zhaoxin inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I52DS7
CVE: NA

Add support for the temperature sensor inside CPU.
Supported are all known variants of the Zhaoxin processors.

Signed-off-by: LeoLiu-oc <LeoLiu-oc@zhaoxin.com>
---
 drivers/hwmon/Kconfig           |   9 +
 drivers/hwmon/Makefile          |   1 +
 drivers/hwmon/via-cputemp.c     |   1 -
 drivers/hwmon/zhaoxin-cputemp.c | 292 ++++++++++++++++++++++++++++++++
 4 files changed, 302 insertions(+), 1 deletion(-)
 create mode 100644 drivers/hwmon/zhaoxin-cputemp.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 0c2b032ee617..c11c3c46898a 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1889,6 +1889,15 @@ config SENSORS_VIA_CPUTEMP
       sensor inside your CPU. Supported are all known variants of
       the VIA C7 and Nano.

+config SENSORS_ZHAOXIN_CPUTEMP
+    tristate "Zhaoxin CPU temperature sensor"
+    depends on X86
+    select HWMON_VID
+    help
+      If you say yes here you get support for the temperature
+      sensor inside your CPU. Supported are all known variants of
+      the Zhaoxin processors.
+
 config SENSORS_VIA686A
     tristate "VIA686A"
     depends on PCI
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 9db2903b61e5..2427687972c9 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -184,6 +184,7 @@ obj-$(CONFIG_SENSORS_TMP421)    += tmp421.o
 obj-$(CONFIG_SENSORS_TMP513)    += tmp513.o
 obj-$(CONFIG_SENSORS_VEXPRESS)    += vexpress-hwmon.o
 obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
+obj-$(CONFIG_SENSORS_ZHAOXIN_CPUTEMP)    += zhaoxin-cputemp.o
 obj-$(CONFIG_SENSORS_VIA686A)    += via686a.o
 obj-$(CONFIG_SENSORS_VT1211)    += vt1211.o
 obj-$(CONFIG_SENSORS_VT8231)    += vt8231.o
diff --git a/drivers/hwmon/via-cputemp.c b/drivers/hwmon/via-cputemp.c
index e5d18dac8ee7..0a5057dbe51a 100644
--- a/drivers/hwmon/via-cputemp.c
+++ b/drivers/hwmon/via-cputemp.c
@@ -273,7 +273,6 @@ static const struct x86_cpu_id __initconst cputemp_ids[] = {
     X86_MATCH_VENDOR_FAM_MODEL(CENTAUR, 6, X86_CENTAUR_FAM6_C7_A,    NULL),
     X86_MATCH_VENDOR_FAM_MODEL(CENTAUR, 6, X86_CENTAUR_FAM6_C7_D,    NULL),
     X86_MATCH_VENDOR_FAM_MODEL(CENTAUR, 6, X86_CENTAUR_FAM6_NANO,    NULL),
-    X86_MATCH_VENDOR_FAM_MODEL(CENTAUR, 7, X86_MODEL_ANY, NULL),
     {}
 };
 MODULE_DEVICE_TABLE(x86cpu, cputemp_ids);
diff --git a/drivers/hwmon/zhaoxin-cputemp.c b/drivers/hwmon/zhaoxin-cputemp.c
new file mode 100644
index 000000000000..dcedb51515f0
--- /dev/null
+++ b/drivers/hwmon/zhaoxin-cputemp.c
@@ -0,0 +1,292 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * zhaoxin-cputemp.c - Driver for Zhaoxin CPU core temperature monitoring
+ */
+
+#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    "zhaoxin_cputemp"
+
+enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME };
+
+/* Functions declaration */
+
+struct zhaoxin_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 zhaoxin_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 zhaoxin_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 zhaoxin_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 *zhaoxin_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 zhaoxin_cputemp_group = {
+    .attrs = zhaoxin_cputemp_attributes,
+};
+
+/* Optional attributes */
+static DEVICE_ATTR_RO(cpu0_vid);
+
+static int zhaoxin_cputemp_probe(struct platform_device *pdev)
+{
+    struct zhaoxin_cputemp_data *data;
+    int err;
+    u32 eax, edx;
+
+    data = devm_kzalloc(&pdev->dev, sizeof(struct zhaoxin_cputemp_data), GFP_KERNEL);
+    if (!data)
+        return -ENOMEM;
+
+    data->id = pdev->id;
+    data->name = "zhaoxin_cputemp";
+    data->msr_temp = 0x1423;
+
+    /* 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, &zhaoxin_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, &zhaoxin_cputemp_group);
+    return err;
+}
+
+static int zhaoxin_cputemp_remove(struct platform_device *pdev)
+{
+    struct zhaoxin_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, &zhaoxin_cputemp_group);
+    return 0;
+}
+
+static struct platform_driver zhaoxin_cputemp_driver = {
+    .driver = {
+        .name = DRVNAME,
+    },
+    .probe = zhaoxin_cputemp_probe,
+    .remove = zhaoxin_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 zhaoxin_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 zhaoxin_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_MATCH_VENDOR_FAM_MODEL(CENTAUR, 7, X86_MODEL_ANY, NULL),
+    X86_MATCH_VENDOR_FAM_MODEL(ZHAOXIN, 7, X86_MODEL_ANY, NULL),
+    {}
+};
+MODULE_DEVICE_TABLE(x86cpu, cputemp_ids);
+
+static enum cpuhp_state zhaoxin_temp_online;
+
+static int __init zhaoxin_cputemp_init(void)
+{
+    int err;
+
+    if (!x86_match_cpu(cputemp_ids))
+        return -ENODEV;
+
+    err = platform_driver_register(&zhaoxin_cputemp_driver);
+    if (err)
+        goto exit;
+
+    err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hwmon/zhaoxin:online",
+                zhaoxin_cputemp_online, zhaoxin_cputemp_down_prep);
+    if (err < 0)
+        goto exit_driver_unreg;
+    zhaoxin_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(zhaoxin_temp_online);
+#endif
+exit_driver_unreg:
+    platform_driver_unregister(&zhaoxin_cputemp_driver);
+exit:
+    return err;
+}
+
+static void __exit zhaoxin_cputemp_exit(void)
+{
+    cpuhp_remove_state(zhaoxin_temp_online);
+    platform_driver_unregister(&zhaoxin_cputemp_driver);
+}
+
+MODULE_DESCRIPTION("Zhaoxin CPU temperature monitor");
+MODULE_LICENSE("GPL");
+
+module_init(zhaoxin_cputemp_init)
+module_exit(zhaoxin_cputemp_exit)
-- 
2.20.1