From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754696Ab1DEUNf (ORCPT ); Tue, 5 Apr 2011 16:13:35 -0400 Received: from imr4.ericy.com ([198.24.6.8]:32903 "EHLO imr4.ericy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753739Ab1DEUNe (ORCPT ); Tue, 5 Apr 2011 16:13:34 -0400 Date: Tue, 5 Apr 2011 13:12:38 -0700 From: Guenter Roeck To: Andreas Herrmann CC: Jean Delvare , Thomas Renninger , "lm-sensors@lm-sensors.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2] hwmon: Add driver for AMD family 15h processor power information Message-ID: <20110405201238.GA20551@ericsson.com> References: <20110404160733.GA11818@alberich.amd.com> <20110405144536.GA5054@alberich.amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20110405144536.GA5054@alberich.amd.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 05, 2011 at 10:45:36AM -0400, Andreas Herrmann wrote: > From: Andreas Herrmann > > 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_cap (ProcessorPwrWatts) Hi Andreas, What does the CPU do if ProcessorPwrWatts is reached ? Does it start to limit power consumption, ie does it enforce the limit ? If not you might want to use power1_max instead. > * power1_input (CurrPwrWatts) > > Changes from v1:: > - removed deprecated code line, > - fixed comment, > - report power only once per socket (Power information is provided > for the entire package. On multi-node processors it should only be > reported on internal node 0.) > > Signed-off-by: Andreas Herrmann > --- > drivers/hwmon/Kconfig | 10 ++ > drivers/hwmon/Makefile | 1 + > drivers/hwmon/f15h_power.c | 216 ++++++++++++++++++++++++++++++++++++++++++++ Please also add Documentation/hwmon/f15h_power. > 3 files changed, 227 insertions(+), 0 deletions(-) > create mode 100644 drivers/hwmon/f15h_power.c > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 8e84b31..0268623 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_F15H_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 f15hpower. f15h_power > + > config SENSORS_ASB100 > tristate "Asus ASB100 Bach" > depends on X86 && I2C && EXPERIMENTAL > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index dde02d9..e554b88 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -62,6 +62,7 @@ obj-$(CONFIG_SENSORS_JC42) += jc42.o > obj-$(CONFIG_SENSORS_JZ4740) += jz4740-hwmon.o > obj-$(CONFIG_SENSORS_K8TEMP) += k8temp.o > obj-$(CONFIG_SENSORS_K10TEMP) += k10temp.o > +obj-$(CONFIG_SENSORS_F15H_POWER) += f15h_power.o > obj-$(CONFIG_SENSORS_LIS3LV02D) += lis3lv02d.o hp_accel.o > obj-$(CONFIG_SENSORS_LIS3_SPI) += lis3lv02d.o lis3lv02d_spi.o > obj-$(CONFIG_SENSORS_LIS3_I2C) += lis3lv02d.o lis3lv02d_i2c.o > diff --git a/drivers/hwmon/f15h_power.c b/drivers/hwmon/f15h_power.c > new file mode 100644 > index 0000000..40e3cbd > --- /dev/null > +++ b/drivers/hwmon/f15h_power.c > @@ -0,0 +1,216 @@ > +/* > + * f15h_power.c - AMD Family 15h processor power monitoring > + * > + * Copyright (c) 2011 Advanced Micro Devices, Inc. > + * Author: Andreas Herrmann > + * > + * > + * 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 . > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor"); > +MODULE_AUTHOR("Andreas Herrmann "); > +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 > + > +static ssize_t show_power(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + u32 val, btdp, tdpl, tdp2w, arange; > + s32 acap; > + u64 ctdp; > + struct pci_dev *f4 = to_pci_dev(dev); > + struct pci_dev *f5; > + > + pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val); > + btdp = (val >> 16) & 0xffff; > + > + f5 = pci_get_slot(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5)); > + if (!f5) { > + dev_err(dev, "no function 5 available on this slot\n"); > + return 0; > + } Unless this is a temporary error condition, you should check if this function exists in the probe function, and not create a sysfs entry if it doesn't. If it is a temporary error which needs a runtime check, you should return a negative value to indicate that there was an error. > + > + pci_read_config_dword(f5, REG_TDP_RUNNING_AVERAGE, &val); > + acap = (val >> 4) & 0x3fffff; > + acap = sign_extend32(acap, 22); > + arange = val & 0xf; > + > + pci_read_config_dword(f5, REG_TDP_LIMIT3, &val); > + pci_dev_put(f5); > + > + tdpl = (val >> 16) & 0x1fff; > + tdp2w = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f); > + ctdp = tdpl - (s32)(acap >> (arange + 1)) + btdp; > + ctdp *= tdp2w; > + > + /* > + * 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) > + */ > + ctdp = (ctdp * 15625) >> 10; > + return sprintf(buf, "%d\n", (u32) ctdp); %u > +} > +static DEVICE_ATTR(power1_input, S_IRUGO, show_power, NULL); > + > +static ssize_t show_power_cap(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + u32 val, tdp2w; > + u64 ptdp; > + struct pci_dev *f4 = to_pci_dev(dev); > + struct pci_dev *f5; > + > + pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val); > + ptdp = val & 0xffff; > + > + f5 = pci_get_slot(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5)); > + if (!f5) { > + dev_err(dev, "no function 5 available on this slot\n"); > + return 0; > + } > + Same as above - should be checked in probe function. If it is a temporary error which needs a runtime check, you should return a negative value to indicate that there was an error. > + pci_read_config_dword(f5, REG_TDP_LIMIT3, &val); > + pci_dev_put(f5); > + > + tdp2w = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f); > + ptdp *= tdp2w; > + > + /* result not allowed to be >= 256W */ > + WARN_ON(ptdp>>16 >= 256); > + Does this really ask for such drastic measures, or would dev_warn() be sufficient ? > + /* convert to microWatt */ > + ptdp = (ptdp * 15625) >> 10; > + return sprintf(buf, "%d\n", (u32) ptdp); %u > +} > +static DEVICE_ATTR(power1_cap, S_IRUGO, show_power_cap, NULL); > + > +static ssize_t show_name(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + return sprintf(buf, "f15h_power\n"); > +} > +static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); > + > +static int __devinit f15h_power_is_internal_node0(struct pci_dev *f4) > +{ > + u32 val; > + struct pci_dev *f3; > + > + f3 = pci_get_slot(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3)); > + if (!f3) { > + dev_err(&f4->dev, "no function 3 available on this slot\n"); > + return 0; It is a common practice to return a negative value on errors. Why not here ? Also, is this really an error which asks for an error message, or just a CPU or system which does not support the attribute ? In the latter case, you should not display an error message. > + } > + > + pci_read_config_dword(f3, REG_NORTHBRIDGE_CAP, &val); > + pci_dev_put(f3); > + > + if ((val & BIT(29)) && ((val >> 30) & 3)) > + return 0; > + > + return 1; > +} > + > +static int __devinit f15h_power_probe(struct pci_dev *pdev, > + const struct pci_device_id *id) > +{ > + struct device *hwmon_dev; > + int err = -ENODEV; > + > + if (!f15h_power_is_internal_node0(pdev)) > + goto exit; > + > + err = device_create_file(&pdev->dev, &dev_attr_power1_input); > + if (err) > + goto exit; > + err = device_create_file(&pdev->dev, &dev_attr_power1_cap); > + if (err) > + goto exit_remove; > + > + err = device_create_file(&pdev->dev, &dev_attr_name); > + if (err) > + goto exit_remove; > + > + hwmon_dev = hwmon_device_register(&pdev->dev); > + if (IS_ERR(hwmon_dev)) { > + err = PTR_ERR(hwmon_dev); > + goto exit_remove; > + } > + dev_set_drvdata(&pdev->dev, hwmon_dev); > + > + return 0; > + > +exit_remove: > + device_remove_file(&pdev->dev, &dev_attr_name); > + device_remove_file(&pdev->dev, &dev_attr_power1_input); > + device_remove_file(&pdev->dev, &dev_attr_power1_cap); > +exit: > + return err; > +} > + > +static void __devexit f15h_power_remove(struct pci_dev *pdev) > +{ > + hwmon_device_unregister(dev_get_drvdata(&pdev->dev)); > + device_remove_file(&pdev->dev, &dev_attr_name); > + device_remove_file(&pdev->dev, &dev_attr_power1_input); > + device_remove_file(&pdev->dev, &dev_attr_power1_cap); > + dev_set_drvdata(&pdev->dev, NULL); > +} > + > +static const struct pci_device_id f15h_power_id_table[] = { checkpatch says: WARNING: Use DEFINE_PCI_DEVICE_TABLE for struct pci_device_id #326: FILE: drivers/hwmon/f15h_power.c:192: Please fix. > + { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_LINK) }, > + {} > +}; > +MODULE_DEVICE_TABLE(pci, f15h_power_id_table); > + > +static struct pci_driver f15h_power_driver = { > + .name = "f15h_power", > + .id_table = f15h_power_id_table, > + .probe = f15h_power_probe, > + .remove = __devexit_p(f15h_power_remove), > +}; > + > +static int __init f15h_power_init(void) > +{ > + return pci_register_driver(&f15h_power_driver); > +} > + > +static void __exit f15h_power_exit(void) > +{ > + pci_unregister_driver(&f15h_power_driver); > +} > + > +module_init(f15h_power_init) > +module_exit(f15h_power_exit) > -- > 1.7.3.1 >