Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 476 insertions, 0 deletions

diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
new file mode 100644
index 0000000..9b55e30
--- /dev/null
+++ b/arch/i386/kernel/time.c
@@ -0,0 +1,476 @@
+/*
+ *  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 <linux/config.h>
+
+#include <asm/hpet.h>
+
+#include <asm/arch_hooks.h>
+
+#include "io_ports.h"
+
+extern spinlock_t i8259A_lock;
+int pit_latch_buggy;              /* extern */
+
+#include "do_timer.h"
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+unsigned long cpu_khz;	/* Detected as we calibrate the TSC */
+
+extern unsigned long wall_jiffies;
+
+DEFINE_SPINLOCK(rtc_lock);
+
+DEFINE_SPINLOCK(i8253_lock);
+EXPORT_SYMBOL(i8253_lock);
+
+struct timer_opts *cur_timer = &timer_none;
+
+/*
+ * 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);
+
+/*
+ * This version of gettimeofday has microsecond resolution
+ * and better than microsecond precision on fast x86 machines with TSC.
+ */
+void do_gettimeofday(struct timeval *tv)
+{
+	unsigned long seq;
+	unsigned long usec, sec;
+	unsigned long max_ntp_tick;
+
+	do {
+		unsigned long lost;
+
+		seq = read_seqbegin(&xtime_lock);
+
+		usec = cur_timer->get_offset();
+		lost = jiffies - wall_jiffies;
+
+		/*
+		 * If time_adjust is negative then NTP is slowing the clock
+		 * so make sure not to go into next possible interval.
+		 * Better to lose some accuracy than have time go backwards..
+		 */
+		if (unlikely(time_adjust < 0)) {
+			max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj;
+			usec = min(usec, max_ntp_tick);
+
+			if (lost)
+				usec += lost * max_ntp_tick;
+		}
+		else if (unlikely(lost))
+			usec += lost * (USEC_PER_SEC / HZ);
+
+		sec = xtime.tv_sec;
+		usec += (xtime.tv_nsec / 1000);
+	} while (read_seqretry(&xtime_lock, seq));
+
+	while (usec >= 1000000) {
+		usec -= 1000000;
+		sec++;
+	}
+
+	tv->tv_sec = sec;
+	tv->tv_usec = usec;
+}
+
+EXPORT_SYMBOL(do_gettimeofday);
+
+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);
+	/*
+	 * This is revolting. We need to set "xtime" correctly. However, the
+	 * value in this location is the value at the most recent update of
+	 * wall time.  Discover what correction gettimeofday() would have
+	 * made, and then undo it!
+	 */
+	nsec -= cur_timer->get_offset() * NSEC_PER_USEC;
+	nsec -= (jiffies - wall_jiffies) * TICK_NSEC;
+
+	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);
+
+	time_adjust = 0;		/* stop active adjtime() */
+	time_status |= STA_UNSYNC;
+	time_maxerror = NTP_PHASE_LIMIT;
+	time_esterror = NTP_PHASE_LIMIT;
+	write_sequnlock_irq(&xtime_lock);
+	clock_was_set();
+	return 0;
+}
+
+EXPORT_SYMBOL(do_settimeofday);
+
+static int set_rtc_mmss(unsigned long nowtime)
+{
+	int retval;
+
+	WARN_ON(irqs_disabled());
+
+	/* gets recalled with irq locally disabled */
+	spin_lock_irq(&rtc_lock);
+	if (efi_enabled)
+		retval = efi_set_rtc_mmss(nowtime);
+	else
+		retval = mach_set_rtc_mmss(nowtime);
+	spin_unlock_irq(&rtc_lock);
+
+	return retval;
+}
+
+
+int timer_ack;
+
+/* 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)
+{
+	return cur_timer->monotonic_clock();
+}
+EXPORT_SYMBOL(monotonic_clock);
+
+#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
+unsigned long profile_pc(struct pt_regs *regs)
+{
+	unsigned long pc = instruction_pointer(regs);
+
+	if (in_lock_functions(pc))
+		return *(unsigned long *)(regs->ebp + 4);
+
+	return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+#endif
+
+/*
+ * timer_interrupt() needs to keep up the real-time clock,
+ * as well as call the "do_timer()" routine every clocktick
+ */
+static inline void do_timer_interrupt(int irq, void *dev_id,
+					struct pt_regs *regs)
+{
+#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 */
+	}
+}
+
+/*
+ * 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);
+
+	cur_timer->mark_offset();
+ 
+	do_timer_interrupt(irq, NULL, regs);
+
+	write_sequnlock(&xtime_lock);
+	return IRQ_HANDLED;
+}
+
+/* not static: needed by APM */
+unsigned long get_cmos_time(void)
+{
+	unsigned long retval;
+
+	spin_lock(&rtc_lock);
+
+	if (efi_enabled)
+		retval = efi_get_time();
+	else
+		retval = mach_get_cmos_time();
+
+	spin_unlock(&rtc_lock);
+
+	return retval;
+}
+static void sync_cmos_clock(unsigned long dummy);
+
+static struct timer_list sync_cmos_timer =
+                                      TIMER_INITIALIZER(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 ((time_status & STA_UNSYNC) != 0)
+		/*
+		 * 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, u32 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
+	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;
+	write_sequnlock_irqrestore(&xtime_lock, flags);
+	jiffies += sleep_length;
+	wall_jiffies += sleep_length;
+	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) {
+		printk("Using HPET for base-timer\n");
+	}
+
+	cur_timer = select_timer();
+	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
+
+	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);
+
+	cur_timer = select_timer();
+	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
+
+	time_init_hook();
+}