fd.c revision 1.89.2.1
1 /* $NetBSD: fd.c,v 1.89.2.1 2014/08/10 06:53:49 tls 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 1.89.2.1 2014/08/10 06:53:49 tls 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 device_t sc_dev; /* 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(device_t, cfdata_t, void *); 193 void fdcattach(device_t, device_t, void *); 194 int fdcprint(void *, const char *); 195 int fdmatch(device_t, cfdata_t, void *); 196 void fdattach(device_t, device_t, 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_NEW(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 .d_open = fdopen, 258 .d_close = fdclose, 259 .d_strategy = fdstrategy, 260 .d_ioctl = fdioctl, 261 .d_dump = nodump, 262 .d_psize = nosize, 263 .d_discard = nodiscard, 264 .d_flag = D_DISK 265 }; 266 267 const struct cdevsw fd_cdevsw = { 268 .d_open = fdopen, 269 .d_close = fdclose, 270 .d_read = fdread, 271 .d_write = fdwrite, 272 .d_ioctl = fdioctl, 273 .d_stop = nostop, 274 .d_tty = notty, 275 .d_poll = nopoll, 276 .d_mmap = nommap, 277 .d_kqfilter = nokqfilter, 278 .d_discard = nodiscard, 279 .d_flag = D_DISK 280 }; 281 282 struct dkdriver fddkdriver = { fdstrategy }; 283 284 CFATTACH_DECL_NEW(fdc, 0, 285 fdcmatch, fdcattach, NULL, NULL); 286 287 /* 288 * all hw access through macros, this helps to hide the active low 289 * properties 290 */ 291 292 #define FDUNITMASK(unit) (1 << (3 + (unit))) 293 294 /* 295 * select units using mask 296 */ 297 #define FDSELECT(um) do { ciab.prb &= ~(um); } while (0) 298 299 /* 300 * deselect units using mask 301 */ 302 #define FDDESELECT(um) do { ciab.prb |= (um); delay(1); } while (0) 303 304 /* 305 * test hw condition bits 306 */ 307 #define FDTESTC(bit) ((ciaa.pra & (1 << (bit))) == 0) 308 309 /* 310 * set motor for select units, true motor on else off 311 */ 312 #define FDSETMOTOR(on) do { \ 313 if (on) ciab.prb &= ~CIAB_PRB_MTR; else ciab.prb |= CIAB_PRB_MTR; \ 314 } while (0) 315 316 /* 317 * set head for select units 318 */ 319 #define FDSETHEAD(head) do { \ 320 if (head) ciab.prb &= ~CIAB_PRB_SIDE; else ciab.prb |= CIAB_PRB_SIDE; \ 321 delay(1); } while (0) 322 323 /* 324 * select direction, true towards spindle else outwards 325 */ 326 #define FDSETDIR(in) do { \ 327 if (in) ciab.prb &= ~CIAB_PRB_DIR; else ciab.prb |= CIAB_PRB_DIR; \ 328 delay(1); } while (0) 329 330 /* 331 * step the selected units 332 */ 333 #define FDSTEP do { \ 334 ciab.prb &= ~CIAB_PRB_STEP; ciab.prb |= CIAB_PRB_STEP; \ 335 } while (0) 336 337 #define FDDMASTART(len, towrite) do { \ 338 int dmasz = (len) | ((towrite) ? DISKLEN_WRITE : 0) | DISKLEN_DMAEN; \ 339 custom.dsklen = dmasz; custom.dsklen = dmasz; } while (0) 340 341 #define FDDMASTOP do { custom.dsklen = 0; } while (0) 342 343 344 int 345 fdcmatch(device_t parent, cfdata_t cf, void *aux) 346 { 347 static int fdc_matched = 0; 348 349 /* Allow only once instance. */ 350 if (matchname("fdc", aux) == 0 || fdc_matched) 351 return(0); 352 if ((fdc_dmap = alloc_chipmem(DMABUFSZ)) == NULL) { 353 printf("fdc: unable to allocate DMA buffer\n"); 354 return(0); 355 } 356 357 fdc_matched = 1; 358 return(1); 359 } 360 361 void 362 fdcattach(device_t parent, device_t self, void *aux) 363 { 364 struct fdcargs args; 365 366 printf(": dmabuf pa 0x%x", (unsigned)kvtop(fdc_dmap)); 367 printf(": dmabuf ka %p\n", fdc_dmap); 368 args.unit = 0; 369 args.type = fdcgetfdtype(args.unit); 370 371 fdc_side = -1; 372 config_found(self, &args, fdcprint); 373 for (args.unit++; args.unit < FDMAXUNITS; args.unit++) { 374 if ((args.type = fdcgetfdtype(args.unit)) == NULL) 375 continue; 376 config_found(self, &args, fdcprint); 377 } 378 } 379 380 int 381 fdcprint(void *aux, const char *pnp) 382 { 383 struct fdcargs *fcp; 384 385 fcp = aux; 386 if (pnp) 387 aprint_normal("fd%d at %s unit %d:", fcp->unit, pnp, 388 fcp->type->driveid); 389 return(UNCONF); 390 } 391 392 /*ARGSUSED*/ 393 int 394 fdmatch(device_t parent, cfdata_t cf, void *aux) 395 { 396 struct fdcargs *fdap; 397 398 fdap = aux; 399 if (cf->cf_loc[FDCCF_UNIT] == fdap->unit || 400 cf->cf_loc[FDCCF_UNIT] == FDCCF_UNIT_DEFAULT) 401 return(1); 402 403 return(0); 404 } 405 406 void 407 fdattach(device_t parent, device_t self, void *aux) 408 { 409 struct fdcargs *ap; 410 struct fd_softc *sc; 411 int i; 412 413 ap = aux; 414 sc = device_private(self); 415 sc->sc_dev = self; 416 417 bufq_alloc(&sc->bufq, "disksort", BUFQ_SORT_CYLINDER); 418 callout_init(&sc->calibrate_ch, 0); 419 callout_init(&sc->motor_ch, 0); 420 421 sc->curcyl = sc->cachetrk = -1; 422 sc->openpart = -1; 423 sc->type = ap->type; 424 sc->hwunit = ap->unit; 425 sc->unitmask = 1 << (3 + ap->unit); 426 sc->retries = FDRETRIES; 427 sc->stepdelay = FDSTEPDELAY; 428 sc->bytespersec = 512; 429 printf(" unit %d: %s %d cyl, %d head, %d sec [%d sec], 512 bytes/sec\n", 430 sc->hwunit, sc->type->desc, sc->type->ncylinders, FDNHEADS, 431 sc->type->amiga_nsectors, sc->type->msdos_nsectors); 432 433 /* 434 * Initialize and attach the disk structure. 435 */ 436 disk_init(&sc->dkdev, device_xname(sc->sc_dev), &fddkdriver); 437 disk_attach(&sc->dkdev); 438 439 /* 440 * calibrate the drive 441 */ 442 fdsetpos(sc, 0, 0); 443 fdsetpos(sc, sc->type->ncylinders, 0); 444 fdsetpos(sc, 0, 0); 445 fdmotoroff(sc); 446 447 /* 448 * precalc msdos MFM and CRC 449 */ 450 for (i = 0; i < 128; i++) 451 msdecode[i] = 0xff; 452 for (i = 0; i < 16; i++) 453 msdecode[msencode[i]] = i; 454 for (i = 0; i < 256; i++) { 455 mscrctab[i] = (0x1021 * (i & 0xf0)) ^ (0x1021 * (i & 0x0f)) ^ 456 (0x1021 * (i >> 4)); 457 } 458 459 /* 460 * enable disk related interrupts 461 */ 462 custom.dmacon = DMAF_SETCLR | DMAF_MASTER | DMAF_DISK; 463 custom.intena = INTF_SETCLR | INTF_DSKBLK; 464 ciab.icr = CIA_ICR_FLG; 465 } 466 467 /*ARGSUSED*/ 468 int 469 fdopen(dev_t dev, int flags, int devtype, struct lwp *l) 470 { 471 struct fd_softc *sc; 472 int wasopen, fwork, error, s; 473 474 error = 0; 475 476 if (FDPART(dev) >= FDMAXPARTS) 477 return(ENXIO); 478 479 if ((sc = getsoftc(fd_cd, FDUNIT(dev))) == NULL) 480 return(ENXIO); 481 if (sc->flags & FDF_NOTRACK0) 482 return(ENXIO); 483 if (sc->cachep == NULL) 484 sc->cachep = malloc(MAXTRKSZ, M_DEVBUF, M_WAITOK); 485 486 s = splbio(); 487 /* 488 * if we are sleeping in fdclose(); waiting for a chance to 489 * shut the motor off, do a sleep here also. 490 */ 491 while (sc->flags & FDF_WMOTOROFF) 492 tsleep(fdmotoroff, PRIBIO, "fdopen", 0); 493 494 fwork = 0; 495 /* 496 * if not open let user open request type, otherwise 497 * ensure they are trying to open same type. 498 */ 499 if (sc->openpart == FDPART(dev)) 500 wasopen = 1; 501 else if (sc->openpart == -1) { 502 sc->openpart = FDPART(dev); 503 wasopen = 0; 504 } else { 505 wasopen = 1; 506 error = EPERM; 507 goto done; 508 } 509 510 /* 511 * wait for current io to complete if any 512 */ 513 if (fdc_indma) { 514 fwork = 1; 515 fdc_wantwakeup++; 516 tsleep(fdopen, PRIBIO, "fdopen", 0); 517 } 518 if ((error = fdloaddisk(sc)) != 0) 519 goto done; 520 if ((error = fdgetdisklabel(sc, dev)) != 0) 521 goto done; 522 #ifdef FDDEBUG 523 printf(" open successful\n"); 524 #endif 525 done: 526 /* 527 * if we requested that fddone()->fdfindwork() wake us, allow it to 528 * complete its job now 529 */ 530 if (fwork) 531 fdfindwork(FDUNIT(dev)); 532 splx(s); 533 534 /* 535 * if we were not open and we marked us so reverse that. 536 */ 537 if (error && wasopen == 0) 538 sc->openpart = -1; 539 return(error); 540 } 541 542 /*ARGSUSED*/ 543 int 544 fdclose(dev_t dev, int flags, int devtype, struct lwp *l) 545 { 546 struct fd_softc *sc; 547 int s; 548 549 #ifdef FDDEBUG 550 printf("fdclose()\n"); 551 #endif 552 sc = getsoftc(fd_cd, FDUNIT(dev)); 553 s = splbio(); 554 if (sc->flags & FDF_MOTORON) { 555 sc->flags |= FDF_WMOTOROFF; 556 tsleep(fdmotoroff, PRIBIO, "fdclose", 0); 557 sc->flags &= ~FDF_WMOTOROFF; 558 wakeup(fdmotoroff); 559 } 560 sc->openpart = -1; 561 splx(s); 562 return(0); 563 } 564 565 int 566 fdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l) 567 { 568 struct fd_softc *sc; 569 int error, wlab; 570 571 sc = getsoftc(fd_cd, FDUNIT(dev)); 572 573 if ((sc->flags & FDF_HAVELABEL) == 0) 574 return(EBADF); 575 576 switch (cmd) { 577 case DIOCSBAD: 578 return(EINVAL); 579 case DIOCSRETRIES: 580 if (*(int *)addr < 0) 581 return(EINVAL); 582 sc->retries = *(int *)addr; 583 return(0); 584 case DIOCSSTEP: 585 if (*(int *)addr < FDSTEPDELAY) 586 return(EINVAL); 587 sc->dkdev.dk_label->d_trkseek = sc->stepdelay = *(int *)addr; 588 return(0); 589 case DIOCGDINFO: 590 *(struct disklabel *)addr = *(sc->dkdev.dk_label); 591 return(0); 592 case DIOCGPART: 593 ((struct partinfo *)addr)->disklab = sc->dkdev.dk_label; 594 ((struct partinfo *)addr)->part = 595 &sc->dkdev.dk_label->d_partitions[FDPART(dev)]; 596 return(0); 597 case DIOCSDINFO: 598 if ((flag & FWRITE) == 0) 599 return(EBADF); 600 return(fdsetdisklabel(sc, (struct disklabel *)addr)); 601 case DIOCWDINFO: 602 if ((flag & FWRITE) == 0) 603 return(EBADF); 604 if ((error = fdsetdisklabel(sc, (struct disklabel *)addr)) != 0) 605 return(error); 606 wlab = sc->wlabel; 607 sc->wlabel = 1; 608 error = fdputdisklabel(sc, dev); 609 sc->wlabel = wlab; 610 return(error); 611 case DIOCWLABEL: 612 if ((flag & FWRITE) == 0) 613 return(EBADF); 614 sc->wlabel = *(int *)addr; 615 return(0); 616 case DIOCGDEFLABEL: 617 fdgetdefaultlabel(sc, (struct disklabel *)addr, FDPART(dev)); 618 return(0); 619 default: 620 return(ENOTTY); 621 } 622 } 623 624 int 625 fdread(dev_t dev, struct uio *uio, int flags) 626 { 627 return (physio(fdstrategy, NULL, dev, B_READ, fdminphys, uio)); 628 } 629 630 int 631 fdwrite(dev_t dev, struct uio *uio, int flags) 632 { 633 return (physio(fdstrategy, NULL, dev, B_WRITE, fdminphys, uio)); 634 } 635 636 637 void 638 fdintr(int flag) 639 { 640 int s; 641 642 s = splbio(); 643 if (fdc_indma) 644 fddmadone(fdc_indma, 0); 645 splx(s); 646 } 647 648 void 649 fdidxintr(void) 650 { 651 if (fdc_indma && fdc_dmalen) { 652 /* 653 * turn off intr and start actual dma 654 */ 655 ciab.icr = CIA_ICR_FLG; 656 FDDMASTART(fdc_dmalen, fdc_dmawrite); 657 fdc_dmalen = 0; 658 } 659 } 660 661 void 662 fdstrategy(struct buf *bp) 663 { 664 struct fd_softc *sc; 665 int unit, s; 666 667 unit = FDUNIT(bp->b_dev); 668 sc = getsoftc(fd_cd, unit); 669 670 #ifdef FDDEBUG 671 printf("fdstrategy: %p\n", bp); 672 #endif 673 /* 674 * check for valid partition and bounds 675 */ 676 if ((sc->flags & FDF_HAVELABEL) == 0) { 677 bp->b_error = EIO; 678 goto done; 679 } 680 if (bounds_check_with_label(&sc->dkdev, bp, sc->wlabel) <= 0) 681 goto done; 682 683 /* 684 * trans count of zero or bounds check indicates io is done 685 * we are done. 686 */ 687 if (bp->b_bcount == 0) 688 goto done; 689 690 bp->b_rawblkno = bp->b_blkno; 691 692 /* 693 * queue the buf and kick the low level code 694 */ 695 s = splbio(); 696 bufq_put(sc->bufq, bp); 697 fdstart(sc); 698 splx(s); 699 return; 700 done: 701 bp->b_resid = bp->b_bcount; 702 biodone(bp); 703 } 704 705 /* 706 * make sure disk is loaded and label is up-to-date. 707 */ 708 int 709 fdloaddisk(struct fd_softc *sc) 710 { 711 /* 712 * if diskchange is low step drive to 0 then up one then to zero. 713 */ 714 fdselunit(sc); /* make sure the unit is selected */ 715 if (FDTESTC(FDB_CHANGED)) { 716 fdsetpos(sc, 0, 0); 717 sc->cachetrk = -1; /* invalidate the cache */ 718 sc->flags &= ~FDF_HAVELABEL; 719 fdsetpos(sc, FDNHEADS, 0); 720 fdsetpos(sc, 0, 0); 721 if (FDTESTC(FDB_CHANGED)) { 722 fdmotoroff(sc); 723 FDDESELECT(sc->unitmask); 724 return(ENXIO); 725 } 726 } 727 FDDESELECT(sc->unitmask); 728 fdmotoroff(sc); 729 sc->type = fdcgetfdtype(sc->hwunit); 730 if (sc->type == NULL) 731 return(ENXIO); 732 if (sc->openpart == FDMSDOSPART) 733 sc->nsectors = sc->type->msdos_nsectors; 734 else 735 sc->nsectors = sc->type->amiga_nsectors; 736 return(0); 737 } 738 739 void 740 fdgetdefaultlabel(struct fd_softc *sc, struct disklabel *lp, int part) 741 /* (variable part) XXX ick */ 742 { 743 744 memset(lp, 0, sizeof(struct disklabel)); 745 lp->d_secsize = FDSECSIZE; 746 lp->d_ntracks = FDNHEADS; 747 lp->d_ncylinders = sc->type->ncylinders; 748 lp->d_nsectors = sc->nsectors; 749 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 750 lp->d_type = DTYPE_FLOPPY; 751 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 752 lp->d_rpm = 300; /* good guess I suppose. */ 753 lp->d_interleave = 1; /* should change when adding msdos */ 754 sc->stepdelay = lp->d_trkseek = FDSTEPDELAY; 755 lp->d_bbsize = 0; 756 lp->d_sbsize = 0; 757 lp->d_partitions[part].p_size = lp->d_secperunit; 758 lp->d_partitions[part].p_fstype = FS_UNUSED; 759 lp->d_partitions[part].p_fsize = 1024; 760 lp->d_partitions[part].p_frag = 8; 761 lp->d_partitions[part].p_cpg = 2; /* adosfs: reserved blocks */ 762 lp->d_npartitions = part + 1; 763 lp->d_magic = lp->d_magic2 = DISKMAGIC; 764 lp->d_checksum = dkcksum(lp); 765 } 766 767 /* 768 * read disk label, if present otherwise create one 769 * return a new label if raw part and none found, otherwise err. 770 */ 771 int 772 fdgetdisklabel(struct fd_softc *sc, dev_t dev) 773 { 774 struct disklabel *lp, *dlp; 775 struct cpu_disklabel *clp; 776 struct buf *bp; 777 int error, part; 778 779 if (sc->flags & FDF_HAVELABEL && 780 sc->dkdev.dk_label->d_npartitions == (FDPART(dev) + 1)) 781 return(0); 782 #ifdef FDDEBUG 783 printf("fdgetdisklabel()\n"); 784 #endif 785 part = FDPART(dev); 786 lp = sc->dkdev.dk_label; 787 clp = sc->dkdev.dk_cpulabel; 788 memset(lp, 0, sizeof(struct disklabel)); 789 memset(clp, 0, sizeof(struct cpu_disklabel)); 790 791 lp->d_secsize = FDSECSIZE; 792 lp->d_ntracks = FDNHEADS; 793 lp->d_ncylinders = sc->type->ncylinders; 794 lp->d_nsectors = sc->nsectors; 795 lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors; 796 lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders; 797 lp->d_npartitions = part + 1; 798 lp->d_partitions[part].p_size = lp->d_secperunit; 799 lp->d_partitions[part].p_fstype = FS_UNUSED; 800 lp->d_partitions[part].p_fsize = 1024; 801 lp->d_partitions[part].p_frag = 8; 802 lp->d_partitions[part].p_cpg = 2; /* for adosfs: reserved blks */ 803 804 sc->flags |= FDF_HAVELABEL; 805 806 bp = (void *)geteblk((int)lp->d_secsize); 807 bp->b_dev = dev; 808 bp->b_blkno = 0; 809 bp->b_cylinder = 0; 810 bp->b_bcount = FDSECSIZE; 811 bp->b_flags |= B_READ; 812 fdstrategy(bp); 813 if ((error = biowait(bp)) != 0) 814 goto nolabel; 815 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 816 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC || 817 dkcksum(dlp)) { 818 error = EINVAL; 819 goto nolabel; 820 } 821 memcpy(lp, dlp, sizeof(struct disklabel)); 822 if (lp->d_trkseek > FDSTEPDELAY) 823 sc->stepdelay = lp->d_trkseek; 824 brelse(bp, 0); 825 return(0); 826 nolabel: 827 fdgetdefaultlabel(sc, lp, part); 828 brelse(bp, 0); 829 return(0); 830 } 831 832 /* 833 * set the incore copy of this units disklabel 834 */ 835 int 836 fdsetdisklabel(struct fd_softc *sc, struct disklabel *lp) 837 { 838 struct disklabel *clp; 839 struct partition *pp; 840 841 /* 842 * must have at least opened raw unit to fetch the 843 * raw_part stuff. 844 */ 845 if ((sc->flags & FDF_HAVELABEL) == 0) 846 return(EINVAL); 847 clp = sc->dkdev.dk_label; 848 /* 849 * make sure things check out and we only have one valid 850 * partition 851 */ 852 #ifdef FDDEBUG 853 printf("fdsetdisklabel\n"); 854 #endif 855 if (lp->d_secsize != FDSECSIZE || 856 lp->d_nsectors != clp->d_nsectors || 857 lp->d_ntracks != FDNHEADS || 858 lp->d_ncylinders != clp->d_ncylinders || 859 lp->d_secpercyl != clp->d_secpercyl || 860 lp->d_secperunit != clp->d_secperunit || 861 lp->d_magic != DISKMAGIC || 862 lp->d_magic2 != DISKMAGIC || 863 lp->d_npartitions == 0 || 864 lp->d_npartitions > FDMAXPARTS || 865 (lp->d_partitions[0].p_offset && lp->d_partitions[1].p_offset) || 866 dkcksum(lp)) 867 return(EINVAL); 868 /* 869 * if any partitions are present make sure they 870 * represent the currently open type 871 */ 872 if ((pp = &lp->d_partitions[0])->p_size) { 873 if ((pp = &lp->d_partitions[1])->p_size == 0) 874 goto done; 875 else if (sc->openpart != 1) 876 return(EINVAL); 877 } else if (sc->openpart != 0) 878 return(EINVAL); 879 /* 880 * make sure selected partition is within bounds 881 * XXX on the second check, its to handle a bug in 882 * XXX the cluster routines as they require mutliples 883 * XXX of PAGE_SIZE currently 884 */ 885 if ((pp->p_offset + pp->p_size >= lp->d_secperunit) || 886 (pp->p_frag * pp->p_fsize % PAGE_SIZE)) 887 return(EINVAL); 888 done: 889 memcpy(clp, lp, sizeof(struct disklabel)); 890 return(0); 891 } 892 893 /* 894 * write out the incore copy of this units disklabel 895 */ 896 int 897 fdputdisklabel(struct fd_softc *sc, dev_t dev) 898 { 899 struct disklabel *lp, *dlp; 900 struct buf *bp; 901 int error; 902 903 if ((sc->flags & FDF_HAVELABEL) == 0) 904 return(EBADF); 905 #ifdef FDDEBUG 906 printf("fdputdisklabel\n"); 907 #endif 908 /* 909 * get buf and read in sector 0 910 */ 911 lp = sc->dkdev.dk_label; 912 bp = geteblk((int)lp->d_secsize); 913 bp->b_dev = FDMAKEDEV(major(dev), FDUNIT(dev), RAW_PART); 914 bp->b_blkno = 0; 915 bp->b_cylinder = 0; 916 bp->b_bcount = FDSECSIZE; 917 bp->b_flags |= B_READ; 918 fdstrategy(bp); 919 if ((error = biowait(bp)) != 0) 920 goto done; 921 /* 922 * copy disklabel to buf and write it out synchronous 923 */ 924 dlp = (struct disklabel *)((char*)bp->b_data + LABELOFFSET); 925 memcpy(dlp, lp, sizeof(struct disklabel)); 926 bp->b_blkno = 0; 927 bp->b_cylinder = 0; 928 bp->b_flags &= ~(B_READ); 929 bp->b_oflags &= ~(BO_DONE); 930 bp->b_flags |= B_WRITE; 931 fdstrategy(bp); 932 error = biowait(bp); 933 done: 934 brelse(bp, 0); 935 return(error); 936 } 937 938 /* 939 * figure out drive type or NULL if none. 940 */ 941 struct fdtype * 942 fdcgetfdtype(int unit) 943 { 944 struct fdtype *ftp; 945 u_long id, idb; 946 int cnt, umask; 947 948 id = 0; 949 umask = 1 << (3 + unit); 950 951 FDDESELECT(FDCUNITMASK); 952 953 FDSETMOTOR(1); 954 delay(1); 955 FDSELECT(umask); 956 delay(1); 957 FDDESELECT(umask); 958 959 FDSETMOTOR(0); 960 delay(1); 961 FDSELECT(umask); 962 delay(1); 963 FDDESELECT(umask); 964 965 for (idb = 0x80000000; idb; idb >>= 1) { 966 FDSELECT(umask); 967 delay(1); 968 if (FDTESTC(FDB_READY) == 0) 969 id |= idb; 970 FDDESELECT(umask); 971 delay(1); 972 } 973 #ifdef FDDEBUG 974 printf("fdcgettype unit %d id 0x%lx\n", unit, id); 975 #endif 976 977 for (cnt = 0, ftp = fdtype; cnt < nfdtype; ftp++, cnt++) 978 if (ftp->driveid == id) 979 return(ftp); 980 /* 981 * 3.5dd's at unit 0 do not always return id. 982 */ 983 if (unit == 0) 984 return(fdtype); 985 return(NULL); 986 } 987 988 /* 989 * turn motor off if possible otherwise mark as needed and will be done 990 * later. 991 */ 992 void 993 fdmotoroff(void *arg) 994 { 995 struct fd_softc *sc; 996 int s; 997 998 sc = arg; 999 s = splbio(); 1000 1001 #ifdef FDDEBUG 1002 printf("fdmotoroff: unit %d\n", sc->hwunit); 1003 #endif 1004 if ((sc->flags & FDF_MOTORON) == 0) 1005 goto done; 1006 /* 1007 * if we have a timeout on a DMA operation let fddmadone() 1008 * deal with it. 1009 */ 1010 if (fdc_indma == sc) { 1011 fddmadone(sc, 1); 1012 goto done; 1013 } 1014 #ifdef FDDEBUG 1015 printf(" motor was on, turning off\n"); 1016 #endif 1017 1018 /* 1019 * flush cache if needed 1020 */ 1021 if (sc->flags & FDF_DIRTY) { 1022 sc->flags |= FDF_JUSTFLUSH | FDF_MOTOROFF; 1023 #ifdef FDDEBUG 1024 printf(" flushing dirty buffer first\n"); 1025 #endif 1026 /* 1027 * if DMA'ing done for now, fddone() will call us again 1028 */ 1029 if (fdc_indma) 1030 goto done; 1031 fddmastart(sc, sc->cachetrk); 1032 goto done; 1033 } 1034 1035 /* 1036 * if controller is busy just schedule us to be called back 1037 */ 1038 if (fdc_indma) { 1039 /* 1040 * someone else has the controller now 1041 * just set flag and let fddone() call us again. 1042 */ 1043 sc->flags |= FDF_MOTOROFF; 1044 goto done; 1045 } 1046 1047 #ifdef FDDEBUG 1048 printf(" hw turning unit off\n"); 1049 #endif 1050 1051 sc->flags &= ~(FDF_MOTORON | FDF_MOTOROFF); 1052 FDDESELECT(FDCUNITMASK); 1053 FDSETMOTOR(0); 1054 delay(1); 1055 FDSELECT(sc->unitmask); 1056 delay(4); 1057 FDDESELECT(sc->unitmask); 1058 delay(1); 1059 if (sc->flags & FDF_WMOTOROFF) 1060 wakeup(fdmotoroff); 1061 done: 1062 splx(s); 1063 } 1064 1065 /* 1066 * select drive seek to track exit with motor on. 1067 * fdsetpos(x, 0, 0) does calibrates the drive. 1068 */ 1069 void 1070 fdsetpos(struct fd_softc *sc, int trk, int towrite) 1071 { 1072 int nstep, sdir, ondly, ncyl, nside; 1073 1074 FDDESELECT(FDCUNITMASK); 1075 FDSETMOTOR(1); 1076 delay(1); 1077 FDSELECT(sc->unitmask); 1078 delay(1); 1079 if ((sc->flags & FDF_MOTORON) == 0) { 1080 ondly = 0; 1081 while (FDTESTC(FDB_READY) == 0) { 1082 delay(1000); 1083 if (++ondly >= 1000) 1084 break; 1085 } 1086 } 1087 sc->flags |= FDF_MOTORON; 1088 1089 ncyl = trk / FDNHEADS; 1090 nside = trk % FDNHEADS; 1091 1092 if (sc->curcyl == ncyl && fdc_side == nside) 1093 return; 1094 1095 if (towrite) 1096 sc->flags |= FDF_WRITEWAIT; 1097 1098 #ifdef FDDEBUG 1099 printf("fdsetpos: cyl %d head %d towrite %d\n", trk / FDNHEADS, 1100 trk % FDNHEADS, towrite); 1101 #endif 1102 nstep = ncyl - sc->curcyl; 1103 if (nstep) { 1104 /* 1105 * figure direction 1106 */ 1107 if (nstep > 0 && ncyl != 0) { 1108 sdir = FDSTEPIN; 1109 FDSETDIR(1); 1110 } else { 1111 nstep = -nstep; 1112 sdir = FDSTEPOUT; 1113 FDSETDIR(0); 1114 } 1115 if (ncyl == 0) { 1116 /* 1117 * either just want cylinder 0 or doing 1118 * a calibrate. 1119 */ 1120 nstep = 256; 1121 while (FDTESTC(FDB_CYLZERO) == 0 && nstep--) { 1122 FDSTEP; 1123 delay(sc->stepdelay); 1124 } 1125 if (nstep < 0) 1126 sc->flags |= FDF_NOTRACK0; 1127 } else { 1128 /* 1129 * step the needed amount amount. 1130 */ 1131 while (nstep--) { 1132 FDSTEP; 1133 delay(sc->stepdelay); 1134 } 1135 } 1136 /* 1137 * if switched directions 1138 * allow drive to settle. 1139 */ 1140 if (sc->pstepdir != sdir) 1141 delay(FDSETTLEDELAY); 1142 sc->pstepdir = sdir; 1143 sc->curcyl = ncyl; 1144 } 1145 if (nside == fdc_side) 1146 return; 1147 /* 1148 * select side 1149 */ 1150 fdc_side = nside; 1151 FDSETHEAD(nside); 1152 delay(FDPRESIDEDELAY); 1153 } 1154 1155 void 1156 fdselunit(struct fd_softc *sc) 1157 { 1158 FDDESELECT(FDCUNITMASK); /* deselect all */ 1159 FDSETMOTOR(sc->flags & FDF_MOTORON); /* set motor to unit's state */ 1160 delay(1); 1161 FDSELECT(sc->unitmask); /* select unit */ 1162 delay(1); 1163 } 1164 1165 /* 1166 * process next buf on device queue. 1167 * normall sequence of events: 1168 * fdstart() -> fddmastart(); 1169 * fdidxintr(); 1170 * fdintr() -> fddmadone() -> fddone(); 1171 * if the track is in the cache then fdstart() will short-circuit 1172 * to fddone() else if the track cache is dirty it will flush. If 1173 * the buf is not an entire track it will cache the requested track. 1174 */ 1175 void 1176 fdstart(struct fd_softc *sc) 1177 { 1178 int trk, error, write; 1179 struct buf *bp, *dp; 1180 int changed; 1181 1182 #ifdef FDDEBUG 1183 printf("fdstart: unit %d\n", sc->hwunit); 1184 #endif 1185 1186 /* 1187 * if DMA'ing just return. we must have been called from fdstartegy. 1188 */ 1189 if (fdc_indma) 1190 return; 1191 1192 /* 1193 * get next buf if there. 1194 */ 1195 dp = &sc->curbuf; 1196 if ((bp = bufq_peek(sc->bufq)) == NULL) { 1197 #ifdef FDDEBUG 1198 printf(" nothing to do\n"); 1199 #endif 1200 return; 1201 } 1202 1203 /* 1204 * Mark us as busy now, in case fddone() gets called in one 1205 * of the cases below. 1206 */ 1207 disk_busy(&sc->dkdev); 1208 1209 /* 1210 * make sure same disk is loaded 1211 */ 1212 fdselunit(sc); 1213 changed = FDTESTC(FDB_CHANGED); 1214 FDDESELECT(sc->unitmask); 1215 if (changed) { 1216 /* 1217 * disk missing, invalidate all future io on 1218 * this unit until re-open()'ed also invalidate 1219 * all current io 1220 */ 1221 printf("fdstart: disk changed\n"); 1222 #ifdef FDDEBUG 1223 printf(" disk was removed invalidating all io\n"); 1224 #endif 1225 sc->flags &= ~FDF_HAVELABEL; 1226 for (;;) { 1227 bp = bufq_get(sc->bufq); 1228 bp->b_error = EIO; 1229 if (bufq_peek(sc->bufq) == NULL) 1230 break; 1231 biodone(bp); 1232 } 1233 /* 1234 * do fddone() on last buf to allow other units to start. 1235 */ 1236 bufq_put(sc->bufq, bp); 1237 fddone(sc); 1238 return; 1239 } 1240 1241 /* 1242 * we have a valid buf, setup our local version 1243 * we use this count to allow reading over multiple tracks. 1244 * into a single buffer 1245 */ 1246 dp->b_bcount = bp->b_bcount; 1247 dp->b_blkno = bp->b_blkno; 1248 dp->b_data = bp->b_data; 1249 dp->b_flags = bp->b_flags; 1250 dp->b_resid = 0; 1251 1252 if (bp->b_flags & B_READ) 1253 write = 0; 1254 else if (FDTESTC(FDB_PROTECT) == 0) 1255 write = 1; 1256 else { 1257 error = EPERM; 1258 goto done; 1259 } 1260 1261 /* 1262 * figure trk given blkno 1263 */ 1264 trk = bp->b_blkno / sc->nsectors; 1265 1266 /* 1267 * check to see if same as currently cached track 1268 * if so we need to do no DMA read. 1269 */ 1270 if (trk == sc->cachetrk) { 1271 fddone(sc); 1272 return; 1273 } 1274 1275 /* 1276 * if we will be overwriting the entire cache, don't bother to 1277 * fetch it. 1278 */ 1279 if (bp->b_bcount == (sc->nsectors * FDSECSIZE) && write && 1280 bp->b_blkno % sc->nsectors == 0) { 1281 if (sc->flags & FDF_DIRTY) 1282 sc->flags |= FDF_JUSTFLUSH; 1283 else { 1284 sc->cachetrk = trk; 1285 fddone(sc); 1286 return; 1287 } 1288 } 1289 1290 /* 1291 * start DMA read of `trk' 1292 */ 1293 fddmastart(sc, trk); 1294 return; 1295 done: 1296 bp->b_error = error; 1297 fddone(sc); 1298 } 1299 1300 /* 1301 * continue a started operation on next track. always begin at 1302 * sector 0 on the next track. 1303 */ 1304 void 1305 fdcont(struct fd_softc *sc) 1306 { 1307 struct buf *dp, *bp; 1308 int trk, write; 1309 1310 dp = &sc->curbuf; 1311 bp = bufq_peek(sc->bufq); 1312 dp->b_data = (char*)dp->b_data + (dp->b_bcount - bp->b_resid); 1313 dp->b_blkno += (dp->b_bcount - bp->b_resid) / FDSECSIZE; 1314 dp->b_bcount = bp->b_resid; 1315 1316 /* 1317 * figure trk given blkno 1318 */ 1319 trk = dp->b_blkno / sc->nsectors; 1320 #ifdef DEBUG 1321 if (trk != sc->cachetrk + 1 || dp->b_blkno % sc->nsectors != 0) 1322 panic("fdcont: confused"); 1323 #endif 1324 if (dp->b_flags & B_READ) 1325 write = 0; 1326 else 1327 write = 1; 1328 /* 1329 * if we will be overwriting the entire cache, don't bother to 1330 * fetch it. 1331 */ 1332 if (dp->b_bcount == (sc->nsectors * FDSECSIZE) && write) { 1333 if (sc->flags & FDF_DIRTY) 1334 sc->flags |= FDF_JUSTFLUSH; 1335 else { 1336 sc->cachetrk = trk; 1337 fddone(sc); 1338 return; 1339 } 1340 } 1341 /* 1342 * start DMA read of `trk' 1343 */ 1344 fddmastart(sc, trk); 1345 return; 1346 } 1347 1348 void 1349 fddmastart(struct fd_softc *sc, int trk) 1350 { 1351 int adkmask, ndmaw, write, dmatrk; 1352 1353 #ifdef FDDEBUG 1354 printf("fddmastart: unit %d cyl %d head %d", sc->hwunit, 1355 trk / FDNHEADS, trk % FDNHEADS); 1356 #endif 1357 /* 1358 * flush the cached track if dirty else read requested track. 1359 */ 1360 if (sc->flags & FDF_DIRTY) { 1361 fdcachetoraw(sc); 1362 ndmaw = sc->type->nwritew; 1363 dmatrk = sc->cachetrk; 1364 write = 1; 1365 } else { 1366 ndmaw = sc->type->nreadw; 1367 dmatrk = trk; 1368 write = 0; 1369 } 1370 1371 #ifdef FDDEBUG 1372 printf(" %s", write ? " flushing cache\n" : " loading cache\n"); 1373 #endif 1374 sc->cachetrk = trk; 1375 fdc_indma = sc; 1376 fdsetpos(sc, dmatrk, write); 1377 1378 /* 1379 * setup dma stuff 1380 */ 1381 if (write == 0) { 1382 custom.adkcon = ADKF_MSBSYNC; 1383 custom.adkcon = ADKF_SETCLR | ADKF_WORDSYNC | ADKF_FAST; 1384 custom.dsksync = FDMFMSYNC; 1385 } else { 1386 custom.adkcon = ADKF_PRECOMP1 | ADKF_PRECOMP0 | ADKF_WORDSYNC | 1387 ADKF_MSBSYNC; 1388 adkmask = ADKF_SETCLR | ADKF_FAST | ADKF_MFMPREC; 1389 if (dmatrk >= sc->type->precomp[0]) 1390 adkmask |= ADKF_PRECOMP0; 1391 if (dmatrk >= sc->type->precomp[1]) 1392 adkmask |= ADKF_PRECOMP1; 1393 custom.adkcon = adkmask; 1394 } 1395 custom.dskpt = (u_char *)kvtop(fdc_dmap); 1396 1397 /* 1398 * If writing an MSDOS track, activate disk index pulse 1399 * interrupt, DMA will be started in the intr routine fdidxintr() 1400 * Otherwise, start the DMA here. 1401 */ 1402 if (write && sc->openpart == FDMSDOSPART) { 1403 fdc_dmalen = ndmaw; 1404 fdc_dmawrite = write; 1405 ciab.icr = CIA_ICR_IR_SC | CIA_ICR_FLG; 1406 } else { 1407 FDDMASTART(ndmaw, write); 1408 fdc_dmalen = 0; 1409 } 1410 1411 #ifdef FDDEBUG 1412 printf(" DMA started\n"); 1413 #endif 1414 } 1415 1416 /* 1417 * recalibrate the drive 1418 */ 1419 void 1420 fdcalibrate(void *arg) 1421 { 1422 struct fd_softc *sc; 1423 static int loopcnt; 1424 1425 sc = arg; 1426 1427 if (loopcnt == 0) { 1428 /* 1429 * seek cyl 0 1430 */ 1431 fdc_indma = sc; 1432 sc->stepdelay += 900; 1433 if (sc->cachetrk > 1) 1434 fdsetpos(sc, sc->cachetrk % FDNHEADS, 0); 1435 sc->stepdelay -= 900; 1436 } 1437 if (loopcnt++ & 1) 1438 fdsetpos(sc, sc->cachetrk, 0); 1439 else 1440 fdsetpos(sc, sc->cachetrk + FDNHEADS, 0); 1441 /* 1442 * trk++, trk, trk++, trk, trk++, trk, trk++, trk and DMA 1443 */ 1444 if (loopcnt < 8) 1445 callout_reset(&sc->calibrate_ch, hz / 8, fdcalibrate, sc); 1446 else { 1447 loopcnt = 0; 1448 fdc_indma = NULL; 1449 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1450 fddmastart(sc, sc->cachetrk); 1451 } 1452 } 1453 1454 void 1455 fddmadone(struct fd_softc *sc, int timeo) 1456 { 1457 #ifdef FDDEBUG 1458 printf("fddmadone: unit %d, timeo %d\n", sc->hwunit, timeo); 1459 #endif 1460 fdc_indma = NULL; 1461 callout_stop(&sc->motor_ch); 1462 FDDMASTOP; 1463 1464 /* 1465 * guarantee the drive has been at current head and cyl 1466 * for at least FDWRITEDELAY after a write. 1467 */ 1468 if (sc->flags & FDF_WRITEWAIT) { 1469 delay(FDWRITEDELAY); 1470 sc->flags &= ~FDF_WRITEWAIT; 1471 } 1472 1473 if ((sc->flags & FDF_MOTOROFF) == 0) { 1474 /* 1475 * motor runs for 1.5 seconds after last DMA 1476 */ 1477 callout_reset(&sc->motor_ch, 3 * hz / 2, fdmotoroff, sc); 1478 } 1479 if (sc->flags & FDF_DIRTY) { 1480 /* 1481 * if buffer dirty, the last DMA cleaned it 1482 */ 1483 sc->flags &= ~FDF_DIRTY; 1484 if (timeo) 1485 aprint_error_dev(sc->sc_dev, 1486 "write of track cache timed out.\n"); 1487 if (sc->flags & FDF_JUSTFLUSH) { 1488 sc->flags &= ~FDF_JUSTFLUSH; 1489 /* 1490 * we are done DMA'ing 1491 */ 1492 fddone(sc); 1493 return; 1494 } 1495 /* 1496 * load the cache 1497 */ 1498 fddmastart(sc, sc->cachetrk); 1499 return; 1500 } 1501 #ifdef FDDEBUG 1502 else if (sc->flags & FDF_MOTOROFF) 1503 panic("fddmadone: FDF_MOTOROFF with no FDF_DIRTY"); 1504 #endif 1505 1506 /* 1507 * cache loaded decode it into cache buffer 1508 */ 1509 if (timeo == 0 && fdrawtocache(sc) == 0) 1510 sc->retried = 0; 1511 else { 1512 #ifdef FDDEBUG 1513 if (timeo) 1514 aprint_debug_dev(sc->sc_dev, 1515 "fddmadone: cache load timed out.\n"); 1516 #endif 1517 if (sc->retried >= sc->retries) { 1518 sc->retried = 0; 1519 sc->cachetrk = -1; 1520 } else { 1521 sc->retried++; 1522 /* 1523 * this will be restarted at end of calibrate loop. 1524 */ 1525 callout_stop(&sc->motor_ch); 1526 fdcalibrate(sc); 1527 return; 1528 } 1529 } 1530 fddone(sc); 1531 } 1532 1533 void 1534 fddone(struct fd_softc *sc) 1535 { 1536 struct buf *dp, *bp; 1537 char *data; 1538 int sz; 1539 1540 #ifdef FDDEBUG 1541 printf("fddone: unit %d\n", sc->hwunit); 1542 #endif 1543 /* 1544 * check to see if unit is just flushing the cache, 1545 * that is we have no io queued. 1546 */ 1547 if (sc->flags & FDF_MOTOROFF) 1548 goto nobuf; 1549 1550 dp = &sc->curbuf; 1551 if ((bp = bufq_peek(sc->bufq)) == NULL) 1552 panic ("fddone"); 1553 /* 1554 * check for an error that may have occurred 1555 * while getting the track. 1556 */ 1557 if (sc->cachetrk == -1) { 1558 sc->retried = 0; 1559 bp->b_error = EIO; 1560 } else if (bp->b_error == 0) { 1561 data = sc->cachep; 1562 /* 1563 * get offset of data in track cache and limit 1564 * the copy size to not exceed the cache's end. 1565 */ 1566 data += (dp->b_blkno % sc->nsectors) * FDSECSIZE; 1567 sz = sc->nsectors - dp->b_blkno % sc->nsectors; 1568 sz *= FDSECSIZE; 1569 sz = min(dp->b_bcount, sz); 1570 if (bp->b_flags & B_READ) 1571 memcpy(dp->b_data, data, sz); 1572 else { 1573 memcpy(data, dp->b_data, sz); 1574 sc->flags |= FDF_DIRTY; 1575 } 1576 bp->b_resid = dp->b_bcount - sz; 1577 if (bp->b_resid == 0) { 1578 bp->b_error = 0; 1579 } else { 1580 /* 1581 * not done yet need to read next track 1582 */ 1583 fdcont(sc); 1584 return; 1585 } 1586 } 1587 /* 1588 * remove from queue. 1589 */ 1590 (void)bufq_get(sc->bufq); 1591 1592 disk_unbusy(&sc->dkdev, (bp->b_bcount - bp->b_resid), 1593 (bp->b_flags & B_READ)); 1594 1595 biodone(bp); 1596 nobuf: 1597 fdfindwork(device_unit(sc->sc_dev)); 1598 } 1599 1600 void 1601 fdfindwork(int unit) 1602 { 1603 struct fd_softc *ssc, *sc; 1604 int i, last; 1605 1606 /* 1607 * first see if we have any fdopen()'s waiting 1608 */ 1609 if (fdc_wantwakeup) { 1610 wakeup(fdopen); 1611 fdc_wantwakeup--; 1612 return; 1613 } 1614 1615 /* 1616 * start next available unit, linear search from the next unit 1617 * wrapping and finally this unit. 1618 */ 1619 last = 0; 1620 ssc = NULL; 1621 for (i = unit + 1; last == 0; i++) { 1622 if (i == unit) 1623 last = 1; 1624 if (i >= fd_cd.cd_ndevs) { 1625 i = -1; 1626 continue; 1627 } 1628 if ((sc = device_lookup_private(&fd_cd, i)) == NULL) 1629 continue; 1630 1631 /* 1632 * if unit has requested to be turned off 1633 * and it has no buf's queued do it now 1634 */ 1635 if (sc->flags & FDF_MOTOROFF) { 1636 if (bufq_peek(sc->bufq) == NULL) 1637 fdmotoroff(sc); 1638 else { 1639 /* 1640 * we gained a buf request while 1641 * we waited, forget the motoroff 1642 */ 1643 sc->flags &= ~FDF_MOTOROFF; 1644 } 1645 /* 1646 * if we now have DMA unit must have needed 1647 * flushing, quit 1648 */ 1649 if (fdc_indma) 1650 return; 1651 } 1652 /* 1653 * if we have no start unit and the current unit has 1654 * io waiting choose this unit to start. 1655 */ 1656 if (ssc == NULL && bufq_peek(sc->bufq) != NULL) 1657 ssc = sc; 1658 } 1659 if (ssc) 1660 fdstart(ssc); 1661 } 1662 1663 /* 1664 * min byte count to whats left of the track in question 1665 */ 1666 void 1667 fdminphys(struct buf *bp) 1668 { 1669 struct fd_softc *sc; 1670 int sec, toff, tsz; 1671 1672 if ((sc = getsoftc(fd_cd, FDUNIT(bp->b_dev))) == NULL) 1673 panic("fdminphys: couldn't get softc"); 1674 1675 sec = bp->b_blkno % sc->nsectors; 1676 1677 toff = sec * FDSECSIZE; 1678 tsz = sc->nsectors * FDSECSIZE; 1679 #ifdef FDDEBUG 1680 printf("fdminphys: before %ld", bp->b_bcount); 1681 #endif 1682 bp->b_bcount = min(bp->b_bcount, tsz - toff); 1683 #ifdef FDDEBUG 1684 printf(" after %ld\n", bp->b_bcount); 1685 #endif 1686 minphys(bp); 1687 } 1688 1689 /* 1690 * encode the track cache into raw MFM ready for DMA 1691 * when we go to multiple disk formats, this will call type dependent 1692 * functions 1693 */ 1694 void fdcachetoraw(struct fd_softc *sc) 1695 { 1696 if (sc->openpart == FDMSDOSPART) 1697 mscachetoraw(sc); 1698 else 1699 amcachetoraw(sc); 1700 } 1701 1702 /* 1703 * decode raw MFM from DMA into units track cache. 1704 * when we go to multiple disk formats, this will call type dependent 1705 * functions 1706 */ 1707 int 1708 fdrawtocache(struct fd_softc *sc) 1709 { 1710 1711 if (sc->openpart == FDMSDOSPART) 1712 return(msrawtocache(sc)); 1713 else 1714 return(amrawtocache(sc)); 1715 } 1716 1717 void 1718 amcachetoraw(struct fd_softc *sc) 1719 { 1720 static u_long mfmnull[4]; 1721 u_long *rp, *crp, *dp, hcksum, dcksum, info; 1722 int sec, i; 1723 1724 rp = fdc_dmap; 1725 1726 /* 1727 * not yet one sector (- 1 long) gap. 1728 * for now use previous drivers values 1729 */ 1730 for (i = 0; i < sc->type->gap; i++) 1731 *rp++ = 0xaaaaaaaa; 1732 /* 1733 * process sectors 1734 */ 1735 dp = sc->cachep; 1736 info = 0xff000000 | (sc->cachetrk << 16) | sc->nsectors; 1737 for (sec = 0; sec < sc->nsectors; sec++, info += (1 << 8) - 1) { 1738 hcksum = dcksum = 0; 1739 /* 1740 * sector format 1741 * offset description 1742 *----------------------------------- 1743 * 0 null 1744 * 1 sync 1745 * oddbits evenbits 1746 *---------------------- 1747 * 2 3 [0xff]b [trk]b [sec]b [togap]b 1748 * 4-7 8-11 null 1749 * 12 13 header cksum [2-11] 1750 * 14 15 data cksum [16-271] 1751 * 16-143 144-271 data 1752 */ 1753 *rp = 0xaaaaaaaa; 1754 if (*(rp - 1) & 0x1) 1755 *rp &= 0x7fffffff; /* clock bit correction */ 1756 rp++; 1757 *rp++ = (FDMFMSYNC << 16) | FDMFMSYNC; 1758 rp = mfmblkencode(&info, rp, &hcksum, 1); 1759 rp = mfmblkencode(mfmnull, rp, &hcksum, 4); 1760 rp = mfmblkencode(&hcksum, rp, NULL, 1); 1761 1762 crp = rp; 1763 rp = mfmblkencode(dp, rp + 2, &dcksum, FDSECLWORDS); 1764 dp += FDSECLWORDS; 1765 crp = mfmblkencode(&dcksum, crp, NULL, 1); 1766 if (*(crp - 1) & 0x1) 1767 *crp &= 0x7fffffff; /* clock bit correction */ 1768 else if ((*crp & 0x40000000) == 0) 1769 *crp |= 0x80000000; 1770 } 1771 *rp = 0xaaa80000; 1772 if (*(rp - 1) & 0x1) 1773 *rp &= 0x7fffffff; 1774 } 1775 1776 u_long * 1777 fdfindsync(u_long *rp, u_long *ep) 1778 { 1779 u_short *sp; 1780 1781 sp = (u_short *)rp; 1782 while ((u_long *)sp < ep && *sp != FDMFMSYNC) 1783 sp++; 1784 while ((u_long *)sp < ep && *sp == FDMFMSYNC) 1785 sp++; 1786 if ((u_long *)sp < ep) 1787 return((u_long *)sp); 1788 return(NULL); 1789 } 1790 1791 int 1792 amrawtocache(struct fd_softc *sc) 1793 { 1794 u_long mfmnull[4]; 1795 u_long *dp, *rp, *erp, *crp, *srp, hcksum, dcksum, info, cktmp; 1796 int cnt, doagain; 1797 1798 doagain = 1; 1799 srp = rp = fdc_dmap; 1800 erp = (u_long *)((u_short *)rp + sc->type->nreadw); 1801 cnt = 0; 1802 again: 1803 if (doagain == 0 || (rp = srp = fdfindsync(srp, erp)) == NULL) { 1804 #ifdef DIAGNOSTIC 1805 aprint_error_dev(sc->sc_dev, "corrupted track (%d) data.\n", 1806 sc->cachetrk); 1807 #endif 1808 return(-1); 1809 } 1810 1811 /* 1812 * process sectors 1813 */ 1814 for (; cnt < sc->nsectors; cnt++) { 1815 hcksum = dcksum = 0; 1816 rp = mfmblkdecode(rp, &info, &hcksum, 1); 1817 rp = mfmblkdecode(rp, mfmnull, &hcksum, 4); 1818 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1819 if (cktmp != hcksum) { 1820 #ifdef FDDEBUG 1821 printf(" info 0x%lx hchksum 0x%lx trkhcksum 0x%lx\n", 1822 info, hcksum, cktmp); 1823 #endif 1824 goto again; 1825 } 1826 if (((info >> 16) & 0xff) != sc->cachetrk) { 1827 #ifdef DEBUG 1828 aprint_debug_dev(sc->sc_dev, 1829 "incorrect track found: 0x%lx %d\n", 1830 info, sc->cachetrk); 1831 #endif 1832 goto again; 1833 } 1834 #ifdef FDDEBUG 1835 printf(" info 0x%lx\n", info); 1836 #endif 1837 1838 rp = mfmblkdecode(rp, &cktmp, NULL, 1); 1839 dp = sc->cachep; 1840 dp += FDSECLWORDS * ((info >> 8) & 0xff); 1841 crp = mfmblkdecode(rp, dp, &dcksum, FDSECLWORDS); 1842 if (cktmp != dcksum) { 1843 #ifdef FDDEBUG 1844 printf(" info 0x%lx dchksum 0x%lx trkdcksum 0x%lx\n", 1845 info, dcksum, cktmp); 1846 #endif 1847 goto again; 1848 } 1849 1850 /* 1851 * if we are at gap then we can no longer be sure 1852 * of correct sync marks 1853 */ 1854 if ((info & 0xff) == 1) 1855 doagain = 1; 1856 else 1857 doagain = 0; 1858 srp = rp = fdfindsync(crp, erp); 1859 } 1860 return(0); 1861 } 1862 1863 void 1864 mscachetoraw(struct fd_softc *sc) 1865 { 1866 u_short *rp, *erp, crc; 1867 u_char *cp, tb[5]; 1868 int sec, i; 1869 1870 rp = (u_short *)fdc_dmap; 1871 erp = rp + sc->type->nwritew; 1872 cp = sc->cachep; 1873 1874 /* 1875 * initial track filler (828 * GAP1) 1876 */ 1877 for (i = 0; i < sc->type->gap; i++) { 1878 *rp++ = FDMFMGAP1; 1879 *rp++ = FDMFMGAP1; 1880 } 1881 1882 for (sec = 0; sec < sc->nsectors; sec++) { 1883 1884 /* 1885 * leading sector gap 1886 * (12 * GAP2) + (3 * SYNC) 1887 */ 1888 for (i = 0; i < 12; i++) 1889 *rp++ = FDMFMGAP2; 1890 *rp++ = FDMFMSYNC; 1891 *rp++ = FDMFMSYNC; 1892 *rp++ = FDMFMSYNC; 1893 1894 /* 1895 * sector information 1896 * (ID) + track + side + sector + sector size + CRC16 1897 */ 1898 *rp++ = FDMFMID; 1899 tb[0] = sc->cachetrk / FDNHEADS; 1900 tb[1] = sc->cachetrk % FDNHEADS; 1901 tb[2] = sec + 1; 1902 i = sc->bytespersec; 1903 tb[3] = i < 256 ? 0 : (i < 512 ? 1 : (i < 1024 ? 2 : 3)); 1904 rp = msblkencode(rp, tb, 4, &crc); 1905 tb[0] = crc >> 8; 1906 tb[1] = crc & 0xff; 1907 tb[2] = 0x4e; /* GAP1 decoded */ 1908 rp = msblkencode(rp, tb, 3, 0); 1909 1910 /* 1911 * sector info/data gap 1912 * (22 * GAP1) + (12 * GAP2) + (3 * SYNC) 1913 */ 1914 for (i = 0; i < 21; i++) 1915 *rp++ = FDMFMGAP1; 1916 for (i = 0; i < 12; i++) 1917 *rp++ = FDMFMGAP2; 1918 *rp++ = FDMFMSYNC; 1919 *rp++ = FDMFMSYNC; 1920 *rp++ = FDMFMSYNC; 1921 1922 /* 1923 * sector data 1924 * (DATA) + ...data... + CRC16 1925 */ 1926 *rp++ = FDMFMDATA; 1927 rp = msblkencode(rp, cp, sc->bytespersec, &crc); 1928 cp += sc->bytespersec; 1929 tb[0] = crc >> 8; 1930 tb[1] = crc & 0xff; 1931 tb[2] = 0x4e; /* GAP3 decoded */ 1932 rp = msblkencode(rp, tb, 3, 0); 1933 1934 /* 1935 * trailing sector gap 1936 * (80 * GAP3) 1937 */ 1938 for (i = 0; i < 79; i++) 1939 *rp++ = FDMFMGAP3; 1940 } 1941 1942 /* 1943 * fill rest of track with GAP3 1944 */ 1945 while (rp != erp) 1946 *rp++ = FDMFMGAP3; 1947 1948 } 1949 1950 int 1951 msrawtocache(struct fd_softc *sc) 1952 { 1953 u_short *rp, *erp; 1954 u_char tb[5], *cp; 1955 int ct, sec, retry; 1956 1957 rp = (u_short *)fdc_dmap; 1958 erp = rp + sc->type->nreadw; 1959 cp = sc->cachep; 1960 1961 for (ct = 0; ct < sc->nsectors; ct++) { 1962 retry = 1; 1963 do { 1964 /* 1965 * skip leading gap to sync 1966 */ 1967 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) { 1968 #ifdef DIAGNOSTIC 1969 aprint_normal_dev(sc->sc_dev, 1970 "corrupted track (%d) data.\n", 1971 sc->cachetrk); 1972 #endif 1973 return(-1); 1974 } 1975 1976 /* 1977 * Grab sector info 1978 */ 1979 if (*rp++ != FDMFMID) 1980 continue; 1981 rp = msblkdecode(rp, tb, 4); 1982 #ifdef FDDEBUG 1983 printf("sector id: sector %d, track %d, side %d," 1984 "bps %d\n", tb[2], tb[0], tb[1], 128 << tb[3]); 1985 #endif 1986 if ((tb[0] * FDNHEADS + tb[1]) != sc->cachetrk || 1987 tb[2] > sc->nsectors) 1988 continue; 1989 1990 sec = tb[2]; 1991 sc->bytespersec = 128 << tb[3]; 1992 rp += 2; /* skip CRC-16 */ 1993 1994 /* 1995 * skip gap and read in data 1996 */ 1997 if ((rp = (u_short *)fdfindsync((u_long *)rp, (u_long *)erp)) == NULL) 1998 return(-1); 1999 if (*rp++ != FDMFMDATA) 2000 continue; 2001 rp = msblkdecode(rp, cp + ((sec-1) * sc->bytespersec), 2002 sc->bytespersec); 2003 rp += 2; /* skip CRC-16 */ 2004 2005 retry = 0; 2006 } while (retry); 2007 } 2008 return(0); 2009 } 2010 2011 /* 2012 * encode len longwords of `dp' data in amiga mfm block format (`rp') 2013 * this format specified that the odd bits are at current pos and even 2014 * bits at len + current pos 2015 */ 2016 u_long * 2017 mfmblkencode(u_long *dp, u_long *rp, u_long *cp, int len) 2018 { 2019 u_long *sdp, *edp, d, dtmp, correct; 2020 2021 sdp = dp; 2022 edp = dp + len; 2023 2024 if (*(rp - 1) & 0x1) 2025 correct = 1; 2026 else 2027 correct = 0; 2028 /* 2029 * do odd bits 2030 */ 2031 while (dp < edp) { 2032 d = (*dp >> 1) & 0x55555555; /* remove clock bits */ 2033 dtmp = d ^ 0x55555555; 2034 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2035 /* 2036 * correct upper clock bit if needed 2037 */ 2038 if (correct) 2039 d &= 0x7fffffff; 2040 if (d & 0x1) 2041 correct = 1; 2042 else 2043 correct = 0; 2044 /* 2045 * do checksums and store in raw buffer 2046 */ 2047 if (cp) 2048 *cp ^= d; 2049 *rp++ = d; 2050 dp++; 2051 } 2052 /* 2053 * do even bits 2054 */ 2055 dp = sdp; 2056 while (dp < edp) { 2057 d = *dp & 0x55555555; /* remove clock bits */ 2058 dtmp = d ^ 0x55555555; 2059 d |= ((dtmp >> 1) | 0x80000000) & (dtmp << 1); 2060 /* 2061 * correct upper clock bit if needed 2062 */ 2063 if (correct) 2064 d &= 0x7fffffff; 2065 if (d & 0x1) 2066 correct = 1; 2067 else 2068 correct = 0; 2069 /* 2070 * do checksums and store in raw buffer 2071 */ 2072 if (cp) 2073 *cp ^= d; 2074 *rp++ = d; 2075 dp++; 2076 } 2077 if (cp) 2078 *cp &= 0x55555555; 2079 return(rp); 2080 } 2081 2082 /* 2083 * decode len longwords of `dp' data in amiga mfm block format (`rp') 2084 * this format specified that the odd bits are at current pos and even 2085 * bits at len + current pos 2086 */ 2087 u_long * 2088 mfmblkdecode(u_long *rp, u_long *dp, u_long *cp, int len) 2089 { 2090 u_long o, e; 2091 int cnt; 2092 2093 cnt = len; 2094 while (cnt--) { 2095 o = *rp; 2096 e = *(rp + len); 2097 if (cp) { 2098 *cp ^= o; 2099 *cp ^= e; 2100 } 2101 o &= 0x55555555; 2102 e &= 0x55555555; 2103 *dp++ = (o << 1) | e; 2104 rp++; 2105 } 2106 if (cp) 2107 *cp &= 0x55555555; 2108 return(rp + len); 2109 } 2110 2111 /* 2112 * decode len words in standard MFM format to len bytes 2113 * of data. 2114 */ 2115 u_short * 2116 msblkdecode(u_short *rp, u_char *cp, int len) 2117 { 2118 while (len--) { 2119 *cp++ = msdecode[*rp & 0x7f] | 2120 (msdecode[(*rp >> 8) & 0x7f] << 4); 2121 rp++; 2122 } 2123 2124 return(rp); 2125 } 2126 2127 /* 2128 * encode len bytes of data into len words in standard MFM format. 2129 * If a pointer is supplied for crc, calculate the CRC-16 of the data 2130 * as well. 2131 */ 2132 u_short * 2133 msblkencode(u_short *rp, u_char *cp, int len, u_short *crc) 2134 { 2135 u_short td; 2136 u_short mycrc; 2137 2138 /* preload crc for header (4 bytes) 2139 * or data (anything else) 2140 */ 2141 mycrc = (len == 4) ? 0xb230 : 0xe295; 2142 2143 while (len--) { 2144 td = (msencode[*cp >> 4] << 8) | msencode[*cp & 0x0f]; 2145 2146 /* Check for zeros in top bit of encode and bottom 2147 * bit of previous encode. if so, slap a one in betweem 2148 * them. 2149 */ 2150 if ((td & 0x140) == 0) 2151 td |= 0x80; 2152 if ((td & 0x4000) == 0 && (rp[-1] & 1) == 0) 2153 td |= 0x8000; 2154 2155 *rp++ = td; 2156 2157 /* 2158 * calc crc if requested 2159 */ 2160 if (crc) 2161 mycrc = (mycrc << 8) ^ mscrctab[*cp ^ (mycrc >> 8)]; 2162 2163 cp++; 2164 } 2165 2166 if (crc) 2167 *crc = mycrc; 2168 2169 return(rp); 2170 } 2171
Indexes created Thu Oct 02 14:10:14 GMT 2025