xref: /kernel/linux/linux-5.10/drivers/block/swim3.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Driver for the SWIM3 (Super Woz Integrated Machine 3)
4 * floppy controller found on Power Macintoshes.
5 *
6 * Copyright (C) 1996 Paul Mackerras.
7 */
8
9/*
10 * TODO:
11 * handle 2 drives
12 * handle GCR disks
13 */
14
15#undef DEBUG
16
17#include <linux/stddef.h>
18#include <linux/kernel.h>
19#include <linux/sched/signal.h>
20#include <linux/timer.h>
21#include <linux/delay.h>
22#include <linux/fd.h>
23#include <linux/ioctl.h>
24#include <linux/blk-mq.h>
25#include <linux/interrupt.h>
26#include <linux/mutex.h>
27#include <linux/module.h>
28#include <linux/spinlock.h>
29#include <linux/wait.h>
30#include <asm/io.h>
31#include <asm/dbdma.h>
32#include <asm/prom.h>
33#include <linux/uaccess.h>
34#include <asm/mediabay.h>
35#include <asm/machdep.h>
36#include <asm/pmac_feature.h>
37
38#define MAX_FLOPPIES	2
39
40static DEFINE_MUTEX(swim3_mutex);
41static struct gendisk *disks[MAX_FLOPPIES];
42
43enum swim_state {
44	idle,
45	locating,
46	seeking,
47	settling,
48	do_transfer,
49	jogging,
50	available,
51	revalidating,
52	ejecting
53};
54
55#define REG(x)	unsigned char x; char x ## _pad[15];
56
57/*
58 * The names for these registers mostly represent speculation on my part.
59 * It will be interesting to see how close they are to the names Apple uses.
60 */
61struct swim3 {
62	REG(data);
63	REG(timer);		/* counts down at 1MHz */
64	REG(error);
65	REG(mode);
66	REG(select);		/* controls CA0, CA1, CA2 and LSTRB signals */
67	REG(setup);
68	REG(control);		/* writing bits clears them */
69	REG(status);		/* writing bits sets them in control */
70	REG(intr);
71	REG(nseek);		/* # tracks to seek */
72	REG(ctrack);		/* current track number */
73	REG(csect);		/* current sector number */
74	REG(gap3);		/* size of gap 3 in track format */
75	REG(sector);		/* sector # to read or write */
76	REG(nsect);		/* # sectors to read or write */
77	REG(intr_enable);
78};
79
80#define control_bic	control
81#define control_bis	status
82
83/* Bits in select register */
84#define CA_MASK		7
85#define LSTRB		8
86
87/* Bits in control register */
88#define DO_SEEK		0x80
89#define FORMAT		0x40
90#define SELECT		0x20
91#define WRITE_SECTORS	0x10
92#define DO_ACTION	0x08
93#define DRIVE2_ENABLE	0x04
94#define DRIVE_ENABLE	0x02
95#define INTR_ENABLE	0x01
96
97/* Bits in status register */
98#define FIFO_1BYTE	0x80
99#define FIFO_2BYTE	0x40
100#define ERROR		0x20
101#define DATA		0x08
102#define RDDATA		0x04
103#define INTR_PENDING	0x02
104#define MARK_BYTE	0x01
105
106/* Bits in intr and intr_enable registers */
107#define ERROR_INTR	0x20
108#define DATA_CHANGED	0x10
109#define TRANSFER_DONE	0x08
110#define SEEN_SECTOR	0x04
111#define SEEK_DONE	0x02
112#define TIMER_DONE	0x01
113
114/* Bits in error register */
115#define ERR_DATA_CRC	0x80
116#define ERR_ADDR_CRC	0x40
117#define ERR_OVERRUN	0x04
118#define ERR_UNDERRUN	0x01
119
120/* Bits in setup register */
121#define S_SW_RESET	0x80
122#define S_GCR_WRITE	0x40
123#define S_IBM_DRIVE	0x20
124#define S_TEST_MODE	0x10
125#define S_FCLK_DIV2	0x08
126#define S_GCR		0x04
127#define S_COPY_PROT	0x02
128#define S_INV_WDATA	0x01
129
130/* Select values for swim3_action */
131#define SEEK_POSITIVE	0
132#define SEEK_NEGATIVE	4
133#define STEP		1
134#define MOTOR_ON	2
135#define MOTOR_OFF	6
136#define INDEX		3
137#define EJECT		7
138#define SETMFM		9
139#define SETGCR		13
140
141/* Select values for swim3_select and swim3_readbit */
142#define STEP_DIR	0
143#define STEPPING	1
144#define MOTOR_ON	2
145#define RELAX		3	/* also eject in progress */
146#define READ_DATA_0	4
147#define ONEMEG_DRIVE	5
148#define SINGLE_SIDED	6	/* drive or diskette is 4MB type? */
149#define DRIVE_PRESENT	7
150#define DISK_IN		8
151#define WRITE_PROT	9
152#define TRACK_ZERO	10
153#define TACHO		11
154#define READ_DATA_1	12
155#define GCR_MODE	13
156#define SEEK_COMPLETE	14
157#define TWOMEG_MEDIA	15
158
159/* Definitions of values used in writing and formatting */
160#define DATA_ESCAPE	0x99
161#define GCR_SYNC_EXC	0x3f
162#define GCR_SYNC_CONV	0x80
163#define GCR_FIRST_MARK	0xd5
164#define GCR_SECOND_MARK	0xaa
165#define GCR_ADDR_MARK	"\xd5\xaa\x00"
166#define GCR_DATA_MARK	"\xd5\xaa\x0b"
167#define GCR_SLIP_BYTE	"\x27\xaa"
168#define GCR_SELF_SYNC	"\x3f\xbf\x1e\x34\x3c\x3f"
169
170#define DATA_99		"\x99\x99"
171#define MFM_ADDR_MARK	"\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
172#define MFM_INDEX_MARK	"\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
173#define MFM_GAP_LEN	12
174
175struct floppy_state {
176	enum swim_state	state;
177	struct swim3 __iomem *swim3;	/* hardware registers */
178	struct dbdma_regs __iomem *dma;	/* DMA controller registers */
179	int	swim3_intr;	/* interrupt number for SWIM3 */
180	int	dma_intr;	/* interrupt number for DMA channel */
181	int	cur_cyl;	/* cylinder head is on, or -1 */
182	int	cur_sector;	/* last sector we saw go past */
183	int	req_cyl;	/* the cylinder for the current r/w request */
184	int	head;		/* head number ditto */
185	int	req_sector;	/* sector number ditto */
186	int	scount;		/* # sectors we're transferring at present */
187	int	retries;
188	int	settle_time;
189	int	secpercyl;	/* disk geometry information */
190	int	secpertrack;
191	int	total_secs;
192	int	write_prot;	/* 1 if write-protected, 0 if not, -1 dunno */
193	struct dbdma_cmd *dma_cmd;
194	int	ref_count;
195	int	expect_cyl;
196	struct timer_list timeout;
197	int	timeout_pending;
198	int	ejected;
199	wait_queue_head_t wait;
200	int	wanted;
201	struct macio_dev *mdev;
202	char	dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
203	int	index;
204	struct request *cur_req;
205	struct blk_mq_tag_set tag_set;
206};
207
208#define swim3_err(fmt, arg...)	dev_err(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
209#define swim3_warn(fmt, arg...)	dev_warn(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
210#define swim3_info(fmt, arg...)	dev_info(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
211
212#ifdef DEBUG
213#define swim3_dbg(fmt, arg...)	dev_dbg(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
214#else
215#define swim3_dbg(fmt, arg...)	do { } while(0)
216#endif
217
218static struct floppy_state floppy_states[MAX_FLOPPIES];
219static int floppy_count = 0;
220static DEFINE_SPINLOCK(swim3_lock);
221
222static unsigned short write_preamble[] = {
223	0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e,	/* gap field */
224	0, 0, 0, 0, 0, 0,			/* sync field */
225	0x99a1, 0x99a1, 0x99a1, 0x99fb,		/* data address mark */
226	0x990f					/* no escape for 512 bytes */
227};
228
229static unsigned short write_postamble[] = {
230	0x9904,					/* insert CRC */
231	0x4e4e, 0x4e4e,
232	0x9908,					/* stop writing */
233	0, 0, 0, 0, 0, 0
234};
235
236static void seek_track(struct floppy_state *fs, int n);
237static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
238static void act(struct floppy_state *fs);
239static void scan_timeout(struct timer_list *t);
240static void seek_timeout(struct timer_list *t);
241static void settle_timeout(struct timer_list *t);
242static void xfer_timeout(struct timer_list *t);
243static irqreturn_t swim3_interrupt(int irq, void *dev_id);
244/*static void fd_dma_interrupt(int irq, void *dev_id);*/
245static int grab_drive(struct floppy_state *fs, enum swim_state state,
246		      int interruptible);
247static void release_drive(struct floppy_state *fs);
248static int fd_eject(struct floppy_state *fs);
249static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
250			unsigned int cmd, unsigned long param);
251static int floppy_open(struct block_device *bdev, fmode_t mode);
252static void floppy_release(struct gendisk *disk, fmode_t mode);
253static unsigned int floppy_check_events(struct gendisk *disk,
254					unsigned int clearing);
255static int floppy_revalidate(struct gendisk *disk);
256
257static bool swim3_end_request(struct floppy_state *fs, blk_status_t err, unsigned int nr_bytes)
258{
259	struct request *req = fs->cur_req;
260
261	swim3_dbg("  end request, err=%d nr_bytes=%d, cur_req=%p\n",
262		  err, nr_bytes, req);
263
264	if (err)
265		nr_bytes = blk_rq_cur_bytes(req);
266	if (blk_update_request(req, err, nr_bytes))
267		return true;
268	__blk_mq_end_request(req, err);
269	fs->cur_req = NULL;
270	return false;
271}
272
273static void swim3_select(struct floppy_state *fs, int sel)
274{
275	struct swim3 __iomem *sw = fs->swim3;
276
277	out_8(&sw->select, RELAX);
278	if (sel & 8)
279		out_8(&sw->control_bis, SELECT);
280	else
281		out_8(&sw->control_bic, SELECT);
282	out_8(&sw->select, sel & CA_MASK);
283}
284
285static void swim3_action(struct floppy_state *fs, int action)
286{
287	struct swim3 __iomem *sw = fs->swim3;
288
289	swim3_select(fs, action);
290	udelay(1);
291	out_8(&sw->select, sw->select | LSTRB);
292	udelay(2);
293	out_8(&sw->select, sw->select & ~LSTRB);
294	udelay(1);
295}
296
297static int swim3_readbit(struct floppy_state *fs, int bit)
298{
299	struct swim3 __iomem *sw = fs->swim3;
300	int stat;
301
302	swim3_select(fs, bit);
303	udelay(1);
304	stat = in_8(&sw->status);
305	return (stat & DATA) == 0;
306}
307
308static blk_status_t swim3_queue_rq(struct blk_mq_hw_ctx *hctx,
309				   const struct blk_mq_queue_data *bd)
310{
311	struct floppy_state *fs = hctx->queue->queuedata;
312	struct request *req = bd->rq;
313	unsigned long x;
314
315	spin_lock_irq(&swim3_lock);
316	if (fs->cur_req || fs->state != idle) {
317		spin_unlock_irq(&swim3_lock);
318		return BLK_STS_DEV_RESOURCE;
319	}
320	blk_mq_start_request(req);
321	fs->cur_req = req;
322	if (fs->mdev->media_bay &&
323	    check_media_bay(fs->mdev->media_bay) != MB_FD) {
324		swim3_dbg("%s", "  media bay absent, dropping req\n");
325		swim3_end_request(fs, BLK_STS_IOERR, 0);
326		goto out;
327	}
328	if (fs->ejected) {
329		swim3_dbg("%s", "  disk ejected\n");
330		swim3_end_request(fs, BLK_STS_IOERR, 0);
331		goto out;
332	}
333	if (rq_data_dir(req) == WRITE) {
334		if (fs->write_prot < 0)
335			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
336		if (fs->write_prot) {
337			swim3_dbg("%s", "  try to write, disk write protected\n");
338			swim3_end_request(fs, BLK_STS_IOERR, 0);
339			goto out;
340		}
341	}
342
343	/*
344	 * Do not remove the cast. blk_rq_pos(req) is now a sector_t and can be
345	 * 64 bits, but it will never go past 32 bits for this driver anyway, so
346	 * we can safely cast it down and not have to do a 64/32 division
347	 */
348	fs->req_cyl = ((long)blk_rq_pos(req)) / fs->secpercyl;
349	x = ((long)blk_rq_pos(req)) % fs->secpercyl;
350	fs->head = x / fs->secpertrack;
351	fs->req_sector = x % fs->secpertrack + 1;
352	fs->state = do_transfer;
353	fs->retries = 0;
354
355	act(fs);
356
357out:
358	spin_unlock_irq(&swim3_lock);
359	return BLK_STS_OK;
360}
361
362static void set_timeout(struct floppy_state *fs, int nticks,
363			void (*proc)(struct timer_list *t))
364{
365	if (fs->timeout_pending)
366		del_timer(&fs->timeout);
367	fs->timeout.expires = jiffies + nticks;
368	fs->timeout.function = proc;
369	add_timer(&fs->timeout);
370	fs->timeout_pending = 1;
371}
372
373static inline void scan_track(struct floppy_state *fs)
374{
375	struct swim3 __iomem *sw = fs->swim3;
376
377	swim3_select(fs, READ_DATA_0);
378	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
379	in_8(&sw->error);
380	out_8(&sw->intr_enable, SEEN_SECTOR);
381	out_8(&sw->control_bis, DO_ACTION);
382	/* enable intr when track found */
383	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
384}
385
386static inline void seek_track(struct floppy_state *fs, int n)
387{
388	struct swim3 __iomem *sw = fs->swim3;
389
390	if (n >= 0) {
391		swim3_action(fs, SEEK_POSITIVE);
392		sw->nseek = n;
393	} else {
394		swim3_action(fs, SEEK_NEGATIVE);
395		sw->nseek = -n;
396	}
397	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
398	swim3_select(fs, STEP);
399	in_8(&sw->error);
400	/* enable intr when seek finished */
401	out_8(&sw->intr_enable, SEEK_DONE);
402	out_8(&sw->control_bis, DO_SEEK);
403	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
404	fs->settle_time = 0;
405}
406
407static inline void init_dma(struct dbdma_cmd *cp, int cmd,
408			    void *buf, int count)
409{
410	cp->req_count = cpu_to_le16(count);
411	cp->command = cpu_to_le16(cmd);
412	cp->phy_addr = cpu_to_le32(virt_to_bus(buf));
413	cp->xfer_status = 0;
414}
415
416static inline void setup_transfer(struct floppy_state *fs)
417{
418	int n;
419	struct swim3 __iomem *sw = fs->swim3;
420	struct dbdma_cmd *cp = fs->dma_cmd;
421	struct dbdma_regs __iomem *dr = fs->dma;
422	struct request *req = fs->cur_req;
423
424	if (blk_rq_cur_sectors(req) <= 0) {
425		swim3_warn("%s", "Transfer 0 sectors ?\n");
426		return;
427	}
428	if (rq_data_dir(req) == WRITE)
429		n = 1;
430	else {
431		n = fs->secpertrack - fs->req_sector + 1;
432		if (n > blk_rq_cur_sectors(req))
433			n = blk_rq_cur_sectors(req);
434	}
435
436	swim3_dbg("  setup xfer at sect %d (of %d) head %d for %d\n",
437		  fs->req_sector, fs->secpertrack, fs->head, n);
438
439	fs->scount = n;
440	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
441	out_8(&sw->sector, fs->req_sector);
442	out_8(&sw->nsect, n);
443	out_8(&sw->gap3, 0);
444	out_le32(&dr->cmdptr, virt_to_bus(cp));
445	if (rq_data_dir(req) == WRITE) {
446		/* Set up 3 dma commands: write preamble, data, postamble */
447		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
448		++cp;
449		init_dma(cp, OUTPUT_MORE, bio_data(req->bio), 512);
450		++cp;
451		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
452	} else {
453		init_dma(cp, INPUT_LAST, bio_data(req->bio), n * 512);
454	}
455	++cp;
456	out_le16(&cp->command, DBDMA_STOP);
457	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
458	in_8(&sw->error);
459	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
460	if (rq_data_dir(req) == WRITE)
461		out_8(&sw->control_bis, WRITE_SECTORS);
462	in_8(&sw->intr);
463	out_le32(&dr->control, (RUN << 16) | RUN);
464	/* enable intr when transfer complete */
465	out_8(&sw->intr_enable, TRANSFER_DONE);
466	out_8(&sw->control_bis, DO_ACTION);
467	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
468}
469
470static void act(struct floppy_state *fs)
471{
472	for (;;) {
473		swim3_dbg("  act loop, state=%d, req_cyl=%d, cur_cyl=%d\n",
474			  fs->state, fs->req_cyl, fs->cur_cyl);
475
476		switch (fs->state) {
477		case idle:
478			return;		/* XXX shouldn't get here */
479
480		case locating:
481			if (swim3_readbit(fs, TRACK_ZERO)) {
482				swim3_dbg("%s", "    locate track 0\n");
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				swim3_warn("%s", "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					swim3_err("Wrong cylinder in transfer, want: %d got %d\n",
517						  fs->req_cyl, fs->cur_cyl);
518					swim3_end_request(fs, BLK_STS_IOERR, 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			swim3_err("Unknown state %d\n", fs->state);
534			return;
535		}
536	}
537}
538
539static void scan_timeout(struct timer_list *t)
540{
541	struct floppy_state *fs = from_timer(fs, t, timeout);
542	struct swim3 __iomem *sw = fs->swim3;
543	unsigned long flags;
544
545	swim3_dbg("* scan timeout, state=%d\n", fs->state);
546
547	spin_lock_irqsave(&swim3_lock, flags);
548	fs->timeout_pending = 0;
549	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
550	out_8(&sw->select, RELAX);
551	out_8(&sw->intr_enable, 0);
552	fs->cur_cyl = -1;
553	if (fs->retries > 5) {
554		swim3_end_request(fs, BLK_STS_IOERR, 0);
555		fs->state = idle;
556	} else {
557		fs->state = jogging;
558		act(fs);
559	}
560	spin_unlock_irqrestore(&swim3_lock, flags);
561}
562
563static void seek_timeout(struct timer_list *t)
564{
565	struct floppy_state *fs = from_timer(fs, t, timeout);
566	struct swim3 __iomem *sw = fs->swim3;
567	unsigned long flags;
568
569	swim3_dbg("* seek timeout, state=%d\n", fs->state);
570
571	spin_lock_irqsave(&swim3_lock, flags);
572	fs->timeout_pending = 0;
573	out_8(&sw->control_bic, DO_SEEK);
574	out_8(&sw->select, RELAX);
575	out_8(&sw->intr_enable, 0);
576	swim3_err("%s", "Seek timeout\n");
577	swim3_end_request(fs, BLK_STS_IOERR, 0);
578	fs->state = idle;
579	spin_unlock_irqrestore(&swim3_lock, flags);
580}
581
582static void settle_timeout(struct timer_list *t)
583{
584	struct floppy_state *fs = from_timer(fs, t, timeout);
585	struct swim3 __iomem *sw = fs->swim3;
586	unsigned long flags;
587
588	swim3_dbg("* settle timeout, state=%d\n", fs->state);
589
590	spin_lock_irqsave(&swim3_lock, flags);
591	fs->timeout_pending = 0;
592	if (swim3_readbit(fs, SEEK_COMPLETE)) {
593		out_8(&sw->select, RELAX);
594		fs->state = locating;
595		act(fs);
596		goto unlock;
597	}
598	out_8(&sw->select, RELAX);
599	if (fs->settle_time < 2*HZ) {
600		++fs->settle_time;
601		set_timeout(fs, 1, settle_timeout);
602		goto unlock;
603	}
604	swim3_err("%s", "Seek settle timeout\n");
605	swim3_end_request(fs, BLK_STS_IOERR, 0);
606	fs->state = idle;
607 unlock:
608	spin_unlock_irqrestore(&swim3_lock, flags);
609}
610
611static void xfer_timeout(struct timer_list *t)
612{
613	struct floppy_state *fs = from_timer(fs, t, timeout);
614	struct swim3 __iomem *sw = fs->swim3;
615	struct dbdma_regs __iomem *dr = fs->dma;
616	unsigned long flags;
617	int n;
618
619	swim3_dbg("* xfer timeout, state=%d\n", fs->state);
620
621	spin_lock_irqsave(&swim3_lock, flags);
622	fs->timeout_pending = 0;
623	out_le32(&dr->control, RUN << 16);
624	/* We must wait a bit for dbdma to stop */
625	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
626		udelay(1);
627	out_8(&sw->intr_enable, 0);
628	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
629	out_8(&sw->select, RELAX);
630	swim3_err("Timeout %sing sector %ld\n",
631	       (rq_data_dir(fs->cur_req)==WRITE? "writ": "read"),
632	       (long)blk_rq_pos(fs->cur_req));
633	swim3_end_request(fs, BLK_STS_IOERR, 0);
634	fs->state = idle;
635	spin_unlock_irqrestore(&swim3_lock, flags);
636}
637
638static irqreturn_t swim3_interrupt(int irq, void *dev_id)
639{
640	struct floppy_state *fs = (struct floppy_state *) dev_id;
641	struct swim3 __iomem *sw = fs->swim3;
642	int intr, err, n;
643	int stat, resid;
644	struct dbdma_regs __iomem *dr;
645	struct dbdma_cmd *cp;
646	unsigned long flags;
647	struct request *req = fs->cur_req;
648
649	swim3_dbg("* interrupt, state=%d\n", fs->state);
650
651	spin_lock_irqsave(&swim3_lock, flags);
652	intr = in_8(&sw->intr);
653	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
654	if ((intr & ERROR_INTR) && fs->state != do_transfer)
655		swim3_err("Non-transfer error interrupt: state=%d, dir=%x, intr=%x, err=%x\n",
656			  fs->state, rq_data_dir(req), intr, err);
657	switch (fs->state) {
658	case locating:
659		if (intr & SEEN_SECTOR) {
660			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
661			out_8(&sw->select, RELAX);
662			out_8(&sw->intr_enable, 0);
663			del_timer(&fs->timeout);
664			fs->timeout_pending = 0;
665			if (sw->ctrack == 0xff) {
666				swim3_err("%s", "Seen sector but cyl=ff?\n");
667				fs->cur_cyl = -1;
668				if (fs->retries > 5) {
669					swim3_end_request(fs, BLK_STS_IOERR, 0);
670					fs->state = idle;
671				} else {
672					fs->state = jogging;
673					act(fs);
674				}
675				break;
676			}
677			fs->cur_cyl = sw->ctrack;
678			fs->cur_sector = sw->csect;
679			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
680				swim3_err("Expected cyl %d, got %d\n",
681					  fs->expect_cyl, fs->cur_cyl);
682			fs->state = do_transfer;
683			act(fs);
684		}
685		break;
686	case seeking:
687	case jogging:
688		if (sw->nseek == 0) {
689			out_8(&sw->control_bic, DO_SEEK);
690			out_8(&sw->select, RELAX);
691			out_8(&sw->intr_enable, 0);
692			del_timer(&fs->timeout);
693			fs->timeout_pending = 0;
694			if (fs->state == seeking)
695				++fs->retries;
696			fs->state = settling;
697			act(fs);
698		}
699		break;
700	case settling:
701		out_8(&sw->intr_enable, 0);
702		del_timer(&fs->timeout);
703		fs->timeout_pending = 0;
704		act(fs);
705		break;
706	case do_transfer:
707		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
708			break;
709		out_8(&sw->intr_enable, 0);
710		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
711		out_8(&sw->select, RELAX);
712		del_timer(&fs->timeout);
713		fs->timeout_pending = 0;
714		dr = fs->dma;
715		cp = fs->dma_cmd;
716		if (rq_data_dir(req) == WRITE)
717			++cp;
718		/*
719		 * Check that the main data transfer has finished.
720		 * On writing, the swim3 sometimes doesn't use
721		 * up all the bytes of the postamble, so we can still
722		 * see DMA active here.  That doesn't matter as long
723		 * as all the sector data has been transferred.
724		 */
725		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
726			/* wait a little while for DMA to complete */
727			for (n = 0; n < 100; ++n) {
728				if (cp->xfer_status != 0)
729					break;
730				udelay(1);
731				barrier();
732			}
733		}
734		/* turn off DMA */
735		out_le32(&dr->control, (RUN | PAUSE) << 16);
736		stat = le16_to_cpu(cp->xfer_status);
737		resid = le16_to_cpu(cp->res_count);
738		if (intr & ERROR_INTR) {
739			n = fs->scount - 1 - resid / 512;
740			if (n > 0) {
741				blk_update_request(req, 0, n << 9);
742				fs->req_sector += n;
743			}
744			if (fs->retries < 5) {
745				++fs->retries;
746				act(fs);
747			} else {
748				swim3_err("Error %sing block %ld (err=%x)\n",
749				       rq_data_dir(req) == WRITE? "writ": "read",
750				       (long)blk_rq_pos(req), err);
751				swim3_end_request(fs, BLK_STS_IOERR, 0);
752				fs->state = idle;
753			}
754		} else {
755			if ((stat & ACTIVE) == 0 || resid != 0) {
756				/* musta been an error */
757				swim3_err("fd dma error: stat=%x resid=%d\n", stat, resid);
758				swim3_err("  state=%d, dir=%x, intr=%x, err=%x\n",
759					  fs->state, rq_data_dir(req), intr, err);
760				swim3_end_request(fs, BLK_STS_IOERR, 0);
761				fs->state = idle;
762				break;
763			}
764			fs->retries = 0;
765			if (swim3_end_request(fs, 0, fs->scount << 9)) {
766				fs->req_sector += fs->scount;
767				if (fs->req_sector > fs->secpertrack) {
768					fs->req_sector -= fs->secpertrack;
769					if (++fs->head > 1) {
770						fs->head = 0;
771						++fs->req_cyl;
772					}
773				}
774				act(fs);
775			} else
776				fs->state = idle;
777		}
778		break;
779	default:
780		swim3_err("Don't know what to do in state %d\n", fs->state);
781	}
782	spin_unlock_irqrestore(&swim3_lock, flags);
783	return IRQ_HANDLED;
784}
785
786/*
787static void fd_dma_interrupt(int irq, void *dev_id)
788{
789}
790*/
791
792/* Called under the mutex to grab exclusive access to a drive */
793static int grab_drive(struct floppy_state *fs, enum swim_state state,
794		      int interruptible)
795{
796	unsigned long flags;
797
798	swim3_dbg("%s", "-> grab drive\n");
799
800	spin_lock_irqsave(&swim3_lock, flags);
801	if (fs->state != idle && fs->state != available) {
802		++fs->wanted;
803		/* this will enable irqs in order to sleep */
804		if (!interruptible)
805			wait_event_lock_irq(fs->wait,
806                                        fs->state == available,
807                                        swim3_lock);
808		else if (wait_event_interruptible_lock_irq(fs->wait,
809					fs->state == available,
810					swim3_lock)) {
811			--fs->wanted;
812			spin_unlock_irqrestore(&swim3_lock, flags);
813			return -EINTR;
814		}
815		--fs->wanted;
816	}
817	fs->state = state;
818	spin_unlock_irqrestore(&swim3_lock, flags);
819
820	return 0;
821}
822
823static void release_drive(struct floppy_state *fs)
824{
825	struct request_queue *q = disks[fs->index]->queue;
826	unsigned long flags;
827
828	swim3_dbg("%s", "-> release drive\n");
829
830	spin_lock_irqsave(&swim3_lock, flags);
831	fs->state = idle;
832	spin_unlock_irqrestore(&swim3_lock, flags);
833
834	blk_mq_freeze_queue(q);
835	blk_mq_quiesce_queue(q);
836	blk_mq_unquiesce_queue(q);
837	blk_mq_unfreeze_queue(q);
838}
839
840static int fd_eject(struct floppy_state *fs)
841{
842	int err, n;
843
844	err = grab_drive(fs, ejecting, 1);
845	if (err)
846		return err;
847	swim3_action(fs, EJECT);
848	for (n = 20; n > 0; --n) {
849		if (signal_pending(current)) {
850			err = -EINTR;
851			break;
852		}
853		swim3_select(fs, RELAX);
854		schedule_timeout_interruptible(1);
855		if (swim3_readbit(fs, DISK_IN) == 0)
856			break;
857	}
858	swim3_select(fs, RELAX);
859	udelay(150);
860	fs->ejected = 1;
861	release_drive(fs);
862	return err;
863}
864
865static struct floppy_struct floppy_type =
866	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
867
868static int floppy_locked_ioctl(struct block_device *bdev, fmode_t mode,
869			unsigned int cmd, unsigned long param)
870{
871	struct floppy_state *fs = bdev->bd_disk->private_data;
872	int err;
873
874	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
875		return -EPERM;
876
877	if (fs->mdev->media_bay &&
878	    check_media_bay(fs->mdev->media_bay) != MB_FD)
879		return -ENXIO;
880
881	switch (cmd) {
882	case FDEJECT:
883		if (fs->ref_count != 1)
884			return -EBUSY;
885		err = fd_eject(fs);
886		return err;
887	case FDGETPRM:
888	        if (copy_to_user((void __user *) param, &floppy_type,
889				 sizeof(struct floppy_struct)))
890			return -EFAULT;
891		return 0;
892	}
893	return -ENOTTY;
894}
895
896static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
897				 unsigned int cmd, unsigned long param)
898{
899	int ret;
900
901	mutex_lock(&swim3_mutex);
902	ret = floppy_locked_ioctl(bdev, mode, cmd, param);
903	mutex_unlock(&swim3_mutex);
904
905	return ret;
906}
907
908static int floppy_open(struct block_device *bdev, fmode_t mode)
909{
910	struct floppy_state *fs = bdev->bd_disk->private_data;
911	struct swim3 __iomem *sw = fs->swim3;
912	int n, err = 0;
913
914	if (fs->ref_count == 0) {
915		if (fs->mdev->media_bay &&
916		    check_media_bay(fs->mdev->media_bay) != MB_FD)
917			return -ENXIO;
918		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
919		out_8(&sw->control_bic, 0xff);
920		out_8(&sw->mode, 0x95);
921		udelay(10);
922		out_8(&sw->intr_enable, 0);
923		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
924		swim3_action(fs, MOTOR_ON);
925		fs->write_prot = -1;
926		fs->cur_cyl = -1;
927		for (n = 0; n < 2 * HZ; ++n) {
928			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
929				break;
930			if (signal_pending(current)) {
931				err = -EINTR;
932				break;
933			}
934			swim3_select(fs, RELAX);
935			schedule_timeout_interruptible(1);
936		}
937		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
938				 || swim3_readbit(fs, DISK_IN) == 0))
939			err = -ENXIO;
940		swim3_action(fs, SETMFM);
941		swim3_select(fs, RELAX);
942
943	} else if (fs->ref_count == -1 || mode & FMODE_EXCL)
944		return -EBUSY;
945
946	if (err == 0 && (mode & FMODE_NDELAY) == 0
947	    && (mode & (FMODE_READ|FMODE_WRITE))) {
948		if (bdev_check_media_change(bdev))
949			floppy_revalidate(bdev->bd_disk);
950		if (fs->ejected)
951			err = -ENXIO;
952	}
953
954	if (err == 0 && (mode & FMODE_WRITE)) {
955		if (fs->write_prot < 0)
956			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
957		if (fs->write_prot)
958			err = -EROFS;
959	}
960
961	if (err) {
962		if (fs->ref_count == 0) {
963			swim3_action(fs, MOTOR_OFF);
964			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
965			swim3_select(fs, RELAX);
966		}
967		return err;
968	}
969
970	if (mode & FMODE_EXCL)
971		fs->ref_count = -1;
972	else
973		++fs->ref_count;
974
975	return 0;
976}
977
978static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
979{
980	int ret;
981
982	mutex_lock(&swim3_mutex);
983	ret = floppy_open(bdev, mode);
984	mutex_unlock(&swim3_mutex);
985
986	return ret;
987}
988
989static void floppy_release(struct gendisk *disk, fmode_t mode)
990{
991	struct floppy_state *fs = disk->private_data;
992	struct swim3 __iomem *sw = fs->swim3;
993
994	mutex_lock(&swim3_mutex);
995	if (fs->ref_count > 0)
996		--fs->ref_count;
997	else if (fs->ref_count == -1)
998		fs->ref_count = 0;
999	if (fs->ref_count == 0) {
1000		swim3_action(fs, MOTOR_OFF);
1001		out_8(&sw->control_bic, 0xff);
1002		swim3_select(fs, RELAX);
1003	}
1004	mutex_unlock(&swim3_mutex);
1005}
1006
1007static unsigned int floppy_check_events(struct gendisk *disk,
1008					unsigned int clearing)
1009{
1010	struct floppy_state *fs = disk->private_data;
1011	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
1012}
1013
1014static int floppy_revalidate(struct gendisk *disk)
1015{
1016	struct floppy_state *fs = disk->private_data;
1017	struct swim3 __iomem *sw;
1018	int ret, n;
1019
1020	if (fs->mdev->media_bay &&
1021	    check_media_bay(fs->mdev->media_bay) != MB_FD)
1022		return -ENXIO;
1023
1024	sw = fs->swim3;
1025	grab_drive(fs, revalidating, 0);
1026	out_8(&sw->intr_enable, 0);
1027	out_8(&sw->control_bis, DRIVE_ENABLE);
1028	swim3_action(fs, MOTOR_ON);	/* necessary? */
1029	fs->write_prot = -1;
1030	fs->cur_cyl = -1;
1031	mdelay(1);
1032	for (n = HZ; n > 0; --n) {
1033		if (swim3_readbit(fs, SEEK_COMPLETE))
1034			break;
1035		if (signal_pending(current))
1036			break;
1037		swim3_select(fs, RELAX);
1038		schedule_timeout_interruptible(1);
1039	}
1040	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
1041		|| swim3_readbit(fs, DISK_IN) == 0;
1042	if (ret)
1043		swim3_action(fs, MOTOR_OFF);
1044	else {
1045		fs->ejected = 0;
1046		swim3_action(fs, SETMFM);
1047	}
1048	swim3_select(fs, RELAX);
1049
1050	release_drive(fs);
1051	return ret;
1052}
1053
1054static const struct block_device_operations floppy_fops = {
1055	.open		= floppy_unlocked_open,
1056	.release	= floppy_release,
1057	.ioctl		= floppy_ioctl,
1058	.check_events	= floppy_check_events,
1059};
1060
1061static const struct blk_mq_ops swim3_mq_ops = {
1062	.queue_rq = swim3_queue_rq,
1063};
1064
1065static void swim3_mb_event(struct macio_dev* mdev, int mb_state)
1066{
1067	struct floppy_state *fs = macio_get_drvdata(mdev);
1068	struct swim3 __iomem *sw;
1069
1070	if (!fs)
1071		return;
1072
1073	sw = fs->swim3;
1074
1075	if (mb_state != MB_FD)
1076		return;
1077
1078	/* Clear state */
1079	out_8(&sw->intr_enable, 0);
1080	in_8(&sw->intr);
1081	in_8(&sw->error);
1082}
1083
1084static int swim3_add_device(struct macio_dev *mdev, int index)
1085{
1086	struct device_node *swim = mdev->ofdev.dev.of_node;
1087	struct floppy_state *fs = &floppy_states[index];
1088	int rc = -EBUSY;
1089
1090	fs->mdev = mdev;
1091	fs->index = index;
1092
1093	/* Check & Request resources */
1094	if (macio_resource_count(mdev) < 2) {
1095		swim3_err("%s", "No address in device-tree\n");
1096		return -ENXIO;
1097	}
1098	if (macio_irq_count(mdev) < 1) {
1099		swim3_err("%s", "No interrupt in device-tree\n");
1100		return -ENXIO;
1101	}
1102	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1103		swim3_err("%s", "Can't request mmio resource\n");
1104		return -EBUSY;
1105	}
1106	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1107		swim3_err("%s", "Can't request dma resource\n");
1108		macio_release_resource(mdev, 0);
1109		return -EBUSY;
1110	}
1111	dev_set_drvdata(&mdev->ofdev.dev, fs);
1112
1113	if (mdev->media_bay == NULL)
1114		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1115
1116	fs->state = idle;
1117	fs->swim3 = (struct swim3 __iomem *)
1118		ioremap(macio_resource_start(mdev, 0), 0x200);
1119	if (fs->swim3 == NULL) {
1120		swim3_err("%s", "Couldn't map mmio registers\n");
1121		rc = -ENOMEM;
1122		goto out_release;
1123	}
1124	fs->dma = (struct dbdma_regs __iomem *)
1125		ioremap(macio_resource_start(mdev, 1), 0x200);
1126	if (fs->dma == NULL) {
1127		swim3_err("%s", "Couldn't map dma registers\n");
1128		iounmap(fs->swim3);
1129		rc = -ENOMEM;
1130		goto out_release;
1131	}
1132	fs->swim3_intr = macio_irq(mdev, 0);
1133	fs->dma_intr = macio_irq(mdev, 1);
1134	fs->cur_cyl = -1;
1135	fs->cur_sector = -1;
1136	fs->secpercyl = 36;
1137	fs->secpertrack = 18;
1138	fs->total_secs = 2880;
1139	init_waitqueue_head(&fs->wait);
1140
1141	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1142	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1143	fs->dma_cmd[1].command = cpu_to_le16(DBDMA_STOP);
1144
1145	if (mdev->media_bay == NULL || check_media_bay(mdev->media_bay) == MB_FD)
1146		swim3_mb_event(mdev, MB_FD);
1147
1148	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1149		swim3_err("%s", "Couldn't request interrupt\n");
1150		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1151		goto out_unmap;
1152	}
1153
1154	timer_setup(&fs->timeout, NULL, 0);
1155
1156	swim3_info("SWIM3 floppy controller %s\n",
1157		mdev->media_bay ? "in media bay" : "");
1158
1159	return 0;
1160
1161 out_unmap:
1162	iounmap(fs->dma);
1163	iounmap(fs->swim3);
1164
1165 out_release:
1166	macio_release_resource(mdev, 0);
1167	macio_release_resource(mdev, 1);
1168
1169	return rc;
1170}
1171
1172static int swim3_attach(struct macio_dev *mdev,
1173			const struct of_device_id *match)
1174{
1175	struct floppy_state *fs;
1176	struct gendisk *disk;
1177	int rc;
1178
1179	if (floppy_count >= MAX_FLOPPIES)
1180		return -ENXIO;
1181
1182	if (floppy_count == 0) {
1183		rc = register_blkdev(FLOPPY_MAJOR, "fd");
1184		if (rc)
1185			return rc;
1186	}
1187
1188	disk = alloc_disk(1);
1189	if (disk == NULL) {
1190		rc = -ENOMEM;
1191		goto out_unregister;
1192	}
1193
1194	fs = &floppy_states[floppy_count];
1195	memset(fs, 0, sizeof(*fs));
1196
1197	disk->queue = blk_mq_init_sq_queue(&fs->tag_set, &swim3_mq_ops, 2,
1198						BLK_MQ_F_SHOULD_MERGE);
1199	if (IS_ERR(disk->queue)) {
1200		rc = PTR_ERR(disk->queue);
1201		disk->queue = NULL;
1202		goto out_put_disk;
1203	}
1204	blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
1205	disk->queue->queuedata = fs;
1206
1207	rc = swim3_add_device(mdev, floppy_count);
1208	if (rc)
1209		goto out_cleanup_queue;
1210
1211	disk->major = FLOPPY_MAJOR;
1212	disk->first_minor = floppy_count;
1213	disk->fops = &floppy_fops;
1214	disk->private_data = fs;
1215	disk->events = DISK_EVENT_MEDIA_CHANGE;
1216	disk->flags |= GENHD_FL_REMOVABLE;
1217	sprintf(disk->disk_name, "fd%d", floppy_count);
1218	set_capacity(disk, 2880);
1219	add_disk(disk);
1220
1221	disks[floppy_count++] = disk;
1222	return 0;
1223
1224out_cleanup_queue:
1225	blk_cleanup_queue(disk->queue);
1226	disk->queue = NULL;
1227	blk_mq_free_tag_set(&fs->tag_set);
1228out_put_disk:
1229	put_disk(disk);
1230out_unregister:
1231	if (floppy_count == 0)
1232		unregister_blkdev(FLOPPY_MAJOR, "fd");
1233	return rc;
1234}
1235
1236static const struct of_device_id swim3_match[] =
1237{
1238	{
1239	.name		= "swim3",
1240	},
1241	{
1242	.compatible	= "ohare-swim3"
1243	},
1244	{
1245	.compatible	= "swim3"
1246	},
1247	{ /* end of list */ }
1248};
1249
1250static struct macio_driver swim3_driver =
1251{
1252	.driver = {
1253		.name 		= "swim3",
1254		.of_match_table	= swim3_match,
1255	},
1256	.probe		= swim3_attach,
1257#ifdef CONFIG_PMAC_MEDIABAY
1258	.mediabay_event	= swim3_mb_event,
1259#endif
1260#if 0
1261	.suspend	= swim3_suspend,
1262	.resume		= swim3_resume,
1263#endif
1264};
1265
1266
1267int swim3_init(void)
1268{
1269	macio_register_driver(&swim3_driver);
1270	return 0;
1271}
1272
1273module_init(swim3_init)
1274
1275MODULE_LICENSE("GPL");
1276MODULE_AUTHOR("Paul Mackerras");
1277MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1278