clock.c

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    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 #ifdef __amd64__
   46 #define DEV_APIC
   47 #else
   48 #include "opt_apic.h"
   49 #endif
   50 #include "opt_clock.h"
   51 #include "opt_isa.h"
   52 
   53 #include <sys/param.h>
   54 #include <sys/systm.h>
   55 #include <sys/bus.h>
   56 #include <sys/lock.h>
   57 #include <sys/kdb.h>
   58 #include <sys/mutex.h>
   59 #include <sys/proc.h>
   60 #include <sys/kernel.h>
   61 #include <sys/module.h>
   62 #include <sys/rman.h>
   63 #include <sys/sched.h>
   64 #include <sys/smp.h>
   65 #include <sys/sysctl.h>
   66 #include <sys/timeet.h>
   67 #include <sys/timetc.h>
   68 
   69 #include <machine/clock.h>
   70 #include <machine/cpu.h>
   71 #include <machine/intr_machdep.h>
   72 #include <machine/ppireg.h>
   73 #include <machine/timerreg.h>
   74 #include <x86/apicvar.h>
   75 #include <x86/init.h>
   76 
   77 #include <isa/rtc.h>
   78 #ifdef DEV_ISA
   79 #include <isa/isareg.h>
   80 #include <isa/isavar.h>
   81 #endif
   82 
   83 int     clkintr_pending;
   84 #ifndef TIMER_FREQ
   85 #define TIMER_FREQ   1193182
   86 #endif
   87 u_int   i8254_freq = TIMER_FREQ;
   88 TUNABLE_INT("hw.i8254.freq", &i8254_freq);
   89 int     i8254_max_count;
   90 static int i8254_timecounter = 1;
   91 
   92 static  struct mtx clock_lock;
   93 static  struct intsrc *i8254_intsrc;
   94 static  uint16_t i8254_lastcount;
   95 static  uint16_t i8254_offset;
   96 static  int     (*i8254_pending)(struct intsrc *);
   97 static  int     i8254_ticked;
   98 
   99 struct attimer_softc {
  100         int intr_en;
  101         int port_rid, intr_rid;
  102         struct resource *port_res;
  103         struct resource *intr_res;
  104         void *intr_handler;
  105         struct timecounter tc;
  106         struct eventtimer et;
  107         int             mode;
  108 #define MODE_STOP       0
  109 #define MODE_PERIODIC   1
  110 #define MODE_ONESHOT    2
  111         uint32_t        period;
  112 };
  113 static struct attimer_softc *attimer_sc = NULL;
  114 
  115 static int timer0_period = -2;
  116 static int timer0_mode = 0xffff;
  117 static int timer0_last = 0xffff;
  118 
  119 /* Values for timerX_state: */
  120 #define RELEASED        0
  121 #define RELEASE_PENDING 1
  122 #define ACQUIRED        2
  123 #define ACQUIRE_PENDING 3
  124 
  125 static  u_char  timer2_state;
  126 
  127 static  unsigned i8254_get_timecount(struct timecounter *tc);
  128 static  void    set_i8254_freq(int mode, uint32_t period);
  129 
  130 void
  131 clock_init(void)
  132 {
  133         /* Init the clock lock */
  134         mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_NOPROFILE);
  135         /* Init the clock in order to use DELAY */
  136         init_ops.early_clock_source_init();
  137         tsc_init();
  138 }
  139 
  140 static int
  141 clkintr(void *arg)
  142 {
  143         struct attimer_softc *sc = (struct attimer_softc *)arg;
  144 
  145         if (i8254_timecounter && sc->period != 0) {
  146                 mtx_lock_spin(&clock_lock);
  147                 if (i8254_ticked)
  148                         i8254_ticked = 0;
  149                 else {
  150                         i8254_offset += i8254_max_count;
  151                         i8254_lastcount = 0;
  152                 }
  153                 clkintr_pending = 0;
  154                 mtx_unlock_spin(&clock_lock);
  155         }
  156 
  157         if (sc->et.et_active && sc->mode != MODE_STOP)
  158                 sc->et.et_event_cb(&sc->et, sc->et.et_arg);
  159 
  160         return (FILTER_HANDLED);
  161 }
  162 
  163 int
  164 timer_spkr_acquire(void)
  165 {
  166         int mode;
  167 
  168         mode = TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT;
  169 
  170         if (timer2_state != RELEASED)
  171                 return (-1);
  172         timer2_state = ACQUIRED;
  173 
  174         /*
  175          * This access to the timer registers is as atomic as possible
  176          * because it is a single instruction.  We could do better if we
  177          * knew the rate.  Use of splclock() limits glitches to 10-100us,
  178          * and this is probably good enough for timer2, so we aren't as
  179          * careful with it as with timer0.
  180          */
  181         outb(TIMER_MODE, TIMER_SEL2 | (mode & 0x3f));
  182 
  183         ppi_spkr_on();          /* enable counter2 output to speaker */
  184         return (0);
  185 }
  186 
  187 int
  188 timer_spkr_release(void)
  189 {
  190 
  191         if (timer2_state != ACQUIRED)
  192                 return (-1);
  193         timer2_state = RELEASED;
  194         outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
  195 
  196         ppi_spkr_off();         /* disable counter2 output to speaker */
  197         return (0);
  198 }
  199 
  200 void
  201 timer_spkr_setfreq(int freq)
  202 {
  203 
  204         freq = i8254_freq / freq;
  205         mtx_lock_spin(&clock_lock);
  206         outb(TIMER_CNTR2, freq & 0xff);
  207         outb(TIMER_CNTR2, freq >> 8);
  208         mtx_unlock_spin(&clock_lock);
  209 }
  210 
  211 static int
  212 getit(void)
  213 {
  214         int high, low;
  215 
  216         mtx_lock_spin(&clock_lock);
  217 
  218         /* Select timer0 and latch counter value. */
  219         outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
  220 
  221         low = inb(TIMER_CNTR0);
  222         high = inb(TIMER_CNTR0);
  223 
  224         mtx_unlock_spin(&clock_lock);
  225         return ((high << 8) | low);
  226 }
  227 
  228 /*
  229  * Wait "n" microseconds.
  230  * Relies on timer 1 counting down from (i8254_freq / hz)
  231  * Note: timer had better have been programmed before this is first used!
  232  */
  233 void
  234 i8254_delay(int n)
  235 {
  236         int delta, prev_tick, tick, ticks_left;
  237 #ifdef DELAYDEBUG
  238         int getit_calls = 1;
  239         int n1;
  240         static int state = 0;
  241 
  242         if (state == 0) {
  243                 state = 1;
  244                 for (n1 = 1; n1 <= 10000000; n1 *= 10)
  245                         DELAY(n1);
  246                 state = 2;
  247         }
  248         if (state == 1)
  249                 printf("DELAY(%d)...", n);
  250 #endif
  251         /*
  252          * Read the counter first, so that the rest of the setup overhead is
  253          * counted.  Guess the initial overhead is 20 usec (on most systems it
  254          * takes about 1.5 usec for each of the i/o's in getit().  The loop
  255          * takes about 6 usec on a 486/33 and 13 usec on a 386/20.  The
  256          * multiplications and divisions to scale the count take a while).
  257          *
  258          * However, if ddb is active then use a fake counter since reading
  259          * the i8254 counter involves acquiring a lock.  ddb must not do
  260          * locking for many reasons, but it calls here for at least atkbd
  261          * input.
  262          */
  263 #ifdef KDB
  264         if (kdb_active)
  265                 prev_tick = 1;
  266         else
  267 #endif
  268                 prev_tick = getit();
  269         n -= 0;                 /* XXX actually guess no initial overhead */
  270         /*
  271          * Calculate (n * (i8254_freq / 1e6)) without using floating point
  272          * and without any avoidable overflows.
  273          */
  274         if (n <= 0)
  275                 ticks_left = 0;
  276         else if (n < 256)
  277                 /*
  278                  * Use fixed point to avoid a slow division by 1000000.
  279                  * 39099 = 1193182 * 2^15 / 10^6 rounded to nearest.
  280                  * 2^15 is the first power of 2 that gives exact results
  281                  * for n between 0 and 256.
  282                  */
  283                 ticks_left = ((u_int)n * 39099 + (1 << 15) - 1) >> 15;
  284         else
  285                 /*
  286                  * Don't bother using fixed point, although gcc-2.7.2
  287                  * generates particularly poor code for the long long
  288                  * division, since even the slow way will complete long
  289                  * before the delay is up (unless we're interrupted).
  290                  */
  291                 ticks_left = ((u_int)n * (long long)i8254_freq + 999999)
  292                              / 1000000;
  293 
  294         while (ticks_left > 0) {
  295 #ifdef KDB
  296                 if (kdb_active) {
  297                         inb(0x84);
  298                         tick = prev_tick - 1;
  299                         if (tick <= 0)
  300                                 tick = i8254_max_count;
  301                 } else
  302 #endif
  303                         tick = getit();
  304 #ifdef DELAYDEBUG
  305                 ++getit_calls;
  306 #endif
  307                 delta = prev_tick - tick;
  308                 prev_tick = tick;
  309                 if (delta < 0) {
  310                         delta += i8254_max_count;
  311                         /*
  312                          * Guard against i8254_max_count being wrong.
  313                          * This shouldn't happen in normal operation,
  314                          * but it may happen if set_i8254_freq() is
  315                          * traced.
  316                          */
  317                         if (delta < 0)
  318                                 delta = 0;
  319                 }
  320                 ticks_left -= delta;
  321         }
  322 #ifdef DELAYDEBUG
  323         if (state == 1)
  324                 printf(" %d calls to getit() at %d usec each\n",
  325                        getit_calls, (n + 5) / getit_calls);
  326 #endif
  327 }
  328 
  329 static void
  330 set_i8254_freq(int mode, uint32_t period)
  331 {
  332         int new_count, new_mode;
  333 
  334         mtx_lock_spin(&clock_lock);
  335         if (mode == MODE_STOP) {
  336                 if (i8254_timecounter) {
  337                         mode = MODE_PERIODIC;
  338                         new_count = 0x10000;
  339                 } else
  340                         new_count = -1;
  341         } else {
  342                 new_count = min(((uint64_t)i8254_freq * period +
  343                     0x80000000LLU) >> 32, 0x10000);
  344         }
  345         if (new_count == timer0_period)
  346                 goto out;
  347         i8254_max_count = ((new_count & ~0xffff) != 0) ? 0xffff : new_count;
  348         timer0_period = (mode == MODE_PERIODIC) ? new_count : -1;
  349         switch (mode) {
  350         case MODE_STOP:
  351                 new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_16BIT;
  352                 outb(TIMER_MODE, new_mode);
  353                 outb(TIMER_CNTR0, 0);
  354                 outb(TIMER_CNTR0, 0);
  355                 break;
  356         case MODE_PERIODIC:
  357                 new_mode = TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT;
  358                 outb(TIMER_MODE, new_mode);
  359                 outb(TIMER_CNTR0, new_count & 0xff);
  360                 outb(TIMER_CNTR0, new_count >> 8);
  361                 break;
  362         case MODE_ONESHOT:
  363                 if (new_count < 256 && timer0_last < 256) {
  364                         new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_LSB;
  365                         if (new_mode != timer0_mode)
  366                                 outb(TIMER_MODE, new_mode);
  367                         outb(TIMER_CNTR0, new_count & 0xff);
  368                         break;
  369                 }
  370                 new_mode = TIMER_SEL0 | TIMER_INTTC | TIMER_16BIT;
  371                 if (new_mode != timer0_mode)
  372                         outb(TIMER_MODE, new_mode);
  373                 outb(TIMER_CNTR0, new_count & 0xff);
  374                 outb(TIMER_CNTR0, new_count >> 8);
  375                 break;
  376         default:
  377                 panic("set_i8254_freq: unknown operational mode");
  378         }
  379         timer0_mode = new_mode;
  380         timer0_last = new_count;
  381 out:
  382         mtx_unlock_spin(&clock_lock);
  383 }
  384 
  385 static void
  386 i8254_restore(void)
  387 {
  388 
  389         timer0_period = -2;
  390         timer0_mode = 0xffff;
  391         timer0_last = 0xffff;
  392         if (attimer_sc != NULL)
  393                 set_i8254_freq(attimer_sc->mode, attimer_sc->period);
  394         else
  395                 set_i8254_freq(MODE_STOP, 0);
  396 }
  397 
  398 /* This is separate from startrtclock() so that it can be called early. */
  399 void
  400 i8254_init(void)
  401 {
  402 
  403         set_i8254_freq(MODE_STOP, 0);
  404 }
  405 
  406 void
  407 startrtclock(void)
  408 {
  409 
  410         start_TSC();
  411 }
  412 
  413 void
  414 cpu_initclocks(void)
  415 {
  416 #ifdef EARLY_AP_STARTUP
  417         struct thread *td;
  418         int i;
  419 
  420         td = curthread;
  421 
  422         tsc_calibrate();
  423 #ifdef DEV_APIC
  424         lapic_calibrate_timer();
  425 #endif
  426         cpu_initclocks_bsp();
  427         CPU_FOREACH(i) {
  428                 if (i == 0)
  429                         continue;
  430                 thread_lock(td);
  431                 sched_bind(td, i);
  432                 thread_unlock(td);
  433                 cpu_initclocks_ap();
  434         }
  435         thread_lock(td);
  436         if (sched_is_bound(td))
  437                 sched_unbind(td);
  438         thread_unlock(td);
  439 #else
  440         tsc_calibrate();
  441 #ifdef DEV_APIC
  442         lapic_calibrate_timer();
  443 #endif
  444         cpu_initclocks_bsp();
  445 #endif
  446 }
  447 
  448 static int
  449 sysctl_machdep_i8254_freq(SYSCTL_HANDLER_ARGS)
  450 {
  451         int error;
  452         u_int freq;
  453 
  454         /*
  455          * Use `i8254' instead of `timer' in external names because `timer'
  456          * is too generic.  Should use it everywhere.
  457          */
  458         freq = i8254_freq;
  459         error = sysctl_handle_int(oidp, &freq, 0, req);
  460         if (error == 0 && req->newptr != NULL) {
  461                 i8254_freq = freq;
  462                 if (attimer_sc != NULL) {
  463                         set_i8254_freq(attimer_sc->mode, attimer_sc->period);
  464                         attimer_sc->tc.tc_frequency = freq;
  465                 } else {
  466                         set_i8254_freq(MODE_STOP, 0);
  467                 }
  468         }
  469         return (error);
  470 }
  471 
  472 SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq,
  473     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
  474     0, sizeof(u_int), sysctl_machdep_i8254_freq, "IU",
  475     "i8254 timer frequency");
  476 
  477 static unsigned
  478 i8254_get_timecount(struct timecounter *tc)
  479 {
  480         device_t dev = (device_t)tc->tc_priv;
  481         struct attimer_softc *sc = device_get_softc(dev);
  482         register_t flags;
  483         uint16_t count;
  484         u_int high, low;
  485 
  486         if (sc->period == 0)
  487                 return (i8254_max_count - getit());
  488 
  489 #ifdef __amd64__
  490         flags = read_rflags();
  491 #else
  492         flags = read_eflags();
  493 #endif
  494         mtx_lock_spin(&clock_lock);
  495 
  496         /* Select timer0 and latch counter value. */
  497         outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
  498 
  499         low = inb(TIMER_CNTR0);
  500         high = inb(TIMER_CNTR0);
  501         count = i8254_max_count - ((high << 8) | low);
  502         if (count < i8254_lastcount ||
  503             (!i8254_ticked && (clkintr_pending ||
  504             ((count < 20 || (!(flags & PSL_I) &&
  505             count < i8254_max_count / 2u)) &&
  506             i8254_pending != NULL && i8254_pending(i8254_intsrc))))) {
  507                 i8254_ticked = 1;
  508                 i8254_offset += i8254_max_count;
  509         }
  510         i8254_lastcount = count;
  511         count += i8254_offset;
  512         mtx_unlock_spin(&clock_lock);
  513         return (count);
  514 }
  515 
  516 static int
  517 attimer_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
  518 {
  519         device_t dev = (device_t)et->et_priv;
  520         struct attimer_softc *sc = device_get_softc(dev);
  521 
  522         if (period != 0) {
  523                 sc->mode = MODE_PERIODIC;
  524                 sc->period = period;
  525         } else {
  526                 sc->mode = MODE_ONESHOT;
  527                 sc->period = first;
  528         }
  529         if (!sc->intr_en) {
  530                 i8254_intsrc->is_pic->pic_enable_source(i8254_intsrc);
  531                 sc->intr_en = 1;
  532         }
  533         set_i8254_freq(sc->mode, sc->period);
  534         return (0);
  535 }
  536 
  537 static int
  538 attimer_stop(struct eventtimer *et)
  539 {
  540         device_t dev = (device_t)et->et_priv;
  541         struct attimer_softc *sc = device_get_softc(dev);
  542 
  543         sc->mode = MODE_STOP;
  544         sc->period = 0;
  545         set_i8254_freq(sc->mode, sc->period);
  546         return (0);
  547 }
  548 
  549 #ifdef DEV_ISA
  550 /*
  551  * Attach to the ISA PnP descriptors for the timer
  552  */
  553 static struct isa_pnp_id attimer_ids[] = {
  554         { 0x0001d041 /* PNP0100 */, "AT timer" },
  555         { 0 }
  556 };
  557 
  558 static int
  559 attimer_probe(device_t dev)
  560 {
  561         int result;
  562 
  563         result = ISA_PNP_PROBE(device_get_parent(dev), dev, attimer_ids);
  564         /* ENOENT means no PnP-ID, device is hinted. */
  565         if (result == ENOENT) {
  566                 device_set_desc(dev, "AT timer");
  567                 return (BUS_PROBE_LOW_PRIORITY);
  568         }
  569         return (result);
  570 }
  571 
  572 static int
  573 attimer_attach(device_t dev)
  574 {
  575         struct attimer_softc *sc;
  576         rman_res_t s;
  577         int i;
  578 
  579         attimer_sc = sc = device_get_softc(dev);
  580         bzero(sc, sizeof(struct attimer_softc));
  581         if (!(sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT,
  582             &sc->port_rid, IO_TIMER1, IO_TIMER1 + 3, 4, RF_ACTIVE)))
  583                 device_printf(dev,"Warning: Couldn't map I/O.\n");
  584         i8254_intsrc = intr_lookup_source(0);
  585         if (i8254_intsrc != NULL)
  586                 i8254_pending = i8254_intsrc->is_pic->pic_source_pending;
  587         resource_int_value(device_get_name(dev), device_get_unit(dev),
  588             "timecounter", &i8254_timecounter);
  589         set_i8254_freq(MODE_STOP, 0);
  590         if (i8254_timecounter) {
  591                 sc->tc.tc_get_timecount = i8254_get_timecount;
  592                 sc->tc.tc_counter_mask = 0xffff;
  593                 sc->tc.tc_frequency = i8254_freq;
  594                 sc->tc.tc_name = "i8254";
  595                 sc->tc.tc_quality = 0;
  596                 sc->tc.tc_priv = dev;
  597                 tc_init(&sc->tc);
  598         }
  599         if (resource_int_value(device_get_name(dev), device_get_unit(dev),
  600             "clock", &i) != 0 || i != 0) {
  601                 sc->intr_rid = 0;
  602                 while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid,
  603                     &s, NULL) == 0 && s != 0)
  604                         sc->intr_rid++;
  605                 if (!(sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
  606                     &sc->intr_rid, 0, 0, 1, RF_ACTIVE))) {
  607                         device_printf(dev,"Can't map interrupt.\n");
  608                         return (0);
  609                 }
  610                 /* Dirty hack, to make bus_setup_intr to not enable source. */
  611                 i8254_intsrc->is_handlers++;
  612                 if ((bus_setup_intr(dev, sc->intr_res,
  613                     INTR_MPSAFE | INTR_TYPE_CLK,
  614                     (driver_filter_t *)clkintr, NULL,
  615                     sc, &sc->intr_handler))) {
  616                         device_printf(dev, "Can't setup interrupt.\n");
  617                         i8254_intsrc->is_handlers--;
  618                         return (0);
  619                 }
  620                 i8254_intsrc->is_handlers--;
  621                 i8254_intsrc->is_pic->pic_enable_intr(i8254_intsrc);
  622                 sc->et.et_name = "i8254";
  623                 sc->et.et_flags = ET_FLAGS_PERIODIC;
  624                 if (!i8254_timecounter)
  625                         sc->et.et_flags |= ET_FLAGS_ONESHOT;
  626                 sc->et.et_quality = 100;
  627                 sc->et.et_frequency = i8254_freq;
  628                 sc->et.et_min_period = (0x0002LLU << 32) / i8254_freq;
  629                 sc->et.et_max_period = (0xfffeLLU << 32) / i8254_freq;
  630                 sc->et.et_start = attimer_start;
  631                 sc->et.et_stop = attimer_stop;
  632                 sc->et.et_priv = dev;
  633                 et_register(&sc->et);
  634         }
  635         return(0);
  636 }
  637 
  638 static int
  639 attimer_resume(device_t dev)
  640 {
  641 
  642         i8254_restore();
  643         return (0);
  644 }
  645 
  646 static device_method_t attimer_methods[] = {
  647         /* Device interface */
  648         DEVMETHOD(device_probe,         attimer_probe),
  649         DEVMETHOD(device_attach,        attimer_attach),
  650         DEVMETHOD(device_detach,        bus_generic_detach),
  651         DEVMETHOD(device_shutdown,      bus_generic_shutdown),
  652         DEVMETHOD(device_suspend,       bus_generic_suspend),
  653         DEVMETHOD(device_resume,        attimer_resume),
  654         { 0, 0 }
  655 };
  656 
  657 static driver_t attimer_driver = {
  658         "attimer",
  659         attimer_methods,
  660         sizeof(struct attimer_softc),
  661 };
  662 
  663 DRIVER_MODULE(attimer, isa, attimer_driver, 0, 0);
  664 DRIVER_MODULE(attimer, acpi, attimer_driver, 0, 0);
  665 ISA_PNP_INFO(attimer_ids);
  666 
  667 #endif /* DEV_ISA */
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FreeBSD/Linux Kernel Cross Reference sys/x86/isa/clock.c

FreeBSD/Linux Kernel Cross Reference
sys/x86/isa/clock.c
