Tjmax value retrieved from MSR_IA32_TEMPERATURE_TARGET can be changed at
runtime when the Intel SST-PP (Intel Speed Select Technology -
Performance Profile) level is changed. As a result, the ttarget value
also becomes dyamic.
Improve the code to always get updated ttarget value.
Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx>
---
drivers/hwmon/coretemp.c | 69 ++++++++++++++++++++++++++++------------
1 file changed, 48 insertions(+), 21 deletions(-)
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 5292f7844860..d6084600862f 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -69,7 +69,6 @@ MODULE_PARM_DESC(tjmax, "TjMax value in degrees Celsius");
*/
struct temp_data {
int temp;
- int ttarget;
int tjmax;
unsigned long last_updated;
unsigned int cpu;
@@ -96,6 +95,7 @@ struct platform_data {
};
static int get_tjmax(struct temp_data *tdata, struct device *dev);
+static int get_ttarget(struct temp_data *tdata, struct device *dev);
/* Keep track of how many zone pointers we allocated in init() */
static int max_zones __read_mostly;
@@ -150,8 +150,17 @@ static ssize_t show_ttarget(struct device *dev,
{
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];
+ int ttarget;
+
+ mutex_lock(&tdata->update_lock);
+ ttarget = get_ttarget(tdata, dev);
+ mutex_unlock(&tdata->update_lock);
- return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);
+ if (ttarget >= 0)
+ return sprintf(buf, "%d\n", ttarget);
+ else
+ return ttarget;
}
static ssize_t show_temp(struct device *dev,
@@ -393,6 +402,38 @@ static int get_tjmax(struct temp_data *tdata, struct device *dev)
return tdata->tjmax;
}
+static int get_ttarget(struct temp_data *tdata, struct device *dev)
+{
+ u32 eax, edx;
+ struct cpuinfo_x86 *c = &cpu_data(tdata->cpu);
+ int tj_max, ttarget_offset, ret;
+
+ /*
+ * ttarget is valid only if tjmax can be retrieved from
+ * MSR_IA32_TEMPERATURE_TARGET
+ */
+ if (tdata->tjmax)
+ return -ENODEV;
+
+ if (c->x86_model <= 0xe || c->x86_model == 0x1c)
+ return -ENODEV;
+
+ /*
+ * 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.
+ */
+ ret = rdmsr_safe_on_cpu(tdata->cpu, MSR_IA32_TEMPERATURE_TARGET,
+ &eax, &edx);
+ if (ret)
+ return ret;
+
+ tj_max = (eax >> 16) & 0xff;
+ ttarget_offset = (eax >> 8) & 0xff;
+
+ return (tj_max - ttarget_offset) * 1000;
+}
+
static int create_core_attrs(struct temp_data *tdata, struct device *dev,
int attr_no)
{
@@ -468,9 +509,8 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu,
{
struct temp_data *tdata;
struct platform_data *pdata = platform_get_drvdata(pdev);
- struct cpuinfo_x86 *c = &cpu_data(cpu);
u32 eax, edx;
- int err, index, attr_no, tjmax;
+ int err, index, attr_no;
/*
* Find attr number for sysfs:
@@ -504,23 +544,10 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu,
if (err)
goto exit_free;
- /* We can access status register. Get Critical Temperature */
- tjmax = get_tjmax(tdata, &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
- = tjmax - ((eax >> 8) & 0xff) * 1000;
- tdata->attr_size++;
- }
- }
+ /* Make sure tdata->tjmax is a valid indicator for dynamic/static tjmax */
+ get_tjmax(tdata, &pdev->dev);
+ if (get_ttarget(tdata, &pdev->dev) >= 0)
+ tdata->attr_size++;
pdata->core_data[attr_no] = tdata;
--
2.25.1
