xref: /linux/drivers/block/swim3.c (revision 4bedea94545165364618d403d03b61d797acba0b)
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/config.h>
20 #include <linux/stddef.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/timer.h>
24 #include <linux/delay.h>
25 #include <linux/fd.h>
26 #include <linux/ioctl.h>
27 #include <linux/blkdev.h>
28 #include <linux/devfs_fs_kernel.h>
29 #include <linux/interrupt.h>
30 #include <linux/module.h>
31 #include <asm/io.h>
32 #include <asm/dbdma.h>
33 #include <asm/prom.h>
34 #include <asm/uaccess.h>
35 #include <asm/mediabay.h>
36 #include <asm/machdep.h>
37 #include <asm/pmac_feature.h>
38 
39 static struct request_queue *swim3_queue;
40 static struct gendisk *disks[2];
41 static struct request *fd_req;
42 
43 #define MAX_FLOPPIES	2
44 
45 enum swim_state {
46 	idle,
47 	locating,
48 	seeking,
49 	settling,
50 	do_transfer,
51 	jogging,
52 	available,
53 	revalidating,
54 	ejecting
55 };
56 
57 #define REG(x)	unsigned char x; char x ## _pad[15];
58 
59 /*
60  * The names for these registers mostly represent speculation on my part.
61  * It will be interesting to see how close they are to the names Apple uses.
62  */
63 struct swim3 {
64 	REG(data);
65 	REG(timer);		/* counts down at 1MHz */
66 	REG(error);
67 	REG(mode);
68 	REG(select);		/* controls CA0, CA1, CA2 and LSTRB signals */
69 	REG(setup);
70 	REG(control);		/* writing bits clears them */
71 	REG(status);		/* writing bits sets them in control */
72 	REG(intr);
73 	REG(nseek);		/* # tracks to seek */
74 	REG(ctrack);		/* current track number */
75 	REG(csect);		/* current sector number */
76 	REG(gap3);		/* size of gap 3 in track format */
77 	REG(sector);		/* sector # to read or write */
78 	REG(nsect);		/* # sectors to read or write */
79 	REG(intr_enable);
80 };
81 
82 #define control_bic	control
83 #define control_bis	status
84 
85 /* Bits in select register */
86 #define CA_MASK		7
87 #define LSTRB		8
88 
89 /* Bits in control register */
90 #define DO_SEEK		0x80
91 #define FORMAT		0x40
92 #define SELECT		0x20
93 #define WRITE_SECTORS	0x10
94 #define DO_ACTION	0x08
95 #define DRIVE2_ENABLE	0x04
96 #define DRIVE_ENABLE	0x02
97 #define INTR_ENABLE	0x01
98 
99 /* Bits in status register */
100 #define FIFO_1BYTE	0x80
101 #define FIFO_2BYTE	0x40
102 #define ERROR		0x20
103 #define DATA		0x08
104 #define RDDATA		0x04
105 #define INTR_PENDING	0x02
106 #define MARK_BYTE	0x01
107 
108 /* Bits in intr and intr_enable registers */
109 #define ERROR_INTR	0x20
110 #define DATA_CHANGED	0x10
111 #define TRANSFER_DONE	0x08
112 #define SEEN_SECTOR	0x04
113 #define SEEK_DONE	0x02
114 #define TIMER_DONE	0x01
115 
116 /* Bits in error register */
117 #define ERR_DATA_CRC	0x80
118 #define ERR_ADDR_CRC	0x40
119 #define ERR_OVERRUN	0x04
120 #define ERR_UNDERRUN	0x01
121 
122 /* Bits in setup register */
123 #define S_SW_RESET	0x80
124 #define S_GCR_WRITE	0x40
125 #define S_IBM_DRIVE	0x20
126 #define S_TEST_MODE	0x10
127 #define S_FCLK_DIV2	0x08
128 #define S_GCR		0x04
129 #define S_COPY_PROT	0x02
130 #define S_INV_WDATA	0x01
131 
132 /* Select values for swim3_action */
133 #define SEEK_POSITIVE	0
134 #define SEEK_NEGATIVE	4
135 #define STEP		1
136 #define MOTOR_ON	2
137 #define MOTOR_OFF	6
138 #define INDEX		3
139 #define EJECT		7
140 #define SETMFM		9
141 #define SETGCR		13
142 
143 /* Select values for swim3_select and swim3_readbit */
144 #define STEP_DIR	0
145 #define STEPPING	1
146 #define MOTOR_ON	2
147 #define RELAX		3	/* also eject in progress */
148 #define READ_DATA_0	4
149 #define TWOMEG_DRIVE	5
150 #define SINGLE_SIDED	6	/* drive or diskette is 4MB type? */
151 #define DRIVE_PRESENT	7
152 #define DISK_IN		8
153 #define WRITE_PROT	9
154 #define TRACK_ZERO	10
155 #define TACHO		11
156 #define READ_DATA_1	12
157 #define MFM_MODE	13
158 #define SEEK_COMPLETE	14
159 #define ONEMEG_MEDIA	15
160 
161 /* Definitions of values used in writing and formatting */
162 #define DATA_ESCAPE	0x99
163 #define GCR_SYNC_EXC	0x3f
164 #define GCR_SYNC_CONV	0x80
165 #define GCR_FIRST_MARK	0xd5
166 #define GCR_SECOND_MARK	0xaa
167 #define GCR_ADDR_MARK	"\xd5\xaa\x00"
168 #define GCR_DATA_MARK	"\xd5\xaa\x0b"
169 #define GCR_SLIP_BYTE	"\x27\xaa"
170 #define GCR_SELF_SYNC	"\x3f\xbf\x1e\x34\x3c\x3f"
171 
172 #define DATA_99		"\x99\x99"
173 #define MFM_ADDR_MARK	"\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
174 #define MFM_INDEX_MARK	"\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
175 #define MFM_GAP_LEN	12
176 
177 struct floppy_state {
178 	enum swim_state	state;
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(request_queue_t * 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, struct pt_regs *regs);
242 /*static void fd_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs);*/
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 static int swim3_add_device(struct device_node *swims);
254 int swim3_init(void);
255 
256 #ifndef CONFIG_PMAC_PBOOK
257 #define check_media_bay(which, what)	1
258 #endif
259 
260 static void swim3_select(struct floppy_state *fs, int sel)
261 {
262 	struct swim3 __iomem *sw = fs->swim3;
263 
264 	out_8(&sw->select, RELAX);
265 	if (sel & 8)
266 		out_8(&sw->control_bis, SELECT);
267 	else
268 		out_8(&sw->control_bic, SELECT);
269 	out_8(&sw->select, sel & CA_MASK);
270 }
271 
272 static void swim3_action(struct floppy_state *fs, int action)
273 {
274 	struct swim3 __iomem *sw = fs->swim3;
275 
276 	swim3_select(fs, action);
277 	udelay(1);
278 	out_8(&sw->select, sw->select | LSTRB);
279 	udelay(2);
280 	out_8(&sw->select, sw->select & ~LSTRB);
281 	udelay(1);
282 }
283 
284 static int swim3_readbit(struct floppy_state *fs, int bit)
285 {
286 	struct swim3 __iomem *sw = fs->swim3;
287 	int stat;
288 
289 	swim3_select(fs, bit);
290 	udelay(1);
291 	stat = in_8(&sw->status);
292 	return (stat & DATA) == 0;
293 }
294 
295 static void do_fd_request(request_queue_t * q)
296 {
297 	int i;
298 	for(i=0;i<floppy_count;i++)
299 	{
300 		if (floppy_states[i].media_bay &&
301 			check_media_bay(floppy_states[i].media_bay, MB_FD))
302 			continue;
303 		start_request(&floppy_states[i]);
304 	}
305 	sti();
306 }
307 
308 static void start_request(struct floppy_state *fs)
309 {
310 	struct request *req;
311 	unsigned long x;
312 
313 	if (fs->state == idle && fs->wanted) {
314 		fs->state = available;
315 		wake_up(&fs->wait);
316 		return;
317 	}
318 	while (fs->state == idle && (req = elv_next_request(swim3_queue))) {
319 #if 0
320 		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
321 		       req->rq_disk->disk_name, req->cmd,
322 		       (long)req->sector, req->nr_sectors, req->buffer);
323 		printk("           rq_status=%d errors=%d current_nr_sectors=%ld\n",
324 		       req->rq_status, req->errors, req->current_nr_sectors);
325 #endif
326 
327 		if (req->sector < 0 || req->sector >= fs->total_secs) {
328 			end_request(req, 0);
329 			continue;
330 		}
331 		if (req->current_nr_sectors == 0) {
332 			end_request(req, 1);
333 			continue;
334 		}
335 		if (fs->ejected) {
336 			end_request(req, 0);
337 			continue;
338 		}
339 
340 		if (rq_data_dir(req) == WRITE) {
341 			if (fs->write_prot < 0)
342 				fs->write_prot = swim3_readbit(fs, WRITE_PROT);
343 			if (fs->write_prot) {
344 				end_request(req, 0);
345 				continue;
346 			}
347 		}
348 
349 		/* Do not remove the cast. req->sector is now a sector_t and
350 		 * can be 64 bits, but it will never go past 32 bits for this
351 		 * driver anyway, so we can safely cast it down and not have
352 		 * to do a 64/32 division
353 		 */
354 		fs->req_cyl = ((long)req->sector) / fs->secpercyl;
355 		x = ((long)req->sector) % fs->secpercyl;
356 		fs->head = x / fs->secpertrack;
357 		fs->req_sector = x % fs->secpertrack + 1;
358 		fd_req = req;
359 		fs->state = do_transfer;
360 		fs->retries = 0;
361 
362 		act(fs);
363 	}
364 }
365 
366 static void set_timeout(struct floppy_state *fs, int nticks,
367 			void (*proc)(unsigned long))
368 {
369 	unsigned long flags;
370 
371 	save_flags(flags); cli();
372 	if (fs->timeout_pending)
373 		del_timer(&fs->timeout);
374 	fs->timeout.expires = jiffies + nticks;
375 	fs->timeout.function = proc;
376 	fs->timeout.data = (unsigned long) fs;
377 	add_timer(&fs->timeout);
378 	fs->timeout_pending = 1;
379 	restore_flags(flags);
380 }
381 
382 static inline void scan_track(struct floppy_state *fs)
383 {
384 	struct swim3 __iomem *sw = fs->swim3;
385 
386 	swim3_select(fs, READ_DATA_0);
387 	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
388 	in_8(&sw->error);
389 	out_8(&sw->intr_enable, SEEN_SECTOR);
390 	out_8(&sw->control_bis, DO_ACTION);
391 	/* enable intr when track found */
392 	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
393 }
394 
395 static inline void seek_track(struct floppy_state *fs, int n)
396 {
397 	struct swim3 __iomem *sw = fs->swim3;
398 
399 	if (n >= 0) {
400 		swim3_action(fs, SEEK_POSITIVE);
401 		sw->nseek = n;
402 	} else {
403 		swim3_action(fs, SEEK_NEGATIVE);
404 		sw->nseek = -n;
405 	}
406 	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
407 	swim3_select(fs, STEP);
408 	in_8(&sw->error);
409 	/* enable intr when seek finished */
410 	out_8(&sw->intr_enable, SEEK_DONE);
411 	out_8(&sw->control_bis, DO_SEEK);
412 	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
413 	fs->settle_time = 0;
414 }
415 
416 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
417 			    void *buf, int count)
418 {
419 	st_le16(&cp->req_count, count);
420 	st_le16(&cp->command, cmd);
421 	st_le32(&cp->phy_addr, virt_to_bus(buf));
422 	cp->xfer_status = 0;
423 }
424 
425 static inline void setup_transfer(struct floppy_state *fs)
426 {
427 	int n;
428 	struct swim3 __iomem *sw = fs->swim3;
429 	struct dbdma_cmd *cp = fs->dma_cmd;
430 	struct dbdma_regs __iomem *dr = fs->dma;
431 
432 	if (fd_req->current_nr_sectors <= 0) {
433 		printk(KERN_ERR "swim3: transfer 0 sectors?\n");
434 		return;
435 	}
436 	if (rq_data_dir(fd_req) == WRITE)
437 		n = 1;
438 	else {
439 		n = fs->secpertrack - fs->req_sector + 1;
440 		if (n > fd_req->current_nr_sectors)
441 			n = fd_req->current_nr_sectors;
442 	}
443 	fs->scount = n;
444 	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
445 	out_8(&sw->sector, fs->req_sector);
446 	out_8(&sw->nsect, n);
447 	out_8(&sw->gap3, 0);
448 	out_le32(&dr->cmdptr, virt_to_bus(cp));
449 	if (rq_data_dir(fd_req) == WRITE) {
450 		/* Set up 3 dma commands: write preamble, data, postamble */
451 		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
452 		++cp;
453 		init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
454 		++cp;
455 		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
456 	} else {
457 		init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
458 	}
459 	++cp;
460 	out_le16(&cp->command, DBDMA_STOP);
461 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
462 	in_8(&sw->error);
463 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
464 	if (rq_data_dir(fd_req) == WRITE)
465 		out_8(&sw->control_bis, WRITE_SECTORS);
466 	in_8(&sw->intr);
467 	out_le32(&dr->control, (RUN << 16) | RUN);
468 	/* enable intr when transfer complete */
469 	out_8(&sw->intr_enable, TRANSFER_DONE);
470 	out_8(&sw->control_bis, DO_ACTION);
471 	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
472 }
473 
474 static void act(struct floppy_state *fs)
475 {
476 	for (;;) {
477 		switch (fs->state) {
478 		case idle:
479 			return;		/* XXX shouldn't get here */
480 
481 		case locating:
482 			if (swim3_readbit(fs, TRACK_ZERO)) {
483 				fs->cur_cyl = 0;
484 				if (fs->req_cyl == 0)
485 					fs->state = do_transfer;
486 				else
487 					fs->state = seeking;
488 				break;
489 			}
490 			scan_track(fs);
491 			return;
492 
493 		case seeking:
494 			if (fs->cur_cyl < 0) {
495 				fs->expect_cyl = -1;
496 				fs->state = locating;
497 				break;
498 			}
499 			if (fs->req_cyl == fs->cur_cyl) {
500 				printk("whoops, seeking 0\n");
501 				fs->state = do_transfer;
502 				break;
503 			}
504 			seek_track(fs, fs->req_cyl - fs->cur_cyl);
505 			return;
506 
507 		case settling:
508 			/* check for SEEK_COMPLETE after 30ms */
509 			fs->settle_time = (HZ + 32) / 33;
510 			set_timeout(fs, fs->settle_time, settle_timeout);
511 			return;
512 
513 		case do_transfer:
514 			if (fs->cur_cyl != fs->req_cyl) {
515 				if (fs->retries > 5) {
516 					end_request(fd_req, 0);
517 					fs->state = idle;
518 					return;
519 				}
520 				fs->state = seeking;
521 				break;
522 			}
523 			setup_transfer(fs);
524 			return;
525 
526 		case jogging:
527 			seek_track(fs, -5);
528 			return;
529 
530 		default:
531 			printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
532 			return;
533 		}
534 	}
535 }
536 
537 static void scan_timeout(unsigned long data)
538 {
539 	struct floppy_state *fs = (struct floppy_state *) data;
540 	struct swim3 __iomem *sw = fs->swim3;
541 
542 	fs->timeout_pending = 0;
543 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
544 	out_8(&sw->select, RELAX);
545 	out_8(&sw->intr_enable, 0);
546 	fs->cur_cyl = -1;
547 	if (fs->retries > 5) {
548 		end_request(fd_req, 0);
549 		fs->state = idle;
550 		start_request(fs);
551 	} else {
552 		fs->state = jogging;
553 		act(fs);
554 	}
555 }
556 
557 static void seek_timeout(unsigned long data)
558 {
559 	struct floppy_state *fs = (struct floppy_state *) data;
560 	struct swim3 __iomem *sw = fs->swim3;
561 
562 	fs->timeout_pending = 0;
563 	out_8(&sw->control_bic, DO_SEEK);
564 	out_8(&sw->select, RELAX);
565 	out_8(&sw->intr_enable, 0);
566 	printk(KERN_ERR "swim3: seek timeout\n");
567 	end_request(fd_req, 0);
568 	fs->state = idle;
569 	start_request(fs);
570 }
571 
572 static void settle_timeout(unsigned long data)
573 {
574 	struct floppy_state *fs = (struct floppy_state *) data;
575 	struct swim3 __iomem *sw = fs->swim3;
576 
577 	fs->timeout_pending = 0;
578 	if (swim3_readbit(fs, SEEK_COMPLETE)) {
579 		out_8(&sw->select, RELAX);
580 		fs->state = locating;
581 		act(fs);
582 		return;
583 	}
584 	out_8(&sw->select, RELAX);
585 	if (fs->settle_time < 2*HZ) {
586 		++fs->settle_time;
587 		set_timeout(fs, 1, settle_timeout);
588 		return;
589 	}
590 	printk(KERN_ERR "swim3: seek settle timeout\n");
591 	end_request(fd_req, 0);
592 	fs->state = idle;
593 	start_request(fs);
594 }
595 
596 static void xfer_timeout(unsigned long data)
597 {
598 	struct floppy_state *fs = (struct floppy_state *) data;
599 	struct swim3 __iomem *sw = fs->swim3;
600 	struct dbdma_regs __iomem *dr = fs->dma;
601 	struct dbdma_cmd *cp = fs->dma_cmd;
602 	unsigned long s;
603 	int n;
604 
605 	fs->timeout_pending = 0;
606 	out_le32(&dr->control, RUN << 16);
607 	/* We must wait a bit for dbdma to stop */
608 	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
609 		udelay(1);
610 	out_8(&sw->intr_enable, 0);
611 	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
612 	out_8(&sw->select, RELAX);
613 	if (rq_data_dir(fd_req) == WRITE)
614 		++cp;
615 	if (ld_le16(&cp->xfer_status) != 0)
616 		s = fs->scount - ((ld_le16(&cp->res_count) + 511) >> 9);
617 	else
618 		s = 0;
619 	fd_req->sector += s;
620 	fd_req->current_nr_sectors -= s;
621 	printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
622 	       (rq_data_dir(fd_req)==WRITE? "writ": "read"), (long)fd_req->sector);
623 	end_request(fd_req, 0);
624 	fs->state = idle;
625 	start_request(fs);
626 }
627 
628 static irqreturn_t swim3_interrupt(int irq, void *dev_id, struct pt_regs *regs)
629 {
630 	struct floppy_state *fs = (struct floppy_state *) dev_id;
631 	struct swim3 __iomem *sw = fs->swim3;
632 	int intr, err, n;
633 	int stat, resid;
634 	struct dbdma_regs __iomem *dr;
635 	struct dbdma_cmd *cp;
636 
637 	intr = in_8(&sw->intr);
638 	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
639 	if ((intr & ERROR_INTR) && fs->state != do_transfer)
640 		printk(KERN_ERR "swim3_interrupt, state=%d, dir=%lx, intr=%x, err=%x\n",
641 		       fs->state, rq_data_dir(fd_req), intr, err);
642 	switch (fs->state) {
643 	case locating:
644 		if (intr & SEEN_SECTOR) {
645 			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
646 			out_8(&sw->select, RELAX);
647 			out_8(&sw->intr_enable, 0);
648 			del_timer(&fs->timeout);
649 			fs->timeout_pending = 0;
650 			if (sw->ctrack == 0xff) {
651 				printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
652 				fs->cur_cyl = -1;
653 				if (fs->retries > 5) {
654 					end_request(fd_req, 0);
655 					fs->state = idle;
656 					start_request(fs);
657 				} else {
658 					fs->state = jogging;
659 					act(fs);
660 				}
661 				break;
662 			}
663 			fs->cur_cyl = sw->ctrack;
664 			fs->cur_sector = sw->csect;
665 			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
666 				printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
667 				       fs->expect_cyl, fs->cur_cyl);
668 			fs->state = do_transfer;
669 			act(fs);
670 		}
671 		break;
672 	case seeking:
673 	case jogging:
674 		if (sw->nseek == 0) {
675 			out_8(&sw->control_bic, DO_SEEK);
676 			out_8(&sw->select, RELAX);
677 			out_8(&sw->intr_enable, 0);
678 			del_timer(&fs->timeout);
679 			fs->timeout_pending = 0;
680 			if (fs->state == seeking)
681 				++fs->retries;
682 			fs->state = settling;
683 			act(fs);
684 		}
685 		break;
686 	case settling:
687 		out_8(&sw->intr_enable, 0);
688 		del_timer(&fs->timeout);
689 		fs->timeout_pending = 0;
690 		act(fs);
691 		break;
692 	case do_transfer:
693 		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
694 			break;
695 		out_8(&sw->intr_enable, 0);
696 		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
697 		out_8(&sw->select, RELAX);
698 		del_timer(&fs->timeout);
699 		fs->timeout_pending = 0;
700 		dr = fs->dma;
701 		cp = fs->dma_cmd;
702 		if (rq_data_dir(fd_req) == WRITE)
703 			++cp;
704 		/*
705 		 * Check that the main data transfer has finished.
706 		 * On writing, the swim3 sometimes doesn't use
707 		 * up all the bytes of the postamble, so we can still
708 		 * see DMA active here.  That doesn't matter as long
709 		 * as all the sector data has been transferred.
710 		 */
711 		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
712 			/* wait a little while for DMA to complete */
713 			for (n = 0; n < 100; ++n) {
714 				if (cp->xfer_status != 0)
715 					break;
716 				udelay(1);
717 				barrier();
718 			}
719 		}
720 		/* turn off DMA */
721 		out_le32(&dr->control, (RUN | PAUSE) << 16);
722 		stat = ld_le16(&cp->xfer_status);
723 		resid = ld_le16(&cp->res_count);
724 		if (intr & ERROR_INTR) {
725 			n = fs->scount - 1 - resid / 512;
726 			if (n > 0) {
727 				fd_req->sector += n;
728 				fd_req->current_nr_sectors -= n;
729 				fd_req->buffer += n * 512;
730 				fs->req_sector += n;
731 			}
732 			if (fs->retries < 5) {
733 				++fs->retries;
734 				act(fs);
735 			} else {
736 				printk("swim3: error %sing block %ld (err=%x)\n",
737 				       rq_data_dir(fd_req) == WRITE? "writ": "read",
738 				       (long)fd_req->sector, err);
739 				end_request(fd_req, 0);
740 				fs->state = idle;
741 			}
742 		} else {
743 			if ((stat & ACTIVE) == 0 || resid != 0) {
744 				/* musta been an error */
745 				printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
746 				printk(KERN_ERR "  state=%d, dir=%lx, intr=%x, err=%x\n",
747 				       fs->state, rq_data_dir(fd_req), intr, err);
748 				end_request(fd_req, 0);
749 				fs->state = idle;
750 				start_request(fs);
751 				break;
752 			}
753 			fd_req->sector += fs->scount;
754 			fd_req->current_nr_sectors -= fs->scount;
755 			fd_req->buffer += fs->scount * 512;
756 			if (fd_req->current_nr_sectors <= 0) {
757 				end_request(fd_req, 1);
758 				fs->state = idle;
759 			} else {
760 				fs->req_sector += fs->scount;
761 				if (fs->req_sector > fs->secpertrack) {
762 					fs->req_sector -= fs->secpertrack;
763 					if (++fs->head > 1) {
764 						fs->head = 0;
765 						++fs->req_cyl;
766 					}
767 				}
768 				act(fs);
769 			}
770 		}
771 		if (fs->state == idle)
772 			start_request(fs);
773 		break;
774 	default:
775 		printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
776 	}
777 	return IRQ_HANDLED;
778 }
779 
780 /*
781 static void fd_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
782 {
783 }
784 */
785 
786 static int grab_drive(struct floppy_state *fs, enum swim_state state,
787 		      int interruptible)
788 {
789 	unsigned long flags;
790 
791 	save_flags(flags);
792 	cli();
793 	if (fs->state != idle) {
794 		++fs->wanted;
795 		while (fs->state != available) {
796 			if (interruptible && signal_pending(current)) {
797 				--fs->wanted;
798 				restore_flags(flags);
799 				return -EINTR;
800 			}
801 			interruptible_sleep_on(&fs->wait);
802 		}
803 		--fs->wanted;
804 	}
805 	fs->state = state;
806 	restore_flags(flags);
807 	return 0;
808 }
809 
810 static void release_drive(struct floppy_state *fs)
811 {
812 	unsigned long flags;
813 
814 	save_flags(flags);
815 	cli();
816 	fs->state = idle;
817 	start_request(fs);
818 	restore_flags(flags);
819 }
820 
821 static int fd_eject(struct floppy_state *fs)
822 {
823 	int err, n;
824 
825 	err = grab_drive(fs, ejecting, 1);
826 	if (err)
827 		return err;
828 	swim3_action(fs, EJECT);
829 	for (n = 20; n > 0; --n) {
830 		if (signal_pending(current)) {
831 			err = -EINTR;
832 			break;
833 		}
834 		swim3_select(fs, RELAX);
835 		current->state = TASK_INTERRUPTIBLE;
836 		schedule_timeout(1);
837 		if (swim3_readbit(fs, DISK_IN) == 0)
838 			break;
839 	}
840 	swim3_select(fs, RELAX);
841 	udelay(150);
842 	fs->ejected = 1;
843 	release_drive(fs);
844 	return err;
845 }
846 
847 static struct floppy_struct floppy_type =
848 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
849 
850 static int floppy_ioctl(struct inode *inode, struct file *filp,
851 			unsigned int cmd, unsigned long param)
852 {
853 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
854 	int err;
855 
856 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
857 		return -EPERM;
858 
859 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
860 		return -ENXIO;
861 
862 	switch (cmd) {
863 	case FDEJECT:
864 		if (fs->ref_count != 1)
865 			return -EBUSY;
866 		err = fd_eject(fs);
867 		return err;
868 	case FDGETPRM:
869 	        if (copy_to_user((void __user *) param, &floppy_type,
870 				 sizeof(struct floppy_struct)))
871 			return -EFAULT;
872 		return 0;
873 	}
874 	return -ENOTTY;
875 }
876 
877 static int floppy_open(struct inode *inode, struct file *filp)
878 {
879 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
880 	struct swim3 __iomem *sw = fs->swim3;
881 	int n, err = 0;
882 
883 	if (fs->ref_count == 0) {
884 		if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
885 			return -ENXIO;
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 			current->state = TASK_INTERRUPTIBLE;
904 			schedule_timeout(1);
905 		}
906 		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
907 				 || swim3_readbit(fs, DISK_IN) == 0))
908 			err = -ENXIO;
909 		swim3_action(fs, SETMFM);
910 		swim3_select(fs, RELAX);
911 
912 	} else if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
913 		return -EBUSY;
914 
915 	if (err == 0 && (filp->f_flags & O_NDELAY) == 0
916 	    && (filp->f_mode & 3)) {
917 		check_disk_change(inode->i_bdev);
918 		if (fs->ejected)
919 			err = -ENXIO;
920 	}
921 
922 	if (err == 0 && (filp->f_mode & 2)) {
923 		if (fs->write_prot < 0)
924 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
925 		if (fs->write_prot)
926 			err = -EROFS;
927 	}
928 
929 	if (err) {
930 		if (fs->ref_count == 0) {
931 			swim3_action(fs, MOTOR_OFF);
932 			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
933 			swim3_select(fs, RELAX);
934 		}
935 		return err;
936 	}
937 
938 	if (filp->f_flags & O_EXCL)
939 		fs->ref_count = -1;
940 	else
941 		++fs->ref_count;
942 
943 	return 0;
944 }
945 
946 static int floppy_release(struct inode *inode, struct file *filp)
947 {
948 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
949 	struct swim3 __iomem *sw = fs->swim3;
950 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
951 		swim3_action(fs, MOTOR_OFF);
952 		out_8(&sw->control_bic, 0xff);
953 		swim3_select(fs, RELAX);
954 	}
955 	return 0;
956 }
957 
958 static int floppy_check_change(struct gendisk *disk)
959 {
960 	struct floppy_state *fs = disk->private_data;
961 	return fs->ejected;
962 }
963 
964 static int floppy_revalidate(struct gendisk *disk)
965 {
966 	struct floppy_state *fs = disk->private_data;
967 	struct swim3 __iomem *sw;
968 	int ret, n;
969 
970 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
971 		return -ENXIO;
972 
973 	sw = fs->swim3;
974 	grab_drive(fs, revalidating, 0);
975 	out_8(&sw->intr_enable, 0);
976 	out_8(&sw->control_bis, DRIVE_ENABLE);
977 	swim3_action(fs, MOTOR_ON);	/* necessary? */
978 	fs->write_prot = -1;
979 	fs->cur_cyl = -1;
980 	mdelay(1);
981 	for (n = HZ; n > 0; --n) {
982 		if (swim3_readbit(fs, SEEK_COMPLETE))
983 			break;
984 		if (signal_pending(current))
985 			break;
986 		swim3_select(fs, RELAX);
987 		current->state = TASK_INTERRUPTIBLE;
988 		schedule_timeout(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 int swim3_init(void)
1013 {
1014 	struct device_node *swim;
1015 	int err = -ENOMEM;
1016 	int i;
1017 
1018 	devfs_mk_dir("floppy");
1019 
1020 	swim = find_devices("floppy");
1021 	while (swim && (floppy_count < MAX_FLOPPIES))
1022 	{
1023 		swim3_add_device(swim);
1024 		swim = swim->next;
1025 	}
1026 
1027 	swim = find_devices("swim3");
1028 	while (swim && (floppy_count < MAX_FLOPPIES))
1029 	{
1030 		swim3_add_device(swim);
1031 		swim = swim->next;
1032 	}
1033 
1034 	if (!floppy_count)
1035 		return -ENODEV;
1036 
1037 	for (i = 0; i < floppy_count; i++) {
1038 		disks[i] = alloc_disk(1);
1039 		if (!disks[i])
1040 			goto out;
1041 	}
1042 
1043 	if (register_blkdev(FLOPPY_MAJOR, "fd")) {
1044 		err = -EBUSY;
1045 		goto out;
1046 	}
1047 
1048 	swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1049 	if (!swim3_queue) {
1050 		err = -ENOMEM;
1051 		goto out_queue;
1052 	}
1053 
1054 	for (i = 0; i < floppy_count; i++) {
1055 		struct gendisk *disk = disks[i];
1056 		disk->major = FLOPPY_MAJOR;
1057 		disk->first_minor = i;
1058 		disk->fops = &floppy_fops;
1059 		disk->private_data = &floppy_states[i];
1060 		disk->queue = swim3_queue;
1061 		disk->flags |= GENHD_FL_REMOVABLE;
1062 		sprintf(disk->disk_name, "fd%d", i);
1063 		sprintf(disk->devfs_name, "floppy/%d", i);
1064 		set_capacity(disk, 2880);
1065 		add_disk(disk);
1066 	}
1067 	return 0;
1068 
1069 out_queue:
1070 	unregister_blkdev(FLOPPY_MAJOR, "fd");
1071 out:
1072 	while (i--)
1073 		put_disk(disks[i]);
1074 	/* shouldn't we do something with results of swim_add_device()? */
1075 	return err;
1076 }
1077 
1078 static int swim3_add_device(struct device_node *swim)
1079 {
1080 	struct device_node *mediabay;
1081 	struct floppy_state *fs = &floppy_states[floppy_count];
1082 
1083 	if (swim->n_addrs < 2)
1084 	{
1085 		printk(KERN_INFO "swim3: expecting 2 addrs (n_addrs:%d, n_intrs:%d)\n",
1086 		       swim->n_addrs, swim->n_intrs);
1087 		return -EINVAL;
1088 	}
1089 
1090 	if (swim->n_intrs < 2)
1091 	{
1092 		printk(KERN_INFO "swim3: expecting 2 intrs (n_addrs:%d, n_intrs:%d)\n",
1093 		       swim->n_addrs, swim->n_intrs);
1094 		return -EINVAL;
1095 	}
1096 
1097 	if (!request_OF_resource(swim, 0, NULL)) {
1098 		printk(KERN_INFO "swim3: can't request IO resource !\n");
1099 		return -EINVAL;
1100 	}
1101 
1102 	mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ? swim->parent : NULL;
1103 	if (mediabay == NULL)
1104 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1105 
1106 	memset(fs, 0, sizeof(*fs));
1107 	fs->state = idle;
1108 	fs->swim3 = (struct swim3 __iomem *)
1109 		ioremap(swim->addrs[0].address, 0x200);
1110 	fs->dma = (struct dbdma_regs __iomem *)
1111 		ioremap(swim->addrs[1].address, 0x200);
1112 	fs->swim3_intr = swim->intrs[0].line;
1113 	fs->dma_intr = swim->intrs[1].line;
1114 	fs->cur_cyl = -1;
1115 	fs->cur_sector = -1;
1116 	fs->secpercyl = 36;
1117 	fs->secpertrack = 18;
1118 	fs->total_secs = 2880;
1119 	fs->media_bay = mediabay;
1120 	init_waitqueue_head(&fs->wait);
1121 
1122 	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1123 	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1124 	st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1125 
1126 	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1127 		printk(KERN_ERR "Couldn't get irq %d for SWIM3\n", fs->swim3_intr);
1128 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1129 		return -EBUSY;
1130 	}
1131 /*
1132 	if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1133 		printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1134 		       fs->dma_intr);
1135 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1136 		return -EBUSY;
1137 	}
1138 */
1139 
1140 	init_timer(&fs->timeout);
1141 
1142 	printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1143 		mediabay ? "in media bay" : "");
1144 
1145 	floppy_count++;
1146 
1147 	return 0;
1148 }
1149 
1150 module_init(swim3_init)
1151 
1152 MODULE_LICENSE("GPL");
1153 MODULE_AUTHOR("Paul Mackerras");
1154 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1155