xref: /openbmc/linux/drivers/block/swim3.c (revision c21b37f6)
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 inode *inode, struct file *filp,
248 			unsigned int cmd, unsigned long param);
249 static int floppy_open(struct inode *inode, struct file *filp);
250 static int floppy_release(struct inode *inode, struct file *filp);
251 static int floppy_check_change(struct gendisk *disk);
252 static int floppy_revalidate(struct gendisk *disk);
253 
254 #ifndef CONFIG_PMAC_MEDIABAY
255 #define check_media_bay(which, what)	1
256 #endif
257 
258 static void swim3_select(struct floppy_state *fs, int sel)
259 {
260 	struct swim3 __iomem *sw = fs->swim3;
261 
262 	out_8(&sw->select, RELAX);
263 	if (sel & 8)
264 		out_8(&sw->control_bis, SELECT);
265 	else
266 		out_8(&sw->control_bic, SELECT);
267 	out_8(&sw->select, sel & CA_MASK);
268 }
269 
270 static void swim3_action(struct floppy_state *fs, int action)
271 {
272 	struct swim3 __iomem *sw = fs->swim3;
273 
274 	swim3_select(fs, action);
275 	udelay(1);
276 	out_8(&sw->select, sw->select | LSTRB);
277 	udelay(2);
278 	out_8(&sw->select, sw->select & ~LSTRB);
279 	udelay(1);
280 }
281 
282 static int swim3_readbit(struct floppy_state *fs, int bit)
283 {
284 	struct swim3 __iomem *sw = fs->swim3;
285 	int stat;
286 
287 	swim3_select(fs, bit);
288 	udelay(1);
289 	stat = in_8(&sw->status);
290 	return (stat & DATA) == 0;
291 }
292 
293 static void do_fd_request(struct request_queue * q)
294 {
295 	int i;
296 	for(i=0;i<floppy_count;i++)
297 	{
298 #ifdef CONFIG_PMAC_MEDIABAY
299 		if (floppy_states[i].media_bay &&
300 			check_media_bay(floppy_states[i].media_bay, MB_FD))
301 			continue;
302 #endif /* CONFIG_PMAC_MEDIABAY */
303 		start_request(&floppy_states[i]);
304 	}
305 }
306 
307 static void start_request(struct floppy_state *fs)
308 {
309 	struct request *req;
310 	unsigned long x;
311 
312 	if (fs->state == idle && fs->wanted) {
313 		fs->state = available;
314 		wake_up(&fs->wait);
315 		return;
316 	}
317 	while (fs->state == idle && (req = elv_next_request(swim3_queue))) {
318 #if 0
319 		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
320 		       req->rq_disk->disk_name, req->cmd,
321 		       (long)req->sector, req->nr_sectors, req->buffer);
322 		printk("           errors=%d current_nr_sectors=%ld\n",
323 		       req->errors, req->current_nr_sectors);
324 #endif
325 
326 		if (req->sector < 0 || req->sector >= fs->total_secs) {
327 			end_request(req, 0);
328 			continue;
329 		}
330 		if (req->current_nr_sectors == 0) {
331 			end_request(req, 1);
332 			continue;
333 		}
334 		if (fs->ejected) {
335 			end_request(req, 0);
336 			continue;
337 		}
338 
339 		if (rq_data_dir(req) == WRITE) {
340 			if (fs->write_prot < 0)
341 				fs->write_prot = swim3_readbit(fs, WRITE_PROT);
342 			if (fs->write_prot) {
343 				end_request(req, 0);
344 				continue;
345 			}
346 		}
347 
348 		/* Do not remove the cast. req->sector is now a sector_t and
349 		 * can be 64 bits, but it will never go past 32 bits for this
350 		 * driver anyway, so we can safely cast it down and not have
351 		 * to do a 64/32 division
352 		 */
353 		fs->req_cyl = ((long)req->sector) / fs->secpercyl;
354 		x = ((long)req->sector) % fs->secpercyl;
355 		fs->head = x / fs->secpertrack;
356 		fs->req_sector = x % fs->secpertrack + 1;
357 		fd_req = req;
358 		fs->state = do_transfer;
359 		fs->retries = 0;
360 
361 		act(fs);
362 	}
363 }
364 
365 static void set_timeout(struct floppy_state *fs, int nticks,
366 			void (*proc)(unsigned long))
367 {
368 	unsigned long flags;
369 
370 	spin_lock_irqsave(&fs->lock, flags);
371 	if (fs->timeout_pending)
372 		del_timer(&fs->timeout);
373 	fs->timeout.expires = jiffies + nticks;
374 	fs->timeout.function = proc;
375 	fs->timeout.data = (unsigned long) fs;
376 	add_timer(&fs->timeout);
377 	fs->timeout_pending = 1;
378 	spin_unlock_irqrestore(&fs->lock, flags);
379 }
380 
381 static inline void scan_track(struct floppy_state *fs)
382 {
383 	struct swim3 __iomem *sw = fs->swim3;
384 
385 	swim3_select(fs, READ_DATA_0);
386 	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
387 	in_8(&sw->error);
388 	out_8(&sw->intr_enable, SEEN_SECTOR);
389 	out_8(&sw->control_bis, DO_ACTION);
390 	/* enable intr when track found */
391 	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
392 }
393 
394 static inline void seek_track(struct floppy_state *fs, int n)
395 {
396 	struct swim3 __iomem *sw = fs->swim3;
397 
398 	if (n >= 0) {
399 		swim3_action(fs, SEEK_POSITIVE);
400 		sw->nseek = n;
401 	} else {
402 		swim3_action(fs, SEEK_NEGATIVE);
403 		sw->nseek = -n;
404 	}
405 	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
406 	swim3_select(fs, STEP);
407 	in_8(&sw->error);
408 	/* enable intr when seek finished */
409 	out_8(&sw->intr_enable, SEEK_DONE);
410 	out_8(&sw->control_bis, DO_SEEK);
411 	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
412 	fs->settle_time = 0;
413 }
414 
415 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
416 			    void *buf, int count)
417 {
418 	st_le16(&cp->req_count, count);
419 	st_le16(&cp->command, cmd);
420 	st_le32(&cp->phy_addr, virt_to_bus(buf));
421 	cp->xfer_status = 0;
422 }
423 
424 static inline void setup_transfer(struct floppy_state *fs)
425 {
426 	int n;
427 	struct swim3 __iomem *sw = fs->swim3;
428 	struct dbdma_cmd *cp = fs->dma_cmd;
429 	struct dbdma_regs __iomem *dr = fs->dma;
430 
431 	if (fd_req->current_nr_sectors <= 0) {
432 		printk(KERN_ERR "swim3: transfer 0 sectors?\n");
433 		return;
434 	}
435 	if (rq_data_dir(fd_req) == WRITE)
436 		n = 1;
437 	else {
438 		n = fs->secpertrack - fs->req_sector + 1;
439 		if (n > fd_req->current_nr_sectors)
440 			n = fd_req->current_nr_sectors;
441 	}
442 	fs->scount = n;
443 	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
444 	out_8(&sw->sector, fs->req_sector);
445 	out_8(&sw->nsect, n);
446 	out_8(&sw->gap3, 0);
447 	out_le32(&dr->cmdptr, virt_to_bus(cp));
448 	if (rq_data_dir(fd_req) == WRITE) {
449 		/* Set up 3 dma commands: write preamble, data, postamble */
450 		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
451 		++cp;
452 		init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
453 		++cp;
454 		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
455 	} else {
456 		init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
457 	}
458 	++cp;
459 	out_le16(&cp->command, DBDMA_STOP);
460 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
461 	in_8(&sw->error);
462 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
463 	if (rq_data_dir(fd_req) == WRITE)
464 		out_8(&sw->control_bis, WRITE_SECTORS);
465 	in_8(&sw->intr);
466 	out_le32(&dr->control, (RUN << 16) | RUN);
467 	/* enable intr when transfer complete */
468 	out_8(&sw->intr_enable, TRANSFER_DONE);
469 	out_8(&sw->control_bis, DO_ACTION);
470 	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
471 }
472 
473 static void act(struct floppy_state *fs)
474 {
475 	for (;;) {
476 		switch (fs->state) {
477 		case idle:
478 			return;		/* XXX shouldn't get here */
479 
480 		case locating:
481 			if (swim3_readbit(fs, TRACK_ZERO)) {
482 				fs->cur_cyl = 0;
483 				if (fs->req_cyl == 0)
484 					fs->state = do_transfer;
485 				else
486 					fs->state = seeking;
487 				break;
488 			}
489 			scan_track(fs);
490 			return;
491 
492 		case seeking:
493 			if (fs->cur_cyl < 0) {
494 				fs->expect_cyl = -1;
495 				fs->state = locating;
496 				break;
497 			}
498 			if (fs->req_cyl == fs->cur_cyl) {
499 				printk("whoops, seeking 0\n");
500 				fs->state = do_transfer;
501 				break;
502 			}
503 			seek_track(fs, fs->req_cyl - fs->cur_cyl);
504 			return;
505 
506 		case settling:
507 			/* check for SEEK_COMPLETE after 30ms */
508 			fs->settle_time = (HZ + 32) / 33;
509 			set_timeout(fs, fs->settle_time, settle_timeout);
510 			return;
511 
512 		case do_transfer:
513 			if (fs->cur_cyl != fs->req_cyl) {
514 				if (fs->retries > 5) {
515 					end_request(fd_req, 0);
516 					fs->state = idle;
517 					return;
518 				}
519 				fs->state = seeking;
520 				break;
521 			}
522 			setup_transfer(fs);
523 			return;
524 
525 		case jogging:
526 			seek_track(fs, -5);
527 			return;
528 
529 		default:
530 			printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
531 			return;
532 		}
533 	}
534 }
535 
536 static void scan_timeout(unsigned long data)
537 {
538 	struct floppy_state *fs = (struct floppy_state *) data;
539 	struct swim3 __iomem *sw = fs->swim3;
540 
541 	fs->timeout_pending = 0;
542 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
543 	out_8(&sw->select, RELAX);
544 	out_8(&sw->intr_enable, 0);
545 	fs->cur_cyl = -1;
546 	if (fs->retries > 5) {
547 		end_request(fd_req, 0);
548 		fs->state = idle;
549 		start_request(fs);
550 	} else {
551 		fs->state = jogging;
552 		act(fs);
553 	}
554 }
555 
556 static void seek_timeout(unsigned long data)
557 {
558 	struct floppy_state *fs = (struct floppy_state *) data;
559 	struct swim3 __iomem *sw = fs->swim3;
560 
561 	fs->timeout_pending = 0;
562 	out_8(&sw->control_bic, DO_SEEK);
563 	out_8(&sw->select, RELAX);
564 	out_8(&sw->intr_enable, 0);
565 	printk(KERN_ERR "swim3: seek timeout\n");
566 	end_request(fd_req, 0);
567 	fs->state = idle;
568 	start_request(fs);
569 }
570 
571 static void settle_timeout(unsigned long data)
572 {
573 	struct floppy_state *fs = (struct floppy_state *) data;
574 	struct swim3 __iomem *sw = fs->swim3;
575 
576 	fs->timeout_pending = 0;
577 	if (swim3_readbit(fs, SEEK_COMPLETE)) {
578 		out_8(&sw->select, RELAX);
579 		fs->state = locating;
580 		act(fs);
581 		return;
582 	}
583 	out_8(&sw->select, RELAX);
584 	if (fs->settle_time < 2*HZ) {
585 		++fs->settle_time;
586 		set_timeout(fs, 1, settle_timeout);
587 		return;
588 	}
589 	printk(KERN_ERR "swim3: seek settle timeout\n");
590 	end_request(fd_req, 0);
591 	fs->state = idle;
592 	start_request(fs);
593 }
594 
595 static void xfer_timeout(unsigned long data)
596 {
597 	struct floppy_state *fs = (struct floppy_state *) data;
598 	struct swim3 __iomem *sw = fs->swim3;
599 	struct dbdma_regs __iomem *dr = fs->dma;
600 	struct dbdma_cmd *cp = fs->dma_cmd;
601 	unsigned long s;
602 	int n;
603 
604 	fs->timeout_pending = 0;
605 	out_le32(&dr->control, RUN << 16);
606 	/* We must wait a bit for dbdma to stop */
607 	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
608 		udelay(1);
609 	out_8(&sw->intr_enable, 0);
610 	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
611 	out_8(&sw->select, RELAX);
612 	if (rq_data_dir(fd_req) == WRITE)
613 		++cp;
614 	if (ld_le16(&cp->xfer_status) != 0)
615 		s = fs->scount - ((ld_le16(&cp->res_count) + 511) >> 9);
616 	else
617 		s = 0;
618 	fd_req->sector += s;
619 	fd_req->current_nr_sectors -= s;
620 	printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
621 	       (rq_data_dir(fd_req)==WRITE? "writ": "read"), (long)fd_req->sector);
622 	end_request(fd_req, 0);
623 	fs->state = idle;
624 	start_request(fs);
625 }
626 
627 static irqreturn_t swim3_interrupt(int irq, void *dev_id)
628 {
629 	struct floppy_state *fs = (struct floppy_state *) dev_id;
630 	struct swim3 __iomem *sw = fs->swim3;
631 	int intr, err, n;
632 	int stat, resid;
633 	struct dbdma_regs __iomem *dr;
634 	struct dbdma_cmd *cp;
635 
636 	intr = in_8(&sw->intr);
637 	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
638 	if ((intr & ERROR_INTR) && fs->state != do_transfer)
639 		printk(KERN_ERR "swim3_interrupt, state=%d, dir=%x, intr=%x, err=%x\n",
640 		       fs->state, rq_data_dir(fd_req), intr, err);
641 	switch (fs->state) {
642 	case locating:
643 		if (intr & SEEN_SECTOR) {
644 			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
645 			out_8(&sw->select, RELAX);
646 			out_8(&sw->intr_enable, 0);
647 			del_timer(&fs->timeout);
648 			fs->timeout_pending = 0;
649 			if (sw->ctrack == 0xff) {
650 				printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
651 				fs->cur_cyl = -1;
652 				if (fs->retries > 5) {
653 					end_request(fd_req, 0);
654 					fs->state = idle;
655 					start_request(fs);
656 				} else {
657 					fs->state = jogging;
658 					act(fs);
659 				}
660 				break;
661 			}
662 			fs->cur_cyl = sw->ctrack;
663 			fs->cur_sector = sw->csect;
664 			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
665 				printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
666 				       fs->expect_cyl, fs->cur_cyl);
667 			fs->state = do_transfer;
668 			act(fs);
669 		}
670 		break;
671 	case seeking:
672 	case jogging:
673 		if (sw->nseek == 0) {
674 			out_8(&sw->control_bic, DO_SEEK);
675 			out_8(&sw->select, RELAX);
676 			out_8(&sw->intr_enable, 0);
677 			del_timer(&fs->timeout);
678 			fs->timeout_pending = 0;
679 			if (fs->state == seeking)
680 				++fs->retries;
681 			fs->state = settling;
682 			act(fs);
683 		}
684 		break;
685 	case settling:
686 		out_8(&sw->intr_enable, 0);
687 		del_timer(&fs->timeout);
688 		fs->timeout_pending = 0;
689 		act(fs);
690 		break;
691 	case do_transfer:
692 		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
693 			break;
694 		out_8(&sw->intr_enable, 0);
695 		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
696 		out_8(&sw->select, RELAX);
697 		del_timer(&fs->timeout);
698 		fs->timeout_pending = 0;
699 		dr = fs->dma;
700 		cp = fs->dma_cmd;
701 		if (rq_data_dir(fd_req) == WRITE)
702 			++cp;
703 		/*
704 		 * Check that the main data transfer has finished.
705 		 * On writing, the swim3 sometimes doesn't use
706 		 * up all the bytes of the postamble, so we can still
707 		 * see DMA active here.  That doesn't matter as long
708 		 * as all the sector data has been transferred.
709 		 */
710 		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
711 			/* wait a little while for DMA to complete */
712 			for (n = 0; n < 100; ++n) {
713 				if (cp->xfer_status != 0)
714 					break;
715 				udelay(1);
716 				barrier();
717 			}
718 		}
719 		/* turn off DMA */
720 		out_le32(&dr->control, (RUN | PAUSE) << 16);
721 		stat = ld_le16(&cp->xfer_status);
722 		resid = ld_le16(&cp->res_count);
723 		if (intr & ERROR_INTR) {
724 			n = fs->scount - 1 - resid / 512;
725 			if (n > 0) {
726 				fd_req->sector += n;
727 				fd_req->current_nr_sectors -= n;
728 				fd_req->buffer += n * 512;
729 				fs->req_sector += n;
730 			}
731 			if (fs->retries < 5) {
732 				++fs->retries;
733 				act(fs);
734 			} else {
735 				printk("swim3: error %sing block %ld (err=%x)\n",
736 				       rq_data_dir(fd_req) == WRITE? "writ": "read",
737 				       (long)fd_req->sector, err);
738 				end_request(fd_req, 0);
739 				fs->state = idle;
740 			}
741 		} else {
742 			if ((stat & ACTIVE) == 0 || resid != 0) {
743 				/* musta been an error */
744 				printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
745 				printk(KERN_ERR "  state=%d, dir=%x, intr=%x, err=%x\n",
746 				       fs->state, rq_data_dir(fd_req), intr, err);
747 				end_request(fd_req, 0);
748 				fs->state = idle;
749 				start_request(fs);
750 				break;
751 			}
752 			fd_req->sector += fs->scount;
753 			fd_req->current_nr_sectors -= fs->scount;
754 			fd_req->buffer += fs->scount * 512;
755 			if (fd_req->current_nr_sectors <= 0) {
756 				end_request(fd_req, 1);
757 				fs->state = idle;
758 			} else {
759 				fs->req_sector += fs->scount;
760 				if (fs->req_sector > fs->secpertrack) {
761 					fs->req_sector -= fs->secpertrack;
762 					if (++fs->head > 1) {
763 						fs->head = 0;
764 						++fs->req_cyl;
765 					}
766 				}
767 				act(fs);
768 			}
769 		}
770 		if (fs->state == idle)
771 			start_request(fs);
772 		break;
773 	default:
774 		printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
775 	}
776 	return IRQ_HANDLED;
777 }
778 
779 /*
780 static void fd_dma_interrupt(int irq, void *dev_id)
781 {
782 }
783 */
784 
785 static int grab_drive(struct floppy_state *fs, enum swim_state state,
786 		      int interruptible)
787 {
788 	unsigned long flags;
789 
790 	spin_lock_irqsave(&fs->lock, flags);
791 	if (fs->state != idle) {
792 		++fs->wanted;
793 		while (fs->state != available) {
794 			if (interruptible && signal_pending(current)) {
795 				--fs->wanted;
796 				spin_unlock_irqrestore(&fs->lock, flags);
797 				return -EINTR;
798 			}
799 			interruptible_sleep_on(&fs->wait);
800 		}
801 		--fs->wanted;
802 	}
803 	fs->state = state;
804 	spin_unlock_irqrestore(&fs->lock, flags);
805 	return 0;
806 }
807 
808 static void release_drive(struct floppy_state *fs)
809 {
810 	unsigned long flags;
811 
812 	spin_lock_irqsave(&fs->lock, flags);
813 	fs->state = idle;
814 	start_request(fs);
815 	spin_unlock_irqrestore(&fs->lock, flags);
816 }
817 
818 static int fd_eject(struct floppy_state *fs)
819 {
820 	int err, n;
821 
822 	err = grab_drive(fs, ejecting, 1);
823 	if (err)
824 		return err;
825 	swim3_action(fs, EJECT);
826 	for (n = 20; n > 0; --n) {
827 		if (signal_pending(current)) {
828 			err = -EINTR;
829 			break;
830 		}
831 		swim3_select(fs, RELAX);
832 		schedule_timeout_interruptible(1);
833 		if (swim3_readbit(fs, DISK_IN) == 0)
834 			break;
835 	}
836 	swim3_select(fs, RELAX);
837 	udelay(150);
838 	fs->ejected = 1;
839 	release_drive(fs);
840 	return err;
841 }
842 
843 static struct floppy_struct floppy_type =
844 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
845 
846 static int floppy_ioctl(struct inode *inode, struct file *filp,
847 			unsigned int cmd, unsigned long param)
848 {
849 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
850 	int err;
851 
852 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
853 		return -EPERM;
854 
855 #ifdef CONFIG_PMAC_MEDIABAY
856 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
857 		return -ENXIO;
858 #endif
859 
860 	switch (cmd) {
861 	case FDEJECT:
862 		if (fs->ref_count != 1)
863 			return -EBUSY;
864 		err = fd_eject(fs);
865 		return err;
866 	case FDGETPRM:
867 	        if (copy_to_user((void __user *) param, &floppy_type,
868 				 sizeof(struct floppy_struct)))
869 			return -EFAULT;
870 		return 0;
871 	}
872 	return -ENOTTY;
873 }
874 
875 static int floppy_open(struct inode *inode, struct file *filp)
876 {
877 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
878 	struct swim3 __iomem *sw = fs->swim3;
879 	int n, err = 0;
880 
881 	if (fs->ref_count == 0) {
882 #ifdef CONFIG_PMAC_MEDIABAY
883 		if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
884 			return -ENXIO;
885 #endif
886 		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
887 		out_8(&sw->control_bic, 0xff);
888 		out_8(&sw->mode, 0x95);
889 		udelay(10);
890 		out_8(&sw->intr_enable, 0);
891 		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
892 		swim3_action(fs, MOTOR_ON);
893 		fs->write_prot = -1;
894 		fs->cur_cyl = -1;
895 		for (n = 0; n < 2 * HZ; ++n) {
896 			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
897 				break;
898 			if (signal_pending(current)) {
899 				err = -EINTR;
900 				break;
901 			}
902 			swim3_select(fs, RELAX);
903 			schedule_timeout_interruptible(1);
904 		}
905 		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
906 				 || swim3_readbit(fs, DISK_IN) == 0))
907 			err = -ENXIO;
908 		swim3_action(fs, SETMFM);
909 		swim3_select(fs, RELAX);
910 
911 	} else if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
912 		return -EBUSY;
913 
914 	if (err == 0 && (filp->f_flags & O_NDELAY) == 0
915 	    && (filp->f_mode & 3)) {
916 		check_disk_change(inode->i_bdev);
917 		if (fs->ejected)
918 			err = -ENXIO;
919 	}
920 
921 	if (err == 0 && (filp->f_mode & 2)) {
922 		if (fs->write_prot < 0)
923 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
924 		if (fs->write_prot)
925 			err = -EROFS;
926 	}
927 
928 	if (err) {
929 		if (fs->ref_count == 0) {
930 			swim3_action(fs, MOTOR_OFF);
931 			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
932 			swim3_select(fs, RELAX);
933 		}
934 		return err;
935 	}
936 
937 	if (filp->f_flags & O_EXCL)
938 		fs->ref_count = -1;
939 	else
940 		++fs->ref_count;
941 
942 	return 0;
943 }
944 
945 static int floppy_release(struct inode *inode, struct file *filp)
946 {
947 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
948 	struct swim3 __iomem *sw = fs->swim3;
949 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
950 		swim3_action(fs, MOTOR_OFF);
951 		out_8(&sw->control_bic, 0xff);
952 		swim3_select(fs, RELAX);
953 	}
954 	return 0;
955 }
956 
957 static int floppy_check_change(struct gendisk *disk)
958 {
959 	struct floppy_state *fs = disk->private_data;
960 	return fs->ejected;
961 }
962 
963 static int floppy_revalidate(struct gendisk *disk)
964 {
965 	struct floppy_state *fs = disk->private_data;
966 	struct swim3 __iomem *sw;
967 	int ret, n;
968 
969 #ifdef CONFIG_PMAC_MEDIABAY
970 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
971 		return -ENXIO;
972 #endif
973 
974 	sw = fs->swim3;
975 	grab_drive(fs, revalidating, 0);
976 	out_8(&sw->intr_enable, 0);
977 	out_8(&sw->control_bis, DRIVE_ENABLE);
978 	swim3_action(fs, MOTOR_ON);	/* necessary? */
979 	fs->write_prot = -1;
980 	fs->cur_cyl = -1;
981 	mdelay(1);
982 	for (n = HZ; n > 0; --n) {
983 		if (swim3_readbit(fs, SEEK_COMPLETE))
984 			break;
985 		if (signal_pending(current))
986 			break;
987 		swim3_select(fs, RELAX);
988 		schedule_timeout_interruptible(1);
989 	}
990 	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
991 		|| swim3_readbit(fs, DISK_IN) == 0;
992 	if (ret)
993 		swim3_action(fs, MOTOR_OFF);
994 	else {
995 		fs->ejected = 0;
996 		swim3_action(fs, SETMFM);
997 	}
998 	swim3_select(fs, RELAX);
999 
1000 	release_drive(fs);
1001 	return ret;
1002 }
1003 
1004 static struct block_device_operations floppy_fops = {
1005 	.open		= floppy_open,
1006 	.release	= floppy_release,
1007 	.ioctl		= floppy_ioctl,
1008 	.media_changed	= floppy_check_change,
1009 	.revalidate_disk= floppy_revalidate,
1010 };
1011 
1012 static int swim3_add_device(struct macio_dev *mdev, int index)
1013 {
1014 	struct device_node *swim = mdev->ofdev.node;
1015 	struct device_node *mediabay;
1016 	struct floppy_state *fs = &floppy_states[index];
1017 	int rc = -EBUSY;
1018 
1019 	/* Check & Request resources */
1020 	if (macio_resource_count(mdev) < 2) {
1021 		printk(KERN_WARNING "ifd%d: no address for %s\n",
1022 		       index, swim->full_name);
1023 		return -ENXIO;
1024 	}
1025 	if (macio_irq_count(mdev) < 2) {
1026 		printk(KERN_WARNING "fd%d: no intrs for device %s\n",
1027 			index, swim->full_name);
1028 	}
1029 	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1030 		printk(KERN_ERR "fd%d: can't request mmio resource for %s\n",
1031 		       index, swim->full_name);
1032 		return -EBUSY;
1033 	}
1034 	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1035 		printk(KERN_ERR "fd%d: can't request dma resource for %s\n",
1036 		       index, swim->full_name);
1037 		macio_release_resource(mdev, 0);
1038 		return -EBUSY;
1039 	}
1040 	dev_set_drvdata(&mdev->ofdev.dev, fs);
1041 
1042 	mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ?
1043 		swim->parent : NULL;
1044 	if (mediabay == NULL)
1045 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1046 
1047 	memset(fs, 0, sizeof(*fs));
1048 	spin_lock_init(&fs->lock);
1049 	fs->state = idle;
1050 	fs->swim3 = (struct swim3 __iomem *)
1051 		ioremap(macio_resource_start(mdev, 0), 0x200);
1052 	if (fs->swim3 == NULL) {
1053 		printk("fd%d: couldn't map registers for %s\n",
1054 		       index, swim->full_name);
1055 		rc = -ENOMEM;
1056 		goto out_release;
1057 	}
1058 	fs->dma = (struct dbdma_regs __iomem *)
1059 		ioremap(macio_resource_start(mdev, 1), 0x200);
1060 	if (fs->dma == NULL) {
1061 		printk("fd%d: couldn't map DMA for %s\n",
1062 		       index, swim->full_name);
1063 		iounmap(fs->swim3);
1064 		rc = -ENOMEM;
1065 		goto out_release;
1066 	}
1067 	fs->swim3_intr = macio_irq(mdev, 0);
1068 	fs->dma_intr = macio_irq(mdev, 1);;
1069 	fs->cur_cyl = -1;
1070 	fs->cur_sector = -1;
1071 	fs->secpercyl = 36;
1072 	fs->secpertrack = 18;
1073 	fs->total_secs = 2880;
1074 	fs->media_bay = mediabay;
1075 	init_waitqueue_head(&fs->wait);
1076 
1077 	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1078 	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1079 	st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1080 
1081 	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1082 		printk(KERN_ERR "fd%d: couldn't request irq %d for %s\n",
1083 		       index, fs->swim3_intr, swim->full_name);
1084 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1085 		goto out_unmap;
1086 		return -EBUSY;
1087 	}
1088 /*
1089 	if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1090 		printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1091 		       fs->dma_intr);
1092 		return -EBUSY;
1093 	}
1094 */
1095 
1096 	init_timer(&fs->timeout);
1097 
1098 	printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1099 		mediabay ? "in media bay" : "");
1100 
1101 	return 0;
1102 
1103  out_unmap:
1104 	iounmap(fs->dma);
1105 	iounmap(fs->swim3);
1106 
1107  out_release:
1108 	macio_release_resource(mdev, 0);
1109 	macio_release_resource(mdev, 1);
1110 
1111 	return rc;
1112 }
1113 
1114 static int __devinit swim3_attach(struct macio_dev *mdev, const struct of_device_id *match)
1115 {
1116 	int i, rc;
1117 	struct gendisk *disk;
1118 
1119 	/* Add the drive */
1120 	rc = swim3_add_device(mdev, floppy_count);
1121 	if (rc)
1122 		return rc;
1123 
1124 	/* Now create the queue if not there yet */
1125 	if (swim3_queue == NULL) {
1126 		/* If we failed, there isn't much we can do as the driver is still
1127 		 * too dumb to remove the device, just bail out
1128 		 */
1129 		if (register_blkdev(FLOPPY_MAJOR, "fd"))
1130 			return 0;
1131 		swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1132 		if (swim3_queue == NULL) {
1133 			unregister_blkdev(FLOPPY_MAJOR, "fd");
1134 			return 0;
1135 		}
1136 	}
1137 
1138 	/* Now register that disk. Same comment about failure handling */
1139 	i = floppy_count++;
1140 	disk = disks[i] = alloc_disk(1);
1141 	if (disk == NULL)
1142 		return 0;
1143 
1144 	disk->major = FLOPPY_MAJOR;
1145 	disk->first_minor = i;
1146 	disk->fops = &floppy_fops;
1147 	disk->private_data = &floppy_states[i];
1148 	disk->queue = swim3_queue;
1149 	disk->flags |= GENHD_FL_REMOVABLE;
1150 	sprintf(disk->disk_name, "fd%d", i);
1151 	set_capacity(disk, 2880);
1152 	add_disk(disk);
1153 
1154 	return 0;
1155 }
1156 
1157 static struct of_device_id swim3_match[] =
1158 {
1159 	{
1160 	.name		= "swim3",
1161 	},
1162 	{
1163 	.compatible	= "ohare-swim3"
1164 	},
1165 	{
1166 	.compatible	= "swim3"
1167 	},
1168 };
1169 
1170 static struct macio_driver swim3_driver =
1171 {
1172 	.name 		= "swim3",
1173 	.match_table	= swim3_match,
1174 	.probe		= swim3_attach,
1175 #if 0
1176 	.suspend	= swim3_suspend,
1177 	.resume		= swim3_resume,
1178 #endif
1179 };
1180 
1181 
1182 int swim3_init(void)
1183 {
1184 	macio_register_driver(&swim3_driver);
1185 	return 0;
1186 }
1187 
1188 module_init(swim3_init)
1189 
1190 MODULE_LICENSE("GPL");
1191 MODULE_AUTHOR("Paul Mackerras");
1192 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1193