drivers/hwmon/fam15h_power.c - kernel/mindspeed - Git at Google

 /*
  * fam15h_power.c - AMD Family 15h processor power monitoring
  *
  * Copyright (c) 2011 Advanced Micro Devices, Inc.
  * Author: Andreas Herrmann <andreas.herrmann3@amd.com>
  *
  *
  * This driver is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This driver is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  * See the GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this driver; if not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/err.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/bitops.h>
 #include <asm/processor.h>

 MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
 MODULE_AUTHOR("Andreas Herrmann <andreas.herrmann3@amd.com>");
 MODULE_LICENSE("GPL");

 /* D18F3 */
 #define REG_NORTHBRIDGE_CAP		0xe8

 /* D18F4 */
 #define REG_PROCESSOR_TDP		0x1b8

 /* D18F5 */
 #define REG_TDP_RUNNING_AVERAGE		0xe0
 #define REG_TDP_LIMIT3			0xe8

 struct fam15h_power_data {
 	struct device *hwmon_dev;
 	unsigned int tdp_to_watts;
 	unsigned int base_tdp;
 	unsigned int processor_pwr_watts;
 };

 static ssize_t show_power(struct device *dev,
 			  struct device_attribute *attr, char *buf)
 {
 	u32 val, tdp_limit, running_avg_range;
 	s32 running_avg_capture;
 	u64 curr_pwr_watts;
 	struct pci_dev *f4 = to_pci_dev(dev);
 	struct fam15h_power_data *data = dev_get_drvdata(dev);

 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
 				  REG_TDP_RUNNING_AVERAGE, &val);
 	running_avg_capture = (val >> 4) & 0x3fffff;
 	running_avg_capture = sign_extend32(running_avg_capture, 21);
 	running_avg_range = (val & 0xf) + 1;

 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
 				  REG_TDP_LIMIT3, &val);

 	tdp_limit = val >> 16;
 	curr_pwr_watts = (tdp_limit + data->base_tdp) << running_avg_range;
 	curr_pwr_watts -= running_avg_capture;
 	curr_pwr_watts *= data->tdp_to_watts;

 	/*
 	 * Convert to microWatt
 	 *
 	 * power is in Watt provided as fixed point integer with
 	 * scaling factor 1/(2^16).  For conversion we use
 	 * (10^6)/(2^16) = 15625/(2^10)
 	 */
 	curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
 	return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
 }
 static DEVICE_ATTR(power1_input, S_IRUGO, show_power, NULL);

 static ssize_t show_power_crit(struct device *dev,
 			       struct device_attribute *attr, char *buf)
 {
 	struct fam15h_power_data *data = dev_get_drvdata(dev);

 	return sprintf(buf, "%u\n", data->processor_pwr_watts);
 }
 static DEVICE_ATTR(power1_crit, S_IRUGO, show_power_crit, NULL);

 static ssize_t show_name(struct device *dev,
 			 struct device_attribute *attr, char *buf)
 {
 	return sprintf(buf, "fam15h_power\n");
 }
 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

 static struct attribute *fam15h_power_attrs[] = {
 	&dev_attr_power1_input.attr,
 	&dev_attr_power1_crit.attr,
 	&dev_attr_name.attr,
 	NULL
 };

 static const struct attribute_group fam15h_power_attr_group = {
 	.attrs	= fam15h_power_attrs,
 };

 static bool __devinit fam15h_power_is_internal_node0(struct pci_dev *f4)
 {
 	u32 val;

 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
 				  REG_NORTHBRIDGE_CAP, &val);
 	if ((val & BIT(29)) && ((val >> 30) & 3))
 		return false;

 	return true;
 }

 /*
  * Newer BKDG versions have an updated recommendation on how to properly
  * initialize the running average range (was: 0xE, now: 0x9). This avoids
  * counter saturations resulting in bogus power readings.
  * We correct this value ourselves to cope with older BIOSes.
  */
 static DEFINE_PCI_DEVICE_TABLE(affected_device) = {
 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
 	{ 0 }
 };

 static void __devinit tweak_runavg_range(struct pci_dev *pdev)
 {
 	u32 val;

 	/*
 	 * let this quirk apply only to the current version of the
 	 * northbridge, since future versions may change the behavior
 	 */
 	if (!pci_match_id(affected_device, pdev))
 		return;

 	pci_bus_read_config_dword(pdev->bus,
 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
 		REG_TDP_RUNNING_AVERAGE, &val);
 	if ((val & 0xf) != 0xe)
 		return;

 	val &= ~0xf;
 	val |=  0x9;
 	pci_bus_write_config_dword(pdev->bus,
 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
 		REG_TDP_RUNNING_AVERAGE, val);
 }

 static void __devinit fam15h_power_init_data(struct pci_dev *f4,
 					     struct fam15h_power_data *data)
 {
 	u32 val;
 	u64 tmp;

 	pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
 	data->base_tdp = val >> 16;
 	tmp = val & 0xffff;

 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
 				  REG_TDP_LIMIT3, &val);

 	data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
 	tmp *= data->tdp_to_watts;

 	/* result not allowed to be >= 256W */
 	if ((tmp >> 16) >= 256)
 		dev_warn(&f4->dev, "Bogus value for ProcessorPwrWatts "
 			 "(processor_pwr_watts>=%u)\n",
 			 (unsigned int) (tmp >> 16));

 	/* convert to microWatt */
 	data->processor_pwr_watts = (tmp * 15625) >> 10;
 }

 static int __devinit fam15h_power_probe(struct pci_dev *pdev,
 					const struct pci_device_id *id)
 {
 	struct fam15h_power_data *data;
 	struct device *dev;
 	int err;

 	/*
 	 * though we ignore every other northbridge, we still have to
 	 * do the tweaking on _each_ node in MCM processors as the counters
 	 * are working hand-in-hand
 	 */
 	tweak_runavg_range(pdev);

 	if (!fam15h_power_is_internal_node0(pdev)) {
 		err = -ENODEV;
 		goto exit;
 	}

 	data = kzalloc(sizeof(struct fam15h_power_data), GFP_KERNEL);
 	if (!data) {
 		err = -ENOMEM;
 		goto exit;
 	}
 	fam15h_power_init_data(pdev, data);
 	dev = &pdev->dev;

 	dev_set_drvdata(dev, data);
 	err = sysfs_create_group(&dev->kobj, &fam15h_power_attr_group);
 	if (err)
 		goto exit_free_data;

 	data->hwmon_dev = hwmon_device_register(dev);
 	if (IS_ERR(data->hwmon_dev)) {
 		err = PTR_ERR(data->hwmon_dev);
 		goto exit_remove_group;
 	}

 	return 0;

 exit_remove_group:
 	sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
 exit_free_data:
 	kfree(data);
 exit:
 	return err;
 }

 static void __devexit fam15h_power_remove(struct pci_dev *pdev)
 {
 	struct device *dev;
 	struct fam15h_power_data *data;

 	dev = &pdev->dev;
 	data = dev_get_drvdata(dev);
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
 	dev_set_drvdata(dev, NULL);
 	kfree(data);
 }

 static DEFINE_PCI_DEVICE_TABLE(fam15h_power_id_table) = {
 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
 	{}
 };
 MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);

 static struct pci_driver fam15h_power_driver = {
 	.name = "fam15h_power",
 	.id_table = fam15h_power_id_table,
 	.probe = fam15h_power_probe,
 	.remove = __devexit_p(fam15h_power_remove),
 };

 static int __init fam15h_power_init(void)
 {
 	return pci_register_driver(&fam15h_power_driver);
 }

 static void __exit fam15h_power_exit(void)
 {
 	pci_unregister_driver(&fam15h_power_driver);
 }

 module_init(fam15h_power_init)
 module_exit(fam15h_power_exit)
	/*
	* fam15h_power.c - AMD Family 15h processor power monitoring
	*
	* Copyright (c) 2011 Advanced Micro Devices, Inc.
	* Author: Andreas Herrmann <andreas.herrmann3@amd.com>
	*
	*
	* This driver is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This driver is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	* See the GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this driver; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/err.h>
	#include <linux/hwmon.h>
	#include <linux/hwmon-sysfs.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/bitops.h>
	#include <asm/processor.h>

	MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
	MODULE_AUTHOR("Andreas Herrmann <andreas.herrmann3@amd.com>");
	MODULE_LICENSE("GPL");

	/* D18F3 */
	#define REG_NORTHBRIDGE_CAP 0xe8

	/* D18F4 */
	#define REG_PROCESSOR_TDP 0x1b8

	/* D18F5 */
	#define REG_TDP_RUNNING_AVERAGE 0xe0
	#define REG_TDP_LIMIT3 0xe8

	struct fam15h_power_data {
	struct device *hwmon_dev;
	unsigned int tdp_to_watts;
	unsigned int base_tdp;
	unsigned int processor_pwr_watts;
	};

	static ssize_t show_power(struct device *dev,
	struct device_attribute attr, char buf)
	{
	u32 val, tdp_limit, running_avg_range;
	s32 running_avg_capture;
	u64 curr_pwr_watts;
	struct pci_dev *f4 = to_pci_dev(dev);
	struct fam15h_power_data *data = dev_get_drvdata(dev);

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
	REG_TDP_RUNNING_AVERAGE, &val);
	running_avg_capture = (val >> 4) & 0x3fffff;
	running_avg_capture = sign_extend32(running_avg_capture, 21);
	running_avg_range = (val & 0xf) + 1;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
	REG_TDP_LIMIT3, &val);

	tdp_limit = val >> 16;
	curr_pwr_watts = (tdp_limit + data->base_tdp) << running_avg_range;
	curr_pwr_watts -= running_avg_capture;
	curr_pwr_watts *= data->tdp_to_watts;

	/*
	* Convert to microWatt
	*
	* power is in Watt provided as fixed point integer with
	* scaling factor 1/(2^16). For conversion we use
	* (10^6)/(2^16) = 15625/(2^10)
	*/
	curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
	return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
	}
	static DEVICE_ATTR(power1_input, S_IRUGO, show_power, NULL);

	static ssize_t show_power_crit(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct fam15h_power_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%u\n", data->processor_pwr_watts);
	}
	static DEVICE_ATTR(power1_crit, S_IRUGO, show_power_crit, NULL);

	static ssize_t show_name(struct device *dev,
	struct device_attribute attr, char buf)
	{
	return sprintf(buf, "fam15h_power\n");
	}
	static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

	static struct attribute *fam15h_power_attrs[] = {
	&dev_attr_power1_input.attr,
	&dev_attr_power1_crit.attr,
	&dev_attr_name.attr,
	NULL
	};

	static const struct attribute_group fam15h_power_attr_group = {
	.attrs = fam15h_power_attrs,
	};

	static bool __devinit fam15h_power_is_internal_node0(struct pci_dev *f4)
	{
	u32 val;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
	REG_NORTHBRIDGE_CAP, &val);
	if ((val & BIT(29)) && ((val >> 30) & 3))
	return false;

	return true;
	}

	/*
	* Newer BKDG versions have an updated recommendation on how to properly
	* initialize the running average range (was: 0xE, now: 0x9). This avoids
	* counter saturations resulting in bogus power readings.
	* We correct this value ourselves to cope with older BIOSes.
	*/
	static DEFINE_PCI_DEVICE_TABLE(affected_device) = {
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
	{ 0 }
	};

	static void __devinit tweak_runavg_range(struct pci_dev *pdev)
	{
	u32 val;

	/*
	* let this quirk apply only to the current version of the
	* northbridge, since future versions may change the behavior
	*/
	if (!pci_match_id(affected_device, pdev))
	return;

	pci_bus_read_config_dword(pdev->bus,
	PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
	REG_TDP_RUNNING_AVERAGE, &val);
	if ((val & 0xf) != 0xe)
	return;

	val &= ~0xf;
	val \|= 0x9;
	pci_bus_write_config_dword(pdev->bus,
	PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
	REG_TDP_RUNNING_AVERAGE, val);
	}

	static void __devinit fam15h_power_init_data(struct pci_dev *f4,
	struct fam15h_power_data *data)
	{
	u32 val;
	u64 tmp;

	pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
	data->base_tdp = val >> 16;
	tmp = val & 0xffff;

	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
	REG_TDP_LIMIT3, &val);

	data->tdp_to_watts = ((val & 0x3ff) << 6) \| ((val >> 10) & 0x3f);
	tmp *= data->tdp_to_watts;

	/* result not allowed to be >= 256W */
	if ((tmp >> 16) >= 256)
	dev_warn(&f4->dev, "Bogus value for ProcessorPwrWatts "
	"(processor_pwr_watts>=%u)\n",
	(unsigned int) (tmp >> 16));

	/* convert to microWatt */
	data->processor_pwr_watts = (tmp * 15625) >> 10;
	}

	static int __devinit fam15h_power_probe(struct pci_dev *pdev,
	const struct pci_device_id *id)
	{
	struct fam15h_power_data *data;
	struct device *dev;
	int err;

	/*
	* though we ignore every other northbridge, we still have to
	* do the tweaking on _each_ node in MCM processors as the counters
	* are working hand-in-hand
	*/
	tweak_runavg_range(pdev);

	if (!fam15h_power_is_internal_node0(pdev)) {
	err = -ENODEV;
	goto exit;
	}

	data = kzalloc(sizeof(struct fam15h_power_data), GFP_KERNEL);
	if (!data) {
	err = -ENOMEM;
	goto exit;
	}
	fam15h_power_init_data(pdev, data);
	dev = &pdev->dev;

	dev_set_drvdata(dev, data);
	err = sysfs_create_group(&dev->kobj, &fam15h_power_attr_group);
	if (err)
	goto exit_free_data;

	data->hwmon_dev = hwmon_device_register(dev);
	if (IS_ERR(data->hwmon_dev)) {
	err = PTR_ERR(data->hwmon_dev);
	goto exit_remove_group;
	}

	return 0;

	exit_remove_group:
	sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
	exit_free_data:
	kfree(data);
	exit:
	return err;
	}

	static void __devexit fam15h_power_remove(struct pci_dev *pdev)
	{
	struct device *dev;
	struct fam15h_power_data *data;

	dev = &pdev->dev;
	data = dev_get_drvdata(dev);
	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
	dev_set_drvdata(dev, NULL);
	kfree(data);
	}

	static DEFINE_PCI_DEVICE_TABLE(fam15h_power_id_table) = {
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
	{}
	};
	MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);

	static struct pci_driver fam15h_power_driver = {
	.name = "fam15h_power",
	.id_table = fam15h_power_id_table,
	.probe = fam15h_power_probe,
	.remove = __devexit_p(fam15h_power_remove),
	};

	static int __init fam15h_power_init(void)
	{
	return pci_register_driver(&fam15h_power_driver);
	}

	static void __exit fam15h_power_exit(void)
	{
	pci_unregister_driver(&fam15h_power_driver);
	}

	module_init(fam15h_power_init)
	module_exit(fam15h_power_exit)