xref: /linux/drivers/scsi/g_NCR5380.c (revision a9aaf1ff88a8cb99a1335c9eb76de637f0cf8c10)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic Generic NCR5380 driver
4  *
5  * Copyright 1993, Drew Eckhardt
6  * Visionary Computing
7  * (Unix and Linux consulting and custom programming)
8  * drew@colorado.edu
9  * +1 (303) 440-4894
10  *
11  * NCR53C400 extensions (c) 1994,1995,1996, Kevin Lentin
12  * K.Lentin@cs.monash.edu.au
13  *
14  * NCR53C400A extensions (c) 1996, Ingmar Baumgart
15  * ingmar@gonzo.schwaben.de
16  *
17  * DTC3181E extensions (c) 1997, Ronald van Cuijlenborg
18  * ronald.van.cuijlenborg@tip.nl or nutty@dds.nl
19  *
20  * Added ISAPNP support for DTC436 adapters,
21  * Thomas Sailer, sailer@ife.ee.ethz.ch
22  *
23  * See Documentation/scsi/g_NCR5380.rst for more info.
24  */
25 
26 #include <asm/io.h>
27 #include <linux/blkdev.h>
28 #include <linux/module.h>
29 #include <scsi/scsi_host.h>
30 #include <linux/init.h>
31 #include <linux/ioport.h>
32 #include <linux/isa.h>
33 #include <linux/pnp.h>
34 #include <linux/interrupt.h>
35 
36 /* Definitions for the core NCR5380 driver. */
37 
38 #define NCR5380_read(reg) \
39 	ioread8(hostdata->io + hostdata->offset + (reg))
40 #define NCR5380_write(reg, value) \
41 	iowrite8(value, hostdata->io + hostdata->offset + (reg))
42 
43 #define NCR5380_implementation_fields \
44 	int offset; \
45 	int c400_ctl_status; \
46 	int c400_blk_cnt; \
47 	int c400_host_buf; \
48 	int io_width; \
49 	int pdma_residual; \
50 	int board
51 
52 #define NCR5380_dma_xfer_len            generic_NCR5380_dma_xfer_len
53 #define NCR5380_dma_recv_setup          generic_NCR5380_precv
54 #define NCR5380_dma_send_setup          generic_NCR5380_psend
55 #define NCR5380_dma_residual            generic_NCR5380_dma_residual
56 
57 #define NCR5380_intr                    generic_NCR5380_intr
58 #define NCR5380_queue_command           generic_NCR5380_queue_command
59 #define NCR5380_abort                   generic_NCR5380_abort
60 #define NCR5380_host_reset              generic_NCR5380_host_reset
61 #define NCR5380_info                    generic_NCR5380_info
62 
63 #define NCR5380_io_delay(x)             udelay(x)
64 
65 #include "NCR5380.h"
66 
67 #define DRV_MODULE_NAME "g_NCR5380"
68 
69 #define NCR53C400_mem_base 0x3880
70 #define NCR53C400_host_buffer 0x3900
71 #define NCR53C400_region_size 0x3a00
72 
73 #define BOARD_NCR5380 0
74 #define BOARD_NCR53C400 1
75 #define BOARD_NCR53C400A 2
76 #define BOARD_DTC3181E 3
77 #define BOARD_HP_C2502 4
78 
79 #define IRQ_AUTO 254
80 
81 #define MAX_CARDS 8
82 #define DMA_MAX_SIZE 32768
83 
84 /* old-style parameters for compatibility */
85 static int ncr_irq = -1;
86 static int ncr_addr;
87 static int ncr_5380;
88 static int ncr_53c400;
89 static int ncr_53c400a;
90 static int dtc_3181e;
91 static int hp_c2502;
92 module_param_hw(ncr_irq, int, irq, 0);
93 module_param_hw(ncr_addr, int, ioport, 0);
94 module_param(ncr_5380, int, 0);
95 module_param(ncr_53c400, int, 0);
96 module_param(ncr_53c400a, int, 0);
97 module_param(dtc_3181e, int, 0);
98 module_param(hp_c2502, int, 0);
99 
100 static int irq[] = { -1, -1, -1, -1, -1, -1, -1, -1 };
101 module_param_hw_array(irq, int, irq, NULL, 0);
102 MODULE_PARM_DESC(irq, "IRQ number(s) (0=none, 254=auto [default])");
103 
104 static int base[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
105 module_param_hw_array(base, int, ioport, NULL, 0);
106 MODULE_PARM_DESC(base, "base address(es)");
107 
108 static int card[] = { -1, -1, -1, -1, -1, -1, -1, -1 };
109 module_param_array(card, int, NULL, 0);
110 MODULE_PARM_DESC(card, "card type (0=NCR5380, 1=NCR53C400, 2=NCR53C400A, 3=DTC3181E, 4=HP C2502)");
111 
112 MODULE_ALIAS("g_NCR5380_mmio");
113 MODULE_DESCRIPTION("Generic NCR5380/NCR53C400 SCSI driver");
114 MODULE_LICENSE("GPL");
115 
116 static void g_NCR5380_trigger_irq(struct Scsi_Host *instance)
117 {
118 	struct NCR5380_hostdata *hostdata = shost_priv(instance);
119 
120 	/*
121 	 * An interrupt is triggered whenever BSY = false, SEL = true
122 	 * and a bit set in the SELECT_ENABLE_REG is asserted on the
123 	 * SCSI bus.
124 	 *
125 	 * Note that the bus is only driven when the phase control signals
126 	 * (I/O, C/D, and MSG) match those in the TCR.
127 	 */
128 	NCR5380_write(TARGET_COMMAND_REG,
129 	              PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
130 	NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
131 	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
132 	NCR5380_write(INITIATOR_COMMAND_REG,
133 	              ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
134 
135 	msleep(1);
136 
137 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
138 	NCR5380_write(SELECT_ENABLE_REG, 0);
139 	NCR5380_write(TARGET_COMMAND_REG, 0);
140 }
141 
142 /**
143  * g_NCR5380_probe_irq - find the IRQ of a NCR5380 or equivalent
144  * @instance: SCSI host instance
145  *
146  * Autoprobe for the IRQ line used by the card by triggering an IRQ
147  * and then looking to see what interrupt actually turned up.
148  */
149 
150 static int g_NCR5380_probe_irq(struct Scsi_Host *instance)
151 {
152 	struct NCR5380_hostdata *hostdata = shost_priv(instance);
153 	int irq_mask, irq;
154 
155 	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
156 	irq_mask = probe_irq_on();
157 	g_NCR5380_trigger_irq(instance);
158 	irq = probe_irq_off(irq_mask);
159 	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
160 
161 	if (irq <= 0)
162 		return NO_IRQ;
163 	return irq;
164 }
165 
166 /*
167  * Configure I/O address of 53C400A or DTC436 by writing magic numbers
168  * to ports 0x779 and 0x379.
169  */
170 static void magic_configure(int idx, u8 irq, u8 magic[])
171 {
172 	u8 cfg = 0;
173 
174 	outb(magic[0], 0x779);
175 	outb(magic[1], 0x379);
176 	outb(magic[2], 0x379);
177 	outb(magic[3], 0x379);
178 	outb(magic[4], 0x379);
179 
180 	if (irq == 9)
181 		irq = 2;
182 
183 	if (idx >= 0 && idx <= 7)
184 		cfg = 0x80 | idx | (irq << 4);
185 	outb(cfg, 0x379);
186 }
187 
188 static irqreturn_t legacy_empty_irq_handler(int irq, void *dev_id)
189 {
190 	return IRQ_HANDLED;
191 }
192 
193 static int legacy_find_free_irq(int *irq_table)
194 {
195 	while (*irq_table != -1) {
196 		if (!request_irq(*irq_table, legacy_empty_irq_handler,
197 		                 IRQF_PROBE_SHARED, "Test IRQ",
198 		                 (void *)irq_table)) {
199 			free_irq(*irq_table, (void *) irq_table);
200 			return *irq_table;
201 		}
202 		irq_table++;
203 	}
204 	return -1;
205 }
206 
207 static unsigned int ncr_53c400a_ports[] = {
208 	0x280, 0x290, 0x300, 0x310, 0x330, 0x340, 0x348, 0x350, 0
209 };
210 static unsigned int dtc_3181e_ports[] = {
211 	0x220, 0x240, 0x280, 0x2a0, 0x2c0, 0x300, 0x320, 0x340, 0
212 };
213 static u8 ncr_53c400a_magic[] = {	/* 53C400A & DTC436 */
214 	0x59, 0xb9, 0xc5, 0xae, 0xa6
215 };
216 static u8 hp_c2502_magic[] = {	/* HP C2502 */
217 	0x0f, 0x22, 0xf0, 0x20, 0x80
218 };
219 static int hp_c2502_irqs[] = {
220 	9, 5, 7, 3, 4, -1
221 };
222 
223 static int generic_NCR5380_init_one(const struct scsi_host_template *tpnt,
224 			struct device *pdev, int base, int irq, int board)
225 {
226 	bool is_pmio = base <= 0xffff;
227 	int ret;
228 	int flags = 0;
229 	unsigned int *ports = NULL;
230 	u8 *magic = NULL;
231 	int i;
232 	int port_idx = -1;
233 	unsigned long region_size;
234 	struct Scsi_Host *instance;
235 	struct NCR5380_hostdata *hostdata;
236 	u8 __iomem *iomem;
237 
238 	switch (board) {
239 	case BOARD_NCR5380:
240 		flags = FLAG_NO_PSEUDO_DMA | FLAG_DMA_FIXUP;
241 		break;
242 	case BOARD_NCR53C400A:
243 		ports = ncr_53c400a_ports;
244 		magic = ncr_53c400a_magic;
245 		break;
246 	case BOARD_HP_C2502:
247 		ports = ncr_53c400a_ports;
248 		magic = hp_c2502_magic;
249 		break;
250 	case BOARD_DTC3181E:
251 		ports = dtc_3181e_ports;
252 		magic = ncr_53c400a_magic;
253 		break;
254 	}
255 
256 	if (is_pmio && ports && magic) {
257 		/* wakeup sequence for the NCR53C400A and DTC3181E */
258 
259 		/* Disable the adapter and look for a free io port */
260 		magic_configure(-1, 0, magic);
261 
262 		region_size = 16;
263 		if (base)
264 			for (i = 0; ports[i]; i++) {
265 				if (base == ports[i]) {	/* index found */
266 					if (!request_region(ports[i],
267 							    region_size,
268 							    "ncr53c80"))
269 						return -EBUSY;
270 					break;
271 				}
272 			}
273 		else
274 			for (i = 0; ports[i]; i++) {
275 				if (!request_region(ports[i], region_size,
276 						    "ncr53c80"))
277 					continue;
278 				if (inb(ports[i]) == 0xff)
279 					break;
280 				release_region(ports[i], region_size);
281 			}
282 		if (ports[i]) {
283 			/* At this point we have our region reserved */
284 			magic_configure(i, 0, magic); /* no IRQ yet */
285 			base = ports[i];
286 			outb(0xc0, base + 9);
287 			if (inb(base + 9) != 0x80) {
288 				ret = -ENODEV;
289 				goto out_release;
290 			}
291 			port_idx = i;
292 		} else
293 			return -EINVAL;
294 	} else if (is_pmio) {
295 		/* NCR5380 - no configuration, just grab */
296 		region_size = 8;
297 		if (!base || !request_region(base, region_size, "ncr5380"))
298 			return -EBUSY;
299 	} else {	/* MMIO */
300 		region_size = NCR53C400_region_size;
301 		if (!request_mem_region(base, region_size, "ncr5380"))
302 			return -EBUSY;
303 	}
304 
305 	if (is_pmio)
306 		iomem = ioport_map(base, region_size);
307 	else
308 		iomem = ioremap(base, region_size);
309 
310 	if (!iomem) {
311 		ret = -ENOMEM;
312 		goto out_release;
313 	}
314 
315 	instance = scsi_host_alloc(tpnt, sizeof(struct NCR5380_hostdata));
316 	if (instance == NULL) {
317 		ret = -ENOMEM;
318 		goto out_unmap;
319 	}
320 	hostdata = shost_priv(instance);
321 
322 	hostdata->board = board;
323 	hostdata->io = iomem;
324 	hostdata->region_size = region_size;
325 
326 	if (is_pmio) {
327 		hostdata->io_port = base;
328 		hostdata->io_width = 1; /* 8-bit PDMA by default */
329 		hostdata->offset = 0;
330 
331 		/*
332 		 * On NCR53C400 boards, NCR5380 registers are mapped 8 past
333 		 * the base address.
334 		 */
335 		switch (board) {
336 		case BOARD_NCR53C400:
337 			hostdata->io_port += 8;
338 			hostdata->c400_ctl_status = 0;
339 			hostdata->c400_blk_cnt = 1;
340 			hostdata->c400_host_buf = 4;
341 			break;
342 		case BOARD_DTC3181E:
343 			hostdata->io_width = 2;	/* 16-bit PDMA */
344 			fallthrough;
345 		case BOARD_NCR53C400A:
346 		case BOARD_HP_C2502:
347 			hostdata->c400_ctl_status = 9;
348 			hostdata->c400_blk_cnt = 10;
349 			hostdata->c400_host_buf = 8;
350 			break;
351 		}
352 	} else {
353 		hostdata->base = base;
354 		hostdata->offset = NCR53C400_mem_base;
355 		switch (board) {
356 		case BOARD_NCR53C400:
357 			hostdata->c400_ctl_status = 0x100;
358 			hostdata->c400_blk_cnt = 0x101;
359 			hostdata->c400_host_buf = 0x104;
360 			break;
361 		case BOARD_DTC3181E:
362 		case BOARD_NCR53C400A:
363 		case BOARD_HP_C2502:
364 			pr_err(DRV_MODULE_NAME ": unknown register offsets\n");
365 			ret = -EINVAL;
366 			goto out_unregister;
367 		}
368 	}
369 
370 	/* Check for vacant slot */
371 	NCR5380_write(MODE_REG, 0);
372 	if (NCR5380_read(MODE_REG) != 0) {
373 		ret = -ENODEV;
374 		goto out_unregister;
375 	}
376 
377 	ret = NCR5380_init(instance, flags | FLAG_LATE_DMA_SETUP);
378 	if (ret)
379 		goto out_unregister;
380 
381 	switch (board) {
382 	case BOARD_NCR53C400:
383 	case BOARD_DTC3181E:
384 	case BOARD_NCR53C400A:
385 	case BOARD_HP_C2502:
386 		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
387 	}
388 
389 	NCR5380_maybe_reset_bus(instance);
390 
391 	/* Compatibility with documented NCR5380 kernel parameters */
392 	if (irq == 255 || irq == 0)
393 		irq = NO_IRQ;
394 	else if (irq == -1)
395 		irq = IRQ_AUTO;
396 
397 	if (board == BOARD_HP_C2502) {
398 		int *irq_table = hp_c2502_irqs;
399 		int board_irq = -1;
400 
401 		switch (irq) {
402 		case NO_IRQ:
403 			board_irq = 0;
404 			break;
405 		case IRQ_AUTO:
406 			board_irq = legacy_find_free_irq(irq_table);
407 			break;
408 		default:
409 			while (*irq_table != -1)
410 				if (*irq_table++ == irq)
411 					board_irq = irq;
412 		}
413 
414 		if (board_irq <= 0) {
415 			board_irq = 0;
416 			irq = NO_IRQ;
417 		}
418 
419 		magic_configure(port_idx, board_irq, magic);
420 	}
421 
422 	if (irq == IRQ_AUTO) {
423 		instance->irq = g_NCR5380_probe_irq(instance);
424 		if (instance->irq == NO_IRQ)
425 			shost_printk(KERN_INFO, instance, "no irq detected\n");
426 	} else {
427 		instance->irq = irq;
428 		if (instance->irq == NO_IRQ)
429 			shost_printk(KERN_INFO, instance, "no irq provided\n");
430 	}
431 
432 	if (instance->irq != NO_IRQ) {
433 		if (request_irq(instance->irq, generic_NCR5380_intr,
434 				0, "NCR5380", instance)) {
435 			instance->irq = NO_IRQ;
436 			shost_printk(KERN_INFO, instance,
437 			             "irq %d denied\n", instance->irq);
438 		} else {
439 			shost_printk(KERN_INFO, instance,
440 			             "irq %d acquired\n", instance->irq);
441 		}
442 	}
443 
444 	ret = scsi_add_host(instance, pdev);
445 	if (ret)
446 		goto out_free_irq;
447 	scsi_scan_host(instance);
448 	dev_set_drvdata(pdev, instance);
449 	return 0;
450 
451 out_free_irq:
452 	if (instance->irq != NO_IRQ)
453 		free_irq(instance->irq, instance);
454 	NCR5380_exit(instance);
455 out_unregister:
456 	scsi_host_put(instance);
457 out_unmap:
458 	iounmap(iomem);
459 out_release:
460 	if (is_pmio)
461 		release_region(base, region_size);
462 	else
463 		release_mem_region(base, region_size);
464 	return ret;
465 }
466 
467 static void generic_NCR5380_release_resources(struct Scsi_Host *instance)
468 {
469 	struct NCR5380_hostdata *hostdata = shost_priv(instance);
470 	void __iomem *iomem = hostdata->io;
471 	unsigned long io_port = hostdata->io_port;
472 	unsigned long base = hostdata->base;
473 	unsigned long region_size = hostdata->region_size;
474 
475 	scsi_remove_host(instance);
476 	if (instance->irq != NO_IRQ)
477 		free_irq(instance->irq, instance);
478 	NCR5380_exit(instance);
479 	scsi_host_put(instance);
480 	iounmap(iomem);
481 	if (io_port)
482 		release_region(io_port, region_size);
483 	else
484 		release_mem_region(base, region_size);
485 }
486 
487 /* wait_for_53c80_access - wait for 53C80 registers to become accessible
488  * @hostdata: scsi host private data
489  *
490  * The registers within the 53C80 logic block are inaccessible until
491  * bit 7 in the 53C400 control status register gets asserted.
492  */
493 
494 static void wait_for_53c80_access(struct NCR5380_hostdata *hostdata)
495 {
496 	int count = 10000;
497 
498 	do {
499 		if (hostdata->board == BOARD_DTC3181E)
500 			udelay(4); /* DTC436 chip hangs without this */
501 		if (NCR5380_read(hostdata->c400_ctl_status) & CSR_53C80_REG)
502 			return;
503 	} while (--count > 0);
504 
505 	scmd_printk(KERN_ERR, hostdata->connected,
506 	            "53c80 registers not accessible, device will be reset\n");
507 	NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
508 	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
509 }
510 
511 /**
512  * generic_NCR5380_precv - pseudo DMA receive
513  * @hostdata: scsi host private data
514  * @dst: buffer to write into
515  * @len: transfer size
516  *
517  * Perform a pseudo DMA mode receive from a 53C400 or equivalent device.
518  */
519 
520 static inline int generic_NCR5380_precv(struct NCR5380_hostdata *hostdata,
521                                         unsigned char *dst, int len)
522 {
523 	int residual;
524 	int start = 0;
525 
526 	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE | CSR_TRANS_DIR);
527 	NCR5380_write(hostdata->c400_blk_cnt, len / 128);
528 
529 	do {
530 		if (start == len - 128) {
531 			/* Ignore End of DMA interrupt for the final buffer */
532 			if (NCR5380_poll_politely(hostdata, hostdata->c400_ctl_status,
533 			                          CSR_HOST_BUF_NOT_RDY, 0, 0) < 0)
534 				break;
535 		} else {
536 			if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
537 			                           CSR_HOST_BUF_NOT_RDY, 0,
538 			                           hostdata->c400_ctl_status,
539 			                           CSR_GATED_53C80_IRQ,
540 			                           CSR_GATED_53C80_IRQ, 0) < 0 ||
541 			    NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY)
542 				break;
543 		}
544 
545 		if (hostdata->io_port && hostdata->io_width == 2)
546 			insw(hostdata->io_port + hostdata->c400_host_buf,
547 			     dst + start, 64);
548 		else if (hostdata->io_port)
549 			insb(hostdata->io_port + hostdata->c400_host_buf,
550 			     dst + start, 128);
551 		else
552 			memcpy_fromio(dst + start,
553 				hostdata->io + NCR53C400_host_buffer, 128);
554 		start += 128;
555 	} while (start < len);
556 
557 	residual = len - start;
558 
559 	if (residual != 0) {
560 		/* 53c80 interrupt or transfer timeout. Reset 53c400 logic. */
561 		NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
562 		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
563 	}
564 	wait_for_53c80_access(hostdata);
565 
566 	if (residual == 0 && NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
567 	                                           BASR_END_DMA_TRANSFER,
568 	                                           BASR_END_DMA_TRANSFER,
569 						   0) < 0)
570 		scmd_printk(KERN_ERR, hostdata->connected, "%s: End of DMA timeout\n",
571 		            __func__);
572 
573 	hostdata->pdma_residual = residual;
574 
575 	return 0;
576 }
577 
578 /**
579  * generic_NCR5380_psend - pseudo DMA send
580  * @hostdata: scsi host private data
581  * @src: buffer to read from
582  * @len: transfer size
583  *
584  * Perform a pseudo DMA mode send to a 53C400 or equivalent device.
585  */
586 
587 static inline int generic_NCR5380_psend(struct NCR5380_hostdata *hostdata,
588                                         unsigned char *src, int len)
589 {
590 	int residual;
591 	int start = 0;
592 
593 	NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
594 	NCR5380_write(hostdata->c400_blk_cnt, len / 128);
595 
596 	do {
597 		if (NCR5380_poll_politely2(hostdata, hostdata->c400_ctl_status,
598 		                           CSR_HOST_BUF_NOT_RDY, 0,
599 		                           hostdata->c400_ctl_status,
600 		                           CSR_GATED_53C80_IRQ,
601 		                           CSR_GATED_53C80_IRQ, 0) < 0 ||
602 		    NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY) {
603 			/* Both 128 B buffers are in use */
604 			if (start >= 128)
605 				start -= 128;
606 			if (start >= 128)
607 				start -= 128;
608 			break;
609 		}
610 
611 		if (start >= len && NCR5380_read(hostdata->c400_blk_cnt) == 0)
612 			break;
613 
614 		if (NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ) {
615 			/* Host buffer is empty, other one is in use */
616 			if (start >= 128)
617 				start -= 128;
618 			break;
619 		}
620 
621 		if (start >= len)
622 			continue;
623 
624 		if (hostdata->io_port && hostdata->io_width == 2)
625 			outsw(hostdata->io_port + hostdata->c400_host_buf,
626 			      src + start, 64);
627 		else if (hostdata->io_port)
628 			outsb(hostdata->io_port + hostdata->c400_host_buf,
629 			      src + start, 128);
630 		else
631 			memcpy_toio(hostdata->io + NCR53C400_host_buffer,
632 			            src + start, 128);
633 		start += 128;
634 	} while (1);
635 
636 	residual = len - start;
637 
638 	if (residual != 0) {
639 		/* 53c80 interrupt or transfer timeout. Reset 53c400 logic. */
640 		NCR5380_write(hostdata->c400_ctl_status, CSR_RESET);
641 		NCR5380_write(hostdata->c400_ctl_status, CSR_BASE);
642 	}
643 	wait_for_53c80_access(hostdata);
644 
645 	if (residual == 0) {
646 		if (NCR5380_poll_politely(hostdata, TARGET_COMMAND_REG,
647 		                          TCR_LAST_BYTE_SENT, TCR_LAST_BYTE_SENT,
648 					  0) < 0)
649 			scmd_printk(KERN_ERR, hostdata->connected,
650 			            "%s: Last Byte Sent timeout\n", __func__);
651 
652 		if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
653 		                          BASR_END_DMA_TRANSFER, BASR_END_DMA_TRANSFER,
654 					  0) < 0)
655 			scmd_printk(KERN_ERR, hostdata->connected, "%s: End of DMA timeout\n",
656 			            __func__);
657 	}
658 
659 	hostdata->pdma_residual = residual;
660 
661 	return 0;
662 }
663 
664 static int generic_NCR5380_dma_xfer_len(struct NCR5380_hostdata *hostdata,
665                                         struct scsi_cmnd *cmd)
666 {
667 	int transfersize = NCR5380_to_ncmd(cmd)->this_residual;
668 
669 	if (hostdata->flags & FLAG_NO_PSEUDO_DMA)
670 		return 0;
671 
672 	/* 53C400 datasheet: non-modulo-128-byte transfers should use PIO */
673 	if (transfersize % 128)
674 		return 0;
675 
676 	/* Limit PDMA send to 512 B to avoid random corruption on DTC3181E */
677 	if (hostdata->board == BOARD_DTC3181E &&
678 	    cmd->sc_data_direction == DMA_TO_DEVICE)
679 		transfersize = min(transfersize, 512);
680 
681 	return min(transfersize, DMA_MAX_SIZE);
682 }
683 
684 static int generic_NCR5380_dma_residual(struct NCR5380_hostdata *hostdata)
685 {
686 	return hostdata->pdma_residual;
687 }
688 
689 /* Include the core driver code. */
690 
691 #include "NCR5380.c"
692 
693 static const struct scsi_host_template driver_template = {
694 	.module			= THIS_MODULE,
695 	.proc_name		= DRV_MODULE_NAME,
696 	.name			= "Generic NCR5380/NCR53C400 SCSI",
697 	.info			= generic_NCR5380_info,
698 	.queuecommand		= generic_NCR5380_queue_command,
699 	.eh_abort_handler	= generic_NCR5380_abort,
700 	.eh_host_reset_handler	= generic_NCR5380_host_reset,
701 	.can_queue		= 16,
702 	.this_id		= 7,
703 	.sg_tablesize		= SG_ALL,
704 	.cmd_per_lun		= 2,
705 	.dma_boundary		= PAGE_SIZE - 1,
706 	.cmd_size		= sizeof(struct NCR5380_cmd),
707 	.max_sectors		= 128,
708 };
709 
710 static int generic_NCR5380_isa_match(struct device *pdev, unsigned int ndev)
711 {
712 	int ret = generic_NCR5380_init_one(&driver_template, pdev, base[ndev],
713 	                                   irq[ndev], card[ndev]);
714 	if (ret) {
715 		if (base[ndev])
716 			printk(KERN_WARNING "Card not found at address 0x%03x\n",
717 			       base[ndev]);
718 		return 0;
719 	}
720 
721 	return 1;
722 }
723 
724 static void generic_NCR5380_isa_remove(struct device *pdev,
725 				       unsigned int ndev)
726 {
727 	generic_NCR5380_release_resources(dev_get_drvdata(pdev));
728 	dev_set_drvdata(pdev, NULL);
729 }
730 
731 static struct isa_driver generic_NCR5380_isa_driver = {
732 	.match		= generic_NCR5380_isa_match,
733 	.remove		= generic_NCR5380_isa_remove,
734 	.driver		= {
735 		.name	= DRV_MODULE_NAME
736 	},
737 };
738 
739 #ifdef CONFIG_PNP
740 static const struct pnp_device_id generic_NCR5380_pnp_ids[] = {
741 	{ .id = "DTC436e", .driver_data = BOARD_DTC3181E },
742 	{ .id = "" }
743 };
744 MODULE_DEVICE_TABLE(pnp, generic_NCR5380_pnp_ids);
745 
746 static int generic_NCR5380_pnp_probe(struct pnp_dev *pdev,
747                                      const struct pnp_device_id *id)
748 {
749 	int base, irq;
750 
751 	if (pnp_activate_dev(pdev) < 0)
752 		return -EBUSY;
753 
754 	base = pnp_port_start(pdev, 0);
755 	irq = pnp_irq(pdev, 0);
756 
757 	return generic_NCR5380_init_one(&driver_template, &pdev->dev, base, irq,
758 	                                id->driver_data);
759 }
760 
761 static void generic_NCR5380_pnp_remove(struct pnp_dev *pdev)
762 {
763 	generic_NCR5380_release_resources(pnp_get_drvdata(pdev));
764 	pnp_set_drvdata(pdev, NULL);
765 }
766 
767 static struct pnp_driver generic_NCR5380_pnp_driver = {
768 	.name		= DRV_MODULE_NAME,
769 	.id_table	= generic_NCR5380_pnp_ids,
770 	.probe		= generic_NCR5380_pnp_probe,
771 	.remove		= generic_NCR5380_pnp_remove,
772 };
773 #endif /* defined(CONFIG_PNP) */
774 
775 static int pnp_registered, isa_registered;
776 
777 static int __init generic_NCR5380_init(void)
778 {
779 	int ret = 0;
780 
781 	/* compatibility with old-style parameters */
782 	if (irq[0] == -1 && base[0] == 0 && card[0] == -1) {
783 		irq[0] = ncr_irq;
784 		base[0] = ncr_addr;
785 		if (ncr_5380)
786 			card[0] = BOARD_NCR5380;
787 		if (ncr_53c400)
788 			card[0] = BOARD_NCR53C400;
789 		if (ncr_53c400a)
790 			card[0] = BOARD_NCR53C400A;
791 		if (dtc_3181e)
792 			card[0] = BOARD_DTC3181E;
793 		if (hp_c2502)
794 			card[0] = BOARD_HP_C2502;
795 	}
796 
797 #ifdef CONFIG_PNP
798 	if (!pnp_register_driver(&generic_NCR5380_pnp_driver))
799 		pnp_registered = 1;
800 #endif
801 	ret = isa_register_driver(&generic_NCR5380_isa_driver, MAX_CARDS);
802 	if (!ret)
803 		isa_registered = 1;
804 
805 	return (pnp_registered || isa_registered) ? 0 : ret;
806 }
807 
808 static void __exit generic_NCR5380_exit(void)
809 {
810 #ifdef CONFIG_PNP
811 	if (pnp_registered)
812 		pnp_unregister_driver(&generic_NCR5380_pnp_driver);
813 #endif
814 	if (isa_registered)
815 		isa_unregister_driver(&generic_NCR5380_isa_driver);
816 }
817 
818 module_init(generic_NCR5380_init);
819 module_exit(generic_NCR5380_exit);
820