On 5/19/20 8:50 AM, Naveen Krishna Chatradhi wrote:
> 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>
> ---
This version looks ok, and it looks like there are no more
unexpected counter wraps either. Series applied to hwmon-next.
Thanks,
Guenter
> Changes in v7:
> 1. Move all static variables into the data structure
> 2. Move the read-update code under the mutex lock
>
> drivers/hwmon/Kconfig | 10 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/amd_energy.c | 406 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 417 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..bc8b643a37d5
> --- /dev/null
> +++ b/drivers/hwmon/amd_energy.c
> @@ -0,0 +1,406 @@
> +// 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/delay.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/sched.h>
> +#include <linux/slab.h>
> +#include <linux/topology.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
> +#define AMD_ENERGY_MASK 0xFFFFFFFF
> +
> +struct sensor_accumulator {
> + u64 energy_ctr;
> + u64 prev_value;
> + char label[10];
> +};
> +
> +struct amd_energy_data {
> + struct hwmon_channel_info energy_info;
> + const struct hwmon_channel_info *info[2];
> + struct hwmon_chip_info chip;
> + struct task_struct *wrap_accumulate;
> + /* Lock around the accumulator */
> + struct mutex lock;
> + /* An accumulator for each core and socket */
> + struct sensor_accumulator *accums;
> + /* Energy Status Units */
> + u64 energy_units;
> + int nr_cpus;
> + int nr_socks;
> + int core_id;
> +};
> +
> +static int amd_energy_read_labels(struct device *dev,
> + enum hwmon_sensor_types type,
> + u32 attr, int channel,
> + const char **str)
> +{
> + struct amd_energy_data *data = dev_get_drvdata(dev);
> +
> + *str = data->accums[channel].label;
> + return 0;
> +}
> +
> +static void get_energy_units(struct amd_energy_data *data)
> +{
> + u64 rapl_units;
> +
> + rdmsrl_safe(ENERGY_PWR_UNIT_MSR, &rapl_units);
> + data->energy_units = (rapl_units & AMD_ENERGY_UNIT_MASK) >> 8;
> +}
> +
> +static void accumulate_socket_delta(struct amd_energy_data *data,
> + int sock, int cpu)
> +{
> + struct sensor_accumulator *s_accum;
> + u64 input;
> +
> + mutex_lock(&data->lock);
> + rdmsrl_safe_on_cpu(cpu, ENERGY_PKG_MSR, &input);
> + input &= AMD_ENERGY_MASK;
> +
> + s_accum = &data->accums[data->nr_cpus + sock];
> + if (input >= s_accum->prev_value)
> + s_accum->energy_ctr +=
> + input - s_accum->prev_value;
> + else
> + s_accum->energy_ctr += UINT_MAX -
> + s_accum->prev_value + input;
> +
> + s_accum->prev_value = input;
> + mutex_unlock(&data->lock);
> +}
> +
> +static void accumulate_core_delta(struct amd_energy_data *data)
> +{
> + struct sensor_accumulator *c_accum;
> + u64 input;
> + int cpu;
> +
> + mutex_lock(&data->lock);
> + if (data->core_id >= data->nr_cpus)
> + data->core_id = 0;
> +
> + cpu = data->core_id;
> +
> + if (!cpu_online(cpu))
> + goto out;
> +
> + rdmsrl_safe_on_cpu(cpu, ENERGY_CORE_MSR, &input);
> + input &= AMD_ENERGY_MASK;
> +
> + c_accum = &data->accums[cpu];
> +
> + if (input >= c_accum->prev_value)
> + c_accum->energy_ctr +=
> + input - c_accum->prev_value;
> + else
> + c_accum->energy_ctr += UINT_MAX -
> + c_accum->prev_value + input;
> +
> + c_accum->prev_value = input;
> +
> +out:
> + data->core_id++;
> + mutex_unlock(&data->lock);
> +}
> +
> +static void read_accumulate(struct amd_energy_data *data)
> +{
> + int sock;
> +
> + for (sock = 0; sock < data->nr_socks; sock++) {
> + int cpu;
> +
> + cpu = cpumask_first_and(cpu_online_mask,
> + cpumask_of_node(sock));
> +
> + accumulate_socket_delta(data, sock, cpu);
> + }
> +
> + accumulate_core_delta(data);
> +}
> +
> +static void amd_add_delta(struct amd_energy_data *data, int ch,
> + int cpu, long *val, bool is_core)
> +{
> + struct sensor_accumulator *s_accum, *c_accum;
> + u64 input;
> +
> + mutex_lock(&data->lock);
> + if (!is_core) {
> + rdmsrl_safe_on_cpu(cpu, ENERGY_PKG_MSR, &input);
> + input &= AMD_ENERGY_MASK;
> +
> + s_accum = &data->accums[ch];
> + if (input >= s_accum->prev_value)
> + input += s_accum->energy_ctr -
> + s_accum->prev_value;
> + else
> + input += UINT_MAX - s_accum->prev_value +
> + s_accum->energy_ctr;
> + } else {
> + rdmsrl_safe_on_cpu(cpu, ENERGY_CORE_MSR, &input);
> + input &= AMD_ENERGY_MASK;
> +
> + c_accum = &data->accums[ch];
> + if (input >= c_accum->prev_value)
> + input += c_accum->energy_ctr -
> + c_accum->prev_value;
> + else
> + input += UINT_MAX - c_accum->prev_value +
> + c_accum->energy_ctr;
> + }
> +
> + /* Energy consumed = (1/(2^ESU) * RAW * 1000000UL) μJoules */
> + *val = div64_ul(input * 1000000UL, BIT(data->energy_units));
> +
> + mutex_unlock(&data->lock);
> +}
> +
> +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 cpu;
> +
> + if (channel >= data->nr_cpus) {
> + cpu = cpumask_first_and(cpu_online_mask,
> + cpumask_of_node
> + (channel - data->nr_cpus));
> + amd_add_delta(data, channel, cpu, val, false);
> + } else {
> + cpu = channel;
> + if (!cpu_online(cpu))
> + return -ENODEV;
> +
> + amd_add_delta(data, channel, cpu, val, true);
> + }
> +
> + 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 energy_accumulator(void *p)
> +{
> + struct amd_energy_data *data = (struct amd_energy_data *)p;
> +
> + while (!kthread_should_stop()) {
> + /*
> + * Ignoring the conditions such as
> + * cpu being offline or rdmsr failure
> + */
> + read_accumulate(data);
> +
> + set_current_state(TASK_INTERRUPTIBLE);
> + if (kthread_should_stop())
> + break;
> +
> + /*
> + * On a 240W system, with default resolution 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)
> +{
> + struct hwmon_channel_info *info = &data->energy_info;
> + struct sensor_accumulator *accums;
> + int i, num_siblings, cpus, sockets;
> + u32 *s_config;
> +
> + /* Identify the number of siblings per core */
> + num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
> +
> + sockets = num_possible_nodes();
> +
> + /*
> + * Energy counter register is accessed at core level.
> + * Hence, filterout the siblings.
> + */
> + cpus = num_present_cpus() / num_siblings;
> +
> + s_config = devm_kcalloc(dev, cpus + sockets,
> + sizeof(u32), GFP_KERNEL);
> + if (!s_config)
> + return -ENOMEM;
> +
> + accums = devm_kcalloc(dev, cpus + sockets,
> + sizeof(struct sensor_accumulator),
> + GFP_KERNEL);
> + if (!accums)
> + return -ENOMEM;
> +
> + info->type = type;
> + info->config = s_config;
> +
> + data->nr_cpus = cpus;
> + data->nr_socks = sockets;
> + data->accums = accums;
> +
> + for (i = 0; i < cpus + sockets; i++) {
> + s_config[i] = config;
> + if (i < cpus)
> + scnprintf(accums[i].label, 10,
> + "Ecore%03u", i);
> + else
> + scnprintf(accums[i].label, 10,
> + "Esocket%u", (i - cpus));
> + }
> +
> + 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;
> +
> + 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;
> +
> + dev_set_drvdata(dev, data);
> + /* 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);
> + get_energy_units(data);
> +
> + hwmon_dev = devm_hwmon_device_register_with_info(dev, DRVNAME,
> + data,
> + &data->chip,
> + NULL);
> + if (IS_ERR(hwmon_dev))
> + return PTR_ERR(hwmon_dev);
> +
> + data->wrap_accumulate = kthread_run(energy_accumulator, data,
> + "%s", dev_name(hwmon_dev));
> + if (IS_ERR(data->wrap_accumulate))
> + return PTR_ERR(data->wrap_accumulate);
> +
> + return PTR_ERR_OR_ZERO(data->wrap_accumulate);
> +}
> +
> +static int amd_energy_remove(struct platform_device *pdev)
> +{
> + struct amd_energy_data *data = dev_get_drvdata(&pdev->dev);
> +
> + if (data && data->wrap_accumulate)
> + kthread_stop(data->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),
> + {}
> +};
> +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)
> + 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_put(amd_energy_platdev);
> + platform_driver_unregister(&amd_energy_driver);
> + 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");
>
