diff options
Diffstat (limited to 'drivers/acpi/processor_idle.c')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 122 |
1 files changed, 103 insertions, 19 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 92f5185464d..60773005b8a 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -39,6 +39,25 @@ #include <linux/moduleparam.h> #include <linux/sched.h> /* need_resched() */ #include <linux/latency.h> +#include <linux/clockchips.h> + +/* + * Include the apic definitions for x86 to have the APIC timer related defines + * available also for UP (on SMP it gets magically included via linux/smp.h). + * asm/acpi.h is not an option, as it would require more include magic. Also + * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. + */ +#ifdef CONFIG_X86 +#include <asm/apic.h> +#endif + +/* + * Include the apic definitions for x86 to have the APIC timer related defines + * available also for UP (on SMP it gets magically included via linux/smp.h). + */ +#ifdef CONFIG_X86 +#include <asm/apic.h> +#endif #include <asm/io.h> #include <asm/uaccess.h> @@ -237,6 +256,81 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate) } } +#ifdef ARCH_APICTIMER_STOPS_ON_C3 + +/* + * Some BIOS implementations switch to C3 in the published C2 state. + * This seems to be a common problem on AMD boxen, but other vendors + * are affected too. We pick the most conservative approach: we assume + * that the local APIC stops in both C2 and C3. + */ +static void acpi_timer_check_state(int state, struct acpi_processor *pr, + struct acpi_processor_cx *cx) +{ + struct acpi_processor_power *pwr = &pr->power; + + /* + * Check, if one of the previous states already marked the lapic + * unstable + */ + if (pwr->timer_broadcast_on_state < state) + return; + + if (cx->type >= ACPI_STATE_C2) + pr->power.timer_broadcast_on_state = state; +} + +static void acpi_propagate_timer_broadcast(struct acpi_processor *pr) +{ +#ifdef CONFIG_GENERIC_CLOCKEVENTS + unsigned long reason; + + reason = pr->power.timer_broadcast_on_state < INT_MAX ? + CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; + + clockevents_notify(reason, &pr->id); +#else + cpumask_t mask = cpumask_of_cpu(pr->id); + + if (pr->power.timer_broadcast_on_state < INT_MAX) + on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1); + else + on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1); +#endif +} + +/* Power(C) State timer broadcast control */ +static void acpi_state_timer_broadcast(struct acpi_processor *pr, + struct acpi_processor_cx *cx, + int broadcast) +{ +#ifdef CONFIG_GENERIC_CLOCKEVENTS + + int state = cx - pr->power.states; + + if (state >= pr->power.timer_broadcast_on_state) { + unsigned long reason; + + reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER : + CLOCK_EVT_NOTIFY_BROADCAST_EXIT; + clockevents_notify(reason, &pr->id); + } +#endif +} + +#else + +static void acpi_timer_check_state(int state, struct acpi_processor *pr, + struct acpi_processor_cx *cstate) { } +static void acpi_propagate_timer_broadcast(struct acpi_processor *pr) { } +static void acpi_state_timer_broadcast(struct acpi_processor *pr, + struct acpi_processor_cx *cx, + int broadcast) +{ +} + +#endif + static void acpi_processor_idle(void) { struct acpi_processor *pr = NULL; @@ -381,6 +475,7 @@ static void acpi_processor_idle(void) /* Get start time (ticks) */ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); /* Invoke C2 */ + acpi_state_timer_broadcast(pr, cx, 1); acpi_cstate_enter(cx); /* Get end time (ticks) */ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); @@ -395,6 +490,7 @@ static void acpi_processor_idle(void) /* Compute time (ticks) that we were actually asleep */ sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; + acpi_state_timer_broadcast(pr, cx, 0); break; case ACPI_STATE_C3: @@ -416,6 +512,7 @@ static void acpi_processor_idle(void) /* Get start time (ticks) */ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); /* Invoke C3 */ + acpi_state_timer_broadcast(pr, cx, 1); acpi_cstate_enter(cx); /* Get end time (ticks) */ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); @@ -435,6 +532,7 @@ static void acpi_processor_idle(void) /* Compute time (ticks) that we were actually asleep */ sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; + acpi_state_timer_broadcast(pr, cx, 0); break; default: @@ -903,11 +1001,7 @@ static int acpi_processor_power_verify(struct acpi_processor *pr) unsigned int i; unsigned int working = 0; -#ifdef ARCH_APICTIMER_STOPS_ON_C3 - int timer_broadcast = 0; - cpumask_t mask = cpumask_of_cpu(pr->id); - on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1); -#endif + pr->power.timer_broadcast_on_state = INT_MAX; for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { struct acpi_processor_cx *cx = &pr->power.states[i]; @@ -919,21 +1013,14 @@ static int acpi_processor_power_verify(struct acpi_processor *pr) case ACPI_STATE_C2: acpi_processor_power_verify_c2(cx); -#ifdef ARCH_APICTIMER_STOPS_ON_C3 - /* Some AMD systems fake C3 as C2, but still - have timer troubles */ - if (cx->valid && - boot_cpu_data.x86_vendor == X86_VENDOR_AMD) - timer_broadcast++; -#endif + if (cx->valid) + acpi_timer_check_state(i, pr, cx); break; case ACPI_STATE_C3: acpi_processor_power_verify_c3(pr, cx); -#ifdef ARCH_APICTIMER_STOPS_ON_C3 if (cx->valid) - timer_broadcast++; -#endif + acpi_timer_check_state(i, pr, cx); break; } @@ -941,10 +1028,7 @@ static int acpi_processor_power_verify(struct acpi_processor *pr) working++; } -#ifdef ARCH_APICTIMER_STOPS_ON_C3 - if (timer_broadcast) - on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1); -#endif + acpi_propagate_timer_broadcast(pr); return (working); } |