ACPI / processor_idle: Add support for Low Power Idle(LPI) states
ACPI 6.0 introduced an optional object _LPI that provides an alternate
method to describe Low Power Idle states. It defines the local power
states for each node in a hierarchical processor topology. The OSPM can
use _LPI object to select a local power state for each level of processor
hierarchy in the system. They used to produce a composite power state
request that is presented to the platform by the OSPM.
Since multiple processors affect the idle state for any non-leaf hierarchy
node, coordination of idle state requests between the processors is
required. ACPI supports two different coordination schemes: Platform
coordinated and OS initiated.
This patch adds initial support for Platform coordination scheme of LPI.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 48779d6..e2dcb0c 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -39,6 +39,7 @@
#define ACPI_CSTATE_SYSTEMIO 0
#define ACPI_CSTATE_FFH 1
#define ACPI_CSTATE_HALT 2
+#define ACPI_CSTATE_INTEGER 3
#define ACPI_CX_DESC_LEN 32
@@ -67,9 +68,25 @@
char desc[ACPI_CX_DESC_LEN];
};
+struct acpi_lpi_state {
+ u32 min_residency;
+ u32 wake_latency; /* worst case */
+ u32 flags;
+ u32 arch_flags;
+ u32 res_cnt_freq;
+ u32 enable_parent_state;
+ u64 address;
+ u8 index;
+ u8 entry_method;
+ char desc[ACPI_CX_DESC_LEN];
+};
+
struct acpi_processor_power {
int count;
- struct acpi_processor_cx states[ACPI_PROCESSOR_MAX_POWER];
+ union {
+ struct acpi_processor_cx states[ACPI_PROCESSOR_MAX_POWER];
+ struct acpi_lpi_state lpi_states[ACPI_PROCESSOR_MAX_POWER];
+ };
int timer_broadcast_on_state;
};
@@ -189,6 +206,7 @@
u8 bm_control:1;
u8 bm_check:1;
u8 has_cst:1;
+ u8 has_lpi:1;
u8 power_setup_done:1;
u8 bm_rld_set:1;
u8 need_hotplug_init:1;
@@ -371,7 +389,7 @@
#ifdef CONFIG_ACPI_PROCESSOR_IDLE
int acpi_processor_power_init(struct acpi_processor *pr);
int acpi_processor_power_exit(struct acpi_processor *pr);
-int acpi_processor_cst_has_changed(struct acpi_processor *pr);
+int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
int acpi_processor_hotplug(struct acpi_processor *pr);
#else
static inline int acpi_processor_power_init(struct acpi_processor *pr)
@@ -384,7 +402,7 @@
return -ENODEV;
}
-static inline int acpi_processor_cst_has_changed(struct acpi_processor *pr)
+static inline int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
{
return -ENODEV;
}