sys/x86/isa/clock.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1990 The Regents of the University of California.
   5  * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
   6  * All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * William Jolitz and Don Ahn.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  *      from: @(#)clock.c       7.2 (Berkeley) 5/12/91
  36  */
  37
  38 #include <sys/cdefs.h>
  39 __FBSDID("$FreeBSD$");
  40
  41 /*
  42  * Routines to handle clock hardware.
  43  */
  44
  45 #include "opt_clock.h"
  46 #include "opt_isa.h"
  47
  48 #include <sys/param.h>
  49 #include <sys/systm.h>
  50 #include <sys/bus.h>
  51 #include <sys/lock.h>
  52 #include <sys/kdb.h>
  53 #include <sys/mutex.h>
  54 #include <sys/proc.h>
  55 #include <sys/kernel.h>
  56 #include <sys/module.h>
  57 #include <sys/rman.h>
  58 #include <sys/sched.h>
  59 #include <sys/smp.h>
  60 #include <sys/sysctl.h>
  61 #include <sys/timeet.h>
  62 #include <sys/timetc.h>
  63
  64 #include <machine/clock.h>
  65 #include <machine/cpu.h>
  66 #include <machine/intr_machdep.h>
  67 #include <machine/ppireg.h>
  68 #include <machine/timerreg.h>
  69 #include <x86/init.h>
  70
  71 #include <isa/rtc.h>
  72 #ifdef DEV_ISA
  73 #include <isa/isareg.h>
  74 #include <isa/isavar.h>
  75 #endif
  76
  77 int     clkintr_pending;
  78 #ifndef TIMER_FREQ
  79 #define TIMER_FREQ   1193182
  80 #endif
  81 u_int   i8254_freq = TIMER_FREQ;
  82 TUNABLE_INT("hw.i8254.freq", &i8254_freq);
  83 int     i8254_max_count;
  84 static int i8254_timecounter = 1;
  85
  86 static  struct mtx clock_lock;
  87 static  struct intsrc *i8254_intsrc;
  88 static  uint16_t i8254_lastcount;
  89 static  uint16_t i8254_offset;
  90 static  int     (*i8254_pending)(struct intsrc *);
  91 static  int     i8254_ticked;
  92
  93 struct attimer_softc {
  94         int intr_en;
  95         int port_rid, intr_rid;
  96         struct resource *port_res;
  97         struct resource *intr_res;
  98         void *intr_handler;
  99         struct timecounter tc;
 100         struct eventtimer et;
 101         int             mode;
 102 #define MODE_STOP       0
 103 #define MODE_PERIODIC   1
 104 #define MODE_ONESHOT    2
 105         uint32_t        period;
 106 };
 107 static struct attimer_softc *attimer_sc = NULL;
 108
 109 static int timer0_period = -2;
 110 static int timer0_mode = 0xffff;
 111 static int timer0_last = 0xffff;
 112
 113 /* Values for timerX_state: */
 114 #define RELEASED        0
 115 #define RELEASE_PENDING 1
 116 #define ACQUIRED        2
 117 #define ACQUIRE_PENDING 3
 118
 119 static  u_char  timer2_state;
 120
 121 static  unsigned i8254_get_timecount(struct timecounter *tc);
 122 static  void    set_i8254_freq(int mode, uint32_t period);
 123
 124 void
 125 clock_init(void)
 126 {
 127         /* Init the clock lock */
 128         mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_NOPROFILE);
 129         /* Init the clock in order to use DELAY */
 130         init_ops.early_clock_source_init();
 131 }
 132
 133 static int
 134 clkintr(void *arg)
 135 {
 136         struct attimer_softc *sc = (struct attimer_softc *)arg;
 137
 138         if (i8254_timecounter && sc->period != 0) {
 139                 mtx_lock_spin(&clock_lock);
 140                 if (i8254_ticked)
 141                         i8254_ticked = 0;
 142                 else {
 143                         i8254_offset += i8254_max_count;
 144                         i8254_lastcount = 0;
 145                 }
 146                 clkintr_pending = 0;
 147                 mtx_unlock_spin(&clock_lock);
 148         }
 149
 150         if (sc->et.et_active && sc->mode != MODE_STOP)
 151                 sc->et.et_event_cb(&sc->et, sc->et.et_arg);
 152
 153         return (FILTER_HANDLED);
 154 }
 155
 156 int
 157 timer_spkr_acquire(void)
 158 {
 159         int mode;
 160
 161         mode = TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT;
 162
 163         if (timer2_state != RELEASED)
 164                 return (-1);
 165         timer2_state = ACQUIRED;
 166
 167         /*
 168          * This access to the timer registers is as atomic as possible
 169          * because it is a single instruction.  We could do better if we
 170          * knew the rate.  Use of splclock() limits glitches to 10-100us,
 171          * and this is probably good enough for timer2, so we aren't as
 172          * careful with it as with timer0.
 173          */
 174         outb(TIMER_MODE, TIMER_SEL2 | (mode & 0x3f));
 175
 176         ppi_spkr_on();          /* enable counter2 output to speaker */
 177         return (0);
 178 }
 179
 180 int
 181 timer_spkr_release(void)
 182 {
 183
 184         if (timer2_state != ACQUIRED)
 185                 return (-1);
 186         timer2_state = RELEASED;
 187         outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
 188
 189         ppi_spkr_off();         /* disable counter2 output to speaker */
 190         return (0);
 191 }
 192
 193 void
 194 timer_spkr_setfreq(int freq)
 195 {
 196
 197         freq = i8254_freq / freq;
 198         mtx_lock_spin(&clock_lock);
 199         outb(TIMER_CNTR2, freq & 0xff);
 200         outb(TIMER_CNTR2, freq >> 8);
 201         mtx_unlock_spin(&clock_lock);
 202 }
 203
 204 static int
 205 getit(void)
 206 {
 207         int high, low;
 208
 209         mtx_lock_spin(&clock_lock);
 210
 211         /* Select timer0 and latch counter value. */
 212         outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
 213
 214         low = inb(TIMER_CNTR0);
 215         high = inb(TIMER_CNTR0);
 216
 217         mtx_unlock_spin(&clock_lock);
 218         return ((high << 8) | low);
 219 }
 220
 221 /*
 222  * Wait "n" microseconds.
 223  * Relies on timer 1 counting down from (i8254_freq / hz)
 224  * Note: timer had better have been programmed before this is first used!
 225  */
 226 void
 227 i8254_delay(int n)
 228 {
 229         int delta, prev_tick, tick, ticks_left;
 230 #ifdef DELAYDEBUG
 231         int getit_calls = 1;
 232         int n1;
 233         static int state = 0;
 234
 235         if (state == 0) {
 236                 state = 1;
 237                 for (n1 = 1; n1 <= 10000000; n1 *= 10)
 238                         DELAY(n1);
 239                 state = 2;
 240         }
 241         if (state == 1)
 242                 printf("DELAY(%d)...", n);
 243 #endif
 244         /*
 245          * Read the counter first, so that the rest of the setup overhead is
 246          * counted.  Guess the initial overhead is 20 usec (on most systems it
 247          * takes about 1.5 usec for each of the i/o's in getit().  The loop
 248          * takes about 6 usec on a 486/33 and 13 usec on a 386/20.  The
 249          * multiplications and divisions to scale the count take a while).
 250          *
 251          * However, if ddb is active then use a fake counter since reading
 252          * the i8254 counter involves acquiring a lock.  ddb must not do
 253          * locking for many reasons, but it calls here for at least atkbd
 254          * input.
 255          */
 256 #ifdef KDB
 257         if (kdb_active)
 258                 prev_tick = 1;
 259         else
 260 #endif
 261                 prev_tick = getit();
 262         n -= 0;                 /* XXX actually guess no initial overhead */
 263         /*
 264          * Calculate (n * (i8254_freq / 1e6)) without using floating point
 265          * and without any avoidable overflows.
 266          */
 267         if (n <= 0)
 268                 ticks_left = 0;
 269         else if (n < 256)
 270                 /*
 271                  * Use fixed point to avoid a slow division by 1000000.
 272                  * 39099 = 1193182 * 2^15 / 10^6 rounded to nearest.
 273                  * 2^15 is the first power of 2 that gives exact results
 274                  * for n between 0 and 256.
 275                  */
 276                 ticks_left = ((u_int)n * 39099 + (1 << 15) - 1) >> 15;
 277         else
 278                 /*
 279                  * Don't bother using fixed point, although gcc-2.7.2
 280                  * generates particularly poor code for the long long
 281                  * division, since even the slow way will complete long
 282                  * before the delay is up (unless we're interrupted).
 283                  */
 284                 ticks_left = ((u_int)n * (long long)i8254_freq + 999999)
 285                              / 1000000;
 286
 287         while (ticks_left > 0) {
 288 #ifdef KDB
 289                 if (kdb_active) {
 290                         inb(0x84);
 291                         tick = prev_tick - 1;
 292                         if (tick <= 0)
 293                                 tick = i8254_max_count;
 294                 } else
 295 #endif
 296                         tick = getit();
 297 #ifdef DELAYDEBUG
 298                 ++getit_calls;
 299 #endif
 300                 delta = prev_tick - tick;
 301                 prev_tick = tick;
 302                 if (delta < 0) {
 303                         delta += i8254_max_count;
 304                         /*
 305                          * Guard against i8254_max_count being wrong.
 306                          * This shouldn't happen in normal operation,
 307                          * but it may happen if set_i8254_freq() is
 308                          * traced.
 309                          */
 310                         if (delta < 0)
 311                                 delta = 0;
 312                 }
 313                 ticks_left -= delta;
 314         }
 315 #ifdef DELAYDEBUG
 316         if (state == 1)
 317                 printf(" %d calls to getit() at %d usec each\n",
 318                        getit_calls, (n + 5) / getit_calls);
 319 #endif
 320 }
 321
 322 static void
 323 set_i8254_freq(int mode, uint32_t period)
 324 {
 325         int new_count, new_mode;
 326
 327         mtx_lock_spin(&clock_lock);
 328         if (mode == MODE_STOP) {
 329                 if (i8254_timecounter) {
 330                         mode = MODE_PERIODIC;
 331                         new_count = 0x10000;
 332                 } else
 333                         new_count = -1;
 334         } else {
 335                 new_count = min(((uint64_t)i8254_freq * period +
 336                     0x80000000LLU) >> 32, 0x10000);
 337         }
 338         if (new_count == timer0_period)
 339                 goto out;
 340         i8254_max_count = ((new_count & ~0xffff) != 0) ? 0xffff : new_count;
 341         timer0_period = (mode == MODE_PERIODIC) ? new_count : -1;
 342         switch (mode) {
 343         case MODE_STOP:
 344                 new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_16BIT;
 345                 outb(TIMER_MODE, new_mode);
 346                 outb(TIMER_CNTR0, 0);
 347                 outb(TIMER_CNTR0, 0);
 348                 break;
 349         case MODE_PERIODIC:
 350                 new_mode = TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT;
 351                 outb(TIMER_MODE, new_mode);
 352                 outb(TIMER_CNTR0, new_count & 0xff);
 353                 outb(TIMER_CNTR0, new_count >> 8);
 354                 break;
 355         case MODE_ONESHOT:
 356                 if (new_count < 256 && timer0_last < 256) {
 357                         new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_LSB;
 358                         if (new_mode != timer0_mode)
 359                                 outb(TIMER_MODE, new_mode);
 360                         outb(TIMER_CNTR0, new_count & 0xff);
 361                         break;
 362                 }
 363                 new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_16BIT;
 364                 if (new_mode != timer0_mode)
 365                         outb(TIMER_MODE, new_mode);
 366                 outb(TIMER_CNTR0, new_count & 0xff);
 367                 outb(TIMER_CNTR0, new_count >> 8);
 368                 break;
 369         default:
 370                 panic("set_i8254_freq: unknown operational mode");
 371         }
 372         timer0_mode = new_mode;
 373         timer0_last = new_count;
 374 out:
 375         mtx_unlock_spin(&clock_lock);
 376 }
 377
 378 static void
 379 i8254_restore(void)
 380 {
 381
 382         timer0_period = -2;
 383         timer0_mode = 0xffff;
 384         timer0_last = 0xffff;
 385         if (attimer_sc != NULL)
 386                 set_i8254_freq(attimer_sc->mode, attimer_sc->period);
 387         else
 388                 set_i8254_freq(MODE_STOP, 0);
 389 }
 390
 391 /* This is separate from startrtclock() so that it can be called early. */
 392 void
 393 i8254_init(void)
 394 {
 395
 396         set_i8254_freq(MODE_STOP, 0);
 397 }
 398
 399 void
 400 startrtclock()
 401 {
 402
 403         init_TSC();
 404 }
 405
 406 void
 407 cpu_initclocks(void)
 408 {
 409 #ifdef EARLY_AP_STARTUP
 410         struct thread *td;
 411         int i;
 412
 413         td = curthread;
 414         cpu_initclocks_bsp();
 415         CPU_FOREACH(i) {
 416                 if (i == 0)
 417                         continue;
 418                 thread_lock(td);
 419                 sched_bind(td, i);
 420                 thread_unlock(td);
 421                 cpu_initclocks_ap();
 422         }
 423         thread_lock(td);
 424         if (sched_is_bound(td))
 425                 sched_unbind(td);
 426         thread_unlock(td);
 427 #else
 428         cpu_initclocks_bsp();
 429 #endif
 430 }
 431
 432 static int
 433 sysctl_machdep_i8254_freq(SYSCTL_HANDLER_ARGS)
 434 {
 435         int error;
 436         u_int freq;
 437
 438         /*
 439          * Use `i8254' instead of `timer' in external names because `timer'
 440          * is too generic.  Should use it everywhere.
 441          */
 442         freq = i8254_freq;
 443         error = sysctl_handle_int(oidp, &freq, 0, req);
 444         if (error == 0 && req->newptr != NULL) {
 445                 i8254_freq = freq;
 446                 if (attimer_sc != NULL) {
 447                         set_i8254_freq(attimer_sc->mode, attimer_sc->period);
 448                         attimer_sc->tc.tc_frequency = freq;
 449                 } else {
 450                         set_i8254_freq(MODE_STOP, 0);
 451                 }
 452         }
 453         return (error);
 454 }
 455
 456 SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq,
 457     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
 458     0, sizeof(u_int), sysctl_machdep_i8254_freq, "IU",
 459     "i8254 timer frequency");
 460
 461 static unsigned
 462 i8254_get_timecount(struct timecounter *tc)
 463 {
 464         device_t dev = (device_t)tc->tc_priv;
 465         struct attimer_softc *sc = device_get_softc(dev);
 466         register_t flags;
 467         uint16_t count;
 468         u_int high, low;
 469
 470         if (sc->period == 0)
 471                 return (i8254_max_count - getit());
 472
 473 #ifdef __amd64__
 474         flags = read_rflags();
 475 #else
 476         flags = read_eflags();
 477 #endif
 478         mtx_lock_spin(&clock_lock);
 479
 480         /* Select timer0 and latch counter value. */
 481         outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
 482
 483         low = inb(TIMER_CNTR0);
 484         high = inb(TIMER_CNTR0);
 485         count = i8254_max_count - ((high << 8) | low);
 486         if (count < i8254_lastcount ||
 487             (!i8254_ticked && (clkintr_pending ||
 488             ((count < 20 || (!(flags & PSL_I) &&
 489             count < i8254_max_count / 2u)) &&
 490             i8254_pending != NULL && i8254_pending(i8254_intsrc))))) {
 491                 i8254_ticked = 1;
 492                 i8254_offset += i8254_max_count;
 493         }
 494         i8254_lastcount = count;
 495         count += i8254_offset;
 496         mtx_unlock_spin(&clock_lock);
 497         return (count);
 498 }
 499
 500 static int
 501 attimer_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
 502 {
 503         device_t dev = (device_t)et->et_priv;
 504         struct attimer_softc *sc = device_get_softc(dev);
 505
 506         if (period != 0) {
 507                 sc->mode = MODE_PERIODIC;
 508                 sc->period = period;
 509         } else {
 510                 sc->mode = MODE_ONESHOT;
 511                 sc->period = first;
 512         }
 513         if (!sc->intr_en) {
 514                 i8254_intsrc->is_pic->pic_enable_source(i8254_intsrc);
 515                 sc->intr_en = 1;
 516         }
 517         set_i8254_freq(sc->mode, sc->period);
 518         return (0);
 519 }
 520
 521 static int
 522 attimer_stop(struct eventtimer *et)
 523 {
 524         device_t dev = (device_t)et->et_priv;
 525         struct attimer_softc *sc = device_get_softc(dev);
 526
 527         sc->mode = MODE_STOP;
 528         sc->period = 0;
 529         set_i8254_freq(sc->mode, sc->period);
 530         return (0);
 531 }
 532
 533 #ifdef DEV_ISA
 534 /*
 535  * Attach to the ISA PnP descriptors for the timer
 536  */
 537 static struct isa_pnp_id attimer_ids[] = {
 538         { 0x0001d041 /* PNP0100 */, "AT timer" },
 539         { 0 }
 540 };
 541
 542 static int
 543 attimer_probe(device_t dev)
 544 {
 545         int result;
 546
 547         result = ISA_PNP_PROBE(device_get_parent(dev), dev, attimer_ids);
 548         /* ENOENT means no PnP-ID, device is hinted. */
 549         if (result == ENOENT) {
 550                 device_set_desc(dev, "AT timer");
 551                 return (BUS_PROBE_LOW_PRIORITY);
 552         }
 553         return (result);
 554 }
 555
 556 static int
 557 attimer_attach(device_t dev)
 558 {
 559         struct attimer_softc *sc;
 560         rman_res_t s;
 561         int i;
 562
 563         attimer_sc = sc = device_get_softc(dev);
 564         bzero(sc, sizeof(struct attimer_softc));
 565         if (!(sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT,
 566             &sc->port_rid, IO_TIMER1, IO_TIMER1 + 3, 4, RF_ACTIVE)))
 567                 device_printf(dev,"Warning: Couldn't map I/O.\n");
 568         i8254_intsrc = intr_lookup_source(0);
 569         if (i8254_intsrc != NULL)
 570                 i8254_pending = i8254_intsrc->is_pic->pic_source_pending;
 571         resource_int_value(device_get_name(dev), device_get_unit(dev),
 572             "timecounter", &i8254_timecounter);
 573         set_i8254_freq(MODE_STOP, 0);
 574         if (i8254_timecounter) {
 575                 sc->tc.tc_get_timecount = i8254_get_timecount;
 576                 sc->tc.tc_counter_mask = 0xffff;
 577                 sc->tc.tc_frequency = i8254_freq;
 578                 sc->tc.tc_name = "i8254";
 579                 sc->tc.tc_quality = 0;
 580                 sc->tc.tc_priv = dev;
 581                 tc_init(&sc->tc);
 582         }
 583         if (resource_int_value(device_get_name(dev), device_get_unit(dev),
 584             "clock", &i) != 0 || i != 0) {
 585                 sc->intr_rid = 0;
 586                 while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid,
 587                     &s, NULL) == 0 && s != 0)
 588                         sc->intr_rid++;
 589                 if (!(sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
 590                     &sc->intr_rid, 0, 0, 1, RF_ACTIVE))) {
 591                         device_printf(dev,"Can't map interrupt.\n");
 592                         return (0);
 593                 }
 594                 /* Dirty hack, to make bus_setup_intr to not enable source. */
 595                 i8254_intsrc->is_handlers++;
 596                 if ((bus_setup_intr(dev, sc->intr_res,
 597                     INTR_MPSAFE | INTR_TYPE_CLK,
 598                     (driver_filter_t *)clkintr, NULL,
 599                     sc, &sc->intr_handler))) {
 600                         device_printf(dev, "Can't setup interrupt.\n");
 601                         i8254_intsrc->is_handlers--;
 602                         return (0);
 603                 }
 604                 i8254_intsrc->is_handlers--;
 605                 i8254_intsrc->is_pic->pic_enable_intr(i8254_intsrc);
 606                 sc->et.et_name = "i8254";
 607                 sc->et.et_flags = ET_FLAGS_PERIODIC;
 608                 if (!i8254_timecounter)
 609                         sc->et.et_flags |= ET_FLAGS_ONESHOT;
 610                 sc->et.et_quality = 100;
 611                 sc->et.et_frequency = i8254_freq;
 612                 sc->et.et_min_period = (0x0002LLU << 32) / i8254_freq;
 613                 sc->et.et_max_period = (0xfffeLLU << 32) / i8254_freq;
 614                 sc->et.et_start = attimer_start;
 615                 sc->et.et_stop = attimer_stop;
 616                 sc->et.et_priv = dev;
 617                 et_register(&sc->et);
 618         }
 619         return(0);
 620 }
 621
 622 static int
 623 attimer_resume(device_t dev)
 624 {
 625
 626         i8254_restore();
 627         return (0);
 628 }
 629
 630 static device_method_t attimer_methods[] = {
 631         /* Device interface */
 632         DEVMETHOD(device_probe,         attimer_probe),
 633         DEVMETHOD(device_attach,        attimer_attach),
 634         DEVMETHOD(device_detach,        bus_generic_detach),
 635         DEVMETHOD(device_shutdown,      bus_generic_shutdown),
 636         DEVMETHOD(device_suspend,       bus_generic_suspend),
 637         DEVMETHOD(device_resume,        attimer_resume),
 638         { 0, 0 }
 639 };
 640
 641 static driver_t attimer_driver = {
 642         "attimer",
 643         attimer_methods,
 644         sizeof(struct attimer_softc),
 645 };
 646
 647 static devclass_t attimer_devclass;
 648
 649 DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
 650 DRIVER_MODULE(attimer, acpi, attimer_driver, attimer_devclass, 0, 0);
 651 ISA_PNP_INFO(attimer_ids);
 652
 653 #endif /* DEV_ISA */