![Rafael J. Wysocki](/assets/img/avatar_default.png)
* pm-opp: cpufreq: OMAP: Register an Energy Model cpufreq: imx6q: Register an Energy Model opp: no need to check return value of debugfs_create functions cpufreq: mediatek: Register an Energy Model cpufreq: scmi: Register an Energy Model cpufreq: arm_big_little: Register an Energy Model cpufreq: scpi: Register an Energy Model cpufreq: dt: Register an Energy Model
280 lines
6.5 KiB
C
280 lines
6.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* System Control and Power Interface (SCMI) based CPUFreq Interface driver
|
|
*
|
|
* Copyright (C) 2018 ARM Ltd.
|
|
* Sudeep Holla <sudeep.holla@arm.com>
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/cpu.h>
|
|
#include <linux/cpufreq.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/energy_model.h>
|
|
#include <linux/export.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pm_opp.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/scmi_protocol.h>
|
|
#include <linux/types.h>
|
|
|
|
struct scmi_data {
|
|
int domain_id;
|
|
struct device *cpu_dev;
|
|
};
|
|
|
|
static const struct scmi_handle *handle;
|
|
|
|
static unsigned int scmi_cpufreq_get_rate(unsigned int cpu)
|
|
{
|
|
struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
|
|
struct scmi_perf_ops *perf_ops = handle->perf_ops;
|
|
struct scmi_data *priv = policy->driver_data;
|
|
unsigned long rate;
|
|
int ret;
|
|
|
|
ret = perf_ops->freq_get(handle, priv->domain_id, &rate, false);
|
|
if (ret)
|
|
return 0;
|
|
return rate / 1000;
|
|
}
|
|
|
|
/*
|
|
* perf_ops->freq_set is not a synchronous, the actual OPP change will
|
|
* happen asynchronously and can get notified if the events are
|
|
* subscribed for by the SCMI firmware
|
|
*/
|
|
static int
|
|
scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index)
|
|
{
|
|
int ret;
|
|
struct scmi_data *priv = policy->driver_data;
|
|
struct scmi_perf_ops *perf_ops = handle->perf_ops;
|
|
u64 freq = policy->freq_table[index].frequency;
|
|
|
|
ret = perf_ops->freq_set(handle, priv->domain_id, freq * 1000, false);
|
|
if (!ret)
|
|
arch_set_freq_scale(policy->related_cpus, freq,
|
|
policy->cpuinfo.max_freq);
|
|
return ret;
|
|
}
|
|
|
|
static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,
|
|
unsigned int target_freq)
|
|
{
|
|
struct scmi_data *priv = policy->driver_data;
|
|
struct scmi_perf_ops *perf_ops = handle->perf_ops;
|
|
|
|
if (!perf_ops->freq_set(handle, priv->domain_id,
|
|
target_freq * 1000, true)) {
|
|
arch_set_freq_scale(policy->related_cpus, target_freq,
|
|
policy->cpuinfo.max_freq);
|
|
return target_freq;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
|
|
{
|
|
int cpu, domain, tdomain;
|
|
struct device *tcpu_dev;
|
|
|
|
domain = handle->perf_ops->device_domain_id(cpu_dev);
|
|
if (domain < 0)
|
|
return domain;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
if (cpu == cpu_dev->id)
|
|
continue;
|
|
|
|
tcpu_dev = get_cpu_device(cpu);
|
|
if (!tcpu_dev)
|
|
continue;
|
|
|
|
tdomain = handle->perf_ops->device_domain_id(tcpu_dev);
|
|
if (tdomain == domain)
|
|
cpumask_set_cpu(cpu, cpumask);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused
|
|
scmi_get_cpu_power(unsigned long *power, unsigned long *KHz, int cpu)
|
|
{
|
|
struct device *cpu_dev = get_cpu_device(cpu);
|
|
unsigned long Hz;
|
|
int ret, domain;
|
|
|
|
if (!cpu_dev) {
|
|
pr_err("failed to get cpu%d device\n", cpu);
|
|
return -ENODEV;
|
|
}
|
|
|
|
domain = handle->perf_ops->device_domain_id(cpu_dev);
|
|
if (domain < 0)
|
|
return domain;
|
|
|
|
/* Get the power cost of the performance domain. */
|
|
Hz = *KHz * 1000;
|
|
ret = handle->perf_ops->est_power_get(handle, domain, &Hz, power);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* The EM framework specifies the frequency in KHz. */
|
|
*KHz = Hz / 1000;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int scmi_cpufreq_init(struct cpufreq_policy *policy)
|
|
{
|
|
int ret, nr_opp;
|
|
unsigned int latency;
|
|
struct device *cpu_dev;
|
|
struct scmi_data *priv;
|
|
struct cpufreq_frequency_table *freq_table;
|
|
struct em_data_callback em_cb = EM_DATA_CB(scmi_get_cpu_power);
|
|
|
|
cpu_dev = get_cpu_device(policy->cpu);
|
|
if (!cpu_dev) {
|
|
pr_err("failed to get cpu%d device\n", policy->cpu);
|
|
return -ENODEV;
|
|
}
|
|
|
|
ret = handle->perf_ops->device_opps_add(handle, cpu_dev);
|
|
if (ret) {
|
|
dev_warn(cpu_dev, "failed to add opps to the device\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = scmi_get_sharing_cpus(cpu_dev, policy->cpus);
|
|
if (ret) {
|
|
dev_warn(cpu_dev, "failed to get sharing cpumask\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus);
|
|
if (ret) {
|
|
dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
|
|
nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
|
|
if (nr_opp <= 0) {
|
|
dev_dbg(cpu_dev, "OPP table is not ready, deferring probe\n");
|
|
ret = -EPROBE_DEFER;
|
|
goto out_free_opp;
|
|
}
|
|
|
|
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
|
|
if (!priv) {
|
|
ret = -ENOMEM;
|
|
goto out_free_opp;
|
|
}
|
|
|
|
ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
|
|
if (ret) {
|
|
dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
|
|
goto out_free_priv;
|
|
}
|
|
|
|
priv->cpu_dev = cpu_dev;
|
|
priv->domain_id = handle->perf_ops->device_domain_id(cpu_dev);
|
|
|
|
policy->driver_data = priv;
|
|
policy->freq_table = freq_table;
|
|
|
|
/* SCMI allows DVFS request for any domain from any CPU */
|
|
policy->dvfs_possible_from_any_cpu = true;
|
|
|
|
latency = handle->perf_ops->transition_latency_get(handle, cpu_dev);
|
|
if (!latency)
|
|
latency = CPUFREQ_ETERNAL;
|
|
|
|
policy->cpuinfo.transition_latency = latency;
|
|
|
|
policy->fast_switch_possible = true;
|
|
|
|
em_register_perf_domain(policy->cpus, nr_opp, &em_cb);
|
|
|
|
return 0;
|
|
|
|
out_free_priv:
|
|
kfree(priv);
|
|
out_free_opp:
|
|
dev_pm_opp_remove_all_dynamic(cpu_dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int scmi_cpufreq_exit(struct cpufreq_policy *policy)
|
|
{
|
|
struct scmi_data *priv = policy->driver_data;
|
|
|
|
dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
|
|
dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
|
|
kfree(priv);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct cpufreq_driver scmi_cpufreq_driver = {
|
|
.name = "scmi",
|
|
.flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
|
|
CPUFREQ_NEED_INITIAL_FREQ_CHECK |
|
|
CPUFREQ_IS_COOLING_DEV,
|
|
.verify = cpufreq_generic_frequency_table_verify,
|
|
.attr = cpufreq_generic_attr,
|
|
.target_index = scmi_cpufreq_set_target,
|
|
.fast_switch = scmi_cpufreq_fast_switch,
|
|
.get = scmi_cpufreq_get_rate,
|
|
.init = scmi_cpufreq_init,
|
|
.exit = scmi_cpufreq_exit,
|
|
};
|
|
|
|
static int scmi_cpufreq_probe(struct scmi_device *sdev)
|
|
{
|
|
int ret;
|
|
|
|
handle = sdev->handle;
|
|
|
|
if (!handle || !handle->perf_ops)
|
|
return -ENODEV;
|
|
|
|
ret = cpufreq_register_driver(&scmi_cpufreq_driver);
|
|
if (ret) {
|
|
dev_err(&sdev->dev, "%s: registering cpufreq failed, err: %d\n",
|
|
__func__, ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void scmi_cpufreq_remove(struct scmi_device *sdev)
|
|
{
|
|
cpufreq_unregister_driver(&scmi_cpufreq_driver);
|
|
}
|
|
|
|
static const struct scmi_device_id scmi_id_table[] = {
|
|
{ SCMI_PROTOCOL_PERF },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(scmi, scmi_id_table);
|
|
|
|
static struct scmi_driver scmi_cpufreq_drv = {
|
|
.name = "scmi-cpufreq",
|
|
.probe = scmi_cpufreq_probe,
|
|
.remove = scmi_cpufreq_remove,
|
|
.id_table = scmi_id_table,
|
|
};
|
|
module_scmi_driver(scmi_cpufreq_drv);
|
|
|
|
MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
|
|
MODULE_DESCRIPTION("ARM SCMI CPUFreq interface driver");
|
|
MODULE_LICENSE("GPL v2");
|