block/swim3: Locking fixes
[pandora-kernel.git] / drivers / block / swim3.c
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 #undef DEBUG
20
21 #include <linux/stddef.h>
22 #include <linux/kernel.h>
23 #include <linux/sched.h>
24 #include <linux/timer.h>
25 #include <linux/delay.h>
26 #include <linux/fd.h>
27 #include <linux/ioctl.h>
28 #include <linux/blkdev.h>
29 #include <linux/interrupt.h>
30 #include <linux/mutex.h>
31 #include <linux/module.h>
32 #include <linux/spinlock.h>
33 #include <asm/io.h>
34 #include <asm/dbdma.h>
35 #include <asm/prom.h>
36 #include <asm/uaccess.h>
37 #include <asm/mediabay.h>
38 #include <asm/machdep.h>
39 #include <asm/pmac_feature.h>
40
41 #define MAX_FLOPPIES    2
42
43 static DEFINE_MUTEX(swim3_mutex);
44 static struct gendisk *disks[MAX_FLOPPIES];
45
46 enum swim_state {
47         idle,
48         locating,
49         seeking,
50         settling,
51         do_transfer,
52         jogging,
53         available,
54         revalidating,
55         ejecting
56 };
57
58 #define REG(x)  unsigned char x; char x ## _pad[15];
59
60 /*
61  * The names for these registers mostly represent speculation on my part.
62  * It will be interesting to see how close they are to the names Apple uses.
63  */
64 struct swim3 {
65         REG(data);
66         REG(timer);             /* counts down at 1MHz */
67         REG(error);
68         REG(mode);
69         REG(select);            /* controls CA0, CA1, CA2 and LSTRB signals */
70         REG(setup);
71         REG(control);           /* writing bits clears them */
72         REG(status);            /* writing bits sets them in control */
73         REG(intr);
74         REG(nseek);             /* # tracks to seek */
75         REG(ctrack);            /* current track number */
76         REG(csect);             /* current sector number */
77         REG(gap3);              /* size of gap 3 in track format */
78         REG(sector);            /* sector # to read or write */
79         REG(nsect);             /* # sectors to read or write */
80         REG(intr_enable);
81 };
82
83 #define control_bic     control
84 #define control_bis     status
85
86 /* Bits in select register */
87 #define CA_MASK         7
88 #define LSTRB           8
89
90 /* Bits in control register */
91 #define DO_SEEK         0x80
92 #define FORMAT          0x40
93 #define SELECT          0x20
94 #define WRITE_SECTORS   0x10
95 #define DO_ACTION       0x08
96 #define DRIVE2_ENABLE   0x04
97 #define DRIVE_ENABLE    0x02
98 #define INTR_ENABLE     0x01
99
100 /* Bits in status register */
101 #define FIFO_1BYTE      0x80
102 #define FIFO_2BYTE      0x40
103 #define ERROR           0x20
104 #define DATA            0x08
105 #define RDDATA          0x04
106 #define INTR_PENDING    0x02
107 #define MARK_BYTE       0x01
108
109 /* Bits in intr and intr_enable registers */
110 #define ERROR_INTR      0x20
111 #define DATA_CHANGED    0x10
112 #define TRANSFER_DONE   0x08
113 #define SEEN_SECTOR     0x04
114 #define SEEK_DONE       0x02
115 #define TIMER_DONE      0x01
116
117 /* Bits in error register */
118 #define ERR_DATA_CRC    0x80
119 #define ERR_ADDR_CRC    0x40
120 #define ERR_OVERRUN     0x04
121 #define ERR_UNDERRUN    0x01
122
123 /* Bits in setup register */
124 #define S_SW_RESET      0x80
125 #define S_GCR_WRITE     0x40
126 #define S_IBM_DRIVE     0x20
127 #define S_TEST_MODE     0x10
128 #define S_FCLK_DIV2     0x08
129 #define S_GCR           0x04
130 #define S_COPY_PROT     0x02
131 #define S_INV_WDATA     0x01
132
133 /* Select values for swim3_action */
134 #define SEEK_POSITIVE   0
135 #define SEEK_NEGATIVE   4
136 #define STEP            1
137 #define MOTOR_ON        2
138 #define MOTOR_OFF       6
139 #define INDEX           3
140 #define EJECT           7
141 #define SETMFM          9
142 #define SETGCR          13
143
144 /* Select values for swim3_select and swim3_readbit */
145 #define STEP_DIR        0
146 #define STEPPING        1
147 #define MOTOR_ON        2
148 #define RELAX           3       /* also eject in progress */
149 #define READ_DATA_0     4
150 #define TWOMEG_DRIVE    5
151 #define SINGLE_SIDED    6       /* drive or diskette is 4MB type? */
152 #define DRIVE_PRESENT   7
153 #define DISK_IN         8
154 #define WRITE_PROT      9
155 #define TRACK_ZERO      10
156 #define TACHO           11
157 #define READ_DATA_1     12
158 #define MFM_MODE        13
159 #define SEEK_COMPLETE   14
160 #define ONEMEG_MEDIA    15
161
162 /* Definitions of values used in writing and formatting */
163 #define DATA_ESCAPE     0x99
164 #define GCR_SYNC_EXC    0x3f
165 #define GCR_SYNC_CONV   0x80
166 #define GCR_FIRST_MARK  0xd5
167 #define GCR_SECOND_MARK 0xaa
168 #define GCR_ADDR_MARK   "\xd5\xaa\x00"
169 #define GCR_DATA_MARK   "\xd5\xaa\x0b"
170 #define GCR_SLIP_BYTE   "\x27\xaa"
171 #define GCR_SELF_SYNC   "\x3f\xbf\x1e\x34\x3c\x3f"
172
173 #define DATA_99         "\x99\x99"
174 #define MFM_ADDR_MARK   "\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
175 #define MFM_INDEX_MARK  "\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
176 #define MFM_GAP_LEN     12
177
178 struct floppy_state {
179         enum swim_state state;
180         struct swim3 __iomem *swim3;    /* hardware registers */
181         struct dbdma_regs __iomem *dma; /* DMA controller registers */
182         int     swim3_intr;     /* interrupt number for SWIM3 */
183         int     dma_intr;       /* interrupt number for DMA channel */
184         int     cur_cyl;        /* cylinder head is on, or -1 */
185         int     cur_sector;     /* last sector we saw go past */
186         int     req_cyl;        /* the cylinder for the current r/w request */
187         int     head;           /* head number ditto */
188         int     req_sector;     /* sector number ditto */
189         int     scount;         /* # sectors we're transferring at present */
190         int     retries;
191         int     settle_time;
192         int     secpercyl;      /* disk geometry information */
193         int     secpertrack;
194         int     total_secs;
195         int     write_prot;     /* 1 if write-protected, 0 if not, -1 dunno */
196         struct dbdma_cmd *dma_cmd;
197         int     ref_count;
198         int     expect_cyl;
199         struct timer_list timeout;
200         int     timeout_pending;
201         int     ejected;
202         wait_queue_head_t wait;
203         int     wanted;
204         struct macio_dev *mdev;
205         char    dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
206         int     index;
207         struct request *cur_req;
208 };
209
210 #define swim3_err(fmt, arg...)  dev_err(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
211 #define swim3_warn(fmt, arg...) dev_warn(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
212 #define swim3_info(fmt, arg...) dev_info(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
213
214 #ifdef DEBUG
215 #define swim3_dbg(fmt, arg...)  dev_dbg(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
216 #else
217 #define swim3_dbg(fmt, arg...)  do { } while(0)
218 #endif
219
220 static struct floppy_state floppy_states[MAX_FLOPPIES];
221 static int floppy_count = 0;
222 static DEFINE_SPINLOCK(swim3_lock);
223
224 static unsigned short write_preamble[] = {
225         0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, /* gap field */
226         0, 0, 0, 0, 0, 0,                       /* sync field */
227         0x99a1, 0x99a1, 0x99a1, 0x99fb,         /* data address mark */
228         0x990f                                  /* no escape for 512 bytes */
229 };
230
231 static unsigned short write_postamble[] = {
232         0x9904,                                 /* insert CRC */
233         0x4e4e, 0x4e4e,
234         0x9908,                                 /* stop writing */
235         0, 0, 0, 0, 0, 0
236 };
237
238 static void seek_track(struct floppy_state *fs, int n);
239 static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
240 static void act(struct floppy_state *fs);
241 static void scan_timeout(unsigned long data);
242 static void seek_timeout(unsigned long data);
243 static void settle_timeout(unsigned long data);
244 static void xfer_timeout(unsigned long data);
245 static irqreturn_t swim3_interrupt(int irq, void *dev_id);
246 /*static void fd_dma_interrupt(int irq, void *dev_id);*/
247 static int grab_drive(struct floppy_state *fs, enum swim_state state,
248                       int interruptible);
249 static void release_drive(struct floppy_state *fs);
250 static int fd_eject(struct floppy_state *fs);
251 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
252                         unsigned int cmd, unsigned long param);
253 static int floppy_open(struct block_device *bdev, fmode_t mode);
254 static int floppy_release(struct gendisk *disk, fmode_t mode);
255 static unsigned int floppy_check_events(struct gendisk *disk,
256                                         unsigned int clearing);
257 static int floppy_revalidate(struct gendisk *disk);
258
259 static bool swim3_end_request(struct floppy_state *fs, int err, unsigned int nr_bytes)
260 {
261         struct request *req = fs->cur_req;
262         int rc;
263
264         swim3_dbg("  end request, err=%d nr_bytes=%d, cur_req=%p\n",
265                   err, nr_bytes, req);
266
267         if (err)
268                 nr_bytes = blk_rq_cur_bytes(req);
269         rc = __blk_end_request(req, err, nr_bytes);
270         if (rc)
271                 return true;
272         fs->cur_req = NULL;
273         return false;
274 }
275
276 static void swim3_select(struct floppy_state *fs, int sel)
277 {
278         struct swim3 __iomem *sw = fs->swim3;
279
280         out_8(&sw->select, RELAX);
281         if (sel & 8)
282                 out_8(&sw->control_bis, SELECT);
283         else
284                 out_8(&sw->control_bic, SELECT);
285         out_8(&sw->select, sel & CA_MASK);
286 }
287
288 static void swim3_action(struct floppy_state *fs, int action)
289 {
290         struct swim3 __iomem *sw = fs->swim3;
291
292         swim3_select(fs, action);
293         udelay(1);
294         out_8(&sw->select, sw->select | LSTRB);
295         udelay(2);
296         out_8(&sw->select, sw->select & ~LSTRB);
297         udelay(1);
298 }
299
300 static int swim3_readbit(struct floppy_state *fs, int bit)
301 {
302         struct swim3 __iomem *sw = fs->swim3;
303         int stat;
304
305         swim3_select(fs, bit);
306         udelay(1);
307         stat = in_8(&sw->status);
308         return (stat & DATA) == 0;
309 }
310
311 static void start_request(struct floppy_state *fs)
312 {
313         struct request *req;
314         unsigned long x;
315
316         swim3_dbg("start request, initial state=%d\n", fs->state);
317
318         if (fs->state == idle && fs->wanted) {
319                 fs->state = available;
320                 wake_up(&fs->wait);
321                 return;
322         }
323         while (fs->state == idle) {
324                 swim3_dbg("start request, idle loop, cur_req=%p\n", fs->cur_req);
325                 if (!fs->cur_req) {
326                         fs->cur_req = blk_fetch_request(disks[fs->index]->queue);
327                         swim3_dbg("  fetched request %p\n", fs->cur_req);
328                         if (!fs->cur_req)
329                                 break;
330                 }
331                 req = fs->cur_req;
332
333                 if (fs->mdev->media_bay &&
334                     check_media_bay(fs->mdev->media_bay) != MB_FD) {
335                         swim3_dbg("%s", "  media bay absent, dropping req\n");
336                         swim3_end_request(fs, -ENODEV, 0);
337                         continue;
338                 }
339
340 #if 0 /* This is really too verbose */
341                 swim3_dbg("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%u buf=%p\n",
342                           req->rq_disk->disk_name, req->cmd,
343                           (long)blk_rq_pos(req), blk_rq_sectors(req),
344                           req->buffer);
345                 swim3_dbg("           errors=%d current_nr_sectors=%u\n",
346                           req->errors, blk_rq_cur_sectors(req));
347 #endif
348
349                 if (blk_rq_pos(req) >= fs->total_secs) {
350                         swim3_dbg("  pos out of bounds (%ld, max is %ld)\n",
351                                   (long)blk_rq_pos(req), (long)fs->total_secs);
352                         swim3_end_request(fs, -EIO, 0);
353                         continue;
354                 }
355                 if (fs->ejected) {
356                         swim3_dbg("%s", "  disk ejected\n");
357                         swim3_end_request(fs, -EIO, 0);
358                         continue;
359                 }
360
361                 if (rq_data_dir(req) == WRITE) {
362                         if (fs->write_prot < 0)
363                                 fs->write_prot = swim3_readbit(fs, WRITE_PROT);
364                         if (fs->write_prot) {
365                                 swim3_dbg("%s", "  try to write, disk write protected\n");
366                                 swim3_end_request(fs, -EIO, 0);
367                                 continue;
368                         }
369                 }
370
371                 /* Do not remove the cast. blk_rq_pos(req) is now a
372                  * sector_t and can be 64 bits, but it will never go
373                  * past 32 bits for this driver anyway, so we can
374                  * safely cast it down and not have to do a 64/32
375                  * division
376                  */
377                 fs->req_cyl = ((long)blk_rq_pos(req)) / fs->secpercyl;
378                 x = ((long)blk_rq_pos(req)) % fs->secpercyl;
379                 fs->head = x / fs->secpertrack;
380                 fs->req_sector = x % fs->secpertrack + 1;
381                 fs->state = do_transfer;
382                 fs->retries = 0;
383
384                 act(fs);
385         }
386 }
387
388 static void do_fd_request(struct request_queue * q)
389 {
390         start_request(q->queuedata);
391 }
392
393 static void set_timeout(struct floppy_state *fs, int nticks,
394                         void (*proc)(unsigned long))
395 {
396         if (fs->timeout_pending)
397                 del_timer(&fs->timeout);
398         fs->timeout.expires = jiffies + nticks;
399         fs->timeout.function = proc;
400         fs->timeout.data = (unsigned long) fs;
401         add_timer(&fs->timeout);
402         fs->timeout_pending = 1;
403 }
404
405 static inline void scan_track(struct floppy_state *fs)
406 {
407         struct swim3 __iomem *sw = fs->swim3;
408
409         swim3_select(fs, READ_DATA_0);
410         in_8(&sw->intr);                /* clear SEEN_SECTOR bit */
411         in_8(&sw->error);
412         out_8(&sw->intr_enable, SEEN_SECTOR);
413         out_8(&sw->control_bis, DO_ACTION);
414         /* enable intr when track found */
415         set_timeout(fs, HZ, scan_timeout);      /* enable timeout */
416 }
417
418 static inline void seek_track(struct floppy_state *fs, int n)
419 {
420         struct swim3 __iomem *sw = fs->swim3;
421
422         if (n >= 0) {
423                 swim3_action(fs, SEEK_POSITIVE);
424                 sw->nseek = n;
425         } else {
426                 swim3_action(fs, SEEK_NEGATIVE);
427                 sw->nseek = -n;
428         }
429         fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
430         swim3_select(fs, STEP);
431         in_8(&sw->error);
432         /* enable intr when seek finished */
433         out_8(&sw->intr_enable, SEEK_DONE);
434         out_8(&sw->control_bis, DO_SEEK);
435         set_timeout(fs, 3*HZ, seek_timeout);    /* enable timeout */
436         fs->settle_time = 0;
437 }
438
439 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
440                             void *buf, int count)
441 {
442         st_le16(&cp->req_count, count);
443         st_le16(&cp->command, cmd);
444         st_le32(&cp->phy_addr, virt_to_bus(buf));
445         cp->xfer_status = 0;
446 }
447
448 static inline void setup_transfer(struct floppy_state *fs)
449 {
450         int n;
451         struct swim3 __iomem *sw = fs->swim3;
452         struct dbdma_cmd *cp = fs->dma_cmd;
453         struct dbdma_regs __iomem *dr = fs->dma;
454         struct request *req = fs->cur_req;
455
456         if (blk_rq_cur_sectors(req) <= 0) {
457                 swim3_warn("%s", "Transfer 0 sectors ?\n");
458                 return;
459         }
460         if (rq_data_dir(req) == WRITE)
461                 n = 1;
462         else {
463                 n = fs->secpertrack - fs->req_sector + 1;
464                 if (n > blk_rq_cur_sectors(req))
465                         n = blk_rq_cur_sectors(req);
466         }
467
468         swim3_dbg("  setup xfer at sect %d (of %d) head %d for %d\n",
469                   fs->req_sector, fs->secpertrack, fs->head, n);
470
471         fs->scount = n;
472         swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
473         out_8(&sw->sector, fs->req_sector);
474         out_8(&sw->nsect, n);
475         out_8(&sw->gap3, 0);
476         out_le32(&dr->cmdptr, virt_to_bus(cp));
477         if (rq_data_dir(req) == WRITE) {
478                 /* Set up 3 dma commands: write preamble, data, postamble */
479                 init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
480                 ++cp;
481                 init_dma(cp, OUTPUT_MORE, req->buffer, 512);
482                 ++cp;
483                 init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
484         } else {
485                 init_dma(cp, INPUT_LAST, req->buffer, n * 512);
486         }
487         ++cp;
488         out_le16(&cp->command, DBDMA_STOP);
489         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
490         in_8(&sw->error);
491         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
492         if (rq_data_dir(req) == WRITE)
493                 out_8(&sw->control_bis, WRITE_SECTORS);
494         in_8(&sw->intr);
495         out_le32(&dr->control, (RUN << 16) | RUN);
496         /* enable intr when transfer complete */
497         out_8(&sw->intr_enable, TRANSFER_DONE);
498         out_8(&sw->control_bis, DO_ACTION);
499         set_timeout(fs, 2*HZ, xfer_timeout);    /* enable timeout */
500 }
501
502 static void act(struct floppy_state *fs)
503 {
504         for (;;) {
505                 swim3_dbg("  act loop, state=%d, req_cyl=%d, cur_cyl=%d\n",
506                           fs->state, fs->req_cyl, fs->cur_cyl);
507
508                 switch (fs->state) {
509                 case idle:
510                         return;         /* XXX shouldn't get here */
511
512                 case locating:
513                         if (swim3_readbit(fs, TRACK_ZERO)) {
514                                 swim3_dbg("%s", "    locate track 0\n");
515                                 fs->cur_cyl = 0;
516                                 if (fs->req_cyl == 0)
517                                         fs->state = do_transfer;
518                                 else
519                                         fs->state = seeking;
520                                 break;
521                         }
522                         scan_track(fs);
523                         return;
524
525                 case seeking:
526                         if (fs->cur_cyl < 0) {
527                                 fs->expect_cyl = -1;
528                                 fs->state = locating;
529                                 break;
530                         }
531                         if (fs->req_cyl == fs->cur_cyl) {
532                                 swim3_warn("%s", "Whoops, seeking 0\n");
533                                 fs->state = do_transfer;
534                                 break;
535                         }
536                         seek_track(fs, fs->req_cyl - fs->cur_cyl);
537                         return;
538
539                 case settling:
540                         /* check for SEEK_COMPLETE after 30ms */
541                         fs->settle_time = (HZ + 32) / 33;
542                         set_timeout(fs, fs->settle_time, settle_timeout);
543                         return;
544
545                 case do_transfer:
546                         if (fs->cur_cyl != fs->req_cyl) {
547                                 if (fs->retries > 5) {
548                                         swim3_err("Wrong cylinder in transfer, want: %d got %d\n",
549                                                   fs->req_cyl, fs->cur_cyl);
550                                         swim3_end_request(fs, -EIO, 0);
551                                         fs->state = idle;
552                                         return;
553                                 }
554                                 fs->state = seeking;
555                                 break;
556                         }
557                         setup_transfer(fs);
558                         return;
559
560                 case jogging:
561                         seek_track(fs, -5);
562                         return;
563
564                 default:
565                         swim3_err("Unknown state %d\n", fs->state);
566                         return;
567                 }
568         }
569 }
570
571 static void scan_timeout(unsigned long data)
572 {
573         struct floppy_state *fs = (struct floppy_state *) data;
574         struct swim3 __iomem *sw = fs->swim3;
575         unsigned long flags;
576
577         swim3_dbg("* scan timeout, state=%d\n", fs->state);
578
579         spin_lock_irqsave(&swim3_lock, flags);
580         fs->timeout_pending = 0;
581         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
582         out_8(&sw->select, RELAX);
583         out_8(&sw->intr_enable, 0);
584         fs->cur_cyl = -1;
585         if (fs->retries > 5) {
586                 swim3_end_request(fs, -EIO, 0);
587                 fs->state = idle;
588                 start_request(fs);
589         } else {
590                 fs->state = jogging;
591                 act(fs);
592         }
593         spin_unlock_irqrestore(&swim3_lock, flags);
594 }
595
596 static void seek_timeout(unsigned long data)
597 {
598         struct floppy_state *fs = (struct floppy_state *) data;
599         struct swim3 __iomem *sw = fs->swim3;
600         unsigned long flags;
601
602         swim3_dbg("* seek timeout, state=%d\n", fs->state);
603
604         spin_lock_irqsave(&swim3_lock, flags);
605         fs->timeout_pending = 0;
606         out_8(&sw->control_bic, DO_SEEK);
607         out_8(&sw->select, RELAX);
608         out_8(&sw->intr_enable, 0);
609         swim3_err("%s", "Seek timeout\n");
610         swim3_end_request(fs, -EIO, 0);
611         fs->state = idle;
612         start_request(fs);
613         spin_unlock_irqrestore(&swim3_lock, flags);
614 }
615
616 static void settle_timeout(unsigned long data)
617 {
618         struct floppy_state *fs = (struct floppy_state *) data;
619         struct swim3 __iomem *sw = fs->swim3;
620         unsigned long flags;
621
622         swim3_dbg("* settle timeout, state=%d\n", fs->state);
623
624         spin_lock_irqsave(&swim3_lock, flags);
625         fs->timeout_pending = 0;
626         if (swim3_readbit(fs, SEEK_COMPLETE)) {
627                 out_8(&sw->select, RELAX);
628                 fs->state = locating;
629                 act(fs);
630                 goto unlock;
631         }
632         out_8(&sw->select, RELAX);
633         if (fs->settle_time < 2*HZ) {
634                 ++fs->settle_time;
635                 set_timeout(fs, 1, settle_timeout);
636                 goto unlock;
637         }
638         swim3_err("%s", "Seek settle timeout\n");
639         swim3_end_request(fs, -EIO, 0);
640         fs->state = idle;
641         start_request(fs);
642  unlock:
643         spin_unlock_irqrestore(&swim3_lock, flags);
644 }
645
646 static void xfer_timeout(unsigned long data)
647 {
648         struct floppy_state *fs = (struct floppy_state *) data;
649         struct swim3 __iomem *sw = fs->swim3;
650         struct dbdma_regs __iomem *dr = fs->dma;
651         unsigned long flags;
652         int n;
653
654         swim3_dbg("* xfer timeout, state=%d\n", fs->state);
655
656         spin_lock_irqsave(&swim3_lock, flags);
657         fs->timeout_pending = 0;
658         out_le32(&dr->control, RUN << 16);
659         /* We must wait a bit for dbdma to stop */
660         for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
661                 udelay(1);
662         out_8(&sw->intr_enable, 0);
663         out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
664         out_8(&sw->select, RELAX);
665         swim3_err("Timeout %sing sector %ld\n",
666                (rq_data_dir(fs->cur_req)==WRITE? "writ": "read"),
667                (long)blk_rq_pos(fs->cur_req));
668         swim3_end_request(fs, -EIO, 0);
669         fs->state = idle;
670         start_request(fs);
671         spin_unlock_irqrestore(&swim3_lock, flags);
672 }
673
674 static irqreturn_t swim3_interrupt(int irq, void *dev_id)
675 {
676         struct floppy_state *fs = (struct floppy_state *) dev_id;
677         struct swim3 __iomem *sw = fs->swim3;
678         int intr, err, n;
679         int stat, resid;
680         struct dbdma_regs __iomem *dr;
681         struct dbdma_cmd *cp;
682         unsigned long flags;
683         struct request *req = fs->cur_req;
684
685         swim3_dbg("* interrupt, state=%d\n", fs->state);
686
687         spin_lock_irqsave(&swim3_lock, flags);
688         intr = in_8(&sw->intr);
689         err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
690         if ((intr & ERROR_INTR) && fs->state != do_transfer)
691                 swim3_err("Non-transfer error interrupt: state=%d, dir=%x, intr=%x, err=%x\n",
692                           fs->state, rq_data_dir(req), intr, err);
693         switch (fs->state) {
694         case locating:
695                 if (intr & SEEN_SECTOR) {
696                         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
697                         out_8(&sw->select, RELAX);
698                         out_8(&sw->intr_enable, 0);
699                         del_timer(&fs->timeout);
700                         fs->timeout_pending = 0;
701                         if (sw->ctrack == 0xff) {
702                                 swim3_err("%s", "Seen sector but cyl=ff?\n");
703                                 fs->cur_cyl = -1;
704                                 if (fs->retries > 5) {
705                                         swim3_end_request(fs, -EIO, 0);
706                                         fs->state = idle;
707                                         start_request(fs);
708                                 } else {
709                                         fs->state = jogging;
710                                         act(fs);
711                                 }
712                                 break;
713                         }
714                         fs->cur_cyl = sw->ctrack;
715                         fs->cur_sector = sw->csect;
716                         if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
717                                 swim3_err("Expected cyl %d, got %d\n",
718                                           fs->expect_cyl, fs->cur_cyl);
719                         fs->state = do_transfer;
720                         act(fs);
721                 }
722                 break;
723         case seeking:
724         case jogging:
725                 if (sw->nseek == 0) {
726                         out_8(&sw->control_bic, DO_SEEK);
727                         out_8(&sw->select, RELAX);
728                         out_8(&sw->intr_enable, 0);
729                         del_timer(&fs->timeout);
730                         fs->timeout_pending = 0;
731                         if (fs->state == seeking)
732                                 ++fs->retries;
733                         fs->state = settling;
734                         act(fs);
735                 }
736                 break;
737         case settling:
738                 out_8(&sw->intr_enable, 0);
739                 del_timer(&fs->timeout);
740                 fs->timeout_pending = 0;
741                 act(fs);
742                 break;
743         case do_transfer:
744                 if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
745                         break;
746                 out_8(&sw->intr_enable, 0);
747                 out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
748                 out_8(&sw->select, RELAX);
749                 del_timer(&fs->timeout);
750                 fs->timeout_pending = 0;
751                 dr = fs->dma;
752                 cp = fs->dma_cmd;
753                 if (rq_data_dir(req) == WRITE)
754                         ++cp;
755                 /*
756                  * Check that the main data transfer has finished.
757                  * On writing, the swim3 sometimes doesn't use
758                  * up all the bytes of the postamble, so we can still
759                  * see DMA active here.  That doesn't matter as long
760                  * as all the sector data has been transferred.
761                  */
762                 if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
763                         /* wait a little while for DMA to complete */
764                         for (n = 0; n < 100; ++n) {
765                                 if (cp->xfer_status != 0)
766                                         break;
767                                 udelay(1);
768                                 barrier();
769                         }
770                 }
771                 /* turn off DMA */
772                 out_le32(&dr->control, (RUN | PAUSE) << 16);
773                 stat = ld_le16(&cp->xfer_status);
774                 resid = ld_le16(&cp->res_count);
775                 if (intr & ERROR_INTR) {
776                         n = fs->scount - 1 - resid / 512;
777                         if (n > 0) {
778                                 blk_update_request(req, 0, n << 9);
779                                 fs->req_sector += n;
780                         }
781                         if (fs->retries < 5) {
782                                 ++fs->retries;
783                                 act(fs);
784                         } else {
785                                 swim3_err("Error %sing block %ld (err=%x)\n",
786                                        rq_data_dir(req) == WRITE? "writ": "read",
787                                        (long)blk_rq_pos(req), err);
788                                 swim3_end_request(fs, -EIO, 0);
789                                 fs->state = idle;
790                         }
791                 } else {
792                         if ((stat & ACTIVE) == 0 || resid != 0) {
793                                 /* musta been an error */
794                                 swim3_err("fd dma error: stat=%x resid=%d\n", stat, resid);
795                                 swim3_err("  state=%d, dir=%x, intr=%x, err=%x\n",
796                                           fs->state, rq_data_dir(req), intr, err);
797                                 swim3_end_request(fs, -EIO, 0);
798                                 fs->state = idle;
799                                 start_request(fs);
800                                 break;
801                         }
802                         fs->retries = 0;
803                         if (swim3_end_request(fs, 0, fs->scount << 9)) {
804                                 fs->req_sector += fs->scount;
805                                 if (fs->req_sector > fs->secpertrack) {
806                                         fs->req_sector -= fs->secpertrack;
807                                         if (++fs->head > 1) {
808                                                 fs->head = 0;
809                                                 ++fs->req_cyl;
810                                         }
811                                 }
812                                 act(fs);
813                         } else
814                                 fs->state = idle;
815                 }
816                 if (fs->state == idle)
817                         start_request(fs);
818                 break;
819         default:
820                 swim3_err("Don't know what to do in state %d\n", fs->state);
821         }
822         spin_unlock_irqrestore(&swim3_lock, flags);
823         return IRQ_HANDLED;
824 }
825
826 /*
827 static void fd_dma_interrupt(int irq, void *dev_id)
828 {
829 }
830 */
831
832 /* Called under the mutex to grab exclusive access to a drive */
833 static int grab_drive(struct floppy_state *fs, enum swim_state state,
834                       int interruptible)
835 {
836         unsigned long flags;
837
838         swim3_dbg("%s", "-> grab drive\n");
839
840         spin_lock_irqsave(&swim3_lock, flags);
841         if (fs->state != idle && fs->state != available) {
842                 ++fs->wanted;
843                 while (fs->state != available) {
844                         spin_unlock_irqrestore(&swim3_lock, flags);
845                         if (interruptible && signal_pending(current)) {
846                                 --fs->wanted;
847                                 return -EINTR;
848                         }
849                         interruptible_sleep_on(&fs->wait);
850                         spin_lock_irqsave(&swim3_lock, flags);
851                 }
852                 --fs->wanted;
853         }
854         fs->state = state;
855         spin_unlock_irqrestore(&swim3_lock, flags);
856
857         return 0;
858 }
859
860 static void release_drive(struct floppy_state *fs)
861 {
862         unsigned long flags;
863
864         swim3_dbg("%s", "-> release drive\n");
865
866         spin_lock_irqsave(&swim3_lock, flags);
867         fs->state = idle;
868         start_request(fs);
869         spin_unlock_irqrestore(&swim3_lock, flags);
870 }
871
872 static int fd_eject(struct floppy_state *fs)
873 {
874         int err, n;
875
876         err = grab_drive(fs, ejecting, 1);
877         if (err)
878                 return err;
879         swim3_action(fs, EJECT);
880         for (n = 20; n > 0; --n) {
881                 if (signal_pending(current)) {
882                         err = -EINTR;
883                         break;
884                 }
885                 swim3_select(fs, RELAX);
886                 schedule_timeout_interruptible(1);
887                 if (swim3_readbit(fs, DISK_IN) == 0)
888                         break;
889         }
890         swim3_select(fs, RELAX);
891         udelay(150);
892         fs->ejected = 1;
893         release_drive(fs);
894         return err;
895 }
896
897 static struct floppy_struct floppy_type =
898         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };    /*  7 1.44MB 3.5"   */
899
900 static int floppy_locked_ioctl(struct block_device *bdev, fmode_t mode,
901                         unsigned int cmd, unsigned long param)
902 {
903         struct floppy_state *fs = bdev->bd_disk->private_data;
904         int err;
905                 
906         if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
907                 return -EPERM;
908
909         if (fs->mdev->media_bay &&
910             check_media_bay(fs->mdev->media_bay) != MB_FD)
911                 return -ENXIO;
912
913         switch (cmd) {
914         case FDEJECT:
915                 if (fs->ref_count != 1)
916                         return -EBUSY;
917                 err = fd_eject(fs);
918                 return err;
919         case FDGETPRM:
920                 if (copy_to_user((void __user *) param, &floppy_type,
921                                  sizeof(struct floppy_struct)))
922                         return -EFAULT;
923                 return 0;
924         }
925         return -ENOTTY;
926 }
927
928 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
929                                  unsigned int cmd, unsigned long param)
930 {
931         int ret;
932
933         mutex_lock(&swim3_mutex);
934         ret = floppy_locked_ioctl(bdev, mode, cmd, param);
935         mutex_unlock(&swim3_mutex);
936
937         return ret;
938 }
939
940 static int floppy_open(struct block_device *bdev, fmode_t mode)
941 {
942         struct floppy_state *fs = bdev->bd_disk->private_data;
943         struct swim3 __iomem *sw = fs->swim3;
944         int n, err = 0;
945
946         if (fs->ref_count == 0) {
947                 if (fs->mdev->media_bay &&
948                     check_media_bay(fs->mdev->media_bay) != MB_FD)
949                         return -ENXIO;
950                 out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
951                 out_8(&sw->control_bic, 0xff);
952                 out_8(&sw->mode, 0x95);
953                 udelay(10);
954                 out_8(&sw->intr_enable, 0);
955                 out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
956                 swim3_action(fs, MOTOR_ON);
957                 fs->write_prot = -1;
958                 fs->cur_cyl = -1;
959                 for (n = 0; n < 2 * HZ; ++n) {
960                         if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
961                                 break;
962                         if (signal_pending(current)) {
963                                 err = -EINTR;
964                                 break;
965                         }
966                         swim3_select(fs, RELAX);
967                         schedule_timeout_interruptible(1);
968                 }
969                 if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
970                                  || swim3_readbit(fs, DISK_IN) == 0))
971                         err = -ENXIO;
972                 swim3_action(fs, SETMFM);
973                 swim3_select(fs, RELAX);
974
975         } else if (fs->ref_count == -1 || mode & FMODE_EXCL)
976                 return -EBUSY;
977
978         if (err == 0 && (mode & FMODE_NDELAY) == 0
979             && (mode & (FMODE_READ|FMODE_WRITE))) {
980                 check_disk_change(bdev);
981                 if (fs->ejected)
982                         err = -ENXIO;
983         }
984
985         if (err == 0 && (mode & FMODE_WRITE)) {
986                 if (fs->write_prot < 0)
987                         fs->write_prot = swim3_readbit(fs, WRITE_PROT);
988                 if (fs->write_prot)
989                         err = -EROFS;
990         }
991
992         if (err) {
993                 if (fs->ref_count == 0) {
994                         swim3_action(fs, MOTOR_OFF);
995                         out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
996                         swim3_select(fs, RELAX);
997                 }
998                 return err;
999         }
1000
1001         if (mode & FMODE_EXCL)
1002                 fs->ref_count = -1;
1003         else
1004                 ++fs->ref_count;
1005
1006         return 0;
1007 }
1008
1009 static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
1010 {
1011         int ret;
1012
1013         mutex_lock(&swim3_mutex);
1014         ret = floppy_open(bdev, mode);
1015         mutex_unlock(&swim3_mutex);
1016
1017         return ret;
1018 }
1019
1020 static int floppy_release(struct gendisk *disk, fmode_t mode)
1021 {
1022         struct floppy_state *fs = disk->private_data;
1023         struct swim3 __iomem *sw = fs->swim3;
1024
1025         mutex_lock(&swim3_mutex);
1026         if (fs->ref_count > 0 && --fs->ref_count == 0) {
1027                 swim3_action(fs, MOTOR_OFF);
1028                 out_8(&sw->control_bic, 0xff);
1029                 swim3_select(fs, RELAX);
1030         }
1031         mutex_unlock(&swim3_mutex);
1032         return 0;
1033 }
1034
1035 static unsigned int floppy_check_events(struct gendisk *disk,
1036                                         unsigned int clearing)
1037 {
1038         struct floppy_state *fs = disk->private_data;
1039         return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
1040 }
1041
1042 static int floppy_revalidate(struct gendisk *disk)
1043 {
1044         struct floppy_state *fs = disk->private_data;
1045         struct swim3 __iomem *sw;
1046         int ret, n;
1047
1048         if (fs->mdev->media_bay &&
1049             check_media_bay(fs->mdev->media_bay) != MB_FD)
1050                 return -ENXIO;
1051
1052         sw = fs->swim3;
1053         grab_drive(fs, revalidating, 0);
1054         out_8(&sw->intr_enable, 0);
1055         out_8(&sw->control_bis, DRIVE_ENABLE);
1056         swim3_action(fs, MOTOR_ON);     /* necessary? */
1057         fs->write_prot = -1;
1058         fs->cur_cyl = -1;
1059         mdelay(1);
1060         for (n = HZ; n > 0; --n) {
1061                 if (swim3_readbit(fs, SEEK_COMPLETE))
1062                         break;
1063                 if (signal_pending(current))
1064                         break;
1065                 swim3_select(fs, RELAX);
1066                 schedule_timeout_interruptible(1);
1067         }
1068         ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
1069                 || swim3_readbit(fs, DISK_IN) == 0;
1070         if (ret)
1071                 swim3_action(fs, MOTOR_OFF);
1072         else {
1073                 fs->ejected = 0;
1074                 swim3_action(fs, SETMFM);
1075         }
1076         swim3_select(fs, RELAX);
1077
1078         release_drive(fs);
1079         return ret;
1080 }
1081
1082 static const struct block_device_operations floppy_fops = {
1083         .open           = floppy_unlocked_open,
1084         .release        = floppy_release,
1085         .ioctl          = floppy_ioctl,
1086         .check_events   = floppy_check_events,
1087         .revalidate_disk= floppy_revalidate,
1088 };
1089
1090 static void swim3_mb_event(struct macio_dev* mdev, int mb_state)
1091 {
1092         struct floppy_state *fs = macio_get_drvdata(mdev);
1093         struct swim3 __iomem *sw = fs->swim3;
1094
1095         if (!fs)
1096                 return;
1097         if (mb_state != MB_FD)
1098                 return;
1099
1100         /* Clear state */
1101         out_8(&sw->intr_enable, 0);
1102         in_8(&sw->intr);
1103         in_8(&sw->error);
1104 }
1105
1106 static int swim3_add_device(struct macio_dev *mdev, int index)
1107 {
1108         struct device_node *swim = mdev->ofdev.dev.of_node;
1109         struct floppy_state *fs = &floppy_states[index];
1110         int rc = -EBUSY;
1111
1112         /* Do this first for message macros */
1113         memset(fs, 0, sizeof(*fs));
1114         fs->mdev = mdev;
1115         fs->index = index;
1116
1117         /* Check & Request resources */
1118         if (macio_resource_count(mdev) < 2) {
1119                 swim3_err("%s", "No address in device-tree\n");
1120                 return -ENXIO;
1121         }
1122         if (macio_irq_count(mdev) < 1) {
1123                 swim3_err("%s", "No interrupt in device-tree\n");
1124                 return -ENXIO;
1125         }
1126         if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
1127                 swim3_err("%s", "Can't request mmio resource\n");
1128                 return -EBUSY;
1129         }
1130         if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
1131                 swim3_err("%s", "Can't request dma resource\n");
1132                 macio_release_resource(mdev, 0);
1133                 return -EBUSY;
1134         }
1135         dev_set_drvdata(&mdev->ofdev.dev, fs);
1136
1137         if (mdev->media_bay == NULL)
1138                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1139         
1140         fs->state = idle;
1141         fs->swim3 = (struct swim3 __iomem *)
1142                 ioremap(macio_resource_start(mdev, 0), 0x200);
1143         if (fs->swim3 == NULL) {
1144                 swim3_err("%s", "Couldn't map mmio registers\n");
1145                 rc = -ENOMEM;
1146                 goto out_release;
1147         }
1148         fs->dma = (struct dbdma_regs __iomem *)
1149                 ioremap(macio_resource_start(mdev, 1), 0x200);
1150         if (fs->dma == NULL) {
1151                 swim3_err("%s", "Couldn't map dma registers\n");
1152                 iounmap(fs->swim3);
1153                 rc = -ENOMEM;
1154                 goto out_release;
1155         }
1156         fs->swim3_intr = macio_irq(mdev, 0);
1157         fs->dma_intr = macio_irq(mdev, 1);
1158         fs->cur_cyl = -1;
1159         fs->cur_sector = -1;
1160         fs->secpercyl = 36;
1161         fs->secpertrack = 18;
1162         fs->total_secs = 2880;
1163         init_waitqueue_head(&fs->wait);
1164
1165         fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1166         memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1167         st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1168
1169         if (mdev->media_bay == NULL || check_media_bay(mdev->media_bay) == MB_FD)
1170                 swim3_mb_event(mdev, MB_FD);
1171
1172         if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1173                 swim3_err("%s", "Couldn't request interrupt\n");
1174                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1175                 goto out_unmap;
1176                 return -EBUSY;
1177         }
1178
1179         init_timer(&fs->timeout);
1180
1181         swim3_info("SWIM3 floppy controller %s\n",
1182                 mdev->media_bay ? "in media bay" : "");
1183
1184         return 0;
1185
1186  out_unmap:
1187         iounmap(fs->dma);
1188         iounmap(fs->swim3);
1189
1190  out_release:
1191         macio_release_resource(mdev, 0);
1192         macio_release_resource(mdev, 1);
1193
1194         return rc;
1195 }
1196
1197 static int __devinit swim3_attach(struct macio_dev *mdev, const struct of_device_id *match)
1198 {
1199         struct gendisk *disk;
1200         int index, rc;
1201
1202         index = floppy_count++;
1203         if (index >= MAX_FLOPPIES)
1204                 return -ENXIO;
1205
1206         /* Add the drive */
1207         rc = swim3_add_device(mdev, index);
1208         if (rc)
1209                 return rc;
1210         /* Now register that disk. Same comment about failure handling */
1211         disk = disks[index] = alloc_disk(1);
1212         if (disk == NULL)
1213                 return -ENOMEM;
1214         disk->queue = blk_init_queue(do_fd_request, &swim3_lock);
1215         if (disk->queue == NULL) {
1216                 put_disk(disk);
1217                 return -ENOMEM;
1218         }
1219         disk->queue->queuedata = &floppy_states[index];
1220
1221         if (index == 0) {
1222                 /* If we failed, there isn't much we can do as the driver is still
1223                  * too dumb to remove the device, just bail out
1224                  */
1225                 if (register_blkdev(FLOPPY_MAJOR, "fd"))
1226                         return 0;
1227         }
1228
1229         disk->major = FLOPPY_MAJOR;
1230         disk->first_minor = index;
1231         disk->fops = &floppy_fops;
1232         disk->private_data = &floppy_states[index];
1233         disk->flags |= GENHD_FL_REMOVABLE;
1234         sprintf(disk->disk_name, "fd%d", index);
1235         set_capacity(disk, 2880);
1236         add_disk(disk);
1237
1238         return 0;
1239 }
1240
1241 static struct of_device_id swim3_match[] =
1242 {
1243         {
1244         .name           = "swim3",
1245         },
1246         {
1247         .compatible     = "ohare-swim3"
1248         },
1249         {
1250         .compatible     = "swim3"
1251         },
1252         { /* end of list */ }
1253 };
1254
1255 static struct macio_driver swim3_driver =
1256 {
1257         .driver = {
1258                 .name           = "swim3",
1259                 .of_match_table = swim3_match,
1260         },
1261         .probe          = swim3_attach,
1262 #ifdef CONFIG_PMAC_MEDIABAY
1263         .mediabay_event = swim3_mb_event,
1264 #endif
1265 #if 0
1266         .suspend        = swim3_suspend,
1267         .resume         = swim3_resume,
1268 #endif
1269 };
1270
1271
1272 int swim3_init(void)
1273 {
1274         macio_register_driver(&swim3_driver);
1275         return 0;
1276 }
1277
1278 module_init(swim3_init)
1279
1280 MODULE_LICENSE("GPL");
1281 MODULE_AUTHOR("Paul Mackerras");
1282 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);