xref: /openbmc/linux/drivers/block/swim3.c (revision 78c99ba1)
1 /*
2  * Driver for the SWIM3 (Super Woz Integrated Machine 3)
3  * floppy controller found on Power Macintoshes.
4  *
5  * Copyright (C) 1996 Paul Mackerras.
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version
10  * 2 of the License, or (at your option) any later version.
11  */
12 
13 /*
14  * TODO:
15  * handle 2 drives
16  * handle GCR disks
17  */
18 
19 #include <linux/stddef.h>
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/timer.h>
23 #include <linux/delay.h>
24 #include <linux/fd.h>
25 #include <linux/ioctl.h>
26 #include <linux/blkdev.h>
27 #include <linux/interrupt.h>
28 #include <linux/module.h>
29 #include <linux/spinlock.h>
30 #include <asm/io.h>
31 #include <asm/dbdma.h>
32 #include <asm/prom.h>
33 #include <asm/uaccess.h>
34 #include <asm/mediabay.h>
35 #include <asm/machdep.h>
36 #include <asm/pmac_feature.h>
37 
38 static struct request_queue *swim3_queue;
39 static struct gendisk *disks[2];
40 static struct request *fd_req;
41 
42 #define MAX_FLOPPIES	2
43 
44 enum swim_state {
45 	idle,
46 	locating,
47 	seeking,
48 	settling,
49 	do_transfer,
50 	jogging,
51 	available,
52 	revalidating,
53 	ejecting
54 };
55 
56 #define REG(x)	unsigned char x; char x ## _pad[15];
57 
58 /*
59  * The names for these registers mostly represent speculation on my part.
60  * It will be interesting to see how close they are to the names Apple uses.
61  */
62 struct swim3 {
63 	REG(data);
64 	REG(timer);		/* counts down at 1MHz */
65 	REG(error);
66 	REG(mode);
67 	REG(select);		/* controls CA0, CA1, CA2 and LSTRB signals */
68 	REG(setup);
69 	REG(control);		/* writing bits clears them */
70 	REG(status);		/* writing bits sets them in control */
71 	REG(intr);
72 	REG(nseek);		/* # tracks to seek */
73 	REG(ctrack);		/* current track number */
74 	REG(csect);		/* current sector number */
75 	REG(gap3);		/* size of gap 3 in track format */
76 	REG(sector);		/* sector # to read or write */
77 	REG(nsect);		/* # sectors to read or write */
78 	REG(intr_enable);
79 };
80 
81 #define control_bic	control
82 #define control_bis	status
83 
84 /* Bits in select register */
85 #define CA_MASK		7
86 #define LSTRB		8
87 
88 /* Bits in control register */
89 #define DO_SEEK		0x80
90 #define FORMAT		0x40
91 #define SELECT		0x20
92 #define WRITE_SECTORS	0x10
93 #define DO_ACTION	0x08
94 #define DRIVE2_ENABLE	0x04
95 #define DRIVE_ENABLE	0x02
96 #define INTR_ENABLE	0x01
97 
98 /* Bits in status register */
99 #define FIFO_1BYTE	0x80
100 #define FIFO_2BYTE	0x40
101 #define ERROR		0x20
102 #define DATA		0x08
103 #define RDDATA		0x04
104 #define INTR_PENDING	0x02
105 #define MARK_BYTE	0x01
106 
107 /* Bits in intr and intr_enable registers */
108 #define ERROR_INTR	0x20
109 #define DATA_CHANGED	0x10
110 #define TRANSFER_DONE	0x08
111 #define SEEN_SECTOR	0x04
112 #define SEEK_DONE	0x02
113 #define TIMER_DONE	0x01
114 
115 /* Bits in error register */
116 #define ERR_DATA_CRC	0x80
117 #define ERR_ADDR_CRC	0x40
118 #define ERR_OVERRUN	0x04
119 #define ERR_UNDERRUN	0x01
120 
121 /* Bits in setup register */
122 #define S_SW_RESET	0x80
123 #define S_GCR_WRITE	0x40
124 #define S_IBM_DRIVE	0x20
125 #define S_TEST_MODE	0x10
126 #define S_FCLK_DIV2	0x08
127 #define S_GCR		0x04
128 #define S_COPY_PROT	0x02
129 #define S_INV_WDATA	0x01
130 
131 /* Select values for swim3_action */
132 #define SEEK_POSITIVE	0
133 #define SEEK_NEGATIVE	4
134 #define STEP		1
135 #define MOTOR_ON	2
136 #define MOTOR_OFF	6
137 #define INDEX		3
138 #define EJECT		7
139 #define SETMFM		9
140 #define SETGCR		13
141 
142 /* Select values for swim3_select and swim3_readbit */
143 #define STEP_DIR	0
144 #define STEPPING	1
145 #define MOTOR_ON	2
146 #define RELAX		3	/* also eject in progress */
147 #define READ_DATA_0	4
148 #define TWOMEG_DRIVE	5
149 #define SINGLE_SIDED	6	/* drive or diskette is 4MB type? */
150 #define DRIVE_PRESENT	7
151 #define DISK_IN		8
152 #define WRITE_PROT	9
153 #define TRACK_ZERO	10
154 #define TACHO		11
155 #define READ_DATA_1	12
156 #define MFM_MODE	13
157 #define SEEK_COMPLETE	14
158 #define ONEMEG_MEDIA	15
159 
160 /* Definitions of values used in writing and formatting */
161 #define DATA_ESCAPE	0x99
162 #define GCR_SYNC_EXC	0x3f
163 #define GCR_SYNC_CONV	0x80
164 #define GCR_FIRST_MARK	0xd5
165 #define GCR_SECOND_MARK	0xaa
166 #define GCR_ADDR_MARK	"\xd5\xaa\x00"
167 #define GCR_DATA_MARK	"\xd5\xaa\x0b"
168 #define GCR_SLIP_BYTE	"\x27\xaa"
169 #define GCR_SELF_SYNC	"\x3f\xbf\x1e\x34\x3c\x3f"
170 
171 #define DATA_99		"\x99\x99"
172 #define MFM_ADDR_MARK	"\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
173 #define MFM_INDEX_MARK	"\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
174 #define MFM_GAP_LEN	12
175 
176 struct floppy_state {
177 	enum swim_state	state;
178 	spinlock_t lock;
179 	struct swim3 __iomem *swim3;	/* hardware registers */
180 	struct dbdma_regs __iomem *dma;	/* DMA controller registers */
181 	int	swim3_intr;	/* interrupt number for SWIM3 */
182 	int	dma_intr;	/* interrupt number for DMA channel */
183 	int	cur_cyl;	/* cylinder head is on, or -1 */
184 	int	cur_sector;	/* last sector we saw go past */
185 	int	req_cyl;	/* the cylinder for the current r/w request */
186 	int	head;		/* head number ditto */
187 	int	req_sector;	/* sector number ditto */
188 	int	scount;		/* # sectors we're transferring at present */
189 	int	retries;
190 	int	settle_time;
191 	int	secpercyl;	/* disk geometry information */
192 	int	secpertrack;
193 	int	total_secs;
194 	int	write_prot;	/* 1 if write-protected, 0 if not, -1 dunno */
195 	struct dbdma_cmd *dma_cmd;
196 	int	ref_count;
197 	int	expect_cyl;
198 	struct timer_list timeout;
199 	int	timeout_pending;
200 	int	ejected;
201 	wait_queue_head_t wait;
202 	int	wanted;
203 	struct device_node*	media_bay; /* NULL when not in bay */
204 	char	dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
205 };
206 
207 static struct floppy_state floppy_states[MAX_FLOPPIES];
208 static int floppy_count = 0;
209 static DEFINE_SPINLOCK(swim3_lock);
210 
211 static unsigned short write_preamble[] = {
212 	0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e,	/* gap field */
213 	0, 0, 0, 0, 0, 0,			/* sync field */
214 	0x99a1, 0x99a1, 0x99a1, 0x99fb,		/* data address mark */
215 	0x990f					/* no escape for 512 bytes */
216 };
217 
218 static unsigned short write_postamble[] = {
219 	0x9904,					/* insert CRC */
220 	0x4e4e, 0x4e4e,
221 	0x9908,					/* stop writing */
222 	0, 0, 0, 0, 0, 0
223 };
224 
225 static void swim3_select(struct floppy_state *fs, int sel);
226 static void swim3_action(struct floppy_state *fs, int action);
227 static int swim3_readbit(struct floppy_state *fs, int bit);
228 static void do_fd_request(struct request_queue * q);
229 static void start_request(struct floppy_state *fs);
230 static void set_timeout(struct floppy_state *fs, int nticks,
231 			void (*proc)(unsigned long));
232 static void scan_track(struct floppy_state *fs);
233 static void seek_track(struct floppy_state *fs, int n);
234 static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
235 static void setup_transfer(struct floppy_state *fs);
236 static void act(struct floppy_state *fs);
237 static void scan_timeout(unsigned long data);
238 static void seek_timeout(unsigned long data);
239 static void settle_timeout(unsigned long data);
240 static void xfer_timeout(unsigned long data);
241 static irqreturn_t swim3_interrupt(int irq, void *dev_id);
242 /*static void fd_dma_interrupt(int irq, void *dev_id);*/
243 static int grab_drive(struct floppy_state *fs, enum swim_state state,
244 		      int interruptible);
245 static void release_drive(struct floppy_state *fs);
246 static int fd_eject(struct floppy_state *fs);
247 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
248 			unsigned int cmd, unsigned long param);
249 static int floppy_open(struct block_device *bdev, fmode_t mode);
250 static int floppy_release(struct gendisk *disk, fmode_t mode);
251 static int floppy_check_change(struct gendisk *disk);
252 static int floppy_revalidate(struct gendisk *disk);
253 
254 static bool swim3_end_request(int err, unsigned int nr_bytes)
255 {
256 	if (__blk_end_request(fd_req, err, nr_bytes))
257 		return true;
258 
259 	fd_req = NULL;
260 	return false;
261 }
262 
263 static bool swim3_end_request_cur(int err)
264 {
265 	return swim3_end_request(err, blk_rq_cur_bytes(fd_req));
266 }
267 
268 static void swim3_select(struct floppy_state *fs, int sel)
269 {
270 	struct swim3 __iomem *sw = fs->swim3;
271 
272 	out_8(&sw->select, RELAX);
273 	if (sel & 8)
274 		out_8(&sw->control_bis, SELECT);
275 	else
276 		out_8(&sw->control_bic, SELECT);
277 	out_8(&sw->select, sel & CA_MASK);
278 }
279 
280 static void swim3_action(struct floppy_state *fs, int action)
281 {
282 	struct swim3 __iomem *sw = fs->swim3;
283 
284 	swim3_select(fs, action);
285 	udelay(1);
286 	out_8(&sw->select, sw->select | LSTRB);
287 	udelay(2);
288 	out_8(&sw->select, sw->select & ~LSTRB);
289 	udelay(1);
290 }
291 
292 static int swim3_readbit(struct floppy_state *fs, int bit)
293 {
294 	struct swim3 __iomem *sw = fs->swim3;
295 	int stat;
296 
297 	swim3_select(fs, bit);
298 	udelay(1);
299 	stat = in_8(&sw->status);
300 	return (stat & DATA) == 0;
301 }
302 
303 static void do_fd_request(struct request_queue * q)
304 {
305 	int i;
306 	for(i=0;i<floppy_count;i++)
307 	{
308 #ifdef CONFIG_PMAC_MEDIABAY
309 		if (floppy_states[i].media_bay &&
310 			check_media_bay(floppy_states[i].media_bay, MB_FD))
311 			continue;
312 #endif /* CONFIG_PMAC_MEDIABAY */
313 		start_request(&floppy_states[i]);
314 	}
315 }
316 
317 static void start_request(struct floppy_state *fs)
318 {
319 	struct request *req;
320 	unsigned long x;
321 
322 	if (fs->state == idle && fs->wanted) {
323 		fs->state = available;
324 		wake_up(&fs->wait);
325 		return;
326 	}
327 	while (fs->state == idle) {
328 		if (!fd_req) {
329 			fd_req = blk_fetch_request(swim3_queue);
330 			if (!fd_req)
331 				break;
332 		}
333 		req = fd_req;
334 #if 0
335 		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%u buf=%p\n",
336 		       req->rq_disk->disk_name, req->cmd,
337 		       (long)blk_rq_pos(req), blk_rq_sectors(req), req->buffer);
338 		printk("           errors=%d current_nr_sectors=%u\n",
339 		       req->errors, blk_rq_cur_sectors(req));
340 #endif
341 
342 		if (blk_rq_pos(req) >= fs->total_secs) {
343 			swim3_end_request_cur(-EIO);
344 			continue;
345 		}
346 		if (fs->ejected) {
347 			swim3_end_request_cur(-EIO);
348 			continue;
349 		}
350 
351 		if (rq_data_dir(req) == WRITE) {
352 			if (fs->write_prot < 0)
353 				fs->write_prot = swim3_readbit(fs, WRITE_PROT);
354 			if (fs->write_prot) {
355 				swim3_end_request_cur(-EIO);
356 				continue;
357 			}
358 		}
359 
360 		/* Do not remove the cast. blk_rq_pos(req) is now a
361 		 * sector_t and can be 64 bits, but it will never go
362 		 * past 32 bits for this driver anyway, so we can
363 		 * safely cast it down and not have to do a 64/32
364 		 * division
365 		 */
366 		fs->req_cyl = ((long)blk_rq_pos(req)) / fs->secpercyl;
367 		x = ((long)blk_rq_pos(req)) % fs->secpercyl;
368 		fs->head = x / fs->secpertrack;
369 		fs->req_sector = x % fs->secpertrack + 1;
370 		fd_req = req;
371 		fs->state = do_transfer;
372 		fs->retries = 0;
373 
374 		act(fs);
375 	}
376 }
377 
378 static void set_timeout(struct floppy_state *fs, int nticks,
379 			void (*proc)(unsigned long))
380 {
381 	unsigned long flags;
382 
383 	spin_lock_irqsave(&fs->lock, flags);
384 	if (fs->timeout_pending)
385 		del_timer(&fs->timeout);
386 	fs->timeout.expires = jiffies + nticks;
387 	fs->timeout.function = proc;
388 	fs->timeout.data = (unsigned long) fs;
389 	add_timer(&fs->timeout);
390 	fs->timeout_pending = 1;
391 	spin_unlock_irqrestore(&fs->lock, flags);
392 }
393 
394 static inline void scan_track(struct floppy_state *fs)
395 {
396 	struct swim3 __iomem *sw = fs->swim3;
397 
398 	swim3_select(fs, READ_DATA_0);
399 	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
400 	in_8(&sw->error);
401 	out_8(&sw->intr_enable, SEEN_SECTOR);
402 	out_8(&sw->control_bis, DO_ACTION);
403 	/* enable intr when track found */
404 	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
405 }
406 
407 static inline void seek_track(struct floppy_state *fs, int n)
408 {
409 	struct swim3 __iomem *sw = fs->swim3;
410 
411 	if (n >= 0) {
412 		swim3_action(fs, SEEK_POSITIVE);
413 		sw->nseek = n;
414 	} else {
415 		swim3_action(fs, SEEK_NEGATIVE);
416 		sw->nseek = -n;
417 	}
418 	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
419 	swim3_select(fs, STEP);
420 	in_8(&sw->error);
421 	/* enable intr when seek finished */
422 	out_8(&sw->intr_enable, SEEK_DONE);
423 	out_8(&sw->control_bis, DO_SEEK);
424 	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
425 	fs->settle_time = 0;
426 }
427 
428 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
429 			    void *buf, int count)
430 {
431 	st_le16(&cp->req_count, count);
432 	st_le16(&cp->command, cmd);
433 	st_le32(&cp->phy_addr, virt_to_bus(buf));
434 	cp->xfer_status = 0;
435 }
436 
437 static inline void setup_transfer(struct floppy_state *fs)
438 {
439 	int n;
440 	struct swim3 __iomem *sw = fs->swim3;
441 	struct dbdma_cmd *cp = fs->dma_cmd;
442 	struct dbdma_regs __iomem *dr = fs->dma;
443 
444 	if (blk_rq_cur_sectors(fd_req) <= 0) {
445 		printk(KERN_ERR "swim3: transfer 0 sectors?\n");
446 		return;
447 	}
448 	if (rq_data_dir(fd_req) == WRITE)
449 		n = 1;
450 	else {
451 		n = fs->secpertrack - fs->req_sector + 1;
452 		if (n > blk_rq_cur_sectors(fd_req))
453 			n = blk_rq_cur_sectors(fd_req);
454 	}
455 	fs->scount = n;
456 	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
457 	out_8(&sw->sector, fs->req_sector);
458 	out_8(&sw->nsect, n);
459 	out_8(&sw->gap3, 0);
460 	out_le32(&dr->cmdptr, virt_to_bus(cp));
461 	if (rq_data_dir(fd_req) == WRITE) {
462 		/* Set up 3 dma commands: write preamble, data, postamble */
463 		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
464 		++cp;
465 		init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
466 		++cp;
467 		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
468 	} else {
469 		init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
470 	}
471 	++cp;
472 	out_le16(&cp->command, DBDMA_STOP);
473 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
474 	in_8(&sw->error);
475 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
476 	if (rq_data_dir(fd_req) == WRITE)
477 		out_8(&sw->control_bis, WRITE_SECTORS);
478 	in_8(&sw->intr);
479 	out_le32(&dr->control, (RUN << 16) | RUN);
480 	/* enable intr when transfer complete */
481 	out_8(&sw->intr_enable, TRANSFER_DONE);
482 	out_8(&sw->control_bis, DO_ACTION);
483 	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
484 }
485 
486 static void act(struct floppy_state *fs)
487 {
488 	for (;;) {
489 		switch (fs->state) {
490 		case idle:
491 			return;		/* XXX shouldn't get here */
492 
493 		case locating:
494 			if (swim3_readbit(fs, TRACK_ZERO)) {
495 				fs->cur_cyl = 0;
496 				if (fs->req_cyl == 0)
497 					fs->state = do_transfer;
498 				else
499 					fs->state = seeking;
500 				break;
501 			}
502 			scan_track(fs);
503 			return;
504 
505 		case seeking:
506 			if (fs->cur_cyl < 0) {
507 				fs->expect_cyl = -1;
508 				fs->state = locating;
509 				break;
510 			}
511 			if (fs->req_cyl == fs->cur_cyl) {
512 				printk("whoops, seeking 0\n");
513 				fs->state = do_transfer;
514 				break;
515 			}
516 			seek_track(fs, fs->req_cyl - fs->cur_cyl);
517 			return;
518 
519 		case settling:
520 			/* check for SEEK_COMPLETE after 30ms */
521 			fs->settle_time = (HZ + 32) / 33;
522 			set_timeout(fs, fs->settle_time, settle_timeout);
523 			return;
524 
525 		case do_transfer:
526 			if (fs->cur_cyl != fs->req_cyl) {
527 				if (fs->retries > 5) {
528 					swim3_end_request_cur(-EIO);
529 					fs->state = idle;
530 					return;
531 				}
532 				fs->state = seeking;
533 				break;
534 			}
535 			setup_transfer(fs);
536 			return;
537 
538 		case jogging:
539 			seek_track(fs, -5);
540 			return;
541 
542 		default:
543 			printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
544 			return;
545 		}
546 	}
547 }
548 
549 static void scan_timeout(unsigned long data)
550 {
551 	struct floppy_state *fs = (struct floppy_state *) data;
552 	struct swim3 __iomem *sw = fs->swim3;
553 
554 	fs->timeout_pending = 0;
555 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
556 	out_8(&sw->select, RELAX);
557 	out_8(&sw->intr_enable, 0);
558 	fs->cur_cyl = -1;
559 	if (fs->retries > 5) {
560 		swim3_end_request_cur(-EIO);
561 		fs->state = idle;
562 		start_request(fs);
563 	} else {
564 		fs->state = jogging;
565 		act(fs);
566 	}
567 }
568 
569 static void seek_timeout(unsigned long data)
570 {
571 	struct floppy_state *fs = (struct floppy_state *) data;
572 	struct swim3 __iomem *sw = fs->swim3;
573 
574 	fs->timeout_pending = 0;
575 	out_8(&sw->control_bic, DO_SEEK);
576 	out_8(&sw->select, RELAX);
577 	out_8(&sw->intr_enable, 0);
578 	printk(KERN_ERR "swim3: seek timeout\n");
579 	swim3_end_request_cur(-EIO);
580 	fs->state = idle;
581 	start_request(fs);
582 }
583 
584 static void settle_timeout(unsigned long data)
585 {
586 	struct floppy_state *fs = (struct floppy_state *) data;
587 	struct swim3 __iomem *sw = fs->swim3;
588 
589 	fs->timeout_pending = 0;
590 	if (swim3_readbit(fs, SEEK_COMPLETE)) {
591 		out_8(&sw->select, RELAX);
592 		fs->state = locating;
593 		act(fs);
594 		return;
595 	}
596 	out_8(&sw->select, RELAX);
597 	if (fs->settle_time < 2*HZ) {
598 		++fs->settle_time;
599 		set_timeout(fs, 1, settle_timeout);
600 		return;
601 	}
602 	printk(KERN_ERR "swim3: seek settle timeout\n");
603 	swim3_end_request_cur(-EIO);
604 	fs->state = idle;
605 	start_request(fs);
606 }
607 
608 static void xfer_timeout(unsigned long data)
609 {
610 	struct floppy_state *fs = (struct floppy_state *) data;
611 	struct swim3 __iomem *sw = fs->swim3;
612 	struct dbdma_regs __iomem *dr = fs->dma;
613 	int n;
614 
615 	fs->timeout_pending = 0;
616 	out_le32(&dr->control, RUN << 16);
617 	/* We must wait a bit for dbdma to stop */
618 	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
619 		udelay(1);
620 	out_8(&sw->intr_enable, 0);
621 	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
622 	out_8(&sw->select, RELAX);
623 	printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
624 	       (rq_data_dir(fd_req)==WRITE? "writ": "read"),
625 	       (long)blk_rq_pos(fd_req));
626 	swim3_end_request_cur(-EIO);
627 	fs->state = idle;
628 	start_request(fs);
629 }
630 
631 static irqreturn_t swim3_interrupt(int irq, void *dev_id)
632 {
633 	struct floppy_state *fs = (struct floppy_state *) dev_id;
634 	struct swim3 __iomem *sw = fs->swim3;
635 	int intr, err, n;
636 	int stat, resid;
637 	struct dbdma_regs __iomem *dr;
638 	struct dbdma_cmd *cp;
639 
640 	intr = in_8(&sw->intr);
641 	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
642 	if ((intr & ERROR_INTR) && fs->state != do_transfer)
643 		printk(KERN_ERR "swim3_interrupt, state=%d, dir=%x, intr=%x, err=%x\n",
644 		       fs->state, rq_data_dir(fd_req), intr, err);
645 	switch (fs->state) {
646 	case locating:
647 		if (intr & SEEN_SECTOR) {
648 			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
649 			out_8(&sw->select, RELAX);
650 			out_8(&sw->intr_enable, 0);
651 			del_timer(&fs->timeout);
652 			fs->timeout_pending = 0;
653 			if (sw->ctrack == 0xff) {
654 				printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
655 				fs->cur_cyl = -1;
656 				if (fs->retries > 5) {
657 					swim3_end_request_cur(-EIO);
658 					fs->state = idle;
659 					start_request(fs);
660 				} else {
661 					fs->state = jogging;
662 					act(fs);
663 				}
664 				break;
665 			}
666 			fs->cur_cyl = sw->ctrack;
667 			fs->cur_sector = sw->csect;
668 			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
669 				printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
670 				       fs->expect_cyl, fs->cur_cyl);
671 			fs->state = do_transfer;
672 			act(fs);
673 		}
674 		break;
675 	case seeking:
676 	case jogging:
677 		if (sw->nseek == 0) {
678 			out_8(&sw->control_bic, DO_SEEK);
679 			out_8(&sw->select, RELAX);
680 			out_8(&sw->intr_enable, 0);
681 			del_timer(&fs->timeout);
682 			fs->timeout_pending = 0;
683 			if (fs->state == seeking)
684 				++fs->retries;
685 			fs->state = settling;
686 			act(fs);
687 		}
688 		break;
689 	case settling:
690 		out_8(&sw->intr_enable, 0);
691 		del_timer(&fs->timeout);
692 		fs->timeout_pending = 0;
693 		act(fs);
694 		break;
695 	case do_transfer:
696 		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
697 			break;
698 		out_8(&sw->intr_enable, 0);
699 		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
700 		out_8(&sw->select, RELAX);
701 		del_timer(&fs->timeout);
702 		fs->timeout_pending = 0;
703 		dr = fs->dma;
704 		cp = fs->dma_cmd;
705 		if (rq_data_dir(fd_req) == WRITE)
706 			++cp;
707 		/*
708 		 * Check that the main data transfer has finished.
709 		 * On writing, the swim3 sometimes doesn't use
710 		 * up all the bytes of the postamble, so we can still
711 		 * see DMA active here.  That doesn't matter as long
712 		 * as all the sector data has been transferred.
713 		 */
714 		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
715 			/* wait a little while for DMA to complete */
716 			for (n = 0; n < 100; ++n) {
717 				if (cp->xfer_status != 0)
718 					break;
719 				udelay(1);
720 				barrier();
721 			}
722 		}
723 		/* turn off DMA */
724 		out_le32(&dr->control, (RUN | PAUSE) << 16);
725 		stat = ld_le16(&cp->xfer_status);
726 		resid = ld_le16(&cp->res_count);
727 		if (intr & ERROR_INTR) {
728 			n = fs->scount - 1 - resid / 512;
729 			if (n > 0) {
730 				blk_update_request(fd_req, 0, n << 9);
731 				fs->req_sector += n;
732 			}
733 			if (fs->retries < 5) {
734 				++fs->retries;
735 				act(fs);
736 			} else {
737 				printk("swim3: error %sing block %ld (err=%x)\n",
738 				       rq_data_dir(fd_req) == WRITE? "writ": "read",
739 				       (long)blk_rq_pos(fd_req), err);
740 				swim3_end_request_cur(-EIO);
741 				fs->state = idle;
742 			}
743 		} else {
744 			if ((stat & ACTIVE) == 0 || resid != 0) {
745 				/* musta been an error */
746 				printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
747 				printk(KERN_ERR "  state=%d, dir=%x, intr=%x, err=%x\n",
748 				       fs->state, rq_data_dir(fd_req), intr, err);
749 				swim3_end_request_cur(-EIO);
750 				fs->state = idle;
751 				start_request(fs);
752 				break;
753 			}
754 			if (swim3_end_request(0, fs->scount << 9)) {
755 				fs->req_sector += fs->scount;
756 				if (fs->req_sector > fs->secpertrack) {
757 					fs->req_sector -= fs->secpertrack;
758 					if (++fs->head > 1) {
759 						fs->head = 0;
760 						++fs->req_cyl;
761 					}
762 				}
763 				act(fs);
764 			} else
765 				fs->state = idle;
766 		}
767 		if (fs->state == idle)
768 			start_request(fs);
769 		break;
770 	default:
771 		printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
772 	}
773 	return IRQ_HANDLED;
774 }
775 
776 /*
777 static void fd_dma_interrupt(int irq, void *dev_id)
778 {
779 }
780 */
781 
782 static int grab_drive(struct floppy_state *fs, enum swim_state state,
783 		      int interruptible)
784 {
785 	unsigned long flags;
786 
787 	spin_lock_irqsave(&fs->lock, flags);
788 	if (fs->state != idle) {
789 		++fs->wanted;
790 		while (fs->state != available) {
791 			if (interruptible && signal_pending(current)) {
792 				--fs->wanted;
793 				spin_unlock_irqrestore(&fs->lock, flags);
794 				return -EINTR;
795 			}
796 			interruptible_sleep_on(&fs->wait);
797 		}
798 		--fs->wanted;
799 	}
800 	fs->state = state;
801 	spin_unlock_irqrestore(&fs->lock, flags);
802 	return 0;
803 }
804 
805 static void release_drive(struct floppy_state *fs)
806 {
807 	unsigned long flags;
808 
809 	spin_lock_irqsave(&fs->lock, flags);
810 	fs->state = idle;
811 	start_request(fs);
812 	spin_unlock_irqrestore(&fs->lock, flags);
813 }
814 
815 static int fd_eject(struct floppy_state *fs)
816 {
817 	int err, n;
818 
819 	err = grab_drive(fs, ejecting, 1);
820 	if (err)
821 		return err;
822 	swim3_action(fs, EJECT);
823 	for (n = 20; n > 0; --n) {
824 		if (signal_pending(current)) {
825 			err = -EINTR;
826 			break;
827 		}
828 		swim3_select(fs, RELAX);
829 		schedule_timeout_interruptible(1);
830 		if (swim3_readbit(fs, DISK_IN) == 0)
831 			break;
832 	}
833 	swim3_select(fs, RELAX);
834 	udelay(150);
835 	fs->ejected = 1;
836 	release_drive(fs);
837 	return err;
838 }
839 
840 static struct floppy_struct floppy_type =
841 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
842 
843 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
844 			unsigned int cmd, unsigned long param)
845 {
846 	struct floppy_state *fs = bdev->bd_disk->private_data;
847 	int err;
848 
849 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
850 		return -EPERM;
851 
852 #ifdef CONFIG_PMAC_MEDIABAY
853 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
854 		return -ENXIO;
855 #endif
856 
857 	switch (cmd) {
858 	case FDEJECT:
859 		if (fs->ref_count != 1)
860 			return -EBUSY;
861 		err = fd_eject(fs);
862 		return err;
863 	case FDGETPRM:
864 	        if (copy_to_user((void __user *) param, &floppy_type,
865 				 sizeof(struct floppy_struct)))
866 			return -EFAULT;
867 		return 0;
868 	}
869 	return -ENOTTY;
870 }
871 
872 static int floppy_open(struct block_device *bdev, fmode_t mode)
873 {
874 	struct floppy_state *fs = bdev->bd_disk->private_data;
875 	struct swim3 __iomem *sw = fs->swim3;
876 	int n, err = 0;
877 
878 	if (fs->ref_count == 0) {
879 #ifdef CONFIG_PMAC_MEDIABAY
880 		if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
881 			return -ENXIO;
882 #endif
883 		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
884 		out_8(&sw->control_bic, 0xff);
885 		out_8(&sw->mode, 0x95);
886 		udelay(10);
887 		out_8(&sw->intr_enable, 0);
888 		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
889 		swim3_action(fs, MOTOR_ON);
890 		fs->write_prot = -1;
891 		fs->cur_cyl = -1;
892 		for (n = 0; n < 2 * HZ; ++n) {
893 			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
894 				break;
895 			if (signal_pending(current)) {
896 				err = -EINTR;
897 				break;
898 			}
899 			swim3_select(fs, RELAX);
900 			schedule_timeout_interruptible(1);
901 		}
902 		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
903 				 || swim3_readbit(fs, DISK_IN) == 0))
904 			err = -ENXIO;
905 		swim3_action(fs, SETMFM);
906 		swim3_select(fs, RELAX);
907 
908 	} else if (fs->ref_count == -1 || mode & FMODE_EXCL)
909 		return -EBUSY;
910 
911 	if (err == 0 && (mode & FMODE_NDELAY) == 0
912 	    && (mode & (FMODE_READ|FMODE_WRITE))) {
913 		check_disk_change(bdev);
914 		if (fs->ejected)
915 			err = -ENXIO;
916 	}
917 
918 	if (err == 0 && (mode & FMODE_WRITE)) {
919 		if (fs->write_prot < 0)
920 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
921 		if (fs->write_prot)
922 			err = -EROFS;
923 	}
924 
925 	if (err) {
926 		if (fs->ref_count == 0) {
927 			swim3_action(fs, MOTOR_OFF);
928 			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
929 			swim3_select(fs, RELAX);
930 		}
931 		return err;
932 	}
933 
934 	if (mode & FMODE_EXCL)
935 		fs->ref_count = -1;
936 	else
937 		++fs->ref_count;
938 
939 	return 0;
940 }
941 
942 static int floppy_release(struct gendisk *disk, fmode_t mode)
943 {
944 	struct floppy_state *fs = disk->private_data;
945 	struct swim3 __iomem *sw = fs->swim3;
946 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
947 		swim3_action(fs, MOTOR_OFF);
948 		out_8(&sw->control_bic, 0xff);
949 		swim3_select(fs, RELAX);
950 	}
951 	return 0;
952 }
953 
954 static int floppy_check_change(struct gendisk *disk)
955 {
956 	struct floppy_state *fs = disk->private_data;
957 	return fs->ejected;
958 }
959 
960 static int floppy_revalidate(struct gendisk *disk)
961 {
962 	struct floppy_state *fs = disk->private_data;
963 	struct swim3 __iomem *sw;
964 	int ret, n;
965 
966 #ifdef CONFIG_PMAC_MEDIABAY
967 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
968 		return -ENXIO;
969 #endif
970 
971 	sw = fs->swim3;
972 	grab_drive(fs, revalidating, 0);
973 	out_8(&sw->intr_enable, 0);
974 	out_8(&sw->control_bis, DRIVE_ENABLE);
975 	swim3_action(fs, MOTOR_ON);	/* necessary? */
976 	fs->write_prot = -1;
977 	fs->cur_cyl = -1;
978 	mdelay(1);
979 	for (n = HZ; n > 0; --n) {
980 		if (swim3_readbit(fs, SEEK_COMPLETE))
981 			break;
982 		if (signal_pending(current))
983 			break;
984 		swim3_select(fs, RELAX);
985 		schedule_timeout_interruptible(1);
986 	}
987 	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
988 		|| swim3_readbit(fs, DISK_IN) == 0;
989 	if (ret)
990 		swim3_action(fs, MOTOR_OFF);
991 	else {
992 		fs->ejected = 0;
993 		swim3_action(fs, SETMFM);
994 	}
995 	swim3_select(fs, RELAX);
996 
997 	release_drive(fs);
998 	return ret;
999 }
1000 
1001 static struct block_device_operations floppy_fops = {
1002 	.open		= floppy_open,
1003 	.release	= floppy_release,
1004 	.locked_ioctl	= floppy_ioctl,
1005 	.media_changed	= floppy_check_change,
1006 	.revalidate_disk= floppy_revalidate,
1007 };
1008 
1009 static int swim3_add_device(struct macio_dev *mdev, int index)
1010 {
1011 	struct device_node *swim = mdev->ofdev.node;
1012 	struct device_node *mediabay;
1013 	struct floppy_state *fs = &floppy_states[index];
1014 	int rc = -EBUSY;
1015 
1016 	/* Check & Request resources */
1017 	if (macio_resource_count(mdev) < 2) {
1018 		printk(KERN_WARNING "ifd%d: no address for %s\n",
1019 		       index, swim->full_name);
1020 		return -ENXIO;
1021 	}
1022 	if (macio_irq_count(mdev) < 2) {
1023 		printk(KERN_WARNING "fd%d: no intrs for device %s\n",
1024 			index, swim->full_name);
1025 	}
1026 	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1027 		printk(KERN_ERR "fd%d: can't request mmio resource for %s\n",
1028 		       index, swim->full_name);
1029 		return -EBUSY;
1030 	}
1031 	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1032 		printk(KERN_ERR "fd%d: can't request dma resource for %s\n",
1033 		       index, swim->full_name);
1034 		macio_release_resource(mdev, 0);
1035 		return -EBUSY;
1036 	}
1037 	dev_set_drvdata(&mdev->ofdev.dev, fs);
1038 
1039 	mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ?
1040 		swim->parent : NULL;
1041 	if (mediabay == NULL)
1042 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1043 
1044 	memset(fs, 0, sizeof(*fs));
1045 	spin_lock_init(&fs->lock);
1046 	fs->state = idle;
1047 	fs->swim3 = (struct swim3 __iomem *)
1048 		ioremap(macio_resource_start(mdev, 0), 0x200);
1049 	if (fs->swim3 == NULL) {
1050 		printk("fd%d: couldn't map registers for %s\n",
1051 		       index, swim->full_name);
1052 		rc = -ENOMEM;
1053 		goto out_release;
1054 	}
1055 	fs->dma = (struct dbdma_regs __iomem *)
1056 		ioremap(macio_resource_start(mdev, 1), 0x200);
1057 	if (fs->dma == NULL) {
1058 		printk("fd%d: couldn't map DMA for %s\n",
1059 		       index, swim->full_name);
1060 		iounmap(fs->swim3);
1061 		rc = -ENOMEM;
1062 		goto out_release;
1063 	}
1064 	fs->swim3_intr = macio_irq(mdev, 0);
1065 	fs->dma_intr = macio_irq(mdev, 1);;
1066 	fs->cur_cyl = -1;
1067 	fs->cur_sector = -1;
1068 	fs->secpercyl = 36;
1069 	fs->secpertrack = 18;
1070 	fs->total_secs = 2880;
1071 	fs->media_bay = mediabay;
1072 	init_waitqueue_head(&fs->wait);
1073 
1074 	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1075 	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1076 	st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1077 
1078 	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1079 		printk(KERN_ERR "fd%d: couldn't request irq %d for %s\n",
1080 		       index, fs->swim3_intr, swim->full_name);
1081 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1082 		goto out_unmap;
1083 		return -EBUSY;
1084 	}
1085 /*
1086 	if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1087 		printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1088 		       fs->dma_intr);
1089 		return -EBUSY;
1090 	}
1091 */
1092 
1093 	init_timer(&fs->timeout);
1094 
1095 	printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1096 		mediabay ? "in media bay" : "");
1097 
1098 	return 0;
1099 
1100  out_unmap:
1101 	iounmap(fs->dma);
1102 	iounmap(fs->swim3);
1103 
1104  out_release:
1105 	macio_release_resource(mdev, 0);
1106 	macio_release_resource(mdev, 1);
1107 
1108 	return rc;
1109 }
1110 
1111 static int __devinit swim3_attach(struct macio_dev *mdev, const struct of_device_id *match)
1112 {
1113 	int i, rc;
1114 	struct gendisk *disk;
1115 
1116 	/* Add the drive */
1117 	rc = swim3_add_device(mdev, floppy_count);
1118 	if (rc)
1119 		return rc;
1120 
1121 	/* Now create the queue if not there yet */
1122 	if (swim3_queue == NULL) {
1123 		/* If we failed, there isn't much we can do as the driver is still
1124 		 * too dumb to remove the device, just bail out
1125 		 */
1126 		if (register_blkdev(FLOPPY_MAJOR, "fd"))
1127 			return 0;
1128 		swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1129 		if (swim3_queue == NULL) {
1130 			unregister_blkdev(FLOPPY_MAJOR, "fd");
1131 			return 0;
1132 		}
1133 	}
1134 
1135 	/* Now register that disk. Same comment about failure handling */
1136 	i = floppy_count++;
1137 	disk = disks[i] = alloc_disk(1);
1138 	if (disk == NULL)
1139 		return 0;
1140 
1141 	disk->major = FLOPPY_MAJOR;
1142 	disk->first_minor = i;
1143 	disk->fops = &floppy_fops;
1144 	disk->private_data = &floppy_states[i];
1145 	disk->queue = swim3_queue;
1146 	disk->flags |= GENHD_FL_REMOVABLE;
1147 	sprintf(disk->disk_name, "fd%d", i);
1148 	set_capacity(disk, 2880);
1149 	add_disk(disk);
1150 
1151 	return 0;
1152 }
1153 
1154 static struct of_device_id swim3_match[] =
1155 {
1156 	{
1157 	.name		= "swim3",
1158 	},
1159 	{
1160 	.compatible	= "ohare-swim3"
1161 	},
1162 	{
1163 	.compatible	= "swim3"
1164 	},
1165 };
1166 
1167 static struct macio_driver swim3_driver =
1168 {
1169 	.name 		= "swim3",
1170 	.match_table	= swim3_match,
1171 	.probe		= swim3_attach,
1172 #if 0
1173 	.suspend	= swim3_suspend,
1174 	.resume		= swim3_resume,
1175 #endif
1176 };
1177 
1178 
1179 int swim3_init(void)
1180 {
1181 	macio_register_driver(&swim3_driver);
1182 	return 0;
1183 }
1184 
1185 module_init(swim3_init)
1186 
1187 MODULE_LICENSE("GPL");
1188 MODULE_AUTHOR("Paul Mackerras");
1189 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1190