File: /usr/src/linux/drivers/block/swim_iop.c
1 /*
2 * Driver for the SWIM (Super Woz Integrated Machine) IOP
3 * floppy controller on the Macintosh IIfx and Quadra 900/950
4 *
5 * Written by Joshua M. Thompson (funaho@jurai.org)
6 * based on the SWIM3 driver (c) 1996 by Paul Mackerras.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * 1999-06-12 (jmt) - Initial implementation.
14 */
15
16 /*
17 * -------------------
18 * Theory of Operation
19 * -------------------
20 *
21 * Since the SWIM IOP is message-driven we implement a simple request queue
22 * system. One outstanding request may be queued at any given time (this is
23 * an IOP limitation); only when that request has completed can a new request
24 * be sent.
25 */
26
27 /* This has to be defined before some of the #includes below */
28
29 #define MAJOR_NR FLOPPY_MAJOR
30
31 #include <linux/stddef.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/timer.h>
35 #include <linux/delay.h>
36 #include <linux/fd.h>
37 #include <linux/blk.h>
38 #include <linux/ioctl.h>
39 #include <asm/io.h>
40 #include <asm/uaccess.h>
41 #include <asm/mac_iop.h>
42 #include <asm/swim_iop.h>
43
44 #define DRIVER_VERSION "Version 0.1 (1999-06-12)"
45
46 #define MAX_FLOPPIES 4
47
48 enum swim_state {
49 idle,
50 available,
51 revalidating,
52 transferring,
53 ejecting
54 };
55
56 struct floppy_state {
57 enum swim_state state;
58 int drive_num; /* device number */
59 int secpercyl; /* disk geometry information */
60 int secpertrack;
61 int total_secs;
62 int write_prot; /* 1 if write-protected, 0 if not, -1 dunno */
63 int ref_count;
64 struct timer_list timeout;
65 int ejected;
66 struct wait_queue *wait;
67 int wanted;
68 int timeout_pending;
69 };
70
71 struct swim_iop_req {
72 int sent;
73 int complete;
74 __u8 command[32];
75 struct floppy_state *fs;
76 void (*done)(struct swim_iop_req *);
77 };
78
79 static struct swim_iop_req *current_req;
80 static int floppy_count;
81
82 static struct floppy_state floppy_states[MAX_FLOPPIES];
83
84 static int floppy_blocksizes[2] = {512,512};
85 static int floppy_sizes[2] = {2880,2880};
86
87 static char *drive_names[7] = {
88 "not installed", /* DRV_NONE */
89 "unknown (1)", /* DRV_UNKNOWN */
90 "a 400K drive", /* DRV_400K */
91 "an 800K drive" /* DRV_800K */
92 "unknown (4)", /* ???? */
93 "an FDHD", /* DRV_FDHD */
94 "unknown (6)", /* ???? */
95 "an Apple HD20" /* DRV_HD20 */
96 };
97
98 int swimiop_init(void);
99 static void swimiop_init_request(struct swim_iop_req *);
100 static int swimiop_send_request(struct swim_iop_req *);
101 static void swimiop_receive(struct iop_msg *, struct pt_regs *);
102 static void swimiop_status_update(int, struct swim_drvstatus *);
103 static int swimiop_eject(struct floppy_state *fs);
104
105 static int floppy_ioctl(struct inode *inode, struct file *filp,
106 unsigned int cmd, unsigned long param);
107 static int floppy_open(struct inode *inode, struct file *filp);
108 static int floppy_release(struct inode *inode, struct file *filp);
109 static int floppy_check_change(kdev_t dev);
110 static int floppy_revalidate(kdev_t dev);
111 static int grab_drive(struct floppy_state *fs, enum swim_state state,
112 int interruptible);
113 static void release_drive(struct floppy_state *fs);
114 static void set_timeout(struct floppy_state *fs, int nticks,
115 void (*proc)(unsigned long));
116 static void fd_request_timeout(unsigned long);
117 static void do_fd_request(request_queue_t * q);
118 static void start_request(struct floppy_state *fs);
119
120 static struct block_device_operations floppy_fops = {
121 open: floppy_open,
122 release: floppy_release,
123 ioctl: floppy_ioctl,
124 check_media_change: floppy_check_change,
125 revalidate: floppy_revalidate,
126 };
127
128 /*
129 * SWIM IOP initialization
130 */
131
132 int swimiop_init(void)
133 {
134 volatile struct swim_iop_req req;
135 struct swimcmd_status *cmd = (struct swimcmd_status *) &req.command[0];
136 struct swim_drvstatus *ds = &cmd->status;
137 struct floppy_state *fs;
138 int i;
139
140 current_req = NULL;
141 floppy_count = 0;
142
143 if (!iop_ism_present) return -ENODEV;
144
145 if (register_blkdev(MAJOR_NR, "fd", &floppy_fops)) {
146 printk(KERN_ERR "SWIM-IOP: Unable to get major %d for floppy\n",
147 MAJOR_NR);
148 return -EBUSY;
149 }
150 blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), DEVICE_REQUEST);
151 blksize_size[MAJOR_NR] = floppy_blocksizes;
152 blk_size[MAJOR_NR] = floppy_sizes;
153
154 printk("SWIM-IOP: %s by Joshua M. Thompson (funaho@jurai.org)\n",
155 DRIVER_VERSION);
156
157 if (iop_listen(SWIM_IOP, SWIM_CHAN, swimiop_receive, "SWIM") != 0) {
158 printk(KERN_ERR "SWIM-IOP: IOP channel already in use; can't initialize.\n");
159 return -EBUSY;
160 }
161
162 printk(KERN_ERR "SWIM_IOP: probing for installed drives.\n");
163
164 for (i = 0 ; i < MAX_FLOPPIES ; i++) {
165 memset(&floppy_states[i], 0, sizeof(struct floppy_state));
166 fs = &floppy_states[floppy_count];
167
168 swimiop_init_request(&req);
169 cmd->code = CMD_STATUS;
170 cmd->drive_num = i + 1;
171 if (swimiop_send_request(&req) != 0) continue;
172 while (!req.complete);
173 if (cmd->error != 0) {
174 printk(KERN_ERR "SWIM-IOP: probe on drive %d returned error %d\n", i, (uint) cmd->error);
175 continue;
176 }
177 if (ds->installed != 0x01) continue;
178 printk("SWIM-IOP: drive %d is %s (%s, %s, %s, %s)\n", i,
179 drive_names[ds->info.type],
180 ds->info.external? "ext" : "int",
181 ds->info.scsi? "scsi" : "floppy",
182 ds->info.fixed? "fixed" : "removable",
183 ds->info.secondary? "secondary" : "primary");
184 swimiop_status_update(floppy_count, ds);
185 fs->state = idle;
186
187 init_timer(&fs->timeout);
188 floppy_count++;
189 }
190 printk("SWIM-IOP: detected %d installed drives.\n", floppy_count);
191
192 do_floppy = NULL;
193
194 return 0;
195 }
196
197 static void swimiop_init_request(struct swim_iop_req *req)
198 {
199 req->sent = 0;
200 req->complete = 0;
201 req->done = NULL;
202 }
203
204 static int swimiop_send_request(struct swim_iop_req *req)
205 {
206 unsigned long cpu_flags;
207 int err;
208
209 /* It's doubtful an interrupt routine would try to send */
210 /* a SWIM request, but I'd rather play it safe here. */
211
212 save_flags(cpu_flags);
213 cli();
214
215 if (current_req != NULL) {
216 restore_flags(cpu_flags);
217 return -ENOMEM;
218 }
219
220 current_req = req;
221
222 /* Interrupts should be back on for iop_send_message() */
223
224 restore_flags(cpu_flags);
225
226 err = iop_send_message(SWIM_IOP, SWIM_CHAN, (void *) req,
227 sizeof(req->command), (__u8 *) &req->command[0],
228 swimiop_receive);
229
230 /* No race condition here; we own current_req at this point */
231
232 if (err) {
233 current_req = NULL;
234 } else {
235 req->sent = 1;
236 }
237 return err;
238 }
239
240 /*
241 * Receive a SWIM message from the IOP.
242 *
243 * This will be called in two cases:
244 *
245 * 1. A message has been successfully sent to the IOP.
246 * 2. An unsolicited message was received from the IOP.
247 */
248
249 void swimiop_receive(struct iop_msg *msg, struct pt_regs *regs)
250 {
251 struct swim_iop_req *req;
252 struct swimmsg_status *sm;
253 struct swim_drvstatus *ds;
254
255 req = current_req;
256
257 switch(msg->status) {
258 case IOP_MSGSTATUS_COMPLETE:
259 memcpy(&req->command[0], &msg->reply[0], sizeof(req->command));
260 req->complete = 1;
261 if (req->done) (*req->done)(req);
262 current_req = NULL;
263 break;
264 case IOP_MSGSTATUS_UNSOL:
265 sm = (struct swimmsg_status *) &msg->message[0];
266 ds = &sm->status;
267 swimiop_status_update(sm->drive_num, ds);
268 iop_complete_message(msg);
269 break;
270 }
271 }
272
273 static void swimiop_status_update(int drive_num, struct swim_drvstatus *ds)
274 {
275 struct floppy_state *fs = &floppy_states[drive_num];
276
277 fs->write_prot = (ds->write_prot == 0x80);
278 if ((ds->disk_in_drive != 0x01) && (ds->disk_in_drive != 0x02)) {
279 fs->ejected = 1;
280 } else {
281 fs->ejected = 0;
282 }
283 switch(ds->info.type) {
284 case DRV_400K:
285 fs->secpercyl = 10;
286 fs->secpertrack = 10;
287 fs->total_secs = 800;
288 break;
289 case DRV_800K:
290 fs->secpercyl = 20;
291 fs->secpertrack = 10;
292 fs->total_secs = 1600;
293 break;
294 case DRV_FDHD:
295 fs->secpercyl = 36;
296 fs->secpertrack = 18;
297 fs->total_secs = 2880;
298 break;
299 default:
300 fs->secpercyl = 0;
301 fs->secpertrack = 0;
302 fs->total_secs = 0;
303 break;
304 }
305 }
306
307 static int swimiop_eject(struct floppy_state *fs)
308 {
309 int err, n;
310 struct swim_iop_req req;
311 struct swimcmd_eject *cmd = (struct swimcmd_eject *) &req.command[0];
312
313 err = grab_drive(fs, ejecting, 1);
314 if (err) return err;
315
316 swimiop_init_request(&req);
317 cmd->code = CMD_EJECT;
318 cmd->drive_num = fs->drive_num;
319 err = swimiop_send_request(&req);
320 if (err) {
321 release_drive(fs);
322 return err;
323 }
324 for (n = 2*HZ; n > 0; --n) {
325 if (req.complete) break;
326 if (signal_pending(current)) {
327 err = -EINTR;
328 break;
329 }
330 current->state = TASK_INTERRUPTIBLE;
331 schedule_timeout(1);
332 }
333 release_drive(fs);
334 return cmd->error;
335 }
336
337 static struct floppy_struct floppy_type =
338 { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL }; /* 7 1.44MB 3.5" */
339
340 static int floppy_ioctl(struct inode *inode, struct file *filp,
341 unsigned int cmd, unsigned long param)
342 {
343 struct floppy_state *fs;
344 int err;
345 int devnum = MINOR(inode->i_rdev);
346
347 if (devnum >= floppy_count)
348 return -ENODEV;
349
350 if ((cmd & 0x80) && !suser())
351 return -EPERM;
352
353 fs = &floppy_states[devnum];
354
355 switch (cmd) {
356 case FDEJECT:
357 if (fs->ref_count != 1)
358 return -EBUSY;
359 err = swimiop_eject(fs);
360 return err;
361 case FDGETPRM:
362 err = copy_to_user((void *) param, (void *) &floppy_type,
363 sizeof(struct floppy_struct));
364 return err;
365 }
366 return -ENOTTY;
367 }
368
369 static int floppy_open(struct inode *inode, struct file *filp)
370 {
371 struct floppy_state *fs;
372 int err;
373 int devnum = MINOR(inode->i_rdev);
374
375 if (devnum >= floppy_count)
376 return -ENODEV;
377 if (filp == 0)
378 return -EIO;
379
380 fs = &floppy_states[devnum];
381 err = 0;
382 if (fs->ref_count == -1 || filp->f_flags & O_EXCL) return -EBUSY;
383
384 if (err == 0 && (filp->f_flags & O_NDELAY) == 0
385 && (filp->f_mode & 3)) {
386 check_disk_change(inode->i_rdev);
387 if (fs->ejected)
388 err = -ENXIO;
389 }
390
391 if (err == 0 && (filp->f_mode & 2)) {
392 if (fs->write_prot)
393 err = -EROFS;
394 }
395
396 if (err) return err;
397
398 if (filp->f_flags & O_EXCL)
399 fs->ref_count = -1;
400 else
401 ++fs->ref_count;
402
403 return 0;
404 }
405
406 static int floppy_release(struct inode *inode, struct file *filp)
407 {
408 struct floppy_state *fs;
409 int devnum = MINOR(inode->i_rdev);
410
411 if (devnum >= floppy_count)
412 return -ENODEV;
413
414 fs = &floppy_states[devnum];
415 if (fs->ref_count > 0) fs->ref_count--;
416 return 0;
417 }
418
419 static int floppy_check_change(kdev_t dev)
420 {
421 struct floppy_state *fs;
422 int devnum = MINOR(dev);
423
424 if (MAJOR(dev) != MAJOR_NR || (devnum >= floppy_count))
425 return 0;
426
427 fs = &floppy_states[devnum];
428 return fs->ejected;
429 }
430
431 static int floppy_revalidate(kdev_t dev)
432 {
433 struct floppy_state *fs;
434 int devnum = MINOR(dev);
435
436 if (MAJOR(dev) != MAJOR_NR || (devnum >= floppy_count))
437 return 0;
438
439 fs = &floppy_states[devnum];
440
441 grab_drive(fs, revalidating, 0);
442 /* yadda, yadda */
443 release_drive(fs);
444
445 return 0;
446 }
447
448 static void floppy_off(unsigned int nr)
449 {
450 }
451
452 static int grab_drive(struct floppy_state *fs, enum swim_state state,
453 int interruptible)
454 {
455 unsigned long flags;
456
457 save_flags(flags);
458 cli();
459 if (fs->state != idle) {
460 ++fs->wanted;
461 while (fs->state != available) {
462 if (interruptible && signal_pending(current)) {
463 --fs->wanted;
464 restore_flags(flags);
465 return -EINTR;
466 }
467 interruptible_sleep_on(&fs->wait);
468 }
469 --fs->wanted;
470 }
471 fs->state = state;
472 restore_flags(flags);
473 return 0;
474 }
475
476 static void release_drive(struct floppy_state *fs)
477 {
478 unsigned long flags;
479
480 save_flags(flags);
481 cli();
482 fs->state = idle;
483 start_request(fs);
484 restore_flags(flags);
485 }
486
487 static void set_timeout(struct floppy_state *fs, int nticks,
488 void (*proc)(unsigned long))
489 {
490 unsigned long flags;
491
492 save_flags(flags); cli();
493 if (fs->timeout_pending)
494 del_timer(&fs->timeout);
495 fs->timeout.expires = jiffies + nticks;
496 fs->timeout.function = proc;
497 fs->timeout.data = (unsigned long) fs;
498 add_timer(&fs->timeout);
499 fs->timeout_pending = 1;
500 restore_flags(flags);
501 }
502
503 static void do_fd_request(request_queue_t * q)
504 {
505 int i;
506
507 for (i = 0 ; i < floppy_count ; i++) {
508 start_request(&floppy_states[i]);
509 }
510 }
511
512 static void fd_request_complete(struct swim_iop_req *req)
513 {
514 struct floppy_state *fs = req->fs;
515 struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req->command[0];
516
517 del_timer(&fs->timeout);
518 fs->timeout_pending = 0;
519 fs->state = idle;
520 if (cmd->error) {
521 printk(KERN_ERR "SWIM-IOP: error %d on read/write request.\n", cmd->error);
522 end_request(0);
523 } else {
524 CURRENT->sector += cmd->num_blocks;
525 CURRENT->current_nr_sectors -= cmd->num_blocks;
526 if (CURRENT->current_nr_sectors <= 0) {
527 end_request(1);
528 return;
529 }
530 }
531 start_request(fs);
532 }
533
534 static void fd_request_timeout(unsigned long data)
535 {
536 struct floppy_state *fs = (struct floppy_state *) data;
537
538 fs->timeout_pending = 0;
539 end_request(0);
540 fs->state = idle;
541 }
542
543 static void start_request(struct floppy_state *fs)
544 {
545 volatile struct swim_iop_req req;
546 struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req.command[0];
547
548 if (fs->state == idle && fs->wanted) {
549 fs->state = available;
550 wake_up(&fs->wait);
551 return;
552 }
553 while (!QUEUE_EMPTY && fs->state == idle) {
554 if (MAJOR(CURRENT->rq_dev) != MAJOR_NR)
555 panic(DEVICE_NAME ": request list destroyed");
556 if (CURRENT->bh && !buffer_locked(CURRENT->bh))
557 panic(DEVICE_NAME ": block not locked");
558 #if 0
559 printk("do_fd_req: dev=%x cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
560 kdev_t_to_nr(CURRENT->rq_dev), CURRENT->cmd,
561 CURRENT->sector, CURRENT->nr_sectors, CURRENT->buffer);
562 printk(" rq_status=%d errors=%d current_nr_sectors=%ld\n",
563 CURRENT->rq_status, CURRENT->errors, CURRENT->current_nr_sectors);
564 #endif
565
566 if (CURRENT->sector < 0 || CURRENT->sector >= fs->total_secs) {
567 end_request(0);
568 continue;
569 }
570 if (CURRENT->current_nr_sectors == 0) {
571 end_request(1);
572 continue;
573 }
574 if (fs->ejected) {
575 end_request(0);
576 continue;
577 }
578
579 swimiop_init_request(&req);
580 req.fs = fs;
581 req.done = fd_request_complete;
582
583 if (CURRENT->cmd == WRITE) {
584 if (fs->write_prot) {
585 end_request(0);
586 continue;
587 }
588 cmd->code = CMD_WRITE;
589 } else {
590 cmd->code = CMD_READ;
591
592 }
593 cmd->drive_num = fs->drive_num;
594 cmd->buffer = CURRENT->buffer;
595 cmd->first_block = CURRENT->sector;
596 cmd->num_blocks = CURRENT->current_nr_sectors;
597
598 if (swimiop_send_request(&req)) {
599 end_request(0);
600 continue;
601 }
602
603 set_timeout(fs, HZ*CURRENT->current_nr_sectors,
604 fd_request_timeout);
605
606 fs->state = transferring;
607 }
608 }
609