ACPI: processor: Split out thermal initialization from ACPI PSS

Commit 239708a3af44 ("ACPI: Split out ACPI PSS from ACPI Processor
driver"), moves processor thermal registration to acpi_pss_perf_init(),
which doesn't get executed if ACPI_CPU_FREQ_PSS is not enabled.

As ARM64 supports P-states using CPPC, it should be possible to also
support processor passive cooling even if PSS is not enabled. Split
out the processor thermal cooling register from ACPI PSS to support
this, and move it into a separate function in processor_thermal.c.

Signed-off-by: Riwen Lu <luriwen@kylinos.cn>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

4 files changed, 65 insertions, 68 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 1e34f846508f..2457ade3f82d 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -255,7 +255,6 @@ config ACPI_DOCK
 
 config ACPI_CPU_FREQ_PSS
 	bool
-	select THERMAL
 
 config ACPI_PROCESSOR_CSTATE
 	def_bool y
@@ -287,6 +286,7 @@ config ACPI_PROCESSOR
 	depends on X86 || IA64 || ARM64 || LOONGARCH
 	select ACPI_PROCESSOR_IDLE
 	select ACPI_CPU_FREQ_PSS if X86 || IA64 || LOONGARCH
+	select THERMAL
 	default y
 	help
 	  This driver adds support for the ACPI Processor package. It is required
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index b5a8d3e00a52..0002eecbf870 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -109,10 +109,9 @@ obj-$(CONFIG_ACPI_PPTT) 	+= pptt.o
 obj-$(CONFIG_ACPI_PFRUT)	+= pfr_update.o pfr_telemetry.o
 
 # processor has its own "processor." module_param namespace
-processor-y			:= processor_driver.o
+processor-y			:= processor_driver.o processor_thermal.o
 processor-$(CONFIG_ACPI_PROCESSOR_IDLE) += processor_idle.o
-processor-$(CONFIG_ACPI_CPU_FREQ_PSS)	+= processor_throttling.o	\
-	processor_thermal.o
+processor-$(CONFIG_ACPI_CPU_FREQ_PSS)	+= processor_throttling.o
 processor-$(CONFIG_CPU_FREQ)	+= processor_perflib.o
 
 obj-$(CONFIG_ACPI_PROCESSOR_AGGREGATOR) += acpi_pad.o
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 368a9edefd0c..1278969eec1f 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -139,75 +139,17 @@ static int acpi_soft_cpu_dead(unsigned int cpu)
 }
 
 #ifdef CONFIG_ACPI_CPU_FREQ_PSS
-static int acpi_pss_perf_init(struct acpi_processor *pr,
-		struct acpi_device *device)
+static void acpi_pss_perf_init(struct acpi_processor *pr)
 {
-	int result = 0;
-
 	acpi_processor_ppc_has_changed(pr, 0);
 
 	acpi_processor_get_throttling_info(pr);
 
 	if (pr->flags.throttling)
 		pr->flags.limit = 1;
-
-	pr->cdev = thermal_cooling_device_register("Processor", device,
-						   &processor_cooling_ops);
-	if (IS_ERR(pr->cdev)) {
-		result = PTR_ERR(pr->cdev);
-		return result;
-	}
-
-	dev_dbg(&device->dev, "registered as cooling_device%d\n",
-		pr->cdev->id);
-
-	result = sysfs_create_link(&device->dev.kobj,
-				   &pr->cdev->device.kobj,
-				   "thermal_cooling");
-	if (result) {
-		dev_err(&device->dev,
-			"Failed to create sysfs link 'thermal_cooling'\n");
-		goto err_thermal_unregister;
-	}
-
-	result = sysfs_create_link(&pr->cdev->device.kobj,
-				   &device->dev.kobj,
-				   "device");
-	if (result) {
-		dev_err(&pr->cdev->device,
-			"Failed to create sysfs link 'device'\n");
-		goto err_remove_sysfs_thermal;
-	}
-
-	return 0;
-
- err_remove_sysfs_thermal:
-	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
- err_thermal_unregister:
-	thermal_cooling_device_unregister(pr->cdev);
-
-	return result;
-}
-
-static void acpi_pss_perf_exit(struct acpi_processor *pr,
-		struct acpi_device *device)
-{
-	if (pr->cdev) {
-		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
-		sysfs_remove_link(&pr->cdev->device.kobj, "device");
-		thermal_cooling_device_unregister(pr->cdev);
-		pr->cdev = NULL;
-	}
 }
 #else
-static inline int acpi_pss_perf_init(struct acpi_processor *pr,
-		struct acpi_device *device)
-{
-	return 0;
-}
-
-static inline void acpi_pss_perf_exit(struct acpi_processor *pr,
-		struct acpi_device *device) {}
+static inline void acpi_pss_perf_init(struct acpi_processor *pr) {}
 #endif /* CONFIG_ACPI_CPU_FREQ_PSS */
 
 static int __acpi_processor_start(struct acpi_device *device)
@@ -229,7 +171,9 @@ static int __acpi_processor_start(struct acpi_device *device)
 	if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
 		acpi_processor_power_init(pr);
 
-	result = acpi_pss_perf_init(pr, device);
+	acpi_pss_perf_init(pr);
+
+	result = acpi_processor_thermal_init(pr, device);
 	if (result)
 		goto err_power_exit;
 
@@ -239,7 +183,7 @@ static int __acpi_processor_start(struct acpi_device *device)
 		return 0;
 
 	result = -ENODEV;
-	acpi_pss_perf_exit(pr, device);
+	acpi_processor_thermal_exit(pr, device);
 
 err_power_exit:
 	acpi_processor_power_exit(pr);
@@ -277,10 +221,10 @@ static int acpi_processor_stop(struct device *dev)
 		return 0;
 	acpi_processor_power_exit(pr);
 
-	acpi_pss_perf_exit(pr, device);
-
 	acpi_cppc_processor_exit(pr);
 
+	acpi_processor_thermal_exit(pr, device);
+
 	return 0;
 }
 
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index d8b2dfcd59b5..db6ac540e924 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c
@@ -266,3 +266,57 @@ const struct thermal_cooling_device_ops processor_cooling_ops = {
 	.get_cur_state = processor_get_cur_state,
 	.set_cur_state = processor_set_cur_state,
 };
+
+int acpi_processor_thermal_init(struct acpi_processor *pr,
+				struct acpi_device *device)
+{
+	int result = 0;
+
+	pr->cdev = thermal_cooling_device_register("Processor", device,
+						   &processor_cooling_ops);
+	if (IS_ERR(pr->cdev)) {
+		result = PTR_ERR(pr->cdev);
+		return result;
+	}
+
+	dev_dbg(&device->dev, "registered as cooling_device%d\n",
+		pr->cdev->id);
+
+	result = sysfs_create_link(&device->dev.kobj,
+				   &pr->cdev->device.kobj,
+				   "thermal_cooling");
+	if (result) {
+		dev_err(&device->dev,
+			"Failed to create sysfs link 'thermal_cooling'\n");
+		goto err_thermal_unregister;
+	}
+
+	result = sysfs_create_link(&pr->cdev->device.kobj,
+				   &device->dev.kobj,
+				   "device");
+	if (result) {
+		dev_err(&pr->cdev->device,
+			"Failed to create sysfs link 'device'\n");
+		goto err_remove_sysfs_thermal;
+	}
+
+	return 0;
+
+err_remove_sysfs_thermal:
+	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
+err_thermal_unregister:
+	thermal_cooling_device_unregister(pr->cdev);
+
+	return result;
+}
+
+void acpi_processor_thermal_exit(struct acpi_processor *pr,
+				 struct acpi_device *device)
+{
+	if (pr->cdev) {
+		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
+		sysfs_remove_link(&pr->cdev->device.kobj, "device");
+		thermal_cooling_device_unregister(pr->cdev);
+		pr->cdev = NULL;
+	}
+}