blob: 8f086aaa933421cc16b37cbe27eab8041edaf0e7 [file] [log] [blame]
/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/kobject.h>
#include <linux/cpufreq.h>
#include <linux/platform_device.h>
#include <linux/cpu_pm.h>
#include <linux/pm_qos.h>
#include <linux/hrtimer.h>
#include <linux/tick.h>
#include <mach/msm_dcvs.h>
struct cpu_idle_info {
int enabled;
int dcvs_core_id;
struct pm_qos_request pm_qos_req;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_idle_info, cpu_idle_info);
static DEFINE_PER_CPU_SHARED_ALIGNED(u64, iowait_on_cpu);
static uint32_t latency;
static int msm_dcvs_idle_notifier(int core_num,
enum msm_core_control_event event)
{
struct cpu_idle_info *info = &per_cpu(cpu_idle_info, core_num);
switch (event) {
case MSM_DCVS_ENABLE_IDLE_PULSE:
info->enabled = true;
break;
case MSM_DCVS_DISABLE_IDLE_PULSE:
info->enabled = false;
break;
case MSM_DCVS_ENABLE_HIGH_LATENCY_MODES:
pm_qos_update_request(&info->pm_qos_req, PM_QOS_DEFAULT_VALUE);
break;
case MSM_DCVS_DISABLE_HIGH_LATENCY_MODES:
pm_qos_update_request(&info->pm_qos_req, latency);
break;
}
return 0;
}
static int msm_cpuidle_notifier(struct notifier_block *self, unsigned long cmd,
void *v)
{
struct cpu_idle_info *info =
&per_cpu(cpu_idle_info, smp_processor_id());
u64 io_wait_us = 0;
u64 prev_io_wait_us = 0;
u64 last_update_time = 0;
u64 val = 0;
uint32_t iowaited = 0;
if (!info->enabled)
return NOTIFY_OK;
switch (cmd) {
case CPU_PM_ENTER:
val = get_cpu_iowait_time_us(smp_processor_id(),
&last_update_time);
/* val could be -1 when NOHZ is not enabled */
if (val == (u64)-1)
val = 0;
per_cpu(iowait_on_cpu, smp_processor_id()) = val;
msm_dcvs_idle(info->dcvs_core_id, MSM_DCVS_IDLE_ENTER, 0);
break;
case CPU_PM_EXIT:
prev_io_wait_us = per_cpu(iowait_on_cpu, smp_processor_id());
val = get_cpu_iowait_time_us(smp_processor_id(),
&last_update_time);
if (val == (u64)-1)
val = 0;
io_wait_us = val;
iowaited = (io_wait_us - prev_io_wait_us);
msm_dcvs_idle(info->dcvs_core_id, MSM_DCVS_IDLE_EXIT, iowaited);
break;
}
return NOTIFY_OK;
}
static struct notifier_block idle_nb = {
.notifier_call = msm_cpuidle_notifier,
};
static void msm_gov_idle_source_init(int cpu, int dcvs_core_id)
{
struct cpu_idle_info *info = NULL;
info = &per_cpu(cpu_idle_info, cpu);
info->dcvs_core_id = dcvs_core_id;
pm_qos_add_request(&info->pm_qos_req, PM_QOS_CPU_DMA_LATENCY,
PM_QOS_DEFAULT_VALUE);
}
struct msm_gov {
int cpu;
unsigned int cur_freq;
unsigned int min_freq;
unsigned int max_freq;
struct cpufreq_policy *policy;
int dcvs_core_id;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct mutex, gov_mutex);
static DEFINE_PER_CPU_SHARED_ALIGNED(struct msm_gov, msm_gov_info);
static void msm_gov_check_limits(struct cpufreq_policy *policy)
{
struct msm_gov *gov = &per_cpu(msm_gov_info, policy->cpu);
if (policy->max < gov->cur_freq)
__cpufreq_driver_target(policy, policy->max,
CPUFREQ_RELATION_H);
else if (policy->min > gov->cur_freq)
__cpufreq_driver_target(policy, policy->min,
CPUFREQ_RELATION_L);
else
__cpufreq_driver_target(policy, gov->cur_freq,
CPUFREQ_RELATION_L);
gov->cur_freq = policy->cur;
gov->min_freq = policy->min;
gov->max_freq = policy->max;
msm_dcvs_update_limits(gov->dcvs_core_id);
}
static int msm_dcvs_freq_set(int core_num,
unsigned int freq)
{
int ret = -EINVAL;
struct msm_gov *gov = &per_cpu(msm_gov_info, core_num);
mutex_lock(&per_cpu(gov_mutex, gov->cpu));
if (freq < gov->min_freq)
freq = gov->min_freq;
if (freq > gov->max_freq)
freq = gov->max_freq;
mutex_unlock(&per_cpu(gov_mutex, gov->cpu));
ret = cpufreq_driver_target(gov->policy, freq, CPUFREQ_RELATION_L);
if (!ret) {
gov->cur_freq = cpufreq_quick_get(gov->cpu);
if (freq != gov->cur_freq)
pr_err("cpu %d freq %u gov->cur_freq %u didn't match",
gov->cpu, freq, gov->cur_freq);
}
ret = gov->cur_freq;
return ret;
}
static unsigned int msm_dcvs_freq_get(int core_num)
{
struct msm_gov *gov = &per_cpu(msm_gov_info, core_num);
/*
* the rw_sem in cpufreq is always held when this is called.
* The policy->cur won't be updated in this case - so it is safe to
* access policy->cur
*/
return gov->policy->cur;
}
static int cpufreq_governor_msm(struct cpufreq_policy *policy,
unsigned int event)
{
unsigned int cpu = policy->cpu;
int ret = 0;
int handle = 0;
struct msm_gov *gov = &per_cpu(msm_gov_info, policy->cpu);
switch (event) {
case CPUFREQ_GOV_START:
if (!cpu_online(cpu))
return -EINVAL;
BUG_ON(!policy->cur);
mutex_lock(&per_cpu(gov_mutex, cpu));
per_cpu(msm_gov_info, cpu).cpu = cpu;
gov->policy = policy;
handle = msm_dcvs_freq_sink_start(gov->dcvs_core_id);
BUG_ON(handle < 0);
msm_gov_check_limits(policy);
mutex_unlock(&per_cpu(gov_mutex, cpu));
break;
case CPUFREQ_GOV_STOP:
msm_dcvs_freq_sink_stop(gov->dcvs_core_id);
break;
case CPUFREQ_GOV_LIMITS:
mutex_lock(&per_cpu(gov_mutex, cpu));
msm_gov_check_limits(policy);
mutex_unlock(&per_cpu(gov_mutex, cpu));
break;
};
return ret;
}
struct cpufreq_governor cpufreq_gov_msm = {
.name = "msm-dcvs",
.governor = cpufreq_governor_msm,
.owner = THIS_MODULE,
};
static int __devinit msm_gov_probe(struct platform_device *pdev)
{
int cpu;
struct msm_dcvs_core_info *core = NULL;
struct msm_dcvs_core_info *core_info = NULL;
struct msm_gov_platform_data *pdata = pdev->dev.platform_data;
int sensor = 0;
core = pdev->dev.platform_data;
core_info = pdata->info;
latency = pdata->latency;
for_each_possible_cpu(cpu) {
struct msm_gov *gov = &per_cpu(msm_gov_info, cpu);
mutex_init(&per_cpu(gov_mutex, cpu));
if (cpu < core->num_cores)
sensor = core_info->sensors[cpu];
gov->dcvs_core_id = msm_dcvs_register_core(
MSM_DCVS_CORE_TYPE_CPU,
cpu,
core_info,
msm_dcvs_freq_set,
msm_dcvs_freq_get,
msm_dcvs_idle_notifier,
NULL,
sensor);
if (gov->dcvs_core_id < 0) {
pr_err("Unable to register core for %d\n", cpu);
return -EINVAL;
}
msm_gov_idle_source_init(cpu, gov->dcvs_core_id);
}
cpu_pm_register_notifier(&idle_nb);
return cpufreq_register_governor(&cpufreq_gov_msm);
}
static int __devexit msm_gov_remove(struct platform_device *pdev)
{
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver msm_gov_driver = {
.probe = msm_gov_probe,
.remove = __devexit_p(msm_gov_remove),
.driver = {
.name = "msm_dcvs_gov",
.owner = THIS_MODULE,
},
};
static int __init cpufreq_gov_msm_init(void)
{
return platform_driver_register(&msm_gov_driver);
}
late_initcall(cpufreq_gov_msm_init);