[PATCH V4 4/7] cpufreq: Add a notification message that the highest perf has changed

From: Meng Li <li.meng@amd.com>
To: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Huang Rui <ray.huang@amd.com>
Cc: <linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<x86@kernel.org>, <linux-acpi@vger.kernel.org>,
	Shuah Khan <skhan@linuxfoundation.org>,
	<linux-kselftest@vger.kernel.org>,
	"Nathan Fontenot" <nathan.fontenot@amd.com>,
	Deepak Sharma <deepak.sharma@amd.com>,
	Alex Deucher <alexander.deucher@amd.com>,
	Mario Limonciello <mario.limonciello@amd.com>,
	Shimmer Huang <shimmer.huang@amd.com>,
	"Perry Yuan" <Perry.Yuan@amd.com>,
	Xiaojian Du <Xiaojian.Du@amd.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Borislav Petkov <bp@alien8.de>, Meng Li <li.meng@amd.com>
Subject: [PATCH V4 4/7] cpufreq: Add a notification message that the highest perf has changed
Date: Tue, 29 Aug 2023 14:43:37 +0800	[thread overview]
Message-ID: <20230829064340.1136448-5-li.meng@amd.com> (raw)
In-Reply-To: <20230829064340.1136448-1-li.meng@amd.com>

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.

Signed-off-by: Meng Li <li.meng@amd.com>
Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?highlight=cppc#cpc-continuous-performance-control
---
 drivers/acpi/processor_driver.c |  6 ++++++
 drivers/cpufreq/cpufreq.c       | 13 +++++++++++++
 include/linux/cpufreq.h         |  4 ++++
 3 files changed, 23 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 50bbc969ffe5..842357abfae6 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2675,6 +2675,19 @@ 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 9bf94ae08158..58106b3d9183 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -232,6 +232,7 @@ 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);
@@ -377,6 +378,9 @@ 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

