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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/hwmon/fam15h_power.c
Initial import
Diffstat (limited to 'drivers/hwmon/fam15h_power.c')
-rw-r--r--drivers/hwmon/fam15h_power.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/hwmon/fam15h_power.c b/drivers/hwmon/fam15h_power.c
new file mode 100644
index 000000000..3057dfc7e
--- /dev/null
+++ b/drivers/hwmon/fam15h_power.c
@@ -0,0 +1,249 @@
+/*
+ * fam15h_power.c - AMD Family 15h processor power monitoring
+ *
+ * Copyright (c) 2011 Advanced Micro Devices, Inc.
+ * Author: Andreas Herrmann <herrmann.der.user@googlemail.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 <herrmann.der.user@googlemail.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 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 umode_t fam15h_power_is_visible(struct kobject *kobj,
+ struct attribute *attr,
+ int index)
+{
+ /* power1_input is only reported for Fam15h, Models 00h-0fh */
+ if (attr == &dev_attr_power1_input.attr &&
+ (boot_cpu_data.x86 != 0x15 || boot_cpu_data.x86_model > 0xf))
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute *fam15h_power_attrs[] = {
+ &dev_attr_power1_input.attr,
+ &dev_attr_power1_crit.attr,
+ NULL
+};
+
+static const struct attribute_group fam15h_power_group = {
+ .attrs = fam15h_power_attrs,
+ .is_visible = fam15h_power_is_visible,
+};
+__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_15H_M30H_NB_F4) },
+ { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
+ { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_M30H_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);