diff options
author | Sudeep Holla <Sudeep.Holla@arm.com> | 2016-07-19 18:52:53 +0100 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-07-21 23:24:35 +0200 |
commit | 35ae713355868aa493edbfbabf615473473215cc (patch) | |
tree | 3ee0ef3e3d20c76cfb774d9e39d11b55aca1e4cb | |
parent | 92d21ac74a9e3c09b0b01c764e530657e4c85c49 (diff) | |
download | lwn-35ae713355868aa493edbfbabf615473473215cc.tar.gz lwn-35ae713355868aa493edbfbabf615473473215cc.zip |
ACPI / processor_idle: introduce ACPI_PROCESSOR_CSTATE
ACPI 6.0 adds a new method to specify the CPU idle states(C-states)
called Low Power Idle(LPI) states. Since new architectures like ARM64
use only LPIs, introduce ACPI_PROCESSOR_CSTATE to encapsulate all the
code supporting the old style C-states(_CST).
This patch will help to extend the processor_idle module to support
LPI.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-rw-r--r-- | drivers/acpi/Kconfig | 4 | ||||
-rw-r--r-- | drivers/acpi/processor_idle.c | 80 | ||||
-rw-r--r-- | include/acpi/processor.h | 2 |
3 files changed, 58 insertions, 28 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index b7e2e776397d..1358fb7d7a68 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -213,6 +213,10 @@ config ACPI_CPU_FREQ_PSS bool select THERMAL +config ACPI_PROCESSOR_CSTATE + def_bool y + depends on IA64 || X86 + config ACPI_PROCESSOR_IDLE bool select CPU_IDLE diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 444e3745c8b3..ca0de35d1c3a 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -59,6 +59,12 @@ module_param(latency_factor, uint, 0644); static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device); +struct cpuidle_driver acpi_idle_driver = { + .name = "acpi_idle", + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE static DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX], acpi_cstate); @@ -804,11 +810,6 @@ static void acpi_idle_enter_freeze(struct cpuidle_device *dev, acpi_idle_do_entry(cx); } -struct cpuidle_driver acpi_idle_driver = { - .name = "acpi_idle", - .owner = THIS_MODULE, -}; - /** * acpi_processor_setup_cpuidle_cx - prepares and configures CPUIDLE * device i.e. per-cpu data @@ -925,6 +926,50 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) return 0; } +static inline void acpi_processor_cstate_first_run_checks(void) +{ + acpi_status status; + static int first_run; + + if (first_run) + return; + dmi_check_system(processor_power_dmi_table); + max_cstate = acpi_processor_cstate_check(max_cstate); + if (max_cstate < ACPI_C_STATES_MAX) + pr_notice("ACPI: processor limited to max C-state %d\n", + max_cstate); + first_run++; + + if (acpi_gbl_FADT.cst_control && !nocst) { + status = acpi_os_write_port(acpi_gbl_FADT.smi_command, + acpi_gbl_FADT.cst_control, 8); + if (ACPI_FAILURE(status)) + ACPI_EXCEPTION((AE_INFO, status, + "Notifying BIOS of _CST ability failed")); + } +} +#else + +static inline int disabled_by_idle_boot_param(void) { return 0; } +static inline void acpi_processor_cstate_first_run_checks(void) { } +static int acpi_processor_get_power_info(struct acpi_processor *pr) +{ + return -ENODEV; +} + +static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, + struct cpuidle_device *dev) +{ + return -EINVAL; +} + +static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) +{ + return -EINVAL; +} + +#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ + int acpi_processor_hotplug(struct acpi_processor *pr) { int ret = 0; @@ -1015,35 +1060,16 @@ static int acpi_processor_registered; int acpi_processor_power_init(struct acpi_processor *pr) { - acpi_status status; int retval; struct cpuidle_device *dev; - static int first_run; if (disabled_by_idle_boot_param()) return 0; - if (!first_run) { - dmi_check_system(processor_power_dmi_table); - max_cstate = acpi_processor_cstate_check(max_cstate); - if (max_cstate < ACPI_C_STATES_MAX) - printk(KERN_NOTICE - "ACPI: processor limited to max C-state %d\n", - max_cstate); - first_run++; - } + acpi_processor_cstate_first_run_checks(); - if (acpi_gbl_FADT.cst_control && !nocst) { - status = - acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8); - if (ACPI_FAILURE(status)) { - ACPI_EXCEPTION((AE_INFO, status, - "Notifying BIOS of _CST ability failed")); - } - } - - acpi_processor_get_power_info(pr); - pr->flags.power_setup_done = 1; + if (!acpi_processor_get_power_info(pr)) + pr->flags.power_setup_done = 1; /* * Install the idle handler if processor power management is supported. diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 6f1805dd5d3c..48779d678122 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -242,7 +242,7 @@ extern int acpi_processor_get_performance_info(struct acpi_processor *pr); DECLARE_PER_CPU(struct acpi_processor *, processors); extern struct acpi_processor_errata errata; -#ifdef ARCH_HAS_POWER_INIT +#if defined(ARCH_HAS_POWER_INIT) && defined(CONFIG_ACPI_PROCESSOR_CSTATE) void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags, unsigned int cpu); int acpi_processor_ffh_cstate_probe(unsigned int cpu, |