Patch[2/2]:hwmon:Adding_Threshold_Support_to_Coretemp.c

From: R, Durgadoss
Date: Mon Dec 20 2010 - 01:11:34 EST


Hi,

I am submitting a patch to enable core thermal threshold
Support to coretemp.c. There are two core thermal thresholds
available through sysfs interfaces temp1_max and temp1_max_hyst.
The temp1_max_alarm is set when temperature reaches or crosses
above temp1_max or drops below temp1_max_hyst.

This patch is generated against stable Linux-2.6 kernel.

Kindly review and merge.
----------------------------------------------------------------
From: Durgadoss R <durgadoss.r@xxxxxxxxx>

Date: Sun, 19 Dec 2010 22:44:54 +0530
Subject: [PATCH 2/2] hwmon:Adding_Threshold_Support_to_Coretemp

This patch adds core thermal thresholds support to coretemp.
These thresholds can be configured via the sysfs interfaces temp1_max
and temp1_max_hyst. An interrupt is generated when CPU temperature
goes above temp1_max or drops below temp1_max_hyst.

Signed-off-by: Durgadoss R <durgadoss.r@xxxxxxxxx>

---
Documentation/hwmon/coretemp | 8 ++
drivers/hwmon/coretemp.c | 214 ++++++++++++++++++++++++++++++++++++++----
2 files changed, 202 insertions(+), 20 deletions(-)

diff --git a/Documentation/hwmon/coretemp b/Documentation/hwmon/coretemp
index 25568f8..615fdbe 100644
--- a/Documentation/hwmon/coretemp
+++ b/Documentation/hwmon/coretemp
@@ -29,6 +29,14 @@ the Out-Of-Spec bit. Following table summarizes the exported sysfs files:

temp1_input - Core temperature (in millidegrees Celsius).
temp1_max - All cooling devices should be turned on (on Core2).
+ Initialized with IA32_TEMPERATURE_TARGET if supported,
+ otherwise initialized with (tjmax - 20). When the CPU
+ temperature reaches this temperature, an interrupt is
+ generated and temp1_max_alarm is set.
+temp1_max_hyst - If the CPU temperature falls below than temperature,
+ an interrupt is generated and temp1_max_alarm is reset.
+temp1_max_alarm - Set if the temperature reaches or exceeds temp1_max.
+ Reset if the temperature drops to or below temp1_max_hyst.
temp1_crit - Maximum junction temperature (in millidegrees Celsius).
temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
Correct CPU operation is no longer guaranteed.
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 42de98d..025902f 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -36,11 +36,12 @@
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/smp.h>
+#include <asm/mce.h>

#define DRVNAME "coretemp"

-typedef enum { SHOW_TEMP, SHOW_TJMAX, SHOW_TTARGET, SHOW_LABEL,
- SHOW_NAME } SHOW;
+enum attributes { SHOW_TEMP, SHOW_TJMAX, CORE_TTARGET, CORE_TMIN, SHOW_LABEL,
+ SHOW_NAME, SHOW_CRIT_ALARM, SHOW_MAX_ALARM } attrs;

/*
* Functions declaration
@@ -59,9 +60,14 @@ struct coretemp_data {
int temp;
int tjmax;
int ttarget;
- u8 alarm;
+ int tmin;
+ u8 max_alarm;
+ u8 crit_alarm;
};

+static void update_alarm(struct coretemp_data *data);
+static int set_core_threshold(struct coretemp_data *data, int temp, int thres);
+
/*
* Sysfs stuff
*/
@@ -83,9 +89,15 @@ static ssize_t show_name(struct device *dev, struct device_attribute
static ssize_t show_alarm(struct device *dev, struct device_attribute
*devattr, char *buf)
{
- struct coretemp_data *data = coretemp_update_device(dev);
- /* read the Out-of-spec log, never clear */
- return sprintf(buf, "%d\n", data->alarm);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct coretemp_data *data = dev_get_drvdata(dev);
+
+ update_alarm(data);
+ if (attr->index == SHOW_CRIT_ALARM)
+ /* read the Out-of-spec log, never clear */
+ return sprintf(buf, "%d\n", data->crit_alarm);
+
+ return sprintf(buf, "%d\n", data->max_alarm);
}

static ssize_t show_temp(struct device *dev,
@@ -93,33 +105,67 @@ static ssize_t show_temp(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct coretemp_data *data = coretemp_update_device(dev);
- int err;
+ int err = -EINVAL;

- if (attr->index == SHOW_TEMP)
+ switch (attr->index) {
+ case SHOW_TEMP:
err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
- else if (attr->index == SHOW_TJMAX)
+ break;
+ case SHOW_TJMAX:
err = sprintf(buf, "%d\n", data->tjmax);
- else
+ break;
+ case CORE_TTARGET:
err = sprintf(buf, "%d\n", data->ttarget);
+ break;
+ case CORE_TMIN:
+ err = sprintf(buf, "%d\n", data->tmin);
+ break;
+ }
+
return err;
}

+
+static ssize_t store_temp(struct device *dev,
+ struct device_attribute *devattr, const char *buf, size_t count)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct coretemp_data *data = dev_get_drvdata(dev);
+ unsigned long val;
+ int err;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ err = set_core_threshold(data, val, attr->index);
+
+ return err ? err : count;
+}
+
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
SHOW_TEMP);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL,
SHOW_TJMAX);
-static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL,
- SHOW_TTARGET);
-static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
+ store_temp, CORE_TTARGET);
+static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, show_temp,
+ store_temp, CORE_TMIN);
+static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
+ SHOW_CRIT_ALARM);
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
+ SHOW_MAX_ALARM);
static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);

static struct attribute *coretemp_attributes[] = {
&sensor_dev_attr_name.dev_attr.attr,
&sensor_dev_attr_temp1_label.dev_attr.attr,
- &dev_attr_temp1_crit_alarm.attr,
+ &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_crit.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
NULL
};

@@ -127,6 +173,26 @@ static const struct attribute_group coretemp_group = {
.attrs = coretemp_attributes,
};

+static void update_alarm(struct coretemp_data *data)
+{
+ u32 eax, edx;
+
+ rdmsr_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
+
+ /* Update the critical temperature alarm */
+ data->crit_alarm = (eax >> 5) & 1;
+
+ /* Temperature reached threshold1 */
+ if (eax & THERM_LOG_THRESHOLD1)
+ data->max_alarm = 1;
+ /* Temperature reached threshold0 */
+ else if (eax & THERM_LOG_THRESHOLD0)
+ data->max_alarm = 0;
+ /* If none of these cases, don't update max_alarm */
+
+ return;
+}
+
static struct coretemp_data *coretemp_update_device(struct device *dev)
{
struct coretemp_data *data = dev_get_drvdata(dev);
@@ -138,7 +204,6 @@ static struct coretemp_data *coretemp_update_device(struct device *dev)

data->valid = 0;
rdmsr_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
- data->alarm = (eax >> 5) & 1;
/* update only if data has been valid */
if (eax & 0x80000000) {
data->temp = data->tjmax - (((eax >> 16)
@@ -298,6 +363,106 @@ static void __devinit get_ucode_rev_on_cpu(void *edx)
rdmsr(MSR_IA32_UCODE_REV, eax, *(u32 *)edx);
}

+/* Platform thermal Interrupt Handler */
+static int coretemp_interrupt(__u64 msr_val)
+{
+
+ if (msr_val & THERM_LOG_THRESHOLD0) {
+ if (!(msr_val & THERM_STATUS_THRESHOLD0))
+ pr_info("%s:Lower Threshold Reached\n", __func__);
+ /* Reset the Threshold0 interrupt */
+ wrmsrl(MSR_IA32_THERM_STATUS, msr_val & ~THERM_LOG_THRESHOLD0);
+ }
+
+ if (msr_val & THERM_LOG_THRESHOLD1) {
+ if (msr_val & THERM_STATUS_THRESHOLD1)
+ pr_info("%s:Upper Threshold Reached\n", __func__);
+ /* Reset the Threshold1 interrupt */
+ wrmsrl(MSR_IA32_THERM_STATUS, msr_val & ~THERM_LOG_THRESHOLD1);
+ }
+
+ return 0;
+}
+
+static void configure_apic(void *info)
+{
+ u32 l;
+ int *flag = (int *)info;
+
+ l = apic_read(APIC_LVTTHMR);
+
+ if (*flag) /* Non-Zero flag Masks the APIC */
+ apic_write(APIC_LVTTHMR, l | APIC_LVT_MASKED);
+ else /* Zero flag UnMasks the APIC */
+ apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
+}
+
+static int set_core_threshold(struct coretemp_data *data, int temp, int thres)
+{
+ u32 eax, edx;
+ int diff;
+ int flag = 1;
+
+ if (temp > data->tjmax)
+ return -EINVAL;
+
+ mutex_lock(&data->update_lock);
+
+ diff = (data->tjmax - temp)/1000;
+
+ /* Mask the APIC */
+ smp_call_function_single(data->id, &configure_apic, &flag, 1);
+
+ rdmsr_on_cpu(data->id, MSR_IA32_THERM_INTERRUPT, &eax, &edx);
+
+ if (thres == CORE_TMIN) {
+ eax = (eax & ~THERM_MASK_THRESHOLD0) |
+ (diff << THERM_SHIFT_THRESHOLD0);
+ data->tmin = temp;
+ } else {
+ eax = (eax & ~THERM_MASK_THRESHOLD1) |
+ (diff << THERM_SHIFT_THRESHOLD1);
+ data->ttarget = temp;
+ }
+
+ wrmsr_on_cpu(data->id, MSR_IA32_THERM_INTERRUPT, eax, edx);
+
+ /* Unmask the APIC */
+ flag = 0;
+ smp_call_function_single(data->id, &configure_apic, &flag, 1);
+
+ mutex_unlock(&data->update_lock);
+ return 0;
+}
+
+static int __devinit config_thresh_intrpt(struct coretemp_data *data,
+ int enable)
+{
+ u32 eax, edx;
+ int flag = 1; /* Non-Zero Flag masks the apic */
+
+ smp_call_function_single(data->id, &configure_apic, &flag, 1);
+
+ rdmsr_on_cpu(data->id, MSR_IA32_THERM_INTERRUPT, &eax, &edx);
+
+ if (enable) {
+ eax |= (THERM_INT_THRESHOLD0_ENABLE |
+ THERM_INT_THRESHOLD1_ENABLE);
+ platform_thermal_notify = coretemp_interrupt;
+ } else {
+ eax &= (~(THERM_INT_THRESHOLD0_ENABLE |
+ THERM_INT_THRESHOLD1_ENABLE));
+ platform_thermal_notify = NULL;
+ }
+
+ wrmsr_on_cpu(data->id, MSR_IA32_THERM_INTERRUPT, eax, edx);
+
+ flag = 0; /*Flag should be zero to unmask the apic */
+ smp_call_function_single(data->id, &configure_apic, &flag, 1);
+
+ return 0;
+}
+
static int __devinit coretemp_probe(struct platform_device *pdev)
{
struct coretemp_data *data;
@@ -351,6 +516,10 @@ static int __devinit coretemp_probe(struct platform_device *pdev)
}

data->tjmax = get_tjmax(c, data->id, &pdev->dev);
+ /* Initialize ttarget value. If IA32_TEMPERATURE_TARGET is
+ * supported, this value will be over written below
+ */
+ data->ttarget = data->tjmax - 20000;
platform_set_drvdata(pdev, data);

/*
@@ -368,13 +537,18 @@ static int __devinit coretemp_probe(struct platform_device *pdev)
} else {
data->ttarget = data->tjmax -
(((eax >> 8) & 0xff) * 1000);
- err = device_create_file(&pdev->dev,
- &sensor_dev_attr_temp1_max.dev_attr);
- if (err)
- goto exit_free;
}
}

+ /* Enable threshold interrupt support */
+ config_thresh_intrpt(data, 1);
+
+ /* Set Initial Core thresholds.
+ * The lower and upper threshold values here are assumed
+ */
+ set_core_threshold(data, 0, CORE_TMIN);
+ set_core_threshold(data, data->ttarget, CORE_TTARGET);
+
if ((err = sysfs_create_group(&pdev->dev.kobj, &coretemp_group)))
goto exit_dev;

@@ -404,7 +578,7 @@ static int __devexit coretemp_remove(struct platform_device *pdev)

hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&pdev->dev.kobj, &coretemp_group);
- device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
+ config_thresh_intrpt(data, 0);
platform_set_drvdata(pdev, NULL);
kfree(data);
return 0;
--
1.6.5.2

Attachment: 0002-hwmon-Adding_Threshold_Support_to_Coretemp.patch
Description: 0002-hwmon-Adding_Threshold_Support_to_Coretemp.patch