         : %-10u    Others         : %-10u\n"
2825 			"Disconnects    : %-10u    Aborts         : %-10u\n"
2826 			"Resets         : %-10u\n\nLast phases:",
2827 			host->stats.queues,		host->stats.removes,
2828 			host->stats.fins,		host->stats.reads,
2829 			host->stats.writes,		host->stats.miscs,
2830 			host->stats.disconnects,	host->stats.aborts,
2831 			host->stats.resets);
2832 
2833     for (devidx = 0; devidx < 9; devidx ++) {
2834 	unsigned int statptr, prev;
2835 
2836 	seq_printf(m, "\n%c:", devidx == 8 ? 'H' : ('0' + devidx));
2837 	statptr = host->status_ptr[devidx] - 10;
2838 
2839 	if ((signed int)statptr < 0)
2840 	    statptr += STATUS_BUFFER_SIZE;
2841 
2842 	prev = host->status[devidx][statptr].when;
2843 
2844 	for (; statptr != host->status_ptr[devidx]; statptr = (statptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
2845 	    if (host->status[devidx][statptr].when) {
2846 		seq_printf(m, "%c%02X:%02X+%2ld",
2847 			host->status[devidx][statptr].irq ? '-' : ' ',
2848 			host->status[devidx][statptr].ph,
2849 			host->status[devidx][statptr].ssr,
2850 			(host->status[devidx][statptr].when - prev) < 100 ?
2851 				(host->status[devidx][statptr].when - prev) : 99);
2852 		prev = host->status[devidx][statptr].when;
2853 	    }
2854 	}
2855     }
2856 
2857     seq_printf(m, "\nAttached devices:\n");
2858 
2859     shost_for_each_device(scd, instance) {
2860 	seq_printf(m, "Device/Lun TaggedQ      Sync\n");
2861 	seq_printf(m, "     %d/%llu   ", scd->id, scd->lun);
2862 	if (scd->tagged_supported)
2863 		seq_printf(m, "%3sabled(%3d) ",
2864 			     scd->simple_tags ? "en" : "dis",
2865 			     scd->current_tag);
2866 	else
2867 		seq_printf(m, "unsupported  ");
2868 
2869 	if (host->device[scd->id].sync_xfer & 15)
2870 		seq_printf(m, "offset %d, %d ns\n",
2871 			     host->device[scd->id].sync_xfer & 15,
2872 			     acornscsi_getperiod(host->device[scd->id].sync_xfer));
2873 	else
2874 		seq_printf(m, "async\n");
2875 
2876     }
2877     return 0;
2878 }
2879 
2880 static struct scsi_host_template acornscsi_template = {
2881 	.module			= THIS_MODULE,
2882 	.show_info		= acornscsi_show_info,
2883 	.name			= "AcornSCSI",
2884 	.info			= acornscsi_info,
2885 	.queuecommand		= acornscsi_queuecmd,
2886 	.eh_abort_handler	= acornscsi_abort,
2887 	.eh_bus_reset_handler	= acornscsi_bus_reset,
2888 	.can_queue		= 16,
2889 	.this_id		= 7,
2890 	.sg_tablesize		= SG_ALL,
2891 	.cmd_per_lun		= 2,
2892 	.use_clustering		= DISABLE_CLUSTERING,
2893 	.proc_name		= "acornscsi",
2894 };
2895 
2896 static int acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
2897 {
2898 	struct Scsi_Host *host;
2899 	AS_Host *ashost;
2900 	int ret;
2901 
2902 	ret = ecard_request_resources(ec);
2903 	if (ret)
2904 		goto out;
2905 
2906 	host = scsi_host_alloc(&acornscsi_template, sizeof(AS_Host));
2907 	if (!host) {
2908 		ret = -ENOMEM;
2909 		goto out_release;
2910 	}
2911 
2912 	ashost = (AS_Host *)host->hostdata;
2913 
2914 	ashost->base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
2915 	ashost->fast = ecardm_iomap(ec, ECARD_RES_IOCFAST, 0, 0);
2916 	if (!ashost->base || !ashost->fast)
2917 		goto out_put;
2918 
2919 	host->irq = ec->irq;
2920 	ashost->host = host;
2921 	ashost->scsi.irq = host->irq;
2922 
2923 	ec->irqaddr	= ashost->fast + INT_REG;
2924 	ec->irqmask	= 0x0a;
2925 
2926 	ret = request_irq(host->irq, acornscsi_intr, 0, "acornscsi", ashost);
2927 	if (ret) {
2928 		printk(KERN_CRIT "scsi%d: IRQ%d not free: %d\n",
2929 			host->host_no, ashost->scsi.irq, ret);
2930 		goto out_put;
2931 	}
2932 
2933 	memset(&ashost->stats, 0, sizeof (ashost->stats));
2934 	queue_initialise(&ashost->queues.issue);
2935 	queue_initialise(&ashost->queues.disconnected);
2936 	msgqueue_initialise(&ashost->scsi.msgs);
2937 
2938 	acornscsi_resetcard(ashost);
2939 
2940 	ret = scsi_add_host(host, &ec->dev);
2941 	if (ret)
2942 		goto out_irq;
2943 
2944 	scsi_scan_host(host);
2945 	goto out;
2946 
2947  out_irq:
2948 	free_irq(host->irq, ashost);
2949 	msgqueue_free(&ashost->scsi.msgs);
2950 	queue_free(&ashost->queues.disconnected);
2951 	queue_free(&ashost->queues.issue);
2952  out_put:
2953 	ecardm_iounmap(ec, ashost->fast);
2954 	ecardm_iounmap(ec, ashost->base);
2955 	scsi_host_put(host);
2956  out_release:
2957 	ecard_release_resources(ec);
2958  out:
2959 	return ret;
2960 }
2961 
2962 static void acornscsi_remove(struct expansion_card *ec)
2963 {
2964 	struct Scsi_Host *host = ecard_get_drvdata(ec);
2965 	AS_Host *ashost = (AS_Host *)host->hostdata;
2966 
2967 	ecard_set_drvdata(ec, NULL);
2968 	scsi_remove_host(host);
2969 
2970 	/*
2971 	 * Put card into RESET state
2972 	 */
2973 	writeb(0x80, ashost->fast + PAGE_REG);
2974 
2975 	free_irq(host->irq, ashost);
2976 
2977 	msgqueue_free(&ashost->scsi.msgs);
2978 	queue_free(&ashost->queues.disconnected);
2979 	queue_free(&ashost->queues.issue);
2980 	ecardm_iounmap(ec, ashost->fast);
2981 	ecardm_iounmap(ec, ashost->base);
2982 	scsi_host_put(host);
2983 	ecard_release_resources(ec);
2984 }
2985 
2986 static const struct ecard_id acornscsi_cids[] = {
2987 	{ MANU_ACORN, PROD_ACORN_SCSI },
2988 	{ 0xffff, 0xffff },
2989 };
2990 
2991 static struct ecard_driver acornscsi_driver = {
2992 	.probe		= acornscsi_probe,
2993 	.remove		= acornscsi_remove,
2994 	.id_table	= acornscsi_cids,
2995 	.drv = {
2996 		.name		= "acornscsi",
2997 	},
2998 };
2999 
3000 static int __init acornscsi_init(void)
3001 {
3002 	return ecard_register_driver(&acornscsi_driver);
3003 }
3004 
3005 static void __exit acornscsi_exit(void)
3006 {
3007 	ecard_remove_driver(&acornscsi_driver);
3008 }
3009 
3010 module_init(acornscsi_init);
3011 module_exit(acornscsi_exit);
3012 
3013 MODULE_AUTHOR("Russell King");
3014 MODULE_DESCRIPTION("AcornSCSI driver");
3015 MODULE_LICENSE("GPL");
3016