This patch adds hwmon based amd_energy driver support for
family 17h processors from AMD.
The driver provides following interface to the userspace
1. Reports the per core consumption
* file: "energy%d_input", label: "Ecore%03d"
2. Reports per socket energy consumption
* file: "energy%d_input", label: "Esocket%d"
3. To, increase the wrap around time of the socket energy
counters, a 64bit accumultor is implemented.
4. Reports scaled energy value in Joules.
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Naveen Krishna Chatradhi <nchatrad@xxxxxxx>
---
Changes in v5:
1. To improve wrap around time. A kernel thread is implemented
to accumulate the socket energy counters into a 64bit.
2. Address other comments from Guenter.
drivers/hwmon/Kconfig | 10 ++
drivers/hwmon/Makefile | 1 +
drivers/hwmon/amd_energy.c | 329 +++++++++++++++++++++++++++++++++++++
3 files changed, 340 insertions(+)
create mode 100644 drivers/hwmon/amd_energy.c
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 4c62f900bf7e..e165e10c49ef 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -324,6 +324,16 @@ config SENSORS_FAM15H_POWER
This driver can also be built as a module. If so, the module
will be called fam15h_power.
+config SENSORS_AMD_ENERGY
+ tristate "AMD RAPL MSR based Energy driver"
+ depends on X86
+ help
+ If you say yes here you get support for core and package energy
+ sensors, based on RAPL MSR for AMD family 17h and above CPUs.
+
+ This driver can also be built as a module. If so, the module
+ will be called as amd_energy.
+
config SENSORS_APPLESMC
tristate "Apple SMC (Motion sensor, light sensor, keyboard backlight)"
depends on INPUT && X86
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index b0b9c8e57176..318f89dc7133 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_SENSORS_ADT7411) += adt7411.o
obj-$(CONFIG_SENSORS_ADT7462) += adt7462.o
obj-$(CONFIG_SENSORS_ADT7470) += adt7470.o
obj-$(CONFIG_SENSORS_ADT7475) += adt7475.o
+obj-$(CONFIG_SENSORS_AMD_ENERGY) += amd_energy.o
obj-$(CONFIG_SENSORS_APPLESMC) += applesmc.o
obj-$(CONFIG_SENSORS_ARM_SCMI) += scmi-hwmon.o
obj-$(CONFIG_SENSORS_ARM_SCPI) += scpi-hwmon.o
diff --git a/drivers/hwmon/amd_energy.c b/drivers/hwmon/amd_energy.c
new file mode 100644
index 000000000000..16364576f067
--- /dev/null
+++ b/drivers/hwmon/amd_energy.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (C) 2020 Advanced Micro Devices, Inc.
+ */
+#include <asm/cpu_device_id.h>
+
+#include <linux/bits.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/device.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/processor.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define DRVNAME "amd_energy"
+
+#define ENERGY_PWR_UNIT_MSR 0xC0010299
+#define ENERGY_CORE_MSR 0xC001029A
+#define ENERGY_PKG_MSR 0xC001029B
+
+#define AMD_ENERGY_UNIT_MASK 0x01F00
+
+struct amd_energy_data {
+ struct hwmon_channel_info energy_info;
+ const struct hwmon_channel_info *info[2];
+ struct hwmon_chip_info chip;
+ /* Lock around the accumulator */
+ struct mutex lock;
+ /* Energy Status Units */
+ u64 energy_units;
+ /* An accumulator for each socket */
+ u64 *energy_ctrs;
+ u64 *prev_value;
+};
+
+/* */
+struct task_struct *wrap_accumulate;
+static int nr_cpus, nr_socks;
+
+static int amd_energy_read_labels(struct device *dev,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel,
+ const char **str)
+{
+ char *buf = devm_kcalloc(dev, 10, sizeof(char), GFP_KERNEL);
+
+ if (channel >= nr_cpus)
+ scnprintf(buf, 9, "Esocket%u", channel - nr_cpus);
+ else
+ scnprintf(buf, 9, "Ecore%03u", channel);
+
+ *str = buf;
+
+ return 0;
+}
+
+static int get_energy_units(struct amd_energy_data *data)
+{
+ u64 rapl_units;
+ int ret;
+
+ ret = rdmsrl_safe(ENERGY_PWR_UNIT_MSR, &rapl_units);
+ if (ret)
+ return ret;
+
+ data->energy_units = (rapl_units & AMD_ENERGY_UNIT_MASK) >> 8;
+ return 0;
+}
+
+static int read_accumulate(struct amd_energy_data *data)
+{
+ int ret, cu;
+ u64 input = 0;
+
+ for (cu = 0; cu < nr_socks; cu++) {
+ int cpu;
+
+ cpu = cpumask_first_and(cpu_online_mask,
+ cpumask_of_node(cu));
+
+ ret = rdmsrl_safe_on_cpu(cpu, ENERGY_PKG_MSR, &input);
+ if (ret)
+ return ret;
+
+ if (input > data->prev_value[cu])
+ data->energy_ctrs[cu] +=
+ input - data->prev_value[cu];
+ else
+ data->energy_ctrs[cu] +=
+ UINT_MAX - data->prev_value[cu] + input;
+
+ data->prev_value[cu] = input;
+ }
+ return 0;
+}
+
+static int amd_energy_read(struct device *dev,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct amd_energy_data *data = dev_get_drvdata(dev);
+ int ret, cpu;
+ u32 reg;
+ u64 input;
+
+ if (channel >= nr_cpus) {
+ reg = ENERGY_PKG_MSR;
+ cpu = cpumask_first_and(cpu_online_mask,
+ cpumask_of_node
+ (channel - nr_cpus));
+ } else {
+ reg = ENERGY_CORE_MSR;
+ cpu = channel;
+ }
+
+ if (!cpu_online(cpu))
+ return -ENODEV;
+
+ if (data->energy_units == 0 && get_energy_units(data))
+ return -EAGAIN;
+
+ mutex_lock(&data->lock);
+ ret = rdmsrl_safe_on_cpu(cpu, reg, &input);
+ if (ret)
+ return -EAGAIN;
+
+ /* Accumulation is for sockets only */
+ if (channel >= nr_cpus)
+ input += data->energy_ctrs[channel - nr_cpus];
+
+ /* Energy consumed = (1/(2^ESU) * RAW * 1000000UL) Joules */
+ *val = (long)input * div64_ul(1000000UL,
+ BIT(data->energy_units));
+ mutex_unlock(&data->lock);
+
+ return 0;
+}
+
+static umode_t amd_energy_is_visible(const void *_data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ return 0444;
+}
+
+static int socket_accumulator(void *p)
+{
+ struct amd_energy_data *data = (struct amd_energy_data *)p;
+
+ while (!kthread_should_stop()) {
+ mutex_lock(&data->lock);
+ read_accumulate(data);
+ mutex_unlock(&data->lock);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (kthread_should_stop())
+ break;
+
+ /*
+ * On a 240W system, the Socket Energy status
+ * register may wrap around in
+ * 2^32*15.3 e-6/240 = 273.8041 secs (~4.5 mins)
+ *
+ * let us accumulate for every 100secs
+ */
+ schedule_timeout(msecs_to_jiffies(100000));
+ }
+ return 0;
+}
+
+static const struct hwmon_ops amd_energy_ops = {
+ .is_visible = amd_energy_is_visible,
+ .read = amd_energy_read,
+ .read_string = amd_energy_read_labels,
+};
+
+static int amd_create_sensor(struct device *dev,
+ struct amd_energy_data *data,
+ u8 type, u32 config)
+{
+ int i;
+ u32 *s_config;
+
+ struct hwmon_channel_info *info = &data->energy_info;
+
+ nr_socks = num_possible_nodes();
+ nr_cpus = num_present_cpus();
+
+ s_config = devm_kcalloc(dev, nr_cpus + nr_socks,
+ sizeof(u32), GFP_KERNEL);
+ if (!s_config)
+ return -ENOMEM;
+
+ data->energy_ctrs = devm_kcalloc(dev, nr_socks,
+ sizeof(u64), GFP_KERNEL);
+ if (!data->energy_ctrs)
+ return -ENOMEM;
+
+ data->prev_value = devm_kcalloc(dev, nr_socks,
+ sizeof(u64), GFP_KERNEL);
+ if (!data->prev_value)
+ return -ENOMEM;
+
+ info->type = type;
+ info->config = s_config;
+
+ for (i = 0; i < nr_cpus + nr_socks; i++)
+ s_config[i] = config;
+
+ return 0;
+}
+
+static int amd_energy_probe(struct platform_device *pdev)
+{
+ struct device *hwmon_dev;
+ struct amd_energy_data *data;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ data = devm_kzalloc(dev,
+ sizeof(struct amd_energy_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->chip.ops = &amd_energy_ops;
+ data->chip.info = data->info;
+
+ /* Populate per-core energy reporting */
+ data->info[0] = &data->energy_info;
+ amd_create_sensor(dev, data, hwmon_energy,
+ HWMON_E_INPUT | HWMON_E_LABEL);
+
+ mutex_init(&data->lock);
+
+ ret = get_energy_units(data);
+ if (ret)
+ return ret;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, DRVNAME,
+ data,
+ &data->chip,
+ NULL);
+ if (IS_ERR(hwmon_dev))
+ return PTR_ERR(hwmon_dev);
+
+ wrap_accumulate = kthread_run(socket_accumulator, data,
+ "%s", dev_name(hwmon_dev));
+ if (IS_ERR(wrap_accumulate))
+ return PTR_ERR(wrap_accumulate);
+
+ return 0;
+}
+
+static int amd_energy_remove(struct platform_device *pdev)
+{
+ if (wrap_accumulate)
+ kthread_stop(wrap_accumulate);
+
+ return 0;
+}
+
+static const struct platform_device_id amd_energy_ids[] = {
+ { .name = DRVNAME, },
+ {}
+};
+MODULE_DEVICE_TABLE(platform, amd_energy_ids);
+
+static struct platform_driver amd_energy_driver = {
+ .probe = amd_energy_probe,
+ .remove = amd_energy_remove,
+ .id_table = amd_energy_ids,
+ .driver = {
+ .name = DRVNAME,
+ },
+};
+
+static struct platform_device *amd_energy_platdev;
+
+static const struct x86_cpu_id cpu_ids[] __initconst = {
+ X86_MATCH_VENDOR_FAM(AMD, 0x17, NULL),
+ X86_MATCH_VENDOR_FAM(AMD, 0x19, NULL),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, cpu_ids);
+
+static int __init amd_energy_init(void)
+{
+ int ret;
+
+ if (!x86_match_cpu(cpu_ids))
+ return -ENODEV;
+
+ ret = platform_driver_register(&amd_energy_driver);
+ if (ret < 0)
+ return ret;
+
+ amd_energy_platdev = platform_device_alloc(DRVNAME, 0);
+ if (!amd_energy_platdev)
+ return -ENOMEM;
+
+ ret = platform_device_add(amd_energy_platdev);
+ if (ret) {
+ platform_device_unregister(amd_energy_platdev);
+ return ret;
+ }
+
+ return ret;
+}
+
+static void __exit amd_energy_exit(void)
+{
+ platform_device_unregister(amd_energy_platdev);
+ platform_driver_unregister(&amd_energy_driver);
+}
+
+module_init(amd_energy_init);
+module_exit(amd_energy_exit);
+
+MODULE_DESCRIPTION("Driver for AMD Energy reporting from RAPL MSR via HWMON interface");
+MODULE_AUTHOR("Naveen Krishna Chatradhi <nchatrad@xxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.17.1
