1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2008 Poul-Henning Kamp 5 * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org> 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 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_acpi.h" 36 #include "opt_isa.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bus.h> 41 #include <sys/clock.h> 42 #include <sys/lock.h> 43 #include <sys/mutex.h> 44 #include <sys/kdb.h> 45 #include <sys/kernel.h> 46 #include <sys/module.h> 47 #include <sys/proc.h> 48 #include <sys/rman.h> 49 #include <sys/timeet.h> 50 51 #include <isa/rtc.h> 52 #ifdef DEV_ISA 53 #include <isa/isareg.h> 54 #include <isa/isavar.h> 55 #endif 56 #include <machine/intr_machdep.h> 57 #include "clock_if.h" 58 #ifdef DEV_ACPI 59 #include <contrib/dev/acpica/include/acpi.h> 60 #include <contrib/dev/acpica/include/accommon.h> 61 #include <dev/acpica/acpivar.h> 62 #include <machine/md_var.h> 63 #endif 64 65 /* 66 * atrtc_lock protects low-level access to individual hardware registers. 67 * atrtc_time_lock protects the entire sequence of accessing multiple registers 68 * to read or write the date and time. 69 */ 70 static struct mtx atrtc_lock; 71 MTX_SYSINIT(atrtc_lock_init, &atrtc_lock, "atrtc", MTX_SPIN); 72 73 /* Force RTC enabled/disabled. */ 74 static int atrtc_enabled = -1; 75 TUNABLE_INT("hw.atrtc.enabled", &atrtc_enabled); 76 77 struct mtx atrtc_time_lock; 78 MTX_SYSINIT(atrtc_time_lock_init, &atrtc_time_lock, "atrtc_time", MTX_DEF); 79 80 int atrtcclock_disable = 0; 81 82 static int rtc_century = 0; 83 static int rtc_reg = -1; 84 static u_char rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF; 85 static u_char rtc_statusb = RTCSB_24HR; 86 87 #ifdef DEV_ACPI 88 #define _COMPONENT ACPI_TIMER 89 ACPI_MODULE_NAME("ATRTC") 90 #endif 91 92 /* 93 * RTC support routines 94 */ 95 96 static inline u_char 97 rtcin_locked(int reg) 98 { 99 100 if (rtc_reg != reg) { 101 inb(0x84); 102 outb(IO_RTC, reg); 103 rtc_reg = reg; 104 inb(0x84); 105 } 106 return (inb(IO_RTC + 1)); 107 } 108 109 static inline void 110 rtcout_locked(int reg, u_char val) 111 { 112 113 if (rtc_reg != reg) { 114 inb(0x84); 115 outb(IO_RTC, reg); 116 rtc_reg = reg; 117 inb(0x84); 118 } 119 outb(IO_RTC + 1, val); 120 inb(0x84); 121 } 122 123 int 124 rtcin(int reg) 125 { 126 u_char val; 127 128 mtx_lock_spin(&atrtc_lock); 129 val = rtcin_locked(reg); 130 mtx_unlock_spin(&atrtc_lock); 131 return (val); 132 } 133 134 void 135 writertc(int reg, u_char val) 136 { 137 138 mtx_lock_spin(&atrtc_lock); 139 rtcout_locked(reg, val); 140 mtx_unlock_spin(&atrtc_lock); 141 } 142 143 static void 144 atrtc_start(void) 145 { 146 147 mtx_lock_spin(&atrtc_lock); 148 rtcout_locked(RTC_STATUSA, rtc_statusa); 149 rtcout_locked(RTC_STATUSB, RTCSB_24HR); 150 mtx_unlock_spin(&atrtc_lock); 151 } 152 153 static void 154 atrtc_rate(unsigned rate) 155 { 156 157 rtc_statusa = RTCSA_DIVIDER | rate; 158 writertc(RTC_STATUSA, rtc_statusa); 159 } 160 161 static void 162 atrtc_enable_intr(void) 163 { 164 165 rtc_statusb |= RTCSB_PINTR; 166 mtx_lock_spin(&atrtc_lock); 167 rtcout_locked(RTC_STATUSB, rtc_statusb); 168 rtcin_locked(RTC_INTR); 169 mtx_unlock_spin(&atrtc_lock); 170 } 171 172 static void 173 atrtc_disable_intr(void) 174 { 175 176 rtc_statusb &= ~RTCSB_PINTR; 177 mtx_lock_spin(&atrtc_lock); 178 rtcout_locked(RTC_STATUSB, rtc_statusb); 179 rtcin_locked(RTC_INTR); 180 mtx_unlock_spin(&atrtc_lock); 181 } 182 183 void 184 atrtc_restore(void) 185 { 186 187 /* Restore all of the RTC's "status" (actually, control) registers. */ 188 mtx_lock_spin(&atrtc_lock); 189 rtcin_locked(RTC_STATUSA); /* dummy to get rtc_reg set */ 190 rtcout_locked(RTC_STATUSB, RTCSB_24HR); 191 rtcout_locked(RTC_STATUSA, rtc_statusa); 192 rtcout_locked(RTC_STATUSB, rtc_statusb); 193 rtcin_locked(RTC_INTR); 194 mtx_unlock_spin(&atrtc_lock); 195 } 196 197 /********************************************************************** 198 * RTC driver for subr_rtc 199 */ 200 201 struct atrtc_softc { 202 int port_rid, intr_rid; 203 struct resource *port_res; 204 struct resource *intr_res; 205 void *intr_handler; 206 struct eventtimer et; 207 #ifdef DEV_ACPI 208 ACPI_HANDLE acpi_handle; 209 #endif 210 }; 211 212 static int 213 rtc_start(struct eventtimer *et, sbintime_t first, sbintime_t period) 214 { 215 216 atrtc_rate(max(fls(period + (period >> 1)) - 17, 1)); 217 atrtc_enable_intr(); 218 return (0); 219 } 220 221 static int 222 rtc_stop(struct eventtimer *et) 223 { 224 225 atrtc_disable_intr(); 226 return (0); 227 } 228 229 /* 230 * This routine receives statistical clock interrupts from the RTC. 231 * As explained above, these occur at 128 interrupts per second. 232 * When profiling, we receive interrupts at a rate of 1024 Hz. 233 * 234 * This does not actually add as much overhead as it sounds, because 235 * when the statistical clock is active, the hardclock driver no longer 236 * needs to keep (inaccurate) statistics on its own. This decouples 237 * statistics gathering from scheduling interrupts. 238 * 239 * The RTC chip requires that we read status register C (RTC_INTR) 240 * to acknowledge an interrupt, before it will generate the next one. 241 * Under high interrupt load, rtcintr() can be indefinitely delayed and 242 * the clock can tick immediately after the read from RTC_INTR. In this 243 * case, the mc146818A interrupt signal will not drop for long enough 244 * to register with the 8259 PIC. If an interrupt is missed, the stat 245 * clock will halt, considerably degrading system performance. This is 246 * why we use 'while' rather than a more straightforward 'if' below. 247 * Stat clock ticks can still be lost, causing minor loss of accuracy 248 * in the statistics, but the stat clock will no longer stop. 249 */ 250 static int 251 rtc_intr(void *arg) 252 { 253 struct atrtc_softc *sc = (struct atrtc_softc *)arg; 254 int flag = 0; 255 256 while (rtcin(RTC_INTR) & RTCIR_PERIOD) { 257 flag = 1; 258 if (sc->et.et_active) 259 sc->et.et_event_cb(&sc->et, sc->et.et_arg); 260 } 261 return(flag ? FILTER_HANDLED : FILTER_STRAY); 262 } 263 264 #ifdef DEV_ACPI 265 /* 266 * ACPI RTC CMOS address space handler 267 */ 268 #define ATRTC_LAST_REG 0x40 269 270 static void 271 rtcin_region(int reg, void *buf, int len) 272 { 273 u_char *ptr = buf; 274 275 /* Drop lock after each IO as intr and settime have greater priority */ 276 while (len-- > 0) 277 *ptr++ = rtcin(reg++) & 0xff; 278 } 279 280 static void 281 rtcout_region(int reg, const void *buf, int len) 282 { 283 const u_char *ptr = buf; 284 285 while (len-- > 0) 286 writertc(reg++, *ptr++); 287 } 288 289 static bool 290 atrtc_check_cmos_access(bool is_read, ACPI_PHYSICAL_ADDRESS addr, UINT32 len) 291 { 292 293 /* Block address space wrapping on out-of-bound access */ 294 if (addr >= ATRTC_LAST_REG || addr + len > ATRTC_LAST_REG) 295 return (false); 296 297 if (is_read) { 298 /* Reading 0x0C will muck with interrupts */ 299 if (addr <= RTC_INTR && addr + len > RTC_INTR) 300 return (false); 301 } else { 302 /* 303 * Allow single-byte writes to alarm registers and 304 * multi-byte writes to addr >= 0x30, else deny. 305 */ 306 if (!((len == 1 && (addr == RTC_SECALRM || 307 addr == RTC_MINALRM || 308 addr == RTC_HRSALRM)) || 309 addr >= 0x30)) 310 return (false); 311 } 312 return (true); 313 } 314 315 static ACPI_STATUS 316 atrtc_acpi_cmos_handler(UINT32 func, ACPI_PHYSICAL_ADDRESS addr, 317 UINT32 bitwidth, UINT64 *value, void *context, void *region_context) 318 { 319 device_t dev = context; 320 UINT32 bytewidth = howmany(bitwidth, 8); 321 bool is_read = func == ACPI_READ; 322 323 /* ACPICA is very verbose on CMOS handler failures, so we, too */ 324 #define CMOS_HANDLER_ERR(fmt, ...) \ 325 device_printf(dev, "ACPI [SystemCMOS] handler: " fmt, ##__VA_ARGS__) 326 327 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 328 329 if (value == NULL) { 330 CMOS_HANDLER_ERR("NULL parameter\n"); 331 return (AE_BAD_PARAMETER); 332 } 333 if (bitwidth == 0 || (bitwidth & 0x07) != 0) { 334 CMOS_HANDLER_ERR("Invalid bitwidth: %u\n", bitwidth); 335 return (AE_BAD_PARAMETER); 336 } 337 if (!atrtc_check_cmos_access(is_read, addr, bytewidth)) { 338 CMOS_HANDLER_ERR("%s access rejected: addr=%#04jx, len=%u\n", 339 is_read ? "Read" : "Write", (uintmax_t)addr, bytewidth); 340 return (AE_BAD_PARAMETER); 341 } 342 343 switch (func) { 344 case ACPI_READ: 345 rtcin_region(addr, value, bytewidth); 346 break; 347 case ACPI_WRITE: 348 rtcout_region(addr, value, bytewidth); 349 break; 350 default: 351 CMOS_HANDLER_ERR("Invalid function: %u\n", func); 352 return (AE_BAD_PARAMETER); 353 } 354 355 ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev), 356 "ACPI RTC CMOS %s access: addr=%#04x, len=%u, val=%*D\n", 357 is_read ? "read" : "write", (unsigned)addr, bytewidth, 358 bytewidth, value, " "); 359 360 return (AE_OK); 361 } 362 363 static int 364 atrtc_reg_acpi_cmos_handler(device_t dev) 365 { 366 struct atrtc_softc *sc = device_get_softc(dev); 367 368 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 369 370 /* Don't handle address space events if driver is disabled. */ 371 if (acpi_disabled("atrtc")) 372 return (ENXIO); 373 374 sc->acpi_handle = acpi_get_handle(dev); 375 if (sc->acpi_handle == NULL || 376 ACPI_FAILURE(AcpiInstallAddressSpaceHandler(sc->acpi_handle, 377 ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler, NULL, dev))) { 378 sc->acpi_handle = NULL; 379 device_printf(dev, 380 "Can't register ACPI CMOS address space handler\n"); 381 return (ENXIO); 382 } 383 384 return (0); 385 } 386 387 static int 388 atrtc_unreg_acpi_cmos_handler(device_t dev) 389 { 390 struct atrtc_softc *sc = device_get_softc(dev); 391 392 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); 393 394 if (sc->acpi_handle != NULL) 395 AcpiRemoveAddressSpaceHandler(sc->acpi_handle, 396 ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler); 397 398 return (0); 399 } 400 #endif /* DEV_ACPI */ 401 402 /* 403 * Attach to the ISA PnP descriptors for the timer and realtime clock. 404 */ 405 static struct isa_pnp_id atrtc_ids[] = { 406 { 0x000bd041 /* PNP0B00 */, "AT realtime clock" }, 407 { 0 } 408 }; 409 410 static bool 411 atrtc_acpi_disabled(void) 412 { 413 #ifdef DEV_ACPI 414 uint16_t flags; 415 416 if (!acpi_get_fadt_bootflags(&flags)) 417 return (false); 418 return ((flags & ACPI_FADT_NO_CMOS_RTC) != 0); 419 #else 420 return (false); 421 #endif 422 } 423 424 static int 425 rtc_acpi_century_get(void) 426 { 427 #ifdef DEV_ACPI 428 ACPI_TABLE_FADT *fadt; 429 vm_paddr_t physaddr; 430 int century; 431 432 physaddr = acpi_find_table(ACPI_SIG_FADT); 433 if (physaddr == 0) 434 return (0); 435 436 fadt = acpi_map_table(physaddr, ACPI_SIG_FADT); 437 if (fadt == NULL) 438 return (0); 439 440 century = fadt->Century; 441 acpi_unmap_table(fadt); 442 443 return (century); 444 #else 445 return (0); 446 #endif 447 } 448 449 static int 450 atrtc_probe(device_t dev) 451 { 452 int result; 453 454 if ((atrtc_enabled == -1 && atrtc_acpi_disabled()) || 455 (atrtc_enabled == 0)) 456 return (ENXIO); 457 458 result = ISA_PNP_PROBE(device_get_parent(dev), dev, atrtc_ids); 459 /* ENOENT means no PnP-ID, device is hinted. */ 460 if (result == ENOENT) { 461 device_set_desc(dev, "AT realtime clock"); 462 return (BUS_PROBE_LOW_PRIORITY); 463 } 464 rtc_century = rtc_acpi_century_get(); 465 return (result); 466 } 467 468 static int 469 atrtc_attach(device_t dev) 470 { 471 struct atrtc_softc *sc; 472 rman_res_t s; 473 int i; 474 475 sc = device_get_softc(dev); 476 sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->port_rid, 477 IO_RTC, IO_RTC + 1, 2, RF_ACTIVE); 478 if (sc->port_res == NULL) 479 device_printf(dev, "Warning: Couldn't map I/O.\n"); 480 atrtc_start(); 481 clock_register(dev, 1000000); 482 bzero(&sc->et, sizeof(struct eventtimer)); 483 if (!atrtcclock_disable && 484 (resource_int_value(device_get_name(dev), device_get_unit(dev), 485 "clock", &i) != 0 || i != 0)) { 486 sc->intr_rid = 0; 487 while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid, 488 &s, NULL) == 0 && s != 8) 489 sc->intr_rid++; 490 sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ, 491 &sc->intr_rid, 8, 8, 1, RF_ACTIVE); 492 if (sc->intr_res == NULL) { 493 device_printf(dev, "Can't map interrupt.\n"); 494 return (0); 495 } else if ((bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK, 496 rtc_intr, NULL, sc, &sc->intr_handler))) { 497 device_printf(dev, "Can't setup interrupt.\n"); 498 return (0); 499 } else { 500 /* Bind IRQ to BSP to avoid live migration. */ 501 bus_bind_intr(dev, sc->intr_res, 0); 502 } 503 sc->et.et_name = "RTC"; 504 sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_POW2DIV; 505 sc->et.et_quality = 0; 506 sc->et.et_frequency = 32768; 507 sc->et.et_min_period = 0x00080000; 508 sc->et.et_max_period = 0x80000000; 509 sc->et.et_start = rtc_start; 510 sc->et.et_stop = rtc_stop; 511 sc->et.et_priv = dev; 512 et_register(&sc->et); 513 } 514 return(0); 515 } 516 517 static int 518 atrtc_isa_attach(device_t dev) 519 { 520 521 return (atrtc_attach(dev)); 522 } 523 524 #ifdef DEV_ACPI 525 static int 526 atrtc_acpi_attach(device_t dev) 527 { 528 int ret; 529 530 ret = atrtc_attach(dev); 531 if (ret) 532 return (ret); 533 534 (void)atrtc_reg_acpi_cmos_handler(dev); 535 536 return (0); 537 } 538 539 static int 540 atrtc_acpi_detach(device_t dev) 541 { 542 543 (void)atrtc_unreg_acpi_cmos_handler(dev); 544 return (0); 545 } 546 #endif /* DEV_ACPI */ 547 548 static int 549 atrtc_resume(device_t dev) 550 { 551 552 atrtc_restore(); 553 return(0); 554 } 555 556 static int 557 atrtc_settime(device_t dev __unused, struct timespec *ts) 558 { 559 struct bcd_clocktime bct; 560 561 clock_ts_to_bcd(ts, &bct, false); 562 clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bct); 563 564 mtx_lock(&atrtc_time_lock); 565 mtx_lock_spin(&atrtc_lock); 566 567 /* Disable RTC updates and interrupts. */ 568 rtcout_locked(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR); 569 570 /* Write all the time registers. */ 571 rtcout_locked(RTC_SEC, bct.sec); 572 rtcout_locked(RTC_MIN, bct.min); 573 rtcout_locked(RTC_HRS, bct.hour); 574 rtcout_locked(RTC_WDAY, bct.dow + 1); 575 rtcout_locked(RTC_DAY, bct.day); 576 rtcout_locked(RTC_MONTH, bct.mon); 577 rtcout_locked(RTC_YEAR, bct.year & 0xff); 578 if (rtc_century) 579 rtcout_locked(rtc_century, bct.year >> 8); 580 581 /* 582 * Re-enable RTC updates and interrupts. 583 */ 584 rtcout_locked(RTC_STATUSB, rtc_statusb); 585 rtcin_locked(RTC_INTR); 586 587 mtx_unlock_spin(&atrtc_lock); 588 mtx_unlock(&atrtc_time_lock); 589 590 return (0); 591 } 592 593 static int 594 atrtc_gettime(device_t dev, struct timespec *ts) 595 { 596 struct bcd_clocktime bct; 597 598 /* Look if we have a RTC present and the time is valid */ 599 if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) { 600 device_printf(dev, "WARNING: Battery failure indication\n"); 601 return (EINVAL); 602 } 603 604 /* 605 * wait for time update to complete 606 * If RTCSA_TUP is zero, we have at least 244us before next update. 607 * This is fast enough on most hardware, but a refinement would be 608 * to make sure that no more than 240us pass after we start reading, 609 * and try again if so. 610 */ 611 mtx_lock(&atrtc_time_lock); 612 while (rtcin(RTC_STATUSA) & RTCSA_TUP) 613 continue; 614 mtx_lock_spin(&atrtc_lock); 615 bct.sec = rtcin_locked(RTC_SEC); 616 bct.min = rtcin_locked(RTC_MIN); 617 bct.hour = rtcin_locked(RTC_HRS); 618 bct.day = rtcin_locked(RTC_DAY); 619 bct.mon = rtcin_locked(RTC_MONTH); 620 bct.year = rtcin_locked(RTC_YEAR); 621 if (rtc_century) 622 bct.year |= rtcin_locked(rtc_century) << 8; 623 mtx_unlock_spin(&atrtc_lock); 624 mtx_unlock(&atrtc_time_lock); 625 /* dow is unused in timespec conversion and we have no nsec info. */ 626 bct.dow = 0; 627 bct.nsec = 0; 628 clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bct); 629 return (clock_bcd_to_ts(&bct, ts, false)); 630 } 631 632 static device_method_t atrtc_isa_methods[] = { 633 /* Device interface */ 634 DEVMETHOD(device_probe, atrtc_probe), 635 DEVMETHOD(device_attach, atrtc_isa_attach), 636 DEVMETHOD(device_detach, bus_generic_detach), 637 DEVMETHOD(device_shutdown, bus_generic_shutdown), 638 DEVMETHOD(device_suspend, bus_generic_suspend), 639 /* XXX stop statclock? */ 640 DEVMETHOD(device_resume, atrtc_resume), 641 642 /* clock interface */ 643 DEVMETHOD(clock_gettime, atrtc_gettime), 644 DEVMETHOD(clock_settime, atrtc_settime), 645 { 0, 0 } 646 }; 647 648 static driver_t atrtc_isa_driver = { 649 "atrtc", 650 atrtc_isa_methods, 651 sizeof(struct atrtc_softc), 652 }; 653 654 #ifdef DEV_ACPI 655 static device_method_t atrtc_acpi_methods[] = { 656 /* Device interface */ 657 DEVMETHOD(device_probe, atrtc_probe), 658 DEVMETHOD(device_attach, atrtc_acpi_attach), 659 DEVMETHOD(device_detach, atrtc_acpi_detach), 660 /* XXX stop statclock? */ 661 DEVMETHOD(device_resume, atrtc_resume), 662 663 /* clock interface */ 664 DEVMETHOD(clock_gettime, atrtc_gettime), 665 DEVMETHOD(clock_settime, atrtc_settime), 666 { 0, 0 } 667 }; 668 669 static driver_t atrtc_acpi_driver = { 670 "atrtc", 671 atrtc_acpi_methods, 672 sizeof(struct atrtc_softc), 673 }; 674 #endif /* DEV_ACPI */ 675 676 static devclass_t atrtc_devclass; 677 678 DRIVER_MODULE(atrtc, isa, atrtc_isa_driver, atrtc_devclass, 0, 0); 679 #ifdef DEV_ACPI 680 DRIVER_MODULE(atrtc, acpi, atrtc_acpi_driver, atrtc_devclass, 0, 0); 681 #endif 682 ISA_PNP_INFO(atrtc_ids); 683