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/* arch/arm/mach-msm/cpufreq.c
*
* MSM architecture cpufreq driver
*
* Copyright (C) 2007 Google, Inc.
* Copyright (c) 2007-2013, 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/earlysuspend.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cpufreq.h>
#include <linux/workqueue.h>
#include <linux/completion.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/sched.h>
#include <linux/suspend.h>
#include <mach/socinfo.h>
#include <mach/cpufreq.h>
#include "acpuclock.h"
struct cpufreq_work_struct {
struct work_struct work;
struct cpufreq_policy *policy;
struct completion complete;
int frequency;
int status;
};
static DEFINE_PER_CPU(struct cpufreq_work_struct, cpufreq_work);
static struct workqueue_struct *msm_cpufreq_wq;
struct cpufreq_suspend_t {
struct mutex suspend_mutex;
int device_suspended;
};
static DEFINE_PER_CPU(struct cpufreq_suspend_t, cpufreq_suspend);
struct cpu_freq {
uint32_t max;
uint32_t min;
uint32_t allowed_max;
uint32_t allowed_min;
uint32_t limits_init;
};
static DEFINE_PER_CPU(struct cpu_freq, cpu_freq_info);
static int set_cpu_freq(struct cpufreq_policy *policy, unsigned int new_freq)
{
int ret = 0;
int saved_sched_policy = -EINVAL;
int saved_sched_rt_prio = -EINVAL;
struct cpufreq_freqs freqs;
struct cpu_freq *limit = &per_cpu(cpu_freq_info, policy->cpu);
struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
if (limit->limits_init) {
if (new_freq > limit->allowed_max) {
new_freq = limit->allowed_max;
pr_debug("max: limiting freq to %d\n", new_freq);
}
if (new_freq < limit->allowed_min) {
new_freq = limit->allowed_min;
pr_debug("min: limiting freq to %d\n", new_freq);
}
}
freqs.old = policy->cur;
freqs.new = new_freq;
freqs.cpu = policy->cpu;
/*
* Put the caller into SCHED_FIFO priority to avoid cpu starvation
* in the acpuclk_set_rate path while increasing frequencies
*/
if (freqs.new > freqs.old && current->policy != SCHED_FIFO) {
saved_sched_policy = current->policy;
saved_sched_rt_prio = current->rt_priority;
sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
}
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
ret = acpuclk_set_rate(policy->cpu, new_freq, SETRATE_CPUFREQ);
if (!ret)
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
/* Restore priority after clock ramp-up */
if (freqs.new > freqs.old && saved_sched_policy >= 0) {
param.sched_priority = saved_sched_rt_prio;
sched_setscheduler_nocheck(current, saved_sched_policy, &param);
}
return ret;
}
static void set_cpu_work(struct work_struct *work)
{
struct cpufreq_work_struct *cpu_work =
container_of(work, struct cpufreq_work_struct, work);
cpu_work->status = set_cpu_freq(cpu_work->policy, cpu_work->frequency);
complete(&cpu_work->complete);
}
static int msm_cpufreq_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
int ret = -EFAULT;
int index;
struct cpufreq_frequency_table *table;
struct cpufreq_work_struct *cpu_work = NULL;
mutex_lock(&per_cpu(cpufreq_suspend, policy->cpu).suspend_mutex);
if (per_cpu(cpufreq_suspend, policy->cpu).device_suspended) {
pr_debug("cpufreq: cpu%d scheduling frequency change "
"in suspend.\n", policy->cpu);
ret = -EFAULT;
goto done;
}
table = cpufreq_frequency_get_table(policy->cpu);
if (cpufreq_frequency_table_target(policy, table, target_freq, relation,
&index)) {
pr_err("cpufreq: invalid target_freq: %d\n", target_freq);
ret = -EINVAL;
goto done;
}
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);
cpu_work = &per_cpu(cpufreq_work, policy->cpu);
cpu_work->policy = policy;
cpu_work->frequency = table[index].frequency;
cpu_work->status = -ENODEV;
cancel_work_sync(&cpu_work->work);
INIT_COMPLETION(cpu_work->complete);
queue_work_on(policy->cpu, msm_cpufreq_wq, &cpu_work->work);
wait_for_completion(&cpu_work->complete);
ret = cpu_work->status;
done:
mutex_unlock(&per_cpu(cpufreq_suspend, 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 acpuclk_get_rate(cpu);
}
static inline int msm_cpufreq_limits_init(void)
{
int cpu = 0;
int i = 0;
struct cpufreq_frequency_table *table = NULL;
uint32_t min = (uint32_t) -1;
uint32_t max = 0;
struct cpu_freq *limit = NULL;
for_each_possible_cpu(cpu) {
limit = &per_cpu(cpu_freq_info, cpu);
table = cpufreq_frequency_get_table(cpu);
if (table == NULL) {
pr_err("%s: error reading cpufreq table for cpu %d\n",
__func__, cpu);
continue;
}
for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
if (table[i].frequency > max)
max = table[i].frequency;
if (table[i].frequency < min)
min = table[i].frequency;
}
limit->allowed_min = min;
limit->allowed_max = max;
limit->min = min;
limit->max = max;
limit->limits_init = 1;
}
return 0;
}
int msm_cpufreq_set_freq_limits(uint32_t cpu, uint32_t min, uint32_t max)
{
struct cpu_freq *limit = &per_cpu(cpu_freq_info, cpu);
if (!limit->limits_init)
msm_cpufreq_limits_init();
if ((min != MSM_CPUFREQ_NO_LIMIT) &&
min >= limit->min && min <= limit->max)
limit->allowed_min = min;
else
limit->allowed_min = limit->min;
if ((max != MSM_CPUFREQ_NO_LIMIT) &&
max <= limit->max && max >= limit->min)
limit->allowed_max = max;
else
limit->allowed_max = limit->max;
pr_debug("%s: Limiting cpu %d min = %d, max = %d\n",
__func__, cpu,
limit->allowed_min, limit->allowed_max);
return 0;
}
EXPORT_SYMBOL(msm_cpufreq_set_freq_limits);
static int __cpuinit msm_cpufreq_init(struct cpufreq_policy *policy)
{
int cur_freq;
int index;
int ret = 0;
struct cpufreq_frequency_table *table;
struct cpufreq_work_struct *cpu_work = NULL;
table = cpufreq_frequency_get_table(policy->cpu);
if (table == NULL)
return -ENODEV;
/*
* In 8625, 8610, and 8226 both cpu core's frequency can not
* be changed independently. Each cpu is bound to
* same frequency. Hence set the cpumask to all cpu.
*/
if (cpu_is_msm8625() || cpu_is_msm8625q() || cpu_is_msm8226()
|| cpu_is_msm8610())
cpumask_setall(policy->cpus);
if (cpufreq_frequency_table_cpuinfo(policy, table)) {
#ifdef CONFIG_MSM_CPU_FREQ_SET_MIN_MAX
policy->cpuinfo.min_freq = CONFIG_MSM_CPU_FREQ_MIN;
policy->cpuinfo.max_freq = CONFIG_MSM_CPU_FREQ_MAX;
#endif
}
#ifdef CONFIG_MSM_CPU_FREQ_SET_MIN_MAX
policy->min = CONFIG_MSM_CPU_FREQ_MIN;
policy->max = CONFIG_MSM_CPU_FREQ_MAX;
#endif
cur_freq = acpuclk_get_rate(policy->cpu);
if (cpufreq_frequency_table_target(policy, table, cur_freq,
CPUFREQ_RELATION_H, &index) &&
cpufreq_frequency_table_target(policy, table, cur_freq,
CPUFREQ_RELATION_L, &index)) {
pr_info("cpufreq: cpu%d at invalid freq: %d\n",
policy->cpu, cur_freq);
return -EINVAL;
}
/*
* 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);
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;
policy->cpuinfo.transition_latency =
acpuclk_get_switch_time() * NSEC_PER_USEC;
cpu_work = &per_cpu(cpufreq_work, policy->cpu);
INIT_WORK(&cpu_work->work, set_cpu_work);
init_completion(&cpu_work->complete);
return 0;
}
static int __cpuinit msm_cpufreq_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
switch (action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
per_cpu(cpufreq_suspend, cpu).device_suspended = 0;
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
mutex_lock(&per_cpu(cpufreq_suspend, cpu).suspend_mutex);
per_cpu(cpufreq_suspend, cpu).device_suspended = 1;
mutex_unlock(&per_cpu(cpufreq_suspend, cpu).suspend_mutex);
break;
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
per_cpu(cpufreq_suspend, cpu).device_suspended = 0;
break;
}
return NOTIFY_OK;
}
static struct notifier_block __refdata msm_cpufreq_cpu_notifier = {
.notifier_call = msm_cpufreq_cpu_callback,
};
/*
* Define suspend/resume for cpufreq_driver. Kernel will call
* these during suspend/resume with interrupts disabled. This
* helps the suspend/resume variable get's updated before cpufreq
* governor tries to change the frequency after coming out of suspend.
*/
static int msm_cpufreq_suspend(struct cpufreq_policy *policy)
{
int cpu;
for_each_possible_cpu(cpu) {
per_cpu(cpufreq_suspend, cpu).device_suspended = 1;
}
return 0;
}
static int msm_cpufreq_resume(struct cpufreq_policy *policy)
{
int cpu;
for_each_possible_cpu(cpu) {
per_cpu(cpufreq_suspend, cpu).device_suspended = 0;
}
return 0;
}
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,
.init = msm_cpufreq_init,
.verify = msm_cpufreq_verify,
.target = msm_cpufreq_target,
.get = msm_cpufreq_get_freq,
.suspend = msm_cpufreq_suspend,
.resume = msm_cpufreq_resume,
.name = "msm",
.attr = msm_freq_attr,
};
static int __init msm_cpufreq_register(void)
{
int cpu;
for_each_possible_cpu(cpu) {
mutex_init(&(per_cpu(cpufreq_suspend, cpu).suspend_mutex));
per_cpu(cpufreq_suspend, cpu).device_suspended = 0;
}
msm_cpufreq_wq = alloc_workqueue("msm-cpufreq", WQ_HIGHPRI, 0);
register_hotcpu_notifier(&msm_cpufreq_cpu_notifier);
return cpufreq_register_driver(&msm_cpufreq_driver);
}
device_initcall(msm_cpufreq_register);