fd.c revision 1.84.4.1
1 /* $NetBSD: fd.c,v 1.84.4.1 2011/03/05 20:49:21 rmind 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 1.84.4.1 2011/03/05 20:49:21 rmind 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 <machine/cpu.h> 55 #include <amiga/amiga/device.h> 56 #include <amiga/amiga/custom.h> 57 #include <amiga/amiga/cia.h> 58 #include <amiga/amiga/cc.h> 59 60 #include "locators.h" 61 62 enum fdc_bits { FDB_CHANGED = 2, FDB_PROTECT, FDB_CYLZERO, FDB_READY }; 63 /* 64 * partitions in fd represent different format floppies 65 * partition a is 0 etc.. 66 */ 67 enum fd_parttypes { 68 FDAMIGAPART = 0, 69 FDMSDOSPART, 70 FDMAXPARTS 71 }; 72 73 #define FDBBSIZE (8192) 74 #define FDSBSIZE (8192) 75 76 #define FDUNIT(dev) DISKUNIT(dev) 77 #define FDPART(dev) DISKPART(dev) 78 #define FDMAKEDEV(m, u, p) MAKEDISKDEV((m), (u), (p)) 79 80 /* that's nice, but we don't want to always use this as an amiga drive 81 bunghole :-) */ 82 #define FDNHEADS (2) /* amiga drives always have 2 heads */ 83 #define FDSECSIZE (512) /* amiga drives always have 512 byte sectors */ 84 #define FDSECLWORDS (128) 85 86 #define FDSETTLEDELAY (18000) /* usec delay after seeking after switch dir */ 87 #define FDSTEPDELAY (3500) /* usec delay after steping */ 88 #define FDPRESIDEDELAY (1000) /* usec delay before writing can occur */ 89 #define FDWRITEDELAY (1300) /* usec delay after write */ 90 91 #define FDSTEPOUT (1) /* decrease track step */ 92 #define FDSTEPIN (0) /* increase track step */ 93 94 #define FDCUNITMASK (0x78) /* mask for all units (bits 6-3) */ 95 96 #define FDRETRIES (2) /* default number of retries */ 97 #define FDMAXUNITS (4) /* maximum number of supported units */ 98 99 #define DISKLEN_READ (0) /* fake mask for reading */ 100 #define DISKLEN_WRITE (1 << 14) /* bit for writing */ 101 #define DISKLEN_DMAEN (1 << 15) /* DMA go */ 102 #define DMABUFSZ ((DISKLEN_WRITE - 1) * 2) /* largest DMA possible */ 103 104 #define FDMFMSYNC (0x4489) 105 #define FDMFMID (0x5554) 106 #define FDMFMDATA (0x5545) 107 #define FDMFMGAP1 (0x9254) 108 #define FDMFMGAP2 (0xAAAA) 109 #define FDMFMGAP3 (0x9254) 110 #define CRC16POLY (0x1021) /* (x^16) + x^12 + x^5 + x^0 */ 111 112 /* 113 * Msdos-type MFM encode/decode 114 */ 115 static u_char msdecode[128]; 116 static u_char msencode[16] = 117 { 118 0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15, 119 0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55 120 }; 121 static u_short mscrctab[256]; 122 123 /* 124 5554 aaaa aaaa aaa5 2aa4 4452 aa51 125 00 00 03 02 ac 0d 126 */ 127 128 /* 129 * floppy device type 130 */ 131 struct fdtype { 132 u_int driveid; /* drive identification (from drive) */ 133 u_int ncylinders; /* number of cylinders on drive */ 134 u_int amiga_nsectors; /* number of sectors per amiga track */ 135 u_int msdos_nsectors; /* number of sectors per msdos track */ 136 u_int nreadw; /* number of words (short) read per track */ 137 u_int nwritew; /* number of words (short) written per track */ 138 u_int gap; /* track gap size in long words */ 139 const u_int precomp[2]; /* 1st and 2nd precomp values */ 140 const char *desc; /* description of drive type (useq) */ 141 }; 142 143 /* 144 * floppy disk device data 145 */ 146 struct fd_softc { 147 struct device sc_dv; /* generic device info; must come first */ 148 struct disk dkdev; /* generic disk info */ 149 struct bufq_state *bufq;/* queue pending I/O operations */ 150 struct buf curbuf; /* state of current I/O operation */ 151 struct callout calibrate_ch; 152 struct callout motor_ch; 153 struct fdtype *type; 154 void *cachep; /* cached track data (write through) */ 155 int cachetrk; /* cahced track -1 for none */ 156 int hwunit; /* unit for amiga controlling hw */ 157 int unitmask; /* mask for cia select deslect */ 158 int pstepdir; /* previous step direction */ 159 int curcyl; /* current curcyl head positioned on */ 160 int flags; /* misc flags */ 161 int wlabel; 162 int stepdelay; /* useq to delay after seek user setable */ 163 int nsectors; /* number of sectors per track */ 164 int openpart; /* which partition [ab] == [12] is open */ 165 short retries; /* number of times to retry failed io */ 166 short retried; /* number of times current io retried */ 167 int bytespersec; /* number of bytes per sector */ 168 }; 169 170 /* fd_softc->flags */ 171 #define FDF_MOTORON (0x01) /* motor is running */ 172 #define FDF_MOTOROFF (0x02) /* motor is waiting to be turned off */ 173 #define FDF_WMOTOROFF (0x04) /* unit wants a wakeup after off */ 174 #define FDF_DIRTY (0x08) /* track cache needs write */ 175 #define FDF_WRITEWAIT (0x10) /* need to head select delay on next setpos */ 176 #define FDF_HAVELABEL (0x20) /* label is valid */ 177 #define FDF_JUSTFLUSH (0x40) /* don't bother caching track. */ 178 #define FDF_NOTRACK0 (0x80) /* was not able to recalibrate drive */ 179 180 int fdc_wantwakeup; 181 int fdc_side; 182 void *fdc_dmap; 183 struct fd_softc *fdc_indma; 184 int fdc_dmalen; 185 int fdc_dmawrite; 186 187 struct fdcargs { 188 struct fdtype *type; 189 int unit; 190 }; 191 192 int fdcmatch(struct device *, struct cfdata *, void *); 193 void fdcattach(struct device *, struct device *, void *); 194 int fdcprint(void *, const char *); 195 int fdmatch(struct device *, struct cfdata *, void *); 196 void fdattach(struct device *, struct device *, void *); 197 198 void fdintr(int); 199 void fdidxintr(void); 200 int fdloaddisk(struct fd_softc *); 201 void fdgetdefaultlabel(struct fd_softc *, struct disklabel *, int); 202 int fdgetdisklabel(struct fd_softc *, dev_t); 203 int fdsetdisklabel(struct fd_softc *, struct disklabel *); 204 int fdputdisklabel(struct fd_softc *, dev_t); 205 struct fdtype * fdcgetfdtype(int); 206 void fdmotoroff(void *); 207 void fdsetpos(struct fd_softc *, int, int); 208 void fdselunit(struct fd_softc *); 209 void fdstart(struct fd_softc *); 210 void fdcont(struct fd_softc *); 211 void fddmastart(struct fd_softc *, int); 212 void fdcalibrate(void *); 213 void fddmadone(struct fd_softc *, int); 214 void fddone(struct fd_softc *); 215 void fdfindwork(int); 216 void fdminphys(struct buf *); 217 void fdcachetoraw(struct fd_softc *); 218 void amcachetoraw(struct fd_softc *); 219 int amrawtocache(struct fd_softc *); 220 u_long *fdfindsync(u_long *, u_long *); 221 int fdrawtocache(struct fd_softc *); 222 void mscachetoraw(struct fd_softc *); 223 int msrawtocache(struct fd_softc *); 224 u_long *mfmblkencode(u_long *, u_long *, u_long *, int); 225 u_long *mfmblkdecode(u_long *, u_long *, u_long *, int); 226 u_short *msblkdecode(u_short *, u_char *, int); 227 u_short *msblkencode(u_short *, u_char *, int, u_short *); 228 229 /* 230 * read size is (nsectors + 1) * mfm secsize + gap bytes + 2 shorts 231 * write size is nsectors * mfm secsize + gap bytes + 3 shorts 232 * the extra shorts are to deal with a DMA hw bug in the controller 233 * they are probably too much (I belive the bug is 1 short on write and 234 * 3 bits on read) but there is no need to be cheap here. 235 */ 236 #define MAXTRKSZ (22 * FDSECSIZE) 237 struct fdtype fdtype[] = { 238 { 0x00000000, 80, 11, 9, 7358, 6815, 414, { 80, 161 }, "3.5dd" }, 239 { 0x55555555, 40, 11, 9, 7358, 6815, 414, { 80, 161 }, "5.25dd" }, 240 { 0xAAAAAAAA, 80, 22, 18, 14716, 13630, 828, { 80, 161 }, "3.5hd" } 241 }; 242 int nfdtype = __arraycount(fdtype); 243 244 CFATTACH_DECL(fd, sizeof(struct fd_softc), 245 fdmatch, fdattach, NULL, NULL); 246 247 extern struct cfdriver fd_cd; 248 249 dev_type_open(fdopen); 250 dev_type_close(fdclose); 251 dev_type_read(fdread); 252 dev_type_write(fdwrite); 253 dev_type_ioctl(fdioctl); 254 dev_type_strategy(fdstrategy); 255 256 const struct bdevsw fd_bdevsw = { 257 fdopen, fdclose, fdstrategy, fdioctl, nodump, nosize, D_DISK 258 }; 259 260 const struct cdevsw fd_cdevsw = { 261 fdopen, fdclose, fdread, fdwrite, fdioctl, 262 nostop, notty, nopoll, nommap, nokqfilter, D_DISK 263 }; 264 265 struct dkdriver fddkdriver = { fdstrategy }; 266 267 CFATTACH_DECL(fdc, sizeof(struct device), 268 fdcmatch, fdcattach, NULL, NULL); 269 270 /* 271 * all hw access through macros, this helps to hide the active low 272 * properties 273 */ 274 275 #define FDUNITMASK(unit) (1 << (3 + (unit))) 276 277 /* 278 * select units using mask 279 */ 280 #define FDSELECT(um) do { ciab.prb &= ~(um); } while (0) 281 282 /* 283 * deselect units using mask 284 */ 285 #define FDDESELECT(um) do { ciab.prb |= (um); delay(1); } while (0) 286 287 /* 288 * test hw condition bits 289 */ 290 #define FDTESTC(bit) ((ciaa.pra & (1 << (bit))) == 0) 291 292 /* 293 * set motor for select units, true motor on else off 294 */ 295 #define FDSETMOTOR(on) do { \ 296 if (on) ciab.prb &= ~CIAB_PRB_MTR; else ciab.prb |= CIAB_PRB_MTR; \ 297 } while (0) 298 299 /* 300 * set head for select units 301 */ 302 #define FDSETHEAD(head) do { \ 303 if (head) ciab.prb &= ~CIAB_PRB_SIDE; else ciab.prb |= CIAB_PRB_SIDE; \ 304 delay(1); } while (0) 305 306 /* 307 * select direction, true towards spindle else outwards 308 */ 309 #define FDSETDIR(in) do { \ 310 if (in) ciab.prb &= ~CIAB_PRB_DIR; else ciab.prb |= CIAB_PRB_DIR; \ 311 delay(1); } while (0) 312 313 /* 314 * step the selected units 315 */ 316 #define FDSTEP do { \ 317 ciab.prb &= ~CIAB_PRB_STEP; ciab.prb |= CIAB_PRB_STEP; \ 318 } while (0) 319 320 #define FDDMASTART(len, towrite) do { \ 321 int dmasz = (len) | ((towrite) ? DISKLEN_WRITE : 0) | DISKLEN_DMAEN; \ 322 custom.dsklen = dmasz; custom.dsklen = dmasz; } while (0) 323 324 #define FDDMASTOP do { custom.dsklen = 0; } while (0) 325 326 327 int 328 fdcmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 329 { 330 static int fdc_matched = 0; 331 332 /* Allow only once instance. */ 333 if (matchname("fdc", auxp) == 0 || fdc_matched) 334 return(0); 335 if ((fdc_dmap = alloc_chipmem(DMABUFSZ)) == NULL) { 336 printf("fdc: unable to allocate DMA buffer\n"); 337 return(0); 338 } 339 340 fdc_matched = 1; 341 return(1); 342 } 343 344 void 345 fdcattach(struct device *pdp, struct device *dp, void *auxp) 346 { 347 struct fdcargs args; 348 349 printf(": dmabuf pa 0x%x", (unsigned)kvtop(fdc_dmap)); 350 printf(": dmabuf ka %p\n", fdc_dmap); 351 args.unit = 0; 352 args.type = fdcgetfdtype(args.unit); 353 354 fdc_side = -1; 355 config_found(dp, &args, fdcprint); 356 for (args.unit++; args.unit < FDMAXUNITS; args.unit++) { 357 if ((args.type = fdcgetfdtype(args.unit)) == NULL) 358 continue; 359 config_found(dp, &args, fdcprint); 360 } 361 } 362 363 int 364 fdcprint(void *auxp, const char *pnp) 365 { 366 struct fdcargs *fcp; 367 368 fcp = auxp; 369 if (pnp) 370 aprint_normal("fd%d at %s unit %d:", fcp->unit, pnp, 371 fcp->type->driveid); 372 return(UNCONF); 373 } 374 375 /*ARGSUSED*/ 376 int 377 fdmatch(struct device *pdp, struct cfdata *cfp, void *auxp) 378 { 379 struct fdcargs *fdap; 380 381 fdap = auxp; 382 if (cfp->cf_loc[FDCCF_UNIT] == fdap->unit || 383 cfp->cf_loc[FDCCF_UNIT] == FDCCF_UNIT_DEFAULT) 384 return(1); 385 386 return(0); 387 } 388 389 void 390 fdattach(struct device *pdp, struct device *dp, void *auxp) 391 { 392 struct fdcargs *ap; 393 struct fd_softc *sc; 394 int i; 395 396 ap = auxp; 397 sc = device_private(dp); 398 399 bufq_alloc(&sc->bufq, "disksort", BUFQ_SORT_CYLINDER); 400 callout_init(&sc->calibrate_ch, 0); 401 callout_init(&sc->motor_ch, 0); 402 403 sc->curcyl = sc->cachetrk = -1; 404 sc->openpart = -1; 405 sc->type = ap->type; 406 sc->hwunit = ap->unit; 407 sc->unitmask = 1 << (3 + ap->unit); 408 sc->retries = FDRETRIES; 409 sc->stepdelay = FDSTEPDELAY; 410 sc->bytespersec = 512; 411 printf(" unit %d: %s %d cyl, %d head, %d sec [%d sec], 512 bytes/sec\n", 412 sc->hwunit, sc->type->desc, sc->type->ncylinders, FDNHEADS, 413 sc->type->amiga_nsectors, sc->type->msdos_nsectors); 414 415 /* 416 * Initialize and attach the disk structure. 417 */ 418 disk_init(&sc->dkdev, sc->sc_dv.dv_xname, &fddkdriver); 419 disk_attach(&sc->dkdev); 420 421 /* 422 * calibrate the drive 423 */ 424 fdsetpos(sc, 0, 0); 425 fdsetpos(sc, sc->type->ncylinders, 0); 426 fdsetpos(sc, 0, 0); 427 fdmotoroff(sc); 428 429 /* 430 * precalc msdos MFM and CRC 431 */ 432 for (i = 0; i < 128; i++) 433 msdecode[i] = 0xff; 434 for (i = 0; i < 16; i++) 435 msdecode[msencode[i]] = i; 436 for (i = 0; i < 256; i++) { 437 mscrctab[i] = (0x1021 * (i & 0xf0)) ^ (0x1021 * (i & 0x0f)) ^ 438 (0x1021 * (i >> 4)); 439 } 440 441 /* 442 * enable disk related interrupts 443 */ 444 custom.dmacon = DMAF_SETCLR | DMAF_MASTER | DMAF_DISK; 445 custom.intena = INTF_SETCLR | INTF_DSKBLK; 446 ciab.icr = CIA_ICR_FLG; 447 } 448 449 /*ARGSUSED*/ 450 int 451 fdopen(dev_t dev, int flags, int devtype, struct lwp *l) 452 { 453 struct fd_softc *sc; 454 int wasopen, fwork, error, s; 455 456 error = 0; 457 458 if (FDPART(dev) >= FDMAXPARTS) 459 return(ENXIO); 460 461 if ((sc = getsoftc(fd_cd, FDUNIT(dev))) == NULL) 462 return(ENXIO); 463 if (sc->flags & FDF_NOTRACK0) 464 return(ENXIO); 465 if (sc->cachep == NULL) 466 sc->cachep = malloc(MAXTRKSZ, M_DEVBUF, M_WAITOK); 467 468 s = splbio(); 469 /* 470 * if we are sleeping in fdclose(); waiting for a chance to 471 * shut the motor off, do a sleep here also. 472 */ 473 while (sc->flags & FDF_WMOTOROFF) 474 tsleep(fdmotoroff, PRIBIO, "fdopen", 0); 475 476 fwork = 0; 477 /* 478 * if not open let user open request type, otherwise 479 * ensure they are trying to open same type. 480 */ 481 if (sc->openpart == FDPART(dev)) 482 wasopen = 1; 483 else if (sc->openpart == -1) { 484 sc->openpart = FDPART(dev); 485 wasopen = 0; 486 } else { 487 wasopen = 1; 488 error = EPERM; 489 goto done; 490 } 491 492 /* 493 * wait for current io to complete if any 494 */ 495 if (fdc_indma) { 496 fwork = 1; 497 fdc_wantwakeup++; 498 tsleep(fdopen, PRIBIO, "fdopen", 0); 499 } 500 if ((error = fdloaddisk(sc)) != 0) 501 goto done; 502 if ((error = fdgetdisklabel(sc, dev)) != 0) 503 goto done; 504 #ifdef FDDEBUG 505 printf(" open successful\n"); 506 #endif 507 done: 508 /* 509 * if we requested that fddone()->fdfindwork() wake us, allow it to 510 * complete its job now 511 */ 512 if (fwork) 513 fdfindwork(FDUNIT(dev)); 514 splx(s); 515 516 /* 517 * if we were not open and we marked us so reverse that. 518 */ 519 if (error && wasopen == 0) 520 sc->openpart = -1; 521 return(error); 522 } 523 524 /*ARGSUSED*/ 525 int 526 fdclose(dev_t dev, int flags, int devtype, struct lwp *l) 527 { 528 struct fd_softc *sc; 529 int s; 530 531 #ifdef FDDEBUG 532 printf("fdclose()\n"); 533 #endif 534 sc = getsoftc(fd_cd, FDUNIT(dev)); 535 s = splbio(); 536 if (sc->flags & FDF_MOTORON) { 537 sc->flags |= FDF_WMOTOROFF; 538 tsleep(fdmotoroff, PRIBIO, "fdclose", 0); 539 sc->flags &= ~FDF_WMOTOROFF; 540 wakeup(fdmotoroff); 541 } 542 sc->openpart = -1; 543 splx(s); 544 return(0); 545 } 546 547 int 548 fdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l) 549 { 550 struct fd_softc *sc; 551 int error, wlab; 552 553 sc = getsoftc(fd_cd, FDUNIT(dev)); 554 555 if ((sc->flags & FDF_HAVELABEL) == 0) 556 return(EBADF); 557 558 switch (cmd) { 559 case DIOCSBAD: 560 return(EINVAL); 561 case DIOCSRETRIES: 562 if (*(int *)addr < 0) 563 return(EINVAL); 564 sc->retries = *(int *)addr; 565 return(0); 566 case DIOCSSTEP: 567 if (*(int *)addr < FDSTEPDELAY) 568 return(EINVAL); 569 sc->dkdev.dk_label->d_trkseek = sc->stepdelay = *(int *)addr; 570 return(0); 571 case DIOCGDINFO: 572 *(struct disklabel *)addr = *(sc->dkdev.dk_label); 573 return(0); 574 case DIOCGPART: 575 ((struct partinfo *)addr)->disklab = sc->dkdev.dk_label; 576 ((struct partinfo *)addr)->part = 577 &sc->dkdev.dk_label->d_partitions[FDPART(dev)]; 578 return(0); 579 case DIOCSDINFO: 580 if ((flag & FWRITE) == 0) 581 return(EBADF); 582 return(fdsetdisklabel(sc, (struct disklabel *)addr)); 583 case DIOCWDINFO: 584 if ((flag & FWRITE) == 0) 585 return(EBADF); 586 if ((error = fdsetdisklabel(sc, (struct disklabel *)addr)) != 0) 587 return(error); 588 wlab = sc->wlabel; 589 sc->wlabel = 1; 590 error = fdputdisklabel(sc, dev); 591 sc->wlabel = wlab; 592 return(error); 593 case DIOCWLABEL: 594 if ((flag & FWRITE) == 0) 595 return(EBADF); 596 sc->wlabel = *(int *)addr; 597 return(0); 598 case DIOCGDEFLABEL: 599 fdgetdefaultlabel(sc, (struct disklabel *)addr, FDPART(dev)); 600 return(0); 601 default: 602 return(ENOTTY); 603 } 604 } 605 606 int 607 fdread(dev_t dev, struct uio *uio, int flags) 608 { 609 return (physio(fdstrategy, NULL, dev, B_READ, fdminphys, uio)); 610 } 611 612 int 613 fdwrite(dev_t dev, struct uio *uio, int flags) 614 { 615 return (physio(fdstrategy, NULL, dev, B_WRITE, fdminphys, uio)); 616 } 617 618 619 void 620 fdintr(int flag) 621 { 622 int s; 623 624 s = splbio(); 625 if (fdc_indma) 626 fddmadone(fdc_indma, 0); 627 splx(s); 628 } 629 630 void 631 fdidxintr(void) 632 { 633 if (fdc_indma && fdc_dmalen) { 634 /* 635 * turn off intr and start actual dma 636 */ 637 ciab.icr = CIA_ICR_FLG; 638 FDDMASTART(fdc_dmalen, fdc_dmawrite); 639 fdc_dmalen = 0; 640 } 641 } 642 643 void 644 fdstrategy(struct buf *bp) 645 { 646 struct disklabel *lp; 647 struct fd_softc *sc; 648 int unit, part, s; 649 650 unit = FDUNIT(bp->b_dev); 651 part = FDPART(bp->b_dev); 652 sc = getsoftc(fd_cd, unit); 653 654 #ifdef FDDEBUG 655 printf("fdstrategy: %p\n", bp); 656 #endif 657 /* 658 * check for valid partition and bounds 659 */ 660 lp = sc->dkdev.dk_label; 661 if ((sc->flags & FDF_HAVELABEL) == 0) { 662 bp->b_error = EIO; 663 goto done; 664 } 665 if (bounds_check_with_label(&sc->dkdev, bp, sc->wlabel) <= 0) 666 goto done; 667 668 /* 669 * trans count of zero or bounds check indicates io is done 670 * we are done. 671 */ 672 if (bp->b_bcount == 0) 673 goto done; 674 675 bp->b_rawblkno = bp->b_blkno; 676 677 /* 678 * queue the buf and kick the low level code 679 */ 680 s = splbio(); 681 bufq_put(sc->bufq, bp); 682 fdstart(sc); 683 splx(s); 684 return; 685 done: 686 bp->b_resid = bp->b_bcount; 687 biodone(bp); 688 } 689 690 /* 691 * make sure disk is loaded and label is up-to-date. 692 */ 693 int 694 fdloaddisk(struct fd_softc *sc) 695 { 696 /* 697 * if diskchange is low step drive to 0 then up one then to zero. 698 */ 699 fdselunit(sc); /* make sure the unit is selected */ 700 if (FDTESTC(FDB_CHANGED)) { 701 fdsetpos(sc, 0, 0); 702 sc->cachetrk = -1; /* invalidate the cache */ 703 sc->flags &= ~FDF_HAVELABEL; 704 fdsetpos(sc, FDNHEADS, 0); 705 fdsetpos(sc, 0, 0); 706 if (FDTESTC(FDB_CHANGED)) { 707 fdmotoroff(sc); 708 FDDESELECT(sc->unitmask); 709 return(ENXIO); 710 } 711 } 712 FDDESELECT(sc->unitmask); 713 fdmotoroff(sc); 714 sc->type = fdcgetfdtype(sc->hwunit); 715 if (sc->type == NULL) 716 return(ENXIO); 717 if (sc->openpart == FDMSDOSPART) 718 sc->nsectors = sc->type->msdos_nsectors; 719 else 720 sc->nsectors = sc->type->amiga_nsectors; 721 return(0); 722 } 723 724 void 725 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 726 /* (variable part) XXX ick */ 727 { 728 729 memset(lp, 0, sizeof(struct disklabel)); 730 lp->d_secsize = FDSECSIZE; 731 lp->d_ntracks = FDNHEADS; 732 lp->d_ncylinders = sc->type->ncylinders; 733 lp->d_nsectors = sc->nsectors; 734 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 735 lp->d_type = DTYPE_FLOPPY; 736 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 737 lp->d_rpm = 300; /* good guess I suppose. */ 738 lp->d_interleave = 1; /* should change when adding msdos */ 739 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 740 lp->d_bbsize = 0; 741 lp->d_sbsize = 0; 742 lp->d_partitions[part].p_size = lp->d_secperunit; 743 lp->d_partitions[part].p_fstype = FS_UNUSED; 744 lp->d_partitions[part].p_fsize = 1024; 745 lp->d_partitions[part].p_frag = 8; 746 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 747 lp->d_npartitions = part + 1; 748 lp->d_magic = lp->d_magic2 = DISKMAGIC; 749 lp->d_checksum = dkcksum(lp); 750 } 751 752 /* 753 * read disk label, if present otherwise create one 754 * return a new label if raw part and none found, otherwise err. 755 */ 756 int 757 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 758 { 759 struct disklabel *lp, *dlp; 760 struct cpu_disklabel *clp; 761 struct buf *bp; 762 int error, part; 763 764 if (sc->flags & FDF_HAVELABEL && 765 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 766 return(0); 767 #ifdef FDDEBUG 768 printf("fdgetdisklabel()\n"); 769 #endif 770 part = FDPART(dev); 771 lp = sc->dkdev.dk_label; 772 clp = sc->dkdev.dk_cpulabel; 773 memset(lp, 0, sizeof(struct disklabel)); 774 memset(clp, 0, sizeof(struct cpu_disklabel)); 775 776 lp->d_secsize = FDSECSIZE; 777 lp->d_ntracks = FDNHEADS; 778 lp->d_ncylinders = sc->type->ncylinders; 779 lp->d_nsectors = sc->nsectors; 780 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 781 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 782 lp->d_npartitions = part + 1; 783 lp->d_partitions[part].p_size = lp->d_secperunit; 784 lp->d_partitions[part].p_fstype = FS_UNUSED; 785 lp->d_partitions[part].p_fsize = 1024; 786 lp->d_partitions[part].p_frag = 8; 787 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 788 789 sc->flags |= FDF_HAVELABEL; 790 791 bp = (void *)geteblk((int)lp->d_secsize); 792 bp->b_dev = dev; 793 bp->b_blkno = 0; 794 bp->b_cylinder = 0; 795 bp->b_bcount = FDSECSIZE; 796 bp->b_flags |= B_READ; 797 fdstrategy(bp); 798 if ((error = biowait(bp)) != 0) 799 goto nolabel; 800 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 801 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 802 dkcksum(dlp)) { 803 error = EINVAL; 804 goto nolabel; 805 } 806 memcpy(lp, dlp, sizeof(struct disklabel)); 807 if (lp->d_trkseek > FDSTEPDELAY) 808 sc->stepdelay = lp->d_trkseek; 809 brelse(bp, 0); 810 return(0); 811 nolabel: 812 fdgetdefaultlabel(sc, lp, part); 813 brelse(bp, 0); 814 return(0); 815 } 816 817 /* 818 * set the incore copy of this units disklabel 819 */ 820 int 821 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 822 { 823 struct disklabel *clp; 824 struct partition *pp; 825 826 /* 827 * must have at least opened raw unit to fetch the 828 * raw_part stuff. 829 */ 830 if ((sc->flags & FDF_HAVELABEL) == 0) 831 return(EINVAL); 832 clp = sc->dkdev.dk_label; 833 /* 834 * make sure things check out and we only have one valid 835 * partition 836 */ 837 #ifdef FDDEBUG 838 printf("fdsetdisklabel\n"); 839 #endif 840 if (lp->d_secsize != FDSECSIZE || 841 lp->d_nsectors != clp->d_nsectors || 842 lp->d_ntracks != FDNHEADS || 843 lp->d_ncylinders != clp->d_ncylinders || 844 lp->d_secpercyl != clp->d_secpercyl || 845 lp->d_secperunit != clp->d_secperunit || 846 lp->d_magic != DISKMAGIC || 847 lp->d_magic2 != DISKMAGIC || 848 lp->d_npartitions == 0 || 849 lp->d_npartitions > FDMAXPARTS || 850 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 851 dkcksum(lp)) 852 return(EINVAL); 853 /* 854 * if any partitions are present make sure they 855 * represent the currently open type 856 */ 857 if ((pp = &lp->d_partitions[0])->p_size) { 858 if ((pp = &lp->d_partitions[1])->p_size == 0) 859 goto done; 860 else if (sc->openpart != 1) 861 return(EINVAL); 862 } else if (sc->openpart != 0) 863 return(EINVAL); 864 /* 865 * make sure selected partition is within bounds 866 * XXX on the second check, its to handle a bug in 867 * XXX the cluster routines as they require mutliples 868 * XXX of PAGE_SIZE currently 869 */ 870 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 871 (pp->p_frag * pp->p_fsize % PAGE_SIZE)) 872 return(EINVAL); 873 done: 874 memcpy(clp, lp, sizeof(struct disklabel)); 875 return(0); 876 } 877 878 /* 879 * write out the incore copy of this units disklabel 880 */ 881 int 882 fdputdisklabel(struct fd_softc *sc, dev_t dev) 883 { 884 struct disklabel *lp, *dlp; 885 struct buf *bp; 886 int error; 887 888 if ((sc->flags & FDF_HAVELABEL) == 0) 889 return(EBADF); 890 #ifdef FDDEBUG 891 printf("fdputdisklabel\n"); 892 #endif 893 /* 894 * get buf and read in sector 0 895 */ 896 lp = sc->dkdev.dk_label; 897 bp = geteblk((int)lp->d_secsize); 898 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 899 bp->b_blkno = 0; 900 bp->b_cylinder = 0; 901 bp->b_bcount = FDSECSIZE; 902 bp->b_flags |= B_READ; 903 fdstrategy(bp); 904 if ((error = biowait(bp)) != 0) 905 goto done; 906 /* 907 * copy disklabel to buf and write it out synchronous 908 */ 909 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 910 memcpy(dlp, lp, sizeof(struct disklabel)); 911 bp->b_blkno = 0; 912 bp->b_cylinder = 0; 913 bp->b_flags &= ~(B_READ); 914 bp->b_oflags &= ~(BO_DONE); 915 bp->b_flags |= B_WRITE; 916 fdstrategy(bp); 917 error = biowait(bp); 918 done: 919 brelse(bp, 0); 920 return(error); 921 } 922 923 /* 924 * figure out drive type or NULL if none. 925 */ 926 struct fdtype * 927 fdcgetfdtype(int unit) 928 { 929 struct fdtype *ftp; 930 u_long id, idb; 931 int cnt, umask; 932 933 id = 0; 934 umask = 1 << (3 + unit); 935 936 FDDESELECT(FDCUNITMASK); 937 938 FDSETMOTOR(1); 939 delay(1); 940 FDSELECT(umask); 941 delay(1); 942 FDDESELECT(umask); 943 944 FDSETMOTOR(0); 945 delay(1); 946 FDSELECT(umask); 947 delay(1); 948 FDDESELECT(umask); 949 950 for (idb = 0x80000000; idb; idb >>= 1) { 951 FDSELECT(umask); 952 delay(1); 953 if (FDTESTC(FDB_READY) == 0) 954 id |= idb; 955 FDDESELECT(umask); 956 delay(1); 957 } 958 #ifdef FDDEBUG 959 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 960 #endif 961 962 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 963 if (ftp->driveid == id) 964 return(ftp); 965 /* 966 * 3.5dd's at unit 0 do not always return id. 967 */ 968 if (unit == 0) 969 return(fdtype); 970 return(NULL); 971 } 972 973 /* 974 * turn motor off if possible otherwise mark as needed and will be done 975 * later. 976 */ 977 void 978 fdmotoroff(void *arg) 979 { 980 struct fd_softc *sc; 981 int s; 982 983 sc = arg; 984 s = splbio(); 985 986 #ifdef FDDEBUG 987 printf("fdmotoroff: unit %d\n", sc->hwunit); 988 #endif 989 if ((sc->flags & FDF_MOTORON) == 0) 990 goto done; 991 /* 992 * if we have a timeout on a DMA operation let fddmadone() 993 * deal with it. 994 */ 995 if (fdc_indma == sc) { 996 fddmadone(sc, 1); 997 goto done; 998 } 999 #ifdef FDDEBUG 1000 printf(" motor was on, turning off\n"); 1001 #endif 1002 1003 /* 1004 * flush cache if needed 1005 */ 1006 if (sc->flags & FDF_DIRTY) { 1007 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1008 #ifdef FDDEBUG 1009 printf(" flushing dirty buffer first\n"); 1010 #endif 1011 /* 1012 * if DMA'ing done for now, fddone() will call us again 1013 */ 1014 if (fdc_indma) 1015 goto done; 1016 fddmastart(sc, sc->cachetrk); 1017 goto done; 1018 } 1019 1020 /* 1021 * if controller is busy just schedule us to be called back 1022 */ 1023 if (fdc_indma) { 1024 /* 1025 * someone else has the controller now 1026 * just set flag and let fddone() call us again. 1027 */ 1028 sc->flags |= FDF_MOTOROFF; 1029 goto done; 1030 } 1031 1032 #ifdef FDDEBUG 1033 printf(" hw turning unit off\n"); 1034 #endif 1035 1036 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1037 FDDESELECT(FDCUNITMASK); 1038 FDSETMOTOR(0); 1039 delay(1); 1040 FDSELECT(sc->unitmask); 1041 delay(4); 1042 FDDESELECT(sc->unitmask); 1043 delay(1); 1044 if (sc->flags & FDF_WMOTOROFF) 1045 wakeup(fdmotoroff); 1046 done: 1047 splx(s); 1048 } 1049 1050 /* 1051 * select drive seek to track exit with motor on. 1052 * fdsetpos(x, 0, 0) does calibrates the drive. 1053 */ 1054 void 1055 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1056 { 1057 int nstep, sdir, ondly, ncyl, nside; 1058 1059 FDDESELECT(FDCUNITMASK); 1060 FDSETMOTOR(1); 1061 delay(1); 1062 FDSELECT(sc->unitmask); 1063 delay(1); 1064 if ((sc->flags & FDF_MOTORON) == 0) { 1065 ondly = 0; 1066 while (FDTESTC(FDB_READY) == 0) { 1067 delay(1000); 1068 if (++ondly >= 1000) 1069 break; 1070 } 1071 } 1072 sc->flags |= FDF_MOTORON; 1073 1074 ncyl = trk / FDNHEADS; 1075 nside = trk % FDNHEADS; 1076 1077 if (sc->curcyl == ncyl && fdc_side == nside) 1078 return; 1079 1080 if (towrite) 1081 sc->flags |= FDF_WRITEWAIT; 1082 1083 #ifdef FDDEBUG 1084 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1085 trk % FDNHEADS, towrite); 1086 #endif 1087 nstep = ncyl - sc->curcyl; 1088 if (nstep) { 1089 /* 1090 * figure direction 1091 */ 1092 if (nstep > 0 && ncyl != 0) { 1093 sdir = FDSTEPIN; 1094 FDSETDIR(1); 1095 } else { 1096 nstep = -nstep; 1097 sdir = FDSTEPOUT; 1098 FDSETDIR(0); 1099 } 1100 if (ncyl == 0) { 1101 /* 1102 * either just want cylinder 0 or doing 1103 * a calibrate. 1104 */ 1105 nstep = 256; 1106 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1107 FDSTEP; 1108 delay(sc->stepdelay); 1109 } 1110 if (nstep < 0) 1111 sc->flags |= FDF_NOTRACK0; 1112 } else { 1113 /* 1114 * step the needed amount amount. 1115 */ 1116 while (nstep--) { 1117 FDSTEP; 1118 delay(sc->stepdelay); 1119 } 1120 } 1121 /* 1122 * if switched directions 1123 * allow drive to settle. 1124 */ 1125 if (sc->pstepdir != sdir) 1126 delay(FDSETTLEDELAY); 1127 sc->pstepdir = sdir; 1128 sc->curcyl = ncyl; 1129 } 1130 if (nside == fdc_side) 1131 return; 1132 /* 1133 * select side 1134 */ 1135 fdc_side = nside; 1136 FDSETHEAD(nside); 1137 delay(FDPRESIDEDELAY); 1138 } 1139 1140 void 1141 fdselunit(struct fd_softc *sc) 1142 { 1143 FDDESELECT(FDCUNITMASK); /* deselect all */ 1144 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1145 delay(1); 1146 FDSELECT(sc->unitmask); /* select unit */ 1147 delay(1); 1148 } 1149 1150 /* 1151 * process next buf on device queue. 1152 * normall sequence of events: 1153 * fdstart() -> fddmastart(); 1154 * fdidxintr(); 1155 * fdintr() -> fddmadone() -> fddone(); 1156 * if the track is in the cache then fdstart() will short-circuit 1157 * to fddone() else if the track cache is dirty it will flush. If 1158 * the buf is not an entire track it will cache the requested track. 1159 */ 1160 void 1161 fdstart(struct fd_softc *sc) 1162 { 1163 int trk, error, write; 1164 struct buf *bp, *dp; 1165 int changed; 1166 1167 #ifdef FDDEBUG 1168 printf("fdstart: unit %d\n", sc->hwunit); 1169 #endif 1170 1171 /* 1172 * if DMA'ing just return. we must have been called from fdstartegy. 1173 */ 1174 if (fdc_indma) 1175 return; 1176 1177 /* 1178 * get next buf if there. 1179 */ 1180 dp = &sc->curbuf; 1181 if ((bp = bufq_peek(sc->bufq)) == NULL) { 1182 #ifdef FDDEBUG 1183 printf(" nothing to do\n"); 1184 #endif 1185 return; 1186 } 1187 1188 /* 1189 * Mark us as busy now, in case fddone() gets called in one 1190 * of the cases below. 1191 */ 1192 disk_busy(&sc->dkdev); 1193 1194 /* 1195 * make sure same disk is loaded 1196 */ 1197 fdselunit(sc); 1198 changed = FDTESTC(FDB_CHANGED); 1199 FDDESELECT(sc->unitmask); 1200 if (changed) { 1201 /* 1202 * disk missing, invalidate all future io on 1203 * this unit until re-open()'ed also invalidate 1204 * all current io 1205 */ 1206 printf("fdstart: disk changed\n"); 1207 #ifdef FDDEBUG 1208 printf(" disk was removed invalidating all io\n"); 1209 #endif 1210 sc->flags &= ~FDF_HAVELABEL; 1211 for (;;) { 1212 bp = bufq_get(sc->bufq); 1213 bp->b_error = EIO; 1214 if (bufq_peek(sc->bufq) == NULL) 1215 break; 1216 biodone(bp); 1217 } 1218 /* 1219 * do fddone() on last buf to allow other units to start. 1220 */ 1221 bufq_put(sc->bufq, bp); 1222 fddone(sc); 1223 return; 1224 } 1225 1226 /* 1227 * we have a valid buf, setup our local version 1228 * we use this count to allow reading over multiple tracks. 1229 * into a single buffer 1230 */ 1231 dp->b_bcount = bp->b_bcount; 1232 dp->b_blkno = bp->b_blkno; 1233 dp->b_data = bp->b_data; 1234 dp->b_flags = bp->b_flags; 1235 dp->b_resid = 0; 1236 1237 if (bp->b_flags & B_READ) 1238 write = 0; 1239 else if (FDTESTC(FDB_PROTECT) == 0) 1240 write = 1; 1241 else { 1242 error = EPERM; 1243 goto done; 1244 } 1245 1246 /* 1247 * figure trk given blkno 1248 */ 1249 trk = bp->b_blkno / sc->nsectors; 1250 1251 /* 1252 * check to see if same as currently cached track 1253 * if so we need to do no DMA read. 1254 */ 1255 if (trk == sc->cachetrk) { 1256 fddone(sc); 1257 return; 1258 } 1259 1260 /* 1261 * if we will be overwriting the entire cache, don't bother to 1262 * fetch it. 1263 */ 1264 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1265 bp->b_blkno % sc->nsectors == 0) { 1266 if (sc->flags & FDF_DIRTY) 1267 sc->flags |= FDF_JUSTFLUSH; 1268 else { 1269 sc->cachetrk = trk; 1270 fddone(sc); 1271 return; 1272 } 1273 } 1274 1275 /* 1276 * start DMA read of `trk' 1277 */ 1278 fddmastart(sc, trk); 1279 return; 1280 done: 1281 bp->b_error = error; 1282 fddone(sc); 1283 } 1284 1285 /* 1286 * continue a started operation on next track. always begin at 1287 * sector 0 on the next track. 1288 */ 1289 void 1290 fdcont(struct fd_softc *sc) 1291 { 1292 struct buf *dp, *bp; 1293 int trk, write; 1294 1295 dp = &sc->curbuf; 1296 bp = bufq_peek(sc->bufq); 1297 dp->b_data = (char*)dp->b_data + (dp->b_bcount - bp->b_resid); 1298 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1299 dp->b_bcount = bp->b_resid; 1300 1301 /* 1302 * figure trk given blkno 1303 */ 1304 trk = dp->b_blkno / sc->nsectors; 1305 #ifdef DEBUG 1306 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1307 panic("fdcont: confused"); 1308 #endif 1309 if (dp->b_flags & B_READ) 1310 write = 0; 1311 else 1312 write = 1; 1313 /* 1314 * if we will be overwriting the entire cache, don't bother to 1315 * fetch it. 1316 */ 1317 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1318 if (sc->flags & FDF_DIRTY) 1319 sc->flags |= FDF_JUSTFLUSH; 1320 else { 1321 sc->cachetrk = trk; 1322 fddone(sc); 1323 return; 1324 } 1325 } 1326 /* 1327 * start DMA read of `trk' 1328 */ 1329 fddmastart(sc, trk); 1330 return; 1331 } 1332 1333 void 1334 fddmastart(struct fd_softc *sc, int trk) 1335 { 1336 int adkmask, ndmaw, write, dmatrk; 1337 1338 #ifdef FDDEBUG 1339 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1340 trk / FDNHEADS, trk % FDNHEADS); 1341 #endif 1342 /* 1343 * flush the cached track if dirty else read requested track. 1344 */ 1345 if (sc->flags & FDF_DIRTY) { 1346 fdcachetoraw(sc); 1347 ndmaw = sc->type->nwritew; 1348 dmatrk = sc->cachetrk; 1349 write = 1; 1350 } else { 1351 ndmaw = sc->type->nreadw; 1352 dmatrk = trk; 1353 write = 0; 1354 } 1355 1356 #ifdef FDDEBUG 1357 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1358 #endif 1359 sc->cachetrk = trk; 1360 fdc_indma = sc; 1361 fdsetpos(sc, dmatrk, write); 1362 1363 /* 1364 * setup dma stuff 1365 */ 1366 if (write == 0) { 1367 custom.adkcon = ADKF_MSBSYNC; 1368 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1369 custom.dsksync = FDMFMSYNC; 1370 } else { 1371 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1372 ADKF_MSBSYNC; 1373 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1374 if (dmatrk >= sc->type->precomp[0]) 1375 adkmask |= ADKF_PRECOMP0; 1376 if (dmatrk >= sc->type->precomp[1]) 1377 adkmask |= ADKF_PRECOMP1; 1378 custom.adkcon = adkmask; 1379 } 1380 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1381 1382 /* 1383 * If writing an MSDOS track, activate disk index pulse 1384 * interrupt, DMA will be started in the intr routine fdidxintr() 1385 * Otherwise, start the DMA here. 1386 */ 1387 if (write && sc->openpart == FDMSDOSPART) { 1388 fdc_dmalen = ndmaw; 1389 fdc_dmawrite = write; 1390 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1391 } else { 1392 FDDMASTART(ndmaw, write); 1393 fdc_dmalen = 0; 1394 } 1395 1396 #ifdef FDDEBUG 1397 printf(" DMA started\n"); 1398 #endif 1399 } 1400 1401 /* 1402 * recalibrate the drive 1403 */ 1404 void 1405 fdcalibrate(void *arg) 1406 { 1407 struct fd_softc *sc; 1408 static int loopcnt; 1409 1410 sc = arg; 1411 1412 if (loopcnt == 0) { 1413 /* 1414 * seek cyl 0 1415 */ 1416 fdc_indma = sc; 1417 sc->stepdelay += 900; 1418 if (sc->cachetrk > 1) 1419 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1420 sc->stepdelay -= 900; 1421 } 1422 if (loopcnt++ & 1) 1423 fdsetpos(sc, sc->cachetrk, 0); 1424 else 1425 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1426 /* 1427 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and DMA 1428 */ 1429 if (loopcnt < 8) 1430 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1431 else { 1432 loopcnt = 0; 1433 fdc_indma = NULL; 1434 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1435 fddmastart(sc, sc->cachetrk); 1436 } 1437 } 1438 1439 void 1440 fddmadone(struct fd_softc *sc, int timeo) 1441 { 1442 #ifdef FDDEBUG 1443 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1444 #endif 1445 fdc_indma = NULL; 1446 callout_stop(&sc->motor_ch); 1447 FDDMASTOP; 1448 1449 /* 1450 * guarantee the drive has been at current head and cyl 1451 * for at least FDWRITEDELAY after a write. 1452 */ 1453 if (sc->flags & FDF_WRITEWAIT) { 1454 delay(FDWRITEDELAY); 1455 sc->flags &= ~FDF_WRITEWAIT; 1456 } 1457 1458 if ((sc->flags & FDF_MOTOROFF) == 0) { 1459 /* 1460 * motor runs for 1.5 seconds after last DMA 1461 */ 1462 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1463 } 1464 if (sc->flags & FDF_DIRTY) { 1465 /* 1466 * if buffer dirty, the last DMA cleaned it 1467 */ 1468 sc->flags &= ~FDF_DIRTY; 1469 if (timeo) 1470 printf("%s: write of track cache timed out.\n", 1471 sc->sc_dv.dv_xname); 1472 if (sc->flags & FDF_JUSTFLUSH) { 1473 sc->flags &= ~FDF_JUSTFLUSH; 1474 /* 1475 * we are done DMA'ing 1476 */ 1477 fddone(sc); 1478 return; 1479 } 1480 /* 1481 * load the cache 1482 */ 1483 fddmastart(sc, sc->cachetrk); 1484 return; 1485 } 1486 #ifdef FDDEBUG 1487 else if (sc->flags & FDF_MOTOROFF) 1488 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1489 #endif 1490 1491 /* 1492 * cache loaded decode it into cache buffer 1493 */ 1494 if (timeo == 0 && fdrawtocache(sc) == 0) 1495 sc->retried = 0; 1496 else { 1497 #ifdef FDDEBUG 1498 if (timeo) 1499 printf("%s: fddmadone: cache load timed out.\n", 1500 sc->sc_dv.dv_xname); 1501 #endif 1502 if (sc->retried >= sc->retries) { 1503 sc->retried = 0; 1504 sc->cachetrk = -1; 1505 } else { 1506 sc->retried++; 1507 /* 1508 * this will be restarted at end of calibrate loop. 1509 */ 1510 callout_stop(&sc->motor_ch); 1511 fdcalibrate(sc); 1512 return; 1513 } 1514 } 1515 fddone(sc); 1516 } 1517 1518 void 1519 fddone(struct fd_softc *sc) 1520 { 1521 struct buf *dp, *bp; 1522 char *data; 1523 int sz; 1524 1525 #ifdef FDDEBUG 1526 printf("fddone: unit %d\n", sc->hwunit); 1527 #endif 1528 /* 1529 * check to see if unit is just flushing the cache, 1530 * that is we have no io queued. 1531 */ 1532 if (sc->flags & FDF_MOTOROFF) 1533 goto nobuf; 1534 1535 dp = &sc->curbuf; 1536 if ((bp = bufq_peek(sc->bufq)) == NULL) 1537 panic ("fddone"); 1538 /* 1539 * check for an error that may have occurred 1540 * while getting the track. 1541 */ 1542 if (sc->cachetrk == -1) { 1543 sc->retried = 0; 1544 bp->b_error = EIO; 1545 } else if (bp->b_error == 0) { 1546 data = sc->cachep; 1547 /* 1548 * get offset of data in track cache and limit 1549 * the copy size to not exceed the cache's end. 1550 */ 1551 data += (dp->b_blkno % sc->nsectors) * FDSECSIZE; 1552 sz = sc->nsectors - dp->b_blkno % sc->nsectors; 1553 sz *= FDSECSIZE; 1554 sz = min(dp->b_bcount, sz); 1555 if (bp->b_flags & B_READ) 1556 memcpy(dp->b_data, data, sz); 1557 else { 1558 memcpy(data, dp->b_data, sz); 1559 sc->flags |= FDF_DIRTY; 1560 } 1561 bp->b_resid = dp->b_bcount - sz; 1562 if (bp->b_resid == 0) { 1563 bp->b_error = 0; 1564 } else { 1565 /* 1566 * not done yet need to read next track 1567 */ 1568 fdcont(sc); 1569 return; 1570 } 1571 } 1572 /* 1573 * remove from queue. 1574 */ 1575 (void)bufq_get(sc->bufq); 1576 1577 disk_unbusy(&sc->dkdev, (bp->b_bcount - bp->b_resid), 1578 (bp->b_flags & B_READ)); 1579 1580 biodone(bp); 1581 nobuf: 1582 fdfindwork(device_unit(&sc->sc_dv)); 1583 } 1584 1585 void 1586 fdfindwork(int unit) 1587 { 1588 struct fd_softc *ssc, *sc; 1589 int i, last; 1590 1591 /* 1592 * first see if we have any fdopen()'s waiting 1593 */ 1594 if (fdc_wantwakeup) { 1595 wakeup(fdopen); 1596 fdc_wantwakeup--; 1597 return; 1598 } 1599 1600 /* 1601 * start next available unit, linear search from the next unit 1602 * wrapping and finally this unit. 1603 */ 1604 last = 0; 1605 ssc = NULL; 1606 for (i = unit + 1; last == 0; i++) { 1607 if (i == unit) 1608 last = 1; 1609 if (i >= fd_cd.cd_ndevs) { 1610 i = -1; 1611 continue; 1612 } 1613 if ((sc = device_lookup_private(&fd_cd, i)) == NULL) 1614 continue; 1615 1616 /* 1617 * if unit has requested to be turned off 1618 * and it has no buf's queued do it now 1619 */ 1620 if (sc->flags & FDF_MOTOROFF) { 1621 if (bufq_peek(sc->bufq) == NULL) 1622 fdmotoroff(sc); 1623 else { 1624 /* 1625 * we gained a buf request while 1626 * we waited, forget the motoroff 1627 */ 1628 sc->flags &= ~FDF_MOTOROFF; 1629 } 1630 /* 1631 * if we now have DMA unit must have needed 1632 * flushing, quit 1633 */ 1634 if (fdc_indma) 1635 return; 1636 } 1637 /* 1638 * if we have no start unit and the current unit has 1639 * io waiting choose this unit to start. 1640 */ 1641 if (ssc == NULL && bufq_peek(sc->bufq) != NULL) 1642 ssc = sc; 1643 } 1644 if (ssc) 1645 fdstart(ssc); 1646 } 1647 1648 /* 1649 * min byte count to whats left of the track in question 1650 */ 1651 void 1652 fdminphys(struct buf *bp) 1653 { 1654 struct fd_softc *sc; 1655 int trk, sec, toff, tsz; 1656 1657 if ((sc = getsoftc(fd_cd, FDUNIT(bp->b_dev))) == NULL) 1658 panic("fdminphys: couldn't get softc"); 1659 1660 trk = bp->b_blkno / sc->nsectors; 1661 sec = bp->b_blkno % sc->nsectors; 1662 1663 toff = sec * FDSECSIZE; 1664 tsz = sc->nsectors * FDSECSIZE; 1665 #ifdef FDDEBUG 1666 printf("fdminphys: before %ld", bp->b_bcount); 1667 #endif 1668 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1669 #ifdef FDDEBUG 1670 printf(" after %ld\n", bp->b_bcount); 1671 #endif 1672 minphys(bp); 1673 } 1674 1675 /* 1676 * encode the track cache into raw MFM ready for DMA 1677 * when we go to multiple disk formats, this will call type dependent 1678 * functions 1679 */ 1680 void fdcachetoraw(struct fd_softc *sc) 1681 { 1682 if (sc->openpart == FDMSDOSPART) 1683 mscachetoraw(sc); 1684 else 1685 amcachetoraw(sc); 1686 } 1687 1688 /* 1689 * decode raw MFM from DMA into units track cache. 1690 * when we go to multiple disk formats, this will call type dependent 1691 * functions 1692 */ 1693 int 1694 fdrawtocache(struct fd_softc *sc) 1695 { 1696 1697 if (sc->openpart == FDMSDOSPART) 1698 return(msrawtocache(sc)); 1699 else 1700 return(amrawtocache(sc)); 1701 } 1702 1703 void 1704 amcachetoraw(struct fd_softc *sc) 1705 { 1706 static u_long mfmnull[4]; 1707 u_long *rp, *crp, *dp, hcksum, dcksum, info, zero; 1708 int sec, i; 1709 1710 rp = fdc_dmap; 1711 1712 /* 1713 * not yet one sector (- 1 long) gap. 1714 * for now use previous drivers values 1715 */ 1716 for (i = 0; i < sc->type->gap; i++) 1717 *rp++ = 0xaaaaaaaa; 1718 /* 1719 * process sectors 1720 */ 1721 dp = sc->cachep; 1722 zero = 0; 1723 info = 0xff000000 | (sc->cachetrk << 16) | sc->nsectors; 1724 for (sec = 0; sec < sc->nsectors; sec++, info += (1 << 8) - 1) { 1725 hcksum = dcksum = 0; 1726 /* 1727 * sector format 1728 * offset description 1729 *----------------------------------- 1730 * 0 null 1731 * 1 sync 1732 * oddbits evenbits 1733 *---------------------- 1734 * 2 3 [0xff]b [trk]b [sec]b [togap]b 1735 * 4-7 8-11 null 1736 * 12 13 header cksum [2-11] 1737 * 14 15 data cksum [16-271] 1738 * 16-143 144-271 data 1739 */ 1740 *rp = 0xaaaaaaaa; 1741 if (*(rp - 1) & 0x1) 1742 *rp &= 0x7fffffff; /* clock bit correction */ 1743 rp++; 1744 *rp++ = (FDMFMSYNC << 16) | FDMFMSYNC; 1745 rp = mfmblkencode(&info, rp, &hcksum, 1); 1746 rp = mfmblkencode(mfmnull, rp, &hcksum, 4); 1747 rp = mfmblkencode(&hcksum, rp, NULL, 1); 1748 1749 crp = rp; 1750 rp = mfmblkencode(dp, rp + 2, &dcksum, FDSECLWORDS); 1751 dp += FDSECLWORDS; 1752 crp = mfmblkencode(&dcksum, crp, NULL, 1); 1753 if (*(crp - 1) & 0x1) 1754 *crp &= 0x7fffffff; /* clock bit correction */ 1755 else if ((*crp & 0x40000000) == 0) 1756 *crp |= 0x80000000; 1757 } 1758 *rp = 0xaaa80000; 1759 if (*(rp - 1) & 0x1) 1760 *rp &= 0x7fffffff; 1761 } 1762 1763 u_long * 1764 fdfindsync(u_long *rp, u_long *ep) 1765 { 1766 u_short *sp; 1767 1768 sp = (u_short *)rp; 1769 while ((u_long *)sp < ep && *sp != FDMFMSYNC) 1770 sp++; 1771 while ((u_long *)sp < ep && *sp == FDMFMSYNC) 1772 sp++; 1773 if ((u_long *)sp < ep) 1774 return((u_long *)sp); 1775 return(NULL); 1776 } 1777 1778 int 1779 amrawtocache(struct fd_softc *sc) 1780 { 1781 u_long mfmnull[4]; 1782 u_long *dp, *rp, *erp, *crp, *srp, hcksum, dcksum, info, cktmp; 1783 int cnt, doagain; 1784 1785 doagain = 1; 1786 srp = rp = fdc_dmap; 1787 erp = (u_long *)((u_short *)rp + sc->type->nreadw); 1788 cnt = 0; 1789 again: 1790 if (doagain == 0 || (rp = srp = fdfindsync(srp, erp)) == NULL) { 1791 #ifdef DIAGNOSTIC 1792 printf("%s: corrupted track (%d) data.\n", 1793 sc->sc_dv.dv_xname, sc->cachetrk); 1794 #endif 1795 return(-1); 1796 } 1797 1798 /* 1799 * process sectors 1800 */ 1801 for (; cnt < sc->nsectors; cnt++) { 1802 hcksum = dcksum = 0; 1803 rp = mfmblkdecode(rp, &info, &hcksum, 1); 1804 rp = mfmblkdecode(rp, mfmnull, &hcksum, 4); 1805 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1806 if (cktmp != hcksum) { 1807 #ifdef FDDEBUG 1808 printf(" info 0x%lx hchksum 0x%lx trkhcksum 0x%lx\n", 1809 info, hcksum, cktmp); 1810 #endif 1811 goto again; 1812 } 1813 if (((info >> 16) & 0xff) != sc->cachetrk) { 1814 #ifdef DEBUG 1815 printf("%s: incorrect track found: 0x%lx %d\n", 1816 sc->sc_dv.dv_xname, info, sc->cachetrk); 1817 #endif 1818 goto again; 1819 } 1820 #ifdef FDDEBUG 1821 printf(" info 0x%lx\n", info); 1822 #endif 1823 1824 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1825 dp = sc->cachep; 1826 dp += FDSECLWORDS * ((info >> 8) & 0xff); 1827 crp = mfmblkdecode(rp, dp, &dcksum, FDSECLWORDS); 1828 if (cktmp != dcksum) { 1829 #ifdef FDDEBUG 1830 printf(" info 0x%lx dchksum 0x%lx trkdcksum 0x%lx\n", 1831 info, dcksum, cktmp); 1832 #endif 1833 goto again; 1834 } 1835 1836 /* 1837 * if we are at gap then we can no longer be sure 1838 * of correct sync marks 1839 */ 1840 if ((info && 0xff) == 1) 1841 doagain = 1; 1842 else 1843 doagain = 0; 1844 srp = rp = fdfindsync(crp, erp); 1845 } 1846 return(0); 1847 } 1848 1849 void 1850 mscachetoraw(struct fd_softc *sc) 1851 { 1852 u_short *rp, *erp, crc; 1853 u_char *cp, tb[5]; 1854 int sec, i; 1855 1856 rp = (u_short *)fdc_dmap; 1857 erp = rp + sc->type->nwritew; 1858 cp = sc->cachep; 1859 1860 /* 1861 * initial track filler (828 * GAP1) 1862 */ 1863 for (i = 0; i < sc->type->gap; i++) { 1864 *rp++ = FDMFMGAP1; 1865 *rp++ = FDMFMGAP1; 1866 } 1867 1868 for (sec = 0; sec < sc->nsectors; sec++) { 1869 1870 /* 1871 * leading sector gap 1872 * (12 * GAP2) + (3 * SYNC) 1873 */ 1874 for (i = 0; i < 12; i++) 1875 *rp++ = FDMFMGAP2; 1876 *rp++ = FDMFMSYNC; 1877 *rp++ = FDMFMSYNC; 1878 *rp++ = FDMFMSYNC; 1879 1880 /* 1881 * sector information 1882 * (ID) + track + side + sector + sector size + CRC16 1883 */ 1884 *rp++ = FDMFMID; 1885 tb[0] = sc->cachetrk / FDNHEADS; 1886 tb[1] = sc->cachetrk % FDNHEADS; 1887 tb[2] = sec + 1; 1888 i = sc->bytespersec; 1889 tb[3] = i < 256 ? 0 : (i < 512 ? 1 : (i < 1024 ? 2 : 3)); 1890 rp = msblkencode(rp, tb, 4, &crc); 1891 tb[0] = crc >> 8; 1892 tb[1] = crc & 0xff; 1893 tb[2] = 0x4e; /* GAP1 decoded */ 1894 rp = msblkencode(rp, tb, 3, 0); 1895 1896 /* 1897 * sector info/data gap 1898 * (22 * GAP1) + (12 * GAP2) + (3 * SYNC) 1899 */ 1900 for (i = 0; i < 21; i++) 1901 *rp++ = FDMFMGAP1; 1902 for (i = 0; i < 12; i++) 1903 *rp++ = FDMFMGAP2; 1904 *rp++ = FDMFMSYNC; 1905 *rp++ = FDMFMSYNC; 1906 *rp++ = FDMFMSYNC; 1907 1908 /* 1909 * sector data 1910 * (DATA) + ...data... + CRC16 1911 */ 1912 *rp++ = FDMFMDATA; 1913 rp = msblkencode(rp, cp, sc->bytespersec, &crc); 1914 cp += sc->bytespersec; 1915 tb[0] = crc >> 8; 1916 tb[1] = crc & 0xff; 1917 tb[2] = 0x4e; /* GAP3 decoded */ 1918 rp = msblkencode(rp, tb, 3, 0); 1919 1920 /* 1921 * trailing sector gap 1922 * (80 * GAP3) 1923 */ 1924 for (i = 0; i < 79; i++) 1925 *rp++ = FDMFMGAP3; 1926 } 1927 1928 /* 1929 * fill rest of track with GAP3 1930 */ 1931 while (rp != erp) 1932 *rp++ = FDMFMGAP3; 1933 1934 } 1935 1936 int 1937 msrawtocache(struct fd_softc *sc) 1938 { 1939 u_short *rp, *srp, *erp; 1940 u_char tb[5], *cp; 1941 int ct, sec, retry; 1942 1943 srp = rp = (u_short *)fdc_dmap; 1944 erp = rp + sc->type->nreadw; 1945 cp = sc->cachep; 1946 1947 for (ct = 0; ct < sc->nsectors; ct++) { 1948 retry = 1; 1949 do { 1950 /* 1951 * skip leading gap to sync 1952 */ 1953 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) { 1954 #ifdef DIAGNOSTIC 1955 printf("%s: corrupted track (%d) data.\n", 1956 sc->sc_dv.dv_xname, sc->cachetrk); 1957 #endif 1958 return(-1); 1959 } 1960 1961 /* 1962 * Grab sector info 1963 */ 1964 if (*rp++ != FDMFMID) 1965 continue; 1966 rp = msblkdecode(rp, tb, 4); 1967 #ifdef FDDEBUG 1968 printf("sector id: sector %d, track %d, side %d," 1969 "bps %d\n", tb[2], tb[0], tb[1], 128 << tb[3]); 1970 #endif 1971 if ((tb[0] * FDNHEADS + tb[1]) != sc->cachetrk || 1972 tb[2] > sc->nsectors) 1973 continue; 1974 1975 sec = tb[2]; 1976 sc->bytespersec = 128 << tb[3]; 1977 rp += 2; /* skip CRC-16 */ 1978 1979 /* 1980 * skip gap and read in data 1981 */ 1982 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) 1983 return(-1); 1984 if (*rp++ != FDMFMDATA) 1985 continue; 1986 rp = msblkdecode(rp, cp + ((sec-1) * sc->bytespersec), 1987 sc->bytespersec); 1988 rp += 2; /* skip CRC-16 */ 1989 1990 retry = 0; 1991 } while (retry); 1992 } 1993 return(0); 1994 } 1995 1996 /* 1997 * encode len longwords of `dp' data in amiga mfm block format (`rp') 1998 * this format specified that the odd bits are at current pos and even 1999 * bits at len + current pos 2000 */ 2001 u_long * 2002 mfmblkencode(u_long *dp, u_long *rp, u_long *cp, int len) 2003 { 2004 u_long *sdp, *edp, d, dtmp, correct; 2005 2006 sdp = dp; 2007 edp = dp + len; 2008 2009 if (*(rp - 1) & 0x1) 2010 correct = 1; 2011 else 2012 correct = 0; 2013 /* 2014 * do odd bits 2015 */ 2016 while (dp < edp) { 2017 d = (*dp >> 1) & 0x55555555; /* remove clock bits */ 2018 dtmp = d ^ 0x55555555; 2019 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2020 /* 2021 * correct upper clock bit if needed 2022 */ 2023 if (correct) 2024 d &= 0x7fffffff; 2025 if (d & 0x1) 2026 correct = 1; 2027 else 2028 correct = 0; 2029 /* 2030 * do checksums and store in raw buffer 2031 */ 2032 if (cp) 2033 *cp ^= d; 2034 *rp++ = d; 2035 dp++; 2036 } 2037 /* 2038 * do even bits 2039 */ 2040 dp = sdp; 2041 while (dp < edp) { 2042 d = *dp & 0x55555555; /* remove clock bits */ 2043 dtmp = d ^ 0x55555555; 2044 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2045 /* 2046 * correct upper clock bit if needed 2047 */ 2048 if (correct) 2049 d &= 0x7fffffff; 2050 if (d & 0x1) 2051 correct = 1; 2052 else 2053 correct = 0; 2054 /* 2055 * do checksums and store in raw buffer 2056 */ 2057 if (cp) 2058 *cp ^= d; 2059 *rp++ = d; 2060 dp++; 2061 } 2062 if (cp) 2063 *cp &= 0x55555555; 2064 return(rp); 2065 } 2066 2067 /* 2068 * decode len longwords of `dp' data in amiga mfm block format (`rp') 2069 * this format specified that the odd bits are at current pos and even 2070 * bits at len + current pos 2071 */ 2072 u_long * 2073 mfmblkdecode(u_long *rp, u_long *dp, u_long *cp, int len) 2074 { 2075 u_long o, e; 2076 int cnt; 2077 2078 cnt = len; 2079 while (cnt--) { 2080 o = *rp; 2081 e = *(rp + len); 2082 if (cp) { 2083 *cp ^= o; 2084 *cp ^= e; 2085 } 2086 o &= 0x55555555; 2087 e &= 0x55555555; 2088 *dp++ = (o << 1) | e; 2089 rp++; 2090 } 2091 if (cp) 2092 *cp &= 0x55555555; 2093 return(rp + len); 2094 } 2095 2096 /* 2097 * decode len words in standard MFM format to len bytes 2098 * of data. 2099 */ 2100 u_short * 2101 msblkdecode(u_short *rp, u_char *cp, int len) 2102 { 2103 while (len--) { 2104 *cp++ = msdecode[*rp & 0x7f] | 2105 (msdecode[(*rp >> 8) & 0x7f] << 4); 2106 rp++; 2107 } 2108 2109 return(rp); 2110 } 2111 2112 /* 2113 * encode len bytes of data into len words in standard MFM format. 2114 * If a pointer is supplied for crc, calculate the CRC-16 of the data 2115 * as well. 2116 */ 2117 u_short * 2118 msblkencode(u_short *rp, u_char *cp, int len, u_short *crc) 2119 { 2120 u_short td; 2121 u_short mycrc; 2122 2123 /* preload crc for header (4 bytes) 2124 * or data (anything else) 2125 */ 2126 mycrc = (len == 4) ? 0xb230 : 0xe295; 2127 2128 while (len--) { 2129 td = (msencode[*cp >> 4] << 8) | msencode[*cp & 0x0f]; 2130 2131 /* Check for zeros in top bit of encode and bottom 2132 * bit of previous encode. if so, slap a one in betweem 2133 * them. 2134 */ 2135 if ((td & 0x140) == 0) 2136 td |= 0x80; 2137 if ((td & 0x4000) == 0 && (rp[-1] & 1) == 0) 2138 td |= 0x8000; 2139 2140 *rp++ = td; 2141 2142 /* 2143 * calc crc if requested 2144 */ 2145 if (crc) 2146 mycrc = (mycrc << 8) ^ mscrctab[*cp ^ (mycrc >> 8)]; 2147 2148 cp++; 2149 } 2150 2151 if (crc) 2152 *crc = mycrc; 2153 2154 return(rp); 2155 } 2156
Indexes created Thu Oct 02 14:10:14 GMT 2025