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Diffstat (limited to 'arch/x86/kernel/tsc_32.c')
-rw-r--r--arch/x86/kernel/tsc_32.c188
1 files changed, 0 insertions, 188 deletions
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c
deleted file mode 100644
index bbc153d36f8..00000000000
--- a/arch/x86/kernel/tsc_32.c
+++ /dev/null
@@ -1,188 +0,0 @@
-#include <linux/sched.h>
-#include <linux/clocksource.h>
-#include <linux/workqueue.h>
-#include <linux/delay.h>
-#include <linux/cpufreq.h>
-#include <linux/jiffies.h>
-#include <linux/init.h>
-#include <linux/dmi.h>
-#include <linux/percpu.h>
-
-#include <asm/delay.h>
-#include <asm/tsc.h>
-#include <asm/io.h>
-#include <asm/timer.h>
-
-#include "mach_timer.h"
-
-extern int tsc_unstable;
-extern int tsc_disabled;
-
-/* clock source code */
-
-static struct clocksource clocksource_tsc;
-
-/*
- * We compare the TSC to the cycle_last value in the clocksource
- * structure to avoid a nasty time-warp issue. This can be observed in
- * a very small window right after one CPU updated cycle_last under
- * xtime 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;
-
- rdtscll(ret);
-
- return ret >= clocksource_tsc.cycle_last ?
- ret : clocksource_tsc.cycle_last;
-}
-
-static struct clocksource clocksource_tsc = {
- .name = "tsc",
- .rating = 300,
- .read = read_tsc,
- .mask = CLOCKSOURCE_MASK(64),
- .mult = 0, /* to be set */
- .shift = 22,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS |
- CLOCK_SOURCE_MUST_VERIFY,
-};
-
-void mark_tsc_unstable(char *reason)
-{
- if (!tsc_unstable) {
- tsc_unstable = 1;
- printk("Marking TSC unstable due to: %s.\n", reason);
- /* Can be called before registration */
- if (clocksource_tsc.mult)
- clocksource_change_rating(&clocksource_tsc, 0);
- else
- clocksource_tsc.rating = 0;
- }
-}
-EXPORT_SYMBOL_GPL(mark_tsc_unstable);
-
-static int __init dmi_mark_tsc_unstable(const struct dmi_system_id *d)
-{
- printk(KERN_NOTICE "%s detected: marking TSC unstable.\n",
- d->ident);
- tsc_unstable = 1;
- return 0;
-}
-
-/* List of systems that have known TSC problems */
-static struct dmi_system_id __initdata bad_tsc_dmi_table[] = {
- {
- .callback = dmi_mark_tsc_unstable,
- .ident = "IBM Thinkpad 380XD",
- .matches = {
- DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
- DMI_MATCH(DMI_BOARD_NAME, "2635FA0"),
- },
- },
- {}
-};
-
-/*
- * Make an educated guess if the TSC is trustworthy and synchronized
- * over all CPUs.
- */
-__cpuinit int unsynchronized_tsc(void)
-{
- if (!cpu_has_tsc || tsc_unstable)
- return 1;
-
- /* Anything with constant TSC should be synchronized */
- if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- /*
- * Intel systems are normally all synchronized.
- * Exceptions must mark TSC as unstable:
- */
- if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
- /* assume multi socket systems are not synchronized: */
- if (num_possible_cpus() > 1)
- tsc_unstable = 1;
- }
- return tsc_unstable;
-}
-
-/*
- * Geode_LX - the OLPC CPU has a possibly a very reliable TSC
- */
-#ifdef CONFIG_MGEODE_LX
-/* RTSC counts during suspend */
-#define RTSC_SUSP 0x100
-
-static void __init check_geode_tsc_reliable(void)
-{
- unsigned long res_low, res_high;
-
- rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
- if (res_low & RTSC_SUSP)
- clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY;
-}
-#else
-static inline void check_geode_tsc_reliable(void) { }
-#endif
-
-
-void __init tsc_init(void)
-{
- int cpu;
- u64 lpj;
-
- if (!cpu_has_tsc || tsc_disabled > 0)
- return;
-
- cpu_khz = calculate_cpu_khz();
- tsc_khz = cpu_khz;
-
- if (!cpu_khz) {
- mark_tsc_unstable("could not calculate TSC khz");
- return;
- }
-
- lpj = ((u64)tsc_khz * 1000);
- do_div(lpj, HZ);
- lpj_fine = lpj;
-
- /* now allow native_sched_clock() to use rdtsc */
- tsc_disabled = 0;
-
- printk("Detected %lu.%03lu MHz processor.\n",
- (unsigned long)cpu_khz / 1000,
- (unsigned long)cpu_khz % 1000);
-
- /*
- * Secondary CPUs do not run through tsc_init(), so set up
- * all the scale factors for all CPUs, assuming the same
- * speed as the bootup CPU. (cpufreq notifiers will fix this
- * up if their speed diverges)
- */
- for_each_possible_cpu(cpu)
- set_cyc2ns_scale(cpu_khz, cpu);
-
- use_tsc_delay();
-
- /* Check and install the TSC clocksource */
- dmi_check_system(bad_tsc_dmi_table);
-
- unsynchronized_tsc();
- check_geode_tsc_reliable();
- clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
- clocksource_tsc.shift);
- /* lower the rating if we already know its unstable: */
- if (check_tsc_unstable()) {
- clocksource_tsc.rating = 0;
- clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
- }
- clocksource_register(&clocksource_tsc);
-}