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 <linux/major.h>
31#include <asm/io.h>
32#include <asm/dbdma.h>
33#include <asm/prom.h>
34#include <linux/uaccess.h>
35#include <asm/mediabay.h>
36#include <asm/machdep.h>
37#include <asm/pmac_feature.h>
38
39#define MAX_FLOPPIES	2
40
41static DEFINE_MUTEX(swim3_mutex);
42static struct gendisk *disks[MAX_FLOPPIES];
43
44enum swim_state {
45	idle,
46	locating,
47	seeking,
48	settling,
49	do_transfer,
50	jogging,
51	available,
52	revalidating,
53	ejecting
54};
55
56#define REG(x)	unsigned char x; char x ## _pad[15];
57
58/*
59 * The names for these registers mostly represent speculation on my part.
60 * It will be interesting to see how close they are to the names Apple uses.
61 */
62struct swim3 {
63	REG(data);
64	REG(timer);		/* counts down at 1MHz */
65	REG(error);
66	REG(mode);
67	REG(select);		/* controls CA0, CA1, CA2 and LSTRB signals */
68	REG(setup);
69	REG(control);		/* writing bits clears them */
70	REG(status);		/* writing bits sets them in control */
71	REG(intr);
72	REG(nseek);		/* # tracks to seek */
73	REG(ctrack);		/* current track number */
74	REG(csect);		/* current sector number */
75	REG(gap3);		/* size of gap 3 in track format */
76	REG(sector);		/* sector # to read or write */
77	REG(nsect);		/* # sectors to read or write */
78	REG(intr_enable);
79};
80
81#define control_bic	control
82#define control_bis	status
83
84/* Bits in select register */
85#define CA_MASK		7
86#define LSTRB		8
87
88/* Bits in control register */
89#define DO_SEEK		0x80
90#define FORMAT		0x40
91#define SELECT		0x20
92#define WRITE_SECTORS	0x10
93#define DO_ACTION	0x08
94#define DRIVE2_ENABLE	0x04
95#define DRIVE_ENABLE	0x02
96#define INTR_ENABLE	0x01
97
98/* Bits in status register */
99#define FIFO_1BYTE	0x80
100#define FIFO_2BYTE	0x40
101#define ERROR		0x20
102#define DATA		0x08
103#define RDDATA		0x04
104#define INTR_PENDING	0x02
105#define MARK_BYTE	0x01
106
107/* Bits in intr and intr_enable registers */
108#define ERROR_INTR	0x20
109#define DATA_CHANGED	0x10
110#define TRANSFER_DONE	0x08
111#define SEEN_SECTOR	0x04
112#define SEEK_DONE	0x02
113#define TIMER_DONE	0x01
114
115/* Bits in error register */
116#define ERR_DATA_CRC	0x80
117#define ERR_ADDR_CRC	0x40
118#define ERR_OVERRUN	0x04
119#define ERR_UNDERRUN	0x01
120
121/* Bits in setup register */
122#define S_SW_RESET	0x80
123#define S_GCR_WRITE	0x40
124#define S_IBM_DRIVE	0x20
125#define S_TEST_MODE	0x10
126#define S_FCLK_DIV2	0x08
127#define S_GCR		0x04
128#define S_COPY_PROT	0x02
129#define S_INV_WDATA	0x01
130
131/* Select values for swim3_action */
132#define SEEK_POSITIVE	0
133#define SEEK_NEGATIVE	4
134#define STEP		1
135#define MOTOR_ON	2
136#define MOTOR_OFF	6
137#define INDEX		3
138#define EJECT		7
139#define SETMFM		9
140#define SETGCR		13
141
142/* Select values for swim3_select and swim3_readbit */
143#define STEP_DIR	0
144#define STEPPING	1
145#define MOTOR_ON	2
146#define RELAX		3	/* also eject in progress */
147#define READ_DATA_0	4
148#define ONEMEG_DRIVE	5
149#define SINGLE_SIDED	6	/* drive or diskette is 4MB type? */
150#define DRIVE_PRESENT	7
151#define DISK_IN		8
152#define WRITE_PROT	9
153#define TRACK_ZERO	10
154#define TACHO		11
155#define READ_DATA_1	12
156#define GCR_MODE	13
157#define SEEK_COMPLETE	14
158#define TWOMEG_MEDIA	15
159
160/* Definitions of values used in writing and formatting */
161#define DATA_ESCAPE	0x99
162#define GCR_SYNC_EXC	0x3f
163#define GCR_SYNC_CONV	0x80
164#define GCR_FIRST_MARK	0xd5
165#define GCR_SECOND_MARK	0xaa
166#define GCR_ADDR_MARK	"\xd5\xaa\x00"
167#define GCR_DATA_MARK	"\xd5\xaa\x0b"
168#define GCR_SLIP_BYTE	"\x27\xaa"
169#define GCR_SELF_SYNC	"\x3f\xbf\x1e\x34\x3c\x3f"
170
171#define DATA_99		"\x99\x99"
172#define MFM_ADDR_MARK	"\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
173#define MFM_INDEX_MARK	"\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
174#define MFM_GAP_LEN	12
175
176struct floppy_state {
177	enum swim_state	state;
178	struct swim3 __iomem *swim3;	/* hardware registers */
179	struct dbdma_regs __iomem *dma;	/* DMA controller registers */
180	int	swim3_intr;	/* interrupt number for SWIM3 */
181	int	dma_intr;	/* interrupt number for DMA channel */
182	int	cur_cyl;	/* cylinder head is on, or -1 */
183	int	cur_sector;	/* last sector we saw go past */
184	int	req_cyl;	/* the cylinder for the current r/w request */
185	int	head;		/* head number ditto */
186	int	req_sector;	/* sector number ditto */
187	int	scount;		/* # sectors we're transferring at present */
188	int	retries;
189	int	settle_time;
190	int	secpercyl;	/* disk geometry information */
191	int	secpertrack;
192	int	total_secs;
193	int	write_prot;	/* 1 if write-protected, 0 if not, -1 dunno */
194	struct dbdma_cmd *dma_cmd;
195	int	ref_count;
196	int	expect_cyl;
197	struct timer_list timeout;
198	int	timeout_pending;
199	int	ejected;
200	wait_queue_head_t wait;
201	int	wanted;
202	struct macio_dev *mdev;
203	char	dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
204	int	index;
205	struct request *cur_req;
206	struct blk_mq_tag_set tag_set;
207};
208
209#define swim3_err(fmt, arg...)	dev_err(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
210#define swim3_warn(fmt, arg...)	dev_warn(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
211#define swim3_info(fmt, arg...)	dev_info(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
212
213#ifdef DEBUG
214#define swim3_dbg(fmt, arg...)	dev_dbg(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
215#else
216#define swim3_dbg(fmt, arg...)	do { } while(0)
217#endif
218
219static struct floppy_state floppy_states[MAX_FLOPPIES];
220static int floppy_count = 0;
221static DEFINE_SPINLOCK(swim3_lock);
222
223static unsigned short write_preamble[] = {
224	0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e,	/* gap field */
225	0, 0, 0, 0, 0, 0,			/* sync field */
226	0x99a1, 0x99a1, 0x99a1, 0x99fb,		/* data address mark */
227	0x990f					/* no escape for 512 bytes */
228};
229
230static unsigned short write_postamble[] = {
231	0x9904,					/* insert CRC */
232	0x4e4e, 0x4e4e,
233	0x9908,					/* stop writing */
234	0, 0, 0, 0, 0, 0
235};
236
237static void seek_track(struct floppy_state *fs, int n);
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, blk_mode_t mode,
250			unsigned int cmd, unsigned long param);
251static int floppy_open(struct gendisk *disk, blk_mode_t mode);
252static unsigned int floppy_check_events(struct gendisk *disk,
253					unsigned int clearing);
254static int floppy_revalidate(struct gendisk *disk);
255
256static bool swim3_end_request(struct floppy_state *fs, blk_status_t err, unsigned int nr_bytes)
257{
258	struct request *req = fs->cur_req;
259
260	swim3_dbg("  end request, err=%d nr_bytes=%d, cur_req=%p\n",
261		  err, nr_bytes, req);
262
263	if (err)
264		nr_bytes = blk_rq_cur_bytes(req);
265	if (blk_update_request(req, err, nr_bytes))
266		return true;
267	__blk_mq_end_request(req, err);
268	fs->cur_req = NULL;
269	return false;
270}
271
272static void swim3_select(struct floppy_state *fs, int sel)
273{
274	struct swim3 __iomem *sw = fs->swim3;
275
276	out_8(&sw->select, RELAX);
277	if (sel & 8)
278		out_8(&sw->control_bis, SELECT);
279	else
280		out_8(&sw->control_bic, SELECT);
281	out_8(&sw->select, sel & CA_MASK);
282}
283
284static void swim3_action(struct floppy_state *fs, int action)
285{
286	struct swim3 __iomem *sw = fs->swim3;
287
288	swim3_select(fs, action);
289	udelay(1);
290	out_8(&sw->select, sw->select | LSTRB);
291	udelay(2);
292	out_8(&sw->select, sw->select & ~LSTRB);
293	udelay(1);
294}
295
296static int swim3_readbit(struct floppy_state *fs, int bit)
297{
298	struct swim3 __iomem *sw = fs->swim3;
299	int stat;
300
301	swim3_select(fs, bit);
302	udelay(1);
303	stat = in_8(&sw->status);
304	return (stat & DATA) == 0;
305}
306
307static blk_status_t swim3_queue_rq(struct blk_mq_hw_ctx *hctx,
308				   const struct blk_mq_queue_data *bd)
309{
310	struct floppy_state *fs = hctx->queue->queuedata;
311	struct request *req = bd->rq;
312	unsigned long x;
313
314	spin_lock_irq(&swim3_lock);
315	if (fs->cur_req || fs->state != idle) {
316		spin_unlock_irq(&swim3_lock);
317		return BLK_STS_DEV_RESOURCE;
318	}
319	blk_mq_start_request(req);
320	fs->cur_req = req;
321	if (fs->mdev->media_bay &&
322	    check_media_bay(fs->mdev->media_bay) != MB_FD) {
323		swim3_dbg("%s", "  media bay absent, dropping req\n");
324		swim3_end_request(fs, BLK_STS_IOERR, 0);
325		goto out;
326	}
327	if (fs->ejected) {
328		swim3_dbg("%s", "  disk ejected\n");
329		swim3_end_request(fs, BLK_STS_IOERR, 0);
330		goto out;
331	}
332	if (rq_data_dir(req) == WRITE) {
333		if (fs->write_prot < 0)
334			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
335		if (fs->write_prot) {
336			swim3_dbg("%s", "  try to write, disk write protected\n");
337			swim3_end_request(fs, BLK_STS_IOERR, 0);
338			goto out;
339		}
340	}
341
342	/*
343	 * Do not remove the cast. blk_rq_pos(req) is now a sector_t and can be
344	 * 64 bits, but it will never go past 32 bits for this driver anyway, so
345	 * we can safely cast it down and not have to do a 64/32 division
346	 */
347	fs->req_cyl = ((long)blk_rq_pos(req)) / fs->secpercyl;
348	x = ((long)blk_rq_pos(req)) % fs->secpercyl;
349	fs->head = x / fs->secpertrack;
350	fs->req_sector = x % fs->secpertrack + 1;
351	fs->state = do_transfer;
352	fs->retries = 0;
353
354	act(fs);
355
356out:
357	spin_unlock_irq(&swim3_lock);
358	return BLK_STS_OK;
359}
360
361static void set_timeout(struct floppy_state *fs, int nticks,
362			void (*proc)(struct timer_list *t))
363{
364	if (fs->timeout_pending)
365		del_timer(&fs->timeout);
366	fs->timeout.expires = jiffies + nticks;
367	fs->timeout.function = proc;
368	add_timer(&fs->timeout);
369	fs->timeout_pending = 1;
370}
371
372static inline void scan_track(struct floppy_state *fs)
373{
374	struct swim3 __iomem *sw = fs->swim3;
375
376	swim3_select(fs, READ_DATA_0);
377	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
378	in_8(&sw->error);
379	out_8(&sw->intr_enable, SEEN_SECTOR);
380	out_8(&sw->control_bis, DO_ACTION);
381	/* enable intr when track found */
382	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
383}
384
385static inline void seek_track(struct floppy_state *fs, int n)
386{
387	struct swim3 __iomem *sw = fs->swim3;
388
389	if (n >= 0) {
390		swim3_action(fs, SEEK_POSITIVE);
391		sw->nseek = n;
392	} else {
393		swim3_action(fs, SEEK_NEGATIVE);
394		sw->nseek = -n;
395	}
396	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
397	swim3_select(fs, STEP);
398	in_8(&sw->error);
399	/* enable intr when seek finished */
400	out_8(&sw->intr_enable, SEEK_DONE);
401	out_8(&sw->control_bis, DO_SEEK);
402	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
403	fs->settle_time = 0;
404}
405
406/*
407 * XXX: this is a horrible hack, but at least allows ppc32 to get
408 * out of defining virt_to_bus, and this driver out of using the
409 * deprecated block layer bounce buffering for highmem addresses
410 * for no good reason.
411 */
412static unsigned long swim3_phys_to_bus(phys_addr_t paddr)
413{
414	return paddr + PCI_DRAM_OFFSET;
415}
416
417static phys_addr_t swim3_bio_phys(struct bio *bio)
418{
419	return page_to_phys(bio_page(bio)) + bio_offset(bio);
420}
421
422static inline void init_dma(struct dbdma_cmd *cp, int cmd,
423			    phys_addr_t paddr, int count)
424{
425	cp->req_count = cpu_to_le16(count);
426	cp->command = cpu_to_le16(cmd);
427	cp->phy_addr = cpu_to_le32(swim3_phys_to_bus(paddr));
428	cp->xfer_status = 0;
429}
430
431static inline void setup_transfer(struct floppy_state *fs)
432{
433	int n;
434	struct swim3 __iomem *sw = fs->swim3;
435	struct dbdma_cmd *cp = fs->dma_cmd;
436	struct dbdma_regs __iomem *dr = fs->dma;
437	struct request *req = fs->cur_req;
438
439	if (blk_rq_cur_sectors(req) <= 0) {
440		swim3_warn("%s", "Transfer 0 sectors ?\n");
441		return;
442	}
443	if (rq_data_dir(req) == WRITE)
444		n = 1;
445	else {
446		n = fs->secpertrack - fs->req_sector + 1;
447		if (n > blk_rq_cur_sectors(req))
448			n = blk_rq_cur_sectors(req);
449	}
450
451	swim3_dbg("  setup xfer at sect %d (of %d) head %d for %d\n",
452		  fs->req_sector, fs->secpertrack, fs->head, n);
453
454	fs->scount = n;
455	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
456	out_8(&sw->sector, fs->req_sector);
457	out_8(&sw->nsect, n);
458	out_8(&sw->gap3, 0);
459	out_le32(&dr->cmdptr, swim3_phys_to_bus(virt_to_phys(cp)));
460	if (rq_data_dir(req) == WRITE) {
461		/* Set up 3 dma commands: write preamble, data, postamble */
462		init_dma(cp, OUTPUT_MORE, virt_to_phys(write_preamble),
463			 sizeof(write_preamble));
464		++cp;
465		init_dma(cp, OUTPUT_MORE, swim3_bio_phys(req->bio), 512);
466		++cp;
467		init_dma(cp, OUTPUT_LAST, virt_to_phys(write_postamble),
468			sizeof(write_postamble));
469	} else {
470		init_dma(cp, INPUT_LAST, swim3_bio_phys(req->bio), n * 512);
471	}
472	++cp;
473	out_le16(&cp->command, DBDMA_STOP);
474	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
475	in_8(&sw->error);
476	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
477	if (rq_data_dir(req) == WRITE)
478		out_8(&sw->control_bis, WRITE_SECTORS);
479	in_8(&sw->intr);
480	out_le32(&dr->control, (RUN << 16) | RUN);
481	/* enable intr when transfer complete */
482	out_8(&sw->intr_enable, TRANSFER_DONE);
483	out_8(&sw->control_bis, DO_ACTION);
484	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
485}
486
487static void act(struct floppy_state *fs)
488{
489	for (;;) {
490		swim3_dbg("  act loop, state=%d, req_cyl=%d, cur_cyl=%d\n",
491			  fs->state, fs->req_cyl, fs->cur_cyl);
492
493		switch (fs->state) {
494		case idle:
495			return;		/* XXX shouldn't get here */
496
497		case locating:
498			if (swim3_readbit(fs, TRACK_ZERO)) {
499				swim3_dbg("%s", "    locate track 0\n");
500				fs->cur_cyl = 0;
501				if (fs->req_cyl == 0)
502					fs->state = do_transfer;
503				else
504					fs->state = seeking;
505				break;
506			}
507			scan_track(fs);
508			return;
509
510		case seeking:
511			if (fs->cur_cyl < 0) {
512				fs->expect_cyl = -1;
513				fs->state = locating;
514				break;
515			}
516			if (fs->req_cyl == fs->cur_cyl) {
517				swim3_warn("%s", "Whoops, seeking 0\n");
518				fs->state = do_transfer;
519				break;
520			}
521			seek_track(fs, fs->req_cyl - fs->cur_cyl);
522			return;
523
524		case settling:
525			/* check for SEEK_COMPLETE after 30ms */
526			fs->settle_time = (HZ + 32) / 33;
527			set_timeout(fs, fs->settle_time, settle_timeout);
528			return;
529
530		case do_transfer:
531			if (fs->cur_cyl != fs->req_cyl) {
532				if (fs->retries > 5) {
533					swim3_err("Wrong cylinder in transfer, want: %d got %d\n",
534						  fs->req_cyl, fs->cur_cyl);
535					swim3_end_request(fs, BLK_STS_IOERR, 0);
536					fs->state = idle;
537					return;
538				}
539				fs->state = seeking;
540				break;
541			}
542			setup_transfer(fs);
543			return;
544
545		case jogging:
546			seek_track(fs, -5);
547			return;
548
549		default:
550			swim3_err("Unknown state %d\n", fs->state);
551			return;
552		}
553	}
554}
555
556static void scan_timeout(struct timer_list *t)
557{
558	struct floppy_state *fs = from_timer(fs, t, timeout);
559	struct swim3 __iomem *sw = fs->swim3;
560	unsigned long flags;
561
562	swim3_dbg("* scan timeout, state=%d\n", fs->state);
563
564	spin_lock_irqsave(&swim3_lock, flags);
565	fs->timeout_pending = 0;
566	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
567	out_8(&sw->select, RELAX);
568	out_8(&sw->intr_enable, 0);
569	fs->cur_cyl = -1;
570	if (fs->retries > 5) {
571		swim3_end_request(fs, BLK_STS_IOERR, 0);
572		fs->state = idle;
573	} else {
574		fs->state = jogging;
575		act(fs);
576	}
577	spin_unlock_irqrestore(&swim3_lock, flags);
578}
579
580static void seek_timeout(struct timer_list *t)
581{
582	struct floppy_state *fs = from_timer(fs, t, timeout);
583	struct swim3 __iomem *sw = fs->swim3;
584	unsigned long flags;
585
586	swim3_dbg("* seek timeout, state=%d\n", fs->state);
587
588	spin_lock_irqsave(&swim3_lock, flags);
589	fs->timeout_pending = 0;
590	out_8(&sw->control_bic, DO_SEEK);
591	out_8(&sw->select, RELAX);
592	out_8(&sw->intr_enable, 0);
593	swim3_err("%s", "Seek timeout\n");
594	swim3_end_request(fs, BLK_STS_IOERR, 0);
595	fs->state = idle;
596	spin_unlock_irqrestore(&swim3_lock, flags);
597}
598
599static void settle_timeout(struct timer_list *t)
600{
601	struct floppy_state *fs = from_timer(fs, t, timeout);
602	struct swim3 __iomem *sw = fs->swim3;
603	unsigned long flags;
604
605	swim3_dbg("* settle timeout, state=%d\n", fs->state);
606
607	spin_lock_irqsave(&swim3_lock, flags);
608	fs->timeout_pending = 0;
609	if (swim3_readbit(fs, SEEK_COMPLETE)) {
610		out_8(&sw->select, RELAX);
611		fs->state = locating;
612		act(fs);
613		goto unlock;
614	}
615	out_8(&sw->select, RELAX);
616	if (fs->settle_time < 2*HZ) {
617		++fs->settle_time;
618		set_timeout(fs, 1, settle_timeout);
619		goto unlock;
620	}
621	swim3_err("%s", "Seek settle timeout\n");
622	swim3_end_request(fs, BLK_STS_IOERR, 0);
623	fs->state = idle;
624 unlock:
625	spin_unlock_irqrestore(&swim3_lock, flags);
626}
627
628static void xfer_timeout(struct timer_list *t)
629{
630	struct floppy_state *fs = from_timer(fs, t, timeout);
631	struct swim3 __iomem *sw = fs->swim3;
632	struct dbdma_regs __iomem *dr = fs->dma;
633	unsigned long flags;
634	int n;
635
636	swim3_dbg("* xfer timeout, state=%d\n", fs->state);
637
638	spin_lock_irqsave(&swim3_lock, flags);
639	fs->timeout_pending = 0;
640	out_le32(&dr->control, RUN << 16);
641	/* We must wait a bit for dbdma to stop */
642	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
643		udelay(1);
644	out_8(&sw->intr_enable, 0);
645	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
646	out_8(&sw->select, RELAX);
647	swim3_err("Timeout %sing sector %ld\n",
648	       (rq_data_dir(fs->cur_req)==WRITE? "writ": "read"),
649	       (long)blk_rq_pos(fs->cur_req));
650	swim3_end_request(fs, BLK_STS_IOERR, 0);
651	fs->state = idle;
652	spin_unlock_irqrestore(&swim3_lock, flags);
653}
654
655static irqreturn_t swim3_interrupt(int irq, void *dev_id)
656{
657	struct floppy_state *fs = (struct floppy_state *) dev_id;
658	struct swim3 __iomem *sw = fs->swim3;
659	int intr, err, n;
660	int stat, resid;
661	struct dbdma_regs __iomem *dr;
662	struct dbdma_cmd *cp;
663	unsigned long flags;
664	struct request *req = fs->cur_req;
665
666	swim3_dbg("* interrupt, state=%d\n", fs->state);
667
668	spin_lock_irqsave(&swim3_lock, flags);
669	intr = in_8(&sw->intr);
670	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
671	if ((intr & ERROR_INTR) && fs->state != do_transfer)
672		swim3_err("Non-transfer error interrupt: state=%d, dir=%x, intr=%x, err=%x\n",
673			  fs->state, rq_data_dir(req), intr, err);
674	switch (fs->state) {
675	case locating:
676		if (intr & SEEN_SECTOR) {
677			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
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 (sw->ctrack == 0xff) {
683				swim3_err("%s", "Seen sector but cyl=ff?\n");
684				fs->cur_cyl = -1;
685				if (fs->retries > 5) {
686					swim3_end_request(fs, BLK_STS_IOERR, 0);
687					fs->state = idle;
688				} else {
689					fs->state = jogging;
690					act(fs);
691				}
692				break;
693			}
694			fs->cur_cyl = sw->ctrack;
695			fs->cur_sector = sw->csect;
696			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
697				swim3_err("Expected cyl %d, got %d\n",
698					  fs->expect_cyl, fs->cur_cyl);
699			fs->state = do_transfer;
700			act(fs);
701		}
702		break;
703	case seeking:
704	case jogging:
705		if (sw->nseek == 0) {
706			out_8(&sw->control_bic, DO_SEEK);
707			out_8(&sw->select, RELAX);
708			out_8(&sw->intr_enable, 0);
709			del_timer(&fs->timeout);
710			fs->timeout_pending = 0;
711			if (fs->state == seeking)
712				++fs->retries;
713			fs->state = settling;
714			act(fs);
715		}
716		break;
717	case settling:
718		out_8(&sw->intr_enable, 0);
719		del_timer(&fs->timeout);
720		fs->timeout_pending = 0;
721		act(fs);
722		break;
723	case do_transfer:
724		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
725			break;
726		out_8(&sw->intr_enable, 0);
727		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
728		out_8(&sw->select, RELAX);
729		del_timer(&fs->timeout);
730		fs->timeout_pending = 0;
731		dr = fs->dma;
732		cp = fs->dma_cmd;
733		if (rq_data_dir(req) == WRITE)
734			++cp;
735		/*
736		 * Check that the main data transfer has finished.
737		 * On writing, the swim3 sometimes doesn't use
738		 * up all the bytes of the postamble, so we can still
739		 * see DMA active here.  That doesn't matter as long
740		 * as all the sector data has been transferred.
741		 */
742		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
743			/* wait a little while for DMA to complete */
744			for (n = 0; n < 100; ++n) {
745				if (cp->xfer_status != 0)
746					break;
747				udelay(1);
748				barrier();
749			}
750		}
751		/* turn off DMA */
752		out_le32(&dr->control, (RUN | PAUSE) << 16);
753		stat = le16_to_cpu(cp->xfer_status);
754		resid = le16_to_cpu(cp->res_count);
755		if (intr & ERROR_INTR) {
756			n = fs->scount - 1 - resid / 512;
757			if (n > 0) {
758				blk_update_request(req, 0, n << 9);
759				fs->req_sector += n;
760			}
761			if (fs->retries < 5) {
762				++fs->retries;
763				act(fs);
764			} else {
765				swim3_err("Error %sing block %ld (err=%x)\n",
766				       rq_data_dir(req) == WRITE? "writ": "read",
767				       (long)blk_rq_pos(req), err);
768				swim3_end_request(fs, BLK_STS_IOERR, 0);
769				fs->state = idle;
770			}
771		} else {
772			if ((stat & ACTIVE) == 0 || resid != 0) {
773				/* musta been an error */
774				swim3_err("fd dma error: stat=%x resid=%d\n", stat, resid);
775				swim3_err("  state=%d, dir=%x, intr=%x, err=%x\n",
776					  fs->state, rq_data_dir(req), intr, err);
777				swim3_end_request(fs, BLK_STS_IOERR, 0);
778				fs->state = idle;
779				break;
780			}
781			fs->retries = 0;
782			if (swim3_end_request(fs, 0, fs->scount << 9)) {
783				fs->req_sector += fs->scount;
784				if (fs->req_sector > fs->secpertrack) {
785					fs->req_sector -= fs->secpertrack;
786					if (++fs->head > 1) {
787						fs->head = 0;
788						++fs->req_cyl;
789					}
790				}
791				act(fs);
792			} else
793				fs->state = idle;
794		}
795		break;
796	default:
797		swim3_err("Don't know what to do in state %d\n", fs->state);
798	}
799	spin_unlock_irqrestore(&swim3_lock, flags);
800	return IRQ_HANDLED;
801}
802
803/*
804static void fd_dma_interrupt(int irq, void *dev_id)
805{
806}
807*/
808
809/* Called under the mutex to grab exclusive access to a drive */
810static int grab_drive(struct floppy_state *fs, enum swim_state state,
811		      int interruptible)
812{
813	unsigned long flags;
814
815	swim3_dbg("%s", "-> grab drive\n");
816
817	spin_lock_irqsave(&swim3_lock, flags);
818	if (fs->state != idle && fs->state != available) {
819		++fs->wanted;
820		/* this will enable irqs in order to sleep */
821		if (!interruptible)
822			wait_event_lock_irq(fs->wait,
823                                        fs->state == available,
824                                        swim3_lock);
825		else if (wait_event_interruptible_lock_irq(fs->wait,
826					fs->state == available,
827					swim3_lock)) {
828			--fs->wanted;
829			spin_unlock_irqrestore(&swim3_lock, flags);
830			return -EINTR;
831		}
832		--fs->wanted;
833	}
834	fs->state = state;
835	spin_unlock_irqrestore(&swim3_lock, flags);
836
837	return 0;
838}
839
840static void release_drive(struct floppy_state *fs)
841{
842	struct request_queue *q = disks[fs->index]->queue;
843	unsigned long flags;
844
845	swim3_dbg("%s", "-> release drive\n");
846
847	spin_lock_irqsave(&swim3_lock, flags);
848	fs->state = idle;
849	spin_unlock_irqrestore(&swim3_lock, flags);
850
851	blk_mq_freeze_queue(q);
852	blk_mq_quiesce_queue(q);
853	blk_mq_unquiesce_queue(q);
854	blk_mq_unfreeze_queue(q);
855}
856
857static int fd_eject(struct floppy_state *fs)
858{
859	int err, n;
860
861	err = grab_drive(fs, ejecting, 1);
862	if (err)
863		return err;
864	swim3_action(fs, EJECT);
865	for (n = 20; n > 0; --n) {
866		if (signal_pending(current)) {
867			err = -EINTR;
868			break;
869		}
870		swim3_select(fs, RELAX);
871		schedule_timeout_interruptible(1);
872		if (swim3_readbit(fs, DISK_IN) == 0)
873			break;
874	}
875	swim3_select(fs, RELAX);
876	udelay(150);
877	fs->ejected = 1;
878	release_drive(fs);
879	return err;
880}
881
882static struct floppy_struct floppy_type =
883	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
884
885static int floppy_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
886			unsigned int cmd, unsigned long param)
887{
888	struct floppy_state *fs = bdev->bd_disk->private_data;
889	int err;
890
891	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
892		return -EPERM;
893
894	if (fs->mdev->media_bay &&
895	    check_media_bay(fs->mdev->media_bay) != MB_FD)
896		return -ENXIO;
897
898	switch (cmd) {
899	case FDEJECT:
900		if (fs->ref_count != 1)
901			return -EBUSY;
902		err = fd_eject(fs);
903		return err;
904	case FDGETPRM:
905	        if (copy_to_user((void __user *) param, &floppy_type,
906				 sizeof(struct floppy_struct)))
907			return -EFAULT;
908		return 0;
909	}
910	return -ENOTTY;
911}
912
913static int floppy_ioctl(struct block_device *bdev, blk_mode_t mode,
914				 unsigned int cmd, unsigned long param)
915{
916	int ret;
917
918	mutex_lock(&swim3_mutex);
919	ret = floppy_locked_ioctl(bdev, mode, cmd, param);
920	mutex_unlock(&swim3_mutex);
921
922	return ret;
923}
924
925static int floppy_open(struct gendisk *disk, blk_mode_t mode)
926{
927	struct floppy_state *fs = disk->private_data;
928	struct swim3 __iomem *sw = fs->swim3;
929	int n, err = 0;
930
931	if (fs->ref_count == 0) {
932		if (fs->mdev->media_bay &&
933		    check_media_bay(fs->mdev->media_bay) != MB_FD)
934			return -ENXIO;
935		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
936		out_8(&sw->control_bic, 0xff);
937		out_8(&sw->mode, 0x95);
938		udelay(10);
939		out_8(&sw->intr_enable, 0);
940		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
941		swim3_action(fs, MOTOR_ON);
942		fs->write_prot = -1;
943		fs->cur_cyl = -1;
944		for (n = 0; n < 2 * HZ; ++n) {
945			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
946				break;
947			if (signal_pending(current)) {
948				err = -EINTR;
949				break;
950			}
951			swim3_select(fs, RELAX);
952			schedule_timeout_interruptible(1);
953		}
954		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
955				 || swim3_readbit(fs, DISK_IN) == 0))
956			err = -ENXIO;
957		swim3_action(fs, SETMFM);
958		swim3_select(fs, RELAX);
959
960	} else if (fs->ref_count == -1 || mode & BLK_OPEN_EXCL)
961		return -EBUSY;
962
963	if (err == 0 && !(mode & BLK_OPEN_NDELAY) &&
964	    (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE))) {
965		if (disk_check_media_change(disk))
966			floppy_revalidate(disk);
967		if (fs->ejected)
968			err = -ENXIO;
969	}
970
971	if (err == 0 && (mode & BLK_OPEN_WRITE)) {
972		if (fs->write_prot < 0)
973			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
974		if (fs->write_prot)
975			err = -EROFS;
976	}
977
978	if (err) {
979		if (fs->ref_count == 0) {
980			swim3_action(fs, MOTOR_OFF);
981			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
982			swim3_select(fs, RELAX);
983		}
984		return err;
985	}
986
987	if (mode & BLK_OPEN_EXCL)
988		fs->ref_count = -1;
989	else
990		++fs->ref_count;
991
992	return 0;
993}
994
995static int floppy_unlocked_open(struct gendisk *disk, blk_mode_t mode)
996{
997	int ret;
998
999	mutex_lock(&swim3_mutex);
1000	ret = floppy_open(disk, mode);
1001	mutex_unlock(&swim3_mutex);
1002
1003	return ret;
1004}
1005
1006static void floppy_release(struct gendisk *disk)
1007{
1008	struct floppy_state *fs = disk->private_data;
1009	struct swim3 __iomem *sw = fs->swim3;
1010
1011	mutex_lock(&swim3_mutex);
1012	if (fs->ref_count > 0)
1013		--fs->ref_count;
1014	else if (fs->ref_count == -1)
1015		fs->ref_count = 0;
1016	if (fs->ref_count == 0) {
1017		swim3_action(fs, MOTOR_OFF);
1018		out_8(&sw->control_bic, 0xff);
1019		swim3_select(fs, RELAX);
1020	}
1021	mutex_unlock(&swim3_mutex);
1022}
1023
1024static unsigned int floppy_check_events(struct gendisk *disk,
1025					unsigned int clearing)
1026{
1027	struct floppy_state *fs = disk->private_data;
1028	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
1029}
1030
1031static int floppy_revalidate(struct gendisk *disk)
1032{
1033	struct floppy_state *fs = disk->private_data;
1034	struct swim3 __iomem *sw;
1035	int ret, n;
1036
1037	if (fs->mdev->media_bay &&
1038	    check_media_bay(fs->mdev->media_bay) != MB_FD)
1039		return -ENXIO;
1040
1041	sw = fs->swim3;
1042	grab_drive(fs, revalidating, 0);
1043	out_8(&sw->intr_enable, 0);
1044	out_8(&sw->control_bis, DRIVE_ENABLE);
1045	swim3_action(fs, MOTOR_ON);	/* necessary? */
1046	fs->write_prot = -1;
1047	fs->cur_cyl = -1;
1048	mdelay(1);
1049	for (n = HZ; n > 0; --n) {
1050		if (swim3_readbit(fs, SEEK_COMPLETE))
1051			break;
1052		if (signal_pending(current))
1053			break;
1054		swim3_select(fs, RELAX);
1055		schedule_timeout_interruptible(1);
1056	}
1057	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
1058		|| swim3_readbit(fs, DISK_IN) == 0;
1059	if (ret)
1060		swim3_action(fs, MOTOR_OFF);
1061	else {
1062		fs->ejected = 0;
1063		swim3_action(fs, SETMFM);
1064	}
1065	swim3_select(fs, RELAX);
1066
1067	release_drive(fs);
1068	return ret;
1069}
1070
1071static const struct block_device_operations floppy_fops = {
1072	.open		= floppy_unlocked_open,
1073	.release	= floppy_release,
1074	.ioctl		= floppy_ioctl,
1075	.check_events	= floppy_check_events,
1076};
1077
1078static const struct blk_mq_ops swim3_mq_ops = {
1079	.queue_rq = swim3_queue_rq,
1080};
1081
1082static void swim3_mb_event(struct macio_dev* mdev, int mb_state)
1083{
1084	struct floppy_state *fs = macio_get_drvdata(mdev);
1085	struct swim3 __iomem *sw;
1086
1087	if (!fs)
1088		return;
1089
1090	sw = fs->swim3;
1091
1092	if (mb_state != MB_FD)
1093		return;
1094
1095	/* Clear state */
1096	out_8(&sw->intr_enable, 0);
1097	in_8(&sw->intr);
1098	in_8(&sw->error);
1099}
1100
1101static int swim3_add_device(struct macio_dev *mdev, int index)
1102{
1103	struct device_node *swim = mdev->ofdev.dev.of_node;
1104	struct floppy_state *fs = &floppy_states[index];
1105	int rc = -EBUSY;
1106
1107	fs->mdev = mdev;
1108	fs->index = index;
1109
1110	/* Check & Request resources */
1111	if (macio_resource_count(mdev) < 2) {
1112		swim3_err("%s", "No address in device-tree\n");
1113		return -ENXIO;
1114	}
1115	if (macio_irq_count(mdev) < 1) {
1116		swim3_err("%s", "No interrupt in device-tree\n");
1117		return -ENXIO;
1118	}
1119	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1120		swim3_err("%s", "Can't request mmio resource\n");
1121		return -EBUSY;
1122	}
1123	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1124		swim3_err("%s", "Can't request dma resource\n");
1125		macio_release_resource(mdev, 0);
1126		return -EBUSY;
1127	}
1128	dev_set_drvdata(&mdev->ofdev.dev, fs);
1129
1130	if (mdev->media_bay == NULL)
1131		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1132
1133	fs->state = idle;
1134	fs->swim3 = (struct swim3 __iomem *)
1135		ioremap(macio_resource_start(mdev, 0), 0x200);
1136	if (fs->swim3 == NULL) {
1137		swim3_err("%s", "Couldn't map mmio registers\n");
1138		rc = -ENOMEM;
1139		goto out_release;
1140	}
1141	fs->dma = (struct dbdma_regs __iomem *)
1142		ioremap(macio_resource_start(mdev, 1), 0x200);
1143	if (fs->dma == NULL) {
1144		swim3_err("%s", "Couldn't map dma registers\n");
1145		iounmap(fs->swim3);
1146		rc = -ENOMEM;
1147		goto out_release;
1148	}
1149	fs->swim3_intr = macio_irq(mdev, 0);
1150	fs->dma_intr = macio_irq(mdev, 1);
1151	fs->cur_cyl = -1;
1152	fs->cur_sector = -1;
1153	fs->secpercyl = 36;
1154	fs->secpertrack = 18;
1155	fs->total_secs = 2880;
1156	init_waitqueue_head(&fs->wait);
1157
1158	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1159	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1160	fs->dma_cmd[1].command = cpu_to_le16(DBDMA_STOP);
1161
1162	if (mdev->media_bay == NULL || check_media_bay(mdev->media_bay) == MB_FD)
1163		swim3_mb_event(mdev, MB_FD);
1164
1165	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1166		swim3_err("%s", "Couldn't request interrupt\n");
1167		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1168		goto out_unmap;
1169	}
1170
1171	timer_setup(&fs->timeout, NULL, 0);
1172
1173	swim3_info("SWIM3 floppy controller %s\n",
1174		mdev->media_bay ? "in media bay" : "");
1175
1176	return 0;
1177
1178 out_unmap:
1179	iounmap(fs->dma);
1180	iounmap(fs->swim3);
1181
1182 out_release:
1183	macio_release_resource(mdev, 0);
1184	macio_release_resource(mdev, 1);
1185
1186	return rc;
1187}
1188
1189static int swim3_attach(struct macio_dev *mdev,
1190			const struct of_device_id *match)
1191{
1192	struct floppy_state *fs;
1193	struct gendisk *disk;
1194	int rc;
1195
1196	if (floppy_count >= MAX_FLOPPIES)
1197		return -ENXIO;
1198
1199	if (floppy_count == 0) {
1200		rc = register_blkdev(FLOPPY_MAJOR, "fd");
1201		if (rc)
1202			return rc;
1203	}
1204
1205	fs = &floppy_states[floppy_count];
1206	memset(fs, 0, sizeof(*fs));
1207
1208	rc = blk_mq_alloc_sq_tag_set(&fs->tag_set, &swim3_mq_ops, 2,
1209			BLK_MQ_F_SHOULD_MERGE);
1210	if (rc)
1211		goto out_unregister;
1212
1213	disk = blk_mq_alloc_disk(&fs->tag_set, NULL, fs);
1214	if (IS_ERR(disk)) {
1215		rc = PTR_ERR(disk);
1216		goto out_free_tag_set;
1217	}
1218
1219	rc = swim3_add_device(mdev, floppy_count);
1220	if (rc)
1221		goto out_cleanup_disk;
1222
1223	disk->major = FLOPPY_MAJOR;
1224	disk->first_minor = floppy_count;
1225	disk->minors = 1;
1226	disk->fops = &floppy_fops;
1227	disk->private_data = fs;
1228	disk->events = DISK_EVENT_MEDIA_CHANGE;
1229	disk->flags |= GENHD_FL_REMOVABLE | GENHD_FL_NO_PART;
1230	sprintf(disk->disk_name, "fd%d", floppy_count);
1231	set_capacity(disk, 2880);
1232	rc = add_disk(disk);
1233	if (rc)
1234		goto out_cleanup_disk;
1235
1236	disks[floppy_count++] = disk;
1237	return 0;
1238
1239out_cleanup_disk:
1240	put_disk(disk);
1241out_free_tag_set:
1242	blk_mq_free_tag_set(&fs->tag_set);
1243out_unregister:
1244	if (floppy_count == 0)
1245		unregister_blkdev(FLOPPY_MAJOR, "fd");
1246	return rc;
1247}
1248
1249static const struct of_device_id swim3_match[] =
1250{
1251	{
1252	.name		= "swim3",
1253	},
1254	{
1255	.compatible	= "ohare-swim3"
1256	},
1257	{
1258	.compatible	= "swim3"
1259	},
1260	{ /* end of list */ }
1261};
1262
1263static struct macio_driver swim3_driver =
1264{
1265	.driver = {
1266		.name 		= "swim3",
1267		.of_match_table	= swim3_match,
1268	},
1269	.probe		= swim3_attach,
1270#ifdef CONFIG_PMAC_MEDIABAY
1271	.mediabay_event	= swim3_mb_event,
1272#endif
1273#if 0
1274	.suspend	= swim3_suspend,
1275	.resume		= swim3_resume,
1276#endif
1277};
1278
1279
1280static int swim3_init(void)
1281{
1282	macio_register_driver(&swim3_driver);
1283	return 0;
1284}
1285
1286module_init(swim3_init)
1287
1288MODULE_LICENSE("GPL");
1289MODULE_AUTHOR("Paul Mackerras");
1290MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);
1291