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Diffstat (limited to 'drivers/acpi/processor_idle.c')
-rw-r--r--drivers/acpi/processor_idle.c99
1 files changed, 69 insertions, 30 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 80ffc782991..1f6fb38de01 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -63,6 +63,7 @@
ACPI_MODULE_NAME("processor_idle");
#define ACPI_PROCESSOR_FILE_POWER "power"
#define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000)
+#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY)
#define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */
#define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */
static void (*pm_idle_save) (void) __read_mostly;
@@ -91,7 +92,7 @@ module_param(bm_history, uint, 0644);
*
* To skip this limit, boot/load with a large max_cstate limit.
*/
-static int set_max_cstate(struct dmi_system_id *id)
+static int set_max_cstate(const struct dmi_system_id *id)
{
if (max_cstate > ACPI_PROCESSOR_MAX_POWER)
return 0;
@@ -275,21 +276,12 @@ static void acpi_timer_check_state(int state, struct acpi_processor *pr,
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 */
@@ -297,8 +289,6 @@ 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) {
@@ -308,7 +298,6 @@ static void acpi_state_timer_broadcast(struct acpi_processor *pr,
CLOCK_EVT_NOTIFY_BROADCAST_EXIT;
clockevents_notify(reason, &pr->id);
}
-#endif
}
#else
@@ -324,6 +313,23 @@ static void acpi_state_timer_broadcast(struct acpi_processor *pr,
#endif
+/*
+ * Suspend / resume control
+ */
+static int acpi_idle_suspend;
+
+int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
+{
+ acpi_idle_suspend = 1;
+ return 0;
+}
+
+int acpi_processor_resume(struct acpi_device * device)
+{
+ acpi_idle_suspend = 0;
+ return 0;
+}
+
static void acpi_processor_idle(void)
{
struct acpi_processor *pr = NULL;
@@ -354,7 +360,7 @@ static void acpi_processor_idle(void)
}
cx = pr->power.state;
- if (!cx) {
+ if (!cx || acpi_idle_suspend) {
if (pm_idle_save)
pm_idle_save();
else
@@ -462,6 +468,9 @@ static void acpi_processor_idle(void)
* TBD: Can't get time duration while in C1, as resumes
* go to an ISR rather than here. Need to instrument
* base interrupt handler.
+ *
+ * Note: the TSC better not stop in C1, sched_clock() will
+ * skew otherwise.
*/
sleep_ticks = 0xFFFFFFFF;
break;
@@ -469,28 +478,45 @@ static void acpi_processor_idle(void)
case ACPI_STATE_C2:
/* Get start time (ticks) */
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ /* Tell the scheduler that we are going deep-idle: */
+ sched_clock_idle_sleep_event();
/* 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);
-#ifdef CONFIG_GENERIC_TIME
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
/* TSC halts in C2, so notify users */
mark_tsc_unstable("possible TSC halt in C2");
#endif
+ /* Compute time (ticks) that we were actually asleep */
+ sleep_ticks = ticks_elapsed(t1, t2);
+
+ /* Tell the scheduler how much we idled: */
+ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS);
+
/* Re-enable interrupts */
local_irq_enable();
+ /* Do not account our idle-switching overhead: */
+ sleep_ticks -= cx->latency_ticks + C2_OVERHEAD;
+
current_thread_info()->status |= TS_POLLING;
- /* 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:
-
- if (pr->flags.bm_check) {
+ /*
+ * disable bus master
+ * bm_check implies we need ARB_DIS
+ * !bm_check implies we need cache flush
+ * bm_control implies whether we can do ARB_DIS
+ *
+ * That leaves a case where bm_check is set and bm_control is
+ * not set. In that case we cannot do much, we enter C3
+ * without doing anything.
+ */
+ if (pr->flags.bm_check && pr->flags.bm_control) {
if (atomic_inc_return(&c3_cpu_count) ==
num_online_cpus()) {
/*
@@ -499,7 +525,7 @@ static void acpi_processor_idle(void)
*/
acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
}
- } else {
+ } else if (!pr->flags.bm_check) {
/* SMP with no shared cache... Invalidate cache */
ACPI_FLUSH_CPU_CACHE();
}
@@ -508,25 +534,32 @@ static void acpi_processor_idle(void)
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Invoke C3 */
acpi_state_timer_broadcast(pr, cx, 1);
+ /* Tell the scheduler that we are going deep-idle: */
+ sched_clock_idle_sleep_event();
acpi_cstate_enter(cx);
/* Get end time (ticks) */
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
- if (pr->flags.bm_check) {
+ if (pr->flags.bm_check && pr->flags.bm_control) {
/* Enable bus master arbitration */
atomic_dec(&c3_cpu_count);
acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
}
-#ifdef CONFIG_GENERIC_TIME
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
/* TSC halts in C3, so notify users */
mark_tsc_unstable("TSC halts in C3");
#endif
+ /* Compute time (ticks) that we were actually asleep */
+ sleep_ticks = ticks_elapsed(t1, t2);
+ /* Tell the scheduler how much we idled: */
+ sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS);
+
/* Re-enable interrupts */
local_irq_enable();
+ /* Do not account our idle-switching overhead: */
+ sleep_ticks -= cx->latency_ticks + C3_OVERHEAD;
+
current_thread_info()->status |= TS_POLLING;
- /* 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;
@@ -959,11 +992,17 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
}
if (pr->flags.bm_check) {
- /* bus mastering control is necessary */
if (!pr->flags.bm_control) {
- ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "C3 support requires bus mastering control\n"));
- return;
+ if (pr->flags.has_cst != 1) {
+ /* bus mastering control is necessary */
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "C3 support requires BM control\n"));
+ return;
+ } else {
+ /* Here we enter C3 without bus mastering */
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "C3 support without BM control\n"));
+ }
}
} else {
/*
generated by cgit (git 2.34.1) at 2025-09-12 10:08:48 +0000