2 files changed, 27 insertions, 50 deletions

diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c
index 23b780b121e1..4b66d10cb5ae 100644
--- a/sys/x86/x86/local_apic.c
+++ b/sys/x86/x86/local_apic.c
@@ -56,6 +56,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/smp.h>
 #include <sys/sysctl.h>
 #include <sys/timeet.h>
+#include <sys/timetc.h>
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
@@ -64,6 +65,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/clock.h>
 #include <machine/cpufunc.h>
 #include <machine/cputypes.h>
+#include <machine/fpu.h>
 #include <machine/frame.h>
 #include <machine/intr_machdep.h>
 #include <x86/apicvar.h>
@@ -1000,30 +1002,39 @@ native_lapic_disable_pmc(void)
 #endif
 }
 
+static uint64_t
+cb_lapic_getcount(void)
+{
+
+	return (APIC_TIMER_MAX_COUNT - lapic_read32(LAPIC_CCR_TIMER));
+}
+
 static void
 lapic_calibrate_initcount(struct lapic *la)
 {
-	u_long value;
+	uint64_t freq;
+
+	/* Calibrate the APIC timer frequency. */
+	lapic_timer_set_divisor(2);
+	lapic_timer_oneshot_nointr(la, APIC_TIMER_MAX_COUNT);
+	fpu_kern_enter(curthread, NULL, FPU_KERN_NOCTX);
+	freq = clockcalib(cb_lapic_getcount, "lapic");
+	fpu_kern_leave(curthread, NULL);
 
-	/* Start off with a divisor of 2 (power on reset default). */
+	/* Pick a different divisor if necessary. */
 	lapic_timer_divisor = 2;
-	/* Try to calibrate the local APIC timer. */
 	do {
-		lapic_timer_set_divisor(lapic_timer_divisor);
-		lapic_timer_oneshot_nointr(la, APIC_TIMER_MAX_COUNT);
-		DELAY(1000000);
-		value = APIC_TIMER_MAX_COUNT - lapic_read32(LAPIC_CCR_TIMER);
-		if (value != APIC_TIMER_MAX_COUNT)
+		if (freq * 2 / lapic_timer_divisor < APIC_TIMER_MAX_COUNT)
 			break;
 		lapic_timer_divisor <<= 1;
 	} while (lapic_timer_divisor <= 128);
 	if (lapic_timer_divisor > 128)
 		panic("lapic: Divisor too big");
+	count_freq = freq * 2 / lapic_timer_divisor;
 	if (bootverbose) {
 		printf("lapic: Divisor %lu, Frequency %lu Hz\n",
-		    lapic_timer_divisor, value);
+		    lapic_timer_divisor, count_freq);
 	}
-	count_freq = value;
 }
 
 static void
diff --git a/sys/x86/x86/tsc.c b/sys/x86/x86/tsc.c
index 3b2e044573f1..fa21d9c51fcb 100644
--- a/sys/x86/x86/tsc.c
+++ b/sys/x86/x86/tsc.c
@@ -48,6 +48,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/vdso.h>
 #include <machine/clock.h>
 #include <machine/cputypes.h>
+#include <machine/fpu.h>
 #include <machine/md_var.h>
 #include <machine/specialreg.h>
 #include <x86/vmware.h>
@@ -703,53 +704,18 @@ tsc_update_freq(uint64_t new_freq)
 void
 tsc_calibrate(void)
 {
-	struct timecounter *tc;
-	uint64_t freq, tsc_start, tsc_end;
-	u_int t_start, t_end;
-	register_t flags;
-	int cpu;
+	uint64_t freq;
 
 	if (tsc_disabled)
 		return;
 	if (tsc_early_calib_exact)
 		goto calibrated;
 
-	/*
-	 * Avoid using a low-quality timecounter to re-calibrate.  In
-	 * particular, old 32-bit platforms might only have the 8254 timer to
-	 * calibrate against.
-	 */
-	tc = atomic_load_ptr(&timecounter);
-	if (tc->tc_quality <= 0)
-		goto calibrated;
-
-	flags = intr_disable();
-	cpu = curcpu;
-	tsc_start = rdtsc_ordered();
-	t_start = tc->tc_get_timecount(tc) & tc->tc_counter_mask;
-	intr_restore(flags);
-
-	DELAY(1000000);
-
-	thread_lock(curthread);
-	sched_bind(curthread, cpu);
-
-	flags = intr_disable();
-	tsc_end = rdtsc_ordered();
-	t_end = tc->tc_get_timecount(tc) & tc->tc_counter_mask;
-	intr_restore(flags);
-
-	sched_unbind(curthread);
-	thread_unlock(curthread);
-
-	if (t_end <= t_start) {
-		/* Assume that the counter has wrapped around at most once. */
-		t_end += (uint64_t)tc->tc_counter_mask + 1;
-	}
-
-	freq = tc->tc_frequency * (tsc_end - tsc_start) / (t_end - t_start);
-
+	fpu_kern_enter(curthread, NULL, FPU_KERN_NOCTX);
+	freq = clockcalib(rdtsc_ordered, "TSC");
+	fpu_kern_leave(curthread, NULL);
 	tsc_update_freq(freq);
+
 calibrated:
 	tc_init(&tsc_timecounter);
 	set_cputicker(rdtsc, tsc_freq, !tsc_is_invariant);