fd.c revision 1.66.10.1
1 /* $NetBSD: fd.c,v 1.66.10.1 2006/04/19 02:31:58 elad 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 1.66.10.1 2006/04/19 02:31:58 elad 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/bufq.h> 45 #include <sys/device.h> 46 #include <sys/ioctl.h> 47 #include <sys/fcntl.h> 48 #include <sys/disklabel.h> 49 #include <sys/disk.h> 50 #include <sys/dkbad.h> 51 #include <sys/proc.h> 52 #include <sys/conf.h> 53 54 #include <uvm/uvm_extern.h> 55 56 #include <machine/cpu.h> 57 #include <amiga/amiga/device.h> 58 #include <amiga/amiga/custom.h> 59 #include <amiga/amiga/cia.h> 60 #include <amiga/amiga/cc.h> 61 62 #include "locators.h" 63 64 enum fdc_bits { FDB_CHANGED = 2, FDB_PROTECT, FDB_CYLZERO, FDB_READY }; 65 /* 66 * partitions in fd represent different format floppies 67 * partition a is 0 etc.. 68 */ 69 enum fd_parttypes { 70 FDAMIGAPART = 0, 71 FDMSDOSPART, 72 FDMAXPARTS 73 }; 74 75 #define FDBBSIZE (8192) 76 #define FDSBSIZE (8192) 77 78 #define FDUNIT(dev) DISKUNIT(dev) 79 #define FDPART(dev) DISKPART(dev) 80 #define FDMAKEDEV(m, u, p) MAKEDISKDEV((m), (u), (p)) 81 82 /* that's nice, but we don't want to always use this as an amiga drive 83 bunghole :-) */ 84 #define FDNHEADS (2) /* amiga drives always have 2 heads */ 85 #define FDSECSIZE (512) /* amiga drives always have 512 byte sectors */ 86 #define FDSECLWORDS (128) 87 88 #define FDSETTLEDELAY (18000) /* usec delay after seeking after switch dir */ 89 #define FDSTEPDELAY (3500) /* usec delay after steping */ 90 #define FDPRESIDEDELAY (1000) /* usec delay before writing can occur */ 91 #define FDWRITEDELAY (1300) /* usec delay after write */ 92 93 #define FDSTEPOUT (1) /* decrease track step */ 94 #define FDSTEPIN (0) /* increase track step */ 95 96 #define FDCUNITMASK (0x78) /* mask for all units (bits 6-3) */ 97 98 #define FDRETRIES (2) /* default number of retries */ 99 #define FDMAXUNITS (4) /* maximum number of supported units */ 100 101 #define DISKLEN_READ (0) /* fake mask for reading */ 102 #define DISKLEN_WRITE (1 << 14) /* bit for writing */ 103 #define DISKLEN_DMAEN (1 << 15) /* DMA go */ 104 #define DMABUFSZ ((DISKLEN_WRITE - 1) * 2) /* largest DMA possible */ 105 106 #define FDMFMSYNC (0x4489) 107 #define FDMFMID (0x5554) 108 #define FDMFMDATA (0x5545) 109 #define FDMFMGAP1 (0x9254) 110 #define FDMFMGAP2 (0xAAAA) 111 #define FDMFMGAP3 (0x9254) 112 #define CRC16POLY (0x1021) /* (x^16) + x^12 + x^5 + x^0 */ 113 114 /* 115 * Msdos-type MFM encode/decode 116 */ 117 static u_char msdecode[128]; 118 static u_char msencode[16] = 119 { 120 0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15, 121 0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55 122 }; 123 static u_short mscrctab[256]; 124 125 /* 126 5554 aaaa aaaa aaa5 2aa4 4452 aa51 127 00 00 03 02 ac 0d 128 */ 129 130 /* 131 * floppy device type 132 */ 133 struct fdtype { 134 u_int driveid; /* drive identification (from drive) */ 135 u_int ncylinders; /* number of cylinders on drive */ 136 u_int amiga_nsectors; /* number of sectors per amiga track */ 137 u_int msdos_nsectors; /* number of sectors per msdos track */ 138 u_int nreadw; /* number of words (short) read per track */ 139 u_int nwritew; /* number of words (short) written per track */ 140 u_int gap; /* track gap size in long words */ 141 const u_int precomp[2]; /* 1st and 2nd precomp values */ 142 const char *desc; /* description of drive type (useq) */ 143 }; 144 145 /* 146 * floppy disk device data 147 */ 148 struct fd_softc { 149 struct device sc_dv; /* generic device info; must come first */ 150 struct disk dkdev; /* generic disk info */ 151 struct bufq_state *bufq;/* queue pending I/O operations */ 152 struct buf curbuf; /* state of current I/O operation */ 153 struct callout calibrate_ch; 154 struct callout motor_ch; 155 struct fdtype *type; 156 void *cachep; /* cached track data (write through) */ 157 int cachetrk; /* cahced track -1 for none */ 158 int hwunit; /* unit for amiga controlling hw */ 159 int unitmask; /* mask for cia select deslect */ 160 int pstepdir; /* previous step direction */ 161 int curcyl; /* current curcyl head positioned on */ 162 int flags; /* misc flags */ 163 int wlabel; 164 int stepdelay; /* useq to delay after seek user setable */ 165 int nsectors; /* number of sectors per track */ 166 int openpart; /* which partition [ab] == [12] is open */ 167 short retries; /* number of times to retry failed io */ 168 short retried; /* number of times current io retried */ 169 int bytespersec; /* number of bytes per sector */ 170 }; 171 172 /* fd_softc->flags */ 173 #define FDF_MOTORON (0x01) /* motor is running */ 174 #define FDF_MOTOROFF (0x02) /* motor is waiting to be turned off */ 175 #define FDF_WMOTOROFF (0x04) /* unit wants a wakeup after off */ 176 #define FDF_DIRTY (0x08) /* track cache needs write */ 177 #define FDF_WRITEWAIT (0x10) /* need to head select delay on next setpos */ 178 #define FDF_HAVELABEL (0x20) /* label is valid */ 179 #define FDF_JUSTFLUSH (0x40) /* don't bother caching track. */ 180 #define FDF_NOTRACK0 (0x80) /* was not able to recalibrate drive */ 181 182 int fdc_wantwakeup; 183 int fdc_side; 184 void *fdc_dmap; 185 struct fd_softc *fdc_indma; 186 int fdc_dmalen; 187 int fdc_dmawrite; 188 189 struct fdcargs { 190 struct fdtype *type; 191 int unit; 192 }; 193 194 int fdcmatch(struct device *, struct cfdata *, void *); 195 void fdcattach(struct device *, struct device *, void *); 196 int fdcprint(void *, const char *); 197 int fdmatch(struct device *, struct cfdata *, void *); 198 void fdattach(struct device *, struct device *, void *); 199 200 void fdintr(int); 201 void fdidxintr(void); 202 int fdloaddisk(struct fd_softc *); 203 void fdgetdefaultlabel(struct fd_softc *, struct disklabel *, int); 204 int fdgetdisklabel(struct fd_softc *, dev_t); 205 int fdsetdisklabel(struct fd_softc *, struct disklabel *); 206 int fdputdisklabel(struct fd_softc *, dev_t); 207 struct fdtype * fdcgetfdtype(int); 208 void fdmotoroff(void *); 209 void fdsetpos(struct fd_softc *, int, int); 210 void fdselunit(struct fd_softc *); 211 void fdstart(struct fd_softc *); 212 void fdcont(struct fd_softc *); 213 void fddmastart(struct fd_softc *, int); 214 void fdcalibrate(void *); 215 void fddmadone(struct fd_softc *, int); 216 void fddone(struct fd_softc *); 217 void fdfindwork(int); 218 void fdminphys(struct buf *); 219 void fdcachetoraw(struct fd_softc *); 220 void amcachetoraw(struct fd_softc *); 221 int amrawtocache(struct fd_softc *); 222 u_long *fdfindsync(u_long *, u_long *); 223 int fdrawtocache(struct fd_softc *); 224 void mscachetoraw(struct fd_softc *); 225 int msrawtocache(struct fd_softc *); 226 u_long *mfmblkencode(u_long *, u_long *, u_long *, int); 227 u_long *mfmblkdecode(u_long *, u_long *, u_long *, int); 228 u_short *msblkdecode(u_short *, u_char *, int); 229 u_short *msblkencode(u_short *, u_char *, int, u_short *); 230 231 /* 232 * read size is (nsectors + 1) * mfm secsize + gap bytes + 2 shorts 233 * write size is nsectors * mfm secsize + gap bytes + 3 shorts 234 * the extra shorts are to deal with a DMA hw bug in the controller 235 * they are probably too much (I belive the bug is 1 short on write and 236 * 3 bits on read) but there is no need to be cheap here. 237 */ 238 #define MAXTRKSZ (22 * FDSECSIZE) 239 struct fdtype fdtype[] = { 240 { 0x00000000, 80, 11, 9, 7358, 6815, 414, { 80, 161 }, "3.5dd" }, 241 { 0x55555555, 40, 11, 9, 7358, 6815, 414, { 80, 161 }, "5.25dd" }, 242 { 0xAAAAAAAA, 80, 22, 18, 14716, 13630, 828, { 80, 161 }, "3.5hd" } 243 }; 244 int nfdtype = sizeof(fdtype) / sizeof(*fdtype); 245 246 CFATTACH_DECL(fd, sizeof(struct fd_softc), 247 fdmatch, fdattach, NULL, NULL); 248 249 extern struct cfdriver fd_cd; 250 251 dev_type_open(fdopen); 252 dev_type_close(fdclose); 253 dev_type_read(fdread); 254 dev_type_write(fdwrite); 255 dev_type_ioctl(fdioctl); 256 dev_type_strategy(fdstrategy); 257 258 const struct bdevsw fd_bdevsw = { 259 fdopen, fdclose, fdstrategy, fdioctl, nodump, nosize, D_DISK 260 }; 261 262 const struct cdevsw fd_cdevsw = { 263 fdopen, fdclose, fdread, fdwrite, fdioctl, 264 nostop, notty, nopoll, nommap, nokqfilter, D_DISK 265 }; 266 267 struct dkdriver fddkdriver = { fdstrategy }; 268 269 CFATTACH_DECL(fdc, sizeof(struct device), 270 fdcmatch, fdcattach, NULL, NULL); 271 272 /* 273 * all hw access through macros, this helps to hide the active low 274 * properties 275 */ 276 277 #define FDUNITMASK(unit) (1 << (3 + (unit))) 278 279 /* 280 * select units using mask 281 */ 282 #define FDSELECT(um) do { ciab.prb &= ~(um); } while (0) 283 284 /* 285 * deselect units using mask 286 */ 287 #define FDDESELECT(um) do { ciab.prb |= (um); delay(1); } while (0) 288 289 /* 290 * test hw condition bits 291 */ 292 #define FDTESTC(bit) ((ciaa.pra & (1 << (bit))) == 0) 293 294 /* 295 * set motor for select units, true motor on else off 296 */ 297 #define FDSETMOTOR(on) do { \ 298 if (on) ciab.prb &= ~CIAB_PRB_MTR; else ciab.prb |= CIAB_PRB_MTR; \ 299 } while (0) 300 301 /* 302 * set head for select units 303 */ 304 #define FDSETHEAD(head) do { \ 305 if (head) ciab.prb &= ~CIAB_PRB_SIDE; else ciab.prb |= CIAB_PRB_SIDE; \ 306 delay(1); } while (0) 307 308 /* 309 * select direction, true towards spindle else outwards 310 */ 311 #define FDSETDIR(in) do { \ 312 if (in) ciab.prb &= ~CIAB_PRB_DIR; else ciab.prb |= CIAB_PRB_DIR; \ 313 delay(1); } while (0) 314 315 /* 316 * step the selected units 317 */ 318 #define FDSTEP do { \ 319 ciab.prb &= ~CIAB_PRB_STEP; ciab.prb |= CIAB_PRB_STEP; \ 320 } while (0) 321 322 #define FDDMASTART(len, towrite) do { \ 323 int dmasz = (len) | ((towrite) ? DISKLEN_WRITE : 0) | DISKLEN_DMAEN; \ 324 custom.dsklen = dmasz; custom.dsklen = dmasz; } while (0) 325 326 #define FDDMASTOP do { custom.dsklen = 0; } while (0) 327 328 329 int 330 fdcmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 331 { 332 static int fdc_matched = 0; 333 334 /* Allow only once instance. */ 335 if (matchname("fdc", auxp) == 0 || fdc_matched) 336 return(0); 337 if ((fdc_dmap = alloc_chipmem(DMABUFSZ)) == NULL) { 338 printf("fdc: unable to allocate DMA buffer\n"); 339 return(0); 340 } 341 342 fdc_matched = 1; 343 return(1); 344 } 345 346 void 347 fdcattach(struct device *pdp, struct device *dp, void *auxp) 348 { 349 struct fdcargs args; 350 351 printf(": dmabuf pa 0x%x", kvtop(fdc_dmap)); 352 printf(": dmabuf ka %p\n", fdc_dmap); 353 args.unit = 0; 354 args.type = fdcgetfdtype(args.unit); 355 356 fdc_side = -1; 357 config_found(dp, &args, fdcprint); 358 for (args.unit++; args.unit < FDMAXUNITS; args.unit++) { 359 if ((args.type = fdcgetfdtype(args.unit)) == NULL) 360 continue; 361 config_found(dp, &args, fdcprint); 362 } 363 } 364 365 int 366 fdcprint(void *auxp, const char *pnp) 367 { 368 struct fdcargs *fcp; 369 370 fcp = auxp; 371 if (pnp) 372 aprint_normal("fd%d at %s unit %d:", fcp->unit, pnp, 373 fcp->type->driveid); 374 return(UNCONF); 375 } 376 377 /*ARGSUSED*/ 378 int 379 fdmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 380 { 381 struct fdcargs *fdap; 382 383 fdap = auxp; 384 if (cfp->cf_loc[FDCCF_UNIT] == fdap->unit || 385 cfp->cf_loc[FDCCF_UNIT] == FDCCF_UNIT_DEFAULT) 386 return(1); 387 388 return(0); 389 } 390 391 void 392 fdattach(struct device *pdp, struct device *dp, void *auxp) 393 { 394 struct fdcargs *ap; 395 struct fd_softc *sc; 396 int i; 397 398 ap = auxp; 399 sc = (struct fd_softc *)dp; 400 401 bufq_alloc(&sc->bufq, "disksort", BUFQ_SORT_CYLINDER); 402 callout_init(&sc->calibrate_ch); 403 callout_init(&sc->motor_ch); 404 405 sc->curcyl = sc->cachetrk = -1; 406 sc->openpart = -1; 407 sc->type = ap->type; 408 sc->hwunit = ap->unit; 409 sc->unitmask = 1 << (3 + ap->unit); 410 sc->retries = FDRETRIES; 411 sc->stepdelay = FDSTEPDELAY; 412 sc->bytespersec = 512; 413 printf(" unit %d: %s %d cyl, %d head, %d sec [%d sec], 512 bytes/sec\n", 414 sc->hwunit, sc->type->desc, sc->type->ncylinders, FDNHEADS, 415 sc->type->amiga_nsectors, sc->type->msdos_nsectors); 416 417 /* 418 * Initialize and attach the disk structure. 419 */ 420 sc->dkdev.dk_name = sc->sc_dv.dv_xname; 421 sc->dkdev.dk_driver = &fddkdriver; 422 disk_attach(&sc->dkdev); 423 424 /* 425 * calibrate the drive 426 */ 427 fdsetpos(sc, 0, 0); 428 fdsetpos(sc, sc->type->ncylinders, 0); 429 fdsetpos(sc, 0, 0); 430 fdmotoroff(sc); 431 432 /* 433 * precalc msdos MFM and CRC 434 */ 435 for (i = 0; i < 128; i++) 436 msdecode[i] = 0xff; 437 for (i = 0; i < 16; i++) 438 msdecode[msencode[i]] = i; 439 for (i = 0; i < 256; i++) { 440 mscrctab[i] = (0x1021 * (i & 0xf0)) ^ (0x1021 * (i & 0x0f)) ^ 441 (0x1021 * (i >> 4)); 442 } 443 444 /* 445 * enable disk related interrupts 446 */ 447 custom.dmacon = DMAF_SETCLR | DMAF_MASTER | DMAF_DISK; 448 custom.intena = INTF_SETCLR | INTF_DSKBLK; 449 ciab.icr = CIA_ICR_FLG; 450 } 451 452 /*ARGSUSED*/ 453 int 454 fdopen(dev_t dev, int flags, int devtype, struct lwp *l) 455 { 456 struct fd_softc *sc; 457 int wasopen, fwork, error, s; 458 459 error = 0; 460 461 if (FDPART(dev) >= FDMAXPARTS) 462 return(ENXIO); 463 464 if ((sc = getsoftc(fd_cd, FDUNIT(dev))) == NULL) 465 return(ENXIO); 466 if (sc->flags & FDF_NOTRACK0) 467 return(ENXIO); 468 if (sc->cachep == NULL) 469 sc->cachep = malloc(MAXTRKSZ, M_DEVBUF, M_WAITOK); 470 471 s = splbio(); 472 /* 473 * if we are sleeping in fdclose(); waiting for a chance to 474 * shut the motor off, do a sleep here also. 475 */ 476 while (sc->flags & FDF_WMOTOROFF) 477 tsleep(fdmotoroff, PRIBIO, "fdopen", 0); 478 479 fwork = 0; 480 /* 481 * if not open let user open request type, otherwise 482 * ensure they are trying to open same type. 483 */ 484 if (sc->openpart == FDPART(dev)) 485 wasopen = 1; 486 else if (sc->openpart == -1) { 487 sc->openpart = FDPART(dev); 488 wasopen = 0; 489 } else { 490 wasopen = 1; 491 error = EPERM; 492 goto done; 493 } 494 495 /* 496 * wait for current io to complete if any 497 */ 498 if (fdc_indma) { 499 fwork = 1; 500 fdc_wantwakeup++; 501 tsleep(fdopen, PRIBIO, "fdopen", 0); 502 } 503 if ((error = fdloaddisk(sc)) != 0) 504 goto done; 505 if ((error = fdgetdisklabel(sc, dev)) != 0) 506 goto done; 507 #ifdef FDDEBUG 508 printf(" open successful\n"); 509 #endif 510 done: 511 /* 512 * if we requested that fddone()->fdfindwork() wake us, allow it to 513 * complete its job now 514 */ 515 if (fwork) 516 fdfindwork(FDUNIT(dev)); 517 splx(s); 518 519 /* 520 * if we were not open and we marked us so reverse that. 521 */ 522 if (error && wasopen == 0) 523 sc->openpart = -1; 524 return(error); 525 } 526 527 /*ARGSUSED*/ 528 int 529 fdclose(dev_t dev, int flags, int devtype, struct lwp *l) 530 { 531 struct fd_softc *sc; 532 int s; 533 534 #ifdef FDDEBUG 535 printf("fdclose()\n"); 536 #endif 537 sc = getsoftc(fd_cd, FDUNIT(dev)); 538 s = splbio(); 539 if (sc->flags & FDF_MOTORON) { 540 sc->flags |= FDF_WMOTOROFF; 541 tsleep(fdmotoroff, PRIBIO, "fdclose", 0); 542 sc->flags &= ~FDF_WMOTOROFF; 543 wakeup(fdmotoroff); 544 } 545 sc->openpart = -1; 546 splx(s); 547 return(0); 548 } 549 550 int 551 fdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct lwp *l) 552 { 553 struct fd_softc *sc; 554 int error, wlab; 555 556 sc = getsoftc(fd_cd, FDUNIT(dev)); 557 558 if ((sc->flags & FDF_HAVELABEL) == 0) 559 return(EBADF); 560 561 switch (cmd) { 562 case DIOCSBAD: 563 return(EINVAL); 564 case DIOCSRETRIES: 565 if (*(int *)addr < 0) 566 return(EINVAL); 567 sc->retries = *(int *)addr; 568 return(0); 569 case DIOCSSTEP: 570 if (*(int *)addr < FDSTEPDELAY) 571 return(EINVAL); 572 sc->dkdev.dk_label->d_trkseek = sc->stepdelay = *(int *)addr; 573 return(0); 574 case DIOCGDINFO: 575 *(struct disklabel *)addr = *(sc->dkdev.dk_label); 576 return(0); 577 case DIOCGPART: 578 ((struct partinfo *)addr)->disklab = sc->dkdev.dk_label; 579 ((struct partinfo *)addr)->part = 580 &sc->dkdev.dk_label->d_partitions[FDPART(dev)]; 581 return(0); 582 case DIOCSDINFO: 583 if ((flag & FWRITE) == 0) 584 return(EBADF); 585 return(fdsetdisklabel(sc, (struct disklabel *)addr)); 586 case DIOCWDINFO: 587 if ((flag & FWRITE) == 0) 588 return(EBADF); 589 if ((error = fdsetdisklabel(sc, (struct disklabel *)addr)) != 0) 590 return(error); 591 wlab = sc->wlabel; 592 sc->wlabel = 1; 593 error = fdputdisklabel(sc, dev); 594 sc->wlabel = wlab; 595 return(error); 596 case DIOCWLABEL: 597 if ((flag & FWRITE) == 0) 598 return(EBADF); 599 sc->wlabel = *(int *)addr; 600 return(0); 601 case DIOCGDEFLABEL: 602 fdgetdefaultlabel(sc, (struct disklabel *)addr, FDPART(dev)); 603 return(0); 604 default: 605 return(ENOTTY); 606 } 607 } 608 609 int 610 fdread(dev_t dev, struct uio *uio, int flags) 611 { 612 return (physio(fdstrategy, NULL, dev, B_READ, fdminphys, uio)); 613 } 614 615 int 616 fdwrite(dev_t dev, struct uio *uio, int flags) 617 { 618 return (physio(fdstrategy, NULL, dev, B_WRITE, fdminphys, uio)); 619 } 620 621 622 void 623 fdintr(int flag) 624 { 625 int s; 626 627 s = splbio(); 628 if (fdc_indma) 629 fddmadone(fdc_indma, 0); 630 splx(s); 631 } 632 633 void 634 fdidxintr(void) 635 { 636 if (fdc_indma && fdc_dmalen) { 637 /* 638 * turn off intr and start actual dma 639 */ 640 ciab.icr = CIA_ICR_FLG; 641 FDDMASTART(fdc_dmalen, fdc_dmawrite); 642 fdc_dmalen = 0; 643 } 644 } 645 646 void 647 fdstrategy(struct buf *bp) 648 { 649 struct disklabel *lp; 650 struct fd_softc *sc; 651 int unit, part, s; 652 653 unit = FDUNIT(bp->b_dev); 654 part = FDPART(bp->b_dev); 655 sc = getsoftc(fd_cd, unit); 656 657 #ifdef FDDEBUG 658 printf("fdstrategy: %p\n", bp); 659 #endif 660 /* 661 * check for valid partition and bounds 662 */ 663 lp = sc->dkdev.dk_label; 664 if ((sc->flags & FDF_HAVELABEL) == 0) { 665 bp->b_error = EIO; 666 goto bad; 667 } 668 if (bounds_check_with_label(&sc->dkdev, bp, sc->wlabel) <= 0) 669 goto done; 670 671 /* 672 * trans count of zero or bounds check indicates io is done 673 * we are done. 674 */ 675 if (bp->b_bcount == 0) 676 goto done; 677 678 bp->b_rawblkno = bp->b_blkno; 679 680 /* 681 * queue the buf and kick the low level code 682 */ 683 s = splbio(); 684 BUFQ_PUT(sc->bufq, bp); 685 fdstart(sc); 686 splx(s); 687 return; 688 bad: 689 bp->b_flags |= B_ERROR; 690 done: 691 bp->b_resid = bp->b_bcount; 692 biodone(bp); 693 } 694 695 /* 696 * make sure disk is loaded and label is up-to-date. 697 */ 698 int 699 fdloaddisk(struct fd_softc *sc) 700 { 701 /* 702 * if diskchange is low step drive to 0 then up one then to zero. 703 */ 704 fdselunit(sc); /* make sure the unit is selected */ 705 if (FDTESTC(FDB_CHANGED)) { 706 fdsetpos(sc, 0, 0); 707 sc->cachetrk = -1; /* invalidate the cache */ 708 sc->flags &= ~FDF_HAVELABEL; 709 fdsetpos(sc, FDNHEADS, 0); 710 fdsetpos(sc, 0, 0); 711 if (FDTESTC(FDB_CHANGED)) { 712 fdmotoroff(sc); 713 FDDESELECT(sc->unitmask); 714 return(ENXIO); 715 } 716 } 717 FDDESELECT(sc->unitmask); 718 fdmotoroff(sc); 719 sc->type = fdcgetfdtype(sc->hwunit); 720 if (sc->type == NULL) 721 return(ENXIO); 722 if (sc->openpart == FDMSDOSPART) 723 sc->nsectors = sc->type->msdos_nsectors; 724 else 725 sc->nsectors = sc->type->amiga_nsectors; 726 return(0); 727 } 728 729 void 730 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 731 /* (variable part) XXX ick */ 732 { 733 734 bzero(lp, sizeof(struct disklabel)); 735 lp->d_secsize = FDSECSIZE; 736 lp->d_ntracks = FDNHEADS; 737 lp->d_ncylinders = sc->type->ncylinders; 738 lp->d_nsectors = sc->nsectors; 739 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 740 lp->d_type = DTYPE_FLOPPY; 741 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 742 lp->d_rpm = 300; /* good guess I suppose. */ 743 lp->d_interleave = 1; /* should change when adding msdos */ 744 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 745 lp->d_bbsize = 0; 746 lp->d_sbsize = 0; 747 lp->d_partitions[part].p_size = lp->d_secperunit; 748 lp->d_partitions[part].p_fstype = FS_UNUSED; 749 lp->d_partitions[part].p_fsize = 1024; 750 lp->d_partitions[part].p_frag = 8; 751 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 752 lp->d_npartitions = part + 1; 753 lp->d_magic = lp->d_magic2 = DISKMAGIC; 754 lp->d_checksum = dkcksum(lp); 755 } 756 757 /* 758 * read disk label, if present otherwise create one 759 * return a new label if raw part and none found, otherwise err. 760 */ 761 int 762 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 763 { 764 struct disklabel *lp, *dlp; 765 struct cpu_disklabel *clp; 766 struct buf *bp; 767 int error, part; 768 769 if (sc->flags & FDF_HAVELABEL && 770 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 771 return(0); 772 #ifdef FDDEBUG 773 printf("fdgetdisklabel()\n"); 774 #endif 775 part = FDPART(dev); 776 lp = sc->dkdev.dk_label; 777 clp = sc->dkdev.dk_cpulabel; 778 bzero(lp, sizeof(struct disklabel)); 779 bzero(clp, sizeof(struct cpu_disklabel)); 780 781 lp->d_secsize = FDSECSIZE; 782 lp->d_ntracks = FDNHEADS; 783 lp->d_ncylinders = sc->type->ncylinders; 784 lp->d_nsectors = sc->nsectors; 785 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 786 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 787 lp->d_npartitions = part + 1; 788 lp->d_partitions[part].p_size = lp->d_secperunit; 789 lp->d_partitions[part].p_fstype = FS_UNUSED; 790 lp->d_partitions[part].p_fsize = 1024; 791 lp->d_partitions[part].p_frag = 8; 792 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 793 794 sc->flags |= FDF_HAVELABEL; 795 796 bp = (void *)geteblk((int)lp->d_secsize); 797 bp->b_dev = dev; 798 bp->b_blkno = 0; 799 bp->b_cylinder = 0; 800 bp->b_bcount = FDSECSIZE; 801 bp->b_flags |= B_READ; 802 fdstrategy(bp); 803 if ((error = biowait(bp)) != 0) 804 goto nolabel; 805 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 806 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 807 dkcksum(dlp)) { 808 error = EINVAL; 809 goto nolabel; 810 } 811 bcopy(dlp, lp, sizeof(struct disklabel)); 812 if (lp->d_trkseek > FDSTEPDELAY) 813 sc->stepdelay = lp->d_trkseek; 814 brelse(bp); 815 return(0); 816 nolabel: 817 fdgetdefaultlabel(sc, lp, part); 818 brelse(bp); 819 return(0); 820 } 821 822 /* 823 * set the incore copy of this units disklabel 824 */ 825 int 826 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 827 { 828 struct disklabel *clp; 829 struct partition *pp; 830 831 /* 832 * must have at least opened raw unit to fetch the 833 * raw_part stuff. 834 */ 835 if ((sc->flags & FDF_HAVELABEL) == 0) 836 return(EINVAL); 837 clp = sc->dkdev.dk_label; 838 /* 839 * make sure things check out and we only have one valid 840 * partition 841 */ 842 #ifdef FDDEBUG 843 printf("fdsetdisklabel\n"); 844 #endif 845 if (lp->d_secsize != FDSECSIZE || 846 lp->d_nsectors != clp->d_nsectors || 847 lp->d_ntracks != FDNHEADS || 848 lp->d_ncylinders != clp->d_ncylinders || 849 lp->d_secpercyl != clp->d_secpercyl || 850 lp->d_secperunit != clp->d_secperunit || 851 lp->d_magic != DISKMAGIC || 852 lp->d_magic2 != DISKMAGIC || 853 lp->d_npartitions == 0 || 854 lp->d_npartitions > FDMAXPARTS || 855 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 856 dkcksum(lp)) 857 return(EINVAL); 858 /* 859 * if any partitions are present make sure they 860 * represent the currently open type 861 */ 862 if ((pp = &lp->d_partitions[0])->p_size) { 863 if ((pp = &lp->d_partitions[1])->p_size == 0) 864 goto done; 865 else if (sc->openpart != 1) 866 return(EINVAL); 867 } else if (sc->openpart != 0) 868 return(EINVAL); 869 /* 870 * make sure selected partition is within bounds 871 * XXX on the second check, its to handle a bug in 872 * XXX the cluster routines as they require mutliples 873 * XXX of PAGE_SIZE currently 874 */ 875 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 876 (pp->p_frag * pp->p_fsize % PAGE_SIZE)) 877 return(EINVAL); 878 done: 879 bcopy(lp, clp, sizeof(struct disklabel)); 880 return(0); 881 } 882 883 /* 884 * write out the incore copy of this units disklabel 885 */ 886 int 887 fdputdisklabel(struct fd_softc *sc, dev_t dev) 888 { 889 struct disklabel *lp, *dlp; 890 struct buf *bp; 891 int error; 892 893 if ((sc->flags & FDF_HAVELABEL) == 0) 894 return(EBADF); 895 #ifdef FDDEBUG 896 printf("fdputdisklabel\n"); 897 #endif 898 /* 899 * get buf and read in sector 0 900 */ 901 lp = sc->dkdev.dk_label; 902 bp = geteblk((int)lp->d_secsize); 903 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 904 bp->b_blkno = 0; 905 bp->b_cylinder = 0; 906 bp->b_bcount = FDSECSIZE; 907 bp->b_flags |= B_READ; 908 fdstrategy(bp); 909 if ((error = biowait(bp)) != 0) 910 goto done; 911 /* 912 * copy disklabel to buf and write it out synchronous 913 */ 914 dlp = (struct disklabel *)(bp->b_data + LABELOFFSET); 915 bcopy(lp, dlp, sizeof(struct disklabel)); 916 bp->b_blkno = 0; 917 bp->b_cylinder = 0; 918 bp->b_flags &= ~(B_READ|B_DONE); 919 bp->b_flags |= B_WRITE; 920 fdstrategy(bp); 921 error = biowait(bp); 922 done: 923 brelse(bp); 924 return(error); 925 } 926 927 /* 928 * figure out drive type or NULL if none. 929 */ 930 struct fdtype * 931 fdcgetfdtype(int unit) 932 { 933 struct fdtype *ftp; 934 u_long id, idb; 935 int cnt, umask; 936 937 id = 0; 938 umask = 1 << (3 + unit); 939 940 FDDESELECT(FDCUNITMASK); 941 942 FDSETMOTOR(1); 943 delay(1); 944 FDSELECT(umask); 945 delay(1); 946 FDDESELECT(umask); 947 948 FDSETMOTOR(0); 949 delay(1); 950 FDSELECT(umask); 951 delay(1); 952 FDDESELECT(umask); 953 954 for (idb = 0x80000000; idb; idb >>= 1) { 955 FDSELECT(umask); 956 delay(1); 957 if (FDTESTC(FDB_READY) == 0) 958 id |= idb; 959 FDDESELECT(umask); 960 delay(1); 961 } 962 #ifdef FDDEBUG 963 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 964 #endif 965 966 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 967 if (ftp->driveid == id) 968 return(ftp); 969 /* 970 * 3.5dd's at unit 0 do not always return id. 971 */ 972 if (unit == 0) 973 return(fdtype); 974 return(NULL); 975 } 976 977 /* 978 * turn motor off if possible otherwise mark as needed and will be done 979 * later. 980 */ 981 void 982 fdmotoroff(void *arg) 983 { 984 struct fd_softc *sc; 985 int s; 986 987 sc = arg; 988 s = splbio(); 989 990 #ifdef FDDEBUG 991 printf("fdmotoroff: unit %d\n", sc->hwunit); 992 #endif 993 if ((sc->flags & FDF_MOTORON) == 0) 994 goto done; 995 /* 996 * if we have a timeout on a DMA operation let fddmadone() 997 * deal with it. 998 */ 999 if (fdc_indma == sc) { 1000 fddmadone(sc, 1); 1001 goto done; 1002 } 1003 #ifdef FDDEBUG 1004 printf(" motor was on, turning off\n"); 1005 #endif 1006 1007 /* 1008 * flush cache if needed 1009 */ 1010 if (sc->flags & FDF_DIRTY) { 1011 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1012 #ifdef FDDEBUG 1013 printf(" flushing dirty buffer first\n"); 1014 #endif 1015 /* 1016 * if DMA'ing done for now, fddone() will call us again 1017 */ 1018 if (fdc_indma) 1019 goto done; 1020 fddmastart(sc, sc->cachetrk); 1021 goto done; 1022 } 1023 1024 /* 1025 * if controller is busy just schedule us to be called back 1026 */ 1027 if (fdc_indma) { 1028 /* 1029 * someone else has the controller now 1030 * just set flag and let fddone() call us again. 1031 */ 1032 sc->flags |= FDF_MOTOROFF; 1033 goto done; 1034 } 1035 1036 #ifdef FDDEBUG 1037 printf(" hw turning unit off\n"); 1038 #endif 1039 1040 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1041 FDDESELECT(FDCUNITMASK); 1042 FDSETMOTOR(0); 1043 delay(1); 1044 FDSELECT(sc->unitmask); 1045 delay(4); 1046 FDDESELECT(sc->unitmask); 1047 delay(1); 1048 if (sc->flags & FDF_WMOTOROFF) 1049 wakeup(fdmotoroff); 1050 done: 1051 splx(s); 1052 } 1053 1054 /* 1055 * select drive seek to track exit with motor on. 1056 * fdsetpos(x, 0, 0) does calibrates the drive. 1057 */ 1058 void 1059 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1060 { 1061 int nstep, sdir, ondly, ncyl, nside; 1062 1063 FDDESELECT(FDCUNITMASK); 1064 FDSETMOTOR(1); 1065 delay(1); 1066 FDSELECT(sc->unitmask); 1067 delay(1); 1068 if ((sc->flags & FDF_MOTORON) == 0) { 1069 ondly = 0; 1070 while (FDTESTC(FDB_READY) == 0) { 1071 delay(1000); 1072 if (++ondly >= 1000) 1073 break; 1074 } 1075 } 1076 sc->flags |= FDF_MOTORON; 1077 1078 ncyl = trk / FDNHEADS; 1079 nside = trk % FDNHEADS; 1080 1081 if (sc->curcyl == ncyl && fdc_side == nside) 1082 return; 1083 1084 if (towrite) 1085 sc->flags |= FDF_WRITEWAIT; 1086 1087 #ifdef FDDEBUG 1088 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1089 trk % FDNHEADS, towrite); 1090 #endif 1091 nstep = ncyl - sc->curcyl; 1092 if (nstep) { 1093 /* 1094 * figure direction 1095 */ 1096 if (nstep > 0 && ncyl != 0) { 1097 sdir = FDSTEPIN; 1098 FDSETDIR(1); 1099 } else { 1100 nstep = -nstep; 1101 sdir = FDSTEPOUT; 1102 FDSETDIR(0); 1103 } 1104 if (ncyl == 0) { 1105 /* 1106 * either just want cylinder 0 or doing 1107 * a calibrate. 1108 */ 1109 nstep = 256; 1110 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1111 FDSTEP; 1112 delay(sc->stepdelay); 1113 } 1114 if (nstep < 0) 1115 sc->flags |= FDF_NOTRACK0; 1116 } else { 1117 /* 1118 * step the needed amount amount. 1119 */ 1120 while (nstep--) { 1121 FDSTEP; 1122 delay(sc->stepdelay); 1123 } 1124 } 1125 /* 1126 * if switched directions 1127 * allow drive to settle. 1128 */ 1129 if (sc->pstepdir != sdir) 1130 delay(FDSETTLEDELAY); 1131 sc->pstepdir = sdir; 1132 sc->curcyl = ncyl; 1133 } 1134 if (nside == fdc_side) 1135 return; 1136 /* 1137 * select side 1138 */ 1139 fdc_side = nside; 1140 FDSETHEAD(nside); 1141 delay(FDPRESIDEDELAY); 1142 } 1143 1144 void 1145 fdselunit(struct fd_softc *sc) 1146 { 1147 FDDESELECT(FDCUNITMASK); /* deselect all */ 1148 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1149 delay(1); 1150 FDSELECT(sc->unitmask); /* select unit */ 1151 delay(1); 1152 } 1153 1154 /* 1155 * process next buf on device queue. 1156 * normall sequence of events: 1157 * fdstart() -> fddmastart(); 1158 * fdidxintr(); 1159 * fdintr() -> fddmadone() -> fddone(); 1160 * if the track is in the cache then fdstart() will short-circuit 1161 * to fddone() else if the track cache is dirty it will flush. If 1162 * the buf is not an entire track it will cache the requested track. 1163 */ 1164 void 1165 fdstart(struct fd_softc *sc) 1166 { 1167 int trk, error, write; 1168 struct buf *bp, *dp; 1169 int changed; 1170 1171 #ifdef FDDEBUG 1172 printf("fdstart: unit %d\n", sc->hwunit); 1173 #endif 1174 1175 /* 1176 * if DMA'ing just return. we must have been called from fdstartegy. 1177 */ 1178 if (fdc_indma) 1179 return; 1180 1181 /* 1182 * get next buf if there. 1183 */ 1184 dp = &sc->curbuf; 1185 if ((bp = BUFQ_PEEK(sc->bufq)) == NULL) { 1186 #ifdef FDDEBUG 1187 printf(" nothing to do\n"); 1188 #endif 1189 return; 1190 } 1191 1192 /* 1193 * Mark us as busy now, in case fddone() gets called in one 1194 * of the cases below. 1195 */ 1196 disk_busy(&sc->dkdev); 1197 1198 /* 1199 * make sure same disk is loaded 1200 */ 1201 fdselunit(sc); 1202 changed = FDTESTC(FDB_CHANGED); 1203 FDDESELECT(sc->unitmask); 1204 if (changed) { 1205 /* 1206 * disk missing, invalidate all future io on 1207 * this unit until re-open()'ed also invalidate 1208 * all current io 1209 */ 1210 printf("fdstart: disk changed\n"); 1211 #ifdef FDDEBUG 1212 printf(" disk was removed invalidating all io\n"); 1213 #endif 1214 sc->flags &= ~FDF_HAVELABEL; 1215 for (;;) { 1216 bp = BUFQ_GET(sc->bufq); 1217 bp->b_flags |= B_ERROR; 1218 bp->b_error = EIO; 1219 if (BUFQ_PEEK(sc->bufq) == NULL) 1220 break; 1221 biodone(bp); 1222 } 1223 /* 1224 * do fddone() on last buf to allow other units to start. 1225 */ 1226 BUFQ_PUT(sc->bufq, bp); 1227 fddone(sc); 1228 return; 1229 } 1230 1231 /* 1232 * we have a valid buf, setup our local version 1233 * we use this count to allow reading over multiple tracks. 1234 * into a single buffer 1235 */ 1236 dp->b_bcount = bp->b_bcount; 1237 dp->b_blkno = bp->b_blkno; 1238 dp->b_data = bp->b_data; 1239 dp->b_flags = bp->b_flags; 1240 dp->b_resid = 0; 1241 1242 if (bp->b_flags & B_READ) 1243 write = 0; 1244 else if (FDTESTC(FDB_PROTECT) == 0) 1245 write = 1; 1246 else { 1247 error = EPERM; 1248 goto bad; 1249 } 1250 1251 /* 1252 * figure trk given blkno 1253 */ 1254 trk = bp->b_blkno / sc->nsectors; 1255 1256 /* 1257 * check to see if same as currently cached track 1258 * if so we need to do no DMA read. 1259 */ 1260 if (trk == sc->cachetrk) { 1261 fddone(sc); 1262 return; 1263 } 1264 1265 /* 1266 * if we will be overwriting the entire cache, don't bother to 1267 * fetch it. 1268 */ 1269 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1270 bp->b_blkno % sc->nsectors == 0) { 1271 if (sc->flags & FDF_DIRTY) 1272 sc->flags |= FDF_JUSTFLUSH; 1273 else { 1274 sc->cachetrk = trk; 1275 fddone(sc); 1276 return; 1277 } 1278 } 1279 1280 /* 1281 * start DMA read of `trk' 1282 */ 1283 fddmastart(sc, trk); 1284 return; 1285 bad: 1286 bp->b_flags |= B_ERROR; 1287 bp->b_error = error; 1288 fddone(sc); 1289 } 1290 1291 /* 1292 * continue a started operation on next track. always begin at 1293 * sector 0 on the next track. 1294 */ 1295 void 1296 fdcont(struct fd_softc *sc) 1297 { 1298 struct buf *dp, *bp; 1299 int trk, write; 1300 1301 dp = &sc->curbuf; 1302 bp = BUFQ_PEEK(sc->bufq); 1303 dp->b_data += (dp->b_bcount - bp->b_resid); 1304 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1305 dp->b_bcount = bp->b_resid; 1306 1307 /* 1308 * figure trk given blkno 1309 */ 1310 trk = dp->b_blkno / sc->nsectors; 1311 #ifdef DEBUG 1312 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1313 panic("fdcont: confused"); 1314 #endif 1315 if (dp->b_flags & B_READ) 1316 write = 0; 1317 else 1318 write = 1; 1319 /* 1320 * if we will be overwriting the entire cache, don't bother to 1321 * fetch it. 1322 */ 1323 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1324 if (sc->flags & FDF_DIRTY) 1325 sc->flags |= FDF_JUSTFLUSH; 1326 else { 1327 sc->cachetrk = trk; 1328 fddone(sc); 1329 return; 1330 } 1331 } 1332 /* 1333 * start DMA read of `trk' 1334 */ 1335 fddmastart(sc, trk); 1336 return; 1337 } 1338 1339 void 1340 fddmastart(struct fd_softc *sc, int trk) 1341 { 1342 int adkmask, ndmaw, write, dmatrk; 1343 1344 #ifdef FDDEBUG 1345 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1346 trk / FDNHEADS, trk % FDNHEADS); 1347 #endif 1348 /* 1349 * flush the cached track if dirty else read requested track. 1350 */ 1351 if (sc->flags & FDF_DIRTY) { 1352 fdcachetoraw(sc); 1353 ndmaw = sc->type->nwritew; 1354 dmatrk = sc->cachetrk; 1355 write = 1; 1356 } else { 1357 ndmaw = sc->type->nreadw; 1358 dmatrk = trk; 1359 write = 0; 1360 } 1361 1362 #ifdef FDDEBUG 1363 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1364 #endif 1365 sc->cachetrk = trk; 1366 fdc_indma = sc; 1367 fdsetpos(sc, dmatrk, write); 1368 1369 /* 1370 * setup dma stuff 1371 */ 1372 if (write == 0) { 1373 custom.adkcon = ADKF_MSBSYNC; 1374 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1375 custom.dsksync = FDMFMSYNC; 1376 } else { 1377 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1378 ADKF_MSBSYNC; 1379 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1380 if (dmatrk >= sc->type->precomp[0]) 1381 adkmask |= ADKF_PRECOMP0; 1382 if (dmatrk >= sc->type->precomp[1]) 1383 adkmask |= ADKF_PRECOMP1; 1384 custom.adkcon = adkmask; 1385 } 1386 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1387 1388 /* 1389 * If writing an MSDOS track, activate disk index pulse 1390 * interrupt, DMA will be started in the intr routine fdidxintr() 1391 * Otherwise, start the DMA here. 1392 */ 1393 if (write && sc->openpart == FDMSDOSPART) { 1394 fdc_dmalen = ndmaw; 1395 fdc_dmawrite = write; 1396 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1397 } else { 1398 FDDMASTART(ndmaw, write); 1399 fdc_dmalen = 0; 1400 } 1401 1402 #ifdef FDDEBUG 1403 printf(" DMA started\n"); 1404 #endif 1405 } 1406 1407 /* 1408 * recalibrate the drive 1409 */ 1410 void 1411 fdcalibrate(void *arg) 1412 { 1413 struct fd_softc *sc; 1414 static int loopcnt; 1415 1416 sc = arg; 1417 1418 if (loopcnt == 0) { 1419 /* 1420 * seek cyl 0 1421 */ 1422 fdc_indma = sc; 1423 sc->stepdelay += 900; 1424 if (sc->cachetrk > 1) 1425 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1426 sc->stepdelay -= 900; 1427 } 1428 if (loopcnt++ & 1) 1429 fdsetpos(sc, sc->cachetrk, 0); 1430 else 1431 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1432 /* 1433 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and DMA 1434 */ 1435 if (loopcnt < 8) 1436 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1437 else { 1438 loopcnt = 0; 1439 fdc_indma = NULL; 1440 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1441 fddmastart(sc, sc->cachetrk); 1442 } 1443 } 1444 1445 void 1446 fddmadone(struct fd_softc *sc, int timeo) 1447 { 1448 #ifdef FDDEBUG 1449 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1450 #endif 1451 fdc_indma = NULL; 1452 callout_stop(&sc->motor_ch); 1453 FDDMASTOP; 1454 1455 /* 1456 * guarantee the drive has been at current head and cyl 1457 * for at least FDWRITEDELAY after a write. 1458 */ 1459 if (sc->flags & FDF_WRITEWAIT) { 1460 delay(FDWRITEDELAY); 1461 sc->flags &= ~FDF_WRITEWAIT; 1462 } 1463 1464 if ((sc->flags & FDF_MOTOROFF) == 0) { 1465 /* 1466 * motor runs for 1.5 seconds after last DMA 1467 */ 1468 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1469 } 1470 if (sc->flags & FDF_DIRTY) { 1471 /* 1472 * if buffer dirty, the last DMA cleaned it 1473 */ 1474 sc->flags &= ~FDF_DIRTY; 1475 if (timeo) 1476 printf("%s: write of track cache timed out.\n", 1477 sc->sc_dv.dv_xname); 1478 if (sc->flags & FDF_JUSTFLUSH) { 1479 sc->flags &= ~FDF_JUSTFLUSH; 1480 /* 1481 * we are done DMA'ing 1482 */ 1483 fddone(sc); 1484 return; 1485 } 1486 /* 1487 * load the cache 1488 */ 1489 fddmastart(sc, sc->cachetrk); 1490 return; 1491 } 1492 #ifdef FDDEBUG 1493 else if (sc->flags & FDF_MOTOROFF) 1494 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1495 #endif 1496 1497 /* 1498 * cache loaded decode it into cache buffer 1499 */ 1500 if (timeo == 0 && fdrawtocache(sc) == 0) 1501 sc->retried = 0; 1502 else { 1503 #ifdef FDDEBUG 1504 if (timeo) 1505 printf("%s: fddmadone: cache load timed out.\n", 1506 sc->sc_dv.dv_xname); 1507 #endif 1508 if (sc->retried >= sc->retries) { 1509 sc->retried = 0; 1510 sc->cachetrk = -1; 1511 } else { 1512 sc->retried++; 1513 /* 1514 * this will be restarted at end of calibrate loop. 1515 */ 1516 callout_stop(&sc->motor_ch); 1517 fdcalibrate(sc); 1518 return; 1519 } 1520 } 1521 fddone(sc); 1522 } 1523 1524 void 1525 fddone(struct fd_softc *sc) 1526 { 1527 struct buf *dp, *bp; 1528 char *data; 1529 int sz; 1530 1531 #ifdef FDDEBUG 1532 printf("fddone: unit %d\n", sc->hwunit); 1533 #endif 1534 /* 1535 * check to see if unit is just flushing the cache, 1536 * that is we have no io queued. 1537 */ 1538 if (sc->flags & FDF_MOTOROFF) 1539 goto nobuf; 1540 1541 dp = &sc->curbuf; 1542 if ((bp = BUFQ_PEEK(sc->bufq)) == NULL) 1543 panic ("fddone"); 1544 /* 1545 * check for an error that may have occurred 1546 * while getting the track. 1547 */ 1548 if (sc->cachetrk == -1) { 1549 sc->retried = 0; 1550 bp->b_flags |= B_ERROR; 1551 bp->b_error = EIO; 1552 } else if ((bp->b_flags & B_ERROR) == 0) { 1553 data = sc->cachep; 1554 /* 1555 * get offset of data in track cache and limit 1556 * the copy size to not exceed the cache's end. 1557 */ 1558 data += (dp->b_blkno % sc->nsectors) * FDSECSIZE; 1559 sz = sc->nsectors - dp->b_blkno % sc->nsectors; 1560 sz *= FDSECSIZE; 1561 sz = min(dp->b_bcount, sz); 1562 if (bp->b_flags & B_READ) 1563 bcopy(data, dp->b_data, sz); 1564 else { 1565 bcopy(dp->b_data, data, sz); 1566 sc->flags |= FDF_DIRTY; 1567 } 1568 bp->b_resid = dp->b_bcount - sz; 1569 if (bp->b_resid == 0) { 1570 bp->b_error = 0; 1571 } else { 1572 /* 1573 * not done yet need to read next track 1574 */ 1575 fdcont(sc); 1576 return; 1577 } 1578 } 1579 /* 1580 * remove from queue. 1581 */ 1582 (void)BUFQ_GET(sc->bufq); 1583 1584 disk_unbusy(&sc->dkdev, (bp->b_bcount - bp->b_resid), 1585 (bp->b_flags & B_READ)); 1586 1587 biodone(bp); 1588 nobuf: 1589 fdfindwork(device_unit(&sc->sc_dv)); 1590 } 1591 1592 void 1593 fdfindwork(int unit) 1594 { 1595 struct fd_softc *ssc, *sc; 1596 int i, last; 1597 1598 /* 1599 * first see if we have any fdopen()'s waiting 1600 */ 1601 if (fdc_wantwakeup) { 1602 wakeup(fdopen); 1603 fdc_wantwakeup--; 1604 return; 1605 } 1606 1607 /* 1608 * start next available unit, linear search from the next unit 1609 * wrapping and finally this unit. 1610 */ 1611 last = 0; 1612 ssc = NULL; 1613 for (i = unit + 1; last == 0; i++) { 1614 if (i == unit) 1615 last = 1; 1616 if (i >= fd_cd.cd_ndevs) { 1617 i = -1; 1618 continue; 1619 } 1620 if ((sc = fd_cd.cd_devs[i]) == NULL) 1621 continue; 1622 1623 /* 1624 * if unit has requested to be turned off 1625 * and it has no buf's queued do it now 1626 */ 1627 if (sc->flags & FDF_MOTOROFF) { 1628 if (BUFQ_PEEK(sc->bufq) == NULL) 1629 fdmotoroff(sc); 1630 else { 1631 /* 1632 * we gained a buf request while 1633 * we waited, forget the motoroff 1634 */ 1635 sc->flags &= ~FDF_MOTOROFF; 1636 } 1637 /* 1638 * if we now have DMA unit must have needed 1639 * flushing, quit 1640 */ 1641 if (fdc_indma) 1642 return; 1643 } 1644 /* 1645 * if we have no start unit and the current unit has 1646 * io waiting choose this unit to start. 1647 */ 1648 if (ssc == NULL && BUFQ_PEEK(sc->bufq) != NULL) 1649 ssc = sc; 1650 } 1651 if (ssc) 1652 fdstart(ssc); 1653 } 1654 1655 /* 1656 * min byte count to whats left of the track in question 1657 */ 1658 void 1659 fdminphys(struct buf *bp) 1660 { 1661 struct fd_softc *sc; 1662 int trk, sec, toff, tsz; 1663 1664 if ((sc = getsoftc(fd_cd, FDUNIT(bp->b_dev))) == NULL) 1665 panic("fdminphys: couldn't get softc"); 1666 1667 trk = bp->b_blkno / sc->nsectors; 1668 sec = bp->b_blkno % sc->nsectors; 1669 1670 toff = sec * FDSECSIZE; 1671 tsz = sc->nsectors * FDSECSIZE; 1672 #ifdef FDDEBUG 1673 printf("fdminphys: before %ld", bp->b_bcount); 1674 #endif 1675 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1676 #ifdef FDDEBUG 1677 printf(" after %ld\n", bp->b_bcount); 1678 #endif 1679 minphys(bp); 1680 } 1681 1682 /* 1683 * encode the track cache into raw MFM ready for DMA 1684 * when we go to multiple disk formats, this will call type dependent 1685 * functions 1686 */ 1687 void fdcachetoraw(struct fd_softc *sc) 1688 { 1689 if (sc->openpart == FDMSDOSPART) 1690 mscachetoraw(sc); 1691 else 1692 amcachetoraw(sc); 1693 } 1694 1695 /* 1696 * decode raw MFM from DMA into units track cache. 1697 * when we go to multiple disk formats, this will call type dependent 1698 * functions 1699 */ 1700 int 1701 fdrawtocache(struct fd_softc *sc) 1702 { 1703 1704 if (sc->openpart == FDMSDOSPART) 1705 return(msrawtocache(sc)); 1706 else 1707 return(amrawtocache(sc)); 1708 } 1709 1710 void 1711 amcachetoraw(struct fd_softc *sc) 1712 { 1713 static u_long mfmnull[4]; 1714 u_long *rp, *crp, *dp, hcksum, dcksum, info, zero; 1715 int sec, i; 1716 1717 rp = fdc_dmap; 1718 1719 /* 1720 * not yet one sector (- 1 long) gap. 1721 * for now use previous drivers values 1722 */ 1723 for (i = 0; i < sc->type->gap; i++) 1724 *rp++ = 0xaaaaaaaa; 1725 /* 1726 * process sectors 1727 */ 1728 dp = sc->cachep; 1729 zero = 0; 1730 info = 0xff000000 | (sc->cachetrk << 16) | sc->nsectors; 1731 for (sec = 0; sec < sc->nsectors; sec++, info += (1 << 8) - 1) { 1732 hcksum = dcksum = 0; 1733 /* 1734 * sector format 1735 * offset description 1736 *----------------------------------- 1737 * 0 null 1738 * 1 sync 1739 * oddbits evenbits 1740 *---------------------- 1741 * 2 3 [0xff]b [trk]b [sec]b [togap]b 1742 * 4-7 8-11 null 1743 * 12 13 header cksum [2-11] 1744 * 14 15 data cksum [16-271] 1745 * 16-143 144-271 data 1746 */ 1747 *rp = 0xaaaaaaaa; 1748 if (*(rp - 1) & 0x1) 1749 *rp &= 0x7fffffff; /* clock bit correction */ 1750 rp++; 1751 *rp++ = (FDMFMSYNC << 16) | FDMFMSYNC; 1752 rp = mfmblkencode(&info, rp, &hcksum, 1); 1753 rp = mfmblkencode(mfmnull, rp, &hcksum, 4); 1754 rp = mfmblkencode(&hcksum, rp, NULL, 1); 1755 1756 crp = rp; 1757 rp = mfmblkencode(dp, rp + 2, &dcksum, FDSECLWORDS); 1758 dp += FDSECLWORDS; 1759 crp = mfmblkencode(&dcksum, crp, NULL, 1); 1760 if (*(crp - 1) & 0x1) 1761 *crp &= 0x7fffffff; /* clock bit correction */ 1762 else if ((*crp & 0x40000000) == 0) 1763 *crp |= 0x80000000; 1764 } 1765 *rp = 0xaaa80000; 1766 if (*(rp - 1) & 0x1) 1767 *rp &= 0x7fffffff; 1768 } 1769 1770 u_long * 1771 fdfindsync(u_long *rp, u_long *ep) 1772 { 1773 u_short *sp; 1774 1775 sp = (u_short *)rp; 1776 while ((u_long *)sp < ep && *sp != FDMFMSYNC) 1777 sp++; 1778 while ((u_long *)sp < ep && *sp == FDMFMSYNC) 1779 sp++; 1780 if ((u_long *)sp < ep) 1781 return((u_long *)sp); 1782 return(NULL); 1783 } 1784 1785 int 1786 amrawtocache(struct fd_softc *sc) 1787 { 1788 u_long mfmnull[4]; 1789 u_long *dp, *rp, *erp, *crp, *srp, hcksum, dcksum, info, cktmp; 1790 int cnt, doagain; 1791 1792 doagain = 1; 1793 srp = rp = fdc_dmap; 1794 erp = (u_long *)((u_short *)rp + sc->type->nreadw); 1795 cnt = 0; 1796 again: 1797 if (doagain == 0 || (rp = srp = fdfindsync(srp, erp)) == NULL) { 1798 #ifdef DIAGNOSTIC 1799 printf("%s: corrupted track (%d) data.\n", 1800 sc->sc_dv.dv_xname, sc->cachetrk); 1801 #endif 1802 return(-1); 1803 } 1804 1805 /* 1806 * process sectors 1807 */ 1808 for (; cnt < sc->nsectors; cnt++) { 1809 hcksum = dcksum = 0; 1810 rp = mfmblkdecode(rp, &info, &hcksum, 1); 1811 rp = mfmblkdecode(rp, mfmnull, &hcksum, 4); 1812 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1813 if (cktmp != hcksum) { 1814 #ifdef FDDEBUG 1815 printf(" info 0x%lx hchksum 0x%lx trkhcksum 0x%lx\n", 1816 info, hcksum, cktmp); 1817 #endif 1818 goto again; 1819 } 1820 if (((info >> 16) & 0xff) != sc->cachetrk) { 1821 #ifdef DEBUG 1822 printf("%s: incorrect track found: 0x%lx %d\n", 1823 sc->sc_dv.dv_xname, info, sc->cachetrk); 1824 #endif 1825 goto again; 1826 } 1827 #ifdef FDDEBUG 1828 printf(" info 0x%lx\n", info); 1829 #endif 1830 1831 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1832 dp = sc->cachep; 1833 dp += FDSECLWORDS * ((info >> 8) & 0xff); 1834 crp = mfmblkdecode(rp, dp, &dcksum, FDSECLWORDS); 1835 if (cktmp != dcksum) { 1836 #ifdef FDDEBUG 1837 printf(" info 0x%lx dchksum 0x%lx trkdcksum 0x%lx\n", 1838 info, dcksum, cktmp); 1839 #endif 1840 goto again; 1841 } 1842 1843 /* 1844 * if we are at gap then we can no longer be sure 1845 * of correct sync marks 1846 */ 1847 if ((info && 0xff) == 1) 1848 doagain = 1; 1849 else 1850 doagain = 0; 1851 srp = rp = fdfindsync(crp, erp); 1852 } 1853 return(0); 1854 } 1855 1856 void 1857 mscachetoraw(struct fd_softc *sc) 1858 { 1859 u_short *rp, *erp, crc; 1860 u_char *cp, tb[5]; 1861 int sec, i; 1862 1863 rp = (u_short *)fdc_dmap; 1864 erp = rp + sc->type->nwritew; 1865 cp = sc->cachep; 1866 1867 /* 1868 * initial track filler (828 * GAP1) 1869 */ 1870 for (i = 0; i < sc->type->gap; i++) { 1871 *rp++ = FDMFMGAP1; 1872 *rp++ = FDMFMGAP1; 1873 } 1874 1875 for (sec = 0; sec < sc->nsectors; sec++) { 1876 1877 /* 1878 * leading sector gap 1879 * (12 * GAP2) + (3 * SYNC) 1880 */ 1881 for (i = 0; i < 12; i++) 1882 *rp++ = FDMFMGAP2; 1883 *rp++ = FDMFMSYNC; 1884 *rp++ = FDMFMSYNC; 1885 *rp++ = FDMFMSYNC; 1886 1887 /* 1888 * sector information 1889 * (ID) + track + side + sector + sector size + CRC16 1890 */ 1891 *rp++ = FDMFMID; 1892 tb[0] = sc->cachetrk / FDNHEADS; 1893 tb[1] = sc->cachetrk % FDNHEADS; 1894 tb[2] = sec + 1; 1895 i = sc->bytespersec; 1896 tb[3] = i < 256 ? 0 : (i < 512 ? 1 : (i < 1024 ? 2 : 3)); 1897 rp = msblkencode(rp, tb, 4, &crc); 1898 tb[0] = crc >> 8; 1899 tb[1] = crc & 0xff; 1900 tb[2] = 0x4e; /* GAP1 decoded */ 1901 rp = msblkencode(rp, tb, 3, 0); 1902 1903 /* 1904 * sector info/data gap 1905 * (22 * GAP1) + (12 * GAP2) + (3 * SYNC) 1906 */ 1907 for (i = 0; i < 21; i++) 1908 *rp++ = FDMFMGAP1; 1909 for (i = 0; i < 12; i++) 1910 *rp++ = FDMFMGAP2; 1911 *rp++ = FDMFMSYNC; 1912 *rp++ = FDMFMSYNC; 1913 *rp++ = FDMFMSYNC; 1914 1915 /* 1916 * sector data 1917 * (DATA) + ...data... + CRC16 1918 */ 1919 *rp++ = FDMFMDATA; 1920 rp = msblkencode(rp, cp, sc->bytespersec, &crc); 1921 cp += sc->bytespersec; 1922 tb[0] = crc >> 8; 1923 tb[1] = crc & 0xff; 1924 tb[2] = 0x4e; /* GAP3 decoded */ 1925 rp = msblkencode(rp, tb, 3, 0); 1926 1927 /* 1928 * trailing sector gap 1929 * (80 * GAP3) 1930 */ 1931 for (i = 0; i < 79; i++) 1932 *rp++ = FDMFMGAP3; 1933 } 1934 1935 /* 1936 * fill rest of track with GAP3 1937 */ 1938 while (rp != erp) 1939 *rp++ = FDMFMGAP3; 1940 1941 } 1942 1943 int 1944 msrawtocache(struct fd_softc *sc) 1945 { 1946 u_short *rp, *srp, *erp; 1947 u_char tb[5], *cp; 1948 int ct, sec, retry; 1949 1950 srp = rp = (u_short *)fdc_dmap; 1951 erp = rp + sc->type->nreadw; 1952 cp = sc->cachep; 1953 1954 for (ct = 0; ct < sc->nsectors; ct++) { 1955 retry = 1; 1956 do { 1957 /* 1958 * skip leading gap to sync 1959 */ 1960 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) { 1961 #ifdef DIAGNOSTIC 1962 printf("%s: corrupted track (%d) data.\n", 1963 sc->sc_dv.dv_xname, sc->cachetrk); 1964 #endif 1965 return(-1); 1966 } 1967 1968 /* 1969 * Grab sector info 1970 */ 1971 if (*rp++ != FDMFMID) 1972 continue; 1973 rp = msblkdecode(rp, tb, 4); 1974 #ifdef FDDEBUG 1975 printf("sector id: sector %d, track %d, side %d," 1976 "bps %d\n", tb[2], tb[0], tb[1], 128 << tb[3]); 1977 #endif 1978 if ((tb[0] * FDNHEADS + tb[1]) != sc->cachetrk || 1979 tb[2] > sc->nsectors) 1980 continue; 1981 1982 sec = tb[2]; 1983 sc->bytespersec = 128 << tb[3]; 1984 rp += 2; /* skip CRC-16 */ 1985 1986 /* 1987 * skip gap and read in data 1988 */ 1989 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) 1990 return(-1); 1991 if (*rp++ != FDMFMDATA) 1992 continue; 1993 rp = msblkdecode(rp, cp + ((sec-1) * sc->bytespersec), 1994 sc->bytespersec); 1995 rp += 2; /* skip CRC-16 */ 1996 1997 retry = 0; 1998 } while (retry); 1999 } 2000 return(0); 2001 } 2002 2003 /* 2004 * encode len longwords of `dp' data in amiga mfm block format (`rp') 2005 * this format specified that the odd bits are at current pos and even 2006 * bits at len + current pos 2007 */ 2008 u_long * 2009 mfmblkencode(u_long *dp, u_long *rp, u_long *cp, int len) 2010 { 2011 u_long *sdp, *edp, d, dtmp, correct; 2012 2013 sdp = dp; 2014 edp = dp + len; 2015 2016 if (*(rp - 1) & 0x1) 2017 correct = 1; 2018 else 2019 correct = 0; 2020 /* 2021 * do odd bits 2022 */ 2023 while (dp < edp) { 2024 d = (*dp >> 1) & 0x55555555; /* remove clock bits */ 2025 dtmp = d ^ 0x55555555; 2026 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2027 /* 2028 * correct upper clock bit if needed 2029 */ 2030 if (correct) 2031 d &= 0x7fffffff; 2032 if (d & 0x1) 2033 correct = 1; 2034 else 2035 correct = 0; 2036 /* 2037 * do checksums and store in raw buffer 2038 */ 2039 if (cp) 2040 *cp ^= d; 2041 *rp++ = d; 2042 dp++; 2043 } 2044 /* 2045 * do even bits 2046 */ 2047 dp = sdp; 2048 while (dp < edp) { 2049 d = *dp & 0x55555555; /* remove clock bits */ 2050 dtmp = d ^ 0x55555555; 2051 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2052 /* 2053 * correct upper clock bit if needed 2054 */ 2055 if (correct) 2056 d &= 0x7fffffff; 2057 if (d & 0x1) 2058 correct = 1; 2059 else 2060 correct = 0; 2061 /* 2062 * do checksums and store in raw buffer 2063 */ 2064 if (cp) 2065 *cp ^= d; 2066 *rp++ = d; 2067 dp++; 2068 } 2069 if (cp) 2070 *cp &= 0x55555555; 2071 return(rp); 2072 } 2073 2074 /* 2075 * decode len longwords of `dp' data in amiga mfm block format (`rp') 2076 * this format specified that the odd bits are at current pos and even 2077 * bits at len + current pos 2078 */ 2079 u_long * 2080 mfmblkdecode(u_long *rp, u_long *dp, u_long *cp, int len) 2081 { 2082 u_long o, e; 2083 int cnt; 2084 2085 cnt = len; 2086 while (cnt--) { 2087 o = *rp; 2088 e = *(rp + len); 2089 if (cp) { 2090 *cp ^= o; 2091 *cp ^= e; 2092 } 2093 o &= 0x55555555; 2094 e &= 0x55555555; 2095 *dp++ = (o << 1) | e; 2096 rp++; 2097 } 2098 if (cp) 2099 *cp &= 0x55555555; 2100 return(rp + len); 2101 } 2102 2103 /* 2104 * decode len words in standard MFM format to len bytes 2105 * of data. 2106 */ 2107 u_short * 2108 msblkdecode(u_short *rp, u_char *cp, int len) 2109 { 2110 while (len--) { 2111 *cp++ = msdecode[*rp & 0x7f] | 2112 (msdecode[(*rp >> 8) & 0x7f] << 4); 2113 rp++; 2114 } 2115 2116 return(rp); 2117 } 2118 2119 /* 2120 * encode len bytes of data into len words in standard MFM format. 2121 * If a pointer is supplied for crc, calculate the CRC-16 of the data 2122 * as well. 2123 */ 2124 u_short * 2125 msblkencode(u_short *rp, u_char *cp, int len, u_short *crc) 2126 { 2127 u_short td; 2128 u_short mycrc; 2129 2130 /* preload crc for header (4 bytes) 2131 * or data (anything else) 2132 */ 2133 mycrc = (len == 4) ? 0xb230 : 0xe295; 2134 2135 while (len--) { 2136 td = (msencode[*cp >> 4] << 8) | msencode[*cp & 0x0f]; 2137 2138 /* Check for zeros in top bit of encode and bottom 2139 * bit of previous encode. if so, slap a one in betweem 2140 * them. 2141 */ 2142 if ((td & 0x140) == 0) 2143 td |= 0x80; 2144 if ((td & 0x4000) == 0 && (rp[-1] & 1) == 0) 2145 td |= 0x8000; 2146 2147 *rp++ = td; 2148 2149 /* 2150 * calc crc if requested 2151 */ 2152 if (crc) 2153 mycrc = (mycrc << 8) ^ mscrctab[*cp ^ (mycrc >> 8)]; 2154 2155 cp++; 2156 } 2157 2158 if (crc) 2159 *crc = mycrc; 2160 2161 return(rp); 2162 } 2163
Indexes created Thu Oct 02 14:10:14 GMT 2025