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>
This commit is contained in:
Sudeep Holla
2016-07-21 17:18:07 +01:00
committed by Rafael J. Wysocki
parent 35ae713355
commit a36a7fecfe
5 changed files with 450 additions and 60 deletions

View File

@@ -444,8 +444,12 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context);
#define OSC_SB_HOTPLUG_OST_SUPPORT 0x00000008
#define OSC_SB_APEI_SUPPORT 0x00000010
#define OSC_SB_CPC_SUPPORT 0x00000020
#define OSC_SB_CPCV2_SUPPORT 0x00000040
#define OSC_SB_PCLPI_SUPPORT 0x00000080
#define OSC_SB_OSLPI_SUPPORT 0x00000100
extern bool osc_sb_apei_support_acked;
extern bool osc_pc_lpi_support_confirmed;
/* PCI Host Bridge _OSC: Capabilities DWORD 2: Support Field */
#define OSC_PCI_EXT_CONFIG_SUPPORT 0x00000001