xref: /openbmc/linux/drivers/block/swim3.c (revision 27ac801a2e513708e2da648722326349514976d5)
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_MEDIABAY
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 #ifdef CONFIG_PMAC_MEDIABAY
301 		if (floppy_states[i].media_bay &&
302 			check_media_bay(floppy_states[i].media_bay, MB_FD))
303 			continue;
304 #endif /* CONFIG_PMAC_MEDIABAY */
305 		start_request(&floppy_states[i]);
306 	}
307 	sti();
308 }
309 
310 static void start_request(struct floppy_state *fs)
311 {
312 	struct request *req;
313 	unsigned long x;
314 
315 	if (fs->state == idle && fs->wanted) {
316 		fs->state = available;
317 		wake_up(&fs->wait);
318 		return;
319 	}
320 	while (fs->state == idle && (req = elv_next_request(swim3_queue))) {
321 #if 0
322 		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
323 		       req->rq_disk->disk_name, req->cmd,
324 		       (long)req->sector, req->nr_sectors, req->buffer);
325 		printk("           rq_status=%d errors=%d current_nr_sectors=%ld\n",
326 		       req->rq_status, req->errors, req->current_nr_sectors);
327 #endif
328 
329 		if (req->sector < 0 || req->sector >= fs->total_secs) {
330 			end_request(req, 0);
331 			continue;
332 		}
333 		if (req->current_nr_sectors == 0) {
334 			end_request(req, 1);
335 			continue;
336 		}
337 		if (fs->ejected) {
338 			end_request(req, 0);
339 			continue;
340 		}
341 
342 		if (rq_data_dir(req) == WRITE) {
343 			if (fs->write_prot < 0)
344 				fs->write_prot = swim3_readbit(fs, WRITE_PROT);
345 			if (fs->write_prot) {
346 				end_request(req, 0);
347 				continue;
348 			}
349 		}
350 
351 		/* Do not remove the cast. req->sector is now a sector_t and
352 		 * can be 64 bits, but it will never go past 32 bits for this
353 		 * driver anyway, so we can safely cast it down and not have
354 		 * to do a 64/32 division
355 		 */
356 		fs->req_cyl = ((long)req->sector) / fs->secpercyl;
357 		x = ((long)req->sector) % fs->secpercyl;
358 		fs->head = x / fs->secpertrack;
359 		fs->req_sector = x % fs->secpertrack + 1;
360 		fd_req = req;
361 		fs->state = do_transfer;
362 		fs->retries = 0;
363 
364 		act(fs);
365 	}
366 }
367 
368 static void set_timeout(struct floppy_state *fs, int nticks,
369 			void (*proc)(unsigned long))
370 {
371 	unsigned long flags;
372 
373 	save_flags(flags); cli();
374 	if (fs->timeout_pending)
375 		del_timer(&fs->timeout);
376 	fs->timeout.expires = jiffies + nticks;
377 	fs->timeout.function = proc;
378 	fs->timeout.data = (unsigned long) fs;
379 	add_timer(&fs->timeout);
380 	fs->timeout_pending = 1;
381 	restore_flags(flags);
382 }
383 
384 static inline void scan_track(struct floppy_state *fs)
385 {
386 	struct swim3 __iomem *sw = fs->swim3;
387 
388 	swim3_select(fs, READ_DATA_0);
389 	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
390 	in_8(&sw->error);
391 	out_8(&sw->intr_enable, SEEN_SECTOR);
392 	out_8(&sw->control_bis, DO_ACTION);
393 	/* enable intr when track found */
394 	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
395 }
396 
397 static inline void seek_track(struct floppy_state *fs, int n)
398 {
399 	struct swim3 __iomem *sw = fs->swim3;
400 
401 	if (n >= 0) {
402 		swim3_action(fs, SEEK_POSITIVE);
403 		sw->nseek = n;
404 	} else {
405 		swim3_action(fs, SEEK_NEGATIVE);
406 		sw->nseek = -n;
407 	}
408 	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
409 	swim3_select(fs, STEP);
410 	in_8(&sw->error);
411 	/* enable intr when seek finished */
412 	out_8(&sw->intr_enable, SEEK_DONE);
413 	out_8(&sw->control_bis, DO_SEEK);
414 	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
415 	fs->settle_time = 0;
416 }
417 
418 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
419 			    void *buf, int count)
420 {
421 	st_le16(&cp->req_count, count);
422 	st_le16(&cp->command, cmd);
423 	st_le32(&cp->phy_addr, virt_to_bus(buf));
424 	cp->xfer_status = 0;
425 }
426 
427 static inline void setup_transfer(struct floppy_state *fs)
428 {
429 	int n;
430 	struct swim3 __iomem *sw = fs->swim3;
431 	struct dbdma_cmd *cp = fs->dma_cmd;
432 	struct dbdma_regs __iomem *dr = fs->dma;
433 
434 	if (fd_req->current_nr_sectors <= 0) {
435 		printk(KERN_ERR "swim3: transfer 0 sectors?\n");
436 		return;
437 	}
438 	if (rq_data_dir(fd_req) == WRITE)
439 		n = 1;
440 	else {
441 		n = fs->secpertrack - fs->req_sector + 1;
442 		if (n > fd_req->current_nr_sectors)
443 			n = fd_req->current_nr_sectors;
444 	}
445 	fs->scount = n;
446 	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
447 	out_8(&sw->sector, fs->req_sector);
448 	out_8(&sw->nsect, n);
449 	out_8(&sw->gap3, 0);
450 	out_le32(&dr->cmdptr, virt_to_bus(cp));
451 	if (rq_data_dir(fd_req) == WRITE) {
452 		/* Set up 3 dma commands: write preamble, data, postamble */
453 		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
454 		++cp;
455 		init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
456 		++cp;
457 		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
458 	} else {
459 		init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
460 	}
461 	++cp;
462 	out_le16(&cp->command, DBDMA_STOP);
463 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
464 	in_8(&sw->error);
465 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
466 	if (rq_data_dir(fd_req) == WRITE)
467 		out_8(&sw->control_bis, WRITE_SECTORS);
468 	in_8(&sw->intr);
469 	out_le32(&dr->control, (RUN << 16) | RUN);
470 	/* enable intr when transfer complete */
471 	out_8(&sw->intr_enable, TRANSFER_DONE);
472 	out_8(&sw->control_bis, DO_ACTION);
473 	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
474 }
475 
476 static void act(struct floppy_state *fs)
477 {
478 	for (;;) {
479 		switch (fs->state) {
480 		case idle:
481 			return;		/* XXX shouldn't get here */
482 
483 		case locating:
484 			if (swim3_readbit(fs, TRACK_ZERO)) {
485 				fs->cur_cyl = 0;
486 				if (fs->req_cyl == 0)
487 					fs->state = do_transfer;
488 				else
489 					fs->state = seeking;
490 				break;
491 			}
492 			scan_track(fs);
493 			return;
494 
495 		case seeking:
496 			if (fs->cur_cyl < 0) {
497 				fs->expect_cyl = -1;
498 				fs->state = locating;
499 				break;
500 			}
501 			if (fs->req_cyl == fs->cur_cyl) {
502 				printk("whoops, seeking 0\n");
503 				fs->state = do_transfer;
504 				break;
505 			}
506 			seek_track(fs, fs->req_cyl - fs->cur_cyl);
507 			return;
508 
509 		case settling:
510 			/* check for SEEK_COMPLETE after 30ms */
511 			fs->settle_time = (HZ + 32) / 33;
512 			set_timeout(fs, fs->settle_time, settle_timeout);
513 			return;
514 
515 		case do_transfer:
516 			if (fs->cur_cyl != fs->req_cyl) {
517 				if (fs->retries > 5) {
518 					end_request(fd_req, 0);
519 					fs->state = idle;
520 					return;
521 				}
522 				fs->state = seeking;
523 				break;
524 			}
525 			setup_transfer(fs);
526 			return;
527 
528 		case jogging:
529 			seek_track(fs, -5);
530 			return;
531 
532 		default:
533 			printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
534 			return;
535 		}
536 	}
537 }
538 
539 static void scan_timeout(unsigned long data)
540 {
541 	struct floppy_state *fs = (struct floppy_state *) data;
542 	struct swim3 __iomem *sw = fs->swim3;
543 
544 	fs->timeout_pending = 0;
545 	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
546 	out_8(&sw->select, RELAX);
547 	out_8(&sw->intr_enable, 0);
548 	fs->cur_cyl = -1;
549 	if (fs->retries > 5) {
550 		end_request(fd_req, 0);
551 		fs->state = idle;
552 		start_request(fs);
553 	} else {
554 		fs->state = jogging;
555 		act(fs);
556 	}
557 }
558 
559 static void seek_timeout(unsigned long data)
560 {
561 	struct floppy_state *fs = (struct floppy_state *) data;
562 	struct swim3 __iomem *sw = fs->swim3;
563 
564 	fs->timeout_pending = 0;
565 	out_8(&sw->control_bic, DO_SEEK);
566 	out_8(&sw->select, RELAX);
567 	out_8(&sw->intr_enable, 0);
568 	printk(KERN_ERR "swim3: seek timeout\n");
569 	end_request(fd_req, 0);
570 	fs->state = idle;
571 	start_request(fs);
572 }
573 
574 static void settle_timeout(unsigned long data)
575 {
576 	struct floppy_state *fs = (struct floppy_state *) data;
577 	struct swim3 __iomem *sw = fs->swim3;
578 
579 	fs->timeout_pending = 0;
580 	if (swim3_readbit(fs, SEEK_COMPLETE)) {
581 		out_8(&sw->select, RELAX);
582 		fs->state = locating;
583 		act(fs);
584 		return;
585 	}
586 	out_8(&sw->select, RELAX);
587 	if (fs->settle_time < 2*HZ) {
588 		++fs->settle_time;
589 		set_timeout(fs, 1, settle_timeout);
590 		return;
591 	}
592 	printk(KERN_ERR "swim3: seek settle timeout\n");
593 	end_request(fd_req, 0);
594 	fs->state = idle;
595 	start_request(fs);
596 }
597 
598 static void xfer_timeout(unsigned long data)
599 {
600 	struct floppy_state *fs = (struct floppy_state *) data;
601 	struct swim3 __iomem *sw = fs->swim3;
602 	struct dbdma_regs __iomem *dr = fs->dma;
603 	struct dbdma_cmd *cp = fs->dma_cmd;
604 	unsigned long s;
605 	int n;
606 
607 	fs->timeout_pending = 0;
608 	out_le32(&dr->control, RUN << 16);
609 	/* We must wait a bit for dbdma to stop */
610 	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
611 		udelay(1);
612 	out_8(&sw->intr_enable, 0);
613 	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
614 	out_8(&sw->select, RELAX);
615 	if (rq_data_dir(fd_req) == WRITE)
616 		++cp;
617 	if (ld_le16(&cp->xfer_status) != 0)
618 		s = fs->scount - ((ld_le16(&cp->res_count) + 511) >> 9);
619 	else
620 		s = 0;
621 	fd_req->sector += s;
622 	fd_req->current_nr_sectors -= s;
623 	printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
624 	       (rq_data_dir(fd_req)==WRITE? "writ": "read"), (long)fd_req->sector);
625 	end_request(fd_req, 0);
626 	fs->state = idle;
627 	start_request(fs);
628 }
629 
630 static irqreturn_t swim3_interrupt(int irq, void *dev_id, struct pt_regs *regs)
631 {
632 	struct floppy_state *fs = (struct floppy_state *) dev_id;
633 	struct swim3 __iomem *sw = fs->swim3;
634 	int intr, err, n;
635 	int stat, resid;
636 	struct dbdma_regs __iomem *dr;
637 	struct dbdma_cmd *cp;
638 
639 	intr = in_8(&sw->intr);
640 	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
641 	if ((intr & ERROR_INTR) && fs->state != do_transfer)
642 		printk(KERN_ERR "swim3_interrupt, state=%d, dir=%lx, intr=%x, err=%x\n",
643 		       fs->state, rq_data_dir(fd_req), intr, err);
644 	switch (fs->state) {
645 	case locating:
646 		if (intr & SEEN_SECTOR) {
647 			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
648 			out_8(&sw->select, RELAX);
649 			out_8(&sw->intr_enable, 0);
650 			del_timer(&fs->timeout);
651 			fs->timeout_pending = 0;
652 			if (sw->ctrack == 0xff) {
653 				printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
654 				fs->cur_cyl = -1;
655 				if (fs->retries > 5) {
656 					end_request(fd_req, 0);
657 					fs->state = idle;
658 					start_request(fs);
659 				} else {
660 					fs->state = jogging;
661 					act(fs);
662 				}
663 				break;
664 			}
665 			fs->cur_cyl = sw->ctrack;
666 			fs->cur_sector = sw->csect;
667 			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
668 				printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
669 				       fs->expect_cyl, fs->cur_cyl);
670 			fs->state = do_transfer;
671 			act(fs);
672 		}
673 		break;
674 	case seeking:
675 	case jogging:
676 		if (sw->nseek == 0) {
677 			out_8(&sw->control_bic, DO_SEEK);
678 			out_8(&sw->select, RELAX);
679 			out_8(&sw->intr_enable, 0);
680 			del_timer(&fs->timeout);
681 			fs->timeout_pending = 0;
682 			if (fs->state == seeking)
683 				++fs->retries;
684 			fs->state = settling;
685 			act(fs);
686 		}
687 		break;
688 	case settling:
689 		out_8(&sw->intr_enable, 0);
690 		del_timer(&fs->timeout);
691 		fs->timeout_pending = 0;
692 		act(fs);
693 		break;
694 	case do_transfer:
695 		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
696 			break;
697 		out_8(&sw->intr_enable, 0);
698 		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
699 		out_8(&sw->select, RELAX);
700 		del_timer(&fs->timeout);
701 		fs->timeout_pending = 0;
702 		dr = fs->dma;
703 		cp = fs->dma_cmd;
704 		if (rq_data_dir(fd_req) == WRITE)
705 			++cp;
706 		/*
707 		 * Check that the main data transfer has finished.
708 		 * On writing, the swim3 sometimes doesn't use
709 		 * up all the bytes of the postamble, so we can still
710 		 * see DMA active here.  That doesn't matter as long
711 		 * as all the sector data has been transferred.
712 		 */
713 		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
714 			/* wait a little while for DMA to complete */
715 			for (n = 0; n < 100; ++n) {
716 				if (cp->xfer_status != 0)
717 					break;
718 				udelay(1);
719 				barrier();
720 			}
721 		}
722 		/* turn off DMA */
723 		out_le32(&dr->control, (RUN | PAUSE) << 16);
724 		stat = ld_le16(&cp->xfer_status);
725 		resid = ld_le16(&cp->res_count);
726 		if (intr & ERROR_INTR) {
727 			n = fs->scount - 1 - resid / 512;
728 			if (n > 0) {
729 				fd_req->sector += n;
730 				fd_req->current_nr_sectors -= n;
731 				fd_req->buffer += n * 512;
732 				fs->req_sector += n;
733 			}
734 			if (fs->retries < 5) {
735 				++fs->retries;
736 				act(fs);
737 			} else {
738 				printk("swim3: error %sing block %ld (err=%x)\n",
739 				       rq_data_dir(fd_req) == WRITE? "writ": "read",
740 				       (long)fd_req->sector, err);
741 				end_request(fd_req, 0);
742 				fs->state = idle;
743 			}
744 		} else {
745 			if ((stat & ACTIVE) == 0 || resid != 0) {
746 				/* musta been an error */
747 				printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
748 				printk(KERN_ERR "  state=%d, dir=%lx, intr=%x, err=%x\n",
749 				       fs->state, rq_data_dir(fd_req), intr, err);
750 				end_request(fd_req, 0);
751 				fs->state = idle;
752 				start_request(fs);
753 				break;
754 			}
755 			fd_req->sector += fs->scount;
756 			fd_req->current_nr_sectors -= fs->scount;
757 			fd_req->buffer += fs->scount * 512;
758 			if (fd_req->current_nr_sectors <= 0) {
759 				end_request(fd_req, 1);
760 				fs->state = idle;
761 			} else {
762 				fs->req_sector += fs->scount;
763 				if (fs->req_sector > fs->secpertrack) {
764 					fs->req_sector -= fs->secpertrack;
765 					if (++fs->head > 1) {
766 						fs->head = 0;
767 						++fs->req_cyl;
768 					}
769 				}
770 				act(fs);
771 			}
772 		}
773 		if (fs->state == idle)
774 			start_request(fs);
775 		break;
776 	default:
777 		printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
778 	}
779 	return IRQ_HANDLED;
780 }
781 
782 /*
783 static void fd_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
784 {
785 }
786 */
787 
788 static int grab_drive(struct floppy_state *fs, enum swim_state state,
789 		      int interruptible)
790 {
791 	unsigned long flags;
792 
793 	save_flags(flags);
794 	cli();
795 	if (fs->state != idle) {
796 		++fs->wanted;
797 		while (fs->state != available) {
798 			if (interruptible && signal_pending(current)) {
799 				--fs->wanted;
800 				restore_flags(flags);
801 				return -EINTR;
802 			}
803 			interruptible_sleep_on(&fs->wait);
804 		}
805 		--fs->wanted;
806 	}
807 	fs->state = state;
808 	restore_flags(flags);
809 	return 0;
810 }
811 
812 static void release_drive(struct floppy_state *fs)
813 {
814 	unsigned long flags;
815 
816 	save_flags(flags);
817 	cli();
818 	fs->state = idle;
819 	start_request(fs);
820 	restore_flags(flags);
821 }
822 
823 static int fd_eject(struct floppy_state *fs)
824 {
825 	int err, n;
826 
827 	err = grab_drive(fs, ejecting, 1);
828 	if (err)
829 		return err;
830 	swim3_action(fs, EJECT);
831 	for (n = 20; n > 0; --n) {
832 		if (signal_pending(current)) {
833 			err = -EINTR;
834 			break;
835 		}
836 		swim3_select(fs, RELAX);
837 		schedule_timeout_interruptible(1);
838 		if (swim3_readbit(fs, DISK_IN) == 0)
839 			break;
840 	}
841 	swim3_select(fs, RELAX);
842 	udelay(150);
843 	fs->ejected = 1;
844 	release_drive(fs);
845 	return err;
846 }
847 
848 static struct floppy_struct floppy_type =
849 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
850 
851 static int floppy_ioctl(struct inode *inode, struct file *filp,
852 			unsigned int cmd, unsigned long param)
853 {
854 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
855 	int err;
856 
857 	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
858 		return -EPERM;
859 
860 #ifdef CONFIG_PMAC_MEDIABAY
861 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
862 		return -ENXIO;
863 #endif
864 
865 	switch (cmd) {
866 	case FDEJECT:
867 		if (fs->ref_count != 1)
868 			return -EBUSY;
869 		err = fd_eject(fs);
870 		return err;
871 	case FDGETPRM:
872 	        if (copy_to_user((void __user *) param, &floppy_type,
873 				 sizeof(struct floppy_struct)))
874 			return -EFAULT;
875 		return 0;
876 	}
877 	return -ENOTTY;
878 }
879 
880 static int floppy_open(struct inode *inode, struct file *filp)
881 {
882 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
883 	struct swim3 __iomem *sw = fs->swim3;
884 	int n, err = 0;
885 
886 	if (fs->ref_count == 0) {
887 #ifdef CONFIG_PMAC_MEDIABAY
888 		if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
889 			return -ENXIO;
890 #endif
891 		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
892 		out_8(&sw->control_bic, 0xff);
893 		out_8(&sw->mode, 0x95);
894 		udelay(10);
895 		out_8(&sw->intr_enable, 0);
896 		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
897 		swim3_action(fs, MOTOR_ON);
898 		fs->write_prot = -1;
899 		fs->cur_cyl = -1;
900 		for (n = 0; n < 2 * HZ; ++n) {
901 			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
902 				break;
903 			if (signal_pending(current)) {
904 				err = -EINTR;
905 				break;
906 			}
907 			swim3_select(fs, RELAX);
908 			schedule_timeout_interruptible(1);
909 		}
910 		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
911 				 || swim3_readbit(fs, DISK_IN) == 0))
912 			err = -ENXIO;
913 		swim3_action(fs, SETMFM);
914 		swim3_select(fs, RELAX);
915 
916 	} else if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
917 		return -EBUSY;
918 
919 	if (err == 0 && (filp->f_flags & O_NDELAY) == 0
920 	    && (filp->f_mode & 3)) {
921 		check_disk_change(inode->i_bdev);
922 		if (fs->ejected)
923 			err = -ENXIO;
924 	}
925 
926 	if (err == 0 && (filp->f_mode & 2)) {
927 		if (fs->write_prot < 0)
928 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
929 		if (fs->write_prot)
930 			err = -EROFS;
931 	}
932 
933 	if (err) {
934 		if (fs->ref_count == 0) {
935 			swim3_action(fs, MOTOR_OFF);
936 			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
937 			swim3_select(fs, RELAX);
938 		}
939 		return err;
940 	}
941 
942 	if (filp->f_flags & O_EXCL)
943 		fs->ref_count = -1;
944 	else
945 		++fs->ref_count;
946 
947 	return 0;
948 }
949 
950 static int floppy_release(struct inode *inode, struct file *filp)
951 {
952 	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
953 	struct swim3 __iomem *sw = fs->swim3;
954 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
955 		swim3_action(fs, MOTOR_OFF);
956 		out_8(&sw->control_bic, 0xff);
957 		swim3_select(fs, RELAX);
958 	}
959 	return 0;
960 }
961 
962 static int floppy_check_change(struct gendisk *disk)
963 {
964 	struct floppy_state *fs = disk->private_data;
965 	return fs->ejected;
966 }
967 
968 static int floppy_revalidate(struct gendisk *disk)
969 {
970 	struct floppy_state *fs = disk->private_data;
971 	struct swim3 __iomem *sw;
972 	int ret, n;
973 
974 #ifdef CONFIG_PMAC_MEDIABAY
975 	if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
976 		return -ENXIO;
977 #endif
978 
979 	sw = fs->swim3;
980 	grab_drive(fs, revalidating, 0);
981 	out_8(&sw->intr_enable, 0);
982 	out_8(&sw->control_bis, DRIVE_ENABLE);
983 	swim3_action(fs, MOTOR_ON);	/* necessary? */
984 	fs->write_prot = -1;
985 	fs->cur_cyl = -1;
986 	mdelay(1);
987 	for (n = HZ; n > 0; --n) {
988 		if (swim3_readbit(fs, SEEK_COMPLETE))
989 			break;
990 		if (signal_pending(current))
991 			break;
992 		swim3_select(fs, RELAX);
993 		schedule_timeout_interruptible(1);
994 	}
995 	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
996 		|| swim3_readbit(fs, DISK_IN) == 0;
997 	if (ret)
998 		swim3_action(fs, MOTOR_OFF);
999 	else {
1000 		fs->ejected = 0;
1001 		swim3_action(fs, SETMFM);
1002 	}
1003 	swim3_select(fs, RELAX);
1004 
1005 	release_drive(fs);
1006 	return ret;
1007 }
1008 
1009 static struct block_device_operations floppy_fops = {
1010 	.open		= floppy_open,
1011 	.release	= floppy_release,
1012 	.ioctl		= floppy_ioctl,
1013 	.media_changed	= floppy_check_change,
1014 	.revalidate_disk= floppy_revalidate,
1015 };
1016 
1017 int swim3_init(void)
1018 {
1019 	struct device_node *swim;
1020 	int err = -ENOMEM;
1021 	int i;
1022 
1023 	devfs_mk_dir("floppy");
1024 
1025 	swim = find_devices("floppy");
1026 	while (swim && (floppy_count < MAX_FLOPPIES))
1027 	{
1028 		swim3_add_device(swim);
1029 		swim = swim->next;
1030 	}
1031 
1032 	swim = find_devices("swim3");
1033 	while (swim && (floppy_count < MAX_FLOPPIES))
1034 	{
1035 		swim3_add_device(swim);
1036 		swim = swim->next;
1037 	}
1038 
1039 	if (!floppy_count)
1040 		return -ENODEV;
1041 
1042 	for (i = 0; i < floppy_count; i++) {
1043 		disks[i] = alloc_disk(1);
1044 		if (!disks[i])
1045 			goto out;
1046 	}
1047 
1048 	if (register_blkdev(FLOPPY_MAJOR, "fd")) {
1049 		err = -EBUSY;
1050 		goto out;
1051 	}
1052 
1053 	swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1054 	if (!swim3_queue) {
1055 		err = -ENOMEM;
1056 		goto out_queue;
1057 	}
1058 
1059 	for (i = 0; i < floppy_count; i++) {
1060 		struct gendisk *disk = disks[i];
1061 		disk->major = FLOPPY_MAJOR;
1062 		disk->first_minor = i;
1063 		disk->fops = &floppy_fops;
1064 		disk->private_data = &floppy_states[i];
1065 		disk->queue = swim3_queue;
1066 		disk->flags |= GENHD_FL_REMOVABLE;
1067 		sprintf(disk->disk_name, "fd%d", i);
1068 		sprintf(disk->devfs_name, "floppy/%d", i);
1069 		set_capacity(disk, 2880);
1070 		add_disk(disk);
1071 	}
1072 	return 0;
1073 
1074 out_queue:
1075 	unregister_blkdev(FLOPPY_MAJOR, "fd");
1076 out:
1077 	while (i--)
1078 		put_disk(disks[i]);
1079 	/* shouldn't we do something with results of swim_add_device()? */
1080 	return err;
1081 }
1082 
1083 static int swim3_add_device(struct device_node *swim)
1084 {
1085 	struct device_node *mediabay;
1086 	struct floppy_state *fs = &floppy_states[floppy_count];
1087 
1088 	if (swim->n_addrs < 2)
1089 	{
1090 		printk(KERN_INFO "swim3: expecting 2 addrs (n_addrs:%d, n_intrs:%d)\n",
1091 		       swim->n_addrs, swim->n_intrs);
1092 		return -EINVAL;
1093 	}
1094 
1095 	if (swim->n_intrs < 2)
1096 	{
1097 		printk(KERN_INFO "swim3: expecting 2 intrs (n_addrs:%d, n_intrs:%d)\n",
1098 		       swim->n_addrs, swim->n_intrs);
1099 		return -EINVAL;
1100 	}
1101 
1102 	if (!request_OF_resource(swim, 0, NULL)) {
1103 		printk(KERN_INFO "swim3: can't request IO resource !\n");
1104 		return -EINVAL;
1105 	}
1106 
1107 	mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ? swim->parent : NULL;
1108 	if (mediabay == NULL)
1109 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1110 
1111 	memset(fs, 0, sizeof(*fs));
1112 	fs->state = idle;
1113 	fs->swim3 = (struct swim3 __iomem *)
1114 		ioremap(swim->addrs[0].address, 0x200);
1115 	fs->dma = (struct dbdma_regs __iomem *)
1116 		ioremap(swim->addrs[1].address, 0x200);
1117 	fs->swim3_intr = swim->intrs[0].line;
1118 	fs->dma_intr = swim->intrs[1].line;
1119 	fs->cur_cyl = -1;
1120 	fs->cur_sector = -1;
1121 	fs->secpercyl = 36;
1122 	fs->secpertrack = 18;
1123 	fs->total_secs = 2880;
1124 	fs->media_bay = mediabay;
1125 	init_waitqueue_head(&fs->wait);
1126 
1127 	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1128 	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1129 	st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1130 
1131 	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1132 		printk(KERN_ERR "Couldn't get irq %d for SWIM3\n", fs->swim3_intr);
1133 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1134 		return -EBUSY;
1135 	}
1136 /*
1137 	if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1138 		printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1139 		       fs->dma_intr);
1140 		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1141 		return -EBUSY;
1142 	}
1143 */
1144 
1145 	init_timer(&fs->timeout);
1146 
1147 	printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1148 		mediabay ? "in media bay" : "");
1149 
1150 	floppy_count++;
1151 
1152 	return 0;
1153 }
1154 
1155 module_init(swim3_init)
1156 
1157 MODULE_LICENSE("GPL");
1158 MODULE_AUTHOR("Paul Mackerras");
1159 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1160