diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/apic_64.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c index 395928de28e..09b82093bc7 100644 --- a/arch/x86/kernel/apic_64.c +++ b/arch/x86/kernel/apic_64.c @@ -964,8 +964,34 @@ void __init setup_boot_APIC_clock (void) setup_APIC_timer(); } +/* + * AMD C1E enabled CPUs have a real nasty problem: Some BIOSes set the + * C1E flag only in the secondary CPU, so when we detect the wreckage + * we already have enabled the boot CPU local apic timer. Check, if + * disable_apic_timer is set and the DUMMY flag is cleared. If yes, + * set the DUMMY flag again and force the broadcast mode in the + * clockevents layer. + */ +void __cpuinit check_boot_apic_timer_broadcast(void) +{ + struct clock_event_device *levt = &per_cpu(lapic_events, boot_cpu_id); + + if (!disable_apic_timer || + (lapic_clockevent.features & CLOCK_EVT_FEAT_DUMMY)) + return; + + printk(KERN_INFO "AMD C1E detected late. Force timer broadcast.\n"); + lapic_clockevent.features |= CLOCK_EVT_FEAT_DUMMY; + levt->features |= CLOCK_EVT_FEAT_DUMMY; + + local_irq_enable(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_FORCE, &boot_cpu_id); + local_irq_disable(); +} + void __cpuinit setup_secondary_APIC_clock(void) { + check_boot_apic_timer_broadcast(); setup_APIC_timer(); } |