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-rw-r--r--drivers/acpi/processor_driver.c350
1 files changed, 350 insertions, 0 deletions
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
new file mode 100644
index 000000000..9d6aff226
--- /dev/null
+++ b/drivers/acpi/processor_driver.c
@@ -0,0 +1,350 @@
+/*
+ * processor_driver.c - ACPI Processor Driver
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
+ * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * - Added processor hotplug support
+ * Copyright (C) 2013, Intel Corporation
+ * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/cpu.h>
+#include <linux/cpuidle.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+
+#include <acpi/processor.h>
+
+#include "internal.h"
+
+#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
+#define ACPI_PROCESSOR_NOTIFY_POWER 0x81
+#define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82
+
+#define _COMPONENT ACPI_PROCESSOR_COMPONENT
+ACPI_MODULE_NAME("processor_driver");
+
+MODULE_AUTHOR("Paul Diefenbaugh");
+MODULE_DESCRIPTION("ACPI Processor Driver");
+MODULE_LICENSE("GPL");
+
+static int acpi_processor_start(struct device *dev);
+static int acpi_processor_stop(struct device *dev);
+
+static const struct acpi_device_id processor_device_ids[] = {
+ {ACPI_PROCESSOR_OBJECT_HID, 0},
+ {ACPI_PROCESSOR_DEVICE_HID, 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, processor_device_ids);
+
+static struct device_driver acpi_processor_driver = {
+ .name = "processor",
+ .bus = &cpu_subsys,
+ .acpi_match_table = processor_device_ids,
+ .probe = acpi_processor_start,
+ .remove = acpi_processor_stop,
+};
+
+static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
+{
+ struct acpi_device *device = data;
+ struct acpi_processor *pr;
+ int saved;
+
+ if (device->handle != handle)
+ return;
+
+ pr = acpi_driver_data(device);
+ if (!pr)
+ return;
+
+ switch (event) {
+ case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
+ saved = pr->performance_platform_limit;
+ acpi_processor_ppc_has_changed(pr, 1);
+ if (saved == pr->performance_platform_limit)
+ break;
+ acpi_bus_generate_netlink_event(device->pnp.device_class,
+ dev_name(&device->dev), event,
+ pr->performance_platform_limit);
+ break;
+ case ACPI_PROCESSOR_NOTIFY_POWER:
+ acpi_processor_power_state_has_changed(pr);
+ acpi_bus_generate_netlink_event(device->pnp.device_class,
+ dev_name(&device->dev), event, 0);
+ break;
+ case ACPI_PROCESSOR_NOTIFY_THROTTLING:
+ acpi_processor_tstate_has_changed(pr);
+ acpi_bus_generate_netlink_event(device->pnp.device_class,
+ dev_name(&device->dev), event, 0);
+ break;
+ default:
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Unsupported event [0x%x]\n", event));
+ break;
+ }
+
+ return;
+}
+
+static int __acpi_processor_start(struct acpi_device *device);
+
+static int acpi_soft_cpu_online(unsigned int cpu)
+{
+ struct acpi_processor *pr = per_cpu(processors, cpu);
+ struct acpi_device *device;
+
+ if (!pr || acpi_bus_get_device(pr->handle, &device))
+ return 0;
+ /*
+ * CPU got physically hotplugged and onlined for the first time:
+ * Initialize missing things.
+ */
+ if (pr->flags.need_hotplug_init) {
+ int ret;
+
+ pr_info("Will online and init hotplugged CPU: %d\n",
+ pr->id);
+ pr->flags.need_hotplug_init = 0;
+ ret = __acpi_processor_start(device);
+ WARN(ret, "Failed to start CPU: %d\n", pr->id);
+ } else {
+ /* Normal CPU soft online event. */
+ acpi_processor_ppc_has_changed(pr, 0);
+ acpi_processor_hotplug(pr);
+ acpi_processor_reevaluate_tstate(pr, false);
+ acpi_processor_tstate_has_changed(pr);
+ }
+ return 0;
+}
+
+static int acpi_soft_cpu_dead(unsigned int cpu)
+{
+ struct acpi_processor *pr = per_cpu(processors, cpu);
+ struct acpi_device *device;
+
+ if (!pr || acpi_bus_get_device(pr->handle, &device))
+ return 0;
+
+ acpi_processor_reevaluate_tstate(pr, true);
+ return 0;
+}
+
+#ifdef CONFIG_ACPI_CPU_FREQ_PSS
+static int acpi_pss_perf_init(struct acpi_processor *pr,
+ struct acpi_device *device)
+{
+ 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) {}
+#endif /* CONFIG_ACPI_CPU_FREQ_PSS */
+
+static int __acpi_processor_start(struct acpi_device *device)
+{
+ struct acpi_processor *pr = acpi_driver_data(device);
+ acpi_status status;
+ int result = 0;
+
+ if (!pr)
+ return -ENODEV;
+
+ if (pr->flags.need_hotplug_init)
+ return 0;
+
+ result = acpi_cppc_processor_probe(pr);
+ if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))
+ dev_dbg(&device->dev, "CPPC data invalid or not present\n");
+
+ if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
+ acpi_processor_power_init(pr);
+
+ result = acpi_pss_perf_init(pr, device);
+ if (result)
+ goto err_power_exit;
+
+ status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+ acpi_processor_notify, device);
+ if (ACPI_SUCCESS(status))
+ return 0;
+
+ result = -ENODEV;
+ acpi_pss_perf_exit(pr, device);
+
+err_power_exit:
+ acpi_processor_power_exit(pr);
+ return result;
+}
+
+static int acpi_processor_start(struct device *dev)
+{
+ struct acpi_device *device = ACPI_COMPANION(dev);
+ int ret;
+
+ if (!device)
+ return -ENODEV;
+
+ /* Protect against concurrent CPU hotplug operations */
+ cpu_hotplug_disable();
+ ret = __acpi_processor_start(device);
+ cpu_hotplug_enable();
+ return ret;
+}
+
+static int acpi_processor_stop(struct device *dev)
+{
+ struct acpi_device *device = ACPI_COMPANION(dev);
+ struct acpi_processor *pr;
+
+ if (!device)
+ return 0;
+
+ acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+ acpi_processor_notify);
+
+ pr = acpi_driver_data(device);
+ if (!pr)
+ return 0;
+ acpi_processor_power_exit(pr);
+
+ acpi_pss_perf_exit(pr, device);
+
+ acpi_cppc_processor_exit(pr);
+
+ return 0;
+}
+
+/*
+ * We keep the driver loaded even when ACPI is not running.
+ * This is needed for the powernow-k8 driver, that works even without
+ * ACPI, but needs symbols from this driver
+ */
+static enum cpuhp_state hp_online;
+static int __init acpi_processor_driver_init(void)
+{
+ int result = 0;
+
+ if (acpi_disabled)
+ return 0;
+
+ result = driver_register(&acpi_processor_driver);
+ if (result < 0)
+ return result;
+
+ result = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+ "acpi/cpu-drv:online",
+ acpi_soft_cpu_online, NULL);
+ if (result < 0)
+ goto err;
+ hp_online = result;
+ cpuhp_setup_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD, "acpi/cpu-drv:dead",
+ NULL, acpi_soft_cpu_dead);
+
+ acpi_thermal_cpufreq_init();
+ acpi_processor_ppc_init();
+ acpi_processor_throttling_init();
+ return 0;
+err:
+ driver_unregister(&acpi_processor_driver);
+ return result;
+}
+
+static void __exit acpi_processor_driver_exit(void)
+{
+ if (acpi_disabled)
+ return;
+
+ acpi_processor_ppc_exit();
+ acpi_thermal_cpufreq_exit();
+ cpuhp_remove_state_nocalls(hp_online);
+ cpuhp_remove_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD);
+ driver_unregister(&acpi_processor_driver);
+}
+
+module_init(acpi_processor_driver_init);
+module_exit(acpi_processor_driver_exit);
+
+MODULE_ALIAS("processor");