[deliverable/linux.git] / arch / i386 / kernel / time.c

/*
 *  linux/arch/i386/kernel/time.c
 *
 *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
 *
 * This file contains the PC-specific time handling details:
 * reading the RTC at bootup, etc..
 * 1994-07-02    Alan Modra
 *	fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
 * 1995-03-26    Markus Kuhn
 *      fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887
 *      precision CMOS clock update
 * 1996-05-03    Ingo Molnar
 *      fixed time warps in do_[slow|fast]_gettimeoffset()
 * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
 *		"A Kernel Model for Precision Timekeeping" by Dave Mills
 * 1998-09-05    (Various)
 *	More robust do_fast_gettimeoffset() algorithm implemented
 *	(works with APM, Cyrix 6x86MX and Centaur C6),
 *	monotonic gettimeofday() with fast_get_timeoffset(),
 *	drift-proof precision TSC calibration on boot
 *	(C. Scott Ananian <cananian@alumni.princeton.edu>, Andrew D.
 *	Balsa <andrebalsa@altern.org>, Philip Gladstone <philip@raptor.com>;
 *	ported from 2.0.35 Jumbo-9 by Michael Krause <m.krause@tu-harburg.de>).
 * 1998-12-16    Andrea Arcangeli
 *	Fixed Jumbo-9 code in 2.1.131: do_gettimeofday was missing 1 jiffy
 *	because was not accounting lost_ticks.
 * 1998-12-24 Copyright (C) 1998  Andrea Arcangeli
 *	Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
 *	serialize accesses to xtime/lost_ticks).
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/module.h>
#include <linux/sysdev.h>
#include <linux/bcd.h>
#include <linux/efi.h>
#include <linux/mca.h>

#include <asm/io.h>
#include <asm/smp.h>
#include <asm/irq.h>
#include <asm/msr.h>
#include <asm/delay.h>
#include <asm/mpspec.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
#include <asm/timer.h>

#include "mach_time.h"

#include <linux/timex.h>

#include <asm/hpet.h>

#include <asm/arch_hooks.h>

#include "io_ports.h"

#include <asm/i8259.h>

int pit_latch_buggy;              /* extern */

#include "do_timer.h"

unsigned int cpu_khz;	/* Detected as we calibrate the TSC */
EXPORT_SYMBOL(cpu_khz);

extern unsigned long wall_jiffies;

DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);

/*
 * This is a special lock that is owned by the CPU and holds the index
 * register we are working with.  It is required for NMI access to the
 * CMOS/RTC registers.  See include/asm-i386/mc146818rtc.h for details.
 */
volatile unsigned long cmos_lock = 0;
EXPORT_SYMBOL(cmos_lock);

/* Routines for accessing the CMOS RAM/RTC. */
unsigned char rtc_cmos_read(unsigned char addr)
{
	unsigned char val;
	lock_cmos_prefix(addr);
	outb_p(addr, RTC_PORT(0));
	val = inb_p(RTC_PORT(1));
	lock_cmos_suffix(addr);
	return val;
}
EXPORT_SYMBOL(rtc_cmos_read);

void rtc_cmos_write(unsigned char val, unsigned char addr)
{
	lock_cmos_prefix(addr);
	outb_p(addr, RTC_PORT(0));
	outb_p(val, RTC_PORT(1));
	lock_cmos_suffix(addr);
}
EXPORT_SYMBOL(rtc_cmos_write);

static int set_rtc_mmss(unsigned long nowtime)
{
	int retval;
	unsigned long flags;

	/* gets recalled with irq locally disabled */
	/* XXX - does irqsave resolve this? -johnstul */
	spin_lock_irqsave(&rtc_lock, flags);
	if (efi_enabled)
		retval = efi_set_rtc_mmss(nowtime);
	else
		retval = mach_set_rtc_mmss(nowtime);
	spin_unlock_irqrestore(&rtc_lock, flags);

	return retval;
}


int timer_ack;

#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
unsigned long profile_pc(struct pt_regs *regs)
{
	unsigned long pc = instruction_pointer(regs);

	if (!user_mode_vm(regs) && in_lock_functions(pc))
		return *(unsigned long *)(regs->ebp + 4);

	return pc;
}
EXPORT_SYMBOL(profile_pc);
#endif

/*
 * This is the same as the above, except we _also_ save the current
 * Time Stamp Counter value at the time of the timer interrupt, so that
 * we later on can estimate the time of day more exactly.
 */
irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	/*
	 * Here we are in the timer irq handler. We just have irqs locally
	 * disabled but we don't know if the timer_bh is running on the other
	 * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
	 * the irq version of write_lock because as just said we have irq
	 * locally disabled. -arca
	 */
	write_seqlock(&xtime_lock);

#ifdef CONFIG_X86_IO_APIC
	if (timer_ack) {
		/*
		 * Subtle, when I/O APICs are used we have to ack timer IRQ
		 * manually to reset the IRR bit for do_slow_gettimeoffset().
		 * This will also deassert NMI lines for the watchdog if run
		 * on an 82489DX-based system.
		 */
		spin_lock(&i8259A_lock);
		outb(0x0c, PIC_MASTER_OCW3);
		/* Ack the IRQ; AEOI will end it automatically. */
		inb(PIC_MASTER_POLL);
		spin_unlock(&i8259A_lock);
	}
#endif

	do_timer_interrupt_hook(regs);


	if (MCA_bus) {
		/* The PS/2 uses level-triggered interrupts.  You can't
		turn them off, nor would you want to (any attempt to
		enable edge-triggered interrupts usually gets intercepted by a
		special hardware circuit).  Hence we have to acknowledge
		the timer interrupt.  Through some incredibly stupid
		design idea, the reset for IRQ 0 is done by setting the
		high bit of the PPI port B (0x61).  Note that some PS/2s,
		notably the 55SX, work fine if this is removed.  */

		irq = inb_p( 0x61 );	/* read the current state */
		outb_p( irq|0x80, 0x61 );	/* reset the IRQ */
	}

	write_sequnlock(&xtime_lock);

#ifdef CONFIG_X86_LOCAL_APIC
	if (using_apic_timer)
		smp_send_timer_broadcast_ipi(regs);
#endif

	return IRQ_HANDLED;
}

/* not static: needed by APM */
unsigned long get_cmos_time(void)
{
	unsigned long retval;
	unsigned long flags;

	spin_lock_irqsave(&rtc_lock, flags);

	if (efi_enabled)
		retval = efi_get_time();
	else
		retval = mach_get_cmos_time();

	spin_unlock_irqrestore(&rtc_lock, flags);

	return retval;
}
EXPORT_SYMBOL(get_cmos_time);

static void sync_cmos_clock(unsigned long dummy);

static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);

static void sync_cmos_clock(unsigned long dummy)
{
	struct timeval now, next;
	int fail = 1;

	/*
	 * If we have an externally synchronized Linux clock, then update
	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
	 * called as close as possible to 500 ms before the new second starts.
	 * This code is run on a timer.  If the clock is set, that timer
	 * may not expire at the correct time.  Thus, we adjust...
	 */
	if (!ntp_synced())
		/*
		 * Not synced, exit, do not restart a timer (if one is
		 * running, let it run out).
		 */
		return;

	do_gettimeofday(&now);
	if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
	    now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
		fail = set_rtc_mmss(now.tv_sec);

	next.tv_usec = USEC_AFTER - now.tv_usec;
	if (next.tv_usec <= 0)
		next.tv_usec += USEC_PER_SEC;

	if (!fail)
		next.tv_sec = 659;
	else
		next.tv_sec = 0;

	if (next.tv_usec >= USEC_PER_SEC) {
		next.tv_sec++;
		next.tv_usec -= USEC_PER_SEC;
	}
	mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
}

void notify_arch_cmos_timer(void)
{
	mod_timer(&sync_cmos_timer, jiffies + 1);
}

static long clock_cmos_diff, sleep_start;

static int timer_suspend(struct sys_device *dev, pm_message_t state)
{
	/*
	 * Estimate time zone so that set_time can update the clock
	 */
	clock_cmos_diff = -get_cmos_time();
	clock_cmos_diff += get_seconds();
	sleep_start = get_cmos_time();
	return 0;
}

static int timer_resume(struct sys_device *dev)
{
	unsigned long flags;
	unsigned long sec;
	unsigned long sleep_length;

#ifdef CONFIG_HPET_TIMER
	if (is_hpet_enabled())
		hpet_reenable();
#endif
	setup_pit_timer();
	sec = get_cmos_time() + clock_cmos_diff;
	sleep_length = (get_cmos_time() - sleep_start) * HZ;
	write_seqlock_irqsave(&xtime_lock, flags);
	xtime.tv_sec = sec;
	xtime.tv_nsec = 0;
	jiffies_64 += sleep_length;
	wall_jiffies += sleep_length;
	write_sequnlock_irqrestore(&xtime_lock, flags);
	touch_softlockup_watchdog();
	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_TIMER
extern void (*late_time_init)(void);
/* Duplicate of time_init() below, with hpet_enable part added */
static void __init hpet_time_init(void)
{
	xtime.tv_sec = get_cmos_time();
	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
	set_normalized_timespec(&wall_to_monotonic,
		-xtime.tv_sec, -xtime.tv_nsec);

	if ((hpet_enable() >= 0) && hpet_use_timer) {
		printk("Using HPET for base-timer\n");
	}

	time_init_hook();
}
#endif

void __init time_init(void)
{
#ifdef CONFIG_HPET_TIMER
	if (is_hpet_capable()) {
		/*
		 * HPET initialization needs to do memory-mapped io. So, let
		 * us do a late initialization after mem_init().
		 */
		late_time_init = hpet_time_init;
		return;
	}
#endif
	xtime.tv_sec = get_cmos_time();
	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
	set_normalized_timespec(&wall_to_monotonic,
		-xtime.tv_sec, -xtime.tv_nsec);

	time_init_hook();
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/i386/kernel/time.c
	3	*
	4	* Copyright (C) 1991, 1992, 1995 Linus Torvalds
	5	*
	6	* This file contains the PC-specific time handling details:
	7	* reading the RTC at bootup, etc..
	8	* 1994-07-02 Alan Modra
	9	* fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
	10	* 1995-03-26 Markus Kuhn
	11	* fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887
	12	* precision CMOS clock update
	13	* 1996-05-03 Ingo Molnar
	14	* fixed time warps in do_[slow\|fast]_gettimeoffset()
	15	* 1997-09-10 Updated NTP code according to technical memorandum Jan '96
	16	* "A Kernel Model for Precision Timekeeping" by Dave Mills
	17	* 1998-09-05 (Various)
	18	* More robust do_fast_gettimeoffset() algorithm implemented
	19	* (works with APM, Cyrix 6x86MX and Centaur C6),
	20	* monotonic gettimeofday() with fast_get_timeoffset(),
	21	* drift-proof precision TSC calibration on boot
	22	* (C. Scott Ananian <cananian@alumni.princeton.edu>, Andrew D.
	23	* Balsa <andrebalsa@altern.org>, Philip Gladstone <philip@raptor.com>;
	24	* ported from 2.0.35 Jumbo-9 by Michael Krause <m.krause@tu-harburg.de>).
	25	* 1998-12-16 Andrea Arcangeli
	26	* Fixed Jumbo-9 code in 2.1.131: do_gettimeofday was missing 1 jiffy
	27	* because was not accounting lost_ticks.
	28	* 1998-12-24 Copyright (C) 1998 Andrea Arcangeli
	29	* Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
	30	* serialize accesses to xtime/lost_ticks).
	31	*/
	32
	33	#include <linux/errno.h>
	34	#include <linux/sched.h>
	35	#include <linux/kernel.h>
	36	#include <linux/param.h>
	37	#include <linux/string.h>
	38	#include <linux/mm.h>
	39	#include <linux/interrupt.h>
	40	#include <linux/time.h>
	41	#include <linux/delay.h>
	42	#include <linux/init.h>
	43	#include <linux/smp.h>
	44	#include <linux/module.h>
	45	#include <linux/sysdev.h>
	46	#include <linux/bcd.h>
	47	#include <linux/efi.h>
	48	#include <linux/mca.h>
	49
	50	#include <asm/io.h>
	51	#include <asm/smp.h>
	52	#include <asm/irq.h>
	53	#include <asm/msr.h>
	54	#include <asm/delay.h>
	55	#include <asm/mpspec.h>
	56	#include <asm/uaccess.h>
	57	#include <asm/processor.h>
	58	#include <asm/timer.h>
	59
	60	#include "mach_time.h"
	61
	62	#include <linux/timex.h>
1da177e4 LT	63
	64	#include <asm/hpet.h>
	65
	66	#include <asm/arch_hooks.h>
	67
	68	#include "io_ports.h"
	69
306e440d IM	70	#include <asm/i8259.h>
306e440d IM	71
1da177e4 LT	72	int pit_latch_buggy; /* extern */
	73
	74	#include "do_timer.h"
	75
a3a255e7	76	unsigned int cpu_khz; /* Detected as we calibrate the TSC */
129f6946	77	EXPORT_SYMBOL(cpu_khz);
1da177e4 LT	78
	79	extern unsigned long wall_jiffies;
	80
	81	DEFINE_SPINLOCK(rtc_lock);
129f6946	82	EXPORT_SYMBOL(rtc_lock);
1da177e4	83
1da177e4 LT	84	/*
	85	* This is a special lock that is owned by the CPU and holds the index
	86	* register we are working with. It is required for NMI access to the
	87	* CMOS/RTC registers. See include/asm-i386/mc146818rtc.h for details.
	88	*/
	89	volatile unsigned long cmos_lock = 0;
	90	EXPORT_SYMBOL(cmos_lock);
	91
	92	/* Routines for accessing the CMOS RAM/RTC. */
	93	unsigned char rtc_cmos_read(unsigned char addr)
	94	{
	95	unsigned char val;
	96	lock_cmos_prefix(addr);
	97	outb_p(addr, RTC_PORT(0));
	98	val = inb_p(RTC_PORT(1));
	99	lock_cmos_suffix(addr);
	100	return val;
	101	}
	102	EXPORT_SYMBOL(rtc_cmos_read);
	103
	104	void rtc_cmos_write(unsigned char val, unsigned char addr)
	105	{
	106	lock_cmos_prefix(addr);
	107	outb_p(addr, RTC_PORT(0));
	108	outb_p(val, RTC_PORT(1));
	109	lock_cmos_suffix(addr);
	110	}
	111	EXPORT_SYMBOL(rtc_cmos_write);
	112
1da177e4 LT	113	static int set_rtc_mmss(unsigned long nowtime)
	114	{
	115	int retval;
6f84fa2f	116	unsigned long flags;
1da177e4 LT	117
1da177e4 LT	118	/* gets recalled with irq locally disabled */
6f84fa2f	119	/* XXX - does irqsave resolve this? -johnstul */
6f84fa2f	120	spin_lock_irqsave(&rtc_lock, flags);
1da177e4 LT	121	if (efi_enabled)
	122	retval = efi_set_rtc_mmss(nowtime);
	123	else
	124	retval = mach_set_rtc_mmss(nowtime);
6f84fa2f	125	spin_unlock_irqrestore(&rtc_lock, flags);
1da177e4 LT	126
	127	return retval;
	128	}
	129
	130
	131	int timer_ack;
	132
1da177e4 LT	133	#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
	134	unsigned long profile_pc(struct pt_regs *regs)
	135	{
	136	unsigned long pc = instruction_pointer(regs);
	137
d5a26017	138	if (!user_mode_vm(regs) && in_lock_functions(pc))
1da177e4 LT	139	return (unsigned long )(regs->ebp + 4);
	140
	141	return pc;
	142	}
	143	EXPORT_SYMBOL(profile_pc);
	144	#endif
	145
	146	/*
6f84fa2f	147	* This is the same as the above, except we _also_ save the current
	148	* Time Stamp Counter value at the time of the timer interrupt, so that
	149	* we later on can estimate the time of day more exactly.
1da177e4	150	*/
6f84fa2f	151	irqreturn_t timer_interrupt(int irq, void dev_id, struct pt_regs regs)
1da177e4	152	{
6f84fa2f	153	/*
	154	* Here we are in the timer irq handler. We just have irqs locally
	155	* disabled but we don't know if the timer_bh is running on the other
	156	* CPU. We need to avoid to SMP race with it. NOTE: we don' t need
	157	* the irq version of write_lock because as just said we have irq
	158	* locally disabled. -arca
	159	*/
	160	write_seqlock(&xtime_lock);
	161
1da177e4 LT	162	#ifdef CONFIG_X86_IO_APIC
	163	if (timer_ack) {
	164	/*
	165	* Subtle, when I/O APICs are used we have to ack timer IRQ
	166	* manually to reset the IRR bit for do_slow_gettimeoffset().
	167	* This will also deassert NMI lines for the watchdog if run
	168	* on an 82489DX-based system.
	169	*/
	170	spin_lock(&i8259A_lock);
	171	outb(0x0c, PIC_MASTER_OCW3);
	172	/* Ack the IRQ; AEOI will end it automatically. */
	173	inb(PIC_MASTER_POLL);
	174	spin_unlock(&i8259A_lock);
	175	}
	176	#endif
	177
	178	do_timer_interrupt_hook(regs);
	179
	180
	181	if (MCA_bus) {
	182	/* The PS/2 uses level-triggered interrupts. You can't
	183	turn them off, nor would you want to (any attempt to
	184	enable edge-triggered interrupts usually gets intercepted by a
	185	special hardware circuit). Hence we have to acknowledge
	186	the timer interrupt. Through some incredibly stupid
	187	design idea, the reset for IRQ 0 is done by setting the
	188	high bit of the PPI port B (0x61). Note that some PS/2s,
	189	notably the 55SX, work fine if this is removed. */
	190
	191	irq = inb_p( 0x61 ); /* read the current state */
	192	outb_p( irq\|0x80, 0x61 ); /* reset the IRQ */
	193	}
1da177e4 LT	194
1da177e4 LT	195	write_sequnlock(&xtime_lock);
6eb0a0fd VP	196
	197	#ifdef CONFIG_X86_LOCAL_APIC
	198	if (using_apic_timer)
	199	smp_send_timer_broadcast_ipi(regs);
	200	#endif
	201
1da177e4 LT	202	return IRQ_HANDLED;
	203	}
	204
	205	/* not static: needed by APM */
	206	unsigned long get_cmos_time(void)
	207	{
	208	unsigned long retval;
7ba1c6c8	209	unsigned long flags;
1da177e4	210
7ba1c6c8	211	spin_lock_irqsave(&rtc_lock, flags);
1da177e4 LT	212
	213	if (efi_enabled)
	214	retval = efi_get_time();
	215	else
	216	retval = mach_get_cmos_time();
	217
7ba1c6c8	218	spin_unlock_irqrestore(&rtc_lock, flags);
1da177e4 LT	219
	220	return retval;
	221	}
129f6946 AD	222	EXPORT_SYMBOL(get_cmos_time);
129f6946 AD	223
1da177e4 LT	224	static void sync_cmos_clock(unsigned long dummy);
1da177e4 LT	225
8d06afab	226	static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
1da177e4 LT	227
	228	static void sync_cmos_clock(unsigned long dummy)
	229	{
	230	struct timeval now, next;
	231	int fail = 1;
	232
	233	/*
	234	* If we have an externally synchronized Linux clock, then update
	235	* CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
	236	* called as close as possible to 500 ms before the new second starts.
	237	* This code is run on a timer. If the clock is set, that timer
	238	* may not expire at the correct time. Thus, we adjust...
	239	*/
b149ee22	240	if (!ntp_synced())
1da177e4 LT	241	/*
	242	* Not synced, exit, do not restart a timer (if one is
	243	* running, let it run out).
	244	*/
	245	return;
	246
	247	do_gettimeofday(&now);
	248	if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
	249	now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
	250	fail = set_rtc_mmss(now.tv_sec);
	251
	252	next.tv_usec = USEC_AFTER - now.tv_usec;
	253	if (next.tv_usec <= 0)
	254	next.tv_usec += USEC_PER_SEC;
	255
	256	if (!fail)
	257	next.tv_sec = 659;
	258	else
	259	next.tv_sec = 0;
	260
	261	if (next.tv_usec >= USEC_PER_SEC) {
	262	next.tv_sec++;
	263	next.tv_usec -= USEC_PER_SEC;
	264	}
	265	mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
	266	}
	267
	268	void notify_arch_cmos_timer(void)
	269	{
	270	mod_timer(&sync_cmos_timer, jiffies + 1);
	271	}
	272
	273	static long clock_cmos_diff, sleep_start;
	274
438510f6	275	static int timer_suspend(struct sys_device *dev, pm_message_t state)
1da177e4 LT	276	{
	277	/*
	278	* Estimate time zone so that set_time can update the clock
	279	*/
	280	clock_cmos_diff = -get_cmos_time();
	281	clock_cmos_diff += get_seconds();
	282	sleep_start = get_cmos_time();
	283	return 0;
	284	}
	285
	286	static int timer_resume(struct sys_device *dev)
	287	{
	288	unsigned long flags;
	289	unsigned long sec;
	290	unsigned long sleep_length;
	291
	292	#ifdef CONFIG_HPET_TIMER
	293	if (is_hpet_enabled())
	294	hpet_reenable();
	295	#endif
c3c433e4	296	setup_pit_timer();
1da177e4 LT	297	sec = get_cmos_time() + clock_cmos_diff;
	298	sleep_length = (get_cmos_time() - sleep_start) * HZ;
	299	write_seqlock_irqsave(&xtime_lock, flags);
	300	xtime.tv_sec = sec;
	301	xtime.tv_nsec = 0;
f7c09bd9	302	jiffies_64 += sleep_length;
1da177e4	303	wall_jiffies += sleep_length;
f7c09bd9	304	write_sequnlock_irqrestore(&xtime_lock, flags);
8446f1d3	305	touch_softlockup_watchdog();
1da177e4 LT	306	return 0;
	307	}
	308
	309	static struct sysdev_class timer_sysclass = {
	310	.resume = timer_resume,
	311	.suspend = timer_suspend,
	312	set_kset_name("timer"),
	313	};
	314
	315
	316	/* XXX this driverfs stuff should probably go elsewhere later -john */
	317	static struct sys_device device_timer = {
	318	.id = 0,
	319	.cls = &timer_sysclass,
	320	};
	321
	322	static int time_init_device(void)
	323	{
	324	int error = sysdev_class_register(&timer_sysclass);
	325	if (!error)
	326	error = sysdev_register(&device_timer);
	327	return error;
	328	}
	329
	330	device_initcall(time_init_device);
	331
f2b36db6	332	#ifdef CONFIG_HPET_TIMER
1e4c85f9	333	extern void (*late_time_init)(void);
1da177e4 LT	334	/* Duplicate of time_init() below, with hpet_enable part added */
	335	static void __init hpet_time_init(void)
	336	{
	337	xtime.tv_sec = get_cmos_time();
	338	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
	339	set_normalized_timespec(&wall_to_monotonic,
	340	-xtime.tv_sec, -xtime.tv_nsec);
	341
35492df5	342	if ((hpet_enable() >= 0) && hpet_use_timer) {
1da177e4 LT	343	printk("Using HPET for base-timer\n");
	344	}
	345
1da177e4 LT	346	time_init_hook();
	347	}
	348	#endif
	349
	350	void __init time_init(void)
	351	{
	352	#ifdef CONFIG_HPET_TIMER
	353	if (is_hpet_capable()) {
	354	/*
	355	* HPET initialization needs to do memory-mapped io. So, let
	356	* us do a late initialization after mem_init().
	357	*/
	358	late_time_init = hpet_time_init;
	359	return;
	360	}
	361	#endif
	362	xtime.tv_sec = get_cmos_time();
	363	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
	364	set_normalized_timespec(&wall_to_monotonic,
	365	-xtime.tv_sec, -xtime.tv_nsec);
	366
1da177e4 LT	367	time_init_hook();
1da177e4 LT	368	}