2014-01-14 04:02:40 -07:00
|
|
|
/*
|
|
|
|
* cpuidle-powernv - idle state cpuidle driver.
|
|
|
|
* Adapted from drivers/cpuidle/cpuidle-pseries
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/init.h>
|
|
|
|
#include <linux/moduleparam.h>
|
|
|
|
#include <linux/cpuidle.h>
|
|
|
|
#include <linux/cpu.h>
|
|
|
|
#include <linux/notifier.h>
|
2014-02-25 17:09:06 -07:00
|
|
|
#include <linux/clockchips.h>
|
2014-02-25 17:09:20 -07:00
|
|
|
#include <linux/of.h>
|
2014-01-14 04:02:40 -07:00
|
|
|
|
|
|
|
#include <asm/machdep.h>
|
|
|
|
#include <asm/firmware.h>
|
2014-02-17 08:59:29 -07:00
|
|
|
#include <asm/runlatch.h>
|
2014-01-14 04:02:40 -07:00
|
|
|
|
2014-02-25 17:09:20 -07:00
|
|
|
/* Flags and constants used in PowerNV platform */
|
|
|
|
|
|
|
|
#define MAX_POWERNV_IDLE_STATES 8
|
|
|
|
#define IDLE_USE_INST_NAP 0x00010000 /* Use nap instruction */
|
|
|
|
#define IDLE_USE_INST_SLEEP 0x00020000 /* Use sleep instruction */
|
|
|
|
|
2014-01-14 04:02:40 -07:00
|
|
|
struct cpuidle_driver powernv_idle_driver = {
|
|
|
|
.name = "powernv_idle",
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
};
|
|
|
|
|
|
|
|
static int max_idle_state;
|
|
|
|
static struct cpuidle_state *cpuidle_state_table;
|
|
|
|
|
|
|
|
static int snooze_loop(struct cpuidle_device *dev,
|
|
|
|
struct cpuidle_driver *drv,
|
|
|
|
int index)
|
|
|
|
{
|
|
|
|
local_irq_enable();
|
|
|
|
set_thread_flag(TIF_POLLING_NRFLAG);
|
|
|
|
|
2014-02-17 08:59:29 -07:00
|
|
|
ppc64_runlatch_off();
|
2014-01-14 04:02:40 -07:00
|
|
|
while (!need_resched()) {
|
|
|
|
HMT_low();
|
|
|
|
HMT_very_low();
|
|
|
|
}
|
|
|
|
|
|
|
|
HMT_medium();
|
2014-02-17 08:59:29 -07:00
|
|
|
ppc64_runlatch_on();
|
2014-01-14 04:02:40 -07:00
|
|
|
clear_thread_flag(TIF_POLLING_NRFLAG);
|
|
|
|
smp_mb();
|
|
|
|
return index;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int nap_loop(struct cpuidle_device *dev,
|
|
|
|
struct cpuidle_driver *drv,
|
|
|
|
int index)
|
|
|
|
{
|
2014-02-17 08:59:29 -07:00
|
|
|
ppc64_runlatch_off();
|
2014-01-14 04:02:40 -07:00
|
|
|
power7_idle();
|
2014-02-17 08:59:29 -07:00
|
|
|
ppc64_runlatch_on();
|
2014-01-14 04:02:40 -07:00
|
|
|
return index;
|
|
|
|
}
|
|
|
|
|
2014-02-25 17:09:06 -07:00
|
|
|
static int fastsleep_loop(struct cpuidle_device *dev,
|
|
|
|
struct cpuidle_driver *drv,
|
|
|
|
int index)
|
|
|
|
{
|
|
|
|
unsigned long old_lpcr = mfspr(SPRN_LPCR);
|
|
|
|
unsigned long new_lpcr;
|
|
|
|
|
|
|
|
if (unlikely(system_state < SYSTEM_RUNNING))
|
|
|
|
return index;
|
|
|
|
|
|
|
|
new_lpcr = old_lpcr;
|
2014-06-10 23:59:27 -06:00
|
|
|
/* Do not exit powersave upon decrementer as we've setup the timer
|
|
|
|
* offload.
|
2014-02-25 17:09:06 -07:00
|
|
|
*/
|
2014-06-10 23:59:27 -06:00
|
|
|
new_lpcr &= ~LPCR_PECE1;
|
2014-02-25 17:09:06 -07:00
|
|
|
|
|
|
|
mtspr(SPRN_LPCR, new_lpcr);
|
|
|
|
power7_sleep();
|
|
|
|
|
|
|
|
mtspr(SPRN_LPCR, old_lpcr);
|
|
|
|
|
|
|
|
return index;
|
|
|
|
}
|
|
|
|
|
2014-01-14 04:02:40 -07:00
|
|
|
/*
|
|
|
|
* States for dedicated partition case.
|
|
|
|
*/
|
2014-02-25 17:09:20 -07:00
|
|
|
static struct cpuidle_state powernv_states[MAX_POWERNV_IDLE_STATES] = {
|
2014-01-14 04:02:40 -07:00
|
|
|
{ /* Snooze */
|
|
|
|
.name = "snooze",
|
|
|
|
.desc = "snooze",
|
|
|
|
.flags = CPUIDLE_FLAG_TIME_VALID,
|
|
|
|
.exit_latency = 0,
|
|
|
|
.target_residency = 0,
|
|
|
|
.enter = &snooze_loop },
|
|
|
|
};
|
|
|
|
|
|
|
|
static int powernv_cpuidle_add_cpu_notifier(struct notifier_block *n,
|
|
|
|
unsigned long action, void *hcpu)
|
|
|
|
{
|
|
|
|
int hotcpu = (unsigned long)hcpu;
|
|
|
|
struct cpuidle_device *dev =
|
|
|
|
per_cpu(cpuidle_devices, hotcpu);
|
|
|
|
|
|
|
|
if (dev && cpuidle_get_driver()) {
|
|
|
|
switch (action) {
|
|
|
|
case CPU_ONLINE:
|
|
|
|
case CPU_ONLINE_FROZEN:
|
|
|
|
cpuidle_pause_and_lock();
|
|
|
|
cpuidle_enable_device(dev);
|
|
|
|
cpuidle_resume_and_unlock();
|
|
|
|
break;
|
|
|
|
|
|
|
|
case CPU_DEAD:
|
|
|
|
case CPU_DEAD_FROZEN:
|
|
|
|
cpuidle_pause_and_lock();
|
|
|
|
cpuidle_disable_device(dev);
|
|
|
|
cpuidle_resume_and_unlock();
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
return NOTIFY_DONE;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return NOTIFY_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct notifier_block setup_hotplug_notifier = {
|
|
|
|
.notifier_call = powernv_cpuidle_add_cpu_notifier,
|
|
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
|
|
* powernv_cpuidle_driver_init()
|
|
|
|
*/
|
|
|
|
static int powernv_cpuidle_driver_init(void)
|
|
|
|
{
|
|
|
|
int idle_state;
|
|
|
|
struct cpuidle_driver *drv = &powernv_idle_driver;
|
|
|
|
|
|
|
|
drv->state_count = 0;
|
|
|
|
|
|
|
|
for (idle_state = 0; idle_state < max_idle_state; ++idle_state) {
|
|
|
|
/* Is the state not enabled? */
|
|
|
|
if (cpuidle_state_table[idle_state].enter == NULL)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
drv->states[drv->state_count] = /* structure copy */
|
|
|
|
cpuidle_state_table[idle_state];
|
|
|
|
|
|
|
|
drv->state_count += 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-02-25 17:09:20 -07:00
|
|
|
static int powernv_add_idle_states(void)
|
|
|
|
{
|
|
|
|
struct device_node *power_mgt;
|
|
|
|
struct property *prop;
|
|
|
|
int nr_idle_states = 1; /* Snooze */
|
|
|
|
int dt_idle_states;
|
|
|
|
u32 *flags;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
/* Currently we have snooze statically defined */
|
|
|
|
|
|
|
|
power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
|
|
|
|
if (!power_mgt) {
|
|
|
|
pr_warn("opal: PowerMgmt Node not found\n");
|
|
|
|
return nr_idle_states;
|
|
|
|
}
|
|
|
|
|
|
|
|
prop = of_find_property(power_mgt, "ibm,cpu-idle-state-flags", NULL);
|
|
|
|
if (!prop) {
|
|
|
|
pr_warn("DT-PowerMgmt: missing ibm,cpu-idle-state-flags\n");
|
|
|
|
return nr_idle_states;
|
|
|
|
}
|
|
|
|
|
|
|
|
dt_idle_states = prop->length / sizeof(u32);
|
|
|
|
flags = (u32 *) prop->value;
|
|
|
|
|
|
|
|
for (i = 0; i < dt_idle_states; i++) {
|
|
|
|
|
|
|
|
if (flags[i] & IDLE_USE_INST_NAP) {
|
|
|
|
/* Add NAP state */
|
|
|
|
strcpy(powernv_states[nr_idle_states].name, "Nap");
|
|
|
|
strcpy(powernv_states[nr_idle_states].desc, "Nap");
|
|
|
|
powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIME_VALID;
|
|
|
|
powernv_states[nr_idle_states].exit_latency = 10;
|
|
|
|
powernv_states[nr_idle_states].target_residency = 100;
|
|
|
|
powernv_states[nr_idle_states].enter = &nap_loop;
|
|
|
|
nr_idle_states++;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (flags[i] & IDLE_USE_INST_SLEEP) {
|
|
|
|
/* Add FASTSLEEP state */
|
|
|
|
strcpy(powernv_states[nr_idle_states].name, "FastSleep");
|
|
|
|
strcpy(powernv_states[nr_idle_states].desc, "FastSleep");
|
|
|
|
powernv_states[nr_idle_states].flags =
|
|
|
|
CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TIMER_STOP;
|
|
|
|
powernv_states[nr_idle_states].exit_latency = 300;
|
|
|
|
powernv_states[nr_idle_states].target_residency = 1000000;
|
|
|
|
powernv_states[nr_idle_states].enter = &fastsleep_loop;
|
|
|
|
nr_idle_states++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return nr_idle_states;
|
|
|
|
}
|
|
|
|
|
2014-01-14 04:02:40 -07:00
|
|
|
/*
|
|
|
|
* powernv_idle_probe()
|
|
|
|
* Choose state table for shared versus dedicated partition
|
|
|
|
*/
|
|
|
|
static int powernv_idle_probe(void)
|
|
|
|
{
|
|
|
|
if (cpuidle_disable != IDLE_NO_OVERRIDE)
|
|
|
|
return -ENODEV;
|
|
|
|
|
|
|
|
if (firmware_has_feature(FW_FEATURE_OPALv3)) {
|
|
|
|
cpuidle_state_table = powernv_states;
|
2014-02-25 17:09:20 -07:00
|
|
|
/* Device tree can indicate more idle states */
|
|
|
|
max_idle_state = powernv_add_idle_states();
|
2014-01-14 04:02:40 -07:00
|
|
|
} else
|
|
|
|
return -ENODEV;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int __init powernv_processor_idle_init(void)
|
|
|
|
{
|
|
|
|
int retval;
|
|
|
|
|
|
|
|
retval = powernv_idle_probe();
|
|
|
|
if (retval)
|
|
|
|
return retval;
|
|
|
|
|
|
|
|
powernv_cpuidle_driver_init();
|
|
|
|
retval = cpuidle_register(&powernv_idle_driver, NULL);
|
|
|
|
if (retval) {
|
|
|
|
printk(KERN_DEBUG "Registration of powernv driver failed.\n");
|
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
|
|
|
register_cpu_notifier(&setup_hotplug_notifier);
|
|
|
|
printk(KERN_DEBUG "powernv_idle_driver registered\n");
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
device_initcall(powernv_processor_idle_init);
|