Commit fae30e3c authored by Zhang Rui's avatar Zhang Rui Committed by Guenter Roeck
Browse files

hwmon: (coretemp) Add support for dynamic ttarget 



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: default avatarZhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20221113153145.32696-4-rui.zhang@intel.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent c0c67f87

drivers/hwmon/coretemp.c

+41 −16
Original line number Diff line number Diff line
@@ -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;
@@ -306,6 +305,30 @@ 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;

	int tjmax, ttarget_offset, ret;



	/*

	 * ttarget is valid only if tjmax can be retrieved from

	 * MSR_IA32_TEMPERATURE_TARGET

	 */

	if (tdata->tjmax)

		return -ENODEV;



	ret = rdmsr_safe_on_cpu(tdata->cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);

	if (ret)

		return ret;



	tjmax = (eax >> 16) & 0xff;



	/* Read the still undocumented bits 8:15 of IA32_TEMPERATURE_TARGET. */

	ttarget_offset = (eax >> 8) & 0xff;



	return (tjmax - ttarget_offset) * 1000;

}



/* 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 */
@@ -359,8 +382,16 @@ 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;



	return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);

	mutex_lock(&tdata->update_lock);

	ttarget = get_ttarget(tdata, dev);

	mutex_unlock(&tdata->update_lock);



	if (ttarget < 0)

		return ttarget;

	return sprintf(buf, "%d\n", ttarget);

}



static ssize_t show_temp(struct device *dev,
@@ -469,7 +500,7 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu, 
	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:
@@ -503,23 +534,17 @@ 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);

	/* Make sure tdata->tjmax is a valid indicator for dynamic/static 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.

	 * The target temperature is available on older CPUs but not in the

	 * MSR_IA32_TEMPERATURE_TARGET 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;

	if (c->x86_model > 0xe && c->x86_model != 0x1c)

		if (get_ttarget(tdata, &pdev->dev) >= 0)

			tdata->attr_size++;

		}

	}



	pdata->core_data[attr_no] = tdata;