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. Cc: x86@xxxxxxxxxx Cc: linux-ia64@xxxxxxxxxxxxxxx Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx> --- arch/ia64/Kconfig | 1 + arch/x86/Kconfig | 1 + drivers/acpi/Kconfig | 4 +++ drivers/acpi/processor_idle.c | 80 ++++++++++++++++++++++++++++--------------- include/acpi/processor.h | 2 +- 5 files changed, 60 insertions(+), 28 deletions(-) diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index b534ebab36ea..e820670d7243 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -15,6 +15,7 @@ config IA64 select ARCH_MIGHT_HAVE_PC_SERIO select PCI if (!IA64_HP_SIM) select ACPI if (!IA64_HP_SIM) + select ACPI_PROCESSOR_CSTATE if ACPI select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI select HAVE_UNSTABLE_SCHED_CLOCK diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2dc18605831f..cb3e14757c9c 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -18,6 +18,7 @@ config X86_64 config X86 def_bool y select ACPI_LEGACY_TABLES_LOOKUP if ACPI + select ACPI_PROCESSOR_CSTATE if ACPI select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI select ANON_INODES select ARCH_CLOCKSOURCE_DATA diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index b7e2e776397d..093bfcc4f9c3 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 + bool + 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, -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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