xref: /openbmc/linux/drivers/block/swim3.c (revision 22246614)
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 static void swim3_select(struct floppy_state *fs, int sel)
255 {
256 	struct swim3 __iomem *sw = fs->swim3;
257 
258 	out_8(&sw->select, RELAX);
259 	if (sel & 8)
260 		out_8(&sw->control_bis, SELECT);
261 	else
262 		out_8(&sw->control_bic, SELECT);
263 	out_8(&sw->select, sel & CA_MASK);
264 }
265 
266 static void swim3_action(struct floppy_state *fs, int action)
267 {
268 	struct swim3 __iomem *sw = fs->swim3;
269 
270 	swim3_select(fs, action);
271 	udelay(1);
272 	out_8(&sw->select, sw->select | LSTRB);
273 	udelay(2);
274 	out_8(&sw->select, sw->select & ~LSTRB);
275 	udelay(1);
276 }
277 
278 static int swim3_readbit(struct floppy_state *fs, int bit)
279 {
280 	struct swim3 __iomem *sw = fs->swim3;
281 	int stat;
282 
283 	swim3_select(fs, bit);
284 	udelay(1);
285 	stat = in_8(&sw->status);
286 	return (stat & DATA) == 0;
287 }
288 
289 static void do_fd_request(struct request_queue * q)
290 {
291 	int i;
292 	for(i=0;i<floppy_count;i++)
293 	{
294 #ifdef CONFIG_PMAC_MEDIABAY
295 		if (floppy_states[i].media_bay &&
296 			check_media_bay(floppy_states[i].media_bay, MB_FD))
297 			continue;
298 #endif /* CONFIG_PMAC_MEDIABAY */
299 		start_request(&floppy_states[i]);
300 	}
301 }
302 
303 static void start_request(struct floppy_state *fs)
304 {
305 	struct request *req;
306 	unsigned long x;
307 
308 	if (fs->state == idle && fs->wanted) {
309 		fs->state = available;
310 		wake_up(&fs->wait);
311 		return;
312 	}
313 	while (fs->state == idle && (req = elv_next_request(swim3_queue))) {
314 #if 0
315 		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
316 		       req->rq_disk->disk_name, req->cmd,
317 		       (long)req->sector, req->nr_sectors, req->buffer);
318 		printk("           errors=%d current_nr_sectors=%ld\n",
319 		       req->errors, req->current_nr_sectors);
320 #endif
321 
322 		if (req->sector < 0 || req->sector >= fs->total_secs) {
323 			end_request(req, 0);
324 			continue;
325 		}
326 		if (req->current_nr_sectors == 0) {
327 			end_request(req, 1);
328 			continue;
329 		}
330 		if (fs->ejected) {
331 			end_request(req, 0);
332 			continue;
333 		}
334 
335 		if (rq_data_dir(req) == WRITE) {
336 			if (fs->write_prot < 0)
337 				fs->write_prot = swim3_readbit(fs, WRITE_PROT);
338 			if (fs->write_prot) {
339 				end_request(req, 0);
340 				continue;
341 			}
342 		}
343 
344 		/* Do not remove the cast. req->sector is now a sector_t and
345 		 * can be 64 bits, but it will never go past 32 bits for this
346 		 * driver anyway, so we can safely cast it down and not have
347 		 * to do a 64/32 division
348 		 */
349 		fs->req_cyl = ((long)req->sector) / fs->secpercyl;
350 		x = ((long)req->sector) % fs->secpercyl;
351 		fs->head = x / fs->secpertrack;
352 		fs->req_sector = x % fs->secpertrack + 1;
353 		fd_req = req;
354 		fs->state = do_transfer;
355 		fs->retries = 0;
356 
357 		act(fs);
358 	}
359 }
360 
361 static void set_timeout(struct floppy_state *fs, int nticks,
362 			void (*proc)(unsigned long))
363 {
364 	unsigned long flags;
365 
366 	spin_lock_irqsave(&fs->lock, flags);
367 	if (fs->timeout_pending)
368 		del_timer(&fs->timeout);
369 	fs->timeout.expires = jiffies + nticks;
370 	fs->timeout.function = proc;
371 	fs->timeout.data = (unsigned long) fs;
372 	add_timer(&fs->timeout);
373 	fs->timeout_pending = 1;
374 	spin_unlock_irqrestore(&fs->lock, flags);
375 }
376 
377 static inline void scan_track(struct floppy_state *fs)
378 {
379 	struct swim3 __iomem *sw = fs->swim3;
380 
381 	swim3_select(fs, READ_DATA_0);
382 	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
383 	in_8(&sw->error);
384 	out_8(&sw->intr_enable, SEEN_SECTOR);
385 	out_8(&sw->control_bis, DO_ACTION);
386 	/* enable intr when track found */
387 	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
388 }
389 
390 static inline void seek_track(struct floppy_state *fs, int n)
391 {
392 	struct swim3 __iomem *sw = fs->swim3;
393 
394 	if (n >= 0) {
395 		swim3_action(fs, SEEK_POSITIVE);
396 		sw->nseek = n;
397 	} else {
398 		swim3_action(fs, SEEK_NEGATIVE);
399 		sw->nseek = -n;
400 	}
401 	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
402 	swim3_select(fs, STEP);
403 	in_8(&sw->error);
404 	/* enable intr when seek finished */
405 	out_8(&sw->intr_enable, SEEK_DONE);
406 	out_8(&sw->control_bis, DO_SEEK);
407 	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
408 	fs->settle_time = 0;
409 }
410 
411 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
412 			    void *buf, int count)
413 {
414 	st_le16(&cp->req_count, count);
415 	st_le16(&cp->command, cmd);
416 	st_le32(&cp->phy_addr, virt_to_bus(buf));
417 	cp->xfer_status = 0;
418 }
419 
420 static inline void setup_transfer(struct floppy_state *fs)
421 {
422 	int n;
423 	struct swim3 __iomem *sw = fs->swim3;
424 	struct dbdma_cmd *cp = fs->dma_cmd;
425 	struct dbdma_regs __iomem *dr = fs->dma;
426 
427 	if (fd_req->current_nr_sectors <= 0) {
428 		printk(KERN_ERR "swim3: transfer 0 sectors?\n");
429 		return;
430 	}
431 	if (rq_data_dir(fd_req) == WRITE)
432 		n = 1;
433 	else {
434 		n = fs->secpertrack - fs->req_sector + 1;
435 		if (n > fd_req->current_nr_sectors)
436 			n = fd_req->current_nr_sectors;
437 	}
438 	fs->scount = n;
439 	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
440 	out_8(&sw->sector, fs->req_sector);
441 	out_8(&sw->nsect, n);
442 	out_8(&sw->gap3, 0);
443 	out_le32(&dr->cmdptr, virt_to_bus(cp));
444 	if (rq_data_dir(fd_req) == WRITE) {
445 		/* Set up 3 dma commands: write preamble, data, postamble */
446 		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
447 		++cp;
448 		init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
449 		++cp;
450 		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
451 	} else {
452 		init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
453 	}
454 	++cp;
455 	out_le16(&cp->command, DBDMA_STOP);
456 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
457 	in_8(&sw->error);
458 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
459 	if (rq_data_dir(fd_req) == WRITE)
460 		out_8(&sw->control_bis, WRITE_SECTORS);
461 	in_8(&sw->intr);
462 	out_le32(&dr->control, (RUN << 16) | RUN);
463 	/* enable intr when transfer complete */
464 	out_8(&sw->intr_enable, TRANSFER_DONE);
465 	out_8(&sw->control_bis, DO_ACTION);
466 	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
467 }
468 
469 static void act(struct floppy_state *fs)
470 {
471 	for (;;) {
472 		switch (fs->state) {
473 		case idle:
474 			return;		/* XXX shouldn't get here */
475 
476 		case locating:
477 			if (swim3_readbit(fs, TRACK_ZERO)) {
478 				fs->cur_cyl = 0;
479 				if (fs->req_cyl == 0)
480 					fs->state = do_transfer;
481 				else
482 					fs->state = seeking;
483 				break;
484 			}
485 			scan_track(fs);
486 			return;
487 
488 		case seeking:
489 			if (fs->cur_cyl < 0) {
490 				fs->expect_cyl = -1;
491 				fs->state = locating;
492 				break;
493 			}
494 			if (fs->req_cyl == fs->cur_cyl) {
495 				printk("whoops, seeking 0\n");
496 				fs->state = do_transfer;
497 				break;
498 			}
499 			seek_track(fs, fs->req_cyl - fs->cur_cyl);
500 			return;
501 
502 		case settling:
503 			/* check for SEEK_COMPLETE after 30ms */
504 			fs->settle_time = (HZ + 32) / 33;
505 			set_timeout(fs, fs->settle_time, settle_timeout);
506 			return;
507 
508 		case do_transfer:
509 			if (fs->cur_cyl != fs->req_cyl) {
510 				if (fs->retries > 5) {
511 					end_request(fd_req, 0);
512 					fs->state = idle;
513 					return;
514 				}
515 				fs->state = seeking;
516 				break;
517 			}
518 			setup_transfer(fs);
519 			return;
520 
521 		case jogging:
522 			seek_track(fs, -5);
523 			return;
524 
525 		default:
526 			printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
527 			return;
528 		}
529 	}
530 }
531 
532 static void scan_timeout(unsigned long data)
533 {
534 	struct floppy_state *fs = (struct floppy_state *) data;
535 	struct swim3 __iomem *sw = fs->swim3;
536 
537 	fs->timeout_pending = 0;
538 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
539 	out_8(&sw->select, RELAX);
540 	out_8(&sw->intr_enable, 0);
541 	fs->cur_cyl = -1;
542 	if (fs->retries > 5) {
543 		end_request(fd_req, 0);
544 		fs->state = idle;
545 		start_request(fs);
546 	} else {
547 		fs->state = jogging;
548 		act(fs);
549 	}
550 }
551 
552 static void seek_timeout(unsigned long data)
553 {
554 	struct floppy_state *fs = (struct floppy_state *) data;
555 	struct swim3 __iomem *sw = fs->swim3;
556 
557 	fs->timeout_pending = 0;
558 	out_8(&sw->control_bic, DO_SEEK);
559 	out_8(&sw->select, RELAX);
560 	out_8(&sw->intr_enable, 0);
561 	printk(KERN_ERR "swim3: seek timeout\n");
562 	end_request(fd_req, 0);
563 	fs->state = idle;
564 	start_request(fs);
565 }
566 
567 static void settle_timeout(unsigned long data)
568 {
569 	struct floppy_state *fs = (struct floppy_state *) data;
570 	struct swim3 __iomem *sw = fs->swim3;
571 
572 	fs->timeout_pending = 0;
573 	if (swim3_readbit(fs, SEEK_COMPLETE)) {
574 		out_8(&sw->select, RELAX);
575 		fs->state = locating;
576 		act(fs);
577 		return;
578 	}
579 	out_8(&sw->select, RELAX);
580 	if (fs->settle_time < 2*HZ) {
581 		++fs->settle_time;
582 		set_timeout(fs, 1, settle_timeout);
583 		return;
584 	}
585 	printk(KERN_ERR "swim3: seek settle timeout\n");
586 	end_request(fd_req, 0);
587 	fs->state = idle;
588 	start_request(fs);
589 }
590 
591 static void xfer_timeout(unsigned long data)
592 {
593 	struct floppy_state *fs = (struct floppy_state *) data;
594 	struct swim3 __iomem *sw = fs->swim3;
595 	struct dbdma_regs __iomem *dr = fs->dma;
596 	struct dbdma_cmd *cp = fs->dma_cmd;
597 	unsigned long s;
598 	int n;
599 
600 	fs->timeout_pending = 0;
601 	out_le32(&dr->control, RUN << 16);
602 	/* We must wait a bit for dbdma to stop */
603 	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
604 		udelay(1);
605 	out_8(&sw->intr_enable, 0);
606 	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
607 	out_8(&sw->select, RELAX);
608 	if (rq_data_dir(fd_req) == WRITE)
609 		++cp;
610 	if (ld_le16(&cp->xfer_status) != 0)
611 		s = fs->scount - ((ld_le16(&cp->res_count) + 511) >> 9);
612 	else
613 		s = 0;
614 	fd_req->sector += s;
615 	fd_req->current_nr_sectors -= s;
616 	printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
617 	       (rq_data_dir(fd_req)==WRITE? "writ": "read"), (long)fd_req->sector);
618 	end_request(fd_req, 0);
619 	fs->state = idle;
620 	start_request(fs);
621 }
622 
623 static irqreturn_t swim3_interrupt(int irq, void *dev_id)
624 {
625 	struct floppy_state *fs = (struct floppy_state *) dev_id;
626 	struct swim3 __iomem *sw = fs->swim3;
627 	int intr, err, n;
628 	int stat, resid;
629 	struct dbdma_regs __iomem *dr;
630 	struct dbdma_cmd *cp;
631 
632 	intr = in_8(&sw->intr);
633 	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
634 	if ((intr & ERROR_INTR) && fs->state != do_transfer)
635 		printk(KERN_ERR "swim3_interrupt, state=%d, dir=%x, intr=%x, err=%x\n",
636 		       fs->state, rq_data_dir(fd_req), intr, err);
637 	switch (fs->state) {
638 	case locating:
639 		if (intr & SEEN_SECTOR) {
640 			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
641 			out_8(&sw->select, RELAX);
642 			out_8(&sw->intr_enable, 0);
643 			del_timer(&fs->timeout);
644 			fs->timeout_pending = 0;
645 			if (sw->ctrack == 0xff) {
646 				printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
647 				fs->cur_cyl = -1;
648 				if (fs->retries > 5) {
649 					end_request(fd_req, 0);
650 					fs->state = idle;
651 					start_request(fs);
652 				} else {
653 					fs->state = jogging;
654 					act(fs);
655 				}
656 				break;
657 			}
658 			fs->cur_cyl = sw->ctrack;
659 			fs->cur_sector = sw->csect;
660 			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
661 				printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
662 				       fs->expect_cyl, fs->cur_cyl);
663 			fs->state = do_transfer;
664 			act(fs);
665 		}
666 		break;
667 	case seeking:
668 	case jogging:
669 		if (sw->nseek == 0) {
670 			out_8(&sw->control_bic, DO_SEEK);
671 			out_8(&sw->select, RELAX);
672 			out_8(&sw->intr_enable, 0);
673 			del_timer(&fs->timeout);
674 			fs->timeout_pending = 0;
675 			if (fs->state == seeking)
676 				++fs->retries;
677 			fs->state = settling;
678 			act(fs);
679 		}
680 		break;
681 	case settling:
682 		out_8(&sw->intr_enable, 0);
683 		del_timer(&fs->timeout);
684 		fs->timeout_pending = 0;
685 		act(fs);
686 		break;
687 	case do_transfer:
688 		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
689 			break;
690 		out_8(&sw->intr_enable, 0);
691 		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
692 		out_8(&sw->select, RELAX);
693 		del_timer(&fs->timeout);
694 		fs->timeout_pending = 0;
695 		dr = fs->dma;
696 		cp = fs->dma_cmd;
697 		if (rq_data_dir(fd_req) == WRITE)
698 			++cp;
699 		/*
700 		 * Check that the main data transfer has finished.
701 		 * On writing, the swim3 sometimes doesn't use
702 		 * up all the bytes of the postamble, so we can still
703 		 * see DMA active here.  That doesn't matter as long
704 		 * as all the sector data has been transferred.
705 		 */
706 		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
707 			/* wait a little while for DMA to complete */
708 			for (n = 0; n < 100; ++n) {
709 				if (cp->xfer_status != 0)
710 					break;
711 				udelay(1);
712 				barrier();
713 			}
714 		}
715 		/* turn off DMA */
716 		out_le32(&dr->control, (RUN | PAUSE) << 16);
717 		stat = ld_le16(&cp->xfer_status);
718 		resid = ld_le16(&cp->res_count);
719 		if (intr & ERROR_INTR) {
720 			n = fs->scount - 1 - resid / 512;
721 			if (n > 0) {
722 				fd_req->sector += n;
723 				fd_req->current_nr_sectors -= n;
724 				fd_req->buffer += n * 512;
725 				fs->req_sector += n;
726 			}
727 			if (fs->retries < 5) {
728 				++fs->retries;
729 				act(fs);
730 			} else {
731 				printk("swim3: error %sing block %ld (err=%x)\n",
732 				       rq_data_dir(fd_req) == WRITE? "writ": "read",
733 				       (long)fd_req->sector, err);
734 				end_request(fd_req, 0);
735 				fs->state = idle;
736 			}
737 		} else {
738 			if ((stat & ACTIVE) == 0 || resid != 0) {
739 				/* musta been an error */
740 				printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
741 				printk(KERN_ERR "  state=%d, dir=%x, intr=%x, err=%x\n",
742 				       fs->state, rq_data_dir(fd_req), intr, err);
743 				end_request(fd_req, 0);
744 				fs->state = idle;
745 				start_request(fs);
746 				break;
747 			}
748 			fd_req->sector += fs->scount;
749 			fd_req->current_nr_sectors -= fs->scount;
750 			fd_req->buffer += fs->scount * 512;
751 			if (fd_req->current_nr_sectors <= 0) {
752 				end_request(fd_req, 1);
753 				fs->state = idle;
754 			} else {
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 			}
765 		}
766 		if (fs->state == idle)
767 			start_request(fs);
768 		break;
769 	default:
770 		printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
771 	}
772 	return IRQ_HANDLED;
773 }
774 
775 /*
776 static void fd_dma_interrupt(int irq, void *dev_id)
777 {
778 }
779 */
780 
781 static int grab_drive(struct floppy_state *fs, enum swim_state state,
782 		      int interruptible)
783 {
784 	unsigned long flags;
785 
786 	spin_lock_irqsave(&fs->lock, flags);
787 	if (fs->state != idle) {
788 		++fs->wanted;
789 		while (fs->state != available) {
790 			if (interruptible && signal_pending(current)) {
791 				--fs->wanted;
792 				spin_unlock_irqrestore(&fs->lock, flags);
793 				return -EINTR;
794 			}
795 			interruptible_sleep_on(&fs->wait);
796 		}
797 		--fs->wanted;
798 	}
799 	fs->state = state;
800 	spin_unlock_irqrestore(&fs->lock, flags);
801 	return 0;
802 }
803 
804 static void release_drive(struct floppy_state *fs)
805 {
806 	unsigned long flags;
807 
808 	spin_lock_irqsave(&fs->lock, flags);
809 	fs->state = idle;
810 	start_request(fs);
811 	spin_unlock_irqrestore(&fs->lock, flags);
812 }
813 
814 static int fd_eject(struct floppy_state *fs)
815 {
816 	int err, n;
817 
818 	err = grab_drive(fs, ejecting, 1);
819 	if (err)
820 		return err;
821 	swim3_action(fs, EJECT);
822 	for (n = 20; n > 0; --n) {
823 		if (signal_pending(current)) {
824 			err = -EINTR;
825 			break;
826 		}
827 		swim3_select(fs, RELAX);
828 		schedule_timeout_interruptible(1);
829 		if (swim3_readbit(fs, DISK_IN) == 0)
830 			break;
831 	}
832 	swim3_select(fs, RELAX);
833 	udelay(150);
834 	fs->ejected = 1;
835 	release_drive(fs);
836 	return err;
837 }
838 
839 static struct floppy_struct floppy_type =
840 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
841 
842 static int floppy_ioctl(struct inode *inode, struct file *filp,
843 			unsigned int cmd, unsigned long param)
844 {
845 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
846 	int err;
847 
848 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
849 		return -EPERM;
850 
851 #ifdef CONFIG_PMAC_MEDIABAY
852 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
853 		return -ENXIO;
854 #endif
855 
856 	switch (cmd) {
857 	case FDEJECT:
858 		if (fs->ref_count != 1)
859 			return -EBUSY;
860 		err = fd_eject(fs);
861 		return err;
862 	case FDGETPRM:
863 	        if (copy_to_user((void __user *) param, &floppy_type,
864 				 sizeof(struct floppy_struct)))
865 			return -EFAULT;
866 		return 0;
867 	}
868 	return -ENOTTY;
869 }
870 
871 static int floppy_open(struct inode *inode, struct file *filp)
872 {
873 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
874 	struct swim3 __iomem *sw = fs->swim3;
875 	int n, err = 0;
876 
877 	if (fs->ref_count == 0) {
878 #ifdef CONFIG_PMAC_MEDIABAY
879 		if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
880 			return -ENXIO;
881 #endif
882 		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
883 		out_8(&sw->control_bic, 0xff);
884 		out_8(&sw->mode, 0x95);
885 		udelay(10);
886 		out_8(&sw->intr_enable, 0);
887 		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
888 		swim3_action(fs, MOTOR_ON);
889 		fs->write_prot = -1;
890 		fs->cur_cyl = -1;
891 		for (n = 0; n < 2 * HZ; ++n) {
892 			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
893 				break;
894 			if (signal_pending(current)) {
895 				err = -EINTR;
896 				break;
897 			}
898 			swim3_select(fs, RELAX);
899 			schedule_timeout_interruptible(1);
900 		}
901 		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
902 				 || swim3_readbit(fs, DISK_IN) == 0))
903 			err = -ENXIO;
904 		swim3_action(fs, SETMFM);
905 		swim3_select(fs, RELAX);
906 
907 	} else if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
908 		return -EBUSY;
909 
910 	if (err == 0 && (filp->f_flags & O_NDELAY) == 0
911 	    && (filp->f_mode & 3)) {
912 		check_disk_change(inode->i_bdev);
913 		if (fs->ejected)
914 			err = -ENXIO;
915 	}
916 
917 	if (err == 0 && (filp->f_mode & 2)) {
918 		if (fs->write_prot < 0)
919 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
920 		if (fs->write_prot)
921 			err = -EROFS;
922 	}
923 
924 	if (err) {
925 		if (fs->ref_count == 0) {
926 			swim3_action(fs, MOTOR_OFF);
927 			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
928 			swim3_select(fs, RELAX);
929 		}
930 		return err;
931 	}
932 
933 	if (filp->f_flags & O_EXCL)
934 		fs->ref_count = -1;
935 	else
936 		++fs->ref_count;
937 
938 	return 0;
939 }
940 
941 static int floppy_release(struct inode *inode, struct file *filp)
942 {
943 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
944 	struct swim3 __iomem *sw = fs->swim3;
945 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
946 		swim3_action(fs, MOTOR_OFF);
947 		out_8(&sw->control_bic, 0xff);
948 		swim3_select(fs, RELAX);
949 	}
950 	return 0;
951 }
952 
953 static int floppy_check_change(struct gendisk *disk)
954 {
955 	struct floppy_state *fs = disk->private_data;
956 	return fs->ejected;
957 }
958 
959 static int floppy_revalidate(struct gendisk *disk)
960 {
961 	struct floppy_state *fs = disk->private_data;
962 	struct swim3 __iomem *sw;
963 	int ret, n;
964 
965 #ifdef CONFIG_PMAC_MEDIABAY
966 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
967 		return -ENXIO;
968 #endif
969 
970 	sw = fs->swim3;
971 	grab_drive(fs, revalidating, 0);
972 	out_8(&sw->intr_enable, 0);
973 	out_8(&sw->control_bis, DRIVE_ENABLE);
974 	swim3_action(fs, MOTOR_ON);	/* necessary? */
975 	fs->write_prot = -1;
976 	fs->cur_cyl = -1;
977 	mdelay(1);
978 	for (n = HZ; n > 0; --n) {
979 		if (swim3_readbit(fs, SEEK_COMPLETE))
980 			break;
981 		if (signal_pending(current))
982 			break;
983 		swim3_select(fs, RELAX);
984 		schedule_timeout_interruptible(1);
985 	}
986 	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
987 		|| swim3_readbit(fs, DISK_IN) == 0;
988 	if (ret)
989 		swim3_action(fs, MOTOR_OFF);
990 	else {
991 		fs->ejected = 0;
992 		swim3_action(fs, SETMFM);
993 	}
994 	swim3_select(fs, RELAX);
995 
996 	release_drive(fs);
997 	return ret;
998 }
999 
1000 static struct block_device_operations floppy_fops = {
1001 	.open		= floppy_open,
1002 	.release	= floppy_release,
1003 	.ioctl		= floppy_ioctl,
1004 	.media_changed	= floppy_check_change,
1005 	.revalidate_disk= floppy_revalidate,
1006 };
1007 
1008 static int swim3_add_device(struct macio_dev *mdev, int index)
1009 {
1010 	struct device_node *swim = mdev->ofdev.node;
1011 	struct device_node *mediabay;
1012 	struct floppy_state *fs = &floppy_states[index];
1013 	int rc = -EBUSY;
1014 
1015 	/* Check & Request resources */
1016 	if (macio_resource_count(mdev) < 2) {
1017 		printk(KERN_WARNING "ifd%d: no address for %s\n",
1018 		       index, swim->full_name);
1019 		return -ENXIO;
1020 	}
1021 	if (macio_irq_count(mdev) < 2) {
1022 		printk(KERN_WARNING "fd%d: no intrs for device %s\n",
1023 			index, swim->full_name);
1024 	}
1025 	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1026 		printk(KERN_ERR "fd%d: can't request mmio resource for %s\n",
1027 		       index, swim->full_name);
1028 		return -EBUSY;
1029 	}
1030 	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1031 		printk(KERN_ERR "fd%d: can't request dma resource for %s\n",
1032 		       index, swim->full_name);
1033 		macio_release_resource(mdev, 0);
1034 		return -EBUSY;
1035 	}
1036 	dev_set_drvdata(&mdev->ofdev.dev, fs);
1037 
1038 	mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ?
1039 		swim->parent : NULL;
1040 	if (mediabay == NULL)
1041 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1042 
1043 	memset(fs, 0, sizeof(*fs));
1044 	spin_lock_init(&fs->lock);
1045 	fs->state = idle;
1046 	fs->swim3 = (struct swim3 __iomem *)
1047 		ioremap(macio_resource_start(mdev, 0), 0x200);
1048 	if (fs->swim3 == NULL) {
1049 		printk("fd%d: couldn't map registers for %s\n",
1050 		       index, swim->full_name);
1051 		rc = -ENOMEM;
1052 		goto out_release;
1053 	}
1054 	fs->dma = (struct dbdma_regs __iomem *)
1055 		ioremap(macio_resource_start(mdev, 1), 0x200);
1056 	if (fs->dma == NULL) {
1057 		printk("fd%d: couldn't map DMA for %s\n",
1058 		       index, swim->full_name);
1059 		iounmap(fs->swim3);
1060 		rc = -ENOMEM;
1061 		goto out_release;
1062 	}
1063 	fs->swim3_intr = macio_irq(mdev, 0);
1064 	fs->dma_intr = macio_irq(mdev, 1);;
1065 	fs->cur_cyl = -1;
1066 	fs->cur_sector = -1;
1067 	fs->secpercyl = 36;
1068 	fs->secpertrack = 18;
1069 	fs->total_secs = 2880;
1070 	fs->media_bay = mediabay;
1071 	init_waitqueue_head(&fs->wait);
1072 
1073 	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1074 	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1075 	st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1076 
1077 	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1078 		printk(KERN_ERR "fd%d: couldn't request irq %d for %s\n",
1079 		       index, fs->swim3_intr, swim->full_name);
1080 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1081 		goto out_unmap;
1082 		return -EBUSY;
1083 	}
1084 /*
1085 	if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1086 		printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1087 		       fs->dma_intr);
1088 		return -EBUSY;
1089 	}
1090 */
1091 
1092 	init_timer(&fs->timeout);
1093 
1094 	printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1095 		mediabay ? "in media bay" : "");
1096 
1097 	return 0;
1098 
1099  out_unmap:
1100 	iounmap(fs->dma);
1101 	iounmap(fs->swim3);
1102 
1103  out_release:
1104 	macio_release_resource(mdev, 0);
1105 	macio_release_resource(mdev, 1);
1106 
1107 	return rc;
1108 }
1109 
1110 static int __devinit swim3_attach(struct macio_dev *mdev, const struct of_device_id *match)
1111 {
1112 	int i, rc;
1113 	struct gendisk *disk;
1114 
1115 	/* Add the drive */
1116 	rc = swim3_add_device(mdev, floppy_count);
1117 	if (rc)
1118 		return rc;
1119 
1120 	/* Now create the queue if not there yet */
1121 	if (swim3_queue == NULL) {
1122 		/* If we failed, there isn't much we can do as the driver is still
1123 		 * too dumb to remove the device, just bail out
1124 		 */
1125 		if (register_blkdev(FLOPPY_MAJOR, "fd"))
1126 			return 0;
1127 		swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1128 		if (swim3_queue == NULL) {
1129 			unregister_blkdev(FLOPPY_MAJOR, "fd");
1130 			return 0;
1131 		}
1132 	}
1133 
1134 	/* Now register that disk. Same comment about failure handling */
1135 	i = floppy_count++;
1136 	disk = disks[i] = alloc_disk(1);
1137 	if (disk == NULL)
1138 		return 0;
1139 
1140 	disk->major = FLOPPY_MAJOR;
1141 	disk->first_minor = i;
1142 	disk->fops = &floppy_fops;
1143 	disk->private_data = &floppy_states[i];
1144 	disk->queue = swim3_queue;
1145 	disk->flags |= GENHD_FL_REMOVABLE;
1146 	sprintf(disk->disk_name, "fd%d", i);
1147 	set_capacity(disk, 2880);
1148 	add_disk(disk);
1149 
1150 	return 0;
1151 }
1152 
1153 static struct of_device_id swim3_match[] =
1154 {
1155 	{
1156 	.name		= "swim3",
1157 	},
1158 	{
1159 	.compatible	= "ohare-swim3"
1160 	},
1161 	{
1162 	.compatible	= "swim3"
1163 	},
1164 };
1165 
1166 static struct macio_driver swim3_driver =
1167 {
1168 	.name 		= "swim3",
1169 	.match_table	= swim3_match,
1170 	.probe		= swim3_attach,
1171 #if 0
1172 	.suspend	= swim3_suspend,
1173 	.resume		= swim3_resume,
1174 #endif
1175 };
1176 
1177 
1178 int swim3_init(void)
1179 {
1180 	macio_register_driver(&swim3_driver);
1181 	return 0;
1182 }
1183 
1184 module_init(swim3_init)
1185 
1186 MODULE_LICENSE("GPL");
1187 MODULE_AUTHOR("Paul Mackerras");
1188 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1189