fd.c revision 1.50.8.1
1 /* $NetBSD: fd.c,v 1.50.8.1 2002/05/16 16:15:24 gehenna Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Christian E. Hopps 5 * Copyright (c) 1996 Ezra Story 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by Christian E. Hopps. 19 * This product includes software developed by Ezra Story. 20 * 4. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 26 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 __KERNEL_RCSID(0, "$NetBSD: fd.c,v 1.50.8.1 2002/05/16 16:15:24 gehenna Exp $"); 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/callout.h> 41 #include <sys/kernel.h> 42 #include <sys/malloc.h> 43 #include <sys/buf.h> 44 #include <sys/device.h> 45 #include <sys/ioctl.h> 46 #include <sys/fcntl.h> 47 #include <sys/disklabel.h> 48 #include <sys/disk.h> 49 #include <sys/dkbad.h> 50 #include <sys/proc.h> 51 #include <sys/conf.h> 52 #include <machine/cpu.h> 53 #include <amiga/amiga/device.h> 54 #include <amiga/amiga/custom.h> 55 #include <amiga/amiga/cia.h> 56 #include <amiga/amiga/cc.h> 57 58 #include "locators.h" 59 60 enum fdc_bits { FDB_CHANGED = 2, FDB_PROTECT, FDB_CYLZERO, FDB_READY }; 61 /* 62 * partitions in fd represent different format floppies 63 * partition a is 0 etc.. 64 */ 65 enum fd_parttypes { 66 FDAMIGAPART = 0, 67 FDMSDOSPART, 68 FDMAXPARTS 69 }; 70 71 #define FDBBSIZE (8192) 72 #define FDSBSIZE (8192) 73 74 #define FDUNIT(dev) DISKUNIT(dev) 75 #define FDPART(dev) DISKPART(dev) 76 #define FDMAKEDEV(m, u, p) MAKEDISKDEV((m), (u), (p)) 77 78 /* that's nice, but we don't want to always use this as an amiga drive 79 bunghole :-) */ 80 #define FDNHEADS (2) /* amiga drives always have 2 heads */ 81 #define FDSECSIZE (512) /* amiga drives always have 512 byte sectors */ 82 #define FDSECLWORDS (128) 83 84 #define FDSETTLEDELAY (18000) /* usec delay after seeking after switch dir */ 85 #define FDSTEPDELAY (3500) /* usec delay after steping */ 86 #define FDPRESIDEDELAY (1000) /* usec delay before writing can occur */ 87 #define FDWRITEDELAY (1300) /* usec delay after write */ 88 89 #define FDSTEPOUT (1) /* decrease track step */ 90 #define FDSTEPIN (0) /* increase track step */ 91 92 #define FDCUNITMASK (0x78) /* mask for all units (bits 6-3) */ 93 94 #define FDRETRIES (2) /* default number of retries */ 95 #define FDMAXUNITS (4) /* maximum number of supported units */ 96 97 #define DISKLEN_READ (0) /* fake mask for reading */ 98 #define DISKLEN_WRITE (1 << 14) /* bit for writing */ 99 #define DISKLEN_DMAEN (1 << 15) /* dma go */ 100 #define DMABUFSZ ((DISKLEN_WRITE - 1) * 2) /* largest dma possible */ 101 102 #define FDMFMSYNC (0x4489) 103 #define FDMFMID (0x5554) 104 #define FDMFMDATA (0x5545) 105 #define FDMFMGAP1 (0x9254) 106 #define FDMFMGAP2 (0xAAAA) 107 #define FDMFMGAP3 (0x9254) 108 #define CRC16POLY (0x1021) /* (x^16) + x^12 + x^5 + x^0 */ 109 110 /* 111 * Msdos-type MFM encode/decode 112 */ 113 static u_char msdecode[128]; 114 static u_char msencode[16] = 115 { 116 0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15, 117 0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55 118 }; 119 static u_short mscrctab[256]; 120 121 /* 122 5554 aaaa aaaa aaa5 2aa4 4452 aa51 123 00 00 03 02 ac 0d 124 */ 125 126 /* 127 * floppy device type 128 */ 129 struct fdtype { 130 u_int driveid; /* drive identification (from drive) */ 131 u_int ncylinders; /* number of cylinders on drive */ 132 u_int amiga_nsectors; /* number of sectors per amiga track */ 133 u_int msdos_nsectors; /* number of sectors per msdos track */ 134 u_int nreadw; /* number of words (short) read per track */ 135 u_int nwritew; /* number of words (short) written per track */ 136 u_int gap; /* track gap size in long words */ 137 u_int precomp[2]; /* 1st and 2nd precomp values */ 138 char *desc; /* description of drive type (useq) */ 139 }; 140 141 /* 142 * floppy disk device data 143 */ 144 struct fd_softc { 145 struct device sc_dv; /* generic device info; must come first */ 146 struct disk dkdev; /* generic disk info */ 147 struct buf_queue bufq; /* queue pending I/O operations */ 148 struct buf curbuf; /* state of current I/O operation */ 149 struct callout calibrate_ch; 150 struct callout motor_ch; 151 struct fdtype *type; 152 void *cachep; /* cached track data (write through) */ 153 int cachetrk; /* cahced track -1 for none */ 154 int hwunit; /* unit for amiga controlling hw */ 155 int unitmask; /* mask for cia select deslect */ 156 int pstepdir; /* previous step direction */ 157 int curcyl; /* current curcyl head positioned on */ 158 int flags; /* misc flags */ 159 int wlabel; 160 int stepdelay; /* useq to delay after seek user setable */ 161 int nsectors; /* number of sectors per track */ 162 int openpart; /* which partition [ab] == [12] is open */ 163 short retries; /* number of times to retry failed io */ 164 short retried; /* number of times current io retried */ 165 int bytespersec; /* number of bytes per sector */ 166 }; 167 168 /* fd_softc->flags */ 169 #define FDF_MOTORON (0x01) /* motor is running */ 170 #define FDF_MOTOROFF (0x02) /* motor is waiting to be turned off */ 171 #define FDF_WMOTOROFF (0x04) /* unit wants a wakeup after off */ 172 #define FDF_DIRTY (0x08) /* track cache needs write */ 173 #define FDF_WRITEWAIT (0x10) /* need to head select delay on next setpos */ 174 #define FDF_HAVELABEL (0x20) /* label is valid */ 175 #define FDF_JUSTFLUSH (0x40) /* don't bother caching track. */ 176 #define FDF_NOTRACK0 (0x80) /* was not able to recalibrate drive */ 177 178 int fdc_wantwakeup; 179 int fdc_side; 180 void *fdc_dmap; 181 struct fd_softc *fdc_indma; 182 int fdc_dmalen; 183 int fdc_dmawrite; 184 185 struct fdcargs { 186 struct fdtype *type; 187 int unit; 188 }; 189 190 int fdcmatch(struct device *, struct cfdata *, void *); 191 void fdcattach(struct device *, struct device *, void *); 192 int fdcprint(void *, const char *); 193 int fdmatch(struct device *, struct cfdata *, void *); 194 void fdattach(struct device *, struct device *, void *); 195 196 void fdintr(int); 197 void fdidxintr(void); 198 int fdloaddisk(struct fd_softc *); 199 void fdgetdefaultlabel(struct fd_softc *, struct disklabel *, int); 200 int fdgetdisklabel(struct fd_softc *, dev_t); 201 int fdsetdisklabel(struct fd_softc *, struct disklabel *); 202 int fdputdisklabel(struct fd_softc *, dev_t); 203 struct fdtype * fdcgetfdtype(int); 204 void fdmotoroff(void *); 205 void fdsetpos(struct fd_softc *, int, int); 206 void fdselunit(struct fd_softc *); 207 void fdstart(struct fd_softc *); 208 void fdcont(struct fd_softc *); 209 void fddmastart(struct fd_softc *, int); 210 void fdcalibrate(void *); 211 void fddmadone(struct fd_softc *, int); 212 void fddone(struct fd_softc *); 213 void fdfindwork(int); 214 void fdminphys(struct buf *); 215 void fdcachetoraw(struct fd_softc *); 216 void amcachetoraw(struct fd_softc *); 217 int amrawtocache(struct fd_softc *); 218 u_long *fdfindsync(u_long *, u_long *); 219 int fdrawtocache(struct fd_softc *); 220 void mscachetoraw(struct fd_softc *); 221 int msrawtocache(struct fd_softc *); 222 u_long *mfmblkencode(u_long *, u_long *, u_long *, int); 223 u_long *mfmblkdecode(u_long *, u_long *, u_long *, int); 224 u_short *msblkdecode(u_short *, u_char *, int); 225 u_short *msblkencode(u_short *, u_char *, int, u_short *); 226 227 /* 228 * read size is (nsectors + 1) * mfm secsize + gap bytes + 2 shorts 229 * write size is nsectors * mfm secsize + gap bytes + 3 shorts 230 * the extra shorts are to deal with a dma hw bug in the controller 231 * they are probably too much (I belive the bug is 1 short on write and 232 * 3 bits on read) but there is no need to be cheap here. 233 */ 234 #define MAXTRKSZ (22 * FDSECSIZE) 235 struct fdtype fdtype[] = { 236 { 0x00000000, 80, 11, 9, 7358, 6815, 414, { 80, 161 }, "3.5dd" }, 237 { 0x55555555, 40, 11, 9, 7358, 6815, 414, { 80, 161 }, "5.25dd" }, 238 { 0xAAAAAAAA, 80, 22, 18, 14716, 13630, 828, { 80, 161 }, "3.5hd" } 239 }; 240 int nfdtype = sizeof(fdtype) / sizeof(*fdtype); 241 242 struct cfattach fd_ca = { 243 sizeof(struct fd_softc), fdmatch, fdattach 244 }; 245 246 extern struct cfdriver fd_cd; 247 248 dev_type_open(fdopen); 249 dev_type_close(fdclose); 250 dev_type_read(fdread); 251 dev_type_write(fdwrite); 252 dev_type_ioctl(fdioctl); 253 dev_type_strategy(fdstrategy); 254 255 const struct bdevsw fd_bdevsw = { 256 fdopen, fdclose, fdstrategy, fdioctl, nodump, nosize, D_DISK 257 }; 258 259 const struct cdevsw fd_cdevsw = { 260 fdopen, fdclose, fdread, fdwrite, fdioctl, 261 nostop, notty, nopoll, nommap, D_DISK 262 }; 263 264 struct dkdriver fddkdriver = { fdstrategy }; 265 266 struct cfattach fdc_ca = { 267 sizeof(struct device), fdcmatch, fdcattach 268 }; 269 270 /* 271 * all hw access through macros, this helps to hide the active low 272 * properties 273 */ 274 275 #define FDUNITMASK(unit) (1 << (3 + (unit))) 276 277 /* 278 * select units using mask 279 */ 280 #define FDSELECT(um) do { ciab.prb &= ~(um); } while (0) 281 282 /* 283 * deselect units using mask 284 */ 285 #define FDDESELECT(um) do { ciab.prb |= (um); delay(1); } while (0) 286 287 /* 288 * test hw condition bits 289 */ 290 #define FDTESTC(bit) ((ciaa.pra & (1 << (bit))) == 0) 291 292 /* 293 * set motor for select units, true motor on else off 294 */ 295 #define FDSETMOTOR(on) do { \ 296 if (on) ciab.prb &= ~CIAB_PRB_MTR; else ciab.prb |= CIAB_PRB_MTR; \ 297 } while (0) 298 299 /* 300 * set head for select units 301 */ 302 #define FDSETHEAD(head) do { \ 303 if (head) ciab.prb &= ~CIAB_PRB_SIDE; else ciab.prb |= CIAB_PRB_SIDE; \ 304 delay(1); } while (0) 305 306 /* 307 * select direction, true towards spindle else outwards 308 */ 309 #define FDSETDIR(in) do { \ 310 if (in) ciab.prb &= ~CIAB_PRB_DIR; else ciab.prb |= CIAB_PRB_DIR; \ 311 delay(1); } while (0) 312 313 /* 314 * step the selected units 315 */ 316 #define FDSTEP do { \ 317 ciab.prb &= ~CIAB_PRB_STEP; ciab.prb |= CIAB_PRB_STEP; \ 318 } while (0) 319 320 #define FDDMASTART(len, towrite) do { \ 321 int dmasz = (len) | ((towrite) ? DISKLEN_WRITE : 0) | DISKLEN_DMAEN; \ 322 custom.dsklen = dmasz; custom.dsklen = dmasz; } while (0) 323 324 #define FDDMASTOP do { custom.dsklen = 0; } while (0) 325 326 327 int 328 fdcmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 329 { 330 static int fdc_matched = 0; 331 332 /* Allow only once instance. */ 333 if (matchname("fdc", auxp) == 0 || fdc_matched) 334 return(0); 335 if ((fdc_dmap = alloc_chipmem(DMABUFSZ)) == NULL) { 336 printf("fdc: unable to allocate dma buffer\n"); 337 return(0); 338 } 339 340 fdc_matched = 1; 341 return(1); 342 } 343 344 void 345 fdcattach(struct device *pdp, struct device *dp, void *auxp) 346 { 347 struct fdcargs args; 348 349 printf(": dmabuf pa 0x%x", kvtop(fdc_dmap)); 350 printf(": dmabuf ka %p\n", fdc_dmap); 351 args.unit = 0; 352 args.type = fdcgetfdtype(args.unit); 353 354 fdc_side = -1; 355 config_found(dp, &args, fdcprint); 356 for (args.unit++; args.unit < FDMAXUNITS; args.unit++) { 357 if ((args.type = fdcgetfdtype(args.unit)) == NULL) 358 continue; 359 config_found(dp, &args, fdcprint); 360 } 361 } 362 363 int 364 fdcprint(void *auxp, const char *pnp) 365 { 366 struct fdcargs *fcp; 367 368 fcp = auxp; 369 if (pnp) 370 printf("fd%d at %s unit %d:", fcp->unit, pnp, 371 fcp->type->driveid); 372 return(UNCONF); 373 } 374 375 /*ARGSUSED*/ 376 int 377 fdmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 378 { 379 struct fdcargs *fdap; 380 381 fdap = auxp; 382 if (cfp->cf_loc[FDCCF_UNIT] == fdap->unit || 383 cfp->cf_loc[FDCCF_UNIT] == FDCCF_UNIT_DEFAULT) 384 return(1); 385 386 return(0); 387 } 388 389 void 390 fdattach(struct device *pdp, struct device *dp, void *auxp) 391 { 392 struct fdcargs *ap; 393 struct fd_softc *sc; 394 int i; 395 396 ap = auxp; 397 sc = (struct fd_softc *)dp; 398 399 BUFQ_INIT(&sc->bufq); 400 callout_init(&sc->calibrate_ch); 401 callout_init(&sc->motor_ch); 402 403 sc->curcyl = sc->cachetrk = -1; 404 sc->openpart = -1; 405 sc->type = ap->type; 406 sc->hwunit = ap->unit; 407 sc->unitmask = 1 << (3 + ap->unit); 408 sc->retries = FDRETRIES; 409 sc->stepdelay = FDSTEPDELAY; 410 sc->bytespersec = 512; 411 printf(" unit %d: %s %d cyl, %d head, %d sec [%d sec], 512 bytes/sec\n", 412 sc->hwunit, sc->type->desc, sc->type->ncylinders, FDNHEADS, 413 sc->type->amiga_nsectors, sc->type->msdos_nsectors); 414 415 /* 416 * Initialize and attach the disk structure. 417 */ 418 sc->dkdev.dk_name = sc->sc_dv.dv_xname; 419 sc->dkdev.dk_driver = &fddkdriver; 420 disk_attach(&sc->dkdev); 421 422 /* 423 * calibrate the drive 424 */ 425 fdsetpos(sc, 0, 0); 426 fdsetpos(sc, sc->type->ncylinders, 0); 427 fdsetpos(sc, 0, 0); 428 fdmotoroff(sc); 429 430 /* 431 * precalc msdos MFM and CRC 432 */ 433 for (i = 0; i < 128; i++) 434 msdecode[i] = 0xff; 435 for (i = 0; i < 16; i++) 436 msdecode[msencode[i]] = i; 437 for (i = 0; i < 256; i++) { 438 mscrctab[i] = (0x1021 * (i & 0xf0)) ^ (0x1021 * (i & 0x0f)) ^ 439 (0x1021 * (i >> 4)); 440 } 441 442 /* 443 * enable disk related interrupts 444 */ 445 custom.dmacon = DMAF_SETCLR | DMAF_MASTER | DMAF_DISK; 446 custom.intena = INTF_SETCLR | INTF_DSKBLK; 447 ciab.icr = CIA_ICR_FLG; 448 } 449 450 /*ARGSUSED*/ 451 int 452 fdopen(dev_t dev, int flags, int devtype, struct proc *p) 453 { 454 struct fd_softc *sc; 455 int wasopen, fwork, error, s; 456 457 error = 0; 458 459 if (FDPART(dev) >= FDMAXPARTS) 460 return(ENXIO); 461 462 if ((sc = getsoftc(fd_cd, FDUNIT(dev))) == NULL) 463 return(ENXIO); 464 if (sc->flags & FDF_NOTRACK0) 465 return(ENXIO); 466 if (sc->cachep == NULL) 467 sc->cachep = malloc(MAXTRKSZ, M_DEVBUF, M_WAITOK); 468 469 s = splbio(); 470 /* 471 * if we are sleeping in fdclose(); waiting for a chance to 472 * shut the motor off, do a sleep here also. 473 */ 474 while (sc->flags & FDF_WMOTOROFF) 475 tsleep(fdmotoroff, PRIBIO, "fdopen", 0); 476 477 fwork = 0; 478 /* 479 * if not open let user open request type, otherwise 480 * ensure they are trying to open same type. 481 */ 482 if (sc->openpart == FDPART(dev)) 483 wasopen = 1; 484 else if (sc->openpart == -1) { 485 sc->openpart = FDPART(dev); 486 wasopen = 0; 487 } else { 488 wasopen = 1; 489 error = EPERM; 490 goto done; 491 } 492 493 /* 494 * wait for current io to complete if any 495 */ 496 if (fdc_indma) { 497 fwork = 1; 498 fdc_wantwakeup++; 499 tsleep(fdopen, PRIBIO, "fdopen", 0); 500 } 501 if ((error = fdloaddisk(sc)) != 0) 502 goto done; 503 if ((error = fdgetdisklabel(sc, dev)) != 0) 504 goto done; 505 #ifdef FDDEBUG 506 printf(" open successful\n"); 507 #endif 508 done: 509 /* 510 * if we requested that fddone()->fdfindwork() wake us, allow it to 511 * complete its job now 512 */ 513 if (fwork) 514 fdfindwork(FDUNIT(dev)); 515 splx(s); 516 517 /* 518 * if we were not open and we marked us so reverse that. 519 */ 520 if (error && wasopen == 0) 521 sc->openpart = -1; 522 return(error); 523 } 524 525 /*ARGSUSED*/ 526 int 527 fdclose(dev_t dev, int flags, int devtype, struct proc *p) 528 { 529 struct fd_softc *sc; 530 int s; 531 532 #ifdef FDDEBUG 533 printf("fdclose()\n"); 534 #endif 535 sc = getsoftc(fd_cd, FDUNIT(dev)); 536 s = splbio(); 537 if (sc->flags & FDF_MOTORON) { 538 sc->flags |= FDF_WMOTOROFF; 539 tsleep(fdmotoroff, PRIBIO, "fdclose", 0); 540 sc->flags &= ~FDF_WMOTOROFF; 541 wakeup(fdmotoroff); 542 } 543 sc->openpart = -1; 544 splx(s); 545 return(0); 546 } 547 548 int 549 fdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) 550 { 551 struct fd_softc *sc; 552 int error, wlab; 553 554 sc = getsoftc(fd_cd, FDUNIT(dev)); 555 556 if ((sc->flags & FDF_HAVELABEL) == 0) 557 return(EBADF); 558 559 switch (cmd) { 560 case DIOCSBAD: 561 return(EINVAL); 562 case DIOCSRETRIES: 563 if (*(int *)addr < 0) 564 return(EINVAL); 565 sc->retries = *(int *)addr; 566 return(0); 567 case DIOCSSTEP: 568 if (*(int *)addr < FDSTEPDELAY) 569 return(EINVAL); 570 sc->dkdev.dk_label->d_trkseek = sc->stepdelay = *(int *)addr; 571 return(0); 572 case DIOCGDINFO: 573 *(struct disklabel *)addr = *(sc->dkdev.dk_label); 574 return(0); 575 case DIOCGPART: 576 ((struct partinfo *)addr)->disklab = sc->dkdev.dk_label; 577 ((struct partinfo *)addr)->part = 578 &sc->dkdev.dk_label->d_partitions[FDPART(dev)]; 579 return(0); 580 case DIOCSDINFO: 581 if ((flag & FWRITE) == 0) 582 return(EBADF); 583 return(fdsetdisklabel(sc, (struct disklabel *)addr)); 584 case DIOCWDINFO: 585 if ((flag & FWRITE) == 0) 586 return(EBADF); 587 if ((error = fdsetdisklabel(sc, (struct disklabel *)addr)) != 0) 588 return(error); 589 wlab = sc->wlabel; 590 sc->wlabel = 1; 591 error = fdputdisklabel(sc, dev); 592 sc->wlabel = wlab; 593 return(error); 594 case DIOCWLABEL: 595 if ((flag & FWRITE) == 0) 596 return(EBADF); 597 sc->wlabel = *(int *)addr; 598 return(0); 599 case DIOCGDEFLABEL: 600 fdgetdefaultlabel(sc, (struct disklabel *)addr, FDPART(dev)); 601 return(0); 602 default: 603 return(ENOTTY); 604 } 605 } 606 607 int 608 fdread(dev_t dev, struct uio *uio, int flags) 609 { 610 return (physio(fdstrategy, NULL, dev, B_READ, fdminphys, uio)); 611 } 612 613 int 614 fdwrite(dev_t dev, struct uio *uio, int flags) 615 { 616 return (physio(fdstrategy, NULL, dev, B_WRITE, fdminphys, uio)); 617 } 618 619 620 void 621 fdintr(int flag) 622 { 623 int s; 624 625 s = splbio(); 626 if (fdc_indma) 627 fddmadone(fdc_indma, 0); 628 splx(s); 629 } 630 631 void 632 fdidxintr(void) 633 { 634 if (fdc_indma && fdc_dmalen) { 635 /* 636 * turn off intr and start actual dma 637 */ 638 ciab.icr = CIA_ICR_FLG; 639 FDDMASTART(fdc_dmalen, fdc_dmawrite); 640 fdc_dmalen = 0; 641 } 642 } 643 644 void 645 fdstrategy(struct buf *bp) 646 { 647 struct disklabel *lp; 648 struct fd_softc *sc; 649 int unit, part, s; 650 651 unit = FDUNIT(bp->b_dev); 652 part = FDPART(bp->b_dev); 653 sc = getsoftc(fd_cd, unit); 654 655 #ifdef FDDEBUG 656 printf("fdstrategy: 0x%x\n", bp); 657 #endif 658 /* 659 * check for valid partition and bounds 660 */ 661 lp = sc->dkdev.dk_label; 662 if ((sc->flags & FDF_HAVELABEL) == 0) { 663 bp->b_error = EIO; 664 goto bad; 665 } 666 if (bounds_check_with_label(bp, lp, sc->wlabel) <= 0) 667 goto done; 668 669 /* 670 * trans count of zero or bounds check indicates io is done 671 * we are done. 672 */ 673 if (bp->b_bcount == 0) 674 goto done; 675 676 bp->b_rawblkno = bp->b_blkno; 677 678 /* 679 * queue the buf and kick the low level code 680 */ 681 s = splbio(); 682 disksort_cylinder(&sc->bufq, bp); 683 fdstart(sc); 684 splx(s); 685 return; 686 bad: 687 bp->b_flags |= B_ERROR; 688 done: 689 bp->b_resid = bp->b_bcount; 690 biodone(bp); 691 } 692 693 /* 694 * make sure disk is loaded and label is up-to-date. 695 */ 696 int 697 fdloaddisk(struct fd_softc *sc) 698 { 699 /* 700 * if diskchange is low step drive to 0 then up one then to zero. 701 */ 702 fdselunit(sc); /* make sure the unit is selected */ 703 if (FDTESTC(FDB_CHANGED)) { 704 fdsetpos(sc, 0, 0); 705 sc->cachetrk = -1; /* invalidate the cache */ 706 sc->flags &= ~FDF_HAVELABEL; 707 fdsetpos(sc, FDNHEADS, 0); 708 fdsetpos(sc, 0, 0); 709 if (FDTESTC(FDB_CHANGED)) { 710 fdmotoroff(sc); 711 FDDESELECT(sc->unitmask); 712 return(ENXIO); 713 } 714 } 715 FDDESELECT(sc->unitmask); 716 fdmotoroff(sc); 717 sc->type = fdcgetfdtype(sc->hwunit); 718 if (sc->type == NULL) 719 return(ENXIO); 720 if (sc->openpart == FDMSDOSPART) 721 sc->nsectors = sc->type->msdos_nsectors; 722 else 723 sc->nsectors = sc->type->amiga_nsectors; 724 return(0); 725 } 726 727 void 728 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 729 /* (variable part) XXX ick */ 730 { 731 732 bzero(lp, sizeof(struct disklabel)); 733 lp->d_secsize = FDSECSIZE; 734 lp->d_ntracks = FDNHEADS; 735 lp->d_ncylinders = sc->type->ncylinders; 736 lp->d_nsectors = sc->nsectors; 737 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 738 lp->d_type = DTYPE_FLOPPY; 739 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 740 lp->d_rpm = 300; /* good guess I suppose. */ 741 lp->d_interleave = 1; /* should change when adding msdos */ 742 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 743 lp->d_bbsize = 0; 744 lp->d_sbsize = 0; 745 lp->d_partitions[part].p_size = lp->d_secperunit; 746 lp->d_partitions[part].p_fstype = FS_UNUSED; 747 lp->d_partitions[part].p_fsize = 1024; 748 lp->d_partitions[part].p_frag = 8; 749 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 750 lp->d_npartitions = part + 1; 751 lp->d_magic = lp->d_magic2 = DISKMAGIC; 752 lp->d_checksum = dkcksum(lp); 753 } 754 755 /* 756 * read disk label, if present otherwise create one 757 * return a new label if raw part and none found, otherwise err. 758 */ 759 int 760 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 761 { 762 struct disklabel *lp, *dlp; 763 struct cpu_disklabel *clp; 764 struct buf *bp; 765 int error, part; 766 767 if (sc->flags & FDF_HAVELABEL && 768 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 769 return(0); 770 #ifdef FDDEBUG 771 printf("fdgetdisklabel()\n"); 772 #endif 773 part = FDPART(dev); 774 lp = sc->dkdev.dk_label; 775 clp = sc->dkdev.dk_cpulabel; 776 bzero(lp, sizeof(struct disklabel)); 777 bzero(clp, sizeof(struct cpu_disklabel)); 778 779 lp->d_secsize = FDSECSIZE; 780 lp->d_ntracks = FDNHEADS; 781 lp->d_ncylinders = sc->type->ncylinders; 782 lp->d_nsectors = sc->nsectors; 783 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 784 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 785 lp->d_npartitions = part + 1; 786 lp->d_partitions[part].p_size = lp->d_secperunit; 787 lp->d_partitions[part].p_fstype = FS_UNUSED; 788 lp->d_partitions[part].p_fsize = 1024; 789 lp->d_partitions[part].p_frag = 8; 790 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 791 792 sc->flags |= FDF_HAVELABEL; 793 794 bp = (void *)geteblk((int)lp->d_secsize); 795 bp->b_dev = dev; 796 bp->b_blkno = 0; 797 bp->b_cylinder = 0; 798 bp->b_bcount = FDSECSIZE; 799 bp->b_flags |= B_READ; 800 fdstrategy(bp); 801 if ((error = biowait(bp)) != 0) 802 goto nolabel; 803 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 804 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 805 dkcksum(dlp)) { 806 error = EINVAL; 807 goto nolabel; 808 } 809 bcopy(dlp, lp, sizeof(struct disklabel)); 810 if (lp->d_trkseek > FDSTEPDELAY) 811 sc->stepdelay = lp->d_trkseek; 812 brelse(bp); 813 return(0); 814 nolabel: 815 fdgetdefaultlabel(sc, lp, part); 816 brelse(bp); 817 return(0); 818 } 819 820 /* 821 * set the incore copy of this units disklabel 822 */ 823 int 824 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 825 { 826 struct disklabel *clp; 827 struct partition *pp; 828 829 /* 830 * must have at least opened raw unit to fetch the 831 * raw_part stuff. 832 */ 833 if ((sc->flags & FDF_HAVELABEL) == 0) 834 return(EINVAL); 835 clp = sc->dkdev.dk_label; 836 /* 837 * make sure things check out and we only have one valid 838 * partition 839 */ 840 #ifdef FDDEBUG 841 printf("fdsetdisklabel\n"); 842 #endif 843 if (lp->d_secsize != FDSECSIZE || 844 lp->d_nsectors != clp->d_nsectors || 845 lp->d_ntracks != FDNHEADS || 846 lp->d_ncylinders != clp->d_ncylinders || 847 lp->d_secpercyl != clp->d_secpercyl || 848 lp->d_secperunit != clp->d_secperunit || 849 lp->d_magic != DISKMAGIC || 850 lp->d_magic2 != DISKMAGIC || 851 lp->d_npartitions == 0 || 852 lp->d_npartitions > FDMAXPARTS || 853 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 854 dkcksum(lp)) 855 return(EINVAL); 856 /* 857 * if any partitions are present make sure they 858 * represent the currently open type 859 */ 860 if ((pp = &lp->d_partitions[0])->p_size) { 861 if ((pp = &lp->d_partitions[1])->p_size == 0) 862 goto done; 863 else if (sc->openpart != 1) 864 return(EINVAL); 865 } else if (sc->openpart != 0) 866 return(EINVAL); 867 /* 868 * make sure selected partition is within bounds 869 * XXX on the second check, its to handle a bug in 870 * XXX the cluster routines as they require mutliples 871 * XXX of NBPG currently 872 */ 873 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 874 (pp->p_frag * pp->p_fsize % NBPG)) 875 return(EINVAL); 876 done: 877 bcopy(lp, clp, sizeof(struct disklabel)); 878 return(0); 879 } 880 881 /* 882 * write out the incore copy of this units disklabel 883 */ 884 int 885 fdputdisklabel(struct fd_softc *sc, dev_t dev) 886 { 887 struct disklabel *lp, *dlp; 888 struct buf *bp; 889 int error; 890 891 if ((sc->flags & FDF_HAVELABEL) == 0) 892 return(EBADF); 893 #ifdef FDDEBUG 894 printf("fdputdisklabel\n"); 895 #endif 896 /* 897 * get buf and read in sector 0 898 */ 899 lp = sc->dkdev.dk_label; 900 bp = geteblk((int)lp->d_secsize); 901 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 902 bp->b_blkno = 0; 903 bp->b_cylinder = 0; 904 bp->b_bcount = FDSECSIZE; 905 bp->b_flags |= B_READ; 906 fdstrategy(bp); 907 if ((error = biowait(bp)) != 0) 908 goto done; 909 /* 910 * copy disklabel to buf and write it out syncronous 911 */ 912 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 913 bcopy(lp, dlp, sizeof(struct disklabel)); 914 bp->b_blkno = 0; 915 bp->b_cylinder = 0; 916 bp->b_flags &= ~(B_READ|B_DONE); 917 bp->b_flags |= B_WRITE; 918 fdstrategy(bp); 919 error = biowait(bp); 920 done: 921 brelse(bp); 922 return(error); 923 } 924 925 /* 926 * figure out drive type or NULL if none. 927 */ 928 struct fdtype * 929 fdcgetfdtype(int unit) 930 { 931 struct fdtype *ftp; 932 u_long id, idb; 933 int cnt, umask; 934 935 id = 0; 936 umask = 1 << (3 + unit); 937 938 FDDESELECT(FDCUNITMASK); 939 940 FDSETMOTOR(1); 941 delay(1); 942 FDSELECT(umask); 943 delay(1); 944 FDDESELECT(umask); 945 946 FDSETMOTOR(0); 947 delay(1); 948 FDSELECT(umask); 949 delay(1); 950 FDDESELECT(umask); 951 952 for (idb = 0x80000000; idb; idb >>= 1) { 953 FDSELECT(umask); 954 delay(1); 955 if (FDTESTC(FDB_READY) == 0) 956 id |= idb; 957 FDDESELECT(umask); 958 delay(1); 959 } 960 #ifdef FDDEBUG 961 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 962 #endif 963 964 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 965 if (ftp->driveid == id) 966 return(ftp); 967 /* 968 * 3.5dd's at unit 0 do not always return id. 969 */ 970 if (unit == 0) 971 return(fdtype); 972 return(NULL); 973 } 974 975 /* 976 * turn motor off if possible otherwise mark as needed and will be done 977 * later. 978 */ 979 void 980 fdmotoroff(void *arg) 981 { 982 struct fd_softc *sc; 983 int s; 984 985 sc = arg; 986 s = splbio(); 987 988 #ifdef FDDEBUG 989 printf("fdmotoroff: unit %d\n", sc->hwunit); 990 #endif 991 if ((sc->flags & FDF_MOTORON) == 0) 992 goto done; 993 /* 994 * if we have a timeout on a dma operation let fddmadone() 995 * deal with it. 996 */ 997 if (fdc_indma == sc) { 998 fddmadone(sc, 1); 999 goto done; 1000 } 1001 #ifdef FDDEBUG 1002 printf(" motor was on, turning off\n"); 1003 #endif 1004 1005 /* 1006 * flush cache if needed 1007 */ 1008 if (sc->flags & FDF_DIRTY) { 1009 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1010 #ifdef FDDEBUG 1011 printf(" flushing dirty buffer first\n"); 1012 #endif 1013 /* 1014 * if dma'ing done for now, fddone() will call us again 1015 */ 1016 if (fdc_indma) 1017 goto done; 1018 fddmastart(sc, sc->cachetrk); 1019 goto done; 1020 } 1021 1022 /* 1023 * if controller is busy just schedule us to be called back 1024 */ 1025 if (fdc_indma) { 1026 /* 1027 * someone else has the controller now 1028 * just set flag and let fddone() call us again. 1029 */ 1030 sc->flags |= FDF_MOTOROFF; 1031 goto done; 1032 } 1033 1034 #ifdef FDDEBUG 1035 printf(" hw turning unit off\n"); 1036 #endif 1037 1038 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1039 FDDESELECT(FDCUNITMASK); 1040 FDSETMOTOR(0); 1041 delay(1); 1042 FDSELECT(sc->unitmask); 1043 delay(4); 1044 FDDESELECT(sc->unitmask); 1045 delay(1); 1046 if (sc->flags & FDF_WMOTOROFF) 1047 wakeup(fdmotoroff); 1048 done: 1049 splx(s); 1050 } 1051 1052 /* 1053 * select drive seek to track exit with motor on. 1054 * fdsetpos(x, 0, 0) does calibrates the drive. 1055 */ 1056 void 1057 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1058 { 1059 int nstep, sdir, ondly, ncyl, nside; 1060 1061 FDDESELECT(FDCUNITMASK); 1062 FDSETMOTOR(1); 1063 delay(1); 1064 FDSELECT(sc->unitmask); 1065 delay(1); 1066 if ((sc->flags & FDF_MOTORON) == 0) { 1067 ondly = 0; 1068 while (FDTESTC(FDB_READY) == 0) { 1069 delay(1000); 1070 if (++ondly >= 1000) 1071 break; 1072 } 1073 } 1074 sc->flags |= FDF_MOTORON; 1075 1076 ncyl = trk / FDNHEADS; 1077 nside = trk % FDNHEADS; 1078 1079 if (sc->curcyl == ncyl && fdc_side == nside) 1080 return; 1081 1082 if (towrite) 1083 sc->flags |= FDF_WRITEWAIT; 1084 1085 #ifdef FDDEBUG 1086 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1087 trk % FDNHEADS, towrite); 1088 #endif 1089 nstep = ncyl - sc->curcyl; 1090 if (nstep) { 1091 /* 1092 * figure direction 1093 */ 1094 if (nstep > 0 && ncyl != 0) { 1095 sdir = FDSTEPIN; 1096 FDSETDIR(1); 1097 } else { 1098 nstep = -nstep; 1099 sdir = FDSTEPOUT; 1100 FDSETDIR(0); 1101 } 1102 if (ncyl == 0) { 1103 /* 1104 * either just want cylinder 0 or doing 1105 * a calibrate. 1106 */ 1107 nstep = 256; 1108 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1109 FDSTEP; 1110 delay(sc->stepdelay); 1111 } 1112 if (nstep < 0) 1113 sc->flags |= FDF_NOTRACK0; 1114 } else { 1115 /* 1116 * step the needed amount amount. 1117 */ 1118 while (nstep--) { 1119 FDSTEP; 1120 delay(sc->stepdelay); 1121 } 1122 } 1123 /* 1124 * if switched directions 1125 * allow drive to settle. 1126 */ 1127 if (sc->pstepdir != sdir) 1128 delay(FDSETTLEDELAY); 1129 sc->pstepdir = sdir; 1130 sc->curcyl = ncyl; 1131 } 1132 if (nside == fdc_side) 1133 return; 1134 /* 1135 * select side 1136 */ 1137 fdc_side = nside; 1138 FDSETHEAD(nside); 1139 delay(FDPRESIDEDELAY); 1140 } 1141 1142 void 1143 fdselunit(struct fd_softc *sc) 1144 { 1145 FDDESELECT(FDCUNITMASK); /* deselect all */ 1146 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1147 delay(1); 1148 FDSELECT(sc->unitmask); /* select unit */ 1149 delay(1); 1150 } 1151 1152 /* 1153 * process next buf on device queue. 1154 * normall sequence of events: 1155 * fdstart() -> fddmastart(); 1156 * fdidxintr(); 1157 * fdintr() -> fddmadone() -> fddone(); 1158 * if the track is in the cache then fdstart() will short-circuit 1159 * to fddone() else if the track cache is dirty it will flush. If 1160 * the buf is not an entire track it will cache the requested track. 1161 */ 1162 void 1163 fdstart(struct fd_softc *sc) 1164 { 1165 int trk, error, write; 1166 struct buf *bp, *dp; 1167 int changed; 1168 1169 #ifdef FDDEBUG 1170 printf("fdstart: unit %d\n", sc->hwunit); 1171 #endif 1172 1173 /* 1174 * if dma'ing just return. we must have been called from fdstartegy. 1175 */ 1176 if (fdc_indma) 1177 return; 1178 1179 /* 1180 * get next buf if there. 1181 */ 1182 dp = &sc->curbuf; 1183 if ((bp = BUFQ_FIRST(&sc->bufq)) == NULL) { 1184 #ifdef FDDEBUG 1185 printf(" nothing to do\n"); 1186 #endif 1187 return; 1188 } 1189 1190 /* 1191 * Mark us as busy now, in case fddone() gets called in one 1192 * of the cases below. 1193 */ 1194 disk_busy(&sc->dkdev); 1195 1196 /* 1197 * make sure same disk is loaded 1198 */ 1199 fdselunit(sc); 1200 changed = FDTESTC(FDB_CHANGED); 1201 FDDESELECT(sc->unitmask); 1202 if (changed) { 1203 /* 1204 * disk missing, invalidate all future io on 1205 * this unit until re-open()'ed also invalidate 1206 * all current io 1207 */ 1208 printf("fdstart: disk changed\n"); 1209 #ifdef FDDEBUG 1210 printf(" disk was removed invalidating all io\n"); 1211 #endif 1212 sc->flags &= ~FDF_HAVELABEL; 1213 for (;;) { 1214 bp->b_flags |= B_ERROR; 1215 bp->b_error = EIO; 1216 if (BUFQ_NEXT(bp) == NULL) 1217 break; 1218 biodone(bp); 1219 bp = BUFQ_NEXT(bp); 1220 } 1221 /* 1222 * do fddone() on last buf to allow other units to start. 1223 */ 1224 BUFQ_INSERT_HEAD(&sc->bufq, bp); 1225 fddone(sc); 1226 return; 1227 } 1228 1229 /* 1230 * we have a valid buf, setup our local version 1231 * we use this count to allow reading over multiple tracks. 1232 * into a single buffer 1233 */ 1234 dp->b_bcount = bp->b_bcount; 1235 dp->b_blkno = bp->b_blkno; 1236 dp->b_data = bp->b_data; 1237 dp->b_flags = bp->b_flags; 1238 dp->b_resid = 0; 1239 1240 if (bp->b_flags & B_READ) 1241 write = 0; 1242 else if (FDTESTC(FDB_PROTECT) == 0) 1243 write = 1; 1244 else { 1245 error = EPERM; 1246 goto bad; 1247 } 1248 1249 /* 1250 * figure trk given blkno 1251 */ 1252 trk = bp->b_blkno / sc->nsectors; 1253 1254 /* 1255 * check to see if same as currently cached track 1256 * if so we need to do no dma read. 1257 */ 1258 if (trk == sc->cachetrk) { 1259 fddone(sc); 1260 return; 1261 } 1262 1263 /* 1264 * if we will be overwriting the entire cache, don't bother to 1265 * fetch it. 1266 */ 1267 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1268 bp->b_blkno % sc->nsectors == 0) { 1269 if (sc->flags & FDF_DIRTY) 1270 sc->flags |= FDF_JUSTFLUSH; 1271 else { 1272 sc->cachetrk = trk; 1273 fddone(sc); 1274 return; 1275 } 1276 } 1277 1278 /* 1279 * start dma read of `trk' 1280 */ 1281 fddmastart(sc, trk); 1282 return; 1283 bad: 1284 bp->b_flags |= B_ERROR; 1285 bp->b_error = error; 1286 fddone(sc); 1287 } 1288 1289 /* 1290 * continue a started operation on next track. always begin at 1291 * sector 0 on the next track. 1292 */ 1293 void 1294 fdcont(struct fd_softc *sc) 1295 { 1296 struct buf *dp, *bp; 1297 int trk, write; 1298 1299 dp = &sc->curbuf; 1300 bp = BUFQ_FIRST(&sc->bufq); 1301 dp->b_data += (dp->b_bcount - bp->b_resid); 1302 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1303 dp->b_bcount = bp->b_resid; 1304 1305 /* 1306 * figure trk given blkno 1307 */ 1308 trk = dp->b_blkno / sc->nsectors; 1309 #ifdef DEBUG 1310 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1311 panic("fdcont: confused"); 1312 #endif 1313 if (dp->b_flags & B_READ) 1314 write = 0; 1315 else 1316 write = 1; 1317 /* 1318 * if we will be overwriting the entire cache, don't bother to 1319 * fetch it. 1320 */ 1321 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1322 if (sc->flags & FDF_DIRTY) 1323 sc->flags |= FDF_JUSTFLUSH; 1324 else { 1325 sc->cachetrk = trk; 1326 fddone(sc); 1327 return; 1328 } 1329 } 1330 /* 1331 * start dma read of `trk' 1332 */ 1333 fddmastart(sc, trk); 1334 return; 1335 } 1336 1337 void 1338 fddmastart(struct fd_softc *sc, int trk) 1339 { 1340 int adkmask, ndmaw, write, dmatrk; 1341 1342 #ifdef FDDEBUG 1343 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1344 trk / FDNHEADS, trk % FDNHEADS); 1345 #endif 1346 /* 1347 * flush the cached track if dirty else read requested track. 1348 */ 1349 if (sc->flags & FDF_DIRTY) { 1350 fdcachetoraw(sc); 1351 ndmaw = sc->type->nwritew; 1352 dmatrk = sc->cachetrk; 1353 write = 1; 1354 } else { 1355 ndmaw = sc->type->nreadw; 1356 dmatrk = trk; 1357 write = 0; 1358 } 1359 1360 #ifdef FDDEBUG 1361 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1362 #endif 1363 sc->cachetrk = trk; 1364 fdc_indma = sc; 1365 fdsetpos(sc, dmatrk, write); 1366 1367 /* 1368 * setup dma stuff 1369 */ 1370 if (write == 0) { 1371 custom.adkcon = ADKF_MSBSYNC; 1372 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1373 custom.dsksync = FDMFMSYNC; 1374 } else { 1375 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1376 ADKF_MSBSYNC; 1377 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1378 if (dmatrk >= sc->type->precomp[0]) 1379 adkmask |= ADKF_PRECOMP0; 1380 if (dmatrk >= sc->type->precomp[1]) 1381 adkmask |= ADKF_PRECOMP1; 1382 custom.adkcon = adkmask; 1383 } 1384 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1385 1386 /* 1387 * If writing an MSDOS track, activate disk index pulse 1388 * interrupt, dma will be started in the intr routine fdidxintr() 1389 * Otherwise, start the DMA here. 1390 */ 1391 if (write && sc->openpart == FDMSDOSPART) { 1392 fdc_dmalen = ndmaw; 1393 fdc_dmawrite = write; 1394 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1395 } else { 1396 FDDMASTART(ndmaw, write); 1397 fdc_dmalen = 0; 1398 } 1399 1400 #ifdef FDDEBUG 1401 printf(" dma started\n"); 1402 #endif 1403 } 1404 1405 /* 1406 * recalibrate the drive 1407 */ 1408 void 1409 fdcalibrate(void *arg) 1410 { 1411 struct fd_softc *sc; 1412 static int loopcnt; 1413 1414 sc = arg; 1415 1416 if (loopcnt == 0) { 1417 /* 1418 * seek cyl 0 1419 */ 1420 fdc_indma = sc; 1421 sc->stepdelay += 900; 1422 if (sc->cachetrk > 1) 1423 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1424 sc->stepdelay -= 900; 1425 } 1426 if (loopcnt++ & 1) 1427 fdsetpos(sc, sc->cachetrk, 0); 1428 else 1429 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1430 /* 1431 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and dma 1432 */ 1433 if (loopcnt < 8) 1434 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1435 else { 1436 loopcnt = 0; 1437 fdc_indma = NULL; 1438 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1439 fddmastart(sc, sc->cachetrk); 1440 } 1441 } 1442 1443 void 1444 fddmadone(struct fd_softc *sc, int timeo) 1445 { 1446 #ifdef FDDEBUG 1447 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1448 #endif 1449 fdc_indma = NULL; 1450 callout_stop(&sc->motor_ch); 1451 FDDMASTOP; 1452 1453 /* 1454 * guarantee the drive has been at current head and cyl 1455 * for at least FDWRITEDELAY after a write. 1456 */ 1457 if (sc->flags & FDF_WRITEWAIT) { 1458 delay(FDWRITEDELAY); 1459 sc->flags &= ~FDF_WRITEWAIT; 1460 } 1461 1462 if ((sc->flags & FDF_MOTOROFF) == 0) { 1463 /* 1464 * motor runs for 1.5 seconds after last dma 1465 */ 1466 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1467 } 1468 if (sc->flags & FDF_DIRTY) { 1469 /* 1470 * if buffer dirty, the last dma cleaned it 1471 */ 1472 sc->flags &= ~FDF_DIRTY; 1473 if (timeo) 1474 printf("%s: write of track cache timed out.\n", 1475 sc->sc_dv.dv_xname); 1476 if (sc->flags & FDF_JUSTFLUSH) { 1477 sc->flags &= ~FDF_JUSTFLUSH; 1478 /* 1479 * we are done dma'ing 1480 */ 1481 fddone(sc); 1482 return; 1483 } 1484 /* 1485 * load the cache 1486 */ 1487 fddmastart(sc, sc->cachetrk); 1488 return; 1489 } 1490 #ifdef FDDEBUG 1491 else if (sc->flags & FDF_MOTOROFF) 1492 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1493 #endif 1494 1495 /* 1496 * cache loaded decode it into cache buffer 1497 */ 1498 if (timeo == 0 && fdrawtocache(sc) == 0) 1499 sc->retried = 0; 1500 else { 1501 #ifdef FDDEBUG 1502 if (timeo) 1503 printf("%s: fddmadone: cache load timed out.\n", 1504 sc->sc_dv.dv_xname); 1505 #endif 1506 if (sc->retried >= sc->retries) { 1507 sc->retried = 0; 1508 sc->cachetrk = -1; 1509 } else { 1510 sc->retried++; 1511 /* 1512 * this will be restarted at end of calibrate loop. 1513 */ 1514 callout_stop(&sc->motor_ch); 1515 fdcalibrate(sc); 1516 return; 1517 } 1518 } 1519 fddone(sc); 1520 } 1521 1522 void 1523 fddone(struct fd_softc *sc) 1524 { 1525 struct buf *dp, *bp; 1526 char *data; 1527 int sz; 1528 1529 #ifdef FDDEBUG 1530 printf("fddone: unit %d\n", sc->hwunit); 1531 #endif 1532 /* 1533 * check to see if unit is just flushing the cache, 1534 * that is we have no io queued. 1535 */ 1536 if (sc->flags & FDF_MOTOROFF) 1537 goto nobuf; 1538 1539 dp = &sc->curbuf; 1540 if ((bp = BUFQ_FIRST(&sc->bufq)) == NULL) 1541 panic ("fddone"); 1542 /* 1543 * check for an error that may have occurred 1544 * while getting the track. 1545 */ 1546 if (sc->cachetrk == -1) { 1547 sc->retried = 0; 1548 bp->b_flags |= B_ERROR; 1549 bp->b_error = EIO; 1550 } else if ((bp->b_flags & B_ERROR) == 0) { 1551 data = sc->cachep; 1552 /* 1553 * get offset of data in track cache and limit 1554 * the copy size to not exceed the cache's end. 1555 */ 1556 data += (dp->b_blkno % sc->nsectors) * FDSECSIZE; 1557 sz = sc->nsectors - dp->b_blkno % sc->nsectors; 1558 sz *= FDSECSIZE; 1559 sz = min(dp->b_bcount, sz); 1560 if (bp->b_flags & B_READ) 1561 bcopy(data, dp->b_data, sz); 1562 else { 1563 bcopy(dp->b_data, data, sz); 1564 sc->flags |= FDF_DIRTY; 1565 } 1566 bp->b_resid = dp->b_bcount - sz; 1567 if (bp->b_resid == 0) { 1568 bp->b_error = 0; 1569 } else { 1570 /* 1571 * not done yet need to read next track 1572 */ 1573 fdcont(sc); 1574 return; 1575 } 1576 } 1577 /* 1578 * remove from queue. 1579 */ 1580 BUFQ_REMOVE(&sc->bufq, bp); 1581 1582 disk_unbusy(&sc->dkdev, (bp->b_bcount - bp->b_resid)); 1583 1584 biodone(bp); 1585 nobuf: 1586 fdfindwork(sc->sc_dv.dv_unit); 1587 } 1588 1589 void 1590 fdfindwork(int unit) 1591 { 1592 struct fd_softc *ssc, *sc; 1593 int i, last; 1594 1595 /* 1596 * first see if we have any fdopen()'s waiting 1597 */ 1598 if (fdc_wantwakeup) { 1599 wakeup(fdopen); 1600 fdc_wantwakeup--; 1601 return; 1602 } 1603 1604 /* 1605 * start next available unit, linear search from the next unit 1606 * wrapping and finally this unit. 1607 */ 1608 last = 0; 1609 ssc = NULL; 1610 for (i = unit + 1; last == 0; i++) { 1611 if (i == unit) 1612 last = 1; 1613 if (i >= fd_cd.cd_ndevs) { 1614 i = -1; 1615 continue; 1616 } 1617 if ((sc = fd_cd.cd_devs[i]) == NULL) 1618 continue; 1619 1620 /* 1621 * if unit has requested to be turned off 1622 * and it has no buf's queued do it now 1623 */ 1624 if (sc->flags & FDF_MOTOROFF) { 1625 if (BUFQ_FIRST(&sc->bufq) == NULL) 1626 fdmotoroff(sc); 1627 else { 1628 /* 1629 * we gained a buf request while 1630 * we waited, forget the motoroff 1631 */ 1632 sc->flags &= ~FDF_MOTOROFF; 1633 } 1634 /* 1635 * if we now have dma unit must have needed 1636 * flushing, quit 1637 */ 1638 if (fdc_indma) 1639 return; 1640 } 1641 /* 1642 * if we have no start unit and the current unit has 1643 * io waiting choose this unit to start. 1644 */ 1645 if (ssc == NULL && BUFQ_FIRST(&sc->bufq) != NULL) 1646 ssc = sc; 1647 } 1648 if (ssc) 1649 fdstart(ssc); 1650 } 1651 1652 /* 1653 * min byte count to whats left of the track in question 1654 */ 1655 void 1656 fdminphys(struct buf *bp) 1657 { 1658 struct fd_softc *sc; 1659 int trk, sec, toff, tsz; 1660 1661 if ((sc = getsoftc(fd_cd, FDUNIT(bp->b_dev))) == NULL) 1662 panic("fdminphys: couldn't get softc"); 1663 1664 trk = bp->b_blkno / sc->nsectors; 1665 sec = bp->b_blkno % sc->nsectors; 1666 1667 toff = sec * FDSECSIZE; 1668 tsz = sc->nsectors * FDSECSIZE; 1669 #ifdef FDDEBUG 1670 printf("fdminphys: before %d", bp->b_bcount); 1671 #endif 1672 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1673 #ifdef FDDEBUG 1674 printf(" after %d\n", bp->b_bcount); 1675 #endif 1676 minphys(bp); 1677 } 1678 1679 /* 1680 * encode the track cache into raw MFM ready for dma 1681 * when we go to multiple disk formats, this will call type dependent 1682 * functions 1683 */ 1684 void fdcachetoraw(struct fd_softc *sc) 1685 { 1686 if (sc->openpart == FDMSDOSPART) 1687 mscachetoraw(sc); 1688 else 1689 amcachetoraw(sc); 1690 } 1691 1692 /* 1693 * decode raw MFM from dma into units track cache. 1694 * when we go to multiple disk formats, this will call type dependent 1695 * functions 1696 */ 1697 int 1698 fdrawtocache(struct fd_softc *sc) 1699 { 1700 1701 if (sc->openpart == FDMSDOSPART) 1702 return(msrawtocache(sc)); 1703 else 1704 return(amrawtocache(sc)); 1705 } 1706 1707 void 1708 amcachetoraw(struct fd_softc *sc) 1709 { 1710 static u_long mfmnull[4]; 1711 u_long *rp, *crp, *dp, hcksum, dcksum, info, zero; 1712 int sec, i; 1713 1714 rp = fdc_dmap; 1715 1716 /* 1717 * not yet one sector (- 1 long) gap. 1718 * for now use previous drivers values 1719 */ 1720 for (i = 0; i < sc->type->gap; i++) 1721 *rp++ = 0xaaaaaaaa; 1722 /* 1723 * process sectors 1724 */ 1725 dp = sc->cachep; 1726 zero = 0; 1727 info = 0xff000000 | (sc->cachetrk << 16) | sc->nsectors; 1728 for (sec = 0; sec < sc->nsectors; sec++, info += (1 << 8) - 1) { 1729 hcksum = dcksum = 0; 1730 /* 1731 * sector format 1732 * offset description 1733 *----------------------------------- 1734 * 0 null 1735 * 1 sync 1736 * oddbits evenbits 1737 *---------------------- 1738 * 2 3 [0xff]b [trk]b [sec]b [togap]b 1739 * 4-7 8-11 null 1740 * 12 13 header cksum [2-11] 1741 * 14 15 data cksum [16-271] 1742 * 16-143 144-271 data 1743 */ 1744 *rp = 0xaaaaaaaa; 1745 if (*(rp - 1) & 0x1) 1746 *rp &= 0x7fffffff; /* clock bit correction */ 1747 rp++; 1748 *rp++ = (FDMFMSYNC << 16) | FDMFMSYNC; 1749 rp = mfmblkencode(&info, rp, &hcksum, 1); 1750 rp = mfmblkencode(mfmnull, rp, &hcksum, 4); 1751 rp = mfmblkencode(&hcksum, rp, NULL, 1); 1752 1753 crp = rp; 1754 rp = mfmblkencode(dp, rp + 2, &dcksum, FDSECLWORDS); 1755 dp += FDSECLWORDS; 1756 crp = mfmblkencode(&dcksum, crp, NULL, 1); 1757 if (*(crp - 1) & 0x1) 1758 *crp &= 0x7fffffff; /* clock bit correction */ 1759 else if ((*crp & 0x40000000) == 0) 1760 *crp |= 0x80000000; 1761 } 1762 *rp = 0xaaa80000; 1763 if (*(rp - 1) & 0x1) 1764 *rp &= 0x7fffffff; 1765 } 1766 1767 u_long * 1768 fdfindsync(u_long *rp, u_long *ep) 1769 { 1770 u_short *sp; 1771 1772 sp = (u_short *)rp; 1773 while ((u_long *)sp < ep && *sp != FDMFMSYNC) 1774 sp++; 1775 while ((u_long *)sp < ep && *sp == FDMFMSYNC) 1776 sp++; 1777 if ((u_long *)sp < ep) 1778 return((u_long *)sp); 1779 return(NULL); 1780 } 1781 1782 int 1783 amrawtocache(struct fd_softc *sc) 1784 { 1785 u_long mfmnull[4]; 1786 u_long *dp, *rp, *erp, *crp, *srp, hcksum, dcksum, info, cktmp; 1787 int cnt, doagain; 1788 1789 doagain = 1; 1790 srp = rp = fdc_dmap; 1791 erp = (u_long *)((u_short *)rp + sc->type->nreadw); 1792 cnt = 0; 1793 again: 1794 if (doagain == 0 || (rp = srp = fdfindsync(srp, erp)) == NULL) { 1795 #ifdef DIAGNOSTIC 1796 printf("%s: corrupted track (%d) data.\n", 1797 sc->sc_dv.dv_xname, sc->cachetrk); 1798 #endif 1799 return(-1); 1800 } 1801 1802 /* 1803 * process sectors 1804 */ 1805 for (; cnt < sc->nsectors; cnt++) { 1806 hcksum = dcksum = 0; 1807 rp = mfmblkdecode(rp, &info, &hcksum, 1); 1808 rp = mfmblkdecode(rp, mfmnull, &hcksum, 4); 1809 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1810 if (cktmp != hcksum) { 1811 #ifdef FDDEBUG 1812 printf(" info 0x%x hchksum 0x%x trkhcksum 0x%x\n", 1813 info, hcksum, cktmp); 1814 #endif 1815 goto again; 1816 } 1817 if (((info >> 16) & 0xff) != sc->cachetrk) { 1818 #ifdef DEBUG 1819 printf("%s: incorrect track found: 0x%lx %d\n", 1820 sc->sc_dv.dv_xname, info, sc->cachetrk); 1821 #endif 1822 goto again; 1823 } 1824 #ifdef FDDEBUG 1825 printf(" info 0x%x\n", info); 1826 #endif 1827 1828 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1829 dp = sc->cachep; 1830 dp += FDSECLWORDS * ((info >> 8) & 0xff); 1831 crp = mfmblkdecode(rp, dp, &dcksum, FDSECLWORDS); 1832 if (cktmp != dcksum) { 1833 #ifdef FDDEBUG 1834 printf(" info 0x%x dchksum 0x%x trkdcksum 0x%x\n", 1835 info, dcksum, cktmp); 1836 #endif 1837 goto again; 1838 } 1839 1840 /* 1841 * if we are at gap then we can no longer be sure 1842 * of correct sync marks 1843 */ 1844 if ((info && 0xff) == 1) 1845 doagain = 1; 1846 else 1847 doagain = 0; 1848 srp = rp = fdfindsync(crp, erp); 1849 } 1850 return(0); 1851 } 1852 1853 void 1854 mscachetoraw(struct fd_softc *sc) 1855 { 1856 u_short *rp, *erp, crc; 1857 u_char *cp, tb[5]; 1858 int sec, i; 1859 1860 rp = (u_short *)fdc_dmap; 1861 erp = rp + sc->type->nwritew; 1862 cp = sc->cachep; 1863 1864 /* 1865 * initial track filler (828 * GAP1) 1866 */ 1867 for (i = 0; i < sc->type->gap; i++) { 1868 *rp++ = FDMFMGAP1; 1869 *rp++ = FDMFMGAP1; 1870 } 1871 1872 for (sec = 0; sec < sc->nsectors; sec++) { 1873 1874 /* 1875 * leading sector gap 1876 * (12 * GAP2) + (3 * SYNC) 1877 */ 1878 for (i = 0; i < 12; i++) 1879 *rp++ = FDMFMGAP2; 1880 *rp++ = FDMFMSYNC; 1881 *rp++ = FDMFMSYNC; 1882 *rp++ = FDMFMSYNC; 1883 1884 /* 1885 * sector information 1886 * (ID) + track + side + sector + sector size + CRC16 1887 */ 1888 *rp++ = FDMFMID; 1889 tb[0] = sc->cachetrk / FDNHEADS; 1890 tb[1] = sc->cachetrk % FDNHEADS; 1891 tb[2] = sec + 1; 1892 i = sc->bytespersec; 1893 tb[3] = i < 256 ? 0 : (i < 512 ? 1 : (i < 1024 ? 2 : 3)); 1894 rp = msblkencode(rp, tb, 4, &crc); 1895 tb[0] = crc >> 8; 1896 tb[1] = crc & 0xff; 1897 tb[2] = 0x4e; /* GAP1 decoded */ 1898 rp = msblkencode(rp, tb, 3, 0); 1899 1900 /* 1901 * sector info/data gap 1902 * (22 * GAP1) + (12 * GAP2) + (3 * SYNC) 1903 */ 1904 for (i = 0; i < 21; i++) 1905 *rp++ = FDMFMGAP1; 1906 for (i = 0; i < 12; i++) 1907 *rp++ = FDMFMGAP2; 1908 *rp++ = FDMFMSYNC; 1909 *rp++ = FDMFMSYNC; 1910 *rp++ = FDMFMSYNC; 1911 1912 /* 1913 * sector data 1914 * (DATA) + ...data... + CRC16 1915 */ 1916 *rp++ = FDMFMDATA; 1917 rp = msblkencode(rp, cp, sc->bytespersec, &crc); 1918 cp += sc->bytespersec; 1919 tb[0] = crc >> 8; 1920 tb[1] = crc & 0xff; 1921 tb[2] = 0x4e; /* GAP3 decoded */ 1922 rp = msblkencode(rp, tb, 3, 0); 1923 1924 /* 1925 * trailing sector gap 1926 * (80 * GAP3) 1927 */ 1928 for (i = 0; i < 79; i++) 1929 *rp++ = FDMFMGAP3; 1930 } 1931 1932 /* 1933 * fill rest of track with GAP3 1934 */ 1935 while (rp != erp) 1936 *rp++ = FDMFMGAP3; 1937 1938 } 1939 1940 int 1941 msrawtocache(struct fd_softc *sc) 1942 { 1943 u_short *rp, *srp, *erp; 1944 u_char tb[5], *cp; 1945 int ct, sec, retry; 1946 1947 srp = rp = (u_short *)fdc_dmap; 1948 erp = rp + sc->type->nreadw; 1949 cp = sc->cachep; 1950 1951 for (ct = 0; ct < sc->nsectors; ct++) { 1952 retry = 1; 1953 do { 1954 /* 1955 * skip leading gap to sync 1956 */ 1957 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) { 1958 #ifdef DIAGNOSTIC 1959 printf("%s: corrupted track (%d) data.\n", 1960 sc->sc_dv.dv_xname, sc->cachetrk); 1961 #endif 1962 return(-1); 1963 } 1964 1965 /* 1966 * Grab sector info 1967 */ 1968 if (*rp++ != FDMFMID) 1969 continue; 1970 rp = msblkdecode(rp, tb, 4); 1971 #ifdef FDDEBUG 1972 printf("sector id: sector %d, track %d, side %d," 1973 "bps %d\n", tb[2], tb[0], tb[1], 128 << tb[3]); 1974 #endif 1975 if ((tb[0] * FDNHEADS + tb[1]) != sc->cachetrk || 1976 tb[2] > sc->nsectors) 1977 continue; 1978 1979 sec = tb[2]; 1980 sc->bytespersec = 128 << tb[3]; 1981 rp += 2; /* skip CRC-16 */ 1982 1983 /* 1984 * skip gap and read in data 1985 */ 1986 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) 1987 return(-1); 1988 if (*rp++ != FDMFMDATA) 1989 continue; 1990 rp = msblkdecode(rp, cp + ((sec-1) * sc->bytespersec), 1991 sc->bytespersec); 1992 rp += 2; /* skip CRC-16 */ 1993 1994 retry = 0; 1995 } while (retry); 1996 } 1997 return(0); 1998 } 1999 2000 /* 2001 * encode len longwords of `dp' data in amiga mfm block format (`rp') 2002 * this format specified that the odd bits are at current pos and even 2003 * bits at len + current pos 2004 */ 2005 u_long * 2006 mfmblkencode(u_long *dp, u_long *rp, u_long *cp, int len) 2007 { 2008 u_long *sdp, *edp, d, dtmp, correct; 2009 2010 sdp = dp; 2011 edp = dp + len; 2012 2013 if (*(rp - 1) & 0x1) 2014 correct = 1; 2015 else 2016 correct = 0; 2017 /* 2018 * do odd bits 2019 */ 2020 while (dp < edp) { 2021 d = (*dp >> 1) & 0x55555555; /* remove clock bits */ 2022 dtmp = d ^ 0x55555555; 2023 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2024 /* 2025 * correct upper clock bit if needed 2026 */ 2027 if (correct) 2028 d &= 0x7fffffff; 2029 if (d & 0x1) 2030 correct = 1; 2031 else 2032 correct = 0; 2033 /* 2034 * do checksums and store in raw buffer 2035 */ 2036 if (cp) 2037 *cp ^= d; 2038 *rp++ = d; 2039 dp++; 2040 } 2041 /* 2042 * do even bits 2043 */ 2044 dp = sdp; 2045 while (dp < edp) { 2046 d = *dp & 0x55555555; /* remove clock bits */ 2047 dtmp = d ^ 0x55555555; 2048 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2049 /* 2050 * correct upper clock bit if needed 2051 */ 2052 if (correct) 2053 d &= 0x7fffffff; 2054 if (d & 0x1) 2055 correct = 1; 2056 else 2057 correct = 0; 2058 /* 2059 * do checksums and store in raw buffer 2060 */ 2061 if (cp) 2062 *cp ^= d; 2063 *rp++ = d; 2064 dp++; 2065 } 2066 if (cp) 2067 *cp &= 0x55555555; 2068 return(rp); 2069 } 2070 2071 /* 2072 * decode len longwords of `dp' data in amiga mfm block format (`rp') 2073 * this format specified that the odd bits are at current pos and even 2074 * bits at len + current pos 2075 */ 2076 u_long * 2077 mfmblkdecode(u_long *rp, u_long *dp, u_long *cp, int len) 2078 { 2079 u_long o, e; 2080 int cnt; 2081 2082 cnt = len; 2083 while (cnt--) { 2084 o = *rp; 2085 e = *(rp + len); 2086 if (cp) { 2087 *cp ^= o; 2088 *cp ^= e; 2089 } 2090 o &= 0x55555555; 2091 e &= 0x55555555; 2092 *dp++ = (o << 1) | e; 2093 rp++; 2094 } 2095 if (cp) 2096 *cp &= 0x55555555; 2097 return(rp + len); 2098 } 2099 2100 /* 2101 * decode len words in standard MFM format to len bytes 2102 * of data. 2103 */ 2104 u_short * 2105 msblkdecode(u_short *rp, u_char *cp, int len) 2106 { 2107 while (len--) { 2108 *cp++ = msdecode[*rp & 0x7f] | 2109 (msdecode[(*rp >> 8) & 0x7f] << 4); 2110 rp++; 2111 } 2112 2113 return(rp); 2114 } 2115 2116 /* 2117 * encode len bytes of data into len words in standard MFM format. 2118 * If a pointer is supplied for crc, calculate the CRC-16 of the data 2119 * as well. 2120 */ 2121 u_short * 2122 msblkencode(u_short *rp, u_char *cp, int len, u_short *crc) 2123 { 2124 u_short td; 2125 u_short mycrc; 2126 2127 /* preload crc for header (4 bytes) 2128 * or data (anything else) 2129 */ 2130 mycrc = (len == 4) ? 0xb230 : 0xe295; 2131 2132 while (len--) { 2133 td = (msencode[*cp >> 4] << 8) | msencode[*cp & 0x0f]; 2134 2135 /* Check for zeros in top bit of encode and bottom 2136 * bit of previous encode. if so, slap a one in betweem 2137 * them. 2138 */ 2139 if ((td & 0x140) == 0) 2140 td |= 0x80; 2141 if ((td & 0x4000) == 0 && (rp[-1] & 1) == 0) 2142 td |= 0x8000; 2143 2144 *rp++ = td; 2145 2146 /* 2147 * calc crc if requested 2148 */ 2149 if (crc) 2150 mycrc = (mycrc << 8) ^ mscrctab[*cp ^ (mycrc >> 8)]; 2151 2152 cp++; 2153 } 2154 2155 if (crc) 2156 *crc = mycrc; 2157 2158 return(rp); 2159 } 2160
Indexes created Thu Oct 02 14:10:14 GMT 2025