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-rw-r--r--arch/x86/kernel/tsc_64.c357
1 files changed, 0 insertions, 357 deletions
diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c
deleted file mode 100644
index 1784b80..0000000
--- a/arch/x86/kernel/tsc_64.c
+++ /dev/null
@@ -1,357 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/init.h>
-#include <linux/clocksource.h>
-#include <linux/time.h>
-#include <linux/acpi.h>
-#include <linux/cpufreq.h>
-#include <linux/acpi_pmtmr.h>
-
-#include <asm/hpet.h>
-#include <asm/timex.h>
-#include <asm/timer.h>
-#include <asm/vgtod.h>
-
-static int notsc __initdata = 0;
-
-unsigned int cpu_khz; /* TSC clocks / usec, not used here */
-EXPORT_SYMBOL(cpu_khz);
-unsigned int tsc_khz;
-EXPORT_SYMBOL(tsc_khz);
-
-/* Accelerators for sched_clock()
- * convert from cycles(64bits) => nanoseconds (64bits)
- * basic equation:
- * ns = cycles / (freq / ns_per_sec)
- * ns = cycles * (ns_per_sec / freq)
- * ns = cycles * (10^9 / (cpu_khz * 10^3))
- * ns = cycles * (10^6 / cpu_khz)
- *
- * Then we use scaling math (suggested by george@mvista.com) to get:
- * ns = cycles * (10^6 * SC / cpu_khz) / SC
- * ns = cycles * cyc2ns_scale / SC
- *
- * And since SC is a constant power of two, we can convert the div
- * into a shift.
- *
- * We can use khz divisor instead of mhz to keep a better precision, since
- * cyc2ns_scale is limited to 10^6 * 2^10, which fits in 32 bits.
- * (mathieu.desnoyers@polymtl.ca)
- *
- * -johnstul@us.ibm.com "math is hard, lets go shopping!"
- */
-DEFINE_PER_CPU(unsigned long, cyc2ns);
-
-static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
-{
- unsigned long long tsc_now, ns_now;
- unsigned long flags, *scale;
-
- local_irq_save(flags);
- sched_clock_idle_sleep_event();
-
- scale = &per_cpu(cyc2ns, cpu);
-
- rdtscll(tsc_now);
- ns_now = __cycles_2_ns(tsc_now);
-
- if (cpu_khz)
- *scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
-
- sched_clock_idle_wakeup_event(0);
- local_irq_restore(flags);
-}
-
-unsigned long long native_sched_clock(void)
-{
- unsigned long a = 0;
-
- /* 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);
-}
-
-/* We need to define a real function for sched_clock, to override the
- weak default version */
-#ifdef CONFIG_PARAVIRT
-unsigned long long sched_clock(void)
-{
- return paravirt_sched_clock();
-}
-#else
-unsigned long long
-sched_clock(void) __attribute__((alias("native_sched_clock")));
-#endif
-
-
-static int tsc_unstable;
-
-int check_tsc_unstable(void)
-{
- return tsc_unstable;
-}
-EXPORT_SYMBOL_GPL(check_tsc_unstable);
-
-#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.
- */
-
-static unsigned int ref_freq;
-static unsigned long loops_per_jiffy_ref;
-static unsigned long tsc_khz_ref;
-
-static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
- void *data)
-{
- struct cpufreq_freqs *freq = data;
- unsigned long *lpj, dummy;
-
- if (cpu_has(&cpu_data(freq->cpu), X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- 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;
- tsc_khz_ref = tsc_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);
-
- tsc_khz = cpufreq_scale(tsc_khz_ref, ref_freq, freq->new);
- if (!(freq->flags & CPUFREQ_CONST_LOOPS))
- mark_tsc_unstable("cpufreq changes");
- }
-
- set_cyc2ns_scale(tsc_khz_ref, freq->cpu);
-
- return 0;
-}
-
-static struct notifier_block time_cpufreq_notifier_block = {
- .notifier_call = time_cpufreq_notifier
-};
-
-static int __init cpufreq_tsc(void)
-{
- cpufreq_register_notifier(&time_cpufreq_notifier_block,
- CPUFREQ_TRANSITION_NOTIFIER);
- return 0;
-}
-
-core_initcall(cpufreq_tsc);
-
-#endif
-
-#define MAX_RETRIES 5
-#define SMI_TRESHOLD 50000
-
-/*
- * Read TSC and the reference counters. Take care of SMI disturbance
- */
-static unsigned long __init tsc_read_refs(unsigned long *pm,
- unsigned long *hpet)
-{
- unsigned long t1, t2;
- int i;
-
- for (i = 0; i < MAX_RETRIES; i++) {
- t1 = get_cycles();
- if (hpet)
- *hpet = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF;
- else
- *pm = acpi_pm_read_early();
- t2 = get_cycles();
- if ((t2 - t1) < SMI_TRESHOLD)
- return t2;
- }
- return ULONG_MAX;
-}
-
-/**
- * tsc_calibrate - calibrate the tsc on boot
- */
-void __init tsc_calibrate(void)
-{
- unsigned long flags, tsc1, tsc2, tr1, tr2, pm1, pm2, hpet1, hpet2;
- int hpet = is_hpet_enabled(), cpu;
-
- local_irq_save(flags);
-
- tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL);
-
- outb((inb(0x61) & ~0x02) | 0x01, 0x61);
-
- outb(0xb0, 0x43);
- outb((CLOCK_TICK_RATE / (1000 / 50)) & 0xff, 0x42);
- outb((CLOCK_TICK_RATE / (1000 / 50)) >> 8, 0x42);
- tr1 = get_cycles();
- while ((inb(0x61) & 0x20) == 0);
- tr2 = get_cycles();
-
- tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL);
-
- local_irq_restore(flags);
-
- /*
- * Preset the result with the raw and inaccurate PIT
- * calibration value
- */
- tsc_khz = (tr2 - tr1) / 50;
-
- /* hpet or pmtimer available ? */
- if (!hpet && !pm1 && !pm2) {
- printk(KERN_INFO "TSC calibrated against PIT\n");
- goto out;
- }
-
- /* Check, whether the sampling was disturbed by an SMI */
- if (tsc1 == ULONG_MAX || tsc2 == ULONG_MAX) {
- printk(KERN_WARNING "TSC calibration disturbed by SMI, "
- "using PIT calibration result\n");
- goto out;
- }
-
- tsc2 = (tsc2 - tsc1) * 1000000L;
-
- if (hpet) {
- printk(KERN_INFO "TSC calibrated against HPET\n");
- if (hpet2 < hpet1)
- hpet2 += 0x100000000;
- hpet2 -= hpet1;
- tsc1 = (hpet2 * hpet_readl(HPET_PERIOD)) / 1000000;
- } else {
- printk(KERN_INFO "TSC calibrated against PM_TIMER\n");
- if (pm2 < pm1)
- pm2 += ACPI_PM_OVRRUN;
- pm2 -= pm1;
- tsc1 = (pm2 * 1000000000) / PMTMR_TICKS_PER_SEC;
- }
-
- tsc_khz = tsc2 / tsc1;
-
-out:
- for_each_possible_cpu(cpu)
- set_cyc2ns_scale(tsc_khz, cpu);
-}
-
-/*
- * Make an educated guess if the TSC is trustworthy and synchronized
- * over all CPUs.
- */
-__cpuinit int unsynchronized_tsc(void)
-{
- if (tsc_unstable)
- return 1;
-
-#ifdef CONFIG_SMP
- if (apic_is_clustered_box())
- return 1;
-#endif
-
- if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- /* Assume multi socket systems are not synchronized */
- return num_present_cpus() > 1;
-}
-
-int __init notsc_setup(char *s)
-{
- notsc = 1;
- return 1;
-}
-
-__setup("notsc", notsc_setup);
-
-static struct clocksource clocksource_tsc;
-
-/*
- * We compare the TSC to the cycle_last value in the clocksource
- * structure to avoid a nasty time-warp. This can be observed in a
- * very small window right after one CPU updated cycle_last under
- * xtime/vsyscall_gtod lock and the other CPU reads a TSC value which
- * is smaller than the cycle_last reference value due to a TSC which
- * is slighty behind. This delta is nowhere else observable, but in
- * that case it results in a forward time jump in the range of hours
- * due to the unsigned delta calculation of the time keeping core
- * code, which is necessary to support wrapping clocksources like pm
- * timer.
- */
-static cycle_t read_tsc(void)
-{
- cycle_t ret = (cycle_t)get_cycles();
-
- return ret >= clocksource_tsc.cycle_last ?
- ret : clocksource_tsc.cycle_last;
-}
-
-static cycle_t __vsyscall_fn vread_tsc(void)
-{
- cycle_t ret = (cycle_t)vget_cycles();
-
- return ret >= __vsyscall_gtod_data.clock.cycle_last ?
- ret : __vsyscall_gtod_data.clock.cycle_last;
-}
-
-static struct clocksource clocksource_tsc = {
- .name = "tsc",
- .rating = 300,
- .read = read_tsc,
- .mask = CLOCKSOURCE_MASK(64),
- .shift = 22,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS |
- CLOCK_SOURCE_MUST_VERIFY,
- .vread = vread_tsc,
-};
-
-void mark_tsc_unstable(char *reason)
-{
- if (!tsc_unstable) {
- tsc_unstable = 1;
- printk("Marking TSC unstable due to %s\n", reason);
- /* Change only the rating, when not registered */
- if (clocksource_tsc.mult)
- clocksource_change_rating(&clocksource_tsc, 0);
- else
- clocksource_tsc.rating = 0;
- }
-}
-EXPORT_SYMBOL_GPL(mark_tsc_unstable);
-
-void __init init_tsc_clocksource(void)
-{
- if (!notsc) {
- clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
- clocksource_tsc.shift);
- if (check_tsc_unstable())
- clocksource_tsc.rating = 0;
-
- clocksource_register(&clocksource_tsc);
- }
-}
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