[PATCH] pktcdvd: documentation update
[linux-2.6] / 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 #include <linux/config.h>
20 #include <linux/stddef.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/timer.h>
24 #include <linux/delay.h>
25 #include <linux/fd.h>
26 #include <linux/ioctl.h>
27 #include <linux/blkdev.h>
28 #include <linux/devfs_fs_kernel.h>
29 #include <linux/interrupt.h>
30 #include <linux/module.h>
31 #include <asm/io.h>
32 #include <asm/dbdma.h>
33 #include <asm/prom.h>
34 #include <asm/uaccess.h>
35 #include <asm/mediabay.h>
36 #include <asm/machdep.h>
37 #include <asm/pmac_feature.h>
38
39 static struct request_queue *swim3_queue;
40 static struct gendisk *disks[2];
41 static struct request *fd_req;
42
43 #define MAX_FLOPPIES    2
44
45 enum swim_state {
46         idle,
47         locating,
48         seeking,
49         settling,
50         do_transfer,
51         jogging,
52         available,
53         revalidating,
54         ejecting
55 };
56
57 #define REG(x)  unsigned char x; char x ## _pad[15];
58
59 /*
60  * The names for these registers mostly represent speculation on my part.
61  * It will be interesting to see how close they are to the names Apple uses.
62  */
63 struct swim3 {
64         REG(data);
65         REG(timer);             /* counts down at 1MHz */
66         REG(error);
67         REG(mode);
68         REG(select);            /* controls CA0, CA1, CA2 and LSTRB signals */
69         REG(setup);
70         REG(control);           /* writing bits clears them */
71         REG(status);            /* writing bits sets them in control */
72         REG(intr);
73         REG(nseek);             /* # tracks to seek */
74         REG(ctrack);            /* current track number */
75         REG(csect);             /* current sector number */
76         REG(gap3);              /* size of gap 3 in track format */
77         REG(sector);            /* sector # to read or write */
78         REG(nsect);             /* # sectors to read or write */
79         REG(intr_enable);
80 };
81
82 #define control_bic     control
83 #define control_bis     status
84
85 /* Bits in select register */
86 #define CA_MASK         7
87 #define LSTRB           8
88
89 /* Bits in control register */
90 #define DO_SEEK         0x80
91 #define FORMAT          0x40
92 #define SELECT          0x20
93 #define WRITE_SECTORS   0x10
94 #define DO_ACTION       0x08
95 #define DRIVE2_ENABLE   0x04
96 #define DRIVE_ENABLE    0x02
97 #define INTR_ENABLE     0x01
98
99 /* Bits in status register */
100 #define FIFO_1BYTE      0x80
101 #define FIFO_2BYTE      0x40
102 #define ERROR           0x20
103 #define DATA            0x08
104 #define RDDATA          0x04
105 #define INTR_PENDING    0x02
106 #define MARK_BYTE       0x01
107
108 /* Bits in intr and intr_enable registers */
109 #define ERROR_INTR      0x20
110 #define DATA_CHANGED    0x10
111 #define TRANSFER_DONE   0x08
112 #define SEEN_SECTOR     0x04
113 #define SEEK_DONE       0x02
114 #define TIMER_DONE      0x01
115
116 /* Bits in error register */
117 #define ERR_DATA_CRC    0x80
118 #define ERR_ADDR_CRC    0x40
119 #define ERR_OVERRUN     0x04
120 #define ERR_UNDERRUN    0x01
121
122 /* Bits in setup register */
123 #define S_SW_RESET      0x80
124 #define S_GCR_WRITE     0x40
125 #define S_IBM_DRIVE     0x20
126 #define S_TEST_MODE     0x10
127 #define S_FCLK_DIV2     0x08
128 #define S_GCR           0x04
129 #define S_COPY_PROT     0x02
130 #define S_INV_WDATA     0x01
131
132 /* Select values for swim3_action */
133 #define SEEK_POSITIVE   0
134 #define SEEK_NEGATIVE   4
135 #define STEP            1
136 #define MOTOR_ON        2
137 #define MOTOR_OFF       6
138 #define INDEX           3
139 #define EJECT           7
140 #define SETMFM          9
141 #define SETGCR          13
142
143 /* Select values for swim3_select and swim3_readbit */
144 #define STEP_DIR        0
145 #define STEPPING        1
146 #define MOTOR_ON        2
147 #define RELAX           3       /* also eject in progress */
148 #define READ_DATA_0     4
149 #define TWOMEG_DRIVE    5
150 #define SINGLE_SIDED    6       /* drive or diskette is 4MB type? */
151 #define DRIVE_PRESENT   7
152 #define DISK_IN         8
153 #define WRITE_PROT      9
154 #define TRACK_ZERO      10
155 #define TACHO           11
156 #define READ_DATA_1     12
157 #define MFM_MODE        13
158 #define SEEK_COMPLETE   14
159 #define ONEMEG_MEDIA    15
160
161 /* Definitions of values used in writing and formatting */
162 #define DATA_ESCAPE     0x99
163 #define GCR_SYNC_EXC    0x3f
164 #define GCR_SYNC_CONV   0x80
165 #define GCR_FIRST_MARK  0xd5
166 #define GCR_SECOND_MARK 0xaa
167 #define GCR_ADDR_MARK   "\xd5\xaa\x00"
168 #define GCR_DATA_MARK   "\xd5\xaa\x0b"
169 #define GCR_SLIP_BYTE   "\x27\xaa"
170 #define GCR_SELF_SYNC   "\x3f\xbf\x1e\x34\x3c\x3f"
171
172 #define DATA_99         "\x99\x99"
173 #define MFM_ADDR_MARK   "\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
174 #define MFM_INDEX_MARK  "\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
175 #define MFM_GAP_LEN     12
176
177 struct floppy_state {
178         enum swim_state state;
179         struct swim3 __iomem *swim3;    /* hardware registers */
180         struct dbdma_regs __iomem *dma; /* DMA controller registers */
181         int     swim3_intr;     /* interrupt number for SWIM3 */
182         int     dma_intr;       /* interrupt number for DMA channel */
183         int     cur_cyl;        /* cylinder head is on, or -1 */
184         int     cur_sector;     /* last sector we saw go past */
185         int     req_cyl;        /* the cylinder for the current r/w request */
186         int     head;           /* head number ditto */
187         int     req_sector;     /* sector number ditto */
188         int     scount;         /* # sectors we're transferring at present */
189         int     retries;
190         int     settle_time;
191         int     secpercyl;      /* disk geometry information */
192         int     secpertrack;
193         int     total_secs;
194         int     write_prot;     /* 1 if write-protected, 0 if not, -1 dunno */
195         struct dbdma_cmd *dma_cmd;
196         int     ref_count;
197         int     expect_cyl;
198         struct timer_list timeout;
199         int     timeout_pending;
200         int     ejected;
201         wait_queue_head_t wait;
202         int     wanted;
203         struct device_node*     media_bay; /* NULL when not in bay */
204         char    dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
205 };
206
207 static struct floppy_state floppy_states[MAX_FLOPPIES];
208 static int floppy_count = 0;
209 static DEFINE_SPINLOCK(swim3_lock);
210
211 static unsigned short write_preamble[] = {
212         0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, /* gap field */
213         0, 0, 0, 0, 0, 0,                       /* sync field */
214         0x99a1, 0x99a1, 0x99a1, 0x99fb,         /* data address mark */
215         0x990f                                  /* no escape for 512 bytes */
216 };
217
218 static unsigned short write_postamble[] = {
219         0x9904,                                 /* insert CRC */
220         0x4e4e, 0x4e4e,
221         0x9908,                                 /* stop writing */
222         0, 0, 0, 0, 0, 0
223 };
224
225 static void swim3_select(struct floppy_state *fs, int sel);
226 static void swim3_action(struct floppy_state *fs, int action);
227 static int swim3_readbit(struct floppy_state *fs, int bit);
228 static void do_fd_request(request_queue_t * q);
229 static void start_request(struct floppy_state *fs);
230 static void set_timeout(struct floppy_state *fs, int nticks,
231                         void (*proc)(unsigned long));
232 static void scan_track(struct floppy_state *fs);
233 static void seek_track(struct floppy_state *fs, int n);
234 static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
235 static void setup_transfer(struct floppy_state *fs);
236 static void act(struct floppy_state *fs);
237 static void scan_timeout(unsigned long data);
238 static void seek_timeout(unsigned long data);
239 static void settle_timeout(unsigned long data);
240 static void xfer_timeout(unsigned long data);
241 static irqreturn_t swim3_interrupt(int irq, void *dev_id, struct pt_regs *regs);
242 /*static void fd_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs);*/
243 static int grab_drive(struct floppy_state *fs, enum swim_state state,
244                       int interruptible);
245 static void release_drive(struct floppy_state *fs);
246 static int fd_eject(struct floppy_state *fs);
247 static int floppy_ioctl(struct inode *inode, struct file *filp,
248                         unsigned int cmd, unsigned long param);
249 static int floppy_open(struct inode *inode, struct file *filp);
250 static int floppy_release(struct inode *inode, struct file *filp);
251 static int floppy_check_change(struct gendisk *disk);
252 static int floppy_revalidate(struct gendisk *disk);
253 static int swim3_add_device(struct device_node *swims);
254 int swim3_init(void);
255
256 #ifndef CONFIG_PMAC_MEDIABAY
257 #define check_media_bay(which, what)    1
258 #endif
259
260 static void swim3_select(struct floppy_state *fs, int sel)
261 {
262         struct swim3 __iomem *sw = fs->swim3;
263
264         out_8(&sw->select, RELAX);
265         if (sel & 8)
266                 out_8(&sw->control_bis, SELECT);
267         else
268                 out_8(&sw->control_bic, SELECT);
269         out_8(&sw->select, sel & CA_MASK);
270 }
271
272 static void swim3_action(struct floppy_state *fs, int action)
273 {
274         struct swim3 __iomem *sw = fs->swim3;
275
276         swim3_select(fs, action);
277         udelay(1);
278         out_8(&sw->select, sw->select | LSTRB);
279         udelay(2);
280         out_8(&sw->select, sw->select & ~LSTRB);
281         udelay(1);
282 }
283
284 static int swim3_readbit(struct floppy_state *fs, int bit)
285 {
286         struct swim3 __iomem *sw = fs->swim3;
287         int stat;
288
289         swim3_select(fs, bit);
290         udelay(1);
291         stat = in_8(&sw->status);
292         return (stat & DATA) == 0;
293 }
294
295 static void do_fd_request(request_queue_t * q)
296 {
297         int i;
298         for(i=0;i<floppy_count;i++)
299         {
300 #ifdef CONFIG_PMAC_MEDIABAY
301                 if (floppy_states[i].media_bay &&
302                         check_media_bay(floppy_states[i].media_bay, MB_FD))
303                         continue;
304 #endif /* CONFIG_PMAC_MEDIABAY */
305                 start_request(&floppy_states[i]);
306         }
307         sti();
308 }
309
310 static void start_request(struct floppy_state *fs)
311 {
312         struct request *req;
313         unsigned long x;
314
315         if (fs->state == idle && fs->wanted) {
316                 fs->state = available;
317                 wake_up(&fs->wait);
318                 return;
319         }
320         while (fs->state == idle && (req = elv_next_request(swim3_queue))) {
321 #if 0
322                 printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
323                        req->rq_disk->disk_name, req->cmd,
324                        (long)req->sector, req->nr_sectors, req->buffer);
325                 printk("           rq_status=%d errors=%d current_nr_sectors=%ld\n",
326                        req->rq_status, req->errors, req->current_nr_sectors);
327 #endif
328
329                 if (req->sector < 0 || req->sector >= fs->total_secs) {
330                         end_request(req, 0);
331                         continue;
332                 }
333                 if (req->current_nr_sectors == 0) {
334                         end_request(req, 1);
335                         continue;
336                 }
337                 if (fs->ejected) {
338                         end_request(req, 0);
339                         continue;
340                 }
341
342                 if (rq_data_dir(req) == WRITE) {
343                         if (fs->write_prot < 0)
344                                 fs->write_prot = swim3_readbit(fs, WRITE_PROT);
345                         if (fs->write_prot) {
346                                 end_request(req, 0);
347                                 continue;
348                         }
349                 }
350
351                 /* Do not remove the cast. req->sector is now a sector_t and
352                  * can be 64 bits, but it will never go past 32 bits for this
353                  * driver anyway, so we can safely cast it down and not have
354                  * to do a 64/32 division
355                  */
356                 fs->req_cyl = ((long)req->sector) / fs->secpercyl;
357                 x = ((long)req->sector) % fs->secpercyl;
358                 fs->head = x / fs->secpertrack;
359                 fs->req_sector = x % fs->secpertrack + 1;
360                 fd_req = req;
361                 fs->state = do_transfer;
362                 fs->retries = 0;
363
364                 act(fs);
365         }
366 }
367
368 static void set_timeout(struct floppy_state *fs, int nticks,
369                         void (*proc)(unsigned long))
370 {
371         unsigned long flags;
372
373         save_flags(flags); cli();
374         if (fs->timeout_pending)
375                 del_timer(&fs->timeout);
376         fs->timeout.expires = jiffies + nticks;
377         fs->timeout.function = proc;
378         fs->timeout.data = (unsigned long) fs;
379         add_timer(&fs->timeout);
380         fs->timeout_pending = 1;
381         restore_flags(flags);
382 }
383
384 static inline void scan_track(struct floppy_state *fs)
385 {
386         struct swim3 __iomem *sw = fs->swim3;
387
388         swim3_select(fs, READ_DATA_0);
389         in_8(&sw->intr);                /* clear SEEN_SECTOR bit */
390         in_8(&sw->error);
391         out_8(&sw->intr_enable, SEEN_SECTOR);
392         out_8(&sw->control_bis, DO_ACTION);
393         /* enable intr when track found */
394         set_timeout(fs, HZ, scan_timeout);      /* enable timeout */
395 }
396
397 static inline void seek_track(struct floppy_state *fs, int n)
398 {
399         struct swim3 __iomem *sw = fs->swim3;
400
401         if (n >= 0) {
402                 swim3_action(fs, SEEK_POSITIVE);
403                 sw->nseek = n;
404         } else {
405                 swim3_action(fs, SEEK_NEGATIVE);
406                 sw->nseek = -n;
407         }
408         fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
409         swim3_select(fs, STEP);
410         in_8(&sw->error);
411         /* enable intr when seek finished */
412         out_8(&sw->intr_enable, SEEK_DONE);
413         out_8(&sw->control_bis, DO_SEEK);
414         set_timeout(fs, 3*HZ, seek_timeout);    /* enable timeout */
415         fs->settle_time = 0;
416 }
417
418 static inline void init_dma(struct dbdma_cmd *cp, int cmd,
419                             void *buf, int count)
420 {
421         st_le16(&cp->req_count, count);
422         st_le16(&cp->command, cmd);
423         st_le32(&cp->phy_addr, virt_to_bus(buf));
424         cp->xfer_status = 0;
425 }
426
427 static inline void setup_transfer(struct floppy_state *fs)
428 {
429         int n;
430         struct swim3 __iomem *sw = fs->swim3;
431         struct dbdma_cmd *cp = fs->dma_cmd;
432         struct dbdma_regs __iomem *dr = fs->dma;
433
434         if (fd_req->current_nr_sectors <= 0) {
435                 printk(KERN_ERR "swim3: transfer 0 sectors?\n");
436                 return;
437         }
438         if (rq_data_dir(fd_req) == WRITE)
439                 n = 1;
440         else {
441                 n = fs->secpertrack - fs->req_sector + 1;
442                 if (n > fd_req->current_nr_sectors)
443                         n = fd_req->current_nr_sectors;
444         }
445         fs->scount = n;
446         swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
447         out_8(&sw->sector, fs->req_sector);
448         out_8(&sw->nsect, n);
449         out_8(&sw->gap3, 0);
450         out_le32(&dr->cmdptr, virt_to_bus(cp));
451         if (rq_data_dir(fd_req) == WRITE) {
452                 /* Set up 3 dma commands: write preamble, data, postamble */
453                 init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
454                 ++cp;
455                 init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
456                 ++cp;
457                 init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
458         } else {
459                 init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
460         }
461         ++cp;
462         out_le16(&cp->command, DBDMA_STOP);
463         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
464         in_8(&sw->error);
465         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
466         if (rq_data_dir(fd_req) == WRITE)
467                 out_8(&sw->control_bis, WRITE_SECTORS);
468         in_8(&sw->intr);
469         out_le32(&dr->control, (RUN << 16) | RUN);
470         /* enable intr when transfer complete */
471         out_8(&sw->intr_enable, TRANSFER_DONE);
472         out_8(&sw->control_bis, DO_ACTION);
473         set_timeout(fs, 2*HZ, xfer_timeout);    /* enable timeout */
474 }
475
476 static void act(struct floppy_state *fs)
477 {
478         for (;;) {
479                 switch (fs->state) {
480                 case idle:
481                         return;         /* XXX shouldn't get here */
482
483                 case locating:
484                         if (swim3_readbit(fs, TRACK_ZERO)) {
485                                 fs->cur_cyl = 0;
486                                 if (fs->req_cyl == 0)
487                                         fs->state = do_transfer;
488                                 else
489                                         fs->state = seeking;
490                                 break;
491                         }
492                         scan_track(fs);
493                         return;
494
495                 case seeking:
496                         if (fs->cur_cyl < 0) {
497                                 fs->expect_cyl = -1;
498                                 fs->state = locating;
499                                 break;
500                         }
501                         if (fs->req_cyl == fs->cur_cyl) {
502                                 printk("whoops, seeking 0\n");
503                                 fs->state = do_transfer;
504                                 break;
505                         }
506                         seek_track(fs, fs->req_cyl - fs->cur_cyl);
507                         return;
508
509                 case settling:
510                         /* check for SEEK_COMPLETE after 30ms */
511                         fs->settle_time = (HZ + 32) / 33;
512                         set_timeout(fs, fs->settle_time, settle_timeout);
513                         return;
514
515                 case do_transfer:
516                         if (fs->cur_cyl != fs->req_cyl) {
517                                 if (fs->retries > 5) {
518                                         end_request(fd_req, 0);
519                                         fs->state = idle;
520                                         return;
521                                 }
522                                 fs->state = seeking;
523                                 break;
524                         }
525                         setup_transfer(fs);
526                         return;
527
528                 case jogging:
529                         seek_track(fs, -5);
530                         return;
531
532                 default:
533                         printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
534                         return;
535                 }
536         }
537 }
538
539 static void scan_timeout(unsigned long data)
540 {
541         struct floppy_state *fs = (struct floppy_state *) data;
542         struct swim3 __iomem *sw = fs->swim3;
543
544         fs->timeout_pending = 0;
545         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
546         out_8(&sw->select, RELAX);
547         out_8(&sw->intr_enable, 0);
548         fs->cur_cyl = -1;
549         if (fs->retries > 5) {
550                 end_request(fd_req, 0);
551                 fs->state = idle;
552                 start_request(fs);
553         } else {
554                 fs->state = jogging;
555                 act(fs);
556         }
557 }
558
559 static void seek_timeout(unsigned long data)
560 {
561         struct floppy_state *fs = (struct floppy_state *) data;
562         struct swim3 __iomem *sw = fs->swim3;
563
564         fs->timeout_pending = 0;
565         out_8(&sw->control_bic, DO_SEEK);
566         out_8(&sw->select, RELAX);
567         out_8(&sw->intr_enable, 0);
568         printk(KERN_ERR "swim3: seek timeout\n");
569         end_request(fd_req, 0);
570         fs->state = idle;
571         start_request(fs);
572 }
573
574 static void settle_timeout(unsigned long data)
575 {
576         struct floppy_state *fs = (struct floppy_state *) data;
577         struct swim3 __iomem *sw = fs->swim3;
578
579         fs->timeout_pending = 0;
580         if (swim3_readbit(fs, SEEK_COMPLETE)) {
581                 out_8(&sw->select, RELAX);
582                 fs->state = locating;
583                 act(fs);
584                 return;
585         }
586         out_8(&sw->select, RELAX);
587         if (fs->settle_time < 2*HZ) {
588                 ++fs->settle_time;
589                 set_timeout(fs, 1, settle_timeout);
590                 return;
591         }
592         printk(KERN_ERR "swim3: seek settle timeout\n");
593         end_request(fd_req, 0);
594         fs->state = idle;
595         start_request(fs);
596 }
597
598 static void xfer_timeout(unsigned long data)
599 {
600         struct floppy_state *fs = (struct floppy_state *) data;
601         struct swim3 __iomem *sw = fs->swim3;
602         struct dbdma_regs __iomem *dr = fs->dma;
603         struct dbdma_cmd *cp = fs->dma_cmd;
604         unsigned long s;
605         int n;
606
607         fs->timeout_pending = 0;
608         out_le32(&dr->control, RUN << 16);
609         /* We must wait a bit for dbdma to stop */
610         for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
611                 udelay(1);
612         out_8(&sw->intr_enable, 0);
613         out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
614         out_8(&sw->select, RELAX);
615         if (rq_data_dir(fd_req) == WRITE)
616                 ++cp;
617         if (ld_le16(&cp->xfer_status) != 0)
618                 s = fs->scount - ((ld_le16(&cp->res_count) + 511) >> 9);
619         else
620                 s = 0;
621         fd_req->sector += s;
622         fd_req->current_nr_sectors -= s;
623         printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
624                (rq_data_dir(fd_req)==WRITE? "writ": "read"), (long)fd_req->sector);
625         end_request(fd_req, 0);
626         fs->state = idle;
627         start_request(fs);
628 }
629
630 static irqreturn_t swim3_interrupt(int irq, void *dev_id, struct pt_regs *regs)
631 {
632         struct floppy_state *fs = (struct floppy_state *) dev_id;
633         struct swim3 __iomem *sw = fs->swim3;
634         int intr, err, n;
635         int stat, resid;
636         struct dbdma_regs __iomem *dr;
637         struct dbdma_cmd *cp;
638
639         intr = in_8(&sw->intr);
640         err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
641         if ((intr & ERROR_INTR) && fs->state != do_transfer)
642                 printk(KERN_ERR "swim3_interrupt, state=%d, dir=%lx, intr=%x, err=%x\n",
643                        fs->state, rq_data_dir(fd_req), intr, err);
644         switch (fs->state) {
645         case locating:
646                 if (intr & SEEN_SECTOR) {
647                         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
648                         out_8(&sw->select, RELAX);
649                         out_8(&sw->intr_enable, 0);
650                         del_timer(&fs->timeout);
651                         fs->timeout_pending = 0;
652                         if (sw->ctrack == 0xff) {
653                                 printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
654                                 fs->cur_cyl = -1;
655                                 if (fs->retries > 5) {
656                                         end_request(fd_req, 0);
657                                         fs->state = idle;
658                                         start_request(fs);
659                                 } else {
660                                         fs->state = jogging;
661                                         act(fs);
662                                 }
663                                 break;
664                         }
665                         fs->cur_cyl = sw->ctrack;
666                         fs->cur_sector = sw->csect;
667                         if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
668                                 printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
669                                        fs->expect_cyl, fs->cur_cyl);
670                         fs->state = do_transfer;
671                         act(fs);
672                 }
673                 break;
674         case seeking:
675         case jogging:
676                 if (sw->nseek == 0) {
677                         out_8(&sw->control_bic, DO_SEEK);
678                         out_8(&sw->select, RELAX);
679                         out_8(&sw->intr_enable, 0);
680                         del_timer(&fs->timeout);
681                         fs->timeout_pending = 0;
682                         if (fs->state == seeking)
683                                 ++fs->retries;
684                         fs->state = settling;
685                         act(fs);
686                 }
687                 break;
688         case settling:
689                 out_8(&sw->intr_enable, 0);
690                 del_timer(&fs->timeout);
691                 fs->timeout_pending = 0;
692                 act(fs);
693                 break;
694         case do_transfer:
695                 if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
696                         break;
697                 out_8(&sw->intr_enable, 0);
698                 out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
699                 out_8(&sw->select, RELAX);
700                 del_timer(&fs->timeout);
701                 fs->timeout_pending = 0;
702                 dr = fs->dma;
703                 cp = fs->dma_cmd;
704                 if (rq_data_dir(fd_req) == WRITE)
705                         ++cp;
706                 /*
707                  * Check that the main data transfer has finished.
708                  * On writing, the swim3 sometimes doesn't use
709                  * up all the bytes of the postamble, so we can still
710                  * see DMA active here.  That doesn't matter as long
711                  * as all the sector data has been transferred.
712                  */
713                 if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
714                         /* wait a little while for DMA to complete */
715                         for (n = 0; n < 100; ++n) {
716                                 if (cp->xfer_status != 0)
717                                         break;
718                                 udelay(1);
719                                 barrier();
720                         }
721                 }
722                 /* turn off DMA */
723                 out_le32(&dr->control, (RUN | PAUSE) << 16);
724                 stat = ld_le16(&cp->xfer_status);
725                 resid = ld_le16(&cp->res_count);
726                 if (intr & ERROR_INTR) {
727                         n = fs->scount - 1 - resid / 512;
728                         if (n > 0) {
729                                 fd_req->sector += n;
730                                 fd_req->current_nr_sectors -= n;
731                                 fd_req->buffer += n * 512;
732                                 fs->req_sector += n;
733                         }
734                         if (fs->retries < 5) {
735                                 ++fs->retries;
736                                 act(fs);
737                         } else {
738                                 printk("swim3: error %sing block %ld (err=%x)\n",
739                                        rq_data_dir(fd_req) == WRITE? "writ": "read",
740                                        (long)fd_req->sector, err);
741                                 end_request(fd_req, 0);
742                                 fs->state = idle;
743                         }
744                 } else {
745                         if ((stat & ACTIVE) == 0 || resid != 0) {
746                                 /* musta been an error */
747                                 printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
748                                 printk(KERN_ERR "  state=%d, dir=%lx, intr=%x, err=%x\n",
749                                        fs->state, rq_data_dir(fd_req), intr, err);
750                                 end_request(fd_req, 0);
751                                 fs->state = idle;
752                                 start_request(fs);
753                                 break;
754                         }
755                         fd_req->sector += fs->scount;
756                         fd_req->current_nr_sectors -= fs->scount;
757                         fd_req->buffer += fs->scount * 512;
758                         if (fd_req->current_nr_sectors <= 0) {
759                                 end_request(fd_req, 1);
760                                 fs->state = idle;
761                         } else {
762                                 fs->req_sector += fs->scount;
763                                 if (fs->req_sector > fs->secpertrack) {
764                                         fs->req_sector -= fs->secpertrack;
765                                         if (++fs->head > 1) {
766                                                 fs->head = 0;
767                                                 ++fs->req_cyl;
768                                         }
769                                 }
770                                 act(fs);
771                         }
772                 }
773                 if (fs->state == idle)
774                         start_request(fs);
775                 break;
776         default:
777                 printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
778         }
779         return IRQ_HANDLED;
780 }
781
782 /*
783 static void fd_dma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
784 {
785 }
786 */
787
788 static int grab_drive(struct floppy_state *fs, enum swim_state state,
789                       int interruptible)
790 {
791         unsigned long flags;
792
793         save_flags(flags);
794         cli();
795         if (fs->state != idle) {
796                 ++fs->wanted;
797                 while (fs->state != available) {
798                         if (interruptible && signal_pending(current)) {
799                                 --fs->wanted;
800                                 restore_flags(flags);
801                                 return -EINTR;
802                         }
803                         interruptible_sleep_on(&fs->wait);
804                 }
805                 --fs->wanted;
806         }
807         fs->state = state;
808         restore_flags(flags);
809         return 0;
810 }
811
812 static void release_drive(struct floppy_state *fs)
813 {
814         unsigned long flags;
815
816         save_flags(flags);
817         cli();
818         fs->state = idle;
819         start_request(fs);
820         restore_flags(flags);
821 }
822
823 static int fd_eject(struct floppy_state *fs)
824 {
825         int err, n;
826
827         err = grab_drive(fs, ejecting, 1);
828         if (err)
829                 return err;
830         swim3_action(fs, EJECT);
831         for (n = 20; n > 0; --n) {
832                 if (signal_pending(current)) {
833                         err = -EINTR;
834                         break;
835                 }
836                 swim3_select(fs, RELAX);
837                 schedule_timeout_interruptible(1);
838                 if (swim3_readbit(fs, DISK_IN) == 0)
839                         break;
840         }
841         swim3_select(fs, RELAX);
842         udelay(150);
843         fs->ejected = 1;
844         release_drive(fs);
845         return err;
846 }
847
848 static struct floppy_struct floppy_type =
849         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };    /*  7 1.44MB 3.5"   */
850
851 static int floppy_ioctl(struct inode *inode, struct file *filp,
852                         unsigned int cmd, unsigned long param)
853 {
854         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
855         int err;
856                 
857         if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
858                 return -EPERM;
859
860 #ifdef CONFIG_PMAC_MEDIABAY
861         if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
862                 return -ENXIO;
863 #endif
864
865         switch (cmd) {
866         case FDEJECT:
867                 if (fs->ref_count != 1)
868                         return -EBUSY;
869                 err = fd_eject(fs);
870                 return err;
871         case FDGETPRM:
872                 if (copy_to_user((void __user *) param, &floppy_type,
873                                  sizeof(struct floppy_struct)))
874                         return -EFAULT;
875                 return 0;
876         }
877         return -ENOTTY;
878 }
879
880 static int floppy_open(struct inode *inode, struct file *filp)
881 {
882         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
883         struct swim3 __iomem *sw = fs->swim3;
884         int n, err = 0;
885
886         if (fs->ref_count == 0) {
887 #ifdef CONFIG_PMAC_MEDIABAY
888                 if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
889                         return -ENXIO;
890 #endif
891                 out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
892                 out_8(&sw->control_bic, 0xff);
893                 out_8(&sw->mode, 0x95);
894                 udelay(10);
895                 out_8(&sw->intr_enable, 0);
896                 out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
897                 swim3_action(fs, MOTOR_ON);
898                 fs->write_prot = -1;
899                 fs->cur_cyl = -1;
900                 for (n = 0; n < 2 * HZ; ++n) {
901                         if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
902                                 break;
903                         if (signal_pending(current)) {
904                                 err = -EINTR;
905                                 break;
906                         }
907                         swim3_select(fs, RELAX);
908                         schedule_timeout_interruptible(1);
909                 }
910                 if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
911                                  || swim3_readbit(fs, DISK_IN) == 0))
912                         err = -ENXIO;
913                 swim3_action(fs, SETMFM);
914                 swim3_select(fs, RELAX);
915
916         } else if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
917                 return -EBUSY;
918
919         if (err == 0 && (filp->f_flags & O_NDELAY) == 0
920             && (filp->f_mode & 3)) {
921                 check_disk_change(inode->i_bdev);
922                 if (fs->ejected)
923                         err = -ENXIO;
924         }
925
926         if (err == 0 && (filp->f_mode & 2)) {
927                 if (fs->write_prot < 0)
928                         fs->write_prot = swim3_readbit(fs, WRITE_PROT);
929                 if (fs->write_prot)
930                         err = -EROFS;
931         }
932
933         if (err) {
934                 if (fs->ref_count == 0) {
935                         swim3_action(fs, MOTOR_OFF);
936                         out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
937                         swim3_select(fs, RELAX);
938                 }
939                 return err;
940         }
941
942         if (filp->f_flags & O_EXCL)
943                 fs->ref_count = -1;
944         else
945                 ++fs->ref_count;
946
947         return 0;
948 }
949
950 static int floppy_release(struct inode *inode, struct file *filp)
951 {
952         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
953         struct swim3 __iomem *sw = fs->swim3;
954         if (fs->ref_count > 0 && --fs->ref_count == 0) {
955                 swim3_action(fs, MOTOR_OFF);
956                 out_8(&sw->control_bic, 0xff);
957                 swim3_select(fs, RELAX);
958         }
959         return 0;
960 }
961
962 static int floppy_check_change(struct gendisk *disk)
963 {
964         struct floppy_state *fs = disk->private_data;
965         return fs->ejected;
966 }
967
968 static int floppy_revalidate(struct gendisk *disk)
969 {
970         struct floppy_state *fs = disk->private_data;
971         struct swim3 __iomem *sw;
972         int ret, n;
973
974 #ifdef CONFIG_PMAC_MEDIABAY
975         if (fs->media_bay && check_media_bay(fs->media_bay, MB_FD))
976                 return -ENXIO;
977 #endif
978
979         sw = fs->swim3;
980         grab_drive(fs, revalidating, 0);
981         out_8(&sw->intr_enable, 0);
982         out_8(&sw->control_bis, DRIVE_ENABLE);
983         swim3_action(fs, MOTOR_ON);     /* necessary? */
984         fs->write_prot = -1;
985         fs->cur_cyl = -1;
986         mdelay(1);
987         for (n = HZ; n > 0; --n) {
988                 if (swim3_readbit(fs, SEEK_COMPLETE))
989                         break;
990                 if (signal_pending(current))
991                         break;
992                 swim3_select(fs, RELAX);
993                 schedule_timeout_interruptible(1);
994         }
995         ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
996                 || swim3_readbit(fs, DISK_IN) == 0;
997         if (ret)
998                 swim3_action(fs, MOTOR_OFF);
999         else {
1000                 fs->ejected = 0;
1001                 swim3_action(fs, SETMFM);
1002         }
1003         swim3_select(fs, RELAX);
1004
1005         release_drive(fs);
1006         return ret;
1007 }
1008
1009 static struct block_device_operations floppy_fops = {
1010         .open           = floppy_open,
1011         .release        = floppy_release,
1012         .ioctl          = floppy_ioctl,
1013         .media_changed  = floppy_check_change,
1014         .revalidate_disk= floppy_revalidate,
1015 };
1016
1017 int swim3_init(void)
1018 {
1019         struct device_node *swim;
1020         int err = -ENOMEM;
1021         int i;
1022
1023         devfs_mk_dir("floppy");
1024
1025         swim = find_devices("floppy");
1026         while (swim && (floppy_count < MAX_FLOPPIES))
1027         {
1028                 swim3_add_device(swim);
1029                 swim = swim->next;
1030         }
1031
1032         swim = find_devices("swim3");
1033         while (swim && (floppy_count < MAX_FLOPPIES))
1034         {
1035                 swim3_add_device(swim);
1036                 swim = swim->next;
1037         }
1038
1039         if (!floppy_count)
1040                 return -ENODEV;
1041
1042         for (i = 0; i < floppy_count; i++) {
1043                 disks[i] = alloc_disk(1);
1044                 if (!disks[i])
1045                         goto out;
1046         }
1047
1048         if (register_blkdev(FLOPPY_MAJOR, "fd")) {
1049                 err = -EBUSY;
1050                 goto out;
1051         }
1052
1053         swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
1054         if (!swim3_queue) {
1055                 err = -ENOMEM;
1056                 goto out_queue;
1057         }
1058
1059         for (i = 0; i < floppy_count; i++) {
1060                 struct gendisk *disk = disks[i];
1061                 disk->major = FLOPPY_MAJOR;
1062                 disk->first_minor = i;
1063                 disk->fops = &floppy_fops;
1064                 disk->private_data = &floppy_states[i];
1065                 disk->queue = swim3_queue;
1066                 disk->flags |= GENHD_FL_REMOVABLE;
1067                 sprintf(disk->disk_name, "fd%d", i);
1068                 sprintf(disk->devfs_name, "floppy/%d", i);
1069                 set_capacity(disk, 2880);
1070                 add_disk(disk);
1071         }
1072         return 0;
1073
1074 out_queue:
1075         unregister_blkdev(FLOPPY_MAJOR, "fd");
1076 out:
1077         while (i--)
1078                 put_disk(disks[i]);
1079         /* shouldn't we do something with results of swim_add_device()? */
1080         return err;
1081 }
1082
1083 static int swim3_add_device(struct device_node *swim)
1084 {
1085         struct device_node *mediabay;
1086         struct floppy_state *fs = &floppy_states[floppy_count];
1087
1088         if (swim->n_addrs < 2)
1089         {
1090                 printk(KERN_INFO "swim3: expecting 2 addrs (n_addrs:%d, n_intrs:%d)\n",
1091                        swim->n_addrs, swim->n_intrs);
1092                 return -EINVAL;
1093         }
1094
1095         if (swim->n_intrs < 2)
1096         {
1097                 printk(KERN_INFO "swim3: expecting 2 intrs (n_addrs:%d, n_intrs:%d)\n",
1098                        swim->n_addrs, swim->n_intrs);
1099                 return -EINVAL;
1100         }
1101
1102         if (!request_OF_resource(swim, 0, NULL)) {
1103                 printk(KERN_INFO "swim3: can't request IO resource !\n");
1104                 return -EINVAL;
1105         }
1106
1107         mediabay = (strcasecmp(swim->parent->type, "media-bay") == 0) ? swim->parent : NULL;
1108         if (mediabay == NULL)
1109                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
1110         
1111         memset(fs, 0, sizeof(*fs));
1112         fs->state = idle;
1113         fs->swim3 = (struct swim3 __iomem *)
1114                 ioremap(swim->addrs[0].address, 0x200);
1115         fs->dma = (struct dbdma_regs __iomem *)
1116                 ioremap(swim->addrs[1].address, 0x200);
1117         fs->swim3_intr = swim->intrs[0].line;
1118         fs->dma_intr = swim->intrs[1].line;
1119         fs->cur_cyl = -1;
1120         fs->cur_sector = -1;
1121         fs->secpercyl = 36;
1122         fs->secpertrack = 18;
1123         fs->total_secs = 2880;
1124         fs->media_bay = mediabay;
1125         init_waitqueue_head(&fs->wait);
1126
1127         fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
1128         memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
1129         st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
1130
1131         if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
1132                 printk(KERN_ERR "Couldn't get irq %d for SWIM3\n", fs->swim3_intr);
1133                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1134                 return -EBUSY;
1135         }
1136 /*
1137         if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
1138                 printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
1139                        fs->dma_intr);
1140                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
1141                 return -EBUSY;
1142         }
1143 */
1144
1145         init_timer(&fs->timeout);
1146
1147         printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
1148                 mediabay ? "in media bay" : "");
1149
1150         floppy_count++;
1151         
1152         return 0;
1153 }
1154
1155 module_init(swim3_init)
1156
1157 MODULE_LICENSE("GPL");
1158 MODULE_AUTHOR("Paul Mackerras");
1159 MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);