clock.c revision 1.30.14.1
1 /* $NetBSD: clock.c,v 1.30.14.1 2010/04/21 00:33:46 matt Exp $ */ 2 3 /*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz and Don Ahn. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)clock.c 7.2 (Berkeley) 5/12/91 35 */ 36 /*- 37 * Copyright (c) 1993, 1994 Charles M. Hannum. 38 * 39 * This code is derived from software contributed to Berkeley by 40 * William Jolitz and Don Ahn. 41 * 42 * Redistribution and use in source and binary forms, with or without 43 * modification, are permitted provided that the following conditions 44 * are met: 45 * 1. Redistributions of source code must retain the above copyright 46 * notice, this list of conditions and the following disclaimer. 47 * 2. Redistributions in binary form must reproduce the above copyright 48 * notice, this list of conditions and the following disclaimer in the 49 * documentation and/or other materials provided with the distribution. 50 * 3. All advertising materials mentioning features or use of this software 51 * must display the following acknowledgement: 52 * This product includes software developed by the University of 53 * California, Berkeley and its contributors. 54 * 4. Neither the name of the University nor the names of its contributors 55 * may be used to endorse or promote products derived from this software 56 * without specific prior written permission. 57 * 58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 68 * SUCH DAMAGE. 69 * 70 * @(#)clock.c 7.2 (Berkeley) 5/12/91 71 */ 72 /* 73 * Mach Operating System 74 * Copyright (c) 1991,1990,1989 Carnegie Mellon University 75 * All Rights Reserved. 76 * 77 * Permission to use, copy, modify and distribute this software and its 78 * documentation is hereby granted, provided that both the copyright 79 * notice and this permission notice appear in all copies of the 80 * software, derivative works or modified versions, and any portions 81 * thereof, and that both notices appear in supporting documentation. 82 * 83 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 84 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 85 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 86 * 87 * Carnegie Mellon requests users of this software to return to 88 * 89 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 90 * School of Computer Science 91 * Carnegie Mellon University 92 * Pittsburgh PA 15213-3890 93 * 94 * any improvements or extensions that they make and grant Carnegie Mellon 95 * the rights to redistribute these changes. 96 */ 97 /* 98 Copyright 1988, 1989 by Intel Corporation, Santa Clara, California. 99 100 All Rights Reserved 101 102 Permission to use, copy, modify, and distribute this software and 103 its documentation for any purpose and without fee is hereby 104 granted, provided that the above copyright notice appears in all 105 copies and that both the copyright notice and this permission notice 106 appear in supporting documentation, and that the name of Intel 107 not be used in advertising or publicity pertaining to distribution 108 of the software without specific, written prior permission. 109 110 INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 111 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, 112 IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 113 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 114 LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 115 NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 116 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 117 */ 118 119 /* 120 * Primitive clock interrupt routines. 121 */ 122 123 #include <sys/cdefs.h> 124 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.30.14.1 2010/04/21 00:33:46 matt Exp $"); 125 126 /* #define CLOCKDEBUG */ 127 /* #define CLOCK_PARANOIA */ 128 129 #include "opt_multiprocessor.h" 130 #include "opt_ntp.h" 131 132 #include <sys/param.h> 133 #include <sys/systm.h> 134 #include <sys/time.h> 135 #include <sys/timetc.h> 136 #include <sys/kernel.h> 137 #include <sys/device.h> 138 #include <sys/mutex.h> 139 #include <sys/cpu.h> 140 #include <sys/intr.h> 141 142 #include <machine/pio.h> 143 #include <machine/cpufunc.h> 144 #include <machine/lock.h> 145 146 #include <dev/isa/isareg.h> 147 #include <dev/isa/isavar.h> 148 #include <dev/ic/mc146818reg.h> 149 #include <dev/ic/i8253reg.h> 150 #include <i386/isa/nvram.h> 151 #include <x86/x86/tsc.h> 152 #include <x86/lock.h> 153 #include <machine/specialreg.h> 154 #include <x86/rtc.h> 155 156 #ifndef __x86_64__ 157 #include "mca.h" 158 #endif 159 #if NMCA > 0 160 #include <machine/mca_machdep.h> /* for MCA_system */ 161 #endif 162 163 #include "pcppi.h" 164 #if (NPCPPI > 0) 165 #include <dev/isa/pcppivar.h> 166 167 int sysbeepmatch(device_t, cfdata_t, void *); 168 void sysbeepattach(device_t, device_t, void *); 169 int sysbeepdetach(device_t, int); 170 171 CFATTACH_DECL_NEW(sysbeep, 0, 172 sysbeepmatch, sysbeepattach, sysbeepdetach, NULL); 173 174 static int ppi_attached; 175 static pcppi_tag_t ppicookie; 176 #endif /* PCPPI */ 177 178 #ifdef CLOCKDEBUG 179 int clock_debug = 0; 180 #define DPRINTF(arg) if (clock_debug) printf arg 181 #else 182 #define DPRINTF(arg) 183 #endif 184 185 /* Used by lapic.c */ 186 unsigned int gettick(void); 187 void sysbeep(int, int); 188 static void tickle_tc(void); 189 190 static int clockintr(void *, struct intrframe *); 191 192 int sysbeepdetach(device_t, int); 193 194 static unsigned int gettick_broken_latch(void); 195 196 static volatile uint32_t i8254_lastcount; 197 static volatile uint32_t i8254_offset; 198 static volatile int i8254_ticked; 199 200 /* to protect TC timer variables */ 201 static __cpu_simple_lock_t tmr_lock = __SIMPLELOCK_UNLOCKED; 202 203 u_int i8254_get_timecount(struct timecounter *); 204 205 static struct timecounter i8254_timecounter = { 206 i8254_get_timecount, /* get_timecount */ 207 0, /* no poll_pps */ 208 ~0u, /* counter_mask */ 209 TIMER_FREQ, /* frequency */ 210 "i8254", /* name */ 211 100, /* quality */ 212 NULL, /* private data */ 213 NULL, /* next */ 214 }; 215 216 u_long rtclock_tval; /* i8254 reload value for countdown */ 217 int rtclock_init = 0; 218 219 int clock_broken_latch = 0; 220 221 #ifdef CLOCK_PARANOIA 222 static int ticks[6]; 223 #endif 224 /* 225 * i8254 latch check routine: 226 * National Geode (formerly Cyrix MediaGX) has a serious bug in 227 * its built-in i8254-compatible clock module. 228 * machdep sets the variable 'clock_broken_latch' to indicate it. 229 */ 230 231 static unsigned int 232 gettick_broken_latch(void) 233 { 234 int v1, v2, v3; 235 int w1, w2, w3; 236 int s; 237 238 /* Don't want someone screwing with the counter while we're here. */ 239 s = splhigh(); 240 __cpu_simple_lock(&tmr_lock); 241 v1 = inb(IO_TIMER1+TIMER_CNTR0); 242 v1 |= inb(IO_TIMER1+TIMER_CNTR0) << 8; 243 v2 = inb(IO_TIMER1+TIMER_CNTR0); 244 v2 |= inb(IO_TIMER1+TIMER_CNTR0) << 8; 245 v3 = inb(IO_TIMER1+TIMER_CNTR0); 246 v3 |= inb(IO_TIMER1+TIMER_CNTR0) << 8; 247 __cpu_simple_unlock(&tmr_lock); 248 splx(s); 249 250 #ifdef CLOCK_PARANOIA 251 if (clock_debug) { 252 ticks[0] = ticks[3]; 253 ticks[1] = ticks[4]; 254 ticks[2] = ticks[5]; 255 ticks[3] = v1; 256 ticks[4] = v2; 257 ticks[5] = v3; 258 } 259 #endif 260 261 if (v1 >= v2 && v2 >= v3 && v1 - v3 < 0x200) 262 return (v2); 263 264 #define _swap_val(a, b) do { \ 265 int c = a; \ 266 a = b; \ 267 b = c; \ 268 } while (0) 269 270 /* 271 * sort v1 v2 v3 272 */ 273 if (v1 < v2) 274 _swap_val(v1, v2); 275 if (v2 < v3) 276 _swap_val(v2, v3); 277 if (v1 < v2) 278 _swap_val(v1, v2); 279 280 /* 281 * compute the middle value 282 */ 283 284 if (v1 - v3 < 0x200) 285 return (v2); 286 287 w1 = v2 - v3; 288 w2 = v3 - v1 + rtclock_tval; 289 w3 = v1 - v2; 290 if (w1 >= w2) { 291 if (w1 >= w3) 292 return (v1); 293 } else { 294 if (w2 >= w3) 295 return (v2); 296 } 297 return (v3); 298 } 299 300 /* minimal initialization, enough for delay() */ 301 void 302 initrtclock(u_long freq) 303 { 304 u_long tval; 305 306 /* 307 * Compute timer_count, the count-down count the timer will be 308 * set to. Also, correctly round 309 * this by carrying an extra bit through the division. 310 */ 311 tval = (freq * 2) / (u_long) hz; 312 tval = (tval / 2) + (tval & 0x1); 313 314 /* initialize 8254 clock */ 315 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT); 316 317 /* Correct rounding will buy us a better precision in timekeeping */ 318 outb(IO_TIMER1+TIMER_CNTR0, tval % 256); 319 outb(IO_TIMER1+TIMER_CNTR0, tval / 256); 320 321 rtclock_tval = tval ? tval : 0xFFFF; 322 rtclock_init = 1; 323 } 324 325 void 326 startrtclock(void) 327 { 328 int s; 329 330 if (!rtclock_init) 331 initrtclock(TIMER_FREQ); 332 333 /* Check diagnostic status */ 334 if ((s = mc146818_read(NULL, NVRAM_DIAG)) != 0) { /* XXX softc */ 335 char bits[128]; 336 printf("RTC BIOS diagnostic error %s\n", 337 bitmask_snprintf(s, NVRAM_DIAG_BITS, bits, sizeof(bits))); 338 } 339 340 tc_init(&i8254_timecounter); 341 rtc_register(); 342 } 343 344 /* 345 * Must be called at splsched(). 346 */ 347 static void 348 tickle_tc(void) 349 { 350 #if defined(MULTIPROCESSOR) 351 struct cpu_info *ci = curcpu(); 352 /* 353 * If we are not the primary CPU, we're not allowed to do 354 * any more work. 355 */ 356 if (CPU_IS_PRIMARY(ci) == 0) 357 return; 358 #endif 359 if (rtclock_tval && timecounter->tc_get_timecount == i8254_get_timecount) { 360 __cpu_simple_lock(&tmr_lock); 361 if (i8254_ticked) 362 i8254_ticked = 0; 363 else { 364 i8254_offset += rtclock_tval; 365 i8254_lastcount = 0; 366 } 367 __cpu_simple_unlock(&tmr_lock); 368 } 369 370 } 371 372 static int 373 clockintr(void *arg, struct intrframe *frame) 374 { 375 tickle_tc(); 376 377 hardclock((struct clockframe *)frame); 378 379 #if NMCA > 0 380 if (MCA_system) { 381 /* Reset PS/2 clock interrupt by asserting bit 7 of port 0x61 */ 382 outb(0x61, inb(0x61) | 0x80); 383 } 384 #endif 385 return -1; 386 } 387 388 u_int 389 i8254_get_timecount(struct timecounter *tc) 390 { 391 u_int count; 392 uint16_t rdval; 393 u_long psl; 394 395 /* Don't want someone screwing with the counter while we're here. */ 396 psl = x86_read_psl(); 397 x86_disable_intr(); 398 __cpu_simple_lock(&tmr_lock); 399 /* Select timer0 and latch counter value. */ 400 outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0 | TIMER_LATCH); 401 /* insb to make the read atomic */ 402 rdval = inb(IO_TIMER1+TIMER_CNTR0); 403 rdval |= (inb(IO_TIMER1+TIMER_CNTR0) << 8); 404 count = rtclock_tval - rdval; 405 if (rtclock_tval && (count < i8254_lastcount && 406 (!i8254_ticked || rtclock_tval == 0xFFFF))) { 407 i8254_ticked = 1; 408 i8254_offset += rtclock_tval; 409 } 410 i8254_lastcount = count; 411 count += i8254_offset; 412 __cpu_simple_unlock(&tmr_lock); 413 x86_write_psl(psl); 414 415 return (count); 416 } 417 418 unsigned int 419 gettick(void) 420 { 421 uint16_t rdval; 422 u_long psl; 423 424 if (clock_broken_latch) 425 return (gettick_broken_latch()); 426 427 /* Don't want someone screwing with the counter while we're here. */ 428 psl = x86_read_psl(); 429 x86_disable_intr(); 430 __cpu_simple_lock(&tmr_lock); 431 /* Select counter 0 and latch it. */ 432 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0 | TIMER_LATCH); 433 rdval = inb(IO_TIMER1+TIMER_CNTR0); 434 rdval |= (inb(IO_TIMER1+TIMER_CNTR0) << 8); 435 __cpu_simple_unlock(&tmr_lock); 436 x86_write_psl(psl); 437 438 return rdval; 439 } 440 441 /* 442 * Wait approximately `n' microseconds. 443 * Relies on timer 1 counting down from (TIMER_FREQ / hz) at TIMER_FREQ Hz. 444 * Note: timer had better have been programmed before this is first used! 445 * (Note that we use `rate generator' mode, which counts at 1:1; `square 446 * wave' mode counts at 2:1). 447 * Don't rely on this being particularly accurate. 448 */ 449 void 450 i8254_delay(unsigned int n) 451 { 452 unsigned int cur_tick, initial_tick; 453 int remaining; 454 455 /* allow DELAY() to be used before startrtclock() */ 456 if (!rtclock_init) 457 initrtclock(TIMER_FREQ); 458 459 /* 460 * Read the counter first, so that the rest of the setup overhead is 461 * counted. 462 */ 463 initial_tick = gettick(); 464 465 if (n <= UINT_MAX / TIMER_FREQ) { 466 /* 467 * For unsigned arithmetic, division can be replaced with 468 * multiplication with the inverse and a shift. 469 */ 470 remaining = n * TIMER_FREQ / 1000000; 471 } else { 472 /* This is a very long delay. 473 * Being slow here doesn't matter. 474 */ 475 remaining = (unsigned long long) n * TIMER_FREQ / 1000000; 476 } 477 478 while (remaining > 1) { 479 #ifdef CLOCK_PARANOIA 480 int delta; 481 cur_tick = gettick(); 482 if (cur_tick > initial_tick) 483 delta = rtclock_tval - (cur_tick - initial_tick); 484 else 485 delta = initial_tick - cur_tick; 486 if (delta < 0 || delta >= rtclock_tval / 2) { 487 DPRINTF(("delay: ignore ticks %.4x-%.4x", 488 initial_tick, cur_tick)); 489 if (clock_broken_latch) { 490 DPRINTF((" (%.4x %.4x %.4x %.4x %.4x %.4x)\n", 491 ticks[0], ticks[1], ticks[2], 492 ticks[3], ticks[4], ticks[5])); 493 } else { 494 DPRINTF(("\n")); 495 } 496 } else 497 remaining -= delta; 498 #else 499 cur_tick = gettick(); 500 if (cur_tick > initial_tick) 501 remaining -= rtclock_tval - (cur_tick - initial_tick); 502 else 503 remaining -= initial_tick - cur_tick; 504 #endif 505 initial_tick = cur_tick; 506 } 507 } 508 509 #if (NPCPPI > 0) 510 int 511 sysbeepmatch(device_t parent, cfdata_t match, void *aux) 512 { 513 return (!ppi_attached); 514 } 515 516 void 517 sysbeepattach(device_t parent, device_t self, void *aux) 518 { 519 aprint_naive("\n"); 520 aprint_normal("\n"); 521 522 ppicookie = ((struct pcppi_attach_args *)aux)->pa_cookie; 523 ppi_attached = 1; 524 525 if (!pmf_device_register(self, NULL, NULL)) 526 aprint_error_dev(self, "couldn't establish power handler\n"); 527 } 528 529 int 530 sysbeepdetach(device_t self, int flags) 531 { 532 pmf_device_deregister(self); 533 ppi_attached = 0; 534 return 0; 535 } 536 #endif 537 538 void 539 sysbeep(int pitch, int period) 540 { 541 #if (NPCPPI > 0) 542 if (ppi_attached) 543 pcppi_bell(ppicookie, pitch, period, 0); 544 #endif 545 } 546 547 void 548 i8254_initclocks(void) 549 { 550 551 /* 552 * XXX If you're doing strange things with multiple clocks, you might 553 * want to keep track of clock handlers. 554 */ 555 (void)isa_intr_establish(NULL, 0, IST_PULSE, IPL_CLOCK, 556 (int (*)(void *))clockintr, 0); 557 } 558 559 void 560 setstatclockrate(int arg) 561 { 562 } 563
Indexes created Mon Oct 13 01:09:56 GMT 2025