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Release 4.9 drivers/thermal/x86_pkg_temp_thermal.c

Directory: drivers/thermal
/*
 * x86_pkg_temp_thermal driver
 * Copyright (c) 2013, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/param.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <linux/slab.h>
#include <linux/pm.h>
#include <linux/thermal.h>
#include <linux/debugfs.h>
#include <asm/cpu_device_id.h>
#include <asm/mce.h>

/*
* Rate control delay: Idea is to introduce denounce effect
* This should be long enough to avoid reduce events, when
* threshold is set to a temperature, which is constantly
* violated, but at the short enough to take any action.
* The action can be remove threshold or change it to next
* interesting setting. Based on experiments, in around
* every 5 seconds under load will give us a significant
* temperature change.
*/

#define PKG_TEMP_THERMAL_NOTIFY_DELAY	5000

static int notify_delay_ms = PKG_TEMP_THERMAL_NOTIFY_DELAY;
module_param(notify_delay_ms, int, 0644);
MODULE_PARM_DESC(notify_delay_ms,
	"User space notification delay in milli seconds.");

/* Number of trip points in thermal zone. Currently it can't
* be more than 2. MSR can allow setting and getting notifications
* for only 2 thresholds. This define enforces this, if there
* is some wrong values returned by cpuid for number of thresholds.
*/

#define MAX_NUMBER_OF_TRIPS	2
/* Limit number of package temp zones */

#define MAX_PKG_TEMP_ZONE_IDS	256


struct phy_dev_entry {
	
struct list_head list;
	
u16 phys_proc_id;
	
u16 first_cpu;
	
u32 tj_max;
	
int ref_cnt;
	
u32 start_pkg_therm_low;
	
u32 start_pkg_therm_high;
	
struct thermal_zone_device *tzone;
};


static struct thermal_zone_params pkg_temp_tz_params = {
	.no_hwmon	= true,
};

/* List maintaining number of package instances */
static LIST_HEAD(phy_dev_list);
static DEFINE_MUTEX(phy_dev_list_mutex);

/* Interrupt to work function schedule queue */
static DEFINE_PER_CPU(struct delayed_work, pkg_temp_thermal_threshold_work);

/* To track if the work is already scheduled on a package */

static u8 *pkg_work_scheduled;

/* Spin lock to prevent races with pkg_work_scheduled */

static spinlock_t pkg_work_lock;

static u16 max_phy_id;

/* Debug counters to show using debugfs */

static struct dentry *debugfs;

static unsigned int pkg_interrupt_cnt;

static unsigned int pkg_work_cnt;


static int pkg_temp_debugfs_init(void) { struct dentry *d; debugfs = debugfs_create_dir("pkg_temp_thermal", NULL); if (!debugfs) return -ENOENT; d = debugfs_create_u32("pkg_thres_interrupt", S_IRUGO, debugfs, (u32 *)&pkg_interrupt_cnt); if (!d) goto err_out; d = debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs, (u32 *)&pkg_work_cnt); if (!d) goto err_out; return 0; err_out: debugfs_remove_recursive(debugfs); return -ENOENT; }

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static struct phy_dev_entry *pkg_temp_thermal_get_phy_entry(unsigned int cpu) { u16 phys_proc_id = topology_physical_package_id(cpu); struct phy_dev_entry *phy_ptr; mutex_lock(&phy_dev_list_mutex); list_for_each_entry(phy_ptr, &phy_dev_list, list) if (phy_ptr->phys_proc_id == phys_proc_id) { mutex_unlock(&phy_dev_list_mutex); return phy_ptr; } mutex_unlock(&phy_dev_list_mutex); return NULL; }

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/* * tj-max is is interesting because threshold is set relative to this * temperature. */
static int get_tj_max(int cpu, u32 *tj_max) { u32 eax, edx; u32 val; int err; err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx); if (err) goto err_ret; else { val = (eax >> 16) & 0xff; if (val) *tj_max = val * 1000; else { err = -EINVAL; goto err_ret; } } return 0; err_ret: *tj_max = 0; return err; }

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static int sys_get_curr_temp(struct thermal_zone_device *tzd, int *temp) { u32 eax, edx; struct phy_dev_entry *phy_dev_entry; phy_dev_entry = tzd->devdata; rdmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_STATUS, &eax, &edx); if (eax & 0x80000000) { *temp = phy_dev_entry->tj_max - ((eax >> 16) & 0x7f) * 1000; pr_debug("sys_get_curr_temp %d\n", *temp); return 0; } return -EINVAL; }

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static int sys_get_trip_temp(struct thermal_zone_device *tzd, int trip, int *temp) { u32 eax, edx; struct phy_dev_entry *phy_dev_entry; u32 mask, shift; unsigned long thres_reg_value; int ret; if (trip >= MAX_NUMBER_OF_TRIPS) return -EINVAL; phy_dev_entry = tzd->devdata; if (trip) { mask = THERM_MASK_THRESHOLD1; shift = THERM_SHIFT_THRESHOLD1; } else { mask = THERM_MASK_THRESHOLD0; shift = THERM_SHIFT_THRESHOLD0; } ret = rdmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, &eax, &edx); if (ret < 0) return -EINVAL; thres_reg_value = (eax & mask) >> shift; if (thres_reg_value) *temp = phy_dev_entry->tj_max - thres_reg_value * 1000; else *temp = 0; pr_debug("sys_get_trip_temp %d\n", *temp); return 0; }

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static int sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp) { u32 l, h; struct phy_dev_entry *phy_dev_entry; u32 mask, shift, intr; int ret; phy_dev_entry = tzd->devdata; if (trip >= MAX_NUMBER_OF_TRIPS || temp >= phy_dev_entry->tj_max) return -EINVAL; ret = rdmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, &l, &h); if (ret < 0) return -EINVAL; if (trip) { mask = THERM_MASK_THRESHOLD1; shift = THERM_SHIFT_THRESHOLD1; intr = THERM_INT_THRESHOLD1_ENABLE; } else { mask = THERM_MASK_THRESHOLD0; shift = THERM_SHIFT_THRESHOLD0; intr = THERM_INT_THRESHOLD0_ENABLE; } l &= ~mask; /* * When users space sets a trip temperature == 0, which is indication * that, it is no longer interested in receiving notifications. */ if (!temp) l &= ~intr; else { l |= (phy_dev_entry->tj_max - temp)/1000 << shift; l |= intr; } return wrmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); }

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static int sys_get_trip_type(struct thermal_zone_device *thermal, int trip, enum thermal_trip_type *type) { *type = THERMAL_TRIP_PASSIVE; return 0; }

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/* Thermal zone callback registry */ static struct thermal_zone_device_ops tzone_ops = { .get_temp = sys_get_curr_temp, .get_trip_temp = sys_get_trip_temp, .get_trip_type = sys_get_trip_type, .set_trip_temp = sys_set_trip_temp, };
static bool pkg_temp_thermal_platform_thermal_rate_control(void) { return true; }

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/* Enable threshold interrupt on local package/cpu */
static inline void enable_pkg_thres_interrupt(void) { u32 l, h; u8 thres_0, thres_1; rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); /* only enable/disable if it had valid threshold value */ thres_0 = (l & THERM_MASK_THRESHOLD0) >> THERM_SHIFT_THRESHOLD0; thres_1 = (l & THERM_MASK_THRESHOLD1) >> THERM_SHIFT_THRESHOLD1; if (thres_0) l |= THERM_INT_THRESHOLD0_ENABLE; if (thres_1) l |= THERM_INT_THRESHOLD1_ENABLE; wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); }

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/* Disable threshold interrupt on local package/cpu */
static inline void disable_pkg_thres_interrupt(void) { u32 l, h; rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h); wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l & (~THERM_INT_THRESHOLD0_ENABLE) & (~THERM_INT_THRESHOLD1_ENABLE), h); }

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static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work) { __u64 msr_val; int cpu = smp_processor_id(); int phy_id = topology_physical_package_id(cpu); struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); bool notify = false; unsigned long flags; if (!phdev) return; spin_lock_irqsave(&pkg_work_lock, flags); ++pkg_work_cnt; if (unlikely(phy_id > max_phy_id)) { spin_unlock_irqrestore(&pkg_work_lock, flags); return; } pkg_work_scheduled[phy_id] = 0; spin_unlock_irqrestore(&pkg_work_lock, flags); enable_pkg_thres_interrupt(); rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val); if (msr_val & THERM_LOG_THRESHOLD0) { wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val & ~THERM_LOG_THRESHOLD0); notify = true; } if (msr_val & THERM_LOG_THRESHOLD1) { wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val & ~THERM_LOG_THRESHOLD1); notify = true; } if (notify) { pr_debug("thermal_zone_device_update\n"); thermal_zone_device_update(phdev->tzone, THERMAL_EVENT_UNSPECIFIED); } }

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static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) { unsigned long flags; int cpu = smp_processor_id(); int phy_id = topology_physical_package_id(cpu); /* * When a package is in interrupted state, all CPU's in that package * are in the same interrupt state. So scheduling on any one CPU in * the package is enough and simply return for others. */ spin_lock_irqsave(&pkg_work_lock, flags); ++pkg_interrupt_cnt; if (unlikely(phy_id > max_phy_id) || unlikely(!pkg_work_scheduled) || pkg_work_scheduled[phy_id]) { disable_pkg_thres_interrupt(); spin_unlock_irqrestore(&pkg_work_lock, flags); return -EINVAL; } pkg_work_scheduled[phy_id] = 1; spin_unlock_irqrestore(&pkg_work_lock, flags); disable_pkg_thres_interrupt(); schedule_delayed_work_on(cpu, &per_cpu(pkg_temp_thermal_threshold_work, cpu), msecs_to_jiffies(notify_delay_ms)); return 0; }

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static int find_siblings_cpu(int cpu) { int i; int id = topology_physical_package_id(cpu); for_each_online_cpu(i) if (i != cpu && topology_physical_package_id(i) == id) return i; return 0; }

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static int pkg_temp_thermal_device_add(unsigned int cpu) { int err; u32 tj_max; struct phy_dev_entry *phy_dev_entry; int thres_count; u32 eax, ebx, ecx, edx; u8 *temp; unsigned long flags; cpuid(6, &eax, &ebx, &ecx, &edx); thres_count = ebx & 0x07; if (!thres_count) return -ENODEV; if (topology_physical_package_id(cpu) > MAX_PKG_TEMP_ZONE_IDS) return -ENODEV; thres_count = clamp_val(thres_count, 0, MAX_NUMBER_OF_TRIPS); err = get_tj_max(cpu, &tj_max); if (err) goto err_ret; mutex_lock(&phy_dev_list_mutex); phy_dev_entry = kzalloc(sizeof(*phy_dev_entry), GFP_KERNEL); if (!phy_dev_entry) { err = -ENOMEM; goto err_ret_unlock; } spin_lock_irqsave(&pkg_work_lock, flags); if (topology_physical_package_id(cpu) > max_phy_id) max_phy_id = topology_physical_package_id(cpu); temp = krealloc(pkg_work_scheduled, (max_phy_id+1) * sizeof(u8), GFP_ATOMIC); if (!temp) { spin_unlock_irqrestore(&pkg_work_lock, flags); err = -ENOMEM; goto err_ret_free; } pkg_work_scheduled = temp; pkg_work_scheduled[topology_physical_package_id(cpu)] = 0; spin_unlock_irqrestore(&pkg_work_lock, flags); phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu); phy_dev_entry->first_cpu = cpu; phy_dev_entry->tj_max = tj_max; phy_dev_entry->ref_cnt = 1; phy_dev_entry->tzone = thermal_zone_device_register("x86_pkg_temp", thres_count, (thres_count == MAX_NUMBER_OF_TRIPS) ? 0x03 : 0x01, phy_dev_entry, &tzone_ops, &pkg_temp_tz_params, 0, 0); if (IS_ERR(phy_dev_entry->tzone)) { err = PTR_ERR(phy_dev_entry->tzone); goto err_ret_free; } /* Store MSR value for package thermal interrupt, to restore at exit */ rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, &phy_dev_entry->start_pkg_therm_low, &phy_dev_entry->start_pkg_therm_high); list_add_tail(&phy_dev_entry->list, &phy_dev_list); pr_debug("pkg_temp_thermal_device_add :phy_id %d cpu %d\n", phy_dev_entry->phys_proc_id, cpu); mutex_unlock(&phy_dev_list_mutex); return 0; err_ret_free: kfree(phy_dev_entry); err_ret_unlock: mutex_unlock(&phy_dev_list_mutex); err_ret: return err; }

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static int pkg_temp_thermal_device_remove(unsigned int cpu) { struct phy_dev_entry *n; u16 phys_proc_id = topology_physical_package_id(cpu); struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); if (!phdev) return -ENODEV; mutex_lock(&phy_dev_list_mutex); /* If we are loosing the first cpu for this package, we need change */ if (phdev->first_cpu == cpu) { phdev->first_cpu = find_siblings_cpu(cpu); pr_debug("thermal_device_remove: first cpu switched %d\n", phdev->first_cpu); } /* * It is possible that no siblings left as this was the last cpu * going offline. We don't need to worry about this assignment * as the phydev entry will be removed in this case and * thermal zone is removed. */ --phdev->ref_cnt; pr_debug("thermal_device_remove: pkg: %d cpu %d ref_cnt %d\n", phys_proc_id, cpu, phdev->ref_cnt); if (!phdev->ref_cnt) list_for_each_entry_safe(phdev, n, &phy_dev_list, list) { if (phdev->phys_proc_id == phys_proc_id) { thermal_zone_device_unregister(phdev->tzone); list_del(&phdev->list); kfree(phdev); break; } } mutex_unlock(&phy_dev_list_mutex); return 0; }

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static int get_core_online(unsigned int cpu) { struct cpuinfo_x86 *c = &cpu_data(cpu); struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); /* Check if there is already an instance for this package */ if (!phdev) { if (!cpu_has(c, X86_FEATURE_DTHERM) || !cpu_has(c, X86_FEATURE_PTS)) return -ENODEV; if (pkg_temp_thermal_device_add(cpu)) return -ENODEV; } else { mutex_lock(&phy_dev_list_mutex); ++phdev->ref_cnt; pr_debug("get_core_online: cpu %d ref_cnt %d\n", cpu, phdev->ref_cnt); mutex_unlock(&phy_dev_list_mutex); } INIT_DELAYED_WORK(&per_cpu(pkg_temp_thermal_threshold_work, cpu), pkg_temp_thermal_threshold_work_fn); pr_debug("get_core_online: cpu %d successful\n", cpu); return 0; }

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static void put_core_offline(unsigned int cpu) { if (!pkg_temp_thermal_device_remove(cpu)) cancel_delayed_work_sync( &per_cpu(pkg_temp_thermal_threshold_work, cpu)); pr_debug("put_core_offline: cpu %d\n", cpu); }

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static int pkg_temp_thermal_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long) hcpu; switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: get_core_online(cpu); break; case CPU_DOWN_PREPARE: put_core_offline(cpu); break; } return NOTIFY_OK; }

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static struct notifier_block pkg_temp_thermal_notifier __refdata = { .notifier_call = pkg_temp_thermal_cpu_callback, }; static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = { { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_PTS }, {} }; MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
static int __init pkg_temp_thermal_init(void) { int i; if (!x86_match_cpu(pkg_temp_thermal_ids)) return -ENODEV; spin_lock_init(&pkg_work_lock); platform_thermal_package_notify = pkg_temp_thermal_platform_thermal_notify; platform_thermal_package_rate_control = pkg_temp_thermal_platform_thermal_rate_control; cpu_notifier_register_begin(); for_each_online_cpu(i) if (get_core_online(i)) goto err_ret; __register_hotcpu_notifier(&pkg_temp_thermal_notifier); cpu_notifier_register_done(); pkg_temp_debugfs_init(); /* Don't care if fails */ return 0; err_ret: for_each_online_cpu(i) put_core_offline(i); cpu_notifier_register_done(); kfree(pkg_work_scheduled); platform_thermal_package_notify = NULL; platform_thermal_package_rate_control = NULL; return -ENODEV; }

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static void __exit pkg_temp_thermal_exit(void) { struct phy_dev_entry *phdev, *n; int i; cpu_notifier_register_begin(); __unregister_hotcpu_notifier(&pkg_temp_thermal_notifier); mutex_lock(&phy_dev_list_mutex); list_for_each_entry_safe(phdev, n, &phy_dev_list, list) { /* Retore old MSR value for package thermal interrupt */ wrmsr_on_cpu(phdev->first_cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT, phdev->start_pkg_therm_low, phdev->start_pkg_therm_high); thermal_zone_device_unregister(phdev->tzone); list_del(&phdev->list); kfree(phdev); } mutex_unlock(&phy_dev_list_mutex); platform_thermal_package_notify = NULL; platform_thermal_package_rate_control = NULL; for_each_online_cpu(i) cancel_delayed_work_sync( &per_cpu(pkg_temp_thermal_threshold_work, i)); cpu_notifier_register_done(); kfree(pkg_work_scheduled); debugfs_remove_recursive(debugfs); }

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module_init(pkg_temp_thermal_init) module_exit(pkg_temp_thermal_exit) MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver"); MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>"); MODULE_LICENSE("GPL v2");

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Directory: drivers/thermal