diff options
| -rw-r--r-- | arch/i386/kernel/apic.c | 78 |
1 files changed, 27 insertions, 51 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c index 2383bcf18c5..5cff7970911 100644 --- a/arch/i386/kernel/apic.c +++ b/arch/i386/kernel/apic.c @@ -338,6 +338,7 @@ void __init setup_boot_APIC_clock(void) void (*real_handler)(struct clock_event_device *dev); unsigned long deltaj; long delta, deltapm; + int pm_referenced = 0; apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n" "calibrating APIC timer ...\n"); @@ -357,7 +358,8 @@ void __init setup_boot_APIC_clock(void) /* Let the interrupts run */ local_irq_enable(); - while(lapic_cal_loops <= LAPIC_CAL_LOOPS); + while (lapic_cal_loops <= LAPIC_CAL_LOOPS) + cpu_relax(); local_irq_disable(); @@ -394,6 +396,7 @@ void __init setup_boot_APIC_clock(void) "%lu (%ld)\n", (unsigned long) res, delta); delta = (long) res; } + pm_referenced = 1; } /* Calculate the scaled math multiplication factor */ @@ -423,68 +426,41 @@ void __init setup_boot_APIC_clock(void) calibration_result / (1000000 / HZ), calibration_result % (1000000 / HZ)); - - apic_printk(APIC_VERBOSE, "... verify APIC timer\n"); - - /* - * Setup the apic timer manually - */ local_apic_timer_verify_ok = 1; - levt->event_handler = lapic_cal_handler; - lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt); - lapic_cal_loops = -1; - /* Let the interrupts run */ - local_irq_enable(); + /* We trust the pm timer based calibration */ + if (!pm_referenced) { + apic_printk(APIC_VERBOSE, "... verify APIC timer\n"); - while(lapic_cal_loops <= LAPIC_CAL_LOOPS); + /* + * Setup the apic timer manually + */ + levt->event_handler = lapic_cal_handler; + lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt); + lapic_cal_loops = -1; - local_irq_disable(); + /* Let the interrupts run */ + local_irq_enable(); - /* Stop the lapic timer */ - lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt); + while(lapic_cal_loops <= LAPIC_CAL_LOOPS) + cpu_relax(); - local_irq_enable(); + local_irq_disable(); - /* Jiffies delta */ - deltaj = lapic_cal_j2 - lapic_cal_j1; - apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj); + /* Stop the lapic timer */ + lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt); - /* Check, if the PM timer is available */ - deltapm = lapic_cal_pm2 - lapic_cal_pm1; - apic_printk(APIC_VERBOSE, "... PM timer delta = %ld\n", deltapm); + local_irq_enable(); - local_apic_timer_verify_ok = 0; + /* Jiffies delta */ + deltaj = lapic_cal_j2 - lapic_cal_j1; + apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj); - if (deltapm) { - if (deltapm > (pm_100ms - pm_thresh) && - deltapm < (pm_100ms + pm_thresh)) { - apic_printk(APIC_VERBOSE, "... PM timer result ok\n"); - /* Check, if the jiffies result is consistent */ - if (deltaj < LAPIC_CAL_LOOPS-2 || - deltaj > LAPIC_CAL_LOOPS+2) { - /* - * Not sure, what we can do about this one. - * When high resultion timers are active - * and the lapic timer does not stop in C3 - * we are fine. Otherwise more trouble might - * be waiting. -- tglx - */ - printk(KERN_WARNING "Global event device %s " - "has wrong frequency " - "(%lu ticks instead of %d)\n", - global_clock_event->name, deltaj, - LAPIC_CAL_LOOPS); - } - local_apic_timer_verify_ok = 1; - } - } else { /* Check, if the jiffies result is consistent */ - if (deltaj >= LAPIC_CAL_LOOPS-2 && - deltaj <= LAPIC_CAL_LOOPS+2) { + if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2) apic_printk(APIC_VERBOSE, "... jiffies result ok\n"); - local_apic_timer_verify_ok = 1; - } + else + local_apic_timer_verify_ok = 0; } if (!local_apic_timer_verify_ok) { |