time.c 32.5 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
/*
 *  linux/arch/x86-64/kernel/time.c
 *
 *  "High Precision Event Timer" based timekeeping.
 *
 *  Copyright (c) 1991,1992,1995  Linus Torvalds
 *  Copyright (c) 1994  Alan Modra
 *  Copyright (c) 1995  Markus Kuhn
 *  Copyright (c) 1996  Ingo Molnar
 *  Copyright (c) 1998  Andrea Arcangeli
 *  Copyright (c) 2002  Vojtech Pavlik
 *  Copyright (c) 2003  Andi Kleen
 *  RTC support code taken from arch/i386/kernel/timers/time_hpet.c
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/mc146818rtc.h>
#include <linux/time.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/sysdev.h>
#include <linux/bcd.h>
#include <linux/kallsyms.h>
A
Andi Kleen 已提交
28
#include <linux/acpi.h>
29
#ifdef CONFIG_ACPI
A
Andi Kleen 已提交
30
#include <acpi/achware.h>	/* for PM timer frequency */
31
#endif
L
Linus Torvalds 已提交
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
#include <asm/8253pit.h>
#include <asm/pgtable.h>
#include <asm/vsyscall.h>
#include <asm/timex.h>
#include <asm/proto.h>
#include <asm/hpet.h>
#include <asm/sections.h>
#include <linux/cpufreq.h>
#include <linux/hpet.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/apic.h>
#endif

#ifdef CONFIG_CPU_FREQ
static void cpufreq_delayed_get(void);
#endif
extern void i8254_timer_resume(void);
extern int using_apic_timer;

DEFINE_SPINLOCK(rtc_lock);
DEFINE_SPINLOCK(i8253_lock);

static int nohpet __initdata = 0;
static int notsc __initdata = 0;

#undef HPET_HACK_ENABLE_DANGEROUS

unsigned int cpu_khz;					/* TSC clocks / usec, not used here */
static unsigned long hpet_period;			/* fsecs / HPET clock */
unsigned long hpet_tick;				/* HPET clocks / interrupt */
62
static int hpet_use_timer;				/* Use counter of hpet for time keeping, otherwise PIT */
L
Linus Torvalds 已提交
63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103
unsigned long vxtime_hz = PIT_TICK_RATE;
int report_lost_ticks;				/* command line option */
unsigned long long monotonic_base;

struct vxtime_data __vxtime __section_vxtime;	/* for vsyscalls */

volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
unsigned long __wall_jiffies __section_wall_jiffies = INITIAL_JIFFIES;
struct timespec __xtime __section_xtime;
struct timezone __sys_tz __section_sys_tz;

static inline void rdtscll_sync(unsigned long *tsc)
{
#ifdef CONFIG_SMP
	sync_core();
#endif
	rdtscll(*tsc);
}

/*
 * do_gettimeoffset() returns microseconds since last timer interrupt was
 * triggered by hardware. A memory read of HPET is slower than a register read
 * of TSC, but much more reliable. It's also synchronized to the timer
 * interrupt. Note that do_gettimeoffset() may return more than hpet_tick, if a
 * timer interrupt has happened already, but vxtime.trigger wasn't updated yet.
 * This is not a problem, because jiffies hasn't updated either. They are bound
 * together by xtime_lock.
 */

static inline unsigned int do_gettimeoffset_tsc(void)
{
	unsigned long t;
	unsigned long x;
	rdtscll_sync(&t);
	if (t < vxtime.last_tsc) t = vxtime.last_tsc; /* hack */
	x = ((t - vxtime.last_tsc) * vxtime.tsc_quot) >> 32;
	return x;
}

static inline unsigned int do_gettimeoffset_hpet(void)
{
104 105 106
	/* cap counter read to one tick to avoid inconsistencies */
	unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last;
	return (min(counter,hpet_tick) * vxtime.quot) >> 32;
L
Linus Torvalds 已提交
107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173
}

unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;

/*
 * This version of gettimeofday() has microsecond resolution and better than
 * microsecond precision, as we're using at least a 10 MHz (usually 14.31818
 * MHz) HPET timer.
 */

void do_gettimeofday(struct timeval *tv)
{
	unsigned long seq, t;
 	unsigned int sec, usec;

	do {
		seq = read_seqbegin(&xtime_lock);

		sec = xtime.tv_sec;
		usec = xtime.tv_nsec / 1000;

		/* i386 does some correction here to keep the clock 
		   monotonous even when ntpd is fixing drift.
		   But they didn't work for me, there is a non monotonic
		   clock anyways with ntp.
		   I dropped all corrections now until a real solution can
		   be found. Note when you fix it here you need to do the same
		   in arch/x86_64/kernel/vsyscall.c and export all needed
		   variables in vmlinux.lds. -AK */ 

		t = (jiffies - wall_jiffies) * (1000000L / HZ) +
			do_gettimeoffset();
		usec += t;

	} while (read_seqretry(&xtime_lock, seq));

	tv->tv_sec = sec + usec / 1000000;
	tv->tv_usec = usec % 1000000;
}

EXPORT_SYMBOL(do_gettimeofday);

/*
 * settimeofday() first undoes the correction that gettimeofday would do
 * on the time, and then saves it. This is ugly, but has been like this for
 * ages already.
 */

int do_settimeofday(struct timespec *tv)
{
	time_t wtm_sec, sec = tv->tv_sec;
	long wtm_nsec, nsec = tv->tv_nsec;

	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
		return -EINVAL;

	write_seqlock_irq(&xtime_lock);

	nsec -= do_gettimeoffset() * 1000 +
		(jiffies - wall_jiffies) * (NSEC_PER_SEC/HZ);

	wtm_sec  = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
	wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);

	set_normalized_timespec(&xtime, sec, nsec);
	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);

J
john stultz 已提交
174
	ntp_clear();
L
Linus Torvalds 已提交
175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298

	write_sequnlock_irq(&xtime_lock);
	clock_was_set();
	return 0;
}

EXPORT_SYMBOL(do_settimeofday);

unsigned long profile_pc(struct pt_regs *regs)
{
	unsigned long pc = instruction_pointer(regs);

	/* Assume the lock function has either no stack frame or only a single word.
	   This checks if the address on the stack looks like a kernel text address.
	   There is a small window for false hits, but in that case the tick
	   is just accounted to the spinlock function.
	   Better would be to write these functions in assembler again
	   and check exactly. */
	if (in_lock_functions(pc)) {
		char *v = *(char **)regs->rsp;
		if ((v >= _stext && v <= _etext) ||
			(v >= _sinittext && v <= _einittext) ||
			(v >= (char *)MODULES_VADDR  && v <= (char *)MODULES_END))
			return (unsigned long)v;
		return ((unsigned long *)regs->rsp)[1];
	}
	return pc;
}
EXPORT_SYMBOL(profile_pc);

/*
 * In order to set the CMOS clock precisely, set_rtc_mmss has to be called 500
 * ms after the second nowtime has started, because when nowtime is written
 * into the registers of the CMOS clock, it will jump to the next second
 * precisely 500 ms later. Check the Motorola MC146818A or Dallas DS12887 data
 * sheet for details.
 */

static void set_rtc_mmss(unsigned long nowtime)
{
	int real_seconds, real_minutes, cmos_minutes;
	unsigned char control, freq_select;

/*
 * IRQs are disabled when we're called from the timer interrupt,
 * no need for spin_lock_irqsave()
 */

	spin_lock(&rtc_lock);

/*
 * Tell the clock it's being set and stop it.
 */

	control = CMOS_READ(RTC_CONTROL);
	CMOS_WRITE(control | RTC_SET, RTC_CONTROL);

	freq_select = CMOS_READ(RTC_FREQ_SELECT);
	CMOS_WRITE(freq_select | RTC_DIV_RESET2, RTC_FREQ_SELECT);

	cmos_minutes = CMOS_READ(RTC_MINUTES);
		BCD_TO_BIN(cmos_minutes);

/*
 * since we're only adjusting minutes and seconds, don't interfere with hour
 * overflow. This avoids messing with unknown time zones but requires your RTC
 * not to be off by more than 15 minutes. Since we're calling it only when
 * our clock is externally synchronized using NTP, this shouldn't be a problem.
 */

	real_seconds = nowtime % 60;
	real_minutes = nowtime / 60;
	if (((abs(real_minutes - cmos_minutes) + 15) / 30) & 1)
		real_minutes += 30;		/* correct for half hour time zone */
	real_minutes %= 60;

#if 0
	/* AMD 8111 is a really bad time keeper and hits this regularly. 
	   It probably was an attempt to avoid screwing up DST, but ignore
	   that for now. */	   
	if (abs(real_minutes - cmos_minutes) >= 30) {
		printk(KERN_WARNING "time.c: can't update CMOS clock "
		       "from %d to %d\n", cmos_minutes, real_minutes);
	} else
#endif

	{
			BIN_TO_BCD(real_seconds);
			BIN_TO_BCD(real_minutes);
		CMOS_WRITE(real_seconds, RTC_SECONDS);
		CMOS_WRITE(real_minutes, RTC_MINUTES);
	}

/*
 * The following flags have to be released exactly in this order, otherwise the
 * DS12887 (popular MC146818A clone with integrated battery and quartz) will
 * not reset the oscillator and will not update precisely 500 ms later. You
 * won't find this mentioned in the Dallas Semiconductor data sheets, but who
 * believes data sheets anyway ... -- Markus Kuhn
 */

	CMOS_WRITE(control, RTC_CONTROL);
	CMOS_WRITE(freq_select, RTC_FREQ_SELECT);

	spin_unlock(&rtc_lock);
}


/* monotonic_clock(): returns # of nanoseconds passed since time_init()
 *		Note: This function is required to return accurate
 *		time even in the absence of multiple timer ticks.
 */
unsigned long long monotonic_clock(void)
{
	unsigned long seq;
 	u32 last_offset, this_offset, offset;
	unsigned long long base;

	if (vxtime.mode == VXTIME_HPET) {
		do {
			seq = read_seqbegin(&xtime_lock);

			last_offset = vxtime.last;
			base = monotonic_base;
299
			this_offset = hpet_readl(HPET_COUNTER);
L
Linus Torvalds 已提交
300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374

		} while (read_seqretry(&xtime_lock, seq));
		offset = (this_offset - last_offset);
		offset *=(NSEC_PER_SEC/HZ)/hpet_tick;
		return base + offset;
	}else{
		do {
			seq = read_seqbegin(&xtime_lock);

			last_offset = vxtime.last_tsc;
			base = monotonic_base;
		} while (read_seqretry(&xtime_lock, seq));
		sync_core();
		rdtscll(this_offset);
		offset = (this_offset - last_offset)*1000/cpu_khz; 
		return base + offset;
	}


}
EXPORT_SYMBOL(monotonic_clock);

static noinline void handle_lost_ticks(int lost, struct pt_regs *regs)
{
    static long lost_count;
    static int warned;

    if (report_lost_ticks) {
	    printk(KERN_WARNING "time.c: Lost %d timer "
		   "tick(s)! ", lost);
	    print_symbol("rip %s)\n", regs->rip);
    }

    if (lost_count == 1000 && !warned) {
	    printk(KERN_WARNING
		   "warning: many lost ticks.\n"
		   KERN_WARNING "Your time source seems to be instable or "
		   		"some driver is hogging interupts\n");
	    print_symbol("rip %s\n", regs->rip);
	    if (vxtime.mode == VXTIME_TSC && vxtime.hpet_address) {
		    printk(KERN_WARNING "Falling back to HPET\n");
		    vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
		    vxtime.mode = VXTIME_HPET;
		    do_gettimeoffset = do_gettimeoffset_hpet;
	    }
	    /* else should fall back to PIT, but code missing. */
	    warned = 1;
    } else
	    lost_count++;

#ifdef CONFIG_CPU_FREQ
    /* In some cases the CPU can change frequency without us noticing
       (like going into thermal throttle)
       Give cpufreq a change to catch up. */
    if ((lost_count+1) % 25 == 0) {
	    cpufreq_delayed_get();
    }
#endif
}

static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	static unsigned long rtc_update = 0;
	unsigned long tsc;
	int delay, offset = 0, lost = 0;

/*
 * Here we are in the timer irq handler. We have irqs locally disabled (so we
 * don't need spin_lock_irqsave()) but we don't know if the timer_bh is running
 * on the other CPU, so we need a lock. We also need to lock the vsyscall
 * variables, because both do_timer() and us change them -arca+vojtech
 */

	write_seqlock(&xtime_lock);

375 376 377 378 379 380 381 382
	if (vxtime.hpet_address)
		offset = hpet_readl(HPET_COUNTER);

	if (hpet_use_timer) {
		/* if we're using the hpet timer functionality,
		 * we can more accurately know the counter value
		 * when the timer interrupt occured.
		 */
L
Linus Torvalds 已提交
383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404
		offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
		delay = hpet_readl(HPET_COUNTER) - offset;
	} else {
		spin_lock(&i8253_lock);
		outb_p(0x00, 0x43);
		delay = inb_p(0x40);
		delay |= inb(0x40) << 8;
		spin_unlock(&i8253_lock);
		delay = LATCH - 1 - delay;
	}

	rdtscll_sync(&tsc);

	if (vxtime.mode == VXTIME_HPET) {
		if (offset - vxtime.last > hpet_tick) {
			lost = (offset - vxtime.last) / hpet_tick - 1;
		}

		monotonic_base += 
			(offset - vxtime.last)*(NSEC_PER_SEC/HZ) / hpet_tick;

		vxtime.last = offset;
A
Andi Kleen 已提交
405 406 407 408
#ifdef CONFIG_X86_PM_TIMER
	} else if (vxtime.mode == VXTIME_PMTMR) {
		lost = pmtimer_mark_offset();
#endif
L
Linus Torvalds 已提交
409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465
	} else {
		offset = (((tsc - vxtime.last_tsc) *
			   vxtime.tsc_quot) >> 32) - (USEC_PER_SEC / HZ);

		if (offset < 0)
			offset = 0;

		if (offset > (USEC_PER_SEC / HZ)) {
			lost = offset / (USEC_PER_SEC / HZ);
			offset %= (USEC_PER_SEC / HZ);
		}

		monotonic_base += (tsc - vxtime.last_tsc)*1000000/cpu_khz ;

		vxtime.last_tsc = tsc - vxtime.quot * delay / vxtime.tsc_quot;

		if ((((tsc - vxtime.last_tsc) *
		      vxtime.tsc_quot) >> 32) < offset)
			vxtime.last_tsc = tsc -
				(((long) offset << 32) / vxtime.tsc_quot) - 1;
	}

	if (lost > 0) {
		handle_lost_ticks(lost, regs);
		jiffies += lost;
	}

/*
 * Do the timer stuff.
 */

	do_timer(regs);
#ifndef CONFIG_SMP
	update_process_times(user_mode(regs));
#endif

/*
 * In the SMP case we use the local APIC timer interrupt to do the profiling,
 * except when we simulate SMP mode on a uniprocessor system, in that case we
 * have to call the local interrupt handler.
 */

#ifndef CONFIG_X86_LOCAL_APIC
	profile_tick(CPU_PROFILING, regs);
#else
	if (!using_apic_timer)
		smp_local_timer_interrupt(regs);
#endif

/*
 * If we have an externally synchronized Linux clock, then update CMOS clock
 * accordingly every ~11 minutes. set_rtc_mmss() will be called in the jiffy
 * closest to exactly 500 ms before the next second. If the update fails, we
 * don't care, as it'll be updated on the next turn, and the problem (time way
 * off) isn't likely to go away much sooner anyway.
 */

J
john stultz 已提交
466
	if (ntp_synced() && xtime.tv_sec > rtc_update &&
L
Linus Torvalds 已提交
467 468 469 470 471 472 473 474 475 476 477 478 479
		abs(xtime.tv_nsec - 500000000) <= tick_nsec / 2) {
		set_rtc_mmss(xtime.tv_sec);
		rtc_update = xtime.tv_sec + 660;
	}
 
	write_sequnlock(&xtime_lock);

	return IRQ_HANDLED;
}

static unsigned int cyc2ns_scale;
#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */

480
static inline void set_cyc2ns_scale(unsigned long cpu_khz)
L
Linus Torvalds 已提交
481
{
482
	cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz;
L
Linus Torvalds 已提交
483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626
}

static inline unsigned long long cycles_2_ns(unsigned long long cyc)
{
	return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
}

unsigned long long sched_clock(void)
{
	unsigned long a = 0;

#if 0
	/* Don't do a HPET read here. Using TSC always is much faster
	   and HPET may not be mapped yet when the scheduler first runs.
           Disadvantage is a small drift between CPUs in some configurations,
	   but that should be tolerable. */
	if (__vxtime.mode == VXTIME_HPET)
		return (hpet_readl(HPET_COUNTER) * vxtime.quot) >> 32;
#endif

	/* Could do CPU core sync here. Opteron can execute rdtsc speculatively,
	   which means it is not completely exact and may not be monotonous between
	   CPUs. But the errors should be too small to matter for scheduling
	   purposes. */

	rdtscll(a);
	return cycles_2_ns(a);
}

unsigned long get_cmos_time(void)
{
	unsigned int timeout, year, mon, day, hour, min, sec;
	unsigned char last, this;
	unsigned long flags;

/*
 * The Linux interpretation of the CMOS clock register contents: When the
 * Update-In-Progress (UIP) flag goes from 1 to 0, the RTC registers show the
 * second which has precisely just started. Waiting for this can take up to 1
 * second, we timeout approximately after 2.4 seconds on a machine with
 * standard 8.3 MHz ISA bus.
 */

	spin_lock_irqsave(&rtc_lock, flags);

	timeout = 1000000;
	last = this = 0;

	while (timeout && last && !this) {
		last = this;
		this = CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP;
		timeout--;
	}

/*
 * Here we are safe to assume the registers won't change for a whole second, so
 * we just go ahead and read them.
	 */

		sec = CMOS_READ(RTC_SECONDS);
		min = CMOS_READ(RTC_MINUTES);
		hour = CMOS_READ(RTC_HOURS);
		day = CMOS_READ(RTC_DAY_OF_MONTH);
		mon = CMOS_READ(RTC_MONTH);
		year = CMOS_READ(RTC_YEAR);

	spin_unlock_irqrestore(&rtc_lock, flags);

/*
 * We know that x86-64 always uses BCD format, no need to check the config
 * register.
 */

	    BCD_TO_BIN(sec);
	    BCD_TO_BIN(min);
	    BCD_TO_BIN(hour);
	    BCD_TO_BIN(day);
	    BCD_TO_BIN(mon);
	    BCD_TO_BIN(year);

/*
 * x86-64 systems only exists since 2002.
 * This will work up to Dec 31, 2100
 */
	year += 2000;

	return mktime(year, mon, day, hour, min, sec);
}

#ifdef CONFIG_CPU_FREQ

/* Frequency scaling support. Adjust the TSC based timer when the cpu frequency
   changes.
   
   RED-PEN: On SMP we assume all CPUs run with the same frequency.  It's
   not that important because current Opteron setups do not support
   scaling on SMP anyroads.

   Should fix up last_tsc too. Currently gettimeofday in the
   first tick after the change will be slightly wrong. */

#include <linux/workqueue.h>

static unsigned int cpufreq_delayed_issched = 0;
static unsigned int cpufreq_init = 0;
static struct work_struct cpufreq_delayed_get_work;

static void handle_cpufreq_delayed_get(void *v)
{
	unsigned int cpu;
	for_each_online_cpu(cpu) {
		cpufreq_get(cpu);
	}
	cpufreq_delayed_issched = 0;
}

/* if we notice lost ticks, schedule a call to cpufreq_get() as it tries
 * to verify the CPU frequency the timing core thinks the CPU is running
 * at is still correct.
 */
static void cpufreq_delayed_get(void)
{
	static int warned;
	if (cpufreq_init && !cpufreq_delayed_issched) {
		cpufreq_delayed_issched = 1;
		if (!warned) {
			warned = 1;
			printk(KERN_DEBUG "Losing some ticks... checking if CPU frequency changed.\n");
		}
		schedule_work(&cpufreq_delayed_get_work);
	}
}

static unsigned int  ref_freq = 0;
static unsigned long loops_per_jiffy_ref = 0;

static unsigned long cpu_khz_ref = 0;

static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
				 void *data)
{
        struct cpufreq_freqs *freq = data;
	unsigned long *lpj, dummy;

627 628 629
	if (cpu_has(&cpu_data[freq->cpu], X86_FEATURE_CONSTANT_TSC))
		return 0;

L
Linus Torvalds 已提交
630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653
	lpj = &dummy;
	if (!(freq->flags & CPUFREQ_CONST_LOOPS))
#ifdef CONFIG_SMP
	lpj = &cpu_data[freq->cpu].loops_per_jiffy;
#else
	lpj = &boot_cpu_data.loops_per_jiffy;
#endif

	if (!ref_freq) {
		ref_freq = freq->old;
		loops_per_jiffy_ref = *lpj;
		cpu_khz_ref = cpu_khz;
	}
        if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
            (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
	    (val == CPUFREQ_RESUMECHANGE)) {
                *lpj =
		cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new);

		cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new);
		if (!(freq->flags & CPUFREQ_CONST_LOOPS))
			vxtime.tsc_quot = (1000L << 32) / cpu_khz;
	}
	
654
	set_cyc2ns_scale(cpu_khz_ref);
L
Linus Torvalds 已提交
655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807

	return 0;
}
 
static struct notifier_block time_cpufreq_notifier_block = {
         .notifier_call  = time_cpufreq_notifier
};

static int __init cpufreq_tsc(void)
{
	INIT_WORK(&cpufreq_delayed_get_work, handle_cpufreq_delayed_get, NULL);
	if (!cpufreq_register_notifier(&time_cpufreq_notifier_block,
				       CPUFREQ_TRANSITION_NOTIFIER))
		cpufreq_init = 1;
	return 0;
}

core_initcall(cpufreq_tsc);

#endif

/*
 * calibrate_tsc() calibrates the processor TSC in a very simple way, comparing
 * it to the HPET timer of known frequency.
 */

#define TICK_COUNT 100000000

static unsigned int __init hpet_calibrate_tsc(void)
{
	int tsc_start, hpet_start;
	int tsc_now, hpet_now;
	unsigned long flags;

	local_irq_save(flags);
	local_irq_disable();

	hpet_start = hpet_readl(HPET_COUNTER);
	rdtscl(tsc_start);

	do {
		local_irq_disable();
		hpet_now = hpet_readl(HPET_COUNTER);
		sync_core();
		rdtscl(tsc_now);
		local_irq_restore(flags);
	} while ((tsc_now - tsc_start) < TICK_COUNT &&
		 (hpet_now - hpet_start) < TICK_COUNT);

	return (tsc_now - tsc_start) * 1000000000L
		/ ((hpet_now - hpet_start) * hpet_period / 1000);
}


/*
 * pit_calibrate_tsc() uses the speaker output (channel 2) of
 * the PIT. This is better than using the timer interrupt output,
 * because we can read the value of the speaker with just one inb(),
 * where we need three i/o operations for the interrupt channel.
 * We count how many ticks the TSC does in 50 ms.
 */

static unsigned int __init pit_calibrate_tsc(void)
{
	unsigned long start, end;
	unsigned long flags;

	spin_lock_irqsave(&i8253_lock, flags);

	outb((inb(0x61) & ~0x02) | 0x01, 0x61);

	outb(0xb0, 0x43);
	outb((PIT_TICK_RATE / (1000 / 50)) & 0xff, 0x42);
	outb((PIT_TICK_RATE / (1000 / 50)) >> 8, 0x42);
	rdtscll(start);
	sync_core();
	while ((inb(0x61) & 0x20) == 0);
	sync_core();
	rdtscll(end);

	spin_unlock_irqrestore(&i8253_lock, flags);
	
	return (end - start) / 50;
}

#ifdef	CONFIG_HPET
static __init int late_hpet_init(void)
{
	struct hpet_data	hd;
	unsigned int 		ntimer;

	if (!vxtime.hpet_address)
          return -1;

	memset(&hd, 0, sizeof (hd));

	ntimer = hpet_readl(HPET_ID);
	ntimer = (ntimer & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT;
	ntimer++;

	/*
	 * Register with driver.
	 * Timer0 and Timer1 is used by platform.
	 */
	hd.hd_phys_address = vxtime.hpet_address;
	hd.hd_address = (void *)fix_to_virt(FIX_HPET_BASE);
	hd.hd_nirqs = ntimer;
	hd.hd_flags = HPET_DATA_PLATFORM;
	hpet_reserve_timer(&hd, 0);
#ifdef	CONFIG_HPET_EMULATE_RTC
	hpet_reserve_timer(&hd, 1);
#endif
	hd.hd_irq[0] = HPET_LEGACY_8254;
	hd.hd_irq[1] = HPET_LEGACY_RTC;
	if (ntimer > 2) {
		struct hpet		*hpet;
		struct hpet_timer	*timer;
		int			i;

		hpet = (struct hpet *) fix_to_virt(FIX_HPET_BASE);

		for (i = 2, timer = &hpet->hpet_timers[2]; i < ntimer;
		     timer++, i++)
			hd.hd_irq[i] = (timer->hpet_config &
					Tn_INT_ROUTE_CNF_MASK) >>
				Tn_INT_ROUTE_CNF_SHIFT;

	}

	hpet_alloc(&hd);
	return 0;
}
fs_initcall(late_hpet_init);
#endif

static int hpet_timer_stop_set_go(unsigned long tick)
{
	unsigned int cfg;

/*
 * Stop the timers and reset the main counter.
 */

	cfg = hpet_readl(HPET_CFG);
	cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY);
	hpet_writel(cfg, HPET_CFG);
	hpet_writel(0, HPET_COUNTER);
	hpet_writel(0, HPET_COUNTER + 4);

/*
 * Set up timer 0, as periodic with first interrupt to happen at hpet_tick,
 * and period also hpet_tick.
 */
808 809
	if (hpet_use_timer) {
		hpet_writel(HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL |
L
Linus Torvalds 已提交
810
		    HPET_TN_32BIT, HPET_T0_CFG);
811 812 813 814
		hpet_writel(hpet_tick, HPET_T0_CMP);
		hpet_writel(hpet_tick, HPET_T0_CMP); /* AK: why twice? */
		cfg |= HPET_CFG_LEGACY;
	}
L
Linus Torvalds 已提交
815 816 817 818
/*
 * Go!
 */

819
	cfg |= HPET_CFG_ENABLE;
L
Linus Torvalds 已提交
820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839
	hpet_writel(cfg, HPET_CFG);

	return 0;
}

static int hpet_init(void)
{
	unsigned int id;

	if (!vxtime.hpet_address)
		return -1;
	set_fixmap_nocache(FIX_HPET_BASE, vxtime.hpet_address);
	__set_fixmap(VSYSCALL_HPET, vxtime.hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);

/*
 * Read the period, compute tick and quotient.
 */

	id = hpet_readl(HPET_ID);

840
	if (!(id & HPET_ID_VENDOR) || !(id & HPET_ID_NUMBER))
L
Linus Torvalds 已提交
841 842 843 844 845 846 847 848 849
		return -1;

	hpet_period = hpet_readl(HPET_PERIOD);
	if (hpet_period < 100000 || hpet_period > 100000000)
		return -1;

	hpet_tick = (1000000000L * (USEC_PER_SEC / HZ) + hpet_period / 2) /
		hpet_period;

850 851
	hpet_use_timer = (id & HPET_ID_LEGSUP);

L
Linus Torvalds 已提交
852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907
	return hpet_timer_stop_set_go(hpet_tick);
}

static int hpet_reenable(void)
{
	return hpet_timer_stop_set_go(hpet_tick);
}

void __init pit_init(void)
{
	unsigned long flags;

	spin_lock_irqsave(&i8253_lock, flags);
	outb_p(0x34, 0x43);		/* binary, mode 2, LSB/MSB, ch 0 */
	outb_p(LATCH & 0xff, 0x40);	/* LSB */
	outb_p(LATCH >> 8, 0x40);	/* MSB */
	spin_unlock_irqrestore(&i8253_lock, flags);
}

int __init time_setup(char *str)
{
	report_lost_ticks = 1;
	return 1;
}

static struct irqaction irq0 = {
	timer_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "timer", NULL, NULL
};

extern void __init config_acpi_tables(void);

void __init time_init(void)
{
	char *timename;

#ifdef HPET_HACK_ENABLE_DANGEROUS
        if (!vxtime.hpet_address) {
		printk(KERN_WARNING "time.c: WARNING: Enabling HPET base "
		       "manually!\n");
                outl(0x800038a0, 0xcf8);
                outl(0xff000001, 0xcfc);
                outl(0x800038a0, 0xcf8);
                vxtime.hpet_address = inl(0xcfc) & 0xfffffffe;
		printk(KERN_WARNING "time.c: WARNING: Enabled HPET "
		       "at %#lx.\n", vxtime.hpet_address);
        }
#endif
	if (nohpet)
		vxtime.hpet_address = 0;

	xtime.tv_sec = get_cmos_time();
	xtime.tv_nsec = 0;

	set_normalized_timespec(&wall_to_monotonic,
	                        -xtime.tv_sec, -xtime.tv_nsec);

908
	if (!hpet_init())
L
Linus Torvalds 已提交
909 910
                vxtime_hz = (1000000000000000L + hpet_period / 2) /
			hpet_period;
911 912
	else
		vxtime.hpet_address = 0;
913 914

	if (hpet_use_timer) {
L
Linus Torvalds 已提交
915 916
		cpu_khz = hpet_calibrate_tsc();
		timename = "HPET";
A
Andi Kleen 已提交
917
#ifdef CONFIG_X86_PM_TIMER
918
	} else if (pmtmr_ioport && !vxtime.hpet_address) {
A
Andi Kleen 已提交
919 920 921 922 923
		vxtime_hz = PM_TIMER_FREQUENCY;
		timename = "PM";
		pit_init();
		cpu_khz = pit_calibrate_tsc();
#endif
L
Linus Torvalds 已提交
924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939
	} else {
		pit_init();
		cpu_khz = pit_calibrate_tsc();
		timename = "PIT";
	}

	printk(KERN_INFO "time.c: Using %ld.%06ld MHz %s timer.\n",
	       vxtime_hz / 1000000, vxtime_hz % 1000000, timename);
	printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
		cpu_khz / 1000, cpu_khz % 1000);
	vxtime.mode = VXTIME_TSC;
	vxtime.quot = (1000000L << 32) / vxtime_hz;
	vxtime.tsc_quot = (1000L << 32) / cpu_khz;
	rdtscll_sync(&vxtime.last_tsc);
	setup_irq(0, &irq0);

940
	set_cyc2ns_scale(cpu_khz);
941 942 943 944

#ifndef CONFIG_SMP
	time_init_gtod();
#endif
L
Linus Torvalds 已提交
945 946
}

A
Andi Kleen 已提交
947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964
/*
 * Make an educated guess if the TSC is trustworthy and synchronized
 * over all CPUs.
 */
static __init int unsynchronized_tsc(void)
{
#ifdef CONFIG_SMP
	if (oem_force_hpet_timer())
		return 1;
 	/* Intel systems are normally all synchronized. Exceptions
 	   are handled in the OEM check above. */
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		return 0;
#endif
 	/* Assume multi socket systems are not synchronized */
 	return num_online_cpus() > 1;
}

965 966 967 968
/*
 * Decide after all CPUs are booted what mode gettimeofday should use.
 */
void __init time_init_gtod(void)
L
Linus Torvalds 已提交
969 970 971
{
	char *timetype;

A
Andi Kleen 已提交
972
	if (unsynchronized_tsc())
L
Linus Torvalds 已提交
973 974
		notsc = 1;
	if (vxtime.hpet_address && notsc) {
975
		timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
L
Linus Torvalds 已提交
976 977 978
		vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
		vxtime.mode = VXTIME_HPET;
		do_gettimeoffset = do_gettimeoffset_hpet;
A
Andi Kleen 已提交
979 980 981 982 983 984 985 986 987 988
#ifdef CONFIG_X86_PM_TIMER
	/* Using PM for gettimeofday is quite slow, but we have no other
	   choice because the TSC is too unreliable on some systems. */
	} else if (pmtmr_ioport && !vxtime.hpet_address && notsc) {
		timetype = "PM";
		do_gettimeoffset = do_gettimeoffset_pm;
		vxtime.mode = VXTIME_PMTMR;
		sysctl_vsyscall = 0;
		printk(KERN_INFO "Disabling vsyscall due to use of PM timer\n");
#endif
L
Linus Torvalds 已提交
989
	} else {
990
		timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
L
Linus Torvalds 已提交
991 992 993 994 995 996 997 998 999 1000 1001
		vxtime.mode = VXTIME_TSC;
	}

	printk(KERN_INFO "time.c: Using %s based timekeeping.\n", timetype);
}

__setup("report_lost_ticks", time_setup);

static long clock_cmos_diff;
static unsigned long sleep_start;

1002
static int timer_suspend(struct sys_device *dev, pm_message_t state)
L
Linus Torvalds 已提交
1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033
{
	/*
	 * Estimate time zone so that set_time can update the clock
	 */
	long cmos_time =  get_cmos_time();

	clock_cmos_diff = -cmos_time;
	clock_cmos_diff += get_seconds();
	sleep_start = cmos_time;
	return 0;
}

static int timer_resume(struct sys_device *dev)
{
	unsigned long flags;
	unsigned long sec;
	unsigned long ctime = get_cmos_time();
	unsigned long sleep_length = (ctime - sleep_start) * HZ;

	if (vxtime.hpet_address)
		hpet_reenable();
	else
		i8254_timer_resume();

	sec = ctime + clock_cmos_diff;
	write_seqlock_irqsave(&xtime_lock,flags);
	xtime.tv_sec = sec;
	xtime.tv_nsec = 0;
	write_sequnlock_irqrestore(&xtime_lock,flags);
	jiffies += sleep_length;
	wall_jiffies += sleep_length;
I
Ingo Molnar 已提交
1034
	touch_softlockup_watchdog();
L
Linus Torvalds 已提交
1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091
	return 0;
}

static struct sysdev_class timer_sysclass = {
	.resume = timer_resume,
	.suspend = timer_suspend,
	set_kset_name("timer"),
};


/* XXX this driverfs stuff should probably go elsewhere later -john */
static struct sys_device device_timer = {
	.id	= 0,
	.cls	= &timer_sysclass,
};

static int time_init_device(void)
{
	int error = sysdev_class_register(&timer_sysclass);
	if (!error)
		error = sysdev_register(&device_timer);
	return error;
}

device_initcall(time_init_device);

#ifdef CONFIG_HPET_EMULATE_RTC
/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET
 * is enabled, we support RTC interrupt functionality in software.
 * RTC has 3 kinds of interrupts:
 * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock
 *    is updated
 * 2) Alarm Interrupt - generate an interrupt at a specific time of day
 * 3) Periodic Interrupt - generate periodic interrupt, with frequencies
 *    2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2)
 * (1) and (2) above are implemented using polling at a frequency of
 * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt
 * overhead. (DEFAULT_RTC_INT_FREQ)
 * For (3), we use interrupts at 64Hz or user specified periodic
 * frequency, whichever is higher.
 */
#include <linux/rtc.h>

#define DEFAULT_RTC_INT_FREQ 	64
#define RTC_NUM_INTS 		1

static unsigned long UIE_on;
static unsigned long prev_update_sec;

static unsigned long AIE_on;
static struct rtc_time alarm_time;

static unsigned long PIE_on;
static unsigned long PIE_freq = DEFAULT_RTC_INT_FREQ;
static unsigned long PIE_count;

static unsigned long hpet_rtc_int_freq; /* RTC interrupt frequency */
1092
static unsigned int hpet_t1_cmp; /* cached comparator register */
L
Linus Torvalds 已提交
1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128

int is_hpet_enabled(void)
{
	return vxtime.hpet_address != 0;
}

/*
 * Timer 1 for RTC, we do not use periodic interrupt feature,
 * even if HPET supports periodic interrupts on Timer 1.
 * The reason being, to set up a periodic interrupt in HPET, we need to
 * stop the main counter. And if we do that everytime someone diables/enables
 * RTC, we will have adverse effect on main kernel timer running on Timer 0.
 * So, for the time being, simulate the periodic interrupt in software.
 *
 * hpet_rtc_timer_init() is called for the first time and during subsequent
 * interuppts reinit happens through hpet_rtc_timer_reinit().
 */
int hpet_rtc_timer_init(void)
{
	unsigned int cfg, cnt;
	unsigned long flags;

	if (!is_hpet_enabled())
		return 0;
	/*
	 * Set the counter 1 and enable the interrupts.
	 */
	if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
		hpet_rtc_int_freq = PIE_freq;
	else
		hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;

	local_irq_save(flags);
	cnt = hpet_readl(HPET_COUNTER);
	cnt += ((hpet_tick*HZ)/hpet_rtc_int_freq);
	hpet_writel(cnt, HPET_T1_CMP);
1129
	hpet_t1_cmp = cnt;
L
Linus Torvalds 已提交
1130 1131 1132
	local_irq_restore(flags);

	cfg = hpet_readl(HPET_T1_CFG);
1133 1134
	cfg &= ~HPET_TN_PERIODIC;
	cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
L
Linus Torvalds 已提交
1135 1136 1137 1138 1139 1140 1141 1142 1143
	hpet_writel(cfg, HPET_T1_CFG);

	return 1;
}

static void hpet_rtc_timer_reinit(void)
{
	unsigned int cfg, cnt;

1144 1145 1146 1147
	if (unlikely(!(PIE_on | AIE_on | UIE_on))) {
		cfg = hpet_readl(HPET_T1_CFG);
		cfg &= ~HPET_TN_ENABLE;
		hpet_writel(cfg, HPET_T1_CFG);
L
Linus Torvalds 已提交
1148
		return;
1149
	}
L
Linus Torvalds 已提交
1150 1151 1152 1153 1154 1155 1156

	if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
		hpet_rtc_int_freq = PIE_freq;
	else
		hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;

	/* It is more accurate to use the comparator value than current count.*/
1157
	cnt = hpet_t1_cmp;
L
Linus Torvalds 已提交
1158 1159
	cnt += hpet_tick*HZ/hpet_rtc_int_freq;
	hpet_writel(cnt, HPET_T1_CMP);
1160
	hpet_t1_cmp = cnt;
L
Linus Torvalds 已提交
1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305
}

/*
 * The functions below are called from rtc driver.
 * Return 0 if HPET is not being used.
 * Otherwise do the necessary changes and return 1.
 */
int hpet_mask_rtc_irq_bit(unsigned long bit_mask)
{
	if (!is_hpet_enabled())
		return 0;

	if (bit_mask & RTC_UIE)
		UIE_on = 0;
	if (bit_mask & RTC_PIE)
		PIE_on = 0;
	if (bit_mask & RTC_AIE)
		AIE_on = 0;

	return 1;
}

int hpet_set_rtc_irq_bit(unsigned long bit_mask)
{
	int timer_init_reqd = 0;

	if (!is_hpet_enabled())
		return 0;

	if (!(PIE_on | AIE_on | UIE_on))
		timer_init_reqd = 1;

	if (bit_mask & RTC_UIE) {
		UIE_on = 1;
	}
	if (bit_mask & RTC_PIE) {
		PIE_on = 1;
		PIE_count = 0;
	}
	if (bit_mask & RTC_AIE) {
		AIE_on = 1;
	}

	if (timer_init_reqd)
		hpet_rtc_timer_init();

	return 1;
}

int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
{
	if (!is_hpet_enabled())
		return 0;

	alarm_time.tm_hour = hrs;
	alarm_time.tm_min = min;
	alarm_time.tm_sec = sec;

	return 1;
}

int hpet_set_periodic_freq(unsigned long freq)
{
	if (!is_hpet_enabled())
		return 0;

	PIE_freq = freq;
	PIE_count = 0;

	return 1;
}

int hpet_rtc_dropped_irq(void)
{
	if (!is_hpet_enabled())
		return 0;

	return 1;
}

irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct rtc_time curr_time;
	unsigned long rtc_int_flag = 0;
	int call_rtc_interrupt = 0;

	hpet_rtc_timer_reinit();

	if (UIE_on | AIE_on) {
		rtc_get_rtc_time(&curr_time);
	}
	if (UIE_on) {
		if (curr_time.tm_sec != prev_update_sec) {
			/* Set update int info, call real rtc int routine */
			call_rtc_interrupt = 1;
			rtc_int_flag = RTC_UF;
			prev_update_sec = curr_time.tm_sec;
		}
	}
	if (PIE_on) {
		PIE_count++;
		if (PIE_count >= hpet_rtc_int_freq/PIE_freq) {
			/* Set periodic int info, call real rtc int routine */
			call_rtc_interrupt = 1;
			rtc_int_flag |= RTC_PF;
			PIE_count = 0;
		}
	}
	if (AIE_on) {
		if ((curr_time.tm_sec == alarm_time.tm_sec) &&
		    (curr_time.tm_min == alarm_time.tm_min) &&
		    (curr_time.tm_hour == alarm_time.tm_hour)) {
			/* Set alarm int info, call real rtc int routine */
			call_rtc_interrupt = 1;
			rtc_int_flag |= RTC_AF;
		}
	}
	if (call_rtc_interrupt) {
		rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
		rtc_interrupt(rtc_int_flag, dev_id, regs);
	}
	return IRQ_HANDLED;
}
#endif



static int __init nohpet_setup(char *s) 
{ 
	nohpet = 1;
	return 0;
} 

__setup("nohpet", nohpet_setup);


static int __init notsc_setup(char *s)
{
	notsc = 1;
	return 0;
}

__setup("notsc", notsc_setup);