summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/g_NCR5380.c
blob: fc538181f8df16a2839835d442257a66875f6f82 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
/*
 * Generic Generic NCR5380 driver
 *
 * Copyright 1993, Drew Eckhardt
 * Visionary Computing
 * (Unix and Linux consulting and custom programming)
 * drew@colorado.edu
 * +1 (303) 440-4894
 *
 * NCR53C400 extensions (c) 1994,1995,1996, Kevin Lentin
 * K.Lentin@cs.monash.edu.au
 *
 * NCR53C400A extensions (c) 1996, Ingmar Baumgart
 * ingmar@gonzo.schwaben.de
 *
 * DTC3181E extensions (c) 1997, Ronald van Cuijlenborg
 * ronald.van.cuijlenborg@tip.nl or nutty@dds.nl
 *
 * Added ISAPNP support for DTC436 adapters,
 * Thomas Sailer, sailer@ife.ee.ethz.ch
 *
 * See Documentation/scsi/g_NCR5380.txt for more info.
 */

#include <asm/io.h>
#include <linux/blkdev.h>
#include <linux/module.h>
#include <scsi/scsi_host.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/isa.h>
#include <linux/pnp.h>
#include <linux/interrupt.h>

/* Definitions for the core NCR5380 driver. */

#define NCR5380_read(reg) \
	ioread8(hostdata->io + hostdata->offset + (reg))
#define NCR5380_write(reg, value) \
	iowrite8(value, hostdata->io + hostdata->offset + (reg))

#define NCR5380_implementation_fields \
	int offset; \
	int c400_ctl_status; \
	int c400_blk_cnt; \
	int c400_host_buf; \
	int io_width; \
	int pdma_residual; \
	int board

#define NCR5380_dma_xfer_len            generic_NCR5380_dma_xfer_len
#define NCR5380_dma_recv_setup          generic_NCR5380_precv
#define NCR5380_dma_send_setup          generic_NCR5380_psend
#define NCR5380_dma_residual            generic_NCR5380_dma_residual

#define NCR5380_intr                    generic_NCR5380_intr
#define NCR5380_queue_command           generic_NCR5380_queue_command
#define NCR5380_abort                   generic_NCR5380_abort
#define NCR5380_host_reset              generic_NCR5380_host_reset
#define NCR5380_info                    generic_NCR5380_info

#define NCR5380_io_delay(x)             udelay(x)

#include "NCR5380.h"

#define DRV_MODULE_NAME "g_NCR5380"

#define NCR53C400_mem_base 0x3880
#define NCR53C400_host_buffer 0x3900
#define NCR53C400_region_size 0x3a00

#define BOARD_NCR5380 0
#define BOARD_NCR53C400 1
#define BOARD_NCR53C400A 2
#define BOARD_DTC3181E 3
#define BOARD_HP_C2502 4

#define IRQ_AUTO 254

#define MAX_CARDS 8
#define DMA_MAX_SIZE 32768

/* old-style parameters for compatibility */
static int ncr_irq = -1;
static int ncr_addr;
static int ncr_5380;
static int ncr_53c400;
static int ncr_53c400a;
static int dtc_3181e;
static int hp_c2502;
module_param_hw(ncr_irq, int, irq, 0);
module_param_hw(ncr_addr, int, ioport, 0);
module_param(ncr_5380, int, 0);
module_param(ncr_53c400, int, 0);
module_param(ncr_53c400a, int, 0);
module_param(dtc_3181e, int, 0);
module_param(hp_c2502, int, 0);

static int irq[] = { -1, -1, -1, -1, -1, -1, -1, -1 };
module_param_hw_array(irq, int, irq, NULL, 0);
MODULE_PARM_DESC(irq, "IRQ number(s) (0=none, 254=auto [default])");

static int base[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
module_param_hw_array(base, int, ioport, NULL, 0);
MODULE_PARM_DESC(base, "base address(es)");

static int card[] = { -1, -1, -1, -1, -1, -1, -1, -1 };
module_param_array(card, int, NULL, 0);
MODULE_PARM_DESC(card, "card type (0=NCR5380, 1=NCR53C400, 2=NCR53C400A, 3=DTC3181E, 4=HP C2502)");

MODULE_ALIAS("g_NCR5380_mmio");
MODULE_LICENSE("GPL");

static void g_NCR5380_trigger_irq(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	/*
	 * An interrupt is triggered whenever BSY = false, SEL = true
	 * and a bit set in the SELECT_ENABLE_REG is asserted on the
	 * SCSI bus.
	 *
	 * Note that the bus is only driven when the phase control signals
	 * (I/O, C/D, and MSG) match those in the TCR.
	 */
	NCR5380_write(TARGET_COMMAND_REG,
	              PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
	NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
	NCR5380_write(INITIATOR_COMMAND_REG,
	              ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);

	msleep(1);

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	NCR5380_write(SELECT_ENABLE_REG, 0);
	NCR5380_write(TARGET_COMMAND_REG, 0);
}

/**
 * g_NCR5380_probe_irq - find the IRQ of a NCR5380 or equivalent
 * @instance: SCSI host instance
 *
 * Autoprobe for the IRQ line used by the card by triggering an IRQ
 * and then looking to see what interrupt actually turned up.
 */

static int g_NCR5380_probe_irq(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int irq_mask, irq;

	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	irq_mask = probe_irq_on();
	g_NCR5380_trigger_irq(instance);
	irq = probe_irq_off(irq_mask);
	NCR5380_read(RESET_PARITY_INTERRUPT_REG);

	if (irq <= 0)
		return NO_IRQ;
	return irq;
}

/*
 * Configure I/O address of 53C400A or DTC436 by writing magic numbers
 * to ports 0x779 and 0x379.
 */
static void magic_configure(int idx, u8 irq, u8 magic[])
{
	u8 cfg = 0;

	outb(magic[0], 0x779);
	outb(magic[1], 0x379);
	outb(magic[2], 0x379);
	outb(magic[3], 0x379);
	outb(magic[4], 0x379);

	if (irq == 9)
		irq = 2;

	if (idx >= 0 && idx <= 7)
		cfg = 0x80 | idx | (irq << 4);
	outb(cfg, 0x379);
}

static irqreturn_t legacy_empty_irq_handler(int irq, void *dev_id)
{
	return IRQ_HANDLED;
}

static int legacy_find_free_irq(int *irq_table)
{
	while (*irq_table != -1) {
		if (!request_irq(*irq_table, legacy_empty_irq_handler,
		                 IRQF_PROBE_SHARED, "Test IRQ",
		                 (void *)irq_table)) {
			free_irq(*irq_table, (void *) irq_table);
			return *irq_table;
		}
		irq_table++;
	}
	return -1;
}

static unsigned int ncr_53c400a_ports[] = {
	0x280, 0x290, 0x300, 0x310, 0x330, 0x340, 0x348, 0x350, 0
};
static unsigned int dtc_3181e_ports[] = {
	0x220, 0x240, 0x280, 0x2a0, 0x2c0, 0x300, 0x320, 0x340, 0
};
static u8 ncr_53c400a_magic[] = {	/* 53C400A & DTC436 */
	0x59, 0xb9, 0xc5, 0xae, 0xa6
};
static u8 hp_c2502_magic[] = {	/* HP C2502 */
	0x0f, 0x22, 0xf0, 0x20, 0x80
};
static int hp_c2502_irqs[] = {
	9, 5, 7, 3, 4, -1
};

static int generic_NCR5380_init_one(struct scsi_host_template *tpnt,
			struct device *pdev, int base, int irq, int board)
{
	bool is_pmio = base <= 0xffff;
	int ret;
	int flags = 0;
	unsigned int *ports = NULL;
	u8 *magic = NULL;
	int i;
	int port_idx = -1;
	unsigned long region_size;
	struct Scsi_Host *instance;
	struct NCR5380_hostdata *hostdata;
	u8 __iomem *iomem;

	switch (board) {
	case BOARD_NCR5380:
		flags = FLAG_NO_PSEUDO_DMA | FLAG_DMA_FIXUP;
		break;
	case BOARD_NCR53C400A:
		ports = ncr_53c400a_ports;
		magic = ncr_53c400a_magic;
		break;
	case BOARD_HP_C2502:
		ports = ncr_53c400a_ports;
		magic = hp_c2502_magic;
		break;
	case BOARD_DTC3181E:
		ports = dtc_3181e_ports;
		magic = ncr_53c400a_magic;
		break;
	}

	if (is_pmio && ports && magic) {
		/* wakeup sequence for the NCR53C400A and DTC3181E */

		/* Disable the adapter and look for a free io port */
		magic_configure(-1, 0, magic);

		region_size = 16;
		if (base)
			for (i = 0; ports[i]; i++) {
				if (base == ports[i]) {	/* index found */
					if (!request_region(ports[i],
							    region_size,
							    "ncr53c80"))
						return -EBUSY;
					break;
				}
			}
		else
			for (i = 0; ports[i]; i++) {
				if (!request_region(ports[i], region_size,
						    "ncr53c80"))
					continue;
				if (inb(ports[i]) == 0xff)
					break;
				release_region(ports[i], region_size);
			}
		if (ports[i]) {
			/* At this point we have our region reserved */
			magic_configure(i, 0, magic); /* no IRQ yet */
			base = ports[i];
			outb(0xc0, base + 9);
			if (inb(base + 9) != 0x80) {
				ret = -ENODEV;
				goto out_release;
			}
			port_idx = i;
		} else
			return -EINVAL;
	} else if (is_pmio) {
		/* NCR5380 - no configuration, just grab */
		region_size = 8;
		if (!base || !request_region(base, region_size, "ncr5380"))
			return -EBUSY;
	} else {	/* MMIO */
		region_size = NCR53C400_region_size;
		if (!request_mem_region(base, region_size, "ncr5380"))
			return -EBUSY;
	}

	if (is_pmio)
		iomem = ioport_map(base, region_size);
	else
		iomem = ioremap(base, region_size);

	if (!iomem) {
		ret = -ENOMEM;
		goto out_release;
	}

	instance = scsi_host_alloc(tpnt, sizeof(struct NCR5380_hostdata));
	if (instance == NULL) {
		ret = -ENOMEM;
		goto out_unmap;
	}
	hostdata = shost_priv(instance);

	hostdata->board = board;
	hostdata->io = iomem;
	hostdata->region_size = region_size;

	if (is_pmio) {
		hostdata->io_port = base;
		hostdata->io_width = 1; /* 8-bit PDMA by default */
		hostdata->offset = 0;

		/*
		 * On NCR53C400 boards, NCR5380 registers are mapped 8 past
		 * the base address.
		 */
		switch (board) {
		case BOARD_NCR53C400:
			hostdata->io_port += 8;
			hostdata->c400_ctl_status = 0;
			hostdata->c400_blk_cnt = 1;
			hostdata->c400_host_buf = 4;
			break;
		case BOARD_DTC3181E:
			hostdata->io_width = 2;	/* 16-bit PDMA */
			/* fall through */
		case BOARD_NCR53C400A:
		case BOARD_HP_C2502:
			hostdata->c400_ctl_status = 9;
			hostdata->c400_blk_cnt = 10;
			hostdata->c400_host_buf = 8;
			break;
		}
	} else {
		hostdata->base = base;
		hostdata->offset = NCR53C400_mem_base;
		switch (board) {
		case BOARD_NCR53C400:
			hostdata->c400_ctl_status = 0x100;
			hostdata->c400_blk_cnt = 0x101;
			hostdata->c400_host_buf = 0x104;
			break;
		case BOARD_DTC3181E:
		case BOARD_NCR53C400A:
		case BOARD_HP_C2502:
			pr_err(DRV_MODULE_NAME ": unknown register offsets\n");
			ret = -EINVAL;
			goto out_unregister;
		}
	}

	/* Check for vacant slot */
	NCR5380_write(MODE_REG, 0);
	if (NCR5380_read(MODE_REG) != 0) {
		ret = -ENODEV;
		goto out_unregister;
	}

	ret = NCR5380_init(instance, flags | FLAG_LATE_DMA_SETUP);
	if (ret)
		goto out_unregister;

	switch (board) {
	case BOARD_NCR53C400:
	case BOARD_DTC3181E:
	case BOARD_NCR53C400A:
	case BOARD_HP_C2502:
		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
	}

	NCR5380_maybe_reset_bus(instance);

	/* Compatibility with documented NCR5380 kernel parameters */
	if (irq == 255 || irq == 0)
		irq = NO_IRQ;
	else if (irq == -1)
		irq = IRQ_AUTO;

	if (board == BOARD_HP_C2502) {
		int *irq_table = hp_c2502_irqs;
		int board_irq = -1;

		switch (irq) {
		case NO_IRQ:
			board_irq = 0;
			break;
		case IRQ_AUTO:
			board_irq = legacy_find_free_irq(irq_table);
			break;
		default:
			while (*irq_table != -1)
				if (*irq_table++ == irq)
					board_irq = irq;
		}

		if (board_irq <= 0) {
			board_irq = 0;
			irq = NO_IRQ;
		}

		magic_configure(port_idx, board_irq, magic);
	}

	if (irq == IRQ_AUTO) {
		instance->irq = g_NCR5380_probe_irq(instance);
		if (instance->irq == NO_IRQ)
			shost_printk(KERN_INFO, instance, "no irq detected\n");
	} else {
		instance->irq = irq;
		if (instance->irq == NO_IRQ)
			shost_printk(KERN_INFO, instance, "no irq provided\n");
	}

	if (instance->irq != NO_IRQ) {
		if (request_irq(instance->irq, generic_NCR5380_intr,
				0, "NCR5380", instance)) {
			instance->irq = NO_IRQ;
			shost_printk(KERN_INFO, instance,
			             "irq %d denied\n", instance->irq);
		} else {
			shost_printk(KERN_INFO, instance,
			             "irq %d acquired\n", instance->irq);
		}
	}

	ret = scsi_add_host(instance, pdev);
	if (ret)
		goto out_free_irq;
	scsi_scan_host(instance);
	dev_set_drvdata(pdev, instance);
	return 0;

out_free_irq:
	if (instance->irq != NO_IRQ)
		free_irq(instance->irq, instance);
	NCR5380_exit(instance);
out_unregister:
	scsi_host_put(instance);
out_unmap:
	iounmap(iomem);
out_release:
	if (is_pmio)
		release_region(base, region_size);
	else
		release_mem_region(base, region_size);
	return ret;
}

static void generic_NCR5380_release_resources(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	void __iomem *iomem = hostdata->io;
	unsigned long io_port = hostdata->io_port;
	unsigned long base = hostdata->base;
	unsigned long region_size = hostdata->region_size;

	scsi_remove_host(instance);
	if (instance->irq != NO_IRQ)
		free_irq(instance->irq, instance);
	NCR5380_exit(instance);
	scsi_host_put(instance);
	iounmap(iomem);
	if (io_port)
		release_region(io_port, region_size);
	else
		release_mem_region(base, region_size);
}

/* wait_for_53c80_access - wait for 53C80 registers to become accessible
 * @hostdata: scsi host private data
 *
 * The registers within the 53C80 logic block are inaccessible until
 * bit 7 in the 53C400 control status register gets asserted.
 */

static void wait_for_53c80_access(struct NCR5380_hostdata *hostdata)
{
	int count = 10000;

	do {
		if (hostdata->board == BOARD_DTC3181E)
			udelay(4); /* DTC436 chip hangs without this */
		if (NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG)
			return;
	} while (--count > 0);

	scmd_printk(KERN_ERR, hostdata->connected,
	            "53c80 registers not accessible, device will be reset\n");
	NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
}

/**
 * generic_NCR5380_precv - pseudo DMA receive
 * @hostdata: scsi host private data
 * @dst: buffer to write into
 * @len: transfer size
 *
 * Perform a pseudo DMA mode receive from a 53C400 or equivalent device.
 */

static inline int generic_NCR5380_precv(struct NCR5380_hostdata *hostdata,
                                        unsigned char *dst, int len)
{
	int residual;
	int start = 0;

	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE | CSR_TRANS_DIR);
	NCR5380_write(hostdata->c400_blk_cnt, len / 128);

	do {
		if (start == len - 128) {
			/* Ignore End of DMA interrupt for the final buffer */
			if (NCR5380_poll_politely(hostdata, hostdata->c400_ctl_status,
			                          CSR_HOST_BUF_NOT_RDY, 0, HZ / 64) < 0)
				break;
		} else {
			if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
			                           CSR_HOST_BUF_NOT_RDY, 0,
			                           hostdata->c400_ctl_status,
			                           CSR_GATED_53C80_IRQ,
			                           CSR_GATED_53C80_IRQ, HZ / 64) < 0 ||
			    NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
				break;
		}

		if (hostdata->io_port && hostdata->io_width == 2)
			insw(hostdata->io_port + hostdata->c400_host_buf,
			     dst + start, 64);
		else if (hostdata->io_port)
			insb(hostdata->io_port + hostdata->c400_host_buf,
			     dst + start, 128);
		else
			memcpy_fromio(dst + start,
				hostdata->io + NCR53C400_host_buffer, 128);
		start += 128;
	} while (start < len);

	residual = len - start;

	if (residual != 0) {
		/* 53c80 interrupt or transfer timeout. Reset 53c400 logic. */
		NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
	}
	wait_for_53c80_access(hostdata);

	if (residual == 0 && NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
	                                           BASR_END_DMA_TRANSFER,
	                                           BASR_END_DMA_TRANSFER,
	                                           HZ / 64) < 0)
		scmd_printk(KERN_ERR, hostdata->connected, "%s: End of DMA timeout\n",
		            __func__);

	hostdata->pdma_residual = residual;

	return 0;
}

/**
 * generic_NCR5380_psend - pseudo DMA send
 * @hostdata: scsi host private data
 * @src: buffer to read from
 * @len: transfer size
 *
 * Perform a pseudo DMA mode send to a 53C400 or equivalent device.
 */

static inline int generic_NCR5380_psend(struct NCR5380_hostdata *hostdata,
                                        unsigned char *src, int len)
{
	int residual;
	int start = 0;

	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
	NCR5380_write(hostdata->c400_blk_cnt, len / 128);

	do {
		if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
		                           CSR_HOST_BUF_NOT_RDY, 0,
		                           hostdata->c400_ctl_status,
		                           CSR_GATED_53C80_IRQ,
		                           CSR_GATED_53C80_IRQ, HZ / 64) < 0 ||
		    NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY) {
			/* Both 128 B buffers are in use */
			if (start >= 128)
				start -= 128;
			if (start >= 128)
				start -= 128;
			break;
		}

		if (start >= len && NCR5380_read(hostdata->c400_blk_cnt) == 0)
			break;

		if (NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ) {
			/* Host buffer is empty, other one is in use */
			if (start >= 128)
				start -= 128;
			break;
		}

		if (start >= len)
			continue;

		if (hostdata->io_port && hostdata->io_width == 2)
			outsw(hostdata->io_port + hostdata->c400_host_buf,
			      src + start, 64);
		else if (hostdata->io_port)
			outsb(hostdata->io_port + hostdata->c400_host_buf,
			      src + start, 128);
		else
			memcpy_toio(hostdata->io + NCR53C400_host_buffer,
			            src + start, 128);
		start += 128;
	} while (1);

	residual = len - start;

	if (residual != 0) {
		/* 53c80 interrupt or transfer timeout. Reset 53c400 logic. */
		NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
	}
	wait_for_53c80_access(hostdata);

	if (residual == 0) {
		if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
		                          TCR_LAST_BYTE_SENT, TCR_LAST_BYTE_SENT,
		                          HZ / 64) < 0)
			scmd_printk(KERN_ERR, hostdata->connected,
			            "%s: Last Byte Sent timeout\n", __func__);

		if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
		                          BASR_END_DMA_TRANSFER, BASR_END_DMA_TRANSFER,
		                          HZ / 64) < 0)
			scmd_printk(KERN_ERR, hostdata->connected, "%s: End of DMA timeout\n",
			            __func__);
	}

	hostdata->pdma_residual = residual;

	return 0;
}

static int generic_NCR5380_dma_xfer_len(struct NCR5380_hostdata *hostdata,
                                        struct scsi_cmnd *cmd)
{
	int transfersize = cmd->SCp.this_residual;

	if (hostdata->flags & FLAG_NO_PSEUDO_DMA)
		return 0;

	/* 53C400 datasheet: non-modulo-128-byte transfers should use PIO */
	if (transfersize % 128)
		return 0;

	/* Limit PDMA send to 512 B to avoid random corruption on DTC3181E */
	if (hostdata->board == BOARD_DTC3181E &&
	    cmd->sc_data_direction == DMA_TO_DEVICE)
		transfersize = min(cmd->SCp.this_residual, 512);

	return min(transfersize, DMA_MAX_SIZE);
}

static int generic_NCR5380_dma_residual(struct NCR5380_hostdata *hostdata)
{
	return hostdata->pdma_residual;
}

/* Include the core driver code. */

#include "NCR5380.c"

static struct scsi_host_template driver_template = {
	.module			= THIS_MODULE,
	.proc_name		= DRV_MODULE_NAME,
	.name			= "Generic NCR5380/NCR53C400 SCSI",
	.info			= generic_NCR5380_info,
	.queuecommand		= generic_NCR5380_queue_command,
	.eh_abort_handler	= generic_NCR5380_abort,
	.eh_host_reset_handler	= generic_NCR5380_host_reset,
	.can_queue		= 16,
	.this_id		= 7,
	.sg_tablesize		= SG_ALL,
	.cmd_per_lun		= 2,
	.use_clustering		= DISABLE_CLUSTERING,
	.cmd_size		= NCR5380_CMD_SIZE,
	.max_sectors		= 128,
};

static int generic_NCR5380_isa_match(struct device *pdev, unsigned int ndev)
{
	int ret = generic_NCR5380_init_one(&driver_template, pdev, base[ndev],
	                                   irq[ndev], card[ndev]);
	if (ret) {
		if (base[ndev])
			printk(KERN_WARNING "Card not found at address 0x%03x\n",
			       base[ndev]);
		return 0;
	}

	return 1;
}

static int generic_NCR5380_isa_remove(struct device *pdev,
                                      unsigned int ndev)
{
	generic_NCR5380_release_resources(dev_get_drvdata(pdev));
	dev_set_drvdata(pdev, NULL);
	return 0;
}

static struct isa_driver generic_NCR5380_isa_driver = {
	.match		= generic_NCR5380_isa_match,
	.remove		= generic_NCR5380_isa_remove,
	.driver		= {
		.name	= DRV_MODULE_NAME
	},
};

#ifdef CONFIG_PNP
static const struct pnp_device_id generic_NCR5380_pnp_ids[] = {
	{ .id = "DTC436e", .driver_data = BOARD_DTC3181E },
	{ .id = "" }
};
MODULE_DEVICE_TABLE(pnp, generic_NCR5380_pnp_ids);

static int generic_NCR5380_pnp_probe(struct pnp_dev *pdev,
                                     const struct pnp_device_id *id)
{
	int base, irq;

	if (pnp_activate_dev(pdev) < 0)
		return -EBUSY;

	base = pnp_port_start(pdev, 0);
	irq = pnp_irq(pdev, 0);

	return generic_NCR5380_init_one(&driver_template, &pdev->dev, base, irq,
	                                id->driver_data);
}

static void generic_NCR5380_pnp_remove(struct pnp_dev *pdev)
{
	generic_NCR5380_release_resources(pnp_get_drvdata(pdev));
	pnp_set_drvdata(pdev, NULL);
}

static struct pnp_driver generic_NCR5380_pnp_driver = {
	.name		= DRV_MODULE_NAME,
	.id_table	= generic_NCR5380_pnp_ids,
	.probe		= generic_NCR5380_pnp_probe,
	.remove		= generic_NCR5380_pnp_remove,
};
#endif /* defined(CONFIG_PNP) */

static int pnp_registered, isa_registered;

static int __init generic_NCR5380_init(void)
{
	int ret = 0;

	/* compatibility with old-style parameters */
	if (irq[0] == -1 && base[0] == 0 && card[0] == -1) {
		irq[0] = ncr_irq;
		base[0] = ncr_addr;
		if (ncr_5380)
			card[0] = BOARD_NCR5380;
		if (ncr_53c400)
			card[0] = BOARD_NCR53C400;
		if (ncr_53c400a)
			card[0] = BOARD_NCR53C400A;
		if (dtc_3181e)
			card[0] = BOARD_DTC3181E;
		if (hp_c2502)
			card[0] = BOARD_HP_C2502;
	}

#ifdef CONFIG_PNP
	if (!pnp_register_driver(&generic_NCR5380_pnp_driver))
		pnp_registered = 1;
#endif
	ret = isa_register_driver(&generic_NCR5380_isa_driver, MAX_CARDS);
	if (!ret)
		isa_registered = 1;

	return (pnp_registered || isa_registered) ? 0 : ret;
}

static void __exit generic_NCR5380_exit(void)
{
#ifdef CONFIG_PNP
	if (pnp_registered)
		pnp_unregister_driver(&generic_NCR5380_pnp_driver);
#endif
	if (isa_registered)
		isa_unregister_driver(&generic_NCR5380_isa_driver);
}

module_init(generic_NCR5380_init);
module_exit(generic_NCR5380_exit);