fd.c revision 1.56
1 /* $NetBSD: fd.c,v 1.56 2002/11/01 11:31:51 mrg 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 1.56 2002/11/01 11:31:51 mrg 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 bufq_state 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 CFATTACH_DECL(fd, sizeof(struct fd_softc), 243 fdmatch, fdattach, NULL, NULL); 244 245 extern struct cfdriver fd_cd; 246 247 dev_type_open(fdopen); 248 dev_type_close(fdclose); 249 dev_type_read(fdread); 250 dev_type_write(fdwrite); 251 dev_type_ioctl(fdioctl); 252 dev_type_strategy(fdstrategy); 253 254 const struct bdevsw fd_bdevsw = { 255 fdopen, fdclose, fdstrategy, fdioctl, nodump, nosize, D_DISK 256 }; 257 258 const struct cdevsw fd_cdevsw = { 259 fdopen, fdclose, fdread, fdwrite, fdioctl, 260 nostop, notty, nopoll, nommap, nokqfilter, D_DISK 261 }; 262 263 struct dkdriver fddkdriver = { fdstrategy }; 264 265 CFATTACH_DECL(fdc, sizeof(struct device), 266 fdcmatch, fdcattach, NULL, NULL); 267 268 /* 269 * all hw access through macros, this helps to hide the active low 270 * properties 271 */ 272 273 #define FDUNITMASK(unit) (1 << (3 + (unit))) 274 275 /* 276 * select units using mask 277 */ 278 #define FDSELECT(um) do { ciab.prb &= ~(um); } while (0) 279 280 /* 281 * deselect units using mask 282 */ 283 #define FDDESELECT(um) do { ciab.prb |= (um); delay(1); } while (0) 284 285 /* 286 * test hw condition bits 287 */ 288 #define FDTESTC(bit) ((ciaa.pra & (1 << (bit))) == 0) 289 290 /* 291 * set motor for select units, true motor on else off 292 */ 293 #define FDSETMOTOR(on) do { \ 294 if (on) ciab.prb &= ~CIAB_PRB_MTR; else ciab.prb |= CIAB_PRB_MTR; \ 295 } while (0) 296 297 /* 298 * set head for select units 299 */ 300 #define FDSETHEAD(head) do { \ 301 if (head) ciab.prb &= ~CIAB_PRB_SIDE; else ciab.prb |= CIAB_PRB_SIDE; \ 302 delay(1); } while (0) 303 304 /* 305 * select direction, true towards spindle else outwards 306 */ 307 #define FDSETDIR(in) do { \ 308 if (in) ciab.prb &= ~CIAB_PRB_DIR; else ciab.prb |= CIAB_PRB_DIR; \ 309 delay(1); } while (0) 310 311 /* 312 * step the selected units 313 */ 314 #define FDSTEP do { \ 315 ciab.prb &= ~CIAB_PRB_STEP; ciab.prb |= CIAB_PRB_STEP; \ 316 } while (0) 317 318 #define FDDMASTART(len, towrite) do { \ 319 int dmasz = (len) | ((towrite) ? DISKLEN_WRITE : 0) | DISKLEN_DMAEN; \ 320 custom.dsklen = dmasz; custom.dsklen = dmasz; } while (0) 321 322 #define FDDMASTOP do { custom.dsklen = 0; } while (0) 323 324 325 int 326 fdcmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 327 { 328 static int fdc_matched = 0; 329 330 /* Allow only once instance. */ 331 if (matchname("fdc", auxp) == 0 || fdc_matched) 332 return(0); 333 if ((fdc_dmap = alloc_chipmem(DMABUFSZ)) == NULL) { 334 printf("fdc: unable to allocate dma buffer\n"); 335 return(0); 336 } 337 338 fdc_matched = 1; 339 return(1); 340 } 341 342 void 343 fdcattach(struct device *pdp, struct device *dp, void *auxp) 344 { 345 struct fdcargs args; 346 347 printf(": dmabuf pa 0x%x", kvtop(fdc_dmap)); 348 printf(": dmabuf ka %p\n", fdc_dmap); 349 args.unit = 0; 350 args.type = fdcgetfdtype(args.unit); 351 352 fdc_side = -1; 353 config_found(dp, &args, fdcprint); 354 for (args.unit++; args.unit < FDMAXUNITS; args.unit++) { 355 if ((args.type = fdcgetfdtype(args.unit)) == NULL) 356 continue; 357 config_found(dp, &args, fdcprint); 358 } 359 } 360 361 int 362 fdcprint(void *auxp, const char *pnp) 363 { 364 struct fdcargs *fcp; 365 366 fcp = auxp; 367 if (pnp) 368 printf("fd%d at %s unit %d:", fcp->unit, pnp, 369 fcp->type->driveid); 370 return(UNCONF); 371 } 372 373 /*ARGSUSED*/ 374 int 375 fdmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 376 { 377 struct fdcargs *fdap; 378 379 fdap = auxp; 380 if (cfp->cf_loc[FDCCF_UNIT] == fdap->unit || 381 cfp->cf_loc[FDCCF_UNIT] == FDCCF_UNIT_DEFAULT) 382 return(1); 383 384 return(0); 385 } 386 387 void 388 fdattach(struct device *pdp, struct device *dp, void *auxp) 389 { 390 struct fdcargs *ap; 391 struct fd_softc *sc; 392 int i; 393 394 ap = auxp; 395 sc = (struct fd_softc *)dp; 396 397 bufq_alloc(&sc->bufq, BUFQ_DISKSORT|BUFQ_SORT_CYLINDER); 398 callout_init(&sc->calibrate_ch); 399 callout_init(&sc->motor_ch); 400 401 sc->curcyl = sc->cachetrk = -1; 402 sc->openpart = -1; 403 sc->type = ap->type; 404 sc->hwunit = ap->unit; 405 sc->unitmask = 1 << (3 + ap->unit); 406 sc->retries = FDRETRIES; 407 sc->stepdelay = FDSTEPDELAY; 408 sc->bytespersec = 512; 409 printf(" unit %d: %s %d cyl, %d head, %d sec [%d sec], 512 bytes/sec\n", 410 sc->hwunit, sc->type->desc, sc->type->ncylinders, FDNHEADS, 411 sc->type->amiga_nsectors, sc->type->msdos_nsectors); 412 413 /* 414 * Initialize and attach the disk structure. 415 */ 416 sc->dkdev.dk_name = sc->sc_dv.dv_xname; 417 sc->dkdev.dk_driver = &fddkdriver; 418 disk_attach(&sc->dkdev); 419 420 /* 421 * calibrate the drive 422 */ 423 fdsetpos(sc, 0, 0); 424 fdsetpos(sc, sc->type->ncylinders, 0); 425 fdsetpos(sc, 0, 0); 426 fdmotoroff(sc); 427 428 /* 429 * precalc msdos MFM and CRC 430 */ 431 for (i = 0; i < 128; i++) 432 msdecode[i] = 0xff; 433 for (i = 0; i < 16; i++) 434 msdecode[msencode[i]] = i; 435 for (i = 0; i < 256; i++) { 436 mscrctab[i] = (0x1021 * (i & 0xf0)) ^ (0x1021 * (i & 0x0f)) ^ 437 (0x1021 * (i >> 4)); 438 } 439 440 /* 441 * enable disk related interrupts 442 */ 443 custom.dmacon = DMAF_SETCLR | DMAF_MASTER | DMAF_DISK; 444 custom.intena = INTF_SETCLR | INTF_DSKBLK; 445 ciab.icr = CIA_ICR_FLG; 446 } 447 448 /*ARGSUSED*/ 449 int 450 fdopen(dev_t dev, int flags, int devtype, struct proc *p) 451 { 452 struct fd_softc *sc; 453 int wasopen, fwork, error, s; 454 455 error = 0; 456 457 if (FDPART(dev) >= FDMAXPARTS) 458 return(ENXIO); 459 460 if ((sc = getsoftc(fd_cd, FDUNIT(dev))) == NULL) 461 return(ENXIO); 462 if (sc->flags & FDF_NOTRACK0) 463 return(ENXIO); 464 if (sc->cachep == NULL) 465 sc->cachep = malloc(MAXTRKSZ, M_DEVBUF, M_WAITOK); 466 467 s = splbio(); 468 /* 469 * if we are sleeping in fdclose(); waiting for a chance to 470 * shut the motor off, do a sleep here also. 471 */ 472 while (sc->flags & FDF_WMOTOROFF) 473 tsleep(fdmotoroff, PRIBIO, "fdopen", 0); 474 475 fwork = 0; 476 /* 477 * if not open let user open request type, otherwise 478 * ensure they are trying to open same type. 479 */ 480 if (sc->openpart == FDPART(dev)) 481 wasopen = 1; 482 else if (sc->openpart == -1) { 483 sc->openpart = FDPART(dev); 484 wasopen = 0; 485 } else { 486 wasopen = 1; 487 error = EPERM; 488 goto done; 489 } 490 491 /* 492 * wait for current io to complete if any 493 */ 494 if (fdc_indma) { 495 fwork = 1; 496 fdc_wantwakeup++; 497 tsleep(fdopen, PRIBIO, "fdopen", 0); 498 } 499 if ((error = fdloaddisk(sc)) != 0) 500 goto done; 501 if ((error = fdgetdisklabel(sc, dev)) != 0) 502 goto done; 503 #ifdef FDDEBUG 504 printf(" open successful\n"); 505 #endif 506 done: 507 /* 508 * if we requested that fddone()->fdfindwork() wake us, allow it to 509 * complete its job now 510 */ 511 if (fwork) 512 fdfindwork(FDUNIT(dev)); 513 splx(s); 514 515 /* 516 * if we were not open and we marked us so reverse that. 517 */ 518 if (error && wasopen == 0) 519 sc->openpart = -1; 520 return(error); 521 } 522 523 /*ARGSUSED*/ 524 int 525 fdclose(dev_t dev, int flags, int devtype, struct proc *p) 526 { 527 struct fd_softc *sc; 528 int s; 529 530 #ifdef FDDEBUG 531 printf("fdclose()\n"); 532 #endif 533 sc = getsoftc(fd_cd, FDUNIT(dev)); 534 s = splbio(); 535 if (sc->flags & FDF_MOTORON) { 536 sc->flags |= FDF_WMOTOROFF; 537 tsleep(fdmotoroff, PRIBIO, "fdclose", 0); 538 sc->flags &= ~FDF_WMOTOROFF; 539 wakeup(fdmotoroff); 540 } 541 sc->openpart = -1; 542 splx(s); 543 return(0); 544 } 545 546 int 547 fdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) 548 { 549 struct fd_softc *sc; 550 int error, wlab; 551 552 sc = getsoftc(fd_cd, FDUNIT(dev)); 553 554 if ((sc->flags & FDF_HAVELABEL) == 0) 555 return(EBADF); 556 557 switch (cmd) { 558 case DIOCSBAD: 559 return(EINVAL); 560 case DIOCSRETRIES: 561 if (*(int *)addr < 0) 562 return(EINVAL); 563 sc->retries = *(int *)addr; 564 return(0); 565 case DIOCSSTEP: 566 if (*(int *)addr < FDSTEPDELAY) 567 return(EINVAL); 568 sc->dkdev.dk_label->d_trkseek = sc->stepdelay = *(int *)addr; 569 return(0); 570 case DIOCGDINFO: 571 *(struct disklabel *)addr = *(sc->dkdev.dk_label); 572 return(0); 573 case DIOCGPART: 574 ((struct partinfo *)addr)->disklab = sc->dkdev.dk_label; 575 ((struct partinfo *)addr)->part = 576 &sc->dkdev.dk_label->d_partitions[FDPART(dev)]; 577 return(0); 578 case DIOCSDINFO: 579 if ((flag & FWRITE) == 0) 580 return(EBADF); 581 return(fdsetdisklabel(sc, (struct disklabel *)addr)); 582 case DIOCWDINFO: 583 if ((flag & FWRITE) == 0) 584 return(EBADF); 585 if ((error = fdsetdisklabel(sc, (struct disklabel *)addr)) != 0) 586 return(error); 587 wlab = sc->wlabel; 588 sc->wlabel = 1; 589 error = fdputdisklabel(sc, dev); 590 sc->wlabel = wlab; 591 return(error); 592 case DIOCWLABEL: 593 if ((flag & FWRITE) == 0) 594 return(EBADF); 595 sc->wlabel = *(int *)addr; 596 return(0); 597 case DIOCGDEFLABEL: 598 fdgetdefaultlabel(sc, (struct disklabel *)addr, FDPART(dev)); 599 return(0); 600 default: 601 return(ENOTTY); 602 } 603 } 604 605 int 606 fdread(dev_t dev, struct uio *uio, int flags) 607 { 608 return (physio(fdstrategy, NULL, dev, B_READ, fdminphys, uio)); 609 } 610 611 int 612 fdwrite(dev_t dev, struct uio *uio, int flags) 613 { 614 return (physio(fdstrategy, NULL, dev, B_WRITE, fdminphys, uio)); 615 } 616 617 618 void 619 fdintr(int flag) 620 { 621 int s; 622 623 s = splbio(); 624 if (fdc_indma) 625 fddmadone(fdc_indma, 0); 626 splx(s); 627 } 628 629 void 630 fdidxintr(void) 631 { 632 if (fdc_indma && fdc_dmalen) { 633 /* 634 * turn off intr and start actual dma 635 */ 636 ciab.icr = CIA_ICR_FLG; 637 FDDMASTART(fdc_dmalen, fdc_dmawrite); 638 fdc_dmalen = 0; 639 } 640 } 641 642 void 643 fdstrategy(struct buf *bp) 644 { 645 struct disklabel *lp; 646 struct fd_softc *sc; 647 int unit, part, s; 648 649 unit = FDUNIT(bp->b_dev); 650 part = FDPART(bp->b_dev); 651 sc = getsoftc(fd_cd, unit); 652 653 #ifdef FDDEBUG 654 printf("fdstrategy: 0x%x\n", bp); 655 #endif 656 /* 657 * check for valid partition and bounds 658 */ 659 lp = sc->dkdev.dk_label; 660 if ((sc->flags & FDF_HAVELABEL) == 0) { 661 bp->b_error = EIO; 662 goto bad; 663 } 664 if (bounds_check_with_label(bp, lp, sc->wlabel) <= 0) 665 goto done; 666 667 /* 668 * trans count of zero or bounds check indicates io is done 669 * we are done. 670 */ 671 if (bp->b_bcount == 0) 672 goto done; 673 674 bp->b_rawblkno = bp->b_blkno; 675 676 /* 677 * queue the buf and kick the low level code 678 */ 679 s = splbio(); 680 BUFQ_PUT(&sc->bufq, bp); 681 fdstart(sc); 682 splx(s); 683 return; 684 bad: 685 bp->b_flags |= B_ERROR; 686 done: 687 bp->b_resid = bp->b_bcount; 688 biodone(bp); 689 } 690 691 /* 692 * make sure disk is loaded and label is up-to-date. 693 */ 694 int 695 fdloaddisk(struct fd_softc *sc) 696 { 697 /* 698 * if diskchange is low step drive to 0 then up one then to zero. 699 */ 700 fdselunit(sc); /* make sure the unit is selected */ 701 if (FDTESTC(FDB_CHANGED)) { 702 fdsetpos(sc, 0, 0); 703 sc->cachetrk = -1; /* invalidate the cache */ 704 sc->flags &= ~FDF_HAVELABEL; 705 fdsetpos(sc, FDNHEADS, 0); 706 fdsetpos(sc, 0, 0); 707 if (FDTESTC(FDB_CHANGED)) { 708 fdmotoroff(sc); 709 FDDESELECT(sc->unitmask); 710 return(ENXIO); 711 } 712 } 713 FDDESELECT(sc->unitmask); 714 fdmotoroff(sc); 715 sc->type = fdcgetfdtype(sc->hwunit); 716 if (sc->type == NULL) 717 return(ENXIO); 718 if (sc->openpart == FDMSDOSPART) 719 sc->nsectors = sc->type->msdos_nsectors; 720 else 721 sc->nsectors = sc->type->amiga_nsectors; 722 return(0); 723 } 724 725 void 726 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 727 /* (variable part) XXX ick */ 728 { 729 730 bzero(lp, sizeof(struct disklabel)); 731 lp->d_secsize = FDSECSIZE; 732 lp->d_ntracks = FDNHEADS; 733 lp->d_ncylinders = sc->type->ncylinders; 734 lp->d_nsectors = sc->nsectors; 735 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 736 lp->d_type = DTYPE_FLOPPY; 737 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 738 lp->d_rpm = 300; /* good guess I suppose. */ 739 lp->d_interleave = 1; /* should change when adding msdos */ 740 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 741 lp->d_bbsize = 0; 742 lp->d_sbsize = 0; 743 lp->d_partitions[part].p_size = lp->d_secperunit; 744 lp->d_partitions[part].p_fstype = FS_UNUSED; 745 lp->d_partitions[part].p_fsize = 1024; 746 lp->d_partitions[part].p_frag = 8; 747 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 748 lp->d_npartitions = part + 1; 749 lp->d_magic = lp->d_magic2 = DISKMAGIC; 750 lp->d_checksum = dkcksum(lp); 751 } 752 753 /* 754 * read disk label, if present otherwise create one 755 * return a new label if raw part and none found, otherwise err. 756 */ 757 int 758 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 759 { 760 struct disklabel *lp, *dlp; 761 struct cpu_disklabel *clp; 762 struct buf *bp; 763 int error, part; 764 765 if (sc->flags & FDF_HAVELABEL && 766 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 767 return(0); 768 #ifdef FDDEBUG 769 printf("fdgetdisklabel()\n"); 770 #endif 771 part = FDPART(dev); 772 lp = sc->dkdev.dk_label; 773 clp = sc->dkdev.dk_cpulabel; 774 bzero(lp, sizeof(struct disklabel)); 775 bzero(clp, sizeof(struct cpu_disklabel)); 776 777 lp->d_secsize = FDSECSIZE; 778 lp->d_ntracks = FDNHEADS; 779 lp->d_ncylinders = sc->type->ncylinders; 780 lp->d_nsectors = sc->nsectors; 781 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 782 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 783 lp->d_npartitions = part + 1; 784 lp->d_partitions[part].p_size = lp->d_secperunit; 785 lp->d_partitions[part].p_fstype = FS_UNUSED; 786 lp->d_partitions[part].p_fsize = 1024; 787 lp->d_partitions[part].p_frag = 8; 788 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 789 790 sc->flags |= FDF_HAVELABEL; 791 792 bp = (void *)geteblk((int)lp->d_secsize); 793 bp->b_dev = dev; 794 bp->b_blkno = 0; 795 bp->b_cylinder = 0; 796 bp->b_bcount = FDSECSIZE; 797 bp->b_flags |= B_READ; 798 fdstrategy(bp); 799 if ((error = biowait(bp)) != 0) 800 goto nolabel; 801 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 802 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 803 dkcksum(dlp)) { 804 error = EINVAL; 805 goto nolabel; 806 } 807 bcopy(dlp, lp, sizeof(struct disklabel)); 808 if (lp->d_trkseek > FDSTEPDELAY) 809 sc->stepdelay = lp->d_trkseek; 810 brelse(bp); 811 return(0); 812 nolabel: 813 fdgetdefaultlabel(sc, lp, part); 814 brelse(bp); 815 return(0); 816 } 817 818 /* 819 * set the incore copy of this units disklabel 820 */ 821 int 822 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 823 { 824 struct disklabel *clp; 825 struct partition *pp; 826 827 /* 828 * must have at least opened raw unit to fetch the 829 * raw_part stuff. 830 */ 831 if ((sc->flags & FDF_HAVELABEL) == 0) 832 return(EINVAL); 833 clp = sc->dkdev.dk_label; 834 /* 835 * make sure things check out and we only have one valid 836 * partition 837 */ 838 #ifdef FDDEBUG 839 printf("fdsetdisklabel\n"); 840 #endif 841 if (lp->d_secsize != FDSECSIZE || 842 lp->d_nsectors != clp->d_nsectors || 843 lp->d_ntracks != FDNHEADS || 844 lp->d_ncylinders != clp->d_ncylinders || 845 lp->d_secpercyl != clp->d_secpercyl || 846 lp->d_secperunit != clp->d_secperunit || 847 lp->d_magic != DISKMAGIC || 848 lp->d_magic2 != DISKMAGIC || 849 lp->d_npartitions == 0 || 850 lp->d_npartitions > FDMAXPARTS || 851 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 852 dkcksum(lp)) 853 return(EINVAL); 854 /* 855 * if any partitions are present make sure they 856 * represent the currently open type 857 */ 858 if ((pp = &lp->d_partitions[0])->p_size) { 859 if ((pp = &lp->d_partitions[1])->p_size == 0) 860 goto done; 861 else if (sc->openpart != 1) 862 return(EINVAL); 863 } else if (sc->openpart != 0) 864 return(EINVAL); 865 /* 866 * make sure selected partition is within bounds 867 * XXX on the second check, its to handle a bug in 868 * XXX the cluster routines as they require mutliples 869 * XXX of NBPG currently 870 */ 871 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 872 (pp->p_frag * pp->p_fsize % NBPG)) 873 return(EINVAL); 874 done: 875 bcopy(lp, clp, sizeof(struct disklabel)); 876 return(0); 877 } 878 879 /* 880 * write out the incore copy of this units disklabel 881 */ 882 int 883 fdputdisklabel(struct fd_softc *sc, dev_t dev) 884 { 885 struct disklabel *lp, *dlp; 886 struct buf *bp; 887 int error; 888 889 if ((sc->flags & FDF_HAVELABEL) == 0) 890 return(EBADF); 891 #ifdef FDDEBUG 892 printf("fdputdisklabel\n"); 893 #endif 894 /* 895 * get buf and read in sector 0 896 */ 897 lp = sc->dkdev.dk_label; 898 bp = geteblk((int)lp->d_secsize); 899 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 900 bp->b_blkno = 0; 901 bp->b_cylinder = 0; 902 bp->b_bcount = FDSECSIZE; 903 bp->b_flags |= B_READ; 904 fdstrategy(bp); 905 if ((error = biowait(bp)) != 0) 906 goto done; 907 /* 908 * copy disklabel to buf and write it out syncronous 909 */ 910 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 911 bcopy(lp, dlp, sizeof(struct disklabel)); 912 bp->b_blkno = 0; 913 bp->b_cylinder = 0; 914 bp->b_flags &= ~(B_READ|B_DONE); 915 bp->b_flags |= B_WRITE; 916 fdstrategy(bp); 917 error = biowait(bp); 918 done: 919 brelse(bp); 920 return(error); 921 } 922 923 /* 924 * figure out drive type or NULL if none. 925 */ 926 struct fdtype * 927 fdcgetfdtype(int unit) 928 { 929 struct fdtype *ftp; 930 u_long id, idb; 931 int cnt, umask; 932 933 id = 0; 934 umask = 1 << (3 + unit); 935 936 FDDESELECT(FDCUNITMASK); 937 938 FDSETMOTOR(1); 939 delay(1); 940 FDSELECT(umask); 941 delay(1); 942 FDDESELECT(umask); 943 944 FDSETMOTOR(0); 945 delay(1); 946 FDSELECT(umask); 947 delay(1); 948 FDDESELECT(umask); 949 950 for (idb = 0x80000000; idb; idb >>= 1) { 951 FDSELECT(umask); 952 delay(1); 953 if (FDTESTC(FDB_READY) == 0) 954 id |= idb; 955 FDDESELECT(umask); 956 delay(1); 957 } 958 #ifdef FDDEBUG 959 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 960 #endif 961 962 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 963 if (ftp->driveid == id) 964 return(ftp); 965 /* 966 * 3.5dd's at unit 0 do not always return id. 967 */ 968 if (unit == 0) 969 return(fdtype); 970 return(NULL); 971 } 972 973 /* 974 * turn motor off if possible otherwise mark as needed and will be done 975 * later. 976 */ 977 void 978 fdmotoroff(void *arg) 979 { 980 struct fd_softc *sc; 981 int s; 982 983 sc = arg; 984 s = splbio(); 985 986 #ifdef FDDEBUG 987 printf("fdmotoroff: unit %d\n", sc->hwunit); 988 #endif 989 if ((sc->flags & FDF_MOTORON) == 0) 990 goto done; 991 /* 992 * if we have a timeout on a dma operation let fddmadone() 993 * deal with it. 994 */ 995 if (fdc_indma == sc) { 996 fddmadone(sc, 1); 997 goto done; 998 } 999 #ifdef FDDEBUG 1000 printf(" motor was on, turning off\n"); 1001 #endif 1002 1003 /* 1004 * flush cache if needed 1005 */ 1006 if (sc->flags & FDF_DIRTY) { 1007 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1008 #ifdef FDDEBUG 1009 printf(" flushing dirty buffer first\n"); 1010 #endif 1011 /* 1012 * if dma'ing done for now, fddone() will call us again 1013 */ 1014 if (fdc_indma) 1015 goto done; 1016 fddmastart(sc, sc->cachetrk); 1017 goto done; 1018 } 1019 1020 /* 1021 * if controller is busy just schedule us to be called back 1022 */ 1023 if (fdc_indma) { 1024 /* 1025 * someone else has the controller now 1026 * just set flag and let fddone() call us again. 1027 */ 1028 sc->flags |= FDF_MOTOROFF; 1029 goto done; 1030 } 1031 1032 #ifdef FDDEBUG 1033 printf(" hw turning unit off\n"); 1034 #endif 1035 1036 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1037 FDDESELECT(FDCUNITMASK); 1038 FDSETMOTOR(0); 1039 delay(1); 1040 FDSELECT(sc->unitmask); 1041 delay(4); 1042 FDDESELECT(sc->unitmask); 1043 delay(1); 1044 if (sc->flags & FDF_WMOTOROFF) 1045 wakeup(fdmotoroff); 1046 done: 1047 splx(s); 1048 } 1049 1050 /* 1051 * select drive seek to track exit with motor on. 1052 * fdsetpos(x, 0, 0) does calibrates the drive. 1053 */ 1054 void 1055 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1056 { 1057 int nstep, sdir, ondly, ncyl, nside; 1058 1059 FDDESELECT(FDCUNITMASK); 1060 FDSETMOTOR(1); 1061 delay(1); 1062 FDSELECT(sc->unitmask); 1063 delay(1); 1064 if ((sc->flags & FDF_MOTORON) == 0) { 1065 ondly = 0; 1066 while (FDTESTC(FDB_READY) == 0) { 1067 delay(1000); 1068 if (++ondly >= 1000) 1069 break; 1070 } 1071 } 1072 sc->flags |= FDF_MOTORON; 1073 1074 ncyl = trk / FDNHEADS; 1075 nside = trk % FDNHEADS; 1076 1077 if (sc->curcyl == ncyl && fdc_side == nside) 1078 return; 1079 1080 if (towrite) 1081 sc->flags |= FDF_WRITEWAIT; 1082 1083 #ifdef FDDEBUG 1084 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1085 trk % FDNHEADS, towrite); 1086 #endif 1087 nstep = ncyl - sc->curcyl; 1088 if (nstep) { 1089 /* 1090 * figure direction 1091 */ 1092 if (nstep > 0 && ncyl != 0) { 1093 sdir = FDSTEPIN; 1094 FDSETDIR(1); 1095 } else { 1096 nstep = -nstep; 1097 sdir = FDSTEPOUT; 1098 FDSETDIR(0); 1099 } 1100 if (ncyl == 0) { 1101 /* 1102 * either just want cylinder 0 or doing 1103 * a calibrate. 1104 */ 1105 nstep = 256; 1106 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1107 FDSTEP; 1108 delay(sc->stepdelay); 1109 } 1110 if (nstep < 0) 1111 sc->flags |= FDF_NOTRACK0; 1112 } else { 1113 /* 1114 * step the needed amount amount. 1115 */ 1116 while (nstep--) { 1117 FDSTEP; 1118 delay(sc->stepdelay); 1119 } 1120 } 1121 /* 1122 * if switched directions 1123 * allow drive to settle. 1124 */ 1125 if (sc->pstepdir != sdir) 1126 delay(FDSETTLEDELAY); 1127 sc->pstepdir = sdir; 1128 sc->curcyl = ncyl; 1129 } 1130 if (nside == fdc_side) 1131 return; 1132 /* 1133 * select side 1134 */ 1135 fdc_side = nside; 1136 FDSETHEAD(nside); 1137 delay(FDPRESIDEDELAY); 1138 } 1139 1140 void 1141 fdselunit(struct fd_softc *sc) 1142 { 1143 FDDESELECT(FDCUNITMASK); /* deselect all */ 1144 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1145 delay(1); 1146 FDSELECT(sc->unitmask); /* select unit */ 1147 delay(1); 1148 } 1149 1150 /* 1151 * process next buf on device queue. 1152 * normall sequence of events: 1153 * fdstart() -> fddmastart(); 1154 * fdidxintr(); 1155 * fdintr() -> fddmadone() -> fddone(); 1156 * if the track is in the cache then fdstart() will short-circuit 1157 * to fddone() else if the track cache is dirty it will flush. If 1158 * the buf is not an entire track it will cache the requested track. 1159 */ 1160 void 1161 fdstart(struct fd_softc *sc) 1162 { 1163 int trk, error, write; 1164 struct buf *bp, *dp; 1165 int changed; 1166 1167 #ifdef FDDEBUG 1168 printf("fdstart: unit %d\n", sc->hwunit); 1169 #endif 1170 1171 /* 1172 * if dma'ing just return. we must have been called from fdstartegy. 1173 */ 1174 if (fdc_indma) 1175 return; 1176 1177 /* 1178 * get next buf if there. 1179 */ 1180 dp = &sc->curbuf; 1181 if ((bp = BUFQ_PEEK(&sc->bufq)) == NULL) { 1182 #ifdef FDDEBUG 1183 printf(" nothing to do\n"); 1184 #endif 1185 return; 1186 } 1187 1188 /* 1189 * Mark us as busy now, in case fddone() gets called in one 1190 * of the cases below. 1191 */ 1192 disk_busy(&sc->dkdev); 1193 1194 /* 1195 * make sure same disk is loaded 1196 */ 1197 fdselunit(sc); 1198 changed = FDTESTC(FDB_CHANGED); 1199 FDDESELECT(sc->unitmask); 1200 if (changed) { 1201 /* 1202 * disk missing, invalidate all future io on 1203 * this unit until re-open()'ed also invalidate 1204 * all current io 1205 */ 1206 printf("fdstart: disk changed\n"); 1207 #ifdef FDDEBUG 1208 printf(" disk was removed invalidating all io\n"); 1209 #endif 1210 sc->flags &= ~FDF_HAVELABEL; 1211 for (;;) { 1212 bp = BUFQ_GET(&sc->bufq); 1213 bp->b_flags |= B_ERROR; 1214 bp->b_error = EIO; 1215 if (BUFQ_PEEK(&sc->bufq) == NULL) 1216 break; 1217 biodone(bp); 1218 } 1219 /* 1220 * do fddone() on last buf to allow other units to start. 1221 */ 1222 BUFQ_PUT(&sc->bufq, bp); 1223 fddone(sc); 1224 return; 1225 } 1226 1227 /* 1228 * we have a valid buf, setup our local version 1229 * we use this count to allow reading over multiple tracks. 1230 * into a single buffer 1231 */ 1232 dp->b_bcount = bp->b_bcount; 1233 dp->b_blkno = bp->b_blkno; 1234 dp->b_data = bp->b_data; 1235 dp->b_flags = bp->b_flags; 1236 dp->b_resid = 0; 1237 1238 if (bp->b_flags & B_READ) 1239 write = 0; 1240 else if (FDTESTC(FDB_PROTECT) == 0) 1241 write = 1; 1242 else { 1243 error = EPERM; 1244 goto bad; 1245 } 1246 1247 /* 1248 * figure trk given blkno 1249 */ 1250 trk = bp->b_blkno / sc->nsectors; 1251 1252 /* 1253 * check to see if same as currently cached track 1254 * if so we need to do no dma read. 1255 */ 1256 if (trk == sc->cachetrk) { 1257 fddone(sc); 1258 return; 1259 } 1260 1261 /* 1262 * if we will be overwriting the entire cache, don't bother to 1263 * fetch it. 1264 */ 1265 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1266 bp->b_blkno % sc->nsectors == 0) { 1267 if (sc->flags & FDF_DIRTY) 1268 sc->flags |= FDF_JUSTFLUSH; 1269 else { 1270 sc->cachetrk = trk; 1271 fddone(sc); 1272 return; 1273 } 1274 } 1275 1276 /* 1277 * start dma read of `trk' 1278 */ 1279 fddmastart(sc, trk); 1280 return; 1281 bad: 1282 bp->b_flags |= B_ERROR; 1283 bp->b_error = error; 1284 fddone(sc); 1285 } 1286 1287 /* 1288 * continue a started operation on next track. always begin at 1289 * sector 0 on the next track. 1290 */ 1291 void 1292 fdcont(struct fd_softc *sc) 1293 { 1294 struct buf *dp, *bp; 1295 int trk, write; 1296 1297 dp = &sc->curbuf; 1298 bp = BUFQ_PEEK(&sc->bufq); 1299 dp->b_data += (dp->b_bcount - bp->b_resid); 1300 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1301 dp->b_bcount = bp->b_resid; 1302 1303 /* 1304 * figure trk given blkno 1305 */ 1306 trk = dp->b_blkno / sc->nsectors; 1307 #ifdef DEBUG 1308 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1309 panic("fdcont: confused"); 1310 #endif 1311 if (dp->b_flags & B_READ) 1312 write = 0; 1313 else 1314 write = 1; 1315 /* 1316 * if we will be overwriting the entire cache, don't bother to 1317 * fetch it. 1318 */ 1319 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1320 if (sc->flags & FDF_DIRTY) 1321 sc->flags |= FDF_JUSTFLUSH; 1322 else { 1323 sc->cachetrk = trk; 1324 fddone(sc); 1325 return; 1326 } 1327 } 1328 /* 1329 * start dma read of `trk' 1330 */ 1331 fddmastart(sc, trk); 1332 return; 1333 } 1334 1335 void 1336 fddmastart(struct fd_softc *sc, int trk) 1337 { 1338 int adkmask, ndmaw, write, dmatrk; 1339 1340 #ifdef FDDEBUG 1341 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1342 trk / FDNHEADS, trk % FDNHEADS); 1343 #endif 1344 /* 1345 * flush the cached track if dirty else read requested track. 1346 */ 1347 if (sc->flags & FDF_DIRTY) { 1348 fdcachetoraw(sc); 1349 ndmaw = sc->type->nwritew; 1350 dmatrk = sc->cachetrk; 1351 write = 1; 1352 } else { 1353 ndmaw = sc->type->nreadw; 1354 dmatrk = trk; 1355 write = 0; 1356 } 1357 1358 #ifdef FDDEBUG 1359 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1360 #endif 1361 sc->cachetrk = trk; 1362 fdc_indma = sc; 1363 fdsetpos(sc, dmatrk, write); 1364 1365 /* 1366 * setup dma stuff 1367 */ 1368 if (write == 0) { 1369 custom.adkcon = ADKF_MSBSYNC; 1370 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1371 custom.dsksync = FDMFMSYNC; 1372 } else { 1373 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1374 ADKF_MSBSYNC; 1375 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1376 if (dmatrk >= sc->type->precomp[0]) 1377 adkmask |= ADKF_PRECOMP0; 1378 if (dmatrk >= sc->type->precomp[1]) 1379 adkmask |= ADKF_PRECOMP1; 1380 custom.adkcon = adkmask; 1381 } 1382 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1383 1384 /* 1385 * If writing an MSDOS track, activate disk index pulse 1386 * interrupt, dma will be started in the intr routine fdidxintr() 1387 * Otherwise, start the DMA here. 1388 */ 1389 if (write && sc->openpart == FDMSDOSPART) { 1390 fdc_dmalen = ndmaw; 1391 fdc_dmawrite = write; 1392 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1393 } else { 1394 FDDMASTART(ndmaw, write); 1395 fdc_dmalen = 0; 1396 } 1397 1398 #ifdef FDDEBUG 1399 printf(" dma started\n"); 1400 #endif 1401 } 1402 1403 /* 1404 * recalibrate the drive 1405 */ 1406 void 1407 fdcalibrate(void *arg) 1408 { 1409 struct fd_softc *sc; 1410 static int loopcnt; 1411 1412 sc = arg; 1413 1414 if (loopcnt == 0) { 1415 /* 1416 * seek cyl 0 1417 */ 1418 fdc_indma = sc; 1419 sc->stepdelay += 900; 1420 if (sc->cachetrk > 1) 1421 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1422 sc->stepdelay -= 900; 1423 } 1424 if (loopcnt++ & 1) 1425 fdsetpos(sc, sc->cachetrk, 0); 1426 else 1427 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1428 /* 1429 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and dma 1430 */ 1431 if (loopcnt < 8) 1432 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1433 else { 1434 loopcnt = 0; 1435 fdc_indma = NULL; 1436 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1437 fddmastart(sc, sc->cachetrk); 1438 } 1439 } 1440 1441 void 1442 fddmadone(struct fd_softc *sc, int timeo) 1443 { 1444 #ifdef FDDEBUG 1445 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1446 #endif 1447 fdc_indma = NULL; 1448 callout_stop(&sc->motor_ch); 1449 FDDMASTOP; 1450 1451 /* 1452 * guarantee the drive has been at current head and cyl 1453 * for at least FDWRITEDELAY after a write. 1454 */ 1455 if (sc->flags & FDF_WRITEWAIT) { 1456 delay(FDWRITEDELAY); 1457 sc->flags &= ~FDF_WRITEWAIT; 1458 } 1459 1460 if ((sc->flags & FDF_MOTOROFF) == 0) { 1461 /* 1462 * motor runs for 1.5 seconds after last dma 1463 */ 1464 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1465 } 1466 if (sc->flags & FDF_DIRTY) { 1467 /* 1468 * if buffer dirty, the last dma cleaned it 1469 */ 1470 sc->flags &= ~FDF_DIRTY; 1471 if (timeo) 1472 printf("%s: write of track cache timed out.\n", 1473 sc->sc_dv.dv_xname); 1474 if (sc->flags & FDF_JUSTFLUSH) { 1475 sc->flags &= ~FDF_JUSTFLUSH; 1476 /* 1477 * we are done dma'ing 1478 */ 1479 fddone(sc); 1480 return; 1481 } 1482 /* 1483 * load the cache 1484 */ 1485 fddmastart(sc, sc->cachetrk); 1486 return; 1487 } 1488 #ifdef FDDEBUG 1489 else if (sc->flags & FDF_MOTOROFF) 1490 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1491 #endif 1492 1493 /* 1494 * cache loaded decode it into cache buffer 1495 */ 1496 if (timeo == 0 && fdrawtocache(sc) == 0) 1497 sc->retried = 0; 1498 else { 1499 #ifdef FDDEBUG 1500 if (timeo) 1501 printf("%s: fddmadone: cache load timed out.\n", 1502 sc->sc_dv.dv_xname); 1503 #endif 1504 if (sc->retried >= sc->retries) { 1505 sc->retried = 0; 1506 sc->cachetrk = -1; 1507 } else { 1508 sc->retried++; 1509 /* 1510 * this will be restarted at end of calibrate loop. 1511 */ 1512 callout_stop(&sc->motor_ch); 1513 fdcalibrate(sc); 1514 return; 1515 } 1516 } 1517 fddone(sc); 1518 } 1519 1520 void 1521 fddone(struct fd_softc *sc) 1522 { 1523 struct buf *dp, *bp; 1524 char *data; 1525 int sz; 1526 1527 #ifdef FDDEBUG 1528 printf("fddone: unit %d\n", sc->hwunit); 1529 #endif 1530 /* 1531 * check to see if unit is just flushing the cache, 1532 * that is we have no io queued. 1533 */ 1534 if (sc->flags & FDF_MOTOROFF) 1535 goto nobuf; 1536 1537 dp = &sc->curbuf; 1538 if ((bp = BUFQ_PEEK(&sc->bufq)) == NULL) 1539 panic ("fddone"); 1540 /* 1541 * check for an error that may have occurred 1542 * while getting the track. 1543 */ 1544 if (sc->cachetrk == -1) { 1545 sc->retried = 0; 1546 bp->b_flags |= B_ERROR; 1547 bp->b_error = EIO; 1548 } else if ((bp->b_flags & B_ERROR) == 0) { 1549 data = sc->cachep; 1550 /* 1551 * get offset of data in track cache and limit 1552 * the copy size to not exceed the cache's end. 1553 */ 1554 data += (dp->b_blkno % sc->nsectors) * FDSECSIZE; 1555 sz = sc->nsectors - dp->b_blkno % sc->nsectors; 1556 sz *= FDSECSIZE; 1557 sz = min(dp->b_bcount, sz); 1558 if (bp->b_flags & B_READ) 1559 bcopy(data, dp->b_data, sz); 1560 else { 1561 bcopy(dp->b_data, data, sz); 1562 sc->flags |= FDF_DIRTY; 1563 } 1564 bp->b_resid = dp->b_bcount - sz; 1565 if (bp->b_resid == 0) { 1566 bp->b_error = 0; 1567 } else { 1568 /* 1569 * not done yet need to read next track 1570 */ 1571 fdcont(sc); 1572 return; 1573 } 1574 } 1575 /* 1576 * remove from queue. 1577 */ 1578 (void)BUFQ_GET(&sc->bufq); 1579 1580 disk_unbusy(&sc->dkdev, (bp->b_bcount - bp->b_resid), 1581 (bp->b_flags & B_READ)); 1582 1583 biodone(bp); 1584 nobuf: 1585 fdfindwork(sc->sc_dv.dv_unit); 1586 } 1587 1588 void 1589 fdfindwork(int unit) 1590 { 1591 struct fd_softc *ssc, *sc; 1592 int i, last; 1593 1594 /* 1595 * first see if we have any fdopen()'s waiting 1596 */ 1597 if (fdc_wantwakeup) { 1598 wakeup(fdopen); 1599 fdc_wantwakeup--; 1600 return; 1601 } 1602 1603 /* 1604 * start next available unit, linear search from the next unit 1605 * wrapping and finally this unit. 1606 */ 1607 last = 0; 1608 ssc = NULL; 1609 for (i = unit + 1; last == 0; i++) { 1610 if (i == unit) 1611 last = 1; 1612 if (i >= fd_cd.cd_ndevs) { 1613 i = -1; 1614 continue; 1615 } 1616 if ((sc = fd_cd.cd_devs[i]) == NULL) 1617 continue; 1618 1619 /* 1620 * if unit has requested to be turned off 1621 * and it has no buf's queued do it now 1622 */ 1623 if (sc->flags & FDF_MOTOROFF) { 1624 if (BUFQ_PEEK(&sc->bufq) == NULL) 1625 fdmotoroff(sc); 1626 else { 1627 /* 1628 * we gained a buf request while 1629 * we waited, forget the motoroff 1630 */ 1631 sc->flags &= ~FDF_MOTOROFF; 1632 } 1633 /* 1634 * if we now have dma unit must have needed 1635 * flushing, quit 1636 */ 1637 if (fdc_indma) 1638 return; 1639 } 1640 /* 1641 * if we have no start unit and the current unit has 1642 * io waiting choose this unit to start. 1643 */ 1644 if (ssc == NULL && BUFQ_PEEK(&sc->bufq) != NULL) 1645 ssc = sc; 1646 } 1647 if (ssc) 1648 fdstart(ssc); 1649 } 1650 1651 /* 1652 * min byte count to whats left of the track in question 1653 */ 1654 void 1655 fdminphys(struct buf *bp) 1656 { 1657 struct fd_softc *sc; 1658 int trk, sec, toff, tsz; 1659 1660 if ((sc = getsoftc(fd_cd, FDUNIT(bp->b_dev))) == NULL) 1661 panic("fdminphys: couldn't get softc"); 1662 1663 trk = bp->b_blkno / sc->nsectors; 1664 sec = bp->b_blkno % sc->nsectors; 1665 1666 toff = sec * FDSECSIZE; 1667 tsz = sc->nsectors * FDSECSIZE; 1668 #ifdef FDDEBUG 1669 printf("fdminphys: before %d", bp->b_bcount); 1670 #endif 1671 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1672 #ifdef FDDEBUG 1673 printf(" after %d\n", bp->b_bcount); 1674 #endif 1675 minphys(bp); 1676 } 1677 1678 /* 1679 * encode the track cache into raw MFM ready for dma 1680 * when we go to multiple disk formats, this will call type dependent 1681 * functions 1682 */ 1683 void fdcachetoraw(struct fd_softc *sc) 1684 { 1685 if (sc->openpart == FDMSDOSPART) 1686 mscachetoraw(sc); 1687 else 1688 amcachetoraw(sc); 1689 } 1690 1691 /* 1692 * decode raw MFM from dma into units track cache. 1693 * when we go to multiple disk formats, this will call type dependent 1694 * functions 1695 */ 1696 int 1697 fdrawtocache(struct fd_softc *sc) 1698 { 1699 1700 if (sc->openpart == FDMSDOSPART) 1701 return(msrawtocache(sc)); 1702 else 1703 return(amrawtocache(sc)); 1704 } 1705 1706 void 1707 amcachetoraw(struct fd_softc *sc) 1708 { 1709 static u_long mfmnull[4]; 1710 u_long *rp, *crp, *dp, hcksum, dcksum, info, zero; 1711 int sec, i; 1712 1713 rp = fdc_dmap; 1714 1715 /* 1716 * not yet one sector (- 1 long) gap. 1717 * for now use previous drivers values 1718 */ 1719 for (i = 0; i < sc->type->gap; i++) 1720 *rp++ = 0xaaaaaaaa; 1721 /* 1722 * process sectors 1723 */ 1724 dp = sc->cachep; 1725 zero = 0; 1726 info = 0xff000000 | (sc->cachetrk << 16) | sc->nsectors; 1727 for (sec = 0; sec < sc->nsectors; sec++, info += (1 << 8) - 1) { 1728 hcksum = dcksum = 0; 1729 /* 1730 * sector format 1731 * offset description 1732 *----------------------------------- 1733 * 0 null 1734 * 1 sync 1735 * oddbits evenbits 1736 *---------------------- 1737 * 2 3 [0xff]b [trk]b [sec]b [togap]b 1738 * 4-7 8-11 null 1739 * 12 13 header cksum [2-11] 1740 * 14 15 data cksum [16-271] 1741 * 16-143 144-271 data 1742 */ 1743 *rp = 0xaaaaaaaa; 1744 if (*(rp - 1) & 0x1) 1745 *rp &= 0x7fffffff; /* clock bit correction */ 1746 rp++; 1747 *rp++ = (FDMFMSYNC << 16) | FDMFMSYNC; 1748 rp = mfmblkencode(&info, rp, &hcksum, 1); 1749 rp = mfmblkencode(mfmnull, rp, &hcksum, 4); 1750 rp = mfmblkencode(&hcksum, rp, NULL, 1); 1751 1752 crp = rp; 1753 rp = mfmblkencode(dp, rp + 2, &dcksum, FDSECLWORDS); 1754 dp += FDSECLWORDS; 1755 crp = mfmblkencode(&dcksum, crp, NULL, 1); 1756 if (*(crp - 1) & 0x1) 1757 *crp &= 0x7fffffff; /* clock bit correction */ 1758 else if ((*crp & 0x40000000) == 0) 1759 *crp |= 0x80000000; 1760 } 1761 *rp = 0xaaa80000; 1762 if (*(rp - 1) & 0x1) 1763 *rp &= 0x7fffffff; 1764 } 1765 1766 u_long * 1767 fdfindsync(u_long *rp, u_long *ep) 1768 { 1769 u_short *sp; 1770 1771 sp = (u_short *)rp; 1772 while ((u_long *)sp < ep && *sp != FDMFMSYNC) 1773 sp++; 1774 while ((u_long *)sp < ep && *sp == FDMFMSYNC) 1775 sp++; 1776 if ((u_long *)sp < ep) 1777 return((u_long *)sp); 1778 return(NULL); 1779 } 1780 1781 int 1782 amrawtocache(struct fd_softc *sc) 1783 { 1784 u_long mfmnull[4]; 1785 u_long *dp, *rp, *erp, *crp, *srp, hcksum, dcksum, info, cktmp; 1786 int cnt, doagain; 1787 1788 doagain = 1; 1789 srp = rp = fdc_dmap; 1790 erp = (u_long *)((u_short *)rp + sc->type->nreadw); 1791 cnt = 0; 1792 again: 1793 if (doagain == 0 || (rp = srp = fdfindsync(srp, erp)) == NULL) { 1794 #ifdef DIAGNOSTIC 1795 printf("%s: corrupted track (%d) data.\n", 1796 sc->sc_dv.dv_xname, sc->cachetrk); 1797 #endif 1798 return(-1); 1799 } 1800 1801 /* 1802 * process sectors 1803 */ 1804 for (; cnt < sc->nsectors; cnt++) { 1805 hcksum = dcksum = 0; 1806 rp = mfmblkdecode(rp, &info, &hcksum, 1); 1807 rp = mfmblkdecode(rp, mfmnull, &hcksum, 4); 1808 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1809 if (cktmp != hcksum) { 1810 #ifdef FDDEBUG 1811 printf(" info 0x%x hchksum 0x%x trkhcksum 0x%x\n", 1812 info, hcksum, cktmp); 1813 #endif 1814 goto again; 1815 } 1816 if (((info >> 16) & 0xff) != sc->cachetrk) { 1817 #ifdef DEBUG 1818 printf("%s: incorrect track found: 0x%lx %d\n", 1819 sc->sc_dv.dv_xname, info, sc->cachetrk); 1820 #endif 1821 goto again; 1822 } 1823 #ifdef FDDEBUG 1824 printf(" info 0x%x\n", info); 1825 #endif 1826 1827 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1828 dp = sc->cachep; 1829 dp += FDSECLWORDS * ((info >> 8) & 0xff); 1830 crp = mfmblkdecode(rp, dp, &dcksum, FDSECLWORDS); 1831 if (cktmp != dcksum) { 1832 #ifdef FDDEBUG 1833 printf(" info 0x%x dchksum 0x%x trkdcksum 0x%x\n", 1834 info, dcksum, cktmp); 1835 #endif 1836 goto again; 1837 } 1838 1839 /* 1840 * if we are at gap then we can no longer be sure 1841 * of correct sync marks 1842 */ 1843 if ((info && 0xff) == 1) 1844 doagain = 1; 1845 else 1846 doagain = 0; 1847 srp = rp = fdfindsync(crp, erp); 1848 } 1849 return(0); 1850 } 1851 1852 void 1853 mscachetoraw(struct fd_softc *sc) 1854 { 1855 u_short *rp, *erp, crc; 1856 u_char *cp, tb[5]; 1857 int sec, i; 1858 1859 rp = (u_short *)fdc_dmap; 1860 erp = rp + sc->type->nwritew; 1861 cp = sc->cachep; 1862 1863 /* 1864 * initial track filler (828 * GAP1) 1865 */ 1866 for (i = 0; i < sc->type->gap; i++) { 1867 *rp++ = FDMFMGAP1; 1868 *rp++ = FDMFMGAP1; 1869 } 1870 1871 for (sec = 0; sec < sc->nsectors; sec++) { 1872 1873 /* 1874 * leading sector gap 1875 * (12 * GAP2) + (3 * SYNC) 1876 */ 1877 for (i = 0; i < 12; i++) 1878 *rp++ = FDMFMGAP2; 1879 *rp++ = FDMFMSYNC; 1880 *rp++ = FDMFMSYNC; 1881 *rp++ = FDMFMSYNC; 1882 1883 /* 1884 * sector information 1885 * (ID) + track + side + sector + sector size + CRC16 1886 */ 1887 *rp++ = FDMFMID; 1888 tb[0] = sc->cachetrk / FDNHEADS; 1889 tb[1] = sc->cachetrk % FDNHEADS; 1890 tb[2] = sec + 1; 1891 i = sc->bytespersec; 1892 tb[3] = i < 256 ? 0 : (i < 512 ? 1 : (i < 1024 ? 2 : 3)); 1893 rp = msblkencode(rp, tb, 4, &crc); 1894 tb[0] = crc >> 8; 1895 tb[1] = crc & 0xff; 1896 tb[2] = 0x4e; /* GAP1 decoded */ 1897 rp = msblkencode(rp, tb, 3, 0); 1898 1899 /* 1900 * sector info/data gap 1901 * (22 * GAP1) + (12 * GAP2) + (3 * SYNC) 1902 */ 1903 for (i = 0; i < 21; i++) 1904 *rp++ = FDMFMGAP1; 1905 for (i = 0; i < 12; i++) 1906 *rp++ = FDMFMGAP2; 1907 *rp++ = FDMFMSYNC; 1908 *rp++ = FDMFMSYNC; 1909 *rp++ = FDMFMSYNC; 1910 1911 /* 1912 * sector data 1913 * (DATA) + ...data... + CRC16 1914 */ 1915 *rp++ = FDMFMDATA; 1916 rp = msblkencode(rp, cp, sc->bytespersec, &crc); 1917 cp += sc->bytespersec; 1918 tb[0] = crc >> 8; 1919 tb[1] = crc & 0xff; 1920 tb[2] = 0x4e; /* GAP3 decoded */ 1921 rp = msblkencode(rp, tb, 3, 0); 1922 1923 /* 1924 * trailing sector gap 1925 * (80 * GAP3) 1926 */ 1927 for (i = 0; i < 79; i++) 1928 *rp++ = FDMFMGAP3; 1929 } 1930 1931 /* 1932 * fill rest of track with GAP3 1933 */ 1934 while (rp != erp) 1935 *rp++ = FDMFMGAP3; 1936 1937 } 1938 1939 int 1940 msrawtocache(struct fd_softc *sc) 1941 { 1942 u_short *rp, *srp, *erp; 1943 u_char tb[5], *cp; 1944 int ct, sec, retry; 1945 1946 srp = rp = (u_short *)fdc_dmap; 1947 erp = rp + sc->type->nreadw; 1948 cp = sc->cachep; 1949 1950 for (ct = 0; ct < sc->nsectors; ct++) { 1951 retry = 1; 1952 do { 1953 /* 1954 * skip leading gap to sync 1955 */ 1956 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) { 1957 #ifdef DIAGNOSTIC 1958 printf("%s: corrupted track (%d) data.\n", 1959 sc->sc_dv.dv_xname, sc->cachetrk); 1960 #endif 1961 return(-1); 1962 } 1963 1964 /* 1965 * Grab sector info 1966 */ 1967 if (*rp++ != FDMFMID) 1968 continue; 1969 rp = msblkdecode(rp, tb, 4); 1970 #ifdef FDDEBUG 1971 printf("sector id: sector %d, track %d, side %d," 1972 "bps %d\n", tb[2], tb[0], tb[1], 128 << tb[3]); 1973 #endif 1974 if ((tb[0] * FDNHEADS + tb[1]) != sc->cachetrk || 1975 tb[2] > sc->nsectors) 1976 continue; 1977 1978 sec = tb[2]; 1979 sc->bytespersec = 128 << tb[3]; 1980 rp += 2; /* skip CRC-16 */ 1981 1982 /* 1983 * skip gap and read in data 1984 */ 1985 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) 1986 return(-1); 1987 if (*rp++ != FDMFMDATA) 1988 continue; 1989 rp = msblkdecode(rp, cp + ((sec-1) * sc->bytespersec), 1990 sc->bytespersec); 1991 rp += 2; /* skip CRC-16 */ 1992 1993 retry = 0; 1994 } while (retry); 1995 } 1996 return(0); 1997 } 1998 1999 /* 2000 * encode len longwords of `dp' data in amiga mfm block format (`rp') 2001 * this format specified that the odd bits are at current pos and even 2002 * bits at len + current pos 2003 */ 2004 u_long * 2005 mfmblkencode(u_long *dp, u_long *rp, u_long *cp, int len) 2006 { 2007 u_long *sdp, *edp, d, dtmp, correct; 2008 2009 sdp = dp; 2010 edp = dp + len; 2011 2012 if (*(rp - 1) & 0x1) 2013 correct = 1; 2014 else 2015 correct = 0; 2016 /* 2017 * do odd bits 2018 */ 2019 while (dp < edp) { 2020 d = (*dp >> 1) & 0x55555555; /* remove clock bits */ 2021 dtmp = d ^ 0x55555555; 2022 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2023 /* 2024 * correct upper clock bit if needed 2025 */ 2026 if (correct) 2027 d &= 0x7fffffff; 2028 if (d & 0x1) 2029 correct = 1; 2030 else 2031 correct = 0; 2032 /* 2033 * do checksums and store in raw buffer 2034 */ 2035 if (cp) 2036 *cp ^= d; 2037 *rp++ = d; 2038 dp++; 2039 } 2040 /* 2041 * do even bits 2042 */ 2043 dp = sdp; 2044 while (dp < edp) { 2045 d = *dp & 0x55555555; /* remove clock bits */ 2046 dtmp = d ^ 0x55555555; 2047 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2048 /* 2049 * correct upper clock bit if needed 2050 */ 2051 if (correct) 2052 d &= 0x7fffffff; 2053 if (d & 0x1) 2054 correct = 1; 2055 else 2056 correct = 0; 2057 /* 2058 * do checksums and store in raw buffer 2059 */ 2060 if (cp) 2061 *cp ^= d; 2062 *rp++ = d; 2063 dp++; 2064 } 2065 if (cp) 2066 *cp &= 0x55555555; 2067 return(rp); 2068 } 2069 2070 /* 2071 * decode len longwords of `dp' data in amiga mfm block format (`rp') 2072 * this format specified that the odd bits are at current pos and even 2073 * bits at len + current pos 2074 */ 2075 u_long * 2076 mfmblkdecode(u_long *rp, u_long *dp, u_long *cp, int len) 2077 { 2078 u_long o, e; 2079 int cnt; 2080 2081 cnt = len; 2082 while (cnt--) { 2083 o = *rp; 2084 e = *(rp + len); 2085 if (cp) { 2086 *cp ^= o; 2087 *cp ^= e; 2088 } 2089 o &= 0x55555555; 2090 e &= 0x55555555; 2091 *dp++ = (o << 1) | e; 2092 rp++; 2093 } 2094 if (cp) 2095 *cp &= 0x55555555; 2096 return(rp + len); 2097 } 2098 2099 /* 2100 * decode len words in standard MFM format to len bytes 2101 * of data. 2102 */ 2103 u_short * 2104 msblkdecode(u_short *rp, u_char *cp, int len) 2105 { 2106 while (len--) { 2107 *cp++ = msdecode[*rp & 0x7f] | 2108 (msdecode[(*rp >> 8) & 0x7f] << 4); 2109 rp++; 2110 } 2111 2112 return(rp); 2113 } 2114 2115 /* 2116 * encode len bytes of data into len words in standard MFM format. 2117 * If a pointer is supplied for crc, calculate the CRC-16 of the data 2118 * as well. 2119 */ 2120 u_short * 2121 msblkencode(u_short *rp, u_char *cp, int len, u_short *crc) 2122 { 2123 u_short td; 2124 u_short mycrc; 2125 2126 /* preload crc for header (4 bytes) 2127 * or data (anything else) 2128 */ 2129 mycrc = (len == 4) ? 0xb230 : 0xe295; 2130 2131 while (len--) { 2132 td = (msencode[*cp >> 4] << 8) | msencode[*cp & 0x0f]; 2133 2134 /* Check for zeros in top bit of encode and bottom 2135 * bit of previous encode. if so, slap a one in betweem 2136 * them. 2137 */ 2138 if ((td & 0x140) == 0) 2139 td |= 0x80; 2140 if ((td & 0x4000) == 0 && (rp[-1] & 1) == 0) 2141 td |= 0x8000; 2142 2143 *rp++ = td; 2144 2145 /* 2146 * calc crc if requested 2147 */ 2148 if (crc) 2149 mycrc = (mycrc << 8) ^ mscrctab[*cp ^ (mycrc >> 8)]; 2150 2151 cp++; 2152 } 2153 2154 if (crc) 2155 *crc = mycrc; 2156 2157 return(rp); 2158 } 2159
Indexes created Thu Oct 02 14:10:14 GMT 2025