// SPDX-License-Identifier: GPL-2.0-only /* * via-cputemp.c - Driver for VIA CPU core temperature monitoring * Copyright (C) 2009 VIA Technologies, Inc. * * based on existing coretemp.c, which is * * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/hwmon.h> #include <linux/hwmon-vid.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 <asm/msr.h> #include <asm/processor.h> #include <asm/cpu_device_id.h> #define DRVNAME "via_cputemp" enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME }; /* * Functions declaration */ struct via_cputemp_data { struct device *hwmon_dev; const char *name; u8 vrm; u32 id; u32 msr_temp; u32 msr_vid; }; /* * Sysfs stuff */ static ssize_t name_show(struct device *dev, struct device_attribute *devattr, char *buf) { int ret; struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); struct via_cputemp_data *data = dev_get_drvdata(dev); if (attr->index == SHOW_NAME) ret = sprintf(buf, "%s\n", data->name); else /* show label */ ret = sprintf(buf, "Core %d\n", data->id); return ret; } static ssize_t temp_show(struct device *dev, struct device_attribute *devattr, char *buf) { struct via_cputemp_data *data = dev_get_drvdata(dev); u32 eax, edx; int err; err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); if (err) return -EAGAIN; return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000); } static ssize_t cpu0_vid_show(struct device *dev, struct device_attribute *devattr, char *buf) { struct via_cputemp_data *data = dev_get_drvdata(dev); u32 eax, edx; int err; err = rdmsr_safe_on_cpu(data->id, data->msr_vid, &eax, &edx); if (err) return -EAGAIN; return sprintf(buf, "%d\n", vid_from_reg(~edx & 0x7f, data->vrm)); } static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, SHOW_TEMP); static SENSOR_DEVICE_ATTR_RO(temp1_label, name, SHOW_LABEL); static SENSOR_DEVICE_ATTR_RO(name, name, SHOW_NAME); static struct attribute *via_cputemp_attributes[] = { &sensor_dev_attr_name.dev_attr.attr, &sensor_dev_attr_temp1_label.dev_attr.attr, &sensor_dev_attr_temp1_input.dev_attr.attr, NULL }; static const struct attribute_group via_cputemp_group = { .attrs = via_cputemp_attributes, }; /* Optional attributes */ static DEVICE_ATTR_RO(cpu0_vid); static int via_cputemp_probe(struct platform_device *pdev) { struct via_cputemp_data *data; struct cpuinfo_x86 *c = &cpu_data(pdev->id); int err; u32 eax, edx; data = devm_kzalloc(&pdev->dev, sizeof(struct via_cputemp_data), GFP_KERNEL); if (!data) return -ENOMEM; data->id = pdev->id; data->name = "via_cputemp"; if (c->x86 == 7) { data->msr_temp = 0x1423; } else { switch (c->x86_model) { case 0xA: /* C7 A */ case 0xD: /* C7 D */ data->msr_temp = 0x1169; data->msr_vid = 0x198; break; case 0xF: /* Nano */ data->msr_temp = 0x1423; break; default: return -ENODEV; } } /* test if we can access the TEMPERATURE MSR */ err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx); if (err) { dev_err(&pdev->dev, "Unable to access TEMPERATURE MSR, giving up\n"); return err; } platform_set_drvdata(pdev, data); err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group); if (err) return err; if (data->msr_vid) data->vrm = vid_which_vrm(); if (data->vrm) { err = device_create_file(&pdev->dev, &dev_attr_cpu0_vid); if (err) goto exit_remove; } data->hwmon_dev = hwmon_device_register(&pdev->dev); if (IS_ERR(data->hwmon_dev)) { err = PTR_ERR(data->hwmon_dev); dev_err(&pdev->dev, "Class registration failed (%d)\n", err); goto exit_remove; } return 0; exit_remove: if (data->vrm) device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); return err; } static int via_cputemp_remove(struct platform_device *pdev) { struct via_cputemp_data *data = platform_get_drvdata(pdev); hwmon_device_unregister(data->hwmon_dev); if (data->vrm) device_remove_file(&pdev->dev, &dev_attr_cpu0_vid); sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group); return 0; } static struct platform_driver via_cputemp_driver = { .driver = { .name = DRVNAME, }, .probe = via_cputemp_probe, .remove = via_cputemp_remove, }; struct pdev_entry { struct list_head list; struct platform_device *pdev; unsigned int cpu; }; static LIST_HEAD(pdev_list); static DEFINE_MUTEX(pdev_list_mutex); static int via_cputemp_online(unsigned int cpu) { int err; struct platform_device *pdev; struct pdev_entry *pdev_entry; pdev = platform_device_alloc(DRVNAME, cpu); if (!pdev) { err = -ENOMEM; pr_err("Device allocation failed\n"); goto exit; } pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL); if (!pdev_entry) { err = -ENOMEM; goto exit_device_put; } err = platform_device_add(pdev); if (err) { pr_err("Device addition failed (%d)\n", err); goto exit_device_free; } pdev_entry->pdev = pdev; pdev_entry->cpu = cpu; mutex_lock(&pdev_list_mutex); list_add_tail(&pdev_entry->list, &pdev_list); mutex_unlock(&pdev_list_mutex); return 0; exit_device_free: kfree(pdev_entry); exit_device_put: platform_device_put(pdev); exit: return err; } static int via_cputemp_down_prep(unsigned int cpu) { struct pdev_entry *p; mutex_lock(&pdev_list_mutex); list_for_each_entry(p, &pdev_list, list) { if (p->cpu == cpu) { platform_device_unregister(p->pdev); list_del(&p->list); mutex_unlock(&pdev_list_mutex); kfree(p); return 0; } } mutex_unlock(&pdev_list_mutex); return 0; } static const struct x86_cpu_id __initconst cputemp_ids[] = { { X86_VENDOR_CENTAUR, 6, 0xa, }, /* C7 A */ { X86_VENDOR_CENTAUR, 6, 0xd, }, /* C7 D */ { X86_VENDOR_CENTAUR, 6, 0xf, }, /* Nano */ { X86_VENDOR_CENTAUR, 7, X86_MODEL_ANY, }, {} }; MODULE_DEVICE_TABLE(x86cpu, cputemp_ids); static enum cpuhp_state via_temp_online; static int __init via_cputemp_init(void) { int err; if (!x86_match_cpu(cputemp_ids)) return -ENODEV; err = platform_driver_register(&via_cputemp_driver); if (err) goto exit; err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hwmon/via:online", via_cputemp_online, via_cputemp_down_prep); if (err < 0) goto exit_driver_unreg; via_temp_online = err; #ifndef CONFIG_HOTPLUG_CPU if (list_empty(&pdev_list)) { err = -ENODEV; goto exit_hp_unreg; } #endif return 0; #ifndef CONFIG_HOTPLUG_CPU exit_hp_unreg: cpuhp_remove_state_nocalls(via_temp_online); #endif exit_driver_unreg: platform_driver_unregister(&via_cputemp_driver); exit: return err; } static void __exit via_cputemp_exit(void) { cpuhp_remove_state(via_temp_online); platform_driver_unregister(&via_cputemp_driver); } MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>"); MODULE_DESCRIPTION("VIA CPU temperature monitor"); MODULE_LICENSE("GPL"); module_init(via_cputemp_init) module_exit(via_cputemp_exit)