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-rw-r--r--arch/x86/Kconfig6
-rw-r--r--drivers/acpi/processor_idle.c47
-rw-r--r--drivers/cpuidle/Kconfig4
-rw-r--r--drivers/cpuidle/cpuidle.c43
-rw-r--r--include/acpi/processor.h3
-rw-r--r--include/linux/cpuidle.h26
6 files changed, 111 insertions, 18 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e6728bd..3954ae9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -98,6 +98,9 @@ config ARCH_HAS_ILOG2_U32
config ARCH_HAS_ILOG2_U64
def_bool n
+config ARCH_HAS_CPU_IDLE_WAIT
+ def_bool y
+
config GENERIC_CALIBRATE_DELAY
def_bool y
@@ -105,6 +108,9 @@ config GENERIC_TIME_VSYSCALL
bool
default X86_64
+config ARCH_HAS_CPU_RELAX
+ def_bool y
+
config HAVE_SETUP_PER_CPU_AREA
def_bool X86_64
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 199ea21..32003fd 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -98,6 +98,9 @@ module_param(bm_history, uint, 0644);
static int acpi_processor_set_power_policy(struct acpi_processor *pr);
+#else /* CONFIG_CPU_IDLE */
+static unsigned int latency_factor __read_mostly = 2;
+module_param(latency_factor, uint, 0644);
#endif
/*
@@ -201,6 +204,10 @@ static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2)
return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2);
}
+/*
+ * Callers should disable interrupts before the call and enable
+ * interrupts after return.
+ */
static void acpi_safe_halt(void)
{
current_thread_info()->status &= ~TS_POLLING;
@@ -261,7 +268,7 @@ static atomic_t c3_cpu_count;
/* Common C-state entry for C2, C3, .. */
static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
{
- if (cstate->space_id == ACPI_CSTATE_FFH) {
+ if (cstate->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cstate);
} else {
@@ -413,6 +420,8 @@ static void acpi_processor_idle(void)
pm_idle_save();
else
acpi_safe_halt();
+
+ local_irq_enable();
return;
}
@@ -521,6 +530,7 @@ static void acpi_processor_idle(void)
* skew otherwise.
*/
sleep_ticks = 0xFFFFFFFF;
+ local_irq_enable();
break;
case ACPI_STATE_C2:
@@ -922,20 +932,20 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
cx.address = reg->address;
cx.index = current_count + 1;
- cx.space_id = ACPI_CSTATE_SYSTEMIO;
+ cx.entry_method = ACPI_CSTATE_SYSTEMIO;
if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
if (acpi_processor_ffh_cstate_probe
(pr->id, &cx, reg) == 0) {
- cx.space_id = ACPI_CSTATE_FFH;
- } else if (cx.type != ACPI_STATE_C1) {
+ cx.entry_method = ACPI_CSTATE_FFH;
+ } else if (cx.type == ACPI_STATE_C1) {
/*
* C1 is a special case where FIXED_HARDWARE
* can be handled in non-MWAIT way as well.
* In that case, save this _CST entry info.
- * That is, we retain space_id of SYSTEM_IO for
- * halt based C1.
* Otherwise, ignore this info and continue.
*/
+ cx.entry_method = ACPI_CSTATE_HALT;
+ } else {
continue;
}
}
@@ -1369,12 +1379,16 @@ static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr,
/**
* acpi_idle_do_entry - a helper function that does C2 and C3 type entry
* @cx: cstate data
+ *
+ * Caller disables interrupt before call and enables interrupt after return.
*/
static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
{
- if (cx->space_id == ACPI_CSTATE_FFH) {
+ if (cx->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cx);
+ } else if (cx->entry_method == ACPI_CSTATE_HALT) {
+ acpi_safe_halt();
} else {
int unused;
/* IO port based C-state */
@@ -1396,21 +1410,27 @@ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
static int acpi_idle_enter_c1(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
+ u32 t1, t2;
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+
pr = processors[smp_processor_id()];
if (unlikely(!pr))
return 0;
+ local_irq_disable();
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);
- acpi_safe_halt();
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ acpi_idle_do_entry(cx);
+ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ local_irq_enable();
cx->usage++;
- return 0;
+ return ticks_elapsed_in_us(t1, t2);
}
/**
@@ -1517,7 +1537,9 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
if (dev->safe_state) {
return dev->safe_state->enter(dev, dev->safe_state);
} else {
+ local_irq_disable();
acpi_safe_halt();
+ local_irq_enable();
return 0;
}
}
@@ -1609,7 +1631,7 @@ struct cpuidle_driver acpi_idle_driver = {
*/
static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
{
- int i, count = 0;
+ int i, count = CPUIDLE_DRIVER_STATE_START;
struct acpi_processor_cx *cx;
struct cpuidle_state *state;
struct cpuidle_device *dev = &pr->power.dev;
@@ -1638,13 +1660,14 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
state->exit_latency = cx->latency;
- state->target_residency = cx->latency * 6;
+ state->target_residency = cx->latency * latency_factor;
state->power_usage = cx->power;
state->flags = 0;
switch (cx->type) {
case ACPI_STATE_C1:
state->flags |= CPUIDLE_FLAG_SHALLOW;
+ state->flags |= CPUIDLE_FLAG_TIME_VALID;
state->enter = acpi_idle_enter_c1;
dev->safe_state = state;
break;
@@ -1667,6 +1690,8 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
}
count++;
+ if (count == CPUIDLE_STATE_MAX)
+ break;
}
dev->state_count = count;
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 3bed412..7dbc4a8 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -1,13 +1,13 @@
config CPU_IDLE
bool "CPU idle PM support"
+ default ACPI
help
CPU idle is a generic framework for supporting software-controlled
idle processor power management. It includes modular cross-platform
governors that can be swapped during runtime.
- If you're using a mobile platform that supports CPU idle PM (e.g.
- an ACPI-capable notebook), you should say Y here.
+ If you're using an ACPI-enabled platform, you should say Y here.
config CPU_IDLE_GOV_LADDER
bool
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 2a98d99..d868d73 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -15,6 +15,7 @@
#include <linux/pm_qos_params.h>
#include <linux/cpu.h>
#include <linux/cpuidle.h>
+#include <linux/ktime.h>
#include "cpuidle.h"
@@ -82,7 +83,7 @@ void cpuidle_uninstall_idle_handler(void)
{
if (enabled_devices && (pm_idle != pm_idle_old)) {
pm_idle = pm_idle_old;
- cpu_idle_wait();
+ cpuidle_kick_cpus();
}
}
@@ -180,6 +181,44 @@ void cpuidle_disable_device(struct cpuidle_device *dev)
EXPORT_SYMBOL_GPL(cpuidle_disable_device);
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st)
+{
+ ktime_t t1, t2;
+ s64 diff;
+ int ret;
+
+ t1 = ktime_get();
+ local_irq_enable();
+ while (!need_resched())
+ cpu_relax();
+
+ t2 = ktime_get();
+ diff = ktime_to_us(ktime_sub(t2, t1));
+ if (diff > INT_MAX)
+ diff = INT_MAX;
+
+ ret = (int) diff;
+ return ret;
+}
+
+static void poll_idle_init(struct cpuidle_device *dev)
+{
+ struct cpuidle_state *state = &dev->states[0];
+
+ cpuidle_set_statedata(state, NULL);
+
+ snprintf(state->name, CPUIDLE_NAME_LEN, "C0 (poll idle)");
+ state->exit_latency = 0;
+ state->target_residency = 0;
+ state->power_usage = -1;
+ state->flags = CPUIDLE_FLAG_POLL | CPUIDLE_FLAG_TIME_VALID;
+ state->enter = poll_idle;
+}
+#else
+static void poll_idle_init(struct cpuidle_device *dev) {}
+#endif /* CONFIG_ARCH_HAS_CPU_RELAX */
+
/**
* cpuidle_register_device - registers a CPU's idle PM feature
* @dev: the cpu
@@ -198,6 +237,8 @@ int cpuidle_register_device(struct cpuidle_device *dev)
mutex_lock(&cpuidle_lock);
+ poll_idle_init(dev);
+
per_cpu(cpuidle_devices, dev->cpu) = dev;
list_add(&dev->device_list, &cpuidle_detected_devices);
if ((ret = cpuidle_add_sysfs(sys_dev))) {
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 6e253b5..f6d7c50 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -34,6 +34,7 @@
#define ACPI_CSTATE_SYSTEMIO (0)
#define ACPI_CSTATE_FFH (1)
+#define ACPI_CSTATE_HALT (2)
/* Power Management */
@@ -64,7 +65,7 @@ struct acpi_processor_cx {
u8 valid;
u8 type;
u32 address;
- u8 space_id;
+ u8 entry_method;
u8 index;
u32 latency;
u32 latency_ticks;
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index b0fd85a..c8eb8c7 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -46,9 +46,10 @@ struct cpuidle_state {
/* Idle State Flags */
#define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
#define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */
-#define CPUIDLE_FLAG_SHALLOW (0x10) /* low latency, minimal savings */
-#define CPUIDLE_FLAG_BALANCED (0x20) /* medium latency, moderate savings */
-#define CPUIDLE_FLAG_DEEP (0x40) /* high latency, large savings */
+#define CPUIDLE_FLAG_POLL (0x10) /* no latency, no savings */
+#define CPUIDLE_FLAG_SHALLOW (0x20) /* low latency, minimal savings */
+#define CPUIDLE_FLAG_BALANCED (0x40) /* medium latency, moderate savings */
+#define CPUIDLE_FLAG_DEEP (0x80) /* high latency, large savings */
#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
@@ -72,6 +73,19 @@ cpuidle_set_statedata(struct cpuidle_state *state, void *data)
state->driver_data = data;
}
+#ifdef CONFIG_SMP
+#ifdef CONFIG_ARCH_HAS_CPU_IDLE_WAIT
+static inline void cpuidle_kick_cpus(void)
+{
+ cpu_idle_wait();
+}
+#else /* !CONFIG_ARCH_HAS_CPU_IDLE_WAIT */
+#error "Arch needs cpu_idle_wait() equivalent here"
+#endif /* !CONFIG_ARCH_HAS_CPU_IDLE_WAIT */
+#else /* !CONFIG_SMP */
+static inline void cpuidle_kick_cpus(void) {}
+#endif /* !CONFIG_SMP */
+
struct cpuidle_state_kobj {
struct cpuidle_state *state;
struct completion kobj_unregister;
@@ -178,4 +192,10 @@ static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
#endif
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+#define CPUIDLE_DRIVER_STATE_START 1
+#else
+#define CPUIDLE_DRIVER_STATE_START 0
+#endif
+
#endif /* _LINUX_CPUIDLE_H */
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