blob: f968ffd9f6afc8969c43f16304dddbd2f3e42ebf [file] [log] [blame]
/* drivers/cpufreq/qcom-cpufreq.c
*
* MSM architecture cpufreq driver
*
* Copyright (C) 2007 Google, Inc.
* Copyright (c) 2007-2017, The Linux Foundation. All rights reserved.
* Author: Mike A. Chan <mikechan@google.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program 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.
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cpufreq.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/suspend.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <trace/events/power.h>
static DEFINE_MUTEX(l2bw_lock);
static struct clk *cpu_clk[NR_CPUS];
static struct clk *l2_clk;
static DEFINE_PER_CPU(struct cpufreq_frequency_table *, freq_table);
static bool hotplug_ready;
struct cpufreq_suspend_t {
struct mutex suspend_mutex;
int device_suspended;
};
static DEFINE_PER_CPU(struct cpufreq_suspend_t, suspend_data);
static int set_cpu_freq(struct cpufreq_policy *policy, unsigned int new_freq,
unsigned int index)
{
int ret = 0;
struct cpufreq_freqs freqs;
unsigned long rate;
freqs.old = policy->cur;
freqs.new = new_freq;
freqs.cpu = policy->cpu;
trace_cpu_frequency_switch_start(freqs.old, freqs.new, policy->cpu);
cpufreq_freq_transition_begin(policy, &freqs);
rate = new_freq * 1000;
rate = clk_round_rate(cpu_clk[policy->cpu], rate);
ret = clk_set_rate(cpu_clk[policy->cpu], rate);
cpufreq_freq_transition_end(policy, &freqs, ret);
if (!ret)
trace_cpu_frequency_switch_end(policy->cpu);
return ret;
}
static int msm_cpufreq_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
int ret = 0;
int index;
struct cpufreq_frequency_table *table;
mutex_lock(&per_cpu(suspend_data, policy->cpu).suspend_mutex);
if (target_freq == policy->cur)
goto done;
if (per_cpu(suspend_data, policy->cpu).device_suspended) {
pr_debug("cpufreq: cpu%d scheduling frequency change in suspend.\n",
policy->cpu);
ret = -EFAULT;
goto done;
}
table = policy->freq_table;
if (!table) {
pr_err("cpufreq: Failed to get frequency table for CPU%u\n",
policy->cpu);
ret = -ENODEV;
goto done;
}
index = cpufreq_frequency_table_target(policy, target_freq, relation);
pr_debug("CPU[%d] target %d relation %d (%d-%d) selected %d\n",
policy->cpu, target_freq, relation,
policy->min, policy->max, table[index].frequency);
ret = set_cpu_freq(policy, table[index].frequency,
table[index].driver_data);
done:
mutex_unlock(&per_cpu(suspend_data, policy->cpu).suspend_mutex);
return ret;
}
static int msm_cpufreq_verify(struct cpufreq_policy *policy)
{
cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
policy->cpuinfo.max_freq);
return 0;
}
static unsigned int msm_cpufreq_get_freq(unsigned int cpu)
{
return clk_get_rate(cpu_clk[cpu]) / 1000;
}
static int msm_cpufreq_init(struct cpufreq_policy *policy)
{
int cur_freq;
int index;
int ret = 0;
struct cpufreq_frequency_table *table =
per_cpu(freq_table, policy->cpu);
int cpu;
/*
* In some SoC, some cores are clocked by same source, and their
* frequencies can not be changed independently. Find all other
* CPUs that share same clock, and mark them as controlled by
* same policy.
*/
for_each_possible_cpu(cpu)
if (cpu_clk[cpu] == cpu_clk[policy->cpu])
cpumask_set_cpu(cpu, policy->cpus);
ret = cpufreq_table_validate_and_show(policy, table);
if (ret) {
pr_err("cpufreq: failed to get policy min/max\n");
return ret;
}
cur_freq = clk_get_rate(cpu_clk[policy->cpu])/1000;
index = cpufreq_frequency_table_target(policy, cur_freq,
CPUFREQ_RELATION_H);
/*
* Call set_cpu_freq unconditionally so that when cpu is set to
* online, frequency limit will always be updated.
*/
ret = set_cpu_freq(policy, table[index].frequency,
table[index].driver_data);
if (ret)
return ret;
pr_debug("cpufreq: cpu%d init at %d switching to %d\n",
policy->cpu, cur_freq, table[index].frequency);
policy->cur = table[index].frequency;
return 0;
}
static int qcom_cpufreq_dead_cpu(unsigned int cpu)
{
/* Fail hotplug until this driver can get CPU clocks */
if (!hotplug_ready)
return -EINVAL;
clk_unprepare(cpu_clk[cpu]);
clk_unprepare(l2_clk);
return 0;
}
static int qcom_cpufreq_up_cpu(unsigned int cpu)
{
int rc;
/* Fail hotplug until this driver can get CPU clocks */
if (!hotplug_ready)
return -EINVAL;
rc = clk_prepare(l2_clk);
if (rc < 0)
return rc;
rc = clk_prepare(cpu_clk[cpu]);
if (rc < 0)
clk_unprepare(l2_clk);
return rc;
}
static int qcom_cpufreq_dying_cpu(unsigned int cpu)
{
/* Fail hotplug until this driver can get CPU clocks */
if (!hotplug_ready)
return -EINVAL;
clk_disable(cpu_clk[cpu]);
clk_disable(l2_clk);
return 0;
}
static int qcom_cpufreq_starting_cpu(unsigned int cpu)
{
int rc;
/* Fail hotplug until this driver can get CPU clocks */
if (!hotplug_ready)
return -EINVAL;
rc = clk_enable(l2_clk);
if (rc < 0)
return rc;
rc = clk_enable(cpu_clk[cpu]);
if (rc < 0)
clk_disable(l2_clk);
return rc;
}
static int msm_cpufreq_suspend(void)
{
int cpu;
for_each_possible_cpu(cpu) {
mutex_lock(&per_cpu(suspend_data, cpu).suspend_mutex);
per_cpu(suspend_data, cpu).device_suspended = 1;
mutex_unlock(&per_cpu(suspend_data, cpu).suspend_mutex);
}
return NOTIFY_DONE;
}
static int msm_cpufreq_resume(void)
{
int cpu, ret;
struct cpufreq_policy policy;
for_each_possible_cpu(cpu) {
per_cpu(suspend_data, cpu).device_suspended = 0;
}
/*
* Freq request might be rejected during suspend, resulting
* in policy->cur violating min/max constraint.
* Correct the frequency as soon as possible.
*/
get_online_cpus();
for_each_online_cpu(cpu) {
ret = cpufreq_get_policy(&policy, cpu);
if (ret)
continue;
if (policy.cur <= policy.max && policy.cur >= policy.min)
continue;
ret = cpufreq_update_policy(cpu);
if (ret)
pr_info("cpufreq: Current frequency violates policy min/max for CPU%d\n",
cpu);
else
pr_info("cpufreq: Frequency violation fixed for CPU%d\n",
cpu);
}
put_online_cpus();
return NOTIFY_DONE;
}
static int msm_cpufreq_pm_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
switch (event) {
case PM_POST_HIBERNATION:
case PM_POST_SUSPEND:
return msm_cpufreq_resume();
case PM_HIBERNATION_PREPARE:
case PM_SUSPEND_PREPARE:
return msm_cpufreq_suspend();
default:
return NOTIFY_DONE;
}
}
static struct notifier_block msm_cpufreq_pm_notifier = {
.notifier_call = msm_cpufreq_pm_event,
};
static struct freq_attr *msm_freq_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
NULL,
};
static struct cpufreq_driver msm_cpufreq_driver = {
/* lps calculations are handled here. */
.flags = CPUFREQ_STICKY | CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.init = msm_cpufreq_init,
.verify = msm_cpufreq_verify,
.target = msm_cpufreq_target,
.get = msm_cpufreq_get_freq,
.name = "msm",
.attr = msm_freq_attr,
};
static struct cpufreq_frequency_table *cpufreq_parse_dt(struct device *dev,
char *tbl_name, int cpu)
{
int ret, nf, i, j;
u32 *data;
struct cpufreq_frequency_table *ftbl;
/* Parse list of usable CPU frequencies. */
if (!of_find_property(dev->of_node, tbl_name, &nf))
return ERR_PTR(-EINVAL);
nf /= sizeof(*data);
if (nf == 0)
return ERR_PTR(-EINVAL);
data = devm_kzalloc(dev, nf * sizeof(*data), GFP_KERNEL);
if (!data)
return ERR_PTR(-ENOMEM);
ret = of_property_read_u32_array(dev->of_node, tbl_name, data, nf);
if (ret)
return ERR_PTR(ret);
ftbl = devm_kzalloc(dev, (nf + 1) * sizeof(*ftbl), GFP_KERNEL);
if (!ftbl)
return ERR_PTR(-ENOMEM);
j = 0;
for (i = 0; i < nf; i++) {
unsigned long f;
f = clk_round_rate(cpu_clk[cpu], data[i] * 1000);
if (IS_ERR_VALUE(f))
break;
f /= 1000;
/*
* Don't repeat frequencies if they round up to the same clock
* frequency.
*
*/
if (j > 0 && f <= ftbl[j - 1].frequency)
continue;
ftbl[j].driver_data = j;
ftbl[j].frequency = f;
j++;
}
ftbl[j].driver_data = j;
ftbl[j].frequency = CPUFREQ_TABLE_END;
devm_kfree(dev, data);
return ftbl;
}
static int msm_cpufreq_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
char clk_name[] = "cpu??_clk";
char tbl_name[] = "qcom,cpufreq-table-??";
struct clk *c;
int cpu, ret;
struct cpufreq_frequency_table *ftbl;
l2_clk = devm_clk_get(dev, "l2_clk");
if (IS_ERR(l2_clk))
l2_clk = NULL;
for_each_possible_cpu(cpu) {
snprintf(clk_name, sizeof(clk_name), "cpu%d_clk", cpu);
c = devm_clk_get(dev, clk_name);
if (cpu == 0 && IS_ERR(c))
return PTR_ERR(c);
else if (IS_ERR(c))
c = cpu_clk[cpu-1];
cpu_clk[cpu] = c;
}
hotplug_ready = true;
/* Use per-policy governor tunable for some targets */
if (of_property_read_bool(dev->of_node, "qcom,governor-per-policy"))
msm_cpufreq_driver.flags |= CPUFREQ_HAVE_GOVERNOR_PER_POLICY;
/* Parse commong cpufreq table for all CPUs */
ftbl = cpufreq_parse_dt(dev, "qcom,cpufreq-table", 0);
if (!IS_ERR(ftbl)) {
for_each_possible_cpu(cpu)
per_cpu(freq_table, cpu) = ftbl;
return 0;
}
/*
* No common table. Parse individual tables for each unique
* CPU clock.
*/
for_each_possible_cpu(cpu) {
snprintf(tbl_name, sizeof(tbl_name),
"qcom,cpufreq-table-%d", cpu);
ftbl = cpufreq_parse_dt(dev, tbl_name, cpu);
/* CPU0 must contain freq table */
if (cpu == 0 && IS_ERR(ftbl)) {
dev_err(dev, "Failed to parse CPU0's freq table\n");
return PTR_ERR(ftbl);
}
if (cpu == 0) {
per_cpu(freq_table, cpu) = ftbl;
continue;
}
if (cpu_clk[cpu] != cpu_clk[cpu - 1] && IS_ERR(ftbl)) {
dev_err(dev, "Failed to parse CPU%d's freq table\n",
cpu);
return PTR_ERR(ftbl);
}
/* Use previous CPU's table if it shares same clock */
if (cpu_clk[cpu] == cpu_clk[cpu - 1]) {
if (!IS_ERR(ftbl)) {
dev_warn(dev, "Conflicting tables for CPU%d\n",
cpu);
devm_kfree(dev, ftbl);
}
ftbl = per_cpu(freq_table, cpu - 1);
}
per_cpu(freq_table, cpu) = ftbl;
}
ret = register_pm_notifier(&msm_cpufreq_pm_notifier);
if (ret)
return ret;
ret = cpufreq_register_driver(&msm_cpufreq_driver);
if (ret)
unregister_pm_notifier(&msm_cpufreq_pm_notifier);
return ret;
}
static const struct of_device_id msm_cpufreq_match_table[] = {
{ .compatible = "qcom,msm-cpufreq" },
{}
};
static struct platform_driver msm_cpufreq_plat_driver = {
.probe = msm_cpufreq_probe,
.driver = {
.name = "msm-cpufreq",
.of_match_table = msm_cpufreq_match_table,
},
};
static int __init msm_cpufreq_register(void)
{
int cpu, rc;
for_each_possible_cpu(cpu) {
mutex_init(&(per_cpu(suspend_data, cpu).suspend_mutex));
per_cpu(suspend_data, cpu).device_suspended = 0;
}
rc = platform_driver_register(&msm_cpufreq_plat_driver);
if (rc < 0) {
/* Unblock hotplug if msm-cpufreq probe fails */
cpuhp_remove_state_nocalls(CPUHP_QCOM_CPUFREQ_PREPARE);
cpuhp_remove_state_nocalls(CPUHP_AP_QCOM_CPUFREQ_STARTING);
for_each_possible_cpu(cpu)
mutex_destroy(&(per_cpu(suspend_data, cpu).
suspend_mutex));
return rc;
}
return 0;
}
subsys_initcall(msm_cpufreq_register);
static int __init msm_cpufreq_early_register(void)
{
int ret;
ret = cpuhp_setup_state_nocalls(CPUHP_AP_QCOM_CPUFREQ_STARTING,
"AP_QCOM_CPUFREQ_STARTING",
qcom_cpufreq_starting_cpu,
qcom_cpufreq_dying_cpu);
if (ret)
return ret;
ret = cpuhp_setup_state_nocalls(CPUHP_QCOM_CPUFREQ_PREPARE,
"QCOM_CPUFREQ_PREPARE",
qcom_cpufreq_up_cpu,
qcom_cpufreq_dead_cpu);
if (!ret)
return ret;
cpuhp_remove_state_nocalls(CPUHP_AP_QCOM_CPUFREQ_STARTING);
return ret;
}
core_initcall(msm_cpufreq_early_register);