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