// 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 = 1; 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");