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authorThomas Gleixner <tglx@linutronix.de>2007-10-11 11:14:54 +0200
committerThomas Gleixner <tglx@linutronix.de>2007-10-11 11:14:54 +0200
commitabb11834c6515161babea211a7be1fc6dcb893dc (patch)
tree0c3101e18acd60aea9454e7bb26df1db96257de2 /arch/x86_64/kernel/time.c
parent96a6674c5ad6a6f596aab6ac826b93f5cd846749 (diff)
downloadlinux-abb11834c6515161babea211a7be1fc6dcb893dc.tar.gz
x86_64: prepare shared kernel/time.c
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86_64/kernel/time.c')
-rw-r--r--arch/x86_64/kernel/time.c447
1 files changed, 0 insertions, 447 deletions
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
deleted file mode 100644
index 6d48a4e826d9d1..00000000000000
--- a/arch/x86_64/kernel/time.c
+++ /dev/null
@@ -1,447 +0,0 @@
-/*
- * 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) 2002,2006 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/notifier.h>
-#include <linux/cpu.h>
-#include <linux/kallsyms.h>
-#include <linux/acpi.h>
-#ifdef CONFIG_ACPI
-#include <acpi/achware.h> /* for PM timer frequency */
-#include <acpi/acpi_bus.h>
-#endif
-#include <asm/8253pit.h>
-#include <asm/i8253.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/hpet.h>
-#include <asm/apic.h>
-#include <asm/hpet.h>
-#include <asm/mpspec.h>
-#include <asm/nmi.h>
-#include <asm/vgtod.h>
-
-static char *timename = NULL;
-
-DEFINE_SPINLOCK(rtc_lock);
-EXPORT_SYMBOL(rtc_lock);
-DEFINE_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
-volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
-
-unsigned long profile_pc(struct pt_regs *regs)
-{
- unsigned long pc = instruction_pointer(regs);
-
- /* Assume the lock function has either no stack frame or a copy
- of eflags from PUSHF
- Eflags always has bits 22 and up cleared unlike kernel addresses. */
- if (!user_mode(regs) && in_lock_functions(pc)) {
- unsigned long *sp = (unsigned long *)regs->rsp;
- if (sp[0] >> 22)
- return sp[0];
- if (sp[1] >> 22)
- return sp[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 int set_rtc_mmss(unsigned long nowtime)
-{
- int retval = 0;
- 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 (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);
- retval = -1;
- } else {
- 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);
-
- return retval;
-}
-
-int update_persistent_clock(struct timespec now)
-{
- return set_rtc_mmss(now.tv_sec);
-}
-
-void main_timer_handler(void)
-{
-/*
- * 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);
-
-/*
- * Do the timer stuff.
- */
-
- do_timer(1);
-#ifndef CONFIG_SMP
- update_process_times(user_mode(get_irq_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.
- */
-
- if (!using_apic_timer)
- smp_local_timer_interrupt();
-
- write_sequnlock(&xtime_lock);
-}
-
-static irqreturn_t timer_interrupt(int irq, void *dev_id)
-{
- if (apic_runs_main_timer > 1)
- return IRQ_HANDLED;
- main_timer_handler();
- if (using_apic_timer)
- smp_send_timer_broadcast_ipi();
- return IRQ_HANDLED;
-}
-
-unsigned long read_persistent_clock(void)
-{
- unsigned int year, mon, day, hour, min, sec;
- unsigned long flags;
- unsigned century = 0;
-
- spin_lock_irqsave(&rtc_lock, flags);
-
- do {
- 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);
-#ifdef CONFIG_ACPI
- if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
- acpi_gbl_FADT.century)
- century = CMOS_READ(acpi_gbl_FADT.century);
-#endif
- } while (sec != CMOS_READ(RTC_SECONDS));
-
- 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);
-
- if (century) {
- BCD_TO_BIN(century);
- year += century * 100;
- printk(KERN_INFO "Extended CMOS year: %d\n", century * 100);
- } else {
- /*
- * 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);
-}
-
-/* calibrate_cpu is used on systems with fixed rate TSCs to determine
- * processor frequency */
-#define TICK_COUNT 100000000
-static unsigned int __init tsc_calibrate_cpu_khz(void)
-{
- int tsc_start, tsc_now;
- int i, no_ctr_free;
- unsigned long evntsel3 = 0, pmc3 = 0, pmc_now = 0;
- unsigned long flags;
-
- for (i = 0; i < 4; i++)
- if (avail_to_resrv_perfctr_nmi_bit(i))
- break;
- no_ctr_free = (i == 4);
- if (no_ctr_free) {
- i = 3;
- rdmsrl(MSR_K7_EVNTSEL3, evntsel3);
- wrmsrl(MSR_K7_EVNTSEL3, 0);
- rdmsrl(MSR_K7_PERFCTR3, pmc3);
- } else {
- reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i);
- reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
- }
- local_irq_save(flags);
- /* start meauring cycles, incrementing from 0 */
- wrmsrl(MSR_K7_PERFCTR0 + i, 0);
- wrmsrl(MSR_K7_EVNTSEL0 + i, 1 << 22 | 3 << 16 | 0x76);
- rdtscl(tsc_start);
- do {
- rdmsrl(MSR_K7_PERFCTR0 + i, pmc_now);
- tsc_now = get_cycles_sync();
- } while ((tsc_now - tsc_start) < TICK_COUNT);
-
- local_irq_restore(flags);
- if (no_ctr_free) {
- wrmsrl(MSR_K7_EVNTSEL3, 0);
- wrmsrl(MSR_K7_PERFCTR3, pmc3);
- wrmsrl(MSR_K7_EVNTSEL3, evntsel3);
- } else {
- release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
- release_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
- }
-
- return pmc_now * tsc_khz / (tsc_now - tsc_start);
-}
-
-/*
- * 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);
- start = get_cycles_sync();
- while ((inb(0x61) & 0x20) == 0);
- end = get_cycles_sync();
-
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- return (end - start) / 50;
-}
-
-#define PIT_MODE 0x43
-#define PIT_CH0 0x40
-
-static void __pit_init(int val, u8 mode)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&i8253_lock, flags);
- outb_p(mode, PIT_MODE);
- outb_p(val & 0xff, PIT_CH0); /* LSB */
- outb_p(val >> 8, PIT_CH0); /* MSB */
- spin_unlock_irqrestore(&i8253_lock, flags);
-}
-
-void __init pit_init(void)
-{
- __pit_init(LATCH, 0x34); /* binary, mode 2, LSB/MSB, ch 0 */
-}
-
-void pit_stop_interrupt(void)
-{
- __pit_init(0, 0x30); /* mode 0 */
-}
-
-void stop_timer_interrupt(void)
-{
- char *name;
- if (hpet_address) {
- name = "HPET";
- hpet_timer_stop_set_go(0);
- } else {
- name = "PIT";
- pit_stop_interrupt();
- }
- printk(KERN_INFO "timer: %s interrupt stopped.\n", name);
-}
-
-static struct irqaction irq0 = {
- .handler = timer_interrupt,
- .flags = IRQF_DISABLED | IRQF_IRQPOLL,
- .mask = CPU_MASK_NONE,
- .name = "timer"
-};
-
-void __init time_init(void)
-{
- if (nohpet)
- hpet_address = 0;
-
- if (hpet_arch_init())
- hpet_address = 0;
-
- if (hpet_use_timer) {
- /* set tick_nsec to use the proper rate for HPET */
- tick_nsec = TICK_NSEC_HPET;
- tsc_khz = hpet_calibrate_tsc();
- timename = "HPET";
- } else {
- pit_init();
- tsc_khz = pit_calibrate_tsc();
- timename = "PIT";
- }
-
- cpu_khz = tsc_khz;
- if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
- boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
- boot_cpu_data.x86 == 16)
- cpu_khz = tsc_calibrate_cpu_khz();
-
- if (unsynchronized_tsc())
- mark_tsc_unstable("TSCs unsynchronized");
-
- if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
- vgetcpu_mode = VGETCPU_RDTSCP;
- else
- vgetcpu_mode = VGETCPU_LSL;
-
- set_cyc2ns_scale(tsc_khz);
- printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
- cpu_khz / 1000, cpu_khz % 1000);
- init_tsc_clocksource();
-
- setup_irq(0, &irq0);
-}
-
-/*
- * sysfs support for the timer.
- */
-
-static int timer_suspend(struct sys_device *dev, pm_message_t state)
-{
- return 0;
-}
-
-static int timer_resume(struct sys_device *dev)
-{
- if (hpet_address)
- hpet_reenable();
- else
- i8254_timer_resume();
- return 0;
-}
-
-static struct sysdev_class timer_sysclass = {
- .resume = timer_resume,
- .suspend = timer_suspend,
- set_kset_name("timer"),
-};
-
-/* XXX this sysfs 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);