diff options
Diffstat (limited to 'drivers/devfreq')
| -rw-r--r-- | drivers/devfreq/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/devfreq/devfreq.c | 273 |
2 files changed, 203 insertions, 75 deletions
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig index defe1d438710..35535833b6f7 100644 --- a/drivers/devfreq/Kconfig +++ b/drivers/devfreq/Kconfig @@ -83,7 +83,6 @@ config ARM_EXYNOS_BUS_DEVFREQ select DEVFREQ_GOV_PASSIVE select DEVFREQ_EVENT_EXYNOS_PPMU select PM_DEVFREQ_EVENT - select PM_OPP help This adds the common DEVFREQ driver for Exynos Memory bus. Exynos Memory bus has one more group of memory bus (e.g, MIF and INT block). @@ -98,7 +97,7 @@ config ARM_TEGRA_DEVFREQ ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \ ARCH_TEGRA_210_SOC || \ COMPILE_TEST - select PM_OPP + depends on COMMON_CLK help This adds the DEVFREQ driver for the Tegra family of SoCs. It reads ACTMON counters of memory controllers and adjusts the @@ -109,7 +108,6 @@ config ARM_TEGRA20_DEVFREQ depends on (TEGRA_MC && TEGRA20_EMC) || COMPILE_TEST depends on COMMON_CLK select DEVFREQ_GOV_SIMPLE_ONDEMAND - select PM_OPP help This adds the DEVFREQ driver for the Tegra20 family of SoCs. It reads Memory Controller counters and adjusts the operating @@ -121,7 +119,6 @@ config ARM_RK3399_DMC_DEVFREQ select DEVFREQ_EVENT_ROCKCHIP_DFI select DEVFREQ_GOV_SIMPLE_ONDEMAND select PM_DEVFREQ_EVENT - select PM_OPP help This adds the DEVFREQ driver for the RK3399 DMC(Dynamic Memory Controller). It sets the frequency for the memory controller and reads the usage counts diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 425149e8bab0..57f6944d65a6 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -24,11 +24,14 @@ #include <linux/printk.h> #include <linux/hrtimer.h> #include <linux/of.h> +#include <linux/pm_qos.h> #include "governor.h" #define CREATE_TRACE_POINTS #include <trace/events/devfreq.h> +#define HZ_PER_KHZ 1000 + static struct class *devfreq_class; /* @@ -99,6 +102,54 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq) } /** + * get_freq_range() - Get the current freq range + * @devfreq: the devfreq instance + * @min_freq: the min frequency + * @max_freq: the max frequency + * + * This takes into consideration all constraints. + */ +static void get_freq_range(struct devfreq *devfreq, + unsigned long *min_freq, + unsigned long *max_freq) +{ + unsigned long *freq_table = devfreq->profile->freq_table; + s32 qos_min_freq, qos_max_freq; + + lockdep_assert_held(&devfreq->lock); + + /* + * Initialize minimum/maximum frequency from freq table. + * The devfreq drivers can initialize this in either ascending or + * descending order and devfreq core supports both. + */ + if (freq_table[0] < freq_table[devfreq->profile->max_state - 1]) { + *min_freq = freq_table[0]; + *max_freq = freq_table[devfreq->profile->max_state - 1]; + } else { + *min_freq = freq_table[devfreq->profile->max_state - 1]; + *max_freq = freq_table[0]; + } + + /* Apply constraints from PM QoS */ + qos_min_freq = dev_pm_qos_read_value(devfreq->dev.parent, + DEV_PM_QOS_MIN_FREQUENCY); + qos_max_freq = dev_pm_qos_read_value(devfreq->dev.parent, + DEV_PM_QOS_MAX_FREQUENCY); + *min_freq = max(*min_freq, (unsigned long)HZ_PER_KHZ * qos_min_freq); + if (qos_max_freq != PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE) + *max_freq = min(*max_freq, + (unsigned long)HZ_PER_KHZ * qos_max_freq); + + /* Apply constraints from OPP interface */ + *min_freq = max(*min_freq, devfreq->scaling_min_freq); + *max_freq = min(*max_freq, devfreq->scaling_max_freq); + + if (*min_freq > *max_freq) + *min_freq = *max_freq; +} + +/** * devfreq_get_freq_level() - Lookup freq_table for the frequency * @devfreq: the devfreq instance * @freq: the target frequency @@ -351,16 +402,7 @@ int update_devfreq(struct devfreq *devfreq) err = devfreq->governor->get_target_freq(devfreq, &freq); if (err) return err; - - /* - * Adjust the frequency with user freq, QoS and available freq. - * - * List from the highest priority - * max_freq - * min_freq - */ - max_freq = min(devfreq->scaling_max_freq, devfreq->max_freq); - min_freq = max(devfreq->scaling_min_freq, devfreq->min_freq); + get_freq_range(devfreq, &min_freq, &max_freq); if (freq < min_freq) { freq = min_freq; @@ -568,26 +610,69 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, void *devp) { struct devfreq *devfreq = container_of(nb, struct devfreq, nb); - int ret; + int err = -EINVAL; mutex_lock(&devfreq->lock); devfreq->scaling_min_freq = find_available_min_freq(devfreq); - if (!devfreq->scaling_min_freq) { - mutex_unlock(&devfreq->lock); - return -EINVAL; - } + if (!devfreq->scaling_min_freq) + goto out; devfreq->scaling_max_freq = find_available_max_freq(devfreq); if (!devfreq->scaling_max_freq) { - mutex_unlock(&devfreq->lock); - return -EINVAL; + devfreq->scaling_max_freq = ULONG_MAX; + goto out; } - ret = update_devfreq(devfreq); + err = update_devfreq(devfreq); + +out: mutex_unlock(&devfreq->lock); + if (err) + dev_err(devfreq->dev.parent, + "failed to update frequency from OPP notifier (%d)\n", + err); - return ret; + return NOTIFY_OK; +} + +/** + * qos_notifier_call() - Common handler for QoS constraints. + * @devfreq: the devfreq instance. + */ +static int qos_notifier_call(struct devfreq *devfreq) +{ + int err; + + mutex_lock(&devfreq->lock); + err = update_devfreq(devfreq); + mutex_unlock(&devfreq->lock); + if (err) + dev_err(devfreq->dev.parent, + "failed to update frequency from PM QoS (%d)\n", + err); + + return NOTIFY_OK; +} + +/** + * qos_min_notifier_call() - Callback for QoS min_freq changes. + * @nb: Should be devfreq->nb_min + */ +static int qos_min_notifier_call(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + return qos_notifier_call(container_of(nb, struct devfreq, nb_min)); +} + +/** + * qos_max_notifier_call() - Callback for QoS max_freq changes. + * @nb: Should be devfreq->nb_max + */ +static int qos_max_notifier_call(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + return qos_notifier_call(container_of(nb, struct devfreq, nb_max)); } /** @@ -599,16 +684,36 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, static void devfreq_dev_release(struct device *dev) { struct devfreq *devfreq = to_devfreq(dev); + int err; mutex_lock(&devfreq_list_lock); - if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { - mutex_unlock(&devfreq_list_lock); - dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); - return; - } list_del(&devfreq->node); mutex_unlock(&devfreq_list_lock); + err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_max, + DEV_PM_QOS_MAX_FREQUENCY); + if (err && err != -ENOENT) + dev_warn(dev->parent, + "Failed to remove max_freq notifier: %d\n", err); + err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_min, + DEV_PM_QOS_MIN_FREQUENCY); + if (err && err != -ENOENT) + dev_warn(dev->parent, + "Failed to remove min_freq notifier: %d\n", err); + + if (dev_pm_qos_request_active(&devfreq->user_max_freq_req)) { + err = dev_pm_qos_remove_request(&devfreq->user_max_freq_req); + if (err) + dev_warn(dev->parent, + "Failed to remove max_freq request: %d\n", err); + } + if (dev_pm_qos_request_active(&devfreq->user_min_freq_req)) { + err = dev_pm_qos_remove_request(&devfreq->user_min_freq_req); + if (err) + dev_warn(dev->parent, + "Failed to remove min_freq request: %d\n", err); + } + if (devfreq->profile->exit) devfreq->profile->exit(devfreq->dev.parent); @@ -660,6 +765,7 @@ struct devfreq *devfreq_add_device(struct device *dev, devfreq->dev.parent = dev; devfreq->dev.class = devfreq_class; devfreq->dev.release = devfreq_dev_release; + INIT_LIST_HEAD(&devfreq->node); devfreq->profile = profile; strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); devfreq->previous_freq = profile->initial_freq; @@ -681,7 +787,6 @@ struct devfreq *devfreq_add_device(struct device *dev, err = -EINVAL; goto err_dev; } - devfreq->min_freq = devfreq->scaling_min_freq; devfreq->scaling_max_freq = find_available_max_freq(devfreq); if (!devfreq->scaling_max_freq) { @@ -689,7 +794,6 @@ struct devfreq *devfreq_add_device(struct device *dev, err = -EINVAL; goto err_dev; } - devfreq->max_freq = devfreq->scaling_max_freq; devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); atomic_set(&devfreq->suspend_count, 0); @@ -730,6 +834,28 @@ struct devfreq *devfreq_add_device(struct device *dev, mutex_unlock(&devfreq->lock); + err = dev_pm_qos_add_request(dev, &devfreq->user_min_freq_req, + DEV_PM_QOS_MIN_FREQUENCY, 0); + if (err < 0) + goto err_devfreq; + err = dev_pm_qos_add_request(dev, &devfreq->user_max_freq_req, + DEV_PM_QOS_MAX_FREQUENCY, + PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE); + if (err < 0) + goto err_devfreq; + + devfreq->nb_min.notifier_call = qos_min_notifier_call; + err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_min, + DEV_PM_QOS_MIN_FREQUENCY); + if (err) + goto err_devfreq; + + devfreq->nb_max.notifier_call = qos_max_notifier_call; + err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_max, + DEV_PM_QOS_MAX_FREQUENCY); + if (err) + goto err_devfreq; + mutex_lock(&devfreq_list_lock); governor = try_then_request_governor(devfreq->governor_name); @@ -1303,41 +1429,37 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, unsigned long value; int ret; + /* + * Protect against theoretical sysfs writes between + * device_add and dev_pm_qos_add_request + */ + if (!dev_pm_qos_request_active(&df->user_min_freq_req)) + return -EAGAIN; + ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; - mutex_lock(&df->lock); - - if (value) { - if (value > df->max_freq) { - ret = -EINVAL; - goto unlock; - } - } else { - unsigned long *freq_table = df->profile->freq_table; - - /* Get minimum frequency according to sorting order */ - if (freq_table[0] < freq_table[df->profile->max_state - 1]) - value = freq_table[0]; - else - value = freq_table[df->profile->max_state - 1]; - } + /* Round down to kHz for PM QoS */ + ret = dev_pm_qos_update_request(&df->user_min_freq_req, + value / HZ_PER_KHZ); + if (ret < 0) + return ret; - df->min_freq = value; - update_devfreq(df); - ret = count; -unlock: - mutex_unlock(&df->lock); - return ret; + return count; } static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(dev); + unsigned long min_freq, max_freq; - return sprintf(buf, "%lu\n", max(df->scaling_min_freq, df->min_freq)); + mutex_lock(&df->lock); + get_freq_range(df, &min_freq, &max_freq); + mutex_unlock(&df->lock); + + return sprintf(buf, "%lu\n", min_freq); } static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, @@ -1347,33 +1469,37 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, unsigned long value; int ret; + /* + * Protect against theoretical sysfs writes between + * device_add and dev_pm_qos_add_request + */ + if (!dev_pm_qos_request_active(&df->user_max_freq_req)) + return -EINVAL; + ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; - mutex_lock(&df->lock); - - if (value) { - if (value < df->min_freq) { - ret = -EINVAL; - goto unlock; - } - } else { - unsigned long *freq_table = df->profile->freq_table; + /* + * PM QoS frequencies are in kHz so we need to convert. Convert by + * rounding upwards so that the acceptable interval never shrinks. + * + * For example if the user writes "666666666" to sysfs this value will + * be converted to 666667 kHz and back to 666667000 Hz before an OPP + * lookup, this ensures that an OPP of 666666666Hz is still accepted. + * + * A value of zero means "no limit". + */ + if (value) + value = DIV_ROUND_UP(value, HZ_PER_KHZ); + else + value = PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE; - /* Get maximum frequency according to sorting order */ - if (freq_table[0] < freq_table[df->profile->max_state - 1]) - value = freq_table[df->profile->max_state - 1]; - else - value = freq_table[0]; - } + ret = dev_pm_qos_update_request(&df->user_max_freq_req, value); + if (ret < 0) + return ret; - df->max_freq = value; - update_devfreq(df); - ret = count; -unlock: - mutex_unlock(&df->lock); - return ret; + return count; } static DEVICE_ATTR_RW(min_freq); @@ -1381,8 +1507,13 @@ static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(dev); + unsigned long min_freq, max_freq; + + mutex_lock(&df->lock); + get_freq_range(df, &min_freq, &max_freq); + mutex_unlock(&df->lock); - return sprintf(buf, "%lu\n", min(df->scaling_max_freq, df->max_freq)); + return sprintf(buf, "%lu\n", max_freq); } static DEVICE_ATTR_RW(max_freq); |