/* * fam15h_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"); /* Family 16h Northbridge's function 4 PCI ID */ #define PCI_DEVICE_ID_AMD_16H_NB_F4 0x1534 /* 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 pci_dev *pdev; 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 fam15h_power_data *data = dev_get_drvdata(dev); struct pci_dev *f4 = data->pdev; 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 = ((u64)(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 struct attribute *fam15h_power_attrs[] = { &dev_attr_power1_input.attr, &dev_attr_power1_crit.attr, NULL }; ATTRIBUTE_GROUPS(fam15h_power); static bool 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 const struct pci_device_id affected_device[] = { { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) }, { 0 } }; static void 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); } #ifdef CONFIG_PM static int fam15h_power_resume(struct pci_dev *pdev) { tweak_runavg_range(pdev); return 0; } #else #define fam15h_power_resume NULL #endif static void 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 fam15h_power_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct fam15h_power_data *data; struct device *dev = &pdev->dev; struct device *hwmon_dev; /* * 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)) return -ENODEV; data = devm_kzalloc(dev, sizeof(struct fam15h_power_data), GFP_KERNEL); if (!data) return -ENOMEM; fam15h_power_init_data(pdev, data); data->pdev = pdev; hwmon_dev = devm_hwmon_device_register_with_groups(dev, "fam15h_power", data, fam15h_power_groups); return PTR_ERR_OR_ZERO(hwmon_dev); } static const struct pci_device_id fam15h_power_id_table[] = { { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) }, { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_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, .resume = fam15h_power_resume, }; module_pci_driver(fam15h_power_driver);