[PATCH V12 4/7] cpufreq: Add a notification message that the highest perf has changed

Meng Li
2023-12-05T06:38:40Z

ACPI 6.5 section 8.4.6.1.1.1 specifies that Notify event 0x85 can be
emmitted to cause the the OSPM to re-evaluate the highest performance
register. Add support for this event.

Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Meng Li <li.meng@amd.com>
Link: https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#processor-device-notification-values
---
drivers/acpi/processor_driver.c | 6 ++++++
drivers/cpufreq/cpufreq.c | 13 +++++++++++++
include/linux/cpufreq.h | 5 +++++
3 files changed, 24 insertions(+)

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 4bd16b3f0781..29b2fb68a35d 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -27,6 +27,7 @@
#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
#define ACPI_PROCESSOR_NOTIFY_POWER 0x81
#define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82
+#define ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED 0x85

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI Processor Driver");
@@ -83,6 +84,11 @@ static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
acpi_bus_generate_netlink_event(device->pnp.device_class,
dev_name(&device->dev), event, 0);
break;
+ case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:
+ cpufreq_update_highest_perf(pr->id);
+ acpi_bus_generate_netlink_event(device->pnp.device_class,
+ dev_name(&device->dev), event, 0);
+ break;
default:
acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
break;
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 934d35f570b7..14a4cbc6dd05 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2717,6 +2717,19 @@ void cpufreq_update_limits(unsigned int cpu)
}
EXPORT_SYMBOL_GPL(cpufreq_update_limits);

+/**
+ * cpufreq_update_highest_perf - Update highest performance for a given CPU.
+ * @cpu: CPU to update the highest performance for.
+ *
+ * Invoke the driver's ->update_highest_perf callback if present
+ */
+void cpufreq_update_highest_perf(unsigned int cpu)
+{
+ if (cpufreq_driver->update_highest_perf)
+ cpufreq_driver->update_highest_perf(cpu);
+}
+EXPORT_SYMBOL_GPL(cpufreq_update_highest_perf);
+
/*********************************************************************
* BOOST *
*********************************************************************/
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 1c5ca92a0555..f62257b2a42f 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -235,6 +235,7 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
void refresh_frequency_limits(struct cpufreq_policy *policy);
void cpufreq_update_policy(unsigned int cpu);
void cpufreq_update_limits(unsigned int cpu);
+void cpufreq_update_highest_perf(unsigned int cpu);
bool have_governor_per_policy(void);
bool cpufreq_supports_freq_invariance(void);
struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
@@ -263,6 +264,7 @@ static inline bool cpufreq_supports_freq_invariance(void)
return false;
}
static inline void disable_cpufreq(void) { }
+static inline void cpufreq_update_highest_perf(unsigned int cpu) { }
#endif

#ifdef CONFIG_CPU_FREQ_STAT
@@ -380,6 +382,9 @@ struct cpufreq_driver {
/* Called to update policy limits on firmware notifications. */
void (*update_limits)(unsigned int cpu);

+ /* Called to update highest performance on firmware notifications. */
+ void (*update_highest_perf)(unsigned int cpu);
+
/* optional */
int (*bios_limit)(int cpu, unsigned int *limit);

--
2.34.1