summaryrefslogtreecommitdiffstats
path: root/drivers/block/swim_iop.c
blob: a1283f6dc0189e1ee0d3d7b0622ea875f2333b5d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
/*
 * Driver for the SWIM (Super Woz Integrated Machine) IOP
 * floppy controller on the Macintosh IIfx and Quadra 900/950
 *
 * Written by Joshua M. Thompson (funaho@jurai.org)
 * based on the SWIM3 driver (c) 1996 by Paul Mackerras.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * 1999-06-12 (jmt) - Initial implementation.
 */

/*
 * -------------------
 * Theory of Operation
 * -------------------
 *
 * Since the SWIM IOP is message-driven we implement a simple request queue
 * system.  One outstanding request may be queued at any given time (this is
 * an IOP limitation); only when that request has completed can a new request
 * be sent.
 */

#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/fd.h>
#include <linux/ioctl.h>
#include <linux/blkdev.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/mac_iop.h>
#include <asm/swim_iop.h>

#define DRIVER_VERSION "Version 0.1 (1999-06-12)"

#define MAX_FLOPPIES	4

enum swim_state {
	idle,
	available,
	revalidating,
	transferring,
	ejecting
};

struct floppy_state {
	enum swim_state state;
	int	drive_num;	/* device number */
	int	secpercyl;	/* disk geometry information */
	int	secpertrack;
	int	total_secs;
	int	write_prot;	/* 1 if write-protected, 0 if not, -1 dunno */
	int	ref_count;
	struct timer_list timeout;
	int	ejected;
	struct wait_queue *wait;
	int	wanted;
	int	timeout_pending;
};

struct swim_iop_req {
	int	sent;
	int	complete;
	__u8	command[32];
	struct floppy_state *fs;
	void	(*done)(struct swim_iop_req *);
};

static struct swim_iop_req *current_req;
static int floppy_count;

static struct floppy_state floppy_states[MAX_FLOPPIES];
static DEFINE_SPINLOCK(swim_iop_lock);

#define CURRENT elv_next_request(swim_queue)

static char *drive_names[7] = {
	"not installed",	/* DRV_NONE    */
	"unknown (1)",		/* DRV_UNKNOWN */
	"a 400K drive",		/* DRV_400K    */
	"an 800K drive"		/* DRV_800K    */
	"unknown (4)",		/* ????        */
	"an FDHD",		/* DRV_FDHD    */
	"unknown (6)",		/* ????        */
	"an Apple HD20"		/* DRV_HD20    */
};

int swimiop_init(void);
static void swimiop_init_request(struct swim_iop_req *);
static int swimiop_send_request(struct swim_iop_req *);
static void swimiop_receive(struct iop_msg *, struct pt_regs *);
static void swimiop_status_update(int, struct swim_drvstatus *);
static int swimiop_eject(struct floppy_state *fs);

static int floppy_ioctl(struct inode *inode, struct file *filp,
			unsigned int cmd, unsigned long param);
static int floppy_open(struct inode *inode, struct file *filp);
static int floppy_release(struct inode *inode, struct file *filp);
static int floppy_check_change(struct gendisk *disk);
static int floppy_revalidate(struct gendisk *disk);
static int grab_drive(struct floppy_state *fs, enum swim_state state,
		      int interruptible);
static void release_drive(struct floppy_state *fs);
static void set_timeout(struct floppy_state *fs, int nticks,
			void (*proc)(unsigned long));
static void fd_request_timeout(unsigned long);
static void do_fd_request(request_queue_t * q);
static void start_request(struct floppy_state *fs);

static struct block_device_operations floppy_fops = {
	.open		= floppy_open,
	.release	= floppy_release,
	.ioctl		= floppy_ioctl,
	.media_changed	= floppy_check_change,
	.revalidate_disk= floppy_revalidate,
};

static struct request_queue *swim_queue;
/*
 * SWIM IOP initialization
 */

int swimiop_init(void)
{
	volatile struct swim_iop_req req;
	struct swimcmd_status *cmd = (struct swimcmd_status *) &req.command[0];
	struct swim_drvstatus *ds = &cmd->status;
	struct floppy_state *fs;
	int i;

	current_req = NULL;
	floppy_count = 0;

	if (!iop_ism_present)
		return -ENODEV;

	if (register_blkdev(FLOPPY_MAJOR, "fd"))
		return -EBUSY;

	swim_queue = blk_init_queue(do_fd_request, &swim_iop_lock);
	if (!swim_queue) {
		unregister_blkdev(FLOPPY_MAJOR, "fd");
		return -ENOMEM;
	}

	printk("SWIM-IOP: %s by Joshua M. Thompson (funaho@jurai.org)\n",
		DRIVER_VERSION);

	if (iop_listen(SWIM_IOP, SWIM_CHAN, swimiop_receive, "SWIM") != 0) {
		printk(KERN_ERR "SWIM-IOP: IOP channel already in use; can't initialize.\n");
		unregister_blkdev(FLOPPY_MAJOR, "fd");
		blk_cleanup_queue(swim_queue);
		return -EBUSY;
	}

	printk(KERN_ERR "SWIM_IOP: probing for installed drives.\n");

	for (i = 0 ; i < MAX_FLOPPIES ; i++) {
		memset(&floppy_states[i], 0, sizeof(struct floppy_state));
		fs = &floppy_states[floppy_count];

		swimiop_init_request(&req);
		cmd->code = CMD_STATUS;
		cmd->drive_num = i + 1;
		if (swimiop_send_request(&req) != 0) continue;
		while (!req.complete);
		if (cmd->error != 0) {
			printk(KERN_ERR "SWIM-IOP: probe on drive %d returned error %d\n", i, (uint) cmd->error);
			continue;
		}
		if (ds->installed != 0x01) continue;
		printk("SWIM-IOP: drive %d is %s (%s, %s, %s, %s)\n", i,
			drive_names[ds->info.type],
			ds->info.external? "ext" : "int",
			ds->info.scsi? "scsi" : "floppy",
			ds->info.fixed? "fixed" : "removable",
			ds->info.secondary? "secondary" : "primary");
		swimiop_status_update(floppy_count, ds);
		fs->state = idle;

		init_timer(&fs->timeout);
		floppy_count++;
	}
	printk("SWIM-IOP: detected %d installed drives.\n", floppy_count);

	for (i = 0; i < floppy_count; i++) {
		struct gendisk *disk = alloc_disk(1);
		if (!disk)
			continue;
		disk->major = FLOPPY_MAJOR;
		disk->first_minor = i;
		disk->fops = &floppy_fops;
		sprintf(disk->disk_name, "fd%d", i);
		disk->private_data = &floppy_states[i];
		disk->queue = swim_queue;
		set_capacity(disk, 2880 * 2);
		add_disk(disk);
	}

	return 0;
}

static void swimiop_init_request(struct swim_iop_req *req)
{
	req->sent = 0;
	req->complete = 0;
	req->done = NULL;
}

static int swimiop_send_request(struct swim_iop_req *req)
{
	unsigned long flags;
	int err;

	/* It's doubtful an interrupt routine would try to send */
	/* a SWIM request, but I'd rather play it safe here.    */

	local_irq_save(flags);

	if (current_req != NULL) {
		local_irq_restore(flags);
		return -ENOMEM;
	}

	current_req = req;

	/* Interrupts should be back on for iop_send_message() */

	local_irq_restore(flags);

	err = iop_send_message(SWIM_IOP, SWIM_CHAN, (void *) req,
				sizeof(req->command), (__u8 *) &req->command[0],
				swimiop_receive);

	/* No race condition here; we own current_req at this point */

	if (err) {
		current_req = NULL;
	} else {
		req->sent = 1;
	}
	return err;
}

/*
 * Receive a SWIM message from the IOP.
 *
 * This will be called in two cases:
 *
 * 1. A message has been successfully sent to the IOP.
 * 2. An unsolicited message was received from the IOP.
 */

void swimiop_receive(struct iop_msg *msg, struct pt_regs *regs)
{
	struct swim_iop_req *req;
	struct swimmsg_status *sm;
	struct swim_drvstatus *ds;

	req = current_req;

	switch(msg->status) {
		case IOP_MSGSTATUS_COMPLETE:
			memcpy(&req->command[0], &msg->reply[0], sizeof(req->command));
			req->complete = 1;
			if (req->done) (*req->done)(req);
			current_req = NULL;
			break;
		case IOP_MSGSTATUS_UNSOL:
			sm = (struct swimmsg_status *) &msg->message[0];
			ds = &sm->status;
			swimiop_status_update(sm->drive_num, ds);
			iop_complete_message(msg);
			break;
	}
}

static void swimiop_status_update(int drive_num, struct swim_drvstatus *ds)
{
	struct floppy_state *fs = &floppy_states[drive_num];

	fs->write_prot = (ds->write_prot == 0x80);
	if ((ds->disk_in_drive != 0x01) && (ds->disk_in_drive != 0x02)) {
		fs->ejected = 1;
	} else {
		fs->ejected = 0;
	}
	switch(ds->info.type) {
		case DRV_400K:
			fs->secpercyl = 10;
			fs->secpertrack = 10;
			fs->total_secs = 800;
			break;
		case DRV_800K:
			fs->secpercyl = 20;
			fs->secpertrack = 10;
			fs->total_secs = 1600;
			break;
		case DRV_FDHD:
			fs->secpercyl = 36;
			fs->secpertrack = 18;
			fs->total_secs = 2880;
			break;
		default:
			fs->secpercyl = 0;
			fs->secpertrack = 0;
			fs->total_secs = 0;
			break;
	}
}

static int swimiop_eject(struct floppy_state *fs)
{
	int err, n;
	struct swim_iop_req req;
	struct swimcmd_eject *cmd = (struct swimcmd_eject *) &req.command[0];

	err = grab_drive(fs, ejecting, 1);
	if (err) return err;

	swimiop_init_request(&req);
	cmd->code = CMD_EJECT;
	cmd->drive_num = fs->drive_num;
	err = swimiop_send_request(&req);
	if (err) {
		release_drive(fs);
		return err;
	}
	for (n = 2*HZ; n > 0; --n) {
		if (req.complete) break;
		if (signal_pending(current)) {
			err = -EINTR;
			break;
		}
		current->state = TASK_INTERRUPTIBLE;
		schedule_timeout(1);
	}
	release_drive(fs);
	return cmd->error;
}

static struct floppy_struct floppy_type =
	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */

static int floppy_ioctl(struct inode *inode, struct file *filp,
			unsigned int cmd, unsigned long param)
{
	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
	int err;

	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch (cmd) {
	case FDEJECT:
		if (fs->ref_count != 1)
			return -EBUSY;
		err = swimiop_eject(fs);
		return err;
	case FDGETPRM:
	        if (copy_to_user((void *) param, (void *) &floppy_type,
				 sizeof(struct floppy_struct)))
			return -EFAULT;
		return 0;
	}
	return -ENOTTY;
}

static int floppy_open(struct inode *inode, struct file *filp)
{
	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;

	if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
		return -EBUSY;

	if ((filp->f_flags & O_NDELAY) == 0 && (filp->f_mode & 3)) {
		check_disk_change(inode->i_bdev);
		if (fs->ejected)
			return -ENXIO;
	}

	if ((filp->f_mode & 2) && fs->write_prot)
		return -EROFS;

	if (filp->f_flags & O_EXCL)
		fs->ref_count = -1;
	else
		++fs->ref_count;

	return 0;
}

static int floppy_release(struct inode *inode, struct file *filp)
{
	struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
	if (fs->ref_count > 0)
		fs->ref_count--;
	return 0;
}

static int floppy_check_change(struct gendisk *disk)
{
	struct floppy_state *fs = disk->private_data;
	return fs->ejected;
}

static int floppy_revalidate(struct gendisk *disk)
{
	struct floppy_state *fs = disk->private_data;
	grab_drive(fs, revalidating, 0);
	/* yadda, yadda */
	release_drive(fs);
	return 0;
}

static void floppy_off(unsigned int nr)
{
}

static int grab_drive(struct floppy_state *fs, enum swim_state state,
		      int interruptible)
{
	unsigned long flags;

	local_irq_save(flags);
	if (fs->state != idle) {
		++fs->wanted;
		while (fs->state != available) {
			if (interruptible && signal_pending(current)) {
				--fs->wanted;
				local_irq_restore(flags);
				return -EINTR;
			}
			interruptible_sleep_on(&fs->wait);
		}
		--fs->wanted;
	}
	fs->state = state;
	local_irq_restore(flags);
	return 0;
}

static void release_drive(struct floppy_state *fs)
{
	unsigned long flags;

	local_irq_save(flags);
	fs->state = idle;
	start_request(fs);
	local_irq_restore(flags);
}

static void set_timeout(struct floppy_state *fs, int nticks,
			void (*proc)(unsigned long))
{
	unsigned long flags;

	local_irq_save(flags);
	if (fs->timeout_pending)
		del_timer(&fs->timeout);
	init_timer(&fs->timeout);
	fs->timeout.expires = jiffies + nticks;
	fs->timeout.function = proc;
	fs->timeout.data = (unsigned long) fs;
	add_timer(&fs->timeout);
	fs->timeout_pending = 1;
	local_irq_restore(flags);
}

static void do_fd_request(request_queue_t * q)
{
	int i;

	for (i = 0 ; i < floppy_count ; i++) {
		start_request(&floppy_states[i]);
	}
}

static void fd_request_complete(struct swim_iop_req *req)
{
	struct floppy_state *fs = req->fs;
	struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req->command[0];

	del_timer(&fs->timeout);
	fs->timeout_pending = 0;
	fs->state = idle;
	if (cmd->error) {
		printk(KERN_ERR "SWIM-IOP: error %d on read/write request.\n", cmd->error);
		end_request(CURRENT, 0);
	} else {
		CURRENT->sector += cmd->num_blocks;
		CURRENT->current_nr_sectors -= cmd->num_blocks;
		if (CURRENT->current_nr_sectors <= 0) {
			end_request(CURRENT, 1);
			return;
		}
	}
	start_request(fs);
}

static void fd_request_timeout(unsigned long data)
{
	struct floppy_state *fs = (struct floppy_state *) data;

	fs->timeout_pending = 0;
	end_request(CURRENT, 0);
	fs->state = idle;
}

static void start_request(struct floppy_state *fs)
{
	volatile struct swim_iop_req req;
	struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req.command[0];

	if (fs->state == idle && fs->wanted) {
		fs->state = available;
		wake_up(&fs->wait);
		return;
	}
	while (CURRENT && fs->state == idle) {
		if (CURRENT->bh && !buffer_locked(CURRENT->bh))
			panic("floppy: block not locked");
#if 0
		printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
		       CURRENT->rq_disk->disk_name, CURRENT->cmd,
		       CURRENT->sector, CURRENT->nr_sectors, CURRENT->buffer);
		printk("           rq_status=%d errors=%d current_nr_sectors=%ld\n",
		       CURRENT->rq_status, CURRENT->errors, CURRENT->current_nr_sectors);
#endif

		if (CURRENT->sector < 0 || CURRENT->sector >= fs->total_secs) {
			end_request(CURRENT, 0);
			continue;
		}
		if (CURRENT->current_nr_sectors == 0) {
			end_request(CURRENT, 1);
			continue;
		}
		if (fs->ejected) {
			end_request(CURRENT, 0);
			continue;
		}

		swimiop_init_request(&req);
		req.fs = fs;
		req.done = fd_request_complete;

		if (CURRENT->cmd == WRITE) {
			if (fs->write_prot) {
				end_request(CURRENT, 0);
				continue;
			}
			cmd->code = CMD_WRITE;
		} else {
			cmd->code = CMD_READ;

		}
		cmd->drive_num = fs->drive_num;
		cmd->buffer = CURRENT->buffer;
		cmd->first_block = CURRENT->sector;
		cmd->num_blocks = CURRENT->current_nr_sectors;

		if (swimiop_send_request(&req)) {
			end_request(CURRENT, 0);
			continue;
		}

		set_timeout(fs, HZ*CURRENT->current_nr_sectors,
				fd_request_timeout);

		fs->state = transferring;
	}
}
OpenPOWER on IntegriCloud