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Merge branch 'pm-cpuidle' 

* pm-cpuidle:
  cpuidle: Fix ARCH_NEEDS_CPU_IDLE_COUPLED dependency warning
  cpuidle: Comment the driver's framework code
  cpuidle: simplify multiple driver support
  ARM: zynq: Add cpuidle support
  cpuidle: improve governor Kconfig options
This commit is contained in:
Rafael J. Wysocki 2013-06-28 13:01:06 +02:00
parent 3e79a8a67d b39b0981b0
commit 93bc11c3cc
7 changed files with 339 additions and 163 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
MAINTAINERS
View File

@ -1311,6 +1311,7 @@ W: http://wiki.xilinx.com
T: git git://git.xilinx.com/linux-xlnx.git
S: Supported
F: arch/arm/mach-zynq/
F: drivers/cpuidle/cpuidle-zynq.c
ARM64 PORT (AARCH64 ARCHITECTURE)
M: Catalin Marinas <catalin.marinas@arm.com>

27
drivers/cpuidle/Kconfig
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@ -1,7 +1,9 @@
config CPU_IDLE
menuconfig CPU_IDLE
bool "CPU idle PM support"
default y if ACPI || PPC_PSERIES
select CPU_IDLE_GOV_LADDER if (!NO_HZ && !NO_HZ_IDLE)
select CPU_IDLE_GOV_MENU if (NO_HZ || NO_HZ_IDLE)
help
CPU idle is a generic framework for supporting software-controlled
idle processor power management. It includes modular cross-platform
@ -9,9 +11,10 @@ config CPU_IDLE
If you're using an ACPI-enabled platform, you should say Y here.
if CPU_IDLE
config CPU_IDLE_MULTIPLE_DRIVERS
bool "Support multiple cpuidle drivers"
depends on CPU_IDLE
default n
help
Allows the cpuidle framework to use different drivers for each CPU.
@ -19,24 +22,26 @@ config CPU_IDLE_MULTIPLE_DRIVERS
states. If unsure say N.
config CPU_IDLE_GOV_LADDER
bool
depends on CPU_IDLE
bool "Ladder governor (for periodic timer tick)"
default y
config CPU_IDLE_GOV_MENU
bool
depends on CPU_IDLE && NO_HZ
bool "Menu governor (for tickless system)"
default y
config ARCH_NEEDS_CPU_IDLE_COUPLED
def_bool n
if CPU_IDLE
config CPU_IDLE_CALXEDA
bool "CPU Idle Driver for Calxeda processors"
depends on ARCH_HIGHBANK
help
Select this to enable cpuidle on Calxeda processors.
config CPU_IDLE_ZYNQ
bool "CPU Idle Driver for Xilinx Zynq processors"
depends on ARCH_ZYNQ
help
Select this to enable cpuidle on Xilinx Zynq processors.
endif
config ARCH_NEEDS_CPU_IDLE_COUPLED
def_bool n

1
drivers/cpuidle/Makefile
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@ -7,3 +7,4 @@ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o
obj-$(CONFIG_ARCH_KIRKWOOD) += cpuidle-kirkwood.o
obj-$(CONFIG_CPU_IDLE_ZYNQ) += cpuidle-zynq.o

83
drivers/cpuidle/cpuidle-zynq.c Normal file
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@ -0,0 +1,83 @@
/*
* Copyright (C) 2012-2013 Xilinx
*
* CPU idle support for Xilinx Zynq
*
* based on arch/arm/mach-at91/cpuidle.c
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*
* The cpu idle uses wait-for-interrupt and RAM self refresh in order
* to implement two idle states -
* #1 wait-for-interrupt
* #2 wait-for-interrupt and RAM self refresh
*
* Maintainer: Michal Simek <michal.simek@xilinx.com>
*/
#include <linux/init.h>
#include <linux/cpu_pm.h>
#include <linux/cpuidle.h>
#include <linux/of.h>
#include <asm/proc-fns.h>
#include <asm/cpuidle.h>
#define ZYNQ_MAX_STATES 2
/* Actual code that puts the SoC in different idle states */
static int zynq_enter_idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
/* Devices must be stopped here */
cpu_pm_enter();
/* Add code for DDR self refresh start */
cpu_do_idle();
/* Add code for DDR self refresh stop */
cpu_pm_exit();
return index;
}
static struct cpuidle_driver zynq_idle_driver = {
.name = "zynq_idle",
.owner = THIS_MODULE,
.states = {
ARM_CPUIDLE_WFI_STATE,
{
.enter = zynq_enter_idle,
.exit_latency = 10,
.target_residency = 10000,
.flags = CPUIDLE_FLAG_TIME_VALID |
CPUIDLE_FLAG_TIMER_STOP,
.name = "RAM_SR",
.desc = "WFI and RAM Self Refresh",
},
},
.safe_state_index = 0,
.state_count = ZYNQ_MAX_STATES,
};
/* Initialize CPU idle by registering the idle states */
static int __init zynq_cpuidle_init(void)
{
if (!of_machine_is_compatible("xlnx,zynq-7000"))
return -ENODEV;
pr_info("Xilinx Zynq CpuIdle Driver started\n");
return cpuidle_register(&zynq_idle_driver, NULL);
}
device_initcall(zynq_cpuidle_init);

4
drivers/cpuidle/cpuidle.c
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@ -466,7 +466,7 @@ void cpuidle_unregister(struct cpuidle_driver *drv)
int cpu;
struct cpuidle_device *device;
for_each_possible_cpu(cpu) {
for_each_cpu(cpu, drv->cpumask) {
device = &per_cpu(cpuidle_dev, cpu);
cpuidle_unregister_device(device);
}
@ -498,7 +498,7 @@ int cpuidle_register(struct cpuidle_driver *drv,
return ret;
}
for_each_possible_cpu(cpu) {
for_each_cpu(cpu, drv->cpumask) {
device = &per_cpu(cpuidle_dev, cpu);
device->cpu = cpu;

380
drivers/cpuidle/driver.c
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@ -18,182 +18,249 @@
DEFINE_SPINLOCK(cpuidle_driver_lock);
static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu);
static struct cpuidle_driver * __cpuidle_get_cpu_driver(int cpu);
static void cpuidle_setup_broadcast_timer(void *arg)
{
int cpu = smp_processor_id();
clockevents_notify((long)(arg), &cpu);
}
static void __cpuidle_driver_init(struct cpuidle_driver *drv, int cpu)
{
int i;
drv->refcnt = 0;
for (i = drv->state_count - 1; i >= 0 ; i--) {
if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP))
continue;
drv->bctimer = 1;
on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
(void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
break;
}
}
static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu)
{
if (!drv || !drv->state_count)
return -EINVAL;
if (cpuidle_disabled())
return -ENODEV;
if (__cpuidle_get_cpu_driver(cpu))
return -EBUSY;
__cpuidle_driver_init(drv, cpu);
__cpuidle_set_cpu_driver(drv, cpu);
return 0;
}
static void __cpuidle_unregister_driver(struct cpuidle_driver *drv, int cpu)
{
if (drv != __cpuidle_get_cpu_driver(cpu))
return;
if (!WARN_ON(drv->refcnt > 0))
__cpuidle_set_cpu_driver(NULL, cpu);
if (drv->bctimer) {
drv->bctimer = 0;
on_each_cpu_mask(get_cpu_mask(cpu), cpuidle_setup_broadcast_timer,
(void *)CLOCK_EVT_NOTIFY_BROADCAST_OFF, 1);
}
}
#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS
static DEFINE_PER_CPU(struct cpuidle_driver *, cpuidle_drivers);
static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu)
{
per_cpu(cpuidle_drivers, cpu) = drv;
}
/**
* __cpuidle_get_cpu_driver - return the cpuidle driver tied to a CPU.
* @cpu: the CPU handled by the driver
*
* Returns a pointer to struct cpuidle_driver or NULL if no driver has been
* registered for @cpu.
*/
static struct cpuidle_driver *__cpuidle_get_cpu_driver(int cpu)
{
return per_cpu(cpuidle_drivers, cpu);
}
static void __cpuidle_unregister_all_cpu_driver(struct cpuidle_driver *drv)
/**
* __cpuidle_unset_driver - unset per CPU driver variables.
* @drv: a valid pointer to a struct cpuidle_driver
*
* For each CPU in the driver's CPU mask, unset the registered driver per CPU
* variable. If @drv is different from the registered driver, the corresponding
* variable is not cleared.
*/
static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv)
{
int cpu;
for_each_present_cpu(cpu)
__cpuidle_unregister_driver(drv, cpu);
for_each_cpu(cpu, drv->cpumask) {
if (drv != __cpuidle_get_cpu_driver(cpu))
continue;
per_cpu(cpuidle_drivers, cpu) = NULL;
}
}
static int __cpuidle_register_all_cpu_driver(struct cpuidle_driver *drv)
/**
* __cpuidle_set_driver - set per CPU driver variables the the given driver.
* @drv: a valid pointer to a struct cpuidle_driver
*
* For each CPU in the driver's cpumask, unset the registered driver per CPU
* to @drv.
*
* Returns 0 on success, -EBUSY if the CPUs have driver(s) already.
*/
static inline int __cpuidle_set_driver(struct cpuidle_driver *drv)
{
int ret = 0;
int i, cpu;
int cpu;
for_each_present_cpu(cpu) {
ret = __cpuidle_register_driver(drv, cpu);
if (ret)
break;
}
for_each_cpu(cpu, drv->cpumask) {
if (ret)
for_each_present_cpu(i) {
if (i == cpu)
break;
__cpuidle_unregister_driver(drv, i);
if (__cpuidle_get_cpu_driver(cpu)) {
__cpuidle_unset_driver(drv);
return -EBUSY;
}
per_cpu(cpuidle_drivers, cpu) = drv;
}
return ret;
return 0;
}
int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu)
{
int ret;
spin_lock(&cpuidle_driver_lock);
ret = __cpuidle_register_driver(drv, cpu);
spin_unlock(&cpuidle_driver_lock);
return ret;
}
void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu)
{
spin_lock(&cpuidle_driver_lock);
__cpuidle_unregister_driver(drv, cpu);
spin_unlock(&cpuidle_driver_lock);
}
/**
* cpuidle_register_driver - registers a driver
* @drv: the driver
*/
int cpuidle_register_driver(struct cpuidle_driver *drv)
{
int ret;
spin_lock(&cpuidle_driver_lock);
ret = __cpuidle_register_all_cpu_driver(drv);
spin_unlock(&cpuidle_driver_lock);
return ret;
}
EXPORT_SYMBOL_GPL(cpuidle_register_driver);
/**
* cpuidle_unregister_driver - unregisters a driver
* @drv: the driver
*/
void cpuidle_unregister_driver(struct cpuidle_driver *drv)
{
spin_lock(&cpuidle_driver_lock);
__cpuidle_unregister_all_cpu_driver(drv);
spin_unlock(&cpuidle_driver_lock);
}
EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
#else
static struct cpuidle_driver *cpuidle_curr_driver;
static inline void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu)
{
cpuidle_curr_driver = drv;
}
/**
* __cpuidle_get_cpu_driver - return the global cpuidle driver pointer.
* @cpu: ignored without the multiple driver support
*
* Return a pointer to a struct cpuidle_driver object or NULL if no driver was
* previously registered.
*/
static inline struct cpuidle_driver *__cpuidle_get_cpu_driver(int cpu)
{
return cpuidle_curr_driver;
}
/**
* __cpuidle_set_driver - assign the global cpuidle driver variable.
* @drv: pointer to a struct cpuidle_driver object
*
* Returns 0 on success, -EBUSY if the driver is already registered.
*/
static inline int __cpuidle_set_driver(struct cpuidle_driver *drv)
{
if (cpuidle_curr_driver)
return -EBUSY;
cpuidle_curr_driver = drv;
return 0;
}
/**
* __cpuidle_unset_driver - unset the global cpuidle driver variable.
* @drv: a pointer to a struct cpuidle_driver
*
* Reset the global cpuidle variable to NULL. If @drv does not match the
* registered driver, do nothing.
*/
static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv)
{
if (drv == cpuidle_curr_driver)
cpuidle_curr_driver = NULL;
}
#endif
/**
* cpuidle_setup_broadcast_timer - enable/disable the broadcast timer
* @arg: a void pointer used to match the SMP cross call API
*
* @arg is used as a value of type 'long' with on of the two values:
* - CLOCK_EVT_NOTIFY_BROADCAST_ON
* - CLOCK_EVT_NOTIFY_BROADCAST_OFF
*
* Set the broadcast timer notification for the current CPU. This function
* is executed per CPU by an SMP cross call. It not supposed to be called
* directly.
*/
static void cpuidle_setup_broadcast_timer(void *arg)
{
int cpu = smp_processor_id();
clockevents_notify((long)(arg), &cpu);
}
/**
* __cpuidle_driver_init - initialize the driver's internal data
* @drv: a valid pointer to a struct cpuidle_driver
*
* Returns 0 on success, a negative error code otherwise.
*/
static int __cpuidle_driver_init(struct cpuidle_driver *drv)
{
int i;
drv->refcnt = 0;
/*
* Use all possible CPUs as the default, because if the kernel boots
* with some CPUs offline and then we online one of them, the CPU
* notifier has to know which driver to assign.
*/
if (!drv->cpumask)
drv->cpumask = (struct cpumask *)cpu_possible_mask;
/*
* Look for the timer stop flag in the different states, so that we know
* if the broadcast timer has to be set up. The loop is in the reverse
* order, because usually on of the the deeper states has this flag set.
*/
for (i = drv->state_count - 1; i >= 0 ; i--) {
if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP))
continue;
drv->bctimer = 1;
break;
}
return 0;
}
/**
* __cpuidle_register_driver: register the driver
* @drv: a valid pointer to a struct cpuidle_driver
*
* Do some sanity checks, initialize the driver, assign the driver to the
* global cpuidle driver variable(s) and set up the broadcast timer if the
* cpuidle driver has some states that shut down the local timer.
*
* Returns 0 on success, a negative error code otherwise:
* * -EINVAL if the driver pointer is NULL or no idle states are available
* * -ENODEV if the cpuidle framework is disabled
* * -EBUSY if the driver is already assigned to the global variable(s)
*/
static int __cpuidle_register_driver(struct cpuidle_driver *drv)
{
int ret;
if (!drv || !drv->state_count)
return -EINVAL;
if (cpuidle_disabled())
return -ENODEV;
ret = __cpuidle_driver_init(drv);
if (ret)
return ret;
ret = __cpuidle_set_driver(drv);
if (ret)
return ret;
if (drv->bctimer)
on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer,
(void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
return 0;
}
/**
* __cpuidle_unregister_driver - unregister the driver
* @drv: a valid pointer to a struct cpuidle_driver
*
* Check if the driver is no longer in use, reset the global cpuidle driver
* variable(s) and disable the timer broadcast notification mechanism if it was
* in use.
*
*/
static void __cpuidle_unregister_driver(struct cpuidle_driver *drv)
{
if (WARN_ON(drv->refcnt > 0))
return;
if (drv->bctimer) {
drv->bctimer = 0;
on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer,
(void *)CLOCK_EVT_NOTIFY_BROADCAST_OFF, 1);
}
__cpuidle_unset_driver(drv);
}
/**
* cpuidle_register_driver - registers a driver
* @drv: the driver
* @drv: a pointer to a valid struct cpuidle_driver
*
* Register the driver under a lock to prevent concurrent attempts to
* [un]register the driver from occuring at the same time.
*
* Returns 0 on success, a negative error code (returned by
* __cpuidle_register_driver()) otherwise.
*/
int cpuidle_register_driver(struct cpuidle_driver *drv)
{
int ret, cpu;
int ret;
cpu = get_cpu();
spin_lock(&cpuidle_driver_lock);
ret = __cpuidle_register_driver(drv, cpu);
ret = __cpuidle_register_driver(drv);
spin_unlock(&cpuidle_driver_lock);
put_cpu();
return ret;
}
@ -201,23 +268,24 @@ EXPORT_SYMBOL_GPL(cpuidle_register_driver);
/**
* cpuidle_unregister_driver - unregisters a driver
* @drv: the driver
* @drv: a pointer to a valid struct cpuidle_driver
*
* Unregisters the cpuidle driver under a lock to prevent concurrent attempts
* to [un]register the driver from occuring at the same time. @drv has to
* match the currently registered driver.
*/
void cpuidle_unregister_driver(struct cpuidle_driver *drv)
{
int cpu;
cpu = get_cpu();
spin_lock(&cpuidle_driver_lock);
__cpuidle_unregister_driver(drv, cpu);
__cpuidle_unregister_driver(drv);
spin_unlock(&cpuidle_driver_lock);
put_cpu();
}
EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
#endif
/**
* cpuidle_get_driver - return the current driver
* cpuidle_get_driver - return the driver tied to the current CPU.
*
* Returns a struct cpuidle_driver pointer, or NULL if no driver is registered.
*/
struct cpuidle_driver *cpuidle_get_driver(void)
{
@ -233,7 +301,11 @@ struct cpuidle_driver *cpuidle_get_driver(void)
EXPORT_SYMBOL_GPL(cpuidle_get_driver);
/**
* cpuidle_get_cpu_driver - return the driver tied with a cpu
* cpuidle_get_cpu_driver - return the driver registered for a CPU.
* @dev: a valid pointer to a struct cpuidle_device
*
* Returns a struct cpuidle_driver pointer, or NULL if no driver is registered
* for the CPU associated with @dev.
*/
struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev)
{
@ -244,6 +316,14 @@ struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev)
}
EXPORT_SYMBOL_GPL(cpuidle_get_cpu_driver);
/**
* cpuidle_driver_ref - get a reference to the driver.
*
* Increment the reference counter of the cpuidle driver associated with
* the current CPU.
*
* Returns a pointer to the driver, or NULL if the current CPU has no driver.
*/
struct cpuidle_driver *cpuidle_driver_ref(void)
{
struct cpuidle_driver *drv;
@ -257,6 +337,12 @@ struct cpuidle_driver *cpuidle_driver_ref(void)
return drv;
}
/**
* cpuidle_driver_unref - puts down the refcount for the driver
*
* Decrement the reference counter of the cpuidle driver associated with
* the current CPU.
*/
void cpuidle_driver_unref(void)
{
struct cpuidle_driver *drv = cpuidle_get_driver();

6
include/linux/cpuidle.h
View File

@ -111,6 +111,9 @@ struct cpuidle_driver {
struct cpuidle_state states[CPUIDLE_STATE_MAX];
int state_count;
int safe_state_index;
/* the driver handles the cpus in cpumask */
struct cpumask *cpumask;
};
#ifdef CONFIG_CPU_IDLE
@ -135,9 +138,6 @@ extern void cpuidle_disable_device(struct cpuidle_device *dev);
extern int cpuidle_play_dead(void);
extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev);
extern int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu);
extern void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu);
#else
static inline void disable_cpuidle(void) { }
static inline int cpuidle_idle_call(void) { return -ENODEV; }