From mboxrd@z Thu Jan 1 00:00:00 1970 From: rob.lee@linaro.org (Robert Lee) Date: Mon, 23 Jan 2012 22:37:28 -0600 Subject: [PATCH v3 1/7] cpuidle: Add common init interface and idle functionality In-Reply-To: <1327379854-12403-1-git-send-email-rob.lee@linaro.org> References: <1327379854-12403-1-git-send-email-rob.lee@linaro.org> Message-ID: <1327379854-12403-2-git-send-email-rob.lee@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The patch adds some cpuidle initialization functionality commonly duplicated by many platforms. Signed-off-by: Robert Lee --- drivers/cpuidle/Makefile | 2 +- drivers/cpuidle/common.c | 152 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/cpuidle.h | 24 +++++++ 3 files changed, 177 insertions(+), 1 deletions(-) create mode 100644 drivers/cpuidle/common.c diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 5634f88..2928d93 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -2,4 +2,4 @@ # Makefile for cpuidle. # -obj-y += cpuidle.o driver.o governor.o sysfs.o governors/ +obj-y += cpuidle.o driver.o governor.o sysfs.o common.o governors/ diff --git a/drivers/cpuidle/common.c b/drivers/cpuidle/common.c new file mode 100644 index 0000000..dafa758 --- /dev/null +++ b/drivers/cpuidle/common.c @@ -0,0 +1,152 @@ +/* + * Copyright 2011 Freescale Semiconductor, Inc. + * Copyright 2011 Linaro Ltd. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/* + * This code performs provides some commonly used cpuidle setup functionality + * used by many ARM SoC platforms. Providing this functionality here + * reduces the duplication of this code for each ARM platform that uses it. + */ + +#include +#include +#include +#include +#include +#include +#include + +static struct cpuidle_device __percpu * common_cpuidle_devices; + +static int (*do_idle[CPUIDLE_STATE_MAX])(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index); + +int cpuidle_def_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + cpu_do_idle(); + return index; +} + +static int simple_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + ktime_t time_start, time_end; + + local_irq_disable(); + + time_start = ktime_get(); + + index = do_idle[index](dev, drv, index); + + time_end = ktime_get(); + + local_irq_enable(); + + dev->last_residency = + (int)ktime_to_us(ktime_sub(time_end, time_start)); + + return index; +} + +void common_cpuidle_devices_uninit(void) +{ + int cpu_id; + struct cpuidle_device *dev; + + for_each_possible_cpu(cpu_id) { + dev = per_cpu_ptr(common_cpuidle_devices, cpu_id); + cpuidle_unregister_device(dev); + } + + free_percpu(common_cpuidle_devices); +} + +/** + * common_cpuidle_init() - Provides some commonly used init functionality. + * @pdrv Pointer to your cpuidle_driver object. + * @simple Use the common simple_enter wrapper? + * @driver_data_init Pointer to your platform function to initialize your + * platform specific driver data. Use NULL if platform + * specific data is not needed. + * + * Common cpuidle init interface to provide common cpuidle functionality + * used by many platforms. + */ +int __init common_cpuidle_init(struct cpuidle_driver *pdrv, bool simple, + void (*driver_data_init)(struct cpuidle_device *dev)) +{ + struct cpuidle_device *dev; + struct cpuidle_driver *drv; + int i, cpu_id, ret; + + if (!pdrv || pdrv->state_count > CPUIDLE_STATE_MAX) { + pr_err("%s: Invalid Input\n", __func__); + return -EINVAL; + } + + drv = kmalloc(sizeof(struct cpuidle_driver), GFP_KERNEL); + if (!drv) { + pr_err("%s: no memory for cpuidle driver\n", __func__); + return -ENOMEM; + } + + *drv = *pdrv; + + for (i = 0; simple && (i < drv->state_count); i++) { + do_idle[i] = drv->states[i].enter; + drv->states[i].enter = simple_enter; + } + + ret = cpuidle_register_driver(drv); + if (ret) { + pr_err("%s: Failed to register cpuidle driver\n", __func__); + goto free_drv; + } + + common_cpuidle_devices = alloc_percpu(struct cpuidle_device); + if (common_cpuidle_devices == NULL) { + ret = -ENOMEM; + goto unregister_drv; + } + + /* initialize state data for each cpuidle_device */ + for_each_possible_cpu(cpu_id) { + dev = per_cpu_ptr(common_cpuidle_devices, cpu_id); + dev->cpu = cpu_id; + dev->state_count = drv->state_count; + + if (driver_data_init) + driver_data_init(dev); + + ret = cpuidle_register_device(dev); + if (ret) { + pr_err("%s: Failed to register cpu %u\n", + __func__, cpu_id); + goto uninit; + } + } + + return 0; +uninit: + + common_cpuidle_devices_uninit(); + +unregister_drv: + + cpuidle_unregister_driver(drv); + +free_drv: + + kfree(drv); + + return ret; +} diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 712abcc..2aa89db 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -56,6 +56,16 @@ struct cpuidle_state { #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) +/* Common ARM WFI state */ +#define CPUIDLE_ARM_WFI_STATE {\ + .enter = cpuidle_def_idle,\ + .exit_latency = 2,\ + .target_residency = 1,\ + .flags = CPUIDLE_FLAG_TIME_VALID,\ + .name = "WFI",\ + .desc = "ARM core clock gating (WFI)",\ +} + /** * cpuidle_get_statedata - retrieves private driver state data * @st_usage: the state usage statistics @@ -141,6 +151,13 @@ extern void cpuidle_resume_and_unlock(void); extern int cpuidle_enable_device(struct cpuidle_device *dev); extern void cpuidle_disable_device(struct cpuidle_device *dev); +/* provide a default idle function */ +extern int cpuidle_def_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index); +extern int common_cpuidle_init(struct cpuidle_driver *drv, bool simple, + void (*driver_data_init)(struct cpuidle_device *dev)); +extern void common_cpuidle_devices_uninit(void); + #else static inline void disable_cpuidle(void) { } static inline int cpuidle_idle_call(void) { return -ENODEV; } @@ -157,6 +174,13 @@ static inline void cpuidle_resume_and_unlock(void) { } static inline int cpuidle_enable_device(struct cpuidle_device *dev) {return -ENODEV; } static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } +static inline int cpuidle_def_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{return -ENODEV; } +static inline int common_cpuidle_init(struct cpuidle_driver *pdrv, + bool simple, void (*driver_data_init)(struct cpuidle_device *dev)) +{return -ENODEV; } +static inline void common_cpuidle_devices_uninit(void) { } #endif -- 1.7.1