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: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Patryk Wlazlyn <patryk.wlazlyn@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/all/20250205155211.329780-3-artem.bityutskiy%40linux.intel.com

diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 5854f0b8f0f19410ae249af1cc980a10dd76c250..5bdb65516969d60c479eb686b731d471f94b61af 100644 (file)
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -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();

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 698897b29de2448e55e031a02436e6d92847bee9..586cc7d1d8aa332cf631f2b62efef70df0f87886 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -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;
        }

diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index a17e97e634a6819da38e0340943ec0e13cb044d9..63a37e72b7218cd368c44be01f6d961e707a0e2f 100644 (file)
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -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,