Commit 541ddf31 authored by Patryk Wlazlyn's avatar Patryk Wlazlyn Committed by Dave Hansen
Browse files

ACPI/processor_idle: Add FFH state handling 



Recent Intel platforms will depend on the idle driver to pass the
correct hint for playing dead via mwait_play_dead_with_hint(). Expand
the existing enter_dead interface with handling for FFH states and pass
the MWAIT hint to the mwait_play_dead code.

Suggested-by: default avatarGautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: default avatarPatryk Wlazlyn <patryk.wlazlyn@linux.intel.com>
Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/all/20250205155211.329780-3-artem.bityutskiy%40linux.intel.com
parent a7dd183f

arch/x86/kernel/acpi/cstate.c

+10 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <asm/cpuid.h>

#include <asm/mwait.h>

#include <asm/special_insns.h>

#include <asm/smp.h>



/*

 * Initialize bm_flags based on the CPU cache properties
@@ -205,6 +206,15 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu, 
}

EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe);



void acpi_processor_ffh_play_dead(struct acpi_processor_cx *cx)

{

	unsigned int cpu = smp_processor_id();

	struct cstate_entry *percpu_entry;



	percpu_entry = per_cpu_ptr(cpu_cstate_entry, cpu);

	mwait_play_dead(percpu_entry->states[cx->index].eax);

}



void __cpuidle acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx)

{

	unsigned int cpu = smp_processor_id();

drivers/acpi/processor_idle.c

+2 −0
Original line number Diff line number Diff line
@@ -590,6 +590,8 @@ static void acpi_idle_play_dead(struct cpuidle_device *dev, int index) 
			raw_safe_halt();

		else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {

			io_idle(cx->address);

		} else if (cx->entry_method == ACPI_CSTATE_FFH) {

			acpi_processor_ffh_play_dead(cx);

		} else

			return;

	}

include/acpi/processor.h

+5 −0
Original line number Diff line number Diff line
@@ -280,6 +280,7 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu, 
				    struct acpi_processor_cx *cx,

				    struct acpi_power_register *reg);

void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cstate);

void acpi_processor_ffh_play_dead(struct acpi_processor_cx *cx);

#else

static inline void acpi_processor_power_init_bm_check(struct

						      acpi_processor_flags
@@ -300,6 +301,10 @@ static inline void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx 
{

	return;

}

static inline void acpi_processor_ffh_play_dead(struct acpi_processor_cx *cx)

{

	return;

}

#endif



static inline int call_on_cpu(int cpu, long (*fn)(void *), void *arg,