lkml.org 
[lkml]   [2011]   [Apr]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v4] hwmon: Add driver for AMD family 15h processor power information
    Hi Andreas,

    On Fri, 8 Apr 2011 15:54:07 +0200, Andreas Herrmann wrote:
    > From: Andreas Herrmann <andreas.herrmann3@amd.com>
    >
    > This CPU family provides NB register values to gather following
    > TDP information
    >
    > * ProcessorPwrWatts: Specifies in Watts the maximum amount of power
    > the processor can support.
    > * CurrPwrWatts: Specifies in Watts the current amount of power being
    > consumed by the processor.
    >
    > This driver provides
    >
    > * power1_max (ProcessorPwrWatts)

    Still questionable whether power1_crit would be more appropriate...

    > * power1_input (CurrPwrWatts)
    >
    > Changes from v2:
    > - fix format strings
    > - removed paranoid checks for existense of functions 3 and 5
    > - changed return type of function f15h_power_is_internal_node0
    > - use power1_max instead of power1_cap
    > - use dev_warn instead of WARN_ON
    > - rebased against 2.6.39-rc2
    > - added Documentation/hwmon/f15h_power
    >
    > Changes from v3:
    > - read static power information only once (during driver initialization)
    > - made use of attribute groups
    > - renamed f15h_power to fam15h_power
    >
    > Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
    > ---
    > Documentation/hwmon/fam15h_power | 37 ++++++
    > drivers/hwmon/Kconfig | 10 ++
    > drivers/hwmon/Makefile | 1 +
    > drivers/hwmon/fam15h_power.c | 229 ++++++++++++++++++++++++++++++++++++++
    > 4 files changed, 277 insertions(+), 0 deletions(-)
    > create mode 100644 Documentation/hwmon/fam15h_power
    > create mode 100644 drivers/hwmon/fam15h_power.c
    >
    > At this stage I consider the _max attribute as the right one for
    > reporting ProcessorPwrWatts.
    >
    > Hopefully I've addressed all your coments.
    > Please apply.

    It seems I have some more comments, but these are very small things you
    should have no problem addressing quickly:

    > diff --git a/Documentation/hwmon/fam15h_power b/Documentation/hwmon/fam15h_power
    > new file mode 100644
    > index 0000000..2f4d291
    > --- /dev/null
    > +++ b/Documentation/hwmon/fam15h_power
    > @@ -0,0 +1,37 @@
    > +Kernel driver fam15h_power
    > +==========================
    > +
    > +Supported chips:
    > +* AMD Family 15h Processors
    > +
    > + Prefix: 'fam15h_power'
    > + Addresses scanned: PCI space
    > + Datasheets:
    > + BIOS and Kernel Developer's Guide (BKDG) For AMD Family 15h Processors
    > + (not yet published)
    > +
    > +Author: Andreas Herrmann <andreas.herrmann3@amd.com>
    > +
    > +Description
    > +-----------
    > +
    > +This driver permits reading of registers providing power information
    > +of AMD Family 15h processors.
    > +
    > +For AMD Family 15h processors the following power values can be
    > +calculated using different processor northbridge function registers:
    > +
    > +* BasePwrWatts: Specifies in watts the maximum amount of power
    > + consumed by the processor for NB and logic external to the core.
    > +* ProcessorPwrWatts: Specifies in watts the maximum amount of power
    > + the processor can support.
    > +* CurrPwrWatts: Specifies in watts the current amount of power being
    > + consumed by the processor.
    > +
    > +This driver provides ProcessorPwrWatts and CurrPwrWatts:
    > +* power1_max (ProcessorPwrWatts)
    > +* power1_input (CurrPwrWatts)
    > +
    > +On multi-node processors the calculated value is for the entire
    > +package and not for a single node. Thus the driver creates sysfs
    > +attributes only for internal node0 of a multi-node processor.
    > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
    > index 060ef63..fb3e334 100644
    > --- a/drivers/hwmon/Kconfig
    > +++ b/drivers/hwmon/Kconfig
    > @@ -249,6 +249,16 @@ config SENSORS_K10TEMP
    > This driver can also be built as a module. If so, the module
    > will be called k10temp.
    >
    > +config SENSORS_FAM15H_POWER
    > + tristate "AMD Family 15h processor power"
    > + depends on X86 && PCI
    > + help
    > + If you say yes here you get support for processor power
    > + information of your AMD family 15h CPU.
    > +
    > + This driver can also be built as a module. If so, the module
    > + will be called fam15h_power.
    > +
    > config SENSORS_ASB100
    > tristate "Asus ASB100 Bach"
    > depends on X86 && I2C && EXPERIMENTAL
    > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
    > index 967d0ea..236d3f9 100644
    > --- a/drivers/hwmon/Makefile
    > +++ b/drivers/hwmon/Makefile
    > @@ -49,6 +49,7 @@ obj-$(CONFIG_SENSORS_EMC2103) += emc2103.o
    > obj-$(CONFIG_SENSORS_F71805F) += f71805f.o
    > obj-$(CONFIG_SENSORS_F71882FG) += f71882fg.o
    > obj-$(CONFIG_SENSORS_F75375S) += f75375s.o
    > +obj-$(CONFIG_SENSORS_FAM15H_POWER) += fam15h_power.o
    > obj-$(CONFIG_SENSORS_FSCHMD) += fschmd.o
    > obj-$(CONFIG_SENSORS_G760A) += g760a.o
    > obj-$(CONFIG_SENSORS_GL518SM) += gl518sm.o
    > diff --git a/drivers/hwmon/fam15h_power.c b/drivers/hwmon/fam15h_power.c
    > new file mode 100644
    > index 0000000..cb6eb99
    > --- /dev/null
    > +++ b/drivers/hwmon/fam15h_power.c
    > @@ -0,0 +1,229 @@
    > +/*
    > + * 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_watt;
    > + unsigned int base_tdp;
    > + unsigned int processor_pwr_watts;

    watt vs. watts is inconsistent, isn't it?

    > +};
    > +
    > +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 = pci_get_drvdata(f4);

    dev_get_drvdata(dev) would be more efficient.

    > +
    > + 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, 22);
    > + running_avg_range = val & 0xf;
    > +
    > + 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 -

    Doubled space.

    > + (s32)(running_avg_capture >> (running_avg_range + 1));
    > + curr_pwr_watts *= data->tdp_to_watt;
    > +
    > + /*
    > + * 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;
    > + 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_max(struct device *dev,
    > + struct device_attribute *attr, char *buf)
    > +{
    > + struct pci_dev *f4 = to_pci_dev(dev);
    > + struct fam15h_power_data *data = pci_get_drvdata(f4);

    dev_get_drvdata(dev) would be more efficient (you don't even need f4
    then.)

    > + return sprintf(buf, "%u\n", data->processor_pwr_watts);
    > +}
    > +static DEVICE_ATTR(power1_max, S_IRUGO, show_power_max, 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_max.attr,
    > + &dev_attr_name.attr,
    > + NULL
    > +};
    > +
    > +static struct attribute_group fam15h_power_attr_group = {

    Can be made const.

    > + .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;
    > +}
    > +
    > +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_watt = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
    > + tmp *= data->tdp_to_watt;
    > +
    > + /* result not allowed to be >= 256W */
    > + if ((tmp>>16) >= 256)

    Please add spaces around ">>" for consistency.

    > + 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;
    > +
    > + 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;
    > + err = sysfs_create_group(&dev->kobj, &fam15h_power_attr_group);
    > + if (err)
    > + goto exit_free_data;
    > +
    > + data->hwmon_dev = hwmon_device_register(&pdev->dev);
    > + if (IS_ERR(data->hwmon_dev)) {
    > + err = PTR_ERR(data->hwmon_dev);
    > + goto exit_remove_group;
    > + }
    > + pci_set_drvdata(pdev, data);

    This is racy. pci_set_drvdata() should be called before creating the
    sysfs attributes, because the sysfs callbacks need it.

    > +
    > + 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 = pci_get_drvdata(pdev);
    > +
    > + dev = &pdev->dev;
    > + hwmon_device_unregister(data->hwmon_dev);
    > + sysfs_remove_group(&dev->kobj, &fam15h_power_attr_group);
    > + pci_set_drvdata(pdev, 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)

    Thanks,
    --
    Jean Delvare


    \
     
     \ /
      Last update: 2011-04-13 15:09    [W:0.073 / U:1.236 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site