diff options
Diffstat (limited to 'arch/arm/mach-ux500/pm/prcmu-qos-power.c')
| -rw-r--r-- | arch/arm/mach-ux500/pm/prcmu-qos-power.c | 722 |
1 files changed, 722 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/pm/prcmu-qos-power.c b/arch/arm/mach-ux500/pm/prcmu-qos-power.c new file mode 100644 index 00000000000..a600a57dc13 --- /dev/null +++ b/arch/arm/mach-ux500/pm/prcmu-qos-power.c @@ -0,0 +1,722 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * License Terms: GNU General Public License v2 + * Author: Martin Persson + * Per Fransson <per.xx.fransson@stericsson.com> + * + * Quality of Service for the U8500 PRCM Unit interface driver + * + * Strongly influenced by kernel/pm_qos_params.c. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/uaccess.h> +#include <linux/cpufreq.h> +#include <linux/mfd/dbx500-prcmu.h> +#include <linux/cpufreq-dbx500.h> + +#include <mach/prcmu-debug.h> + +#define ARM_THRESHOLD_FREQ (400000) + +static int qos_delayed_cpufreq_notifier(struct notifier_block *, + unsigned long, void *); + +static s32 cpufreq_requirement_queued; +static s32 cpufreq_requirement_set; + +/* + * locking rule: all changes to requirements or prcmu_qos_object list + * and prcmu_qos_objects need to happen with prcmu_qos_lock + * held, taken with _irqsave. One lock to rule them all + */ +struct requirement_list { + struct list_head list; + union { + s32 value; + s32 usec; + s32 kbps; + }; + char *name; +}; + +static s32 max_compare(s32 v1, s32 v2); + +struct prcmu_qos_object { + struct requirement_list requirements; + struct blocking_notifier_head *notifiers; + struct miscdevice prcmu_qos_power_miscdev; + char *name; + s32 default_value; + s32 force_value; + atomic_t target_value; + s32 (*comparitor)(s32, s32); +}; + +static struct prcmu_qos_object null_qos; +static BLOCKING_NOTIFIER_HEAD(prcmu_ape_opp_notifier); +static BLOCKING_NOTIFIER_HEAD(prcmu_ddr_opp_notifier); + +static struct prcmu_qos_object ape_opp_qos = { + .requirements = { + LIST_HEAD_INIT(ape_opp_qos.requirements.list) + }, + .notifiers = &prcmu_ape_opp_notifier, + .name = "ape_opp", + /* Target value in % APE OPP */ + .default_value = 50, + .force_value = 0, + .target_value = ATOMIC_INIT(50), + .comparitor = max_compare +}; + +static struct prcmu_qos_object ddr_opp_qos = { + .requirements = { + LIST_HEAD_INIT(ddr_opp_qos.requirements.list) + }, + .notifiers = &prcmu_ddr_opp_notifier, + .name = "ddr_opp", + /* Target value in % DDR OPP */ + .default_value = 25, + .force_value = 0, + .target_value = ATOMIC_INIT(25), + .comparitor = max_compare +}; + +static struct prcmu_qos_object arm_opp_qos = { + .requirements = { + LIST_HEAD_INIT(arm_opp_qos.requirements.list) + }, + /* + * No notifier on ARM opp qos request, since this won't actually + * do anything, except changing limits for cpufreq + */ + .name = "arm_opp", + /* Target value in % ARM OPP, note can be 125% */ + .default_value = 25, + .force_value = 0, + .target_value = ATOMIC_INIT(25), + .comparitor = max_compare +}; + +static struct prcmu_qos_object *prcmu_qos_array[] = { + &null_qos, + &ape_opp_qos, + &ddr_opp_qos, + &arm_opp_qos, +}; + +static DEFINE_MUTEX(prcmu_qos_mutex); +static DEFINE_SPINLOCK(prcmu_qos_lock); + +static bool ape_opp_forced_to_50_partly_25; + +static unsigned long cpufreq_opp_delay = HZ / 5; + +unsigned long prcmu_qos_get_cpufreq_opp_delay(void) +{ + return cpufreq_opp_delay; +} + +static struct notifier_block qos_delayed_cpufreq_notifier_block = { + .notifier_call = qos_delayed_cpufreq_notifier, +}; + +void prcmu_qos_set_cpufreq_opp_delay(unsigned long n) +{ + if (n == 0) { + cpufreq_unregister_notifier(&qos_delayed_cpufreq_notifier_block, + CPUFREQ_TRANSITION_NOTIFIER); + prcmu_qos_update_requirement(PRCMU_QOS_DDR_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + prcmu_qos_update_requirement(PRCMU_QOS_APE_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + cpufreq_requirement_set = PRCMU_QOS_DEFAULT_VALUE; + cpufreq_requirement_queued = PRCMU_QOS_DEFAULT_VALUE; + } else if (cpufreq_opp_delay != 0) { + cpufreq_register_notifier(&qos_delayed_cpufreq_notifier_block, + CPUFREQ_TRANSITION_NOTIFIER); + } + cpufreq_opp_delay = n; +} +#ifdef CONFIG_CPU_FREQ +static void update_cpu_limits(s32 extreme_value) +{ + int cpu; + struct cpufreq_policy policy; + int ret; + int min_freq, max_freq; + + for_each_online_cpu(cpu) { + ret = cpufreq_get_policy(&policy, cpu); + if (ret) { + pr_err("prcmu qos: get cpufreq policy failed (cpu%d)\n", + cpu); + continue; + } + + ret = dbx500_cpufreq_get_limits(cpu, extreme_value, + &min_freq, &max_freq); + if (ret) + continue; + /* + * cpufreq fw does not allow frequency change if + * "current min freq" > "new max freq" or + * "current max freq" < "new min freq". + * Thus the intermediate steps below. + */ + if (policy.min > max_freq) { + ret = cpufreq_update_freq(cpu, min_freq, policy.max); + if (ret) + pr_err("prcmu qos: update min cpufreq failed (1)\n"); + } + if (policy.max < min_freq) { + ret = cpufreq_update_freq(cpu, policy.min, max_freq); + if (ret) + pr_err("prcmu qos: update max cpufreq failed (2)\n"); + } + + ret = cpufreq_update_freq(cpu, min_freq, max_freq); + if (ret) + pr_err("prcmu qos: update max cpufreq failed (3)\n"); + } + +} +#else +static inline void update_cpu_limits(s32 extreme_value) { } +#endif +/* static helper function */ +static s32 max_compare(s32 v1, s32 v2) +{ + return max(v1, v2); +} + +static void update_target(int target) +{ + s32 extreme_value; + struct requirement_list *node; + unsigned long flags; + bool update = false; + u8 op; + + mutex_lock(&prcmu_qos_mutex); + + spin_lock_irqsave(&prcmu_qos_lock, flags); + extreme_value = prcmu_qos_array[target]->default_value; + + if (prcmu_qos_array[target]->force_value != 0) { + extreme_value = prcmu_qos_array[target]->force_value; + update = true; + } else { + list_for_each_entry(node, + &prcmu_qos_array[target]->requirements.list, + list) { + extreme_value = prcmu_qos_array[target]->comparitor( + extreme_value, node->value); + } + if (atomic_read(&prcmu_qos_array[target]->target_value) + != extreme_value) { + update = true; + atomic_set(&prcmu_qos_array[target]->target_value, + extreme_value); + pr_debug("prcmu qos: new target for qos %d is %d\n", + target, atomic_read( + &prcmu_qos_array[target]->target_value + )); + } + } + + spin_unlock_irqrestore(&prcmu_qos_lock, flags); + + if (!update) + goto unlock_and_return; + + if (prcmu_qos_array[target]->notifiers) + blocking_notifier_call_chain(prcmu_qos_array[target]->notifiers, + (unsigned long)extreme_value, + NULL); + switch (target) { + case PRCMU_QOS_DDR_OPP: + switch (extreme_value) { + case 50: + op = DDR_50_OPP; + pr_debug("prcmu qos: set ddr opp to 50%%\n"); + break; + case 100: + op = DDR_100_OPP; + pr_debug("prcmu qos: set ddr opp to 100%%\n"); + break; + case 25: + /* 25% DDR OPP is not supported on 5500 */ + if (!cpu_is_u5500()) { + op = DDR_25_OPP; + pr_debug("prcmu qos: set ddr opp to 25%%\n"); + break; + } + default: + pr_err("prcmu qos: Incorrect ddr target value (%d)", + extreme_value); + goto unlock_and_return; + } + prcmu_set_ddr_opp(op); + prcmu_debug_ddr_opp_log(op); + break; + case PRCMU_QOS_APE_OPP: + switch (extreme_value) { + case 50: + op = APE_50_OPP; + pr_debug("prcmu qos: set ape opp to 50%%\n"); + break; + case 100: + op = APE_100_OPP; + pr_debug("prcmu qos: set ape opp to 100%%\n"); + break; + default: + pr_err("prcmu qos: Incorrect ape target value (%d)", + extreme_value); + goto unlock_and_return; + } + + if (!ape_opp_forced_to_50_partly_25) + (void)prcmu_set_ape_opp(op); + prcmu_debug_ape_opp_log(op); + break; + case PRCMU_QOS_ARM_OPP: + { + mutex_unlock(&prcmu_qos_mutex); + /* + * We can't hold the mutex since changing cpufreq + * will trigger an prcmu fw callback. + */ + update_cpu_limits(extreme_value); + /* Return since the lock is unlocked */ + return; + + break; + } + default: + pr_err("prcmu qos: Incorrect target\n"); + break; + } + +unlock_and_return: + mutex_unlock(&prcmu_qos_mutex); +} + +void prcmu_qos_force_opp(int prcmu_qos_class, s32 i) +{ + prcmu_qos_array[prcmu_qos_class]->force_value = i; + update_target(prcmu_qos_class); +} + +void prcmu_qos_voice_call_override(bool enable) +{ + u8 op; + + mutex_lock(&prcmu_qos_mutex); + + ape_opp_forced_to_50_partly_25 = enable; + + if (enable) { + (void)prcmu_set_ape_opp(APE_50_PARTLY_25_OPP); + goto unlock_and_return; + } + + /* Disable: set the OPP according to the current target value. */ + switch (atomic_read( + &prcmu_qos_array[PRCMU_QOS_APE_OPP]->target_value)) { + case 50: + op = APE_50_OPP; + break; + case 100: + op = APE_100_OPP; + break; + default: + goto unlock_and_return; + } + + (void)prcmu_set_ape_opp(op); + +unlock_and_return: + mutex_unlock(&prcmu_qos_mutex); +} + +/** + * prcmu_qos_requirement - returns current prcmu qos expectation + * @prcmu_qos_class: identification of which qos value is requested + * + * This function returns the current target value in an atomic manner. + */ +int prcmu_qos_requirement(int prcmu_qos_class) +{ + return atomic_read(&prcmu_qos_array[prcmu_qos_class]->target_value); +} +EXPORT_SYMBOL_GPL(prcmu_qos_requirement); + +/** + * prcmu_qos_add_requirement - inserts new qos request into the list + * @prcmu_qos_class: identifies which list of qos request to us + * @name: identifies the request + * @value: defines the qos request + * + * This function inserts a new entry in the prcmu_qos_class list of requested + * qos performance characteristics. It recomputes the aggregate QoS + * expectations for the prcmu_qos_class of parameters. + */ +int prcmu_qos_add_requirement(int prcmu_qos_class, char *name, s32 value) +{ + struct requirement_list *dep; + unsigned long flags; + + dep = kzalloc(sizeof(struct requirement_list), GFP_KERNEL); + if (dep == NULL) + return -ENOMEM; + + if (value == PRCMU_QOS_DEFAULT_VALUE) + dep->value = prcmu_qos_array[prcmu_qos_class]->default_value; + else + dep->value = value; + dep->name = kstrdup(name, GFP_KERNEL); + if (!dep->name) + goto cleanup; + + spin_lock_irqsave(&prcmu_qos_lock, flags); + list_add(&dep->list, + &prcmu_qos_array[prcmu_qos_class]->requirements.list); + spin_unlock_irqrestore(&prcmu_qos_lock, flags); + update_target(prcmu_qos_class); + + return 0; + +cleanup: + kfree(dep); + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(prcmu_qos_add_requirement); + +/** + * prcmu_qos_update_requirement - modifies an existing qos request + * @prcmu_qos_class: identifies which list of qos request to us + * @name: identifies the request + * @value: defines the qos request + * + * Updates an existing qos requirement for the prcmu_qos_class of parameters + * along with updating the target prcmu_qos_class value. + * + * If the named request isn't in the list then no change is made. + */ +int prcmu_qos_update_requirement(int prcmu_qos_class, char *name, s32 new_value) +{ + unsigned long flags; + struct requirement_list *node; + int pending_update = 0; + + spin_lock_irqsave(&prcmu_qos_lock, flags); + list_for_each_entry(node, + &prcmu_qos_array[prcmu_qos_class]->requirements.list, list) { + if (strcmp(node->name, name) == 0) { + if (new_value == PRCMU_QOS_DEFAULT_VALUE) + node->value = + prcmu_qos_array[prcmu_qos_class]->default_value; + else + node->value = new_value; + pending_update = 1; + break; + } + } + spin_unlock_irqrestore(&prcmu_qos_lock, flags); + if (pending_update) + update_target(prcmu_qos_class); + + return 0; +} +EXPORT_SYMBOL_GPL(prcmu_qos_update_requirement); + +/** + * prcmu_qos_remove_requirement - modifies an existing qos request + * @prcmu_qos_class: identifies which list of qos request to us + * @name: identifies the request + * + * Will remove named qos request from prcmu_qos_class list of parameters and + * recompute the current target value for the prcmu_qos_class. + */ +void prcmu_qos_remove_requirement(int prcmu_qos_class, char *name) +{ + unsigned long flags; + struct requirement_list *node; + int pending_update = 0; + + spin_lock_irqsave(&prcmu_qos_lock, flags); + list_for_each_entry(node, + &prcmu_qos_array[prcmu_qos_class]->requirements.list, list) { + if (strcmp(node->name, name) == 0) { + kfree(node->name); + list_del(&node->list); + kfree(node); + pending_update = 1; + break; + } + } + spin_unlock_irqrestore(&prcmu_qos_lock, flags); + if (pending_update) + update_target(prcmu_qos_class); +} +EXPORT_SYMBOL_GPL(prcmu_qos_remove_requirement); + +/** + * prcmu_qos_add_notifier - sets notification entry for changes to target value + * @prcmu_qos_class: identifies which qos target changes should be notified. + * @notifier: notifier block managed by caller. + * + * will register the notifier into a notification chain that gets called + * upon changes to the prcmu_qos_class target value. + */ +int prcmu_qos_add_notifier(int prcmu_qos_class, struct notifier_block *notifier) +{ + int retval = -EINVAL; + + if (prcmu_qos_array[prcmu_qos_class]->notifiers) + retval = blocking_notifier_chain_register( + prcmu_qos_array[prcmu_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(prcmu_qos_add_notifier); + +/** + * prcmu_qos_remove_notifier - deletes notification entry from chain. + * @prcmu_qos_class: identifies which qos target changes are notified. + * @notifier: notifier block to be removed. + * + * will remove the notifier from the notification chain that gets called + * upon changes to the prcmu_qos_class target value. + */ +int prcmu_qos_remove_notifier(int prcmu_qos_class, + struct notifier_block *notifier) +{ + int retval = -EINVAL; + if (prcmu_qos_array[prcmu_qos_class]->notifiers) + retval = blocking_notifier_chain_unregister( + prcmu_qos_array[prcmu_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(prcmu_qos_remove_notifier); + +#define USER_QOS_NAME_LEN 32 + +static int prcmu_qos_power_open(struct inode *inode, struct file *filp, + long prcmu_qos_class) +{ + int ret; + char name[USER_QOS_NAME_LEN]; + + filp->private_data = (void *)prcmu_qos_class; + snprintf(name, USER_QOS_NAME_LEN, "file_%08x", (unsigned int)filp); + ret = prcmu_qos_add_requirement(prcmu_qos_class, name, + PRCMU_QOS_DEFAULT_VALUE); + if (ret >= 0) + return 0; + + return -EPERM; +} + + +static int prcmu_qos_ape_power_open(struct inode *inode, struct file *filp) +{ + return prcmu_qos_power_open(inode, filp, PRCMU_QOS_APE_OPP); +} + +static int prcmu_qos_ddr_power_open(struct inode *inode, struct file *filp) +{ + return prcmu_qos_power_open(inode, filp, PRCMU_QOS_DDR_OPP); +} + +static int prcmu_qos_arm_power_open(struct inode *inode, struct file *filp) +{ + return prcmu_qos_power_open(inode, filp, PRCMU_QOS_ARM_OPP); +} + +static int prcmu_qos_power_release(struct inode *inode, struct file *filp) +{ + int prcmu_qos_class; + char name[USER_QOS_NAME_LEN]; + + prcmu_qos_class = (long)filp->private_data; + snprintf(name, USER_QOS_NAME_LEN, "file_%08x", (unsigned int)filp); + prcmu_qos_remove_requirement(prcmu_qos_class, name); + + return 0; +} + +static ssize_t prcmu_qos_power_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + s32 value; + int prcmu_qos_class; + char name[USER_QOS_NAME_LEN]; + + prcmu_qos_class = (long)filp->private_data; + if (count != sizeof(s32)) + return -EINVAL; + if (copy_from_user(&value, buf, sizeof(s32))) + return -EFAULT; + snprintf(name, USER_QOS_NAME_LEN, "file_%08x", (unsigned int)filp); + prcmu_qos_update_requirement(prcmu_qos_class, name, value); + + return sizeof(s32); +} + +/* Functions to provide QoS to user space */ +static const struct file_operations prcmu_qos_ape_power_fops = { + .write = prcmu_qos_power_write, + .open = prcmu_qos_ape_power_open, + .release = prcmu_qos_power_release, +}; + +/* Functions to provide QoS to user space */ +static const struct file_operations prcmu_qos_ddr_power_fops = { + .write = prcmu_qos_power_write, + .open = prcmu_qos_ddr_power_open, + .release = prcmu_qos_power_release, +}; + +static const struct file_operations prcmu_qos_arm_power_fops = { + .write = prcmu_qos_power_write, + .open = prcmu_qos_arm_power_open, + .release = prcmu_qos_power_release, +}; + +static int register_prcmu_qos_misc(struct prcmu_qos_object *qos, + const struct file_operations *fops) +{ + qos->prcmu_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; + qos->prcmu_qos_power_miscdev.name = qos->name; + qos->prcmu_qos_power_miscdev.fops = fops; + + return misc_register(&qos->prcmu_qos_power_miscdev); +} + +static void qos_delayed_work_up_fn(struct work_struct *work) +{ + prcmu_qos_update_requirement(PRCMU_QOS_DDR_OPP, "cpufreq", 100); + prcmu_qos_update_requirement(PRCMU_QOS_APE_OPP, "cpufreq", 100); + cpufreq_requirement_set = 100; +} + +static void qos_delayed_work_down_fn(struct work_struct *work) +{ + prcmu_qos_update_requirement(PRCMU_QOS_DDR_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + prcmu_qos_update_requirement(PRCMU_QOS_APE_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + cpufreq_requirement_set = PRCMU_QOS_DEFAULT_VALUE; +} + +static DECLARE_DELAYED_WORK(qos_delayed_work_up, qos_delayed_work_up_fn); +static DECLARE_DELAYED_WORK(qos_delayed_work_down, qos_delayed_work_down_fn); + +static int qos_delayed_cpufreq_notifier(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct cpufreq_freqs *freq = data; + s32 new_ddr_target; + + /* Only react once per transition and only for one core, e.g. core 0 */ + if (event != CPUFREQ_POSTCHANGE || freq->cpu != 0) + return 0; + + /* + * APE and DDR OPP are always handled together in this solution. + * Hence no need to check both DDR and APE opp in the code below. + */ + + /* Which DDR OPP are we aiming for? */ + if (freq->new > ARM_THRESHOLD_FREQ) + new_ddr_target = 100; + else + new_ddr_target = PRCMU_QOS_DEFAULT_VALUE; + + if (new_ddr_target == cpufreq_requirement_queued) { + /* + * We're already at, or going to, the target requirement. + * This is only a fluctuation within the interval + * corresponding to the same DDR requirement. + */ + return 0; + } + cpufreq_requirement_queued = new_ddr_target; + + if (freq->new > ARM_THRESHOLD_FREQ) { + cancel_delayed_work_sync(&qos_delayed_work_down); + /* + * Only schedule this requirement if it is not the current + * one. + */ + if (new_ddr_target != cpufreq_requirement_set) + schedule_delayed_work(&qos_delayed_work_up, + cpufreq_opp_delay); + } else { + cancel_delayed_work_sync(&qos_delayed_work_up); + /* + * Only schedule this requirement if it is not the current + * one. + */ + if (new_ddr_target != cpufreq_requirement_set) + schedule_delayed_work(&qos_delayed_work_down, + cpufreq_opp_delay); + } + + return 0; +} + +static int __init prcmu_qos_power_init(void) +{ + int ret; + + /* 25% DDR OPP is not supported on u5500 */ + if (cpu_is_u5500()) { + ddr_opp_qos.default_value = 50; + atomic_set(&ddr_opp_qos.target_value, 50); + } + + ret = register_prcmu_qos_misc(&ape_opp_qos, &prcmu_qos_ape_power_fops); + if (ret < 0) { + pr_err("prcmu ape qos: setup failed\n"); + return ret; + } + + ret = register_prcmu_qos_misc(&ddr_opp_qos, &prcmu_qos_ddr_power_fops); + if (ret < 0) { + pr_err("prcmu ddr qos: setup failed\n"); + return ret; + } + + ret = register_prcmu_qos_misc(&arm_opp_qos, &prcmu_qos_arm_power_fops); + if (ret < 0) { + pr_err("prcmu arm qos: setup failed\n"); + return ret; + } + + prcmu_qos_add_requirement(PRCMU_QOS_DDR_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP, "cpufreq", + PRCMU_QOS_DEFAULT_VALUE); + cpufreq_requirement_set = PRCMU_QOS_DEFAULT_VALUE; + cpufreq_requirement_queued = PRCMU_QOS_DEFAULT_VALUE; + + cpufreq_register_notifier(&qos_delayed_cpufreq_notifier_block, + CPUFREQ_TRANSITION_NOTIFIER); + + return ret; +} + +late_initcall(prcmu_qos_power_init); |