fd.c revision 1.69.2.2
1 /* $NetBSD: fd.c,v 1.69.2.2 2007/08/19 19:24:05 ad 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 1.69.2.2 2007/08/19 19:24:05 ad 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, 0); 403 callout_init(&sc->motor_ch, 0); 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, void *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 done; 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 done: 689 bp->b_resid = bp->b_bcount; 690 biodone(bp); 691 } 692 693 /* 694 * make sure disk is loaded and label is up-to-date. 695 */ 696 int 697 fdloaddisk(struct fd_softc *sc) 698 { 699 /* 700 * if diskchange is low step drive to 0 then up one then to zero. 701 */ 702 fdselunit(sc); /* make sure the unit is selected */ 703 if (FDTESTC(FDB_CHANGED)) { 704 fdsetpos(sc, 0, 0); 705 sc->cachetrk = -1; /* invalidate the cache */ 706 sc->flags &= ~FDF_HAVELABEL; 707 fdsetpos(sc, FDNHEADS, 0); 708 fdsetpos(sc, 0, 0); 709 if (FDTESTC(FDB_CHANGED)) { 710 fdmotoroff(sc); 711 FDDESELECT(sc->unitmask); 712 return(ENXIO); 713 } 714 } 715 FDDESELECT(sc->unitmask); 716 fdmotoroff(sc); 717 sc->type = fdcgetfdtype(sc->hwunit); 718 if (sc->type == NULL) 719 return(ENXIO); 720 if (sc->openpart == FDMSDOSPART) 721 sc->nsectors = sc->type->msdos_nsectors; 722 else 723 sc->nsectors = sc->type->amiga_nsectors; 724 return(0); 725 } 726 727 void 728 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 729 /* (variable part) XXX ick */ 730 { 731 732 bzero(lp, sizeof(struct disklabel)); 733 lp->d_secsize = FDSECSIZE; 734 lp->d_ntracks = FDNHEADS; 735 lp->d_ncylinders = sc->type->ncylinders; 736 lp->d_nsectors = sc->nsectors; 737 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 738 lp->d_type = DTYPE_FLOPPY; 739 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 740 lp->d_rpm = 300; /* good guess I suppose. */ 741 lp->d_interleave = 1; /* should change when adding msdos */ 742 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 743 lp->d_bbsize = 0; 744 lp->d_sbsize = 0; 745 lp->d_partitions[part].p_size = lp->d_secperunit; 746 lp->d_partitions[part].p_fstype = FS_UNUSED; 747 lp->d_partitions[part].p_fsize = 1024; 748 lp->d_partitions[part].p_frag = 8; 749 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 750 lp->d_npartitions = part + 1; 751 lp->d_magic = lp->d_magic2 = DISKMAGIC; 752 lp->d_checksum = dkcksum(lp); 753 } 754 755 /* 756 * read disk label, if present otherwise create one 757 * return a new label if raw part and none found, otherwise err. 758 */ 759 int 760 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 761 { 762 struct disklabel *lp, *dlp; 763 struct cpu_disklabel *clp; 764 struct buf *bp; 765 int error, part; 766 767 if (sc->flags & FDF_HAVELABEL && 768 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 769 return(0); 770 #ifdef FDDEBUG 771 printf("fdgetdisklabel()\n"); 772 #endif 773 part = FDPART(dev); 774 lp = sc->dkdev.dk_label; 775 clp = sc->dkdev.dk_cpulabel; 776 bzero(lp, sizeof(struct disklabel)); 777 bzero(clp, sizeof(struct cpu_disklabel)); 778 779 lp->d_secsize = FDSECSIZE; 780 lp->d_ntracks = FDNHEADS; 781 lp->d_ncylinders = sc->type->ncylinders; 782 lp->d_nsectors = sc->nsectors; 783 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 784 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 785 lp->d_npartitions = part + 1; 786 lp->d_partitions[part].p_size = lp->d_secperunit; 787 lp->d_partitions[part].p_fstype = FS_UNUSED; 788 lp->d_partitions[part].p_fsize = 1024; 789 lp->d_partitions[part].p_frag = 8; 790 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 791 792 sc->flags |= FDF_HAVELABEL; 793 794 bp = (void *)geteblk((int)lp->d_secsize); 795 bp->b_dev = dev; 796 bp->b_blkno = 0; 797 bp->b_cylinder = 0; 798 bp->b_bcount = FDSECSIZE; 799 bp->b_flags |= B_READ; 800 fdstrategy(bp); 801 if ((error = biowait(bp)) != 0) 802 goto nolabel; 803 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 804 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 805 dkcksum(dlp)) { 806 error = EINVAL; 807 goto nolabel; 808 } 809 bcopy(dlp, lp, sizeof(struct disklabel)); 810 if (lp->d_trkseek > FDSTEPDELAY) 811 sc->stepdelay = lp->d_trkseek; 812 brelse(bp); 813 return(0); 814 nolabel: 815 fdgetdefaultlabel(sc, lp, part); 816 brelse(bp); 817 return(0); 818 } 819 820 /* 821 * set the incore copy of this units disklabel 822 */ 823 int 824 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 825 { 826 struct disklabel *clp; 827 struct partition *pp; 828 829 /* 830 * must have at least opened raw unit to fetch the 831 * raw_part stuff. 832 */ 833 if ((sc->flags & FDF_HAVELABEL) == 0) 834 return(EINVAL); 835 clp = sc->dkdev.dk_label; 836 /* 837 * make sure things check out and we only have one valid 838 * partition 839 */ 840 #ifdef FDDEBUG 841 printf("fdsetdisklabel\n"); 842 #endif 843 if (lp->d_secsize != FDSECSIZE || 844 lp->d_nsectors != clp->d_nsectors || 845 lp->d_ntracks != FDNHEADS || 846 lp->d_ncylinders != clp->d_ncylinders || 847 lp->d_secpercyl != clp->d_secpercyl || 848 lp->d_secperunit != clp->d_secperunit || 849 lp->d_magic != DISKMAGIC || 850 lp->d_magic2 != DISKMAGIC || 851 lp->d_npartitions == 0 || 852 lp->d_npartitions > FDMAXPARTS || 853 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 854 dkcksum(lp)) 855 return(EINVAL); 856 /* 857 * if any partitions are present make sure they 858 * represent the currently open type 859 */ 860 if ((pp = &lp->d_partitions[0])->p_size) { 861 if ((pp = &lp->d_partitions[1])->p_size == 0) 862 goto done; 863 else if (sc->openpart != 1) 864 return(EINVAL); 865 } else if (sc->openpart != 0) 866 return(EINVAL); 867 /* 868 * make sure selected partition is within bounds 869 * XXX on the second check, its to handle a bug in 870 * XXX the cluster routines as they require mutliples 871 * XXX of PAGE_SIZE currently 872 */ 873 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 874 (pp->p_frag * pp->p_fsize % PAGE_SIZE)) 875 return(EINVAL); 876 done: 877 bcopy(lp, clp, sizeof(struct disklabel)); 878 return(0); 879 } 880 881 /* 882 * write out the incore copy of this units disklabel 883 */ 884 int 885 fdputdisklabel(struct fd_softc *sc, dev_t dev) 886 { 887 struct disklabel *lp, *dlp; 888 struct buf *bp; 889 int error; 890 891 if ((sc->flags & FDF_HAVELABEL) == 0) 892 return(EBADF); 893 #ifdef FDDEBUG 894 printf("fdputdisklabel\n"); 895 #endif 896 /* 897 * get buf and read in sector 0 898 */ 899 lp = sc->dkdev.dk_label; 900 bp = geteblk((int)lp->d_secsize); 901 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 902 bp->b_blkno = 0; 903 bp->b_cylinder = 0; 904 bp->b_bcount = FDSECSIZE; 905 bp->b_flags |= B_READ; 906 fdstrategy(bp); 907 if ((error = biowait(bp)) != 0) 908 goto done; 909 /* 910 * copy disklabel to buf and write it out synchronous 911 */ 912 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 913 bcopy(lp, dlp, sizeof(struct disklabel)); 914 bp->b_blkno = 0; 915 bp->b_cylinder = 0; 916 bp->b_flags &= ~(B_READ|B_DONE); 917 bp->b_flags |= B_WRITE; 918 fdstrategy(bp); 919 error = biowait(bp); 920 done: 921 brelse(bp); 922 return(error); 923 } 924 925 /* 926 * figure out drive type or NULL if none. 927 */ 928 struct fdtype * 929 fdcgetfdtype(int unit) 930 { 931 struct fdtype *ftp; 932 u_long id, idb; 933 int cnt, umask; 934 935 id = 0; 936 umask = 1 << (3 + unit); 937 938 FDDESELECT(FDCUNITMASK); 939 940 FDSETMOTOR(1); 941 delay(1); 942 FDSELECT(umask); 943 delay(1); 944 FDDESELECT(umask); 945 946 FDSETMOTOR(0); 947 delay(1); 948 FDSELECT(umask); 949 delay(1); 950 FDDESELECT(umask); 951 952 for (idb = 0x80000000; idb; idb >>= 1) { 953 FDSELECT(umask); 954 delay(1); 955 if (FDTESTC(FDB_READY) == 0) 956 id |= idb; 957 FDDESELECT(umask); 958 delay(1); 959 } 960 #ifdef FDDEBUG 961 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 962 #endif 963 964 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 965 if (ftp->driveid == id) 966 return(ftp); 967 /* 968 * 3.5dd's at unit 0 do not always return id. 969 */ 970 if (unit == 0) 971 return(fdtype); 972 return(NULL); 973 } 974 975 /* 976 * turn motor off if possible otherwise mark as needed and will be done 977 * later. 978 */ 979 void 980 fdmotoroff(void *arg) 981 { 982 struct fd_softc *sc; 983 int s; 984 985 sc = arg; 986 s = splbio(); 987 988 #ifdef FDDEBUG 989 printf("fdmotoroff: unit %d\n", sc->hwunit); 990 #endif 991 if ((sc->flags & FDF_MOTORON) == 0) 992 goto done; 993 /* 994 * if we have a timeout on a DMA operation let fddmadone() 995 * deal with it. 996 */ 997 if (fdc_indma == sc) { 998 fddmadone(sc, 1); 999 goto done; 1000 } 1001 #ifdef FDDEBUG 1002 printf(" motor was on, turning off\n"); 1003 #endif 1004 1005 /* 1006 * flush cache if needed 1007 */ 1008 if (sc->flags & FDF_DIRTY) { 1009 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1010 #ifdef FDDEBUG 1011 printf(" flushing dirty buffer first\n"); 1012 #endif 1013 /* 1014 * if DMA'ing done for now, fddone() will call us again 1015 */ 1016 if (fdc_indma) 1017 goto done; 1018 fddmastart(sc, sc->cachetrk); 1019 goto done; 1020 } 1021 1022 /* 1023 * if controller is busy just schedule us to be called back 1024 */ 1025 if (fdc_indma) { 1026 /* 1027 * someone else has the controller now 1028 * just set flag and let fddone() call us again. 1029 */ 1030 sc->flags |= FDF_MOTOROFF; 1031 goto done; 1032 } 1033 1034 #ifdef FDDEBUG 1035 printf(" hw turning unit off\n"); 1036 #endif 1037 1038 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1039 FDDESELECT(FDCUNITMASK); 1040 FDSETMOTOR(0); 1041 delay(1); 1042 FDSELECT(sc->unitmask); 1043 delay(4); 1044 FDDESELECT(sc->unitmask); 1045 delay(1); 1046 if (sc->flags & FDF_WMOTOROFF) 1047 wakeup(fdmotoroff); 1048 done: 1049 splx(s); 1050 } 1051 1052 /* 1053 * select drive seek to track exit with motor on. 1054 * fdsetpos(x, 0, 0) does calibrates the drive. 1055 */ 1056 void 1057 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1058 { 1059 int nstep, sdir, ondly, ncyl, nside; 1060 1061 FDDESELECT(FDCUNITMASK); 1062 FDSETMOTOR(1); 1063 delay(1); 1064 FDSELECT(sc->unitmask); 1065 delay(1); 1066 if ((sc->flags & FDF_MOTORON) == 0) { 1067 ondly = 0; 1068 while (FDTESTC(FDB_READY) == 0) { 1069 delay(1000); 1070 if (++ondly >= 1000) 1071 break; 1072 } 1073 } 1074 sc->flags |= FDF_MOTORON; 1075 1076 ncyl = trk / FDNHEADS; 1077 nside = trk % FDNHEADS; 1078 1079 if (sc->curcyl == ncyl && fdc_side == nside) 1080 return; 1081 1082 if (towrite) 1083 sc->flags |= FDF_WRITEWAIT; 1084 1085 #ifdef FDDEBUG 1086 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1087 trk % FDNHEADS, towrite); 1088 #endif 1089 nstep = ncyl - sc->curcyl; 1090 if (nstep) { 1091 /* 1092 * figure direction 1093 */ 1094 if (nstep > 0 && ncyl != 0) { 1095 sdir = FDSTEPIN; 1096 FDSETDIR(1); 1097 } else { 1098 nstep = -nstep; 1099 sdir = FDSTEPOUT; 1100 FDSETDIR(0); 1101 } 1102 if (ncyl == 0) { 1103 /* 1104 * either just want cylinder 0 or doing 1105 * a calibrate. 1106 */ 1107 nstep = 256; 1108 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1109 FDSTEP; 1110 delay(sc->stepdelay); 1111 } 1112 if (nstep < 0) 1113 sc->flags |= FDF_NOTRACK0; 1114 } else { 1115 /* 1116 * step the needed amount amount. 1117 */ 1118 while (nstep--) { 1119 FDSTEP; 1120 delay(sc->stepdelay); 1121 } 1122 } 1123 /* 1124 * if switched directions 1125 * allow drive to settle. 1126 */ 1127 if (sc->pstepdir != sdir) 1128 delay(FDSETTLEDELAY); 1129 sc->pstepdir = sdir; 1130 sc->curcyl = ncyl; 1131 } 1132 if (nside == fdc_side) 1133 return; 1134 /* 1135 * select side 1136 */ 1137 fdc_side = nside; 1138 FDSETHEAD(nside); 1139 delay(FDPRESIDEDELAY); 1140 } 1141 1142 void 1143 fdselunit(struct fd_softc *sc) 1144 { 1145 FDDESELECT(FDCUNITMASK); /* deselect all */ 1146 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1147 delay(1); 1148 FDSELECT(sc->unitmask); /* select unit */ 1149 delay(1); 1150 } 1151 1152 /* 1153 * process next buf on device queue. 1154 * normall sequence of events: 1155 * fdstart() -> fddmastart(); 1156 * fdidxintr(); 1157 * fdintr() -> fddmadone() -> fddone(); 1158 * if the track is in the cache then fdstart() will short-circuit 1159 * to fddone() else if the track cache is dirty it will flush. If 1160 * the buf is not an entire track it will cache the requested track. 1161 */ 1162 void 1163 fdstart(struct fd_softc *sc) 1164 { 1165 int trk, error, write; 1166 struct buf *bp, *dp; 1167 int changed; 1168 1169 #ifdef FDDEBUG 1170 printf("fdstart: unit %d\n", sc->hwunit); 1171 #endif 1172 1173 /* 1174 * if DMA'ing just return. we must have been called from fdstartegy. 1175 */ 1176 if (fdc_indma) 1177 return; 1178 1179 /* 1180 * get next buf if there. 1181 */ 1182 dp = &sc->curbuf; 1183 if ((bp = BUFQ_PEEK(sc->bufq)) == NULL) { 1184 #ifdef FDDEBUG 1185 printf(" nothing to do\n"); 1186 #endif 1187 return; 1188 } 1189 1190 /* 1191 * Mark us as busy now, in case fddone() gets called in one 1192 * of the cases below. 1193 */ 1194 disk_busy(&sc->dkdev); 1195 1196 /* 1197 * make sure same disk is loaded 1198 */ 1199 fdselunit(sc); 1200 changed = FDTESTC(FDB_CHANGED); 1201 FDDESELECT(sc->unitmask); 1202 if (changed) { 1203 /* 1204 * disk missing, invalidate all future io on 1205 * this unit until re-open()'ed also invalidate 1206 * all current io 1207 */ 1208 printf("fdstart: disk changed\n"); 1209 #ifdef FDDEBUG 1210 printf(" disk was removed invalidating all io\n"); 1211 #endif 1212 sc->flags &= ~FDF_HAVELABEL; 1213 for (;;) { 1214 bp = BUFQ_GET(sc->bufq); 1215 bp->b_flags |= B_ERROR; 1216 bp->b_error = EIO; 1217 if (BUFQ_PEEK(sc->bufq) == NULL) 1218 break; 1219 biodone(bp); 1220 } 1221 /* 1222 * do fddone() on last buf to allow other units to start. 1223 */ 1224 BUFQ_PUT(sc->bufq, bp); 1225 fddone(sc); 1226 return; 1227 } 1228 1229 /* 1230 * we have a valid buf, setup our local version 1231 * we use this count to allow reading over multiple tracks. 1232 * into a single buffer 1233 */ 1234 dp->b_bcount = bp->b_bcount; 1235 dp->b_blkno = bp->b_blkno; 1236 dp->b_data = bp->b_data; 1237 dp->b_flags = bp->b_flags; 1238 dp->b_resid = 0; 1239 1240 if (bp->b_flags & B_READ) 1241 write = 0; 1242 else if (FDTESTC(FDB_PROTECT) == 0) 1243 write = 1; 1244 else { 1245 error = EPERM; 1246 goto done; 1247 } 1248 1249 /* 1250 * figure trk given blkno 1251 */ 1252 trk = bp->b_blkno / sc->nsectors; 1253 1254 /* 1255 * check to see if same as currently cached track 1256 * if so we need to do no DMA read. 1257 */ 1258 if (trk == sc->cachetrk) { 1259 fddone(sc); 1260 return; 1261 } 1262 1263 /* 1264 * if we will be overwriting the entire cache, don't bother to 1265 * fetch it. 1266 */ 1267 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1268 bp->b_blkno % sc->nsectors == 0) { 1269 if (sc->flags & FDF_DIRTY) 1270 sc->flags |= FDF_JUSTFLUSH; 1271 else { 1272 sc->cachetrk = trk; 1273 fddone(sc); 1274 return; 1275 } 1276 } 1277 1278 /* 1279 * start DMA read of `trk' 1280 */ 1281 fddmastart(sc, trk); 1282 return; 1283 done: 1284 bp->b_error = error; 1285 fddone(sc); 1286 } 1287 1288 /* 1289 * continue a started operation on next track. always begin at 1290 * sector 0 on the next track. 1291 */ 1292 void 1293 fdcont(struct fd_softc *sc) 1294 { 1295 struct buf *dp, *bp; 1296 int trk, write; 1297 1298 dp = &sc->curbuf; 1299 bp = BUFQ_PEEK(sc->bufq); 1300 dp->b_data = (char*)dp->b_data + (dp->b_bcount - bp->b_resid); 1301 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1302 dp->b_bcount = bp->b_resid; 1303 1304 /* 1305 * figure trk given blkno 1306 */ 1307 trk = dp->b_blkno / sc->nsectors; 1308 #ifdef DEBUG 1309 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1310 panic("fdcont: confused"); 1311 #endif 1312 if (dp->b_flags & B_READ) 1313 write = 0; 1314 else 1315 write = 1; 1316 /* 1317 * if we will be overwriting the entire cache, don't bother to 1318 * fetch it. 1319 */ 1320 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1321 if (sc->flags & FDF_DIRTY) 1322 sc->flags |= FDF_JUSTFLUSH; 1323 else { 1324 sc->cachetrk = trk; 1325 fddone(sc); 1326 return; 1327 } 1328 } 1329 /* 1330 * start DMA read of `trk' 1331 */ 1332 fddmastart(sc, trk); 1333 return; 1334 } 1335 1336 void 1337 fddmastart(struct fd_softc *sc, int trk) 1338 { 1339 int adkmask, ndmaw, write, dmatrk; 1340 1341 #ifdef FDDEBUG 1342 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1343 trk / FDNHEADS, trk % FDNHEADS); 1344 #endif 1345 /* 1346 * flush the cached track if dirty else read requested track. 1347 */ 1348 if (sc->flags & FDF_DIRTY) { 1349 fdcachetoraw(sc); 1350 ndmaw = sc->type->nwritew; 1351 dmatrk = sc->cachetrk; 1352 write = 1; 1353 } else { 1354 ndmaw = sc->type->nreadw; 1355 dmatrk = trk; 1356 write = 0; 1357 } 1358 1359 #ifdef FDDEBUG 1360 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1361 #endif 1362 sc->cachetrk = trk; 1363 fdc_indma = sc; 1364 fdsetpos(sc, dmatrk, write); 1365 1366 /* 1367 * setup dma stuff 1368 */ 1369 if (write == 0) { 1370 custom.adkcon = ADKF_MSBSYNC; 1371 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1372 custom.dsksync = FDMFMSYNC; 1373 } else { 1374 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1375 ADKF_MSBSYNC; 1376 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1377 if (dmatrk >= sc->type->precomp[0]) 1378 adkmask |= ADKF_PRECOMP0; 1379 if (dmatrk >= sc->type->precomp[1]) 1380 adkmask |= ADKF_PRECOMP1; 1381 custom.adkcon = adkmask; 1382 } 1383 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1384 1385 /* 1386 * If writing an MSDOS track, activate disk index pulse 1387 * interrupt, DMA will be started in the intr routine fdidxintr() 1388 * Otherwise, start the DMA here. 1389 */ 1390 if (write && sc->openpart == FDMSDOSPART) { 1391 fdc_dmalen = ndmaw; 1392 fdc_dmawrite = write; 1393 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1394 } else { 1395 FDDMASTART(ndmaw, write); 1396 fdc_dmalen = 0; 1397 } 1398 1399 #ifdef FDDEBUG 1400 printf(" DMA started\n"); 1401 #endif 1402 } 1403 1404 /* 1405 * recalibrate the drive 1406 */ 1407 void 1408 fdcalibrate(void *arg) 1409 { 1410 struct fd_softc *sc; 1411 static int loopcnt; 1412 1413 sc = arg; 1414 1415 if (loopcnt == 0) { 1416 /* 1417 * seek cyl 0 1418 */ 1419 fdc_indma = sc; 1420 sc->stepdelay += 900; 1421 if (sc->cachetrk > 1) 1422 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1423 sc->stepdelay -= 900; 1424 } 1425 if (loopcnt++ & 1) 1426 fdsetpos(sc, sc->cachetrk, 0); 1427 else 1428 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1429 /* 1430 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and DMA 1431 */ 1432 if (loopcnt < 8) 1433 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1434 else { 1435 loopcnt = 0; 1436 fdc_indma = NULL; 1437 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1438 fddmastart(sc, sc->cachetrk); 1439 } 1440 } 1441 1442 void 1443 fddmadone(struct fd_softc *sc, int timeo) 1444 { 1445 #ifdef FDDEBUG 1446 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1447 #endif 1448 fdc_indma = NULL; 1449 callout_stop(&sc->motor_ch); 1450 FDDMASTOP; 1451 1452 /* 1453 * guarantee the drive has been at current head and cyl 1454 * for at least FDWRITEDELAY after a write. 1455 */ 1456 if (sc->flags & FDF_WRITEWAIT) { 1457 delay(FDWRITEDELAY); 1458 sc->flags &= ~FDF_WRITEWAIT; 1459 } 1460 1461 if ((sc->flags & FDF_MOTOROFF) == 0) { 1462 /* 1463 * motor runs for 1.5 seconds after last DMA 1464 */ 1465 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1466 } 1467 if (sc->flags & FDF_DIRTY) { 1468 /* 1469 * if buffer dirty, the last DMA cleaned it 1470 */ 1471 sc->flags &= ~FDF_DIRTY; 1472 if (timeo) 1473 printf("%s: write of track cache timed out.\n", 1474 sc->sc_dv.dv_xname); 1475 if (sc->flags & FDF_JUSTFLUSH) { 1476 sc->flags &= ~FDF_JUSTFLUSH; 1477 /* 1478 * we are done DMA'ing 1479 */ 1480 fddone(sc); 1481 return; 1482 } 1483 /* 1484 * load the cache 1485 */ 1486 fddmastart(sc, sc->cachetrk); 1487 return; 1488 } 1489 #ifdef FDDEBUG 1490 else if (sc->flags & FDF_MOTOROFF) 1491 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1492 #endif 1493 1494 /* 1495 * cache loaded decode it into cache buffer 1496 */ 1497 if (timeo == 0 && fdrawtocache(sc) == 0) 1498 sc->retried = 0; 1499 else { 1500 #ifdef FDDEBUG 1501 if (timeo) 1502 printf("%s: fddmadone: cache load timed out.\n", 1503 sc->sc_dv.dv_xname); 1504 #endif 1505 if (sc->retried >= sc->retries) { 1506 sc->retried = 0; 1507 sc->cachetrk = -1; 1508 } else { 1509 sc->retried++; 1510 /* 1511 * this will be restarted at end of calibrate loop. 1512 */ 1513 callout_stop(&sc->motor_ch); 1514 fdcalibrate(sc); 1515 return; 1516 } 1517 } 1518 fddone(sc); 1519 } 1520 1521 void 1522 fddone(struct fd_softc *sc) 1523 { 1524 struct buf *dp, *bp; 1525 char *data; 1526 int sz; 1527 1528 #ifdef FDDEBUG 1529 printf("fddone: unit %d\n", sc->hwunit); 1530 #endif 1531 /* 1532 * check to see if unit is just flushing the cache, 1533 * that is we have no io queued. 1534 */ 1535 if (sc->flags & FDF_MOTOROFF) 1536 goto nobuf; 1537 1538 dp = &sc->curbuf; 1539 if ((bp = BUFQ_PEEK(sc->bufq)) == NULL) 1540 panic ("fddone"); 1541 /* 1542 * check for an error that may have occurred 1543 * while getting the track. 1544 */ 1545 if (sc->cachetrk == -1) { 1546 sc->retried = 0; 1547 bp->b_error = EIO; 1548 } else if (bp->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(device_unit(&sc->sc_dv)); 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 %ld", bp->b_bcount); 1670 #endif 1671 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1672 #ifdef FDDEBUG 1673 printf(" after %ld\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%lx hchksum 0x%lx trkhcksum 0x%lx\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%lx\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%lx dchksum 0x%lx trkdcksum 0x%lx\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