blob: ccf0af5b988a7c37fa91e8ed2361ac83689c67b3 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* coretemp.c - Linux kernel module for hardware monitoring
*
* Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
*
* Inspired from many hwmon drivers
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/hwmon.h>
#include <linux/sysfs.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/cpu_device_id.h>
#define DRVNAME "coretemp"
/*
* force_tjmax only matters when TjMax can't be read from the CPU itself.
* When set, it replaces the driver's suboptimal heuristic.
*/
static int force_tjmax;
module_param_named(tjmax, force_tjmax, int, 0444);
MODULE_PARM_DESC(tjmax, "TjMax value in degrees Celsius");
#define PKG_SYSFS_ATTR_NO 1 /* Sysfs attribute for package temp */
#define BASE_SYSFS_ATTR_NO 2 /* Sysfs Base attr no for coretemp */
#define NUM_REAL_CORES 128 /* Number of Real cores per cpu */
#define CORETEMP_NAME_LENGTH 19 /* String Length of attrs */
#define MAX_CORE_ATTRS 4 /* Maximum no of basic attrs */
#define TOTAL_ATTRS (MAX_CORE_ATTRS + 1)
#define MAX_CORE_DATA (NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)
#define TO_CORE_ID(cpu) (cpu_data(cpu).cpu_core_id)
#define TO_ATTR_NO(cpu) (TO_CORE_ID(cpu) + BASE_SYSFS_ATTR_NO)
#ifdef CONFIG_SMP
#define for_each_sibling(i, cpu) \
for_each_cpu(i, topology_sibling_cpumask(cpu))
#else
#define for_each_sibling(i, cpu) for (i = 0; false; )
#endif
/*
* Per-Core Temperature Data
* @last_updated: The time when the current temperature value was updated
* earlier (in jiffies).
* @cpu_core_id: The CPU Core from which temperature values should be read
* This value is passed as "id" field to rdmsr/wrmsr functions.
* @status_reg: One of IA32_THERM_STATUS or IA32_PACKAGE_THERM_STATUS,
* from where the temperature values should be read.
* @attr_size: Total number of pre-core attrs displayed in the sysfs.
* @is_pkg_data: If this is 1, the temp_data holds pkgtemp data.
* Otherwise, temp_data holds coretemp data.
* @valid: If this is 1, the current temperature is valid.
*/
struct temp_data {
int temp;
int ttarget;
int tjmax;
unsigned long last_updated;
unsigned int cpu;
u32 cpu_core_id;
u32 status_reg;
int attr_size;
bool is_pkg_data;
bool valid;
struct sensor_device_attribute sd_attrs[TOTAL_ATTRS];
char attr_name[TOTAL_ATTRS][CORETEMP_NAME_LENGTH];
struct attribute *attrs[TOTAL_ATTRS + 1];
struct attribute_group attr_group;
struct mutex update_lock;
};
/* Platform Data per Physical CPU */
struct platform_data {
struct device *hwmon_dev;
u16 pkg_id;
struct cpumask cpumask;
struct temp_data *core_data[MAX_CORE_DATA];
struct device_attribute name_attr;
};
/* Keep track of how many zone pointers we allocated in init() */
static int max_zones __read_mostly;
/* Array of zone pointers. Serialized by cpu hotplug lock */
static struct platform_device **zone_devices;
static ssize_t show_label(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct platform_data *pdata = dev_get_drvdata(dev);
struct temp_data *tdata = pdata->core_data[attr->index];
if (tdata->is_pkg_data)
return sprintf(buf, "Package id %u\n", pdata->pkg_id);
return sprintf(buf, "Core %u\n", tdata->cpu_core_id);
}
static ssize_t show_crit_alarm(struct device *dev,
struct device_attribute *devattr, char *buf)
{
u32 eax, edx;
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct platform_data *pdata = dev_get_drvdata(dev);
struct temp_data *tdata = pdata->core_data[attr->index];
mutex_lock(&tdata->update_lock);
rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
mutex_unlock(&tdata->update_lock);
return sprintf(buf, "%d\n", (eax >> 5) & 1);
}
static ssize_t show_tjmax(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct platform_data *pdata = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", pdata->core_data[attr->index]->tjmax);
}
static ssize_t show_ttarget(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct platform_data *pdata = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);
}
static ssize_t show_temp(struct device *dev,
struct device_attribute *devattr, char *buf)
{
u32 eax, edx;
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct platform_data *pdata = dev_get_drvdata(dev);
struct temp_data *tdata = pdata->core_data[attr->index];
mutex_lock(&tdata->update_lock);
/* Check whether the time interval has elapsed */
if (!tdata->valid || time_after(jiffies, tdata->last_updated + HZ)) {
rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
/*
* Ignore the valid bit. In all observed cases the register
* value is either low or zero if the valid bit is 0.
* Return it instead of reporting an error which doesn't
* really help at all.
*/
tdata->temp = tdata->tjmax - ((eax >> 16) & 0x7f) * 1000;
tdata->valid = true;
tdata->last_updated = jiffies;
}
mutex_unlock(&tdata->update_lock);
return sprintf(buf, "%d\n", tdata->temp);
}
struct tjmax_pci {
unsigned int device;
int tjmax;
};
static const struct tjmax_pci tjmax_pci_table[] = {
{ 0x0708, 110000 }, /* CE41x0 (Sodaville ) */
{ 0x0c72, 102000 }, /* Atom S1240 (Centerton) */
{ 0x0c73, 95000 }, /* Atom S1220 (Centerton) */
{ 0x0c75, 95000 }, /* Atom S1260 (Centerton) */
};
struct tjmax {
char const *id;
int tjmax;
};
static const struct tjmax tjmax_table[] = {
{ "CPU 230", 100000 }, /* Model 0x1c, stepping 2 */
{ "CPU 330", 125000 }, /* Model 0x1c, stepping 2 */
};
struct tjmax_model {
u8 model;
u8 mask;
int tjmax;
};
#define ANY 0xff
static const struct tjmax_model tjmax_model_table[] = {
{ 0x1c, 10, 100000 }, /* D4xx, K4xx, N4xx, D5xx, K5xx, N5xx */
{ 0x1c, ANY, 90000 }, /* Z5xx, N2xx, possibly others
* Note: Also matches 230 and 330,
* which are covered by tjmax_table
*/
{ 0x26, ANY, 90000 }, /* Atom Tunnel Creek (Exx), Lincroft (Z6xx)
* Note: TjMax for E6xxT is 110C, but CPU type
* is undetectable by software
*/
{ 0x27, ANY, 90000 }, /* Atom Medfield (Z2460) */
{ 0x35, ANY, 90000 }, /* Atom Clover Trail/Cloverview (Z27x0) */
{ 0x36, ANY, 100000 }, /* Atom Cedar Trail/Cedarview (N2xxx, D2xxx)
* Also matches S12x0 (stepping 9), covered by
* PCI table
*/
};
static int adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
{
/* The 100C is default for both mobile and non mobile CPUs */
int tjmax = 100000;
int tjmax_ee = 85000;
int usemsr_ee = 1;
int err;
u32 eax, edx;
int i;
u16 devfn = PCI_DEVFN(0, 0);
struct pci_dev *host_bridge = pci_get_domain_bus_and_slot(0, 0, devfn);
/*
* Explicit tjmax table entries override heuristics.
* First try PCI host bridge IDs, followed by model ID strings
* and model/stepping information.
*/
if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL) {
for (i = 0; i < ARRAY_SIZE(tjmax_pci_table); i++) {
if (host_bridge->device == tjmax_pci_table[i].device)
return tjmax_pci_table[i].tjmax;
}
}
for (i = 0; i < ARRAY_SIZE(tjmax_table); i++) {
if (strstr(c->x86_model_id, tjmax_table[i].id))
return tjmax_table[i].tjmax;
}
for (i = 0; i < ARRAY_SIZE(tjmax_model_table); i++) {
const struct tjmax_model *tm = &tjmax_model_table[i];
if (c->x86_model == tm->model &&
(tm->mask == ANY || c->x86_stepping == tm->mask))
return tm->tjmax;
}
/* Early chips have no MSR for TjMax */
if (c->x86_model == 0xf && c->x86_stepping < 4)
usemsr_ee = 0;
if (c->x86_model > 0xe && usemsr_ee) {
u8 platform_id;
/*
* Now we can detect the mobile CPU using Intel provided table
* http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
* For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
*/
err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
if (err) {
dev_warn(dev,
"Unable to access MSR 0x17, assuming desktop"
" CPU\n");
usemsr_ee = 0;
} else if (c->x86_model < 0x17 && !(eax & 0x10000000)) {
/*
* Trust bit 28 up to Penryn, I could not find any
* documentation on that; if you happen to know
* someone at Intel please ask
*/
usemsr_ee = 0;
} else {
/* Platform ID bits 52:50 (EDX starts at bit 32) */
platform_id = (edx >> 18) & 0x7;
/*
* Mobile Penryn CPU seems to be platform ID 7 or 5
* (guesswork)
*/
if (c->x86_model == 0x17 &&
(platform_id == 5 || platform_id == 7)) {
/*
* If MSR EE bit is set, set it to 90 degrees C,
* otherwise 105 degrees C
*/
tjmax_ee = 90000;
tjmax = 105000;
}
}
}
if (usemsr_ee) {
err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
if (err) {
dev_warn(dev,
"Unable to access MSR 0xEE, for Tjmax, left"
" at default\n");
} else if (eax & 0x40000000) {
tjmax = tjmax_ee;
}
} else if (tjmax == 100000) {
/*
* If we don't use msr EE it means we are desktop CPU
* (with exeception of Atom)
*/
dev_warn(dev, "Using relative temperature scale!\n");
}
return tjmax;
}
static bool cpu_has_tjmax(struct cpuinfo_x86 *c)
{
u8 model = c->x86_model;
return model > 0xe &&
model != 0x1c &&
model != 0x26 &&
model != 0x27 &&
model != 0x35 &&
model != 0x36;
}
static int get_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
{
int err;
u32 eax, edx;
u32 val;
/*
* A new feature of current Intel(R) processors, the
* IA32_TEMPERATURE_TARGET contains the TjMax value
*/
err = rdmsr_safe_on_cpu(id, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
if (err) {
if (cpu_has_tjmax(c))
dev_warn(dev, "Unable to read TjMax from CPU %u\n", id);
} else {
val = (eax >> 16) & 0xff;
/*
* If the TjMax is not plausible, an assumption
* will be used
*/
if (val) {
dev_dbg(dev, "TjMax is %d degrees C\n", val);
return val * 1000;
}
}
if (force_tjmax) {
dev_notice(dev, "TjMax forced to %d degrees C by user\n",
force_tjmax);
return force_tjmax * 1000;
}
/*
* An assumption is made for early CPUs and unreadable MSR.
* NOTE: the calculated value may not be correct.
*/
return adjust_tjmax(c, id, dev);
}
static int create_core_attrs(struct temp_data *tdata, struct device *dev,
int attr_no)
{
int i;
static ssize_t (*const rd_ptr[TOTAL_ATTRS]) (struct device *dev,
struct device_attribute *devattr, char *buf) = {
show_label, show_crit_alarm, show_temp, show_tjmax,
show_ttarget };
static const char *const suffixes[TOTAL_ATTRS] = {
"label", "crit_alarm", "input", "crit", "max"
};
for (i = 0; i < tdata->attr_size; i++) {
snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH,
"temp%d_%s", attr_no, suffixes[i]);
sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
tdata->sd_attrs[i].dev_attr.attr.mode = 0444;
tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
tdata->sd_attrs[i].index = attr_no;
tdata->attrs[i] = &tdata->sd_attrs[i].dev_attr.attr;
}
tdata->attr_group.attrs = tdata->attrs;
return sysfs_create_group(&dev->kobj, &tdata->attr_group);
}
static int chk_ucode_version(unsigned int cpu)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);
/*
* Check if we have problem with errata AE18 of Core processors:
* Readings might stop update when processor visited too deep sleep,
* fixed for stepping D0 (6EC).
*/
if (c->x86_model == 0xe && c->x86_stepping < 0xc && c->microcode < 0x39) {
pr_err("Errata AE18 not fixed, update BIOS or microcode of the CPU!\n");
return -ENODEV;
}
return 0;
}
static struct platform_device *coretemp_get_pdev(unsigned int cpu)
{
int id = topology_logical_die_id(cpu);
if (id >= 0 && id < max_zones)
return zone_devices[id];
return NULL;
}
static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
{
struct temp_data *tdata;
tdata = kzalloc(sizeof(struct temp_data), GFP_KERNEL);
if (!tdata)
return NULL;
tdata->status_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_STATUS :
MSR_IA32_THERM_STATUS;
tdata->is_pkg_data = pkg_flag;
tdata->cpu = cpu;
tdata->cpu_core_id = TO_CORE_ID(cpu);
tdata->attr_size = MAX_CORE_ATTRS;
mutex_init(&tdata->update_lock);
return tdata;
}
static int create_core_data(struct platform_device *pdev, unsigned int cpu,
int pkg_flag)
{
struct temp_data *tdata;
struct platform_data *pdata = platform_get_drvdata(pdev);
struct cpuinfo_x86 *c = &cpu_data(cpu);
u32 eax, edx;
int err, attr_no;
/*
* Find attr number for sysfs:
* We map the attr number to core id of the CPU
* The attr number is always core id + 2
* The Pkgtemp will always show up as temp1_*, if available
*/
attr_no = pkg_flag ? PKG_SYSFS_ATTR_NO : TO_ATTR_NO(cpu);
if (attr_no > MAX_CORE_DATA - 1)
return -ERANGE;
tdata = init_temp_data(cpu, pkg_flag);
if (!tdata)
return -ENOMEM;
/* Test if we can access the status register */
err = rdmsr_safe_on_cpu(cpu, tdata->status_reg, &eax, &edx);
if (err)
goto exit_free;
/* We can access status register. Get Critical Temperature */
tdata->tjmax = get_tjmax(c, cpu, &pdev->dev);
/*
* Read the still undocumented bits 8:15 of IA32_TEMPERATURE_TARGET.
* The target temperature is available on older CPUs but not in this
* register. Atoms don't have the register at all.
*/
if (c->x86_model > 0xe && c->x86_model != 0x1c) {
err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET,
&eax, &edx);
if (!err) {
tdata->ttarget
= tdata->tjmax - ((eax >> 8) & 0xff) * 1000;
tdata->attr_size++;
}
}
pdata->core_data[attr_no] = tdata;
/* Create sysfs interfaces */
err = create_core_attrs(tdata, pdata->hwmon_dev, attr_no);
if (err)
goto exit_free;
return 0;
exit_free:
pdata->core_data[attr_no] = NULL;
kfree(tdata);
return err;
}
static void
coretemp_add_core(struct platform_device *pdev, unsigned int cpu, int pkg_flag)
{
if (create_core_data(pdev, cpu, pkg_flag))
dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
}
static void coretemp_remove_core(struct platform_data *pdata, int indx)
{
struct temp_data *tdata = pdata->core_data[indx];
/* Remove the sysfs attributes */
sysfs_remove_group(&pdata->hwmon_dev->kobj, &tdata->attr_group);
kfree(pdata->core_data[indx]);
pdata->core_data[indx] = NULL;
}
static int coretemp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct platform_data *pdata;
/* Initialize the per-zone data structures */
pdata = devm_kzalloc(dev, sizeof(struct platform_data), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
pdata->pkg_id = pdev->id;
platform_set_drvdata(pdev, pdata);
pdata->hwmon_dev = devm_hwmon_device_register_with_groups(dev, DRVNAME,
pdata, NULL);
return PTR_ERR_OR_ZERO(pdata->hwmon_dev);
}
static int coretemp_remove(struct platform_device *pdev)
{
struct platform_data *pdata = platform_get_drvdata(pdev);
int i;
for (i = MAX_CORE_DATA - 1; i >= 0; --i)
if (pdata->core_data[i])
coretemp_remove_core(pdata, i);
return 0;
}
static struct platform_driver coretemp_driver = {
.driver = {
.name = DRVNAME,
},
.probe = coretemp_probe,
.remove = coretemp_remove,
};
static struct platform_device *coretemp_device_add(unsigned int cpu)
{
int err, zoneid = topology_logical_die_id(cpu);
struct platform_device *pdev;
if (zoneid < 0)
return ERR_PTR(-ENOMEM);
pdev = platform_device_alloc(DRVNAME, zoneid);
if (!pdev)
return ERR_PTR(-ENOMEM);
err = platform_device_add(pdev);
if (err) {
platform_device_put(pdev);
return ERR_PTR(err);
}
zone_devices[zoneid] = pdev;
return pdev;
}
static int coretemp_cpu_online(unsigned int cpu)
{
struct platform_device *pdev = coretemp_get_pdev(cpu);
struct cpuinfo_x86 *c = &cpu_data(cpu);
struct platform_data *pdata;
/*
* Don't execute this on resume as the offline callback did
* not get executed on suspend.
*/
if (cpuhp_tasks_frozen)
return 0;
/*
* CPUID.06H.EAX[0] indicates whether the CPU has thermal
* sensors. We check this bit only, all the early CPUs
* without thermal sensors will be filtered out.
*/
if (!cpu_has(c, X86_FEATURE_DTHERM))
return -ENODEV;
if (!pdev) {
/* Check the microcode version of the CPU */
if (chk_ucode_version(cpu))
return -EINVAL;
/*
* Alright, we have DTS support.
* We are bringing the _first_ core in this pkg
* online. So, initialize per-pkg data structures and
* then bring this core online.
*/
pdev = coretemp_device_add(cpu);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
/*
* Check whether pkgtemp support is available.
* If so, add interfaces for pkgtemp.
*/
if (cpu_has(c, X86_FEATURE_PTS))
coretemp_add_core(pdev, cpu, 1);
}
pdata = platform_get_drvdata(pdev);
/*
* Check whether a thread sibling is already online. If not add the
* interface for this CPU core.
*/
if (!cpumask_intersects(&pdata->cpumask, topology_sibling_cpumask(cpu)))
coretemp_add_core(pdev, cpu, 0);
cpumask_set_cpu(cpu, &pdata->cpumask);
return 0;
}
static int coretemp_cpu_offline(unsigned int cpu)
{
struct platform_device *pdev = coretemp_get_pdev(cpu);
struct platform_data *pd;
struct temp_data *tdata;
int indx, target;
/*
* Don't execute this on suspend as the device remove locks
* up the machine.
*/
if (cpuhp_tasks_frozen)
return 0;
/* If the physical CPU device does not exist, just return */
if (!pdev)
return 0;
/* The core id is too big, just return */
indx = TO_ATTR_NO(cpu);
if (indx > MAX_CORE_DATA - 1)
return 0;
pd = platform_get_drvdata(pdev);
tdata = pd->core_data[indx];
cpumask_clear_cpu(cpu, &pd->cpumask);
/*
* If this is the last thread sibling, remove the CPU core
* interface, If there is still a sibling online, transfer the
* target cpu of that core interface to it.
*/
target = cpumask_any_and(&pd->cpumask, topology_sibling_cpumask(cpu));
if (target >= nr_cpu_ids) {
coretemp_remove_core(pd, indx);
} else if (tdata && tdata->cpu == cpu) {
mutex_lock(&tdata->update_lock);
tdata->cpu = target;
mutex_unlock(&tdata->update_lock);
}
/*
* If all cores in this pkg are offline, remove the device. This
* will invoke the platform driver remove function, which cleans up
* the rest.
*/
if (cpumask_empty(&pd->cpumask)) {
zone_devices[topology_logical_die_id(cpu)] = NULL;
platform_device_unregister(pdev);
return 0;
}
/*
* Check whether this core is the target for the package
* interface. We need to assign it to some other cpu.
*/
tdata = pd->core_data[PKG_SYSFS_ATTR_NO];
if (tdata && tdata->cpu == cpu) {
target = cpumask_first(&pd->cpumask);
mutex_lock(&tdata->update_lock);
tdata->cpu = target;
mutex_unlock(&tdata->update_lock);
}
return 0;
}
static const struct x86_cpu_id __initconst coretemp_ids[] = {
X86_MATCH_VENDOR_FEATURE(INTEL, X86_FEATURE_DTHERM, NULL),
{}
};
MODULE_DEVICE_TABLE(x86cpu, coretemp_ids);
static enum cpuhp_state coretemp_hp_online;
static int __init coretemp_init(void)
{
int err;
/*
* CPUID.06H.EAX[0] indicates whether the CPU has thermal
* sensors. We check this bit only, all the early CPUs
* without thermal sensors will be filtered out.
*/
if (!x86_match_cpu(coretemp_ids))
return -ENODEV;
max_zones = topology_max_packages() * topology_max_die_per_package();
zone_devices = kcalloc(max_zones, sizeof(struct platform_device *),
GFP_KERNEL);
if (!zone_devices)
return -ENOMEM;
err = platform_driver_register(&coretemp_driver);
if (err)
goto outzone;
err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hwmon/coretemp:online",
coretemp_cpu_online, coretemp_cpu_offline);
if (err < 0)
goto outdrv;
coretemp_hp_online = err;
return 0;
outdrv:
platform_driver_unregister(&coretemp_driver);
outzone:
kfree(zone_devices);
return err;
}
module_init(coretemp_init)
static void __exit coretemp_exit(void)
{
cpuhp_remove_state(coretemp_hp_online);
platform_driver_unregister(&coretemp_driver);
kfree(zone_devices);
}
module_exit(coretemp_exit)
MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
MODULE_DESCRIPTION("Intel Core temperature monitor");
MODULE_LICENSE("GPL");