diff options
| -rw-r--r-- | drivers/base/power/domain.c | 111 | ||||
| -rw-r--r-- | include/linux/pm_domain.h | 10 |
2 files changed, 110 insertions, 11 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 4194012cdf86..aac656a889dc 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -74,11 +74,70 @@ static const struct genpd_lock_ops genpd_mtx_ops = { .unlock = genpd_unlock_mtx, }; +static void genpd_lock_spin(struct generic_pm_domain *genpd) + __acquires(&genpd->slock) +{ + unsigned long flags; + + spin_lock_irqsave(&genpd->slock, flags); + genpd->lock_flags = flags; +} + +static void genpd_lock_nested_spin(struct generic_pm_domain *genpd, + int depth) + __acquires(&genpd->slock) +{ + unsigned long flags; + + spin_lock_irqsave_nested(&genpd->slock, flags, depth); + genpd->lock_flags = flags; +} + +static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd) + __acquires(&genpd->slock) +{ + unsigned long flags; + + spin_lock_irqsave(&genpd->slock, flags); + genpd->lock_flags = flags; + return 0; +} + +static void genpd_unlock_spin(struct generic_pm_domain *genpd) + __releases(&genpd->slock) +{ + spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags); +} + +static const struct genpd_lock_ops genpd_spin_ops = { + .lock = genpd_lock_spin, + .lock_nested = genpd_lock_nested_spin, + .lock_interruptible = genpd_lock_interruptible_spin, + .unlock = genpd_unlock_spin, +}; + #define genpd_lock(p) p->lock_ops->lock(p) #define genpd_lock_nested(p, d) p->lock_ops->lock_nested(p, d) #define genpd_lock_interruptible(p) p->lock_ops->lock_interruptible(p) #define genpd_unlock(p) p->lock_ops->unlock(p) +#define genpd_is_irq_safe(genpd) (genpd->flags & GENPD_FLAG_IRQ_SAFE) + +static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev, + struct generic_pm_domain *genpd) +{ + bool ret; + + ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd); + + /* Warn once for each IRQ safe dev in no sleep domain */ + if (ret) + dev_warn_once(dev, "PM domain %s will not be powered off\n", + genpd->name); + + return ret; +} + /* * Get the generic PM domain for a particular struct device. * This validates the struct device pointer, the PM domain pointer, @@ -343,7 +402,12 @@ static int genpd_poweroff(struct generic_pm_domain *genpd, bool is_async) if (stat > PM_QOS_FLAGS_NONE) return -EBUSY; - if (!pm_runtime_suspended(pdd->dev) || pdd->dev->power.irq_safe) + /* + * Do not allow PM domain to be powered off, when an IRQ safe + * device is part of a non-IRQ safe domain. + */ + if (!pm_runtime_suspended(pdd->dev) || + irq_safe_dev_in_no_sleep_domain(pdd->dev, genpd)) not_suspended++; } @@ -506,10 +570,10 @@ static int genpd_runtime_suspend(struct device *dev) } /* - * If power.irq_safe is set, this routine will be run with interrupts - * off, so it can't use mutexes. + * If power.irq_safe is set, this routine may be run with + * IRQs disabled, so suspend only if the PM domain also is irq_safe. */ - if (dev->power.irq_safe) + if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) return 0; genpd_lock(genpd); @@ -543,8 +607,11 @@ static int genpd_runtime_resume(struct device *dev) if (IS_ERR(genpd)) return -EINVAL; - /* If power.irq_safe, the PM domain is never powered off. */ - if (dev->power.irq_safe) { + /* + * As we don't power off a non IRQ safe domain, which holds + * an IRQ safe device, we don't need to restore power to it. + */ + if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) { timed = false; goto out; } @@ -586,7 +653,8 @@ static int genpd_runtime_resume(struct device *dev) err_stop: genpd_stop_dev(genpd, dev); err_poweroff: - if (!dev->power.irq_safe) { + if (!pm_runtime_is_irq_safe(dev) || + (pm_runtime_is_irq_safe(dev) && genpd_is_irq_safe(genpd))) { genpd_lock(genpd); genpd_poweroff(genpd, 0); genpd_unlock(genpd); @@ -1223,6 +1291,17 @@ static int genpd_add_subdomain(struct generic_pm_domain *genpd, || genpd == subdomain) return -EINVAL; + /* + * If the domain can be powered on/off in an IRQ safe + * context, ensure that the subdomain can also be + * powered on/off in that context. + */ + if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) { + WARN("Parent %s of subdomain %s must be IRQ safe\n", + genpd->name, subdomain->name); + return -EINVAL; + } + link = kzalloc(sizeof(*link), GFP_KERNEL); if (!link) return -ENOMEM; @@ -1337,6 +1416,17 @@ static int genpd_set_default_power_state(struct generic_pm_domain *genpd) return 0; } +static void genpd_lock_init(struct generic_pm_domain *genpd) +{ + if (genpd->flags & GENPD_FLAG_IRQ_SAFE) { + spin_lock_init(&genpd->slock); + genpd->lock_ops = &genpd_spin_ops; + } else { + mutex_init(&genpd->mlock); + genpd->lock_ops = &genpd_mtx_ops; + } +} + /** * pm_genpd_init - Initialize a generic I/O PM domain object. * @genpd: PM domain object to initialize. @@ -1356,8 +1446,7 @@ int pm_genpd_init(struct generic_pm_domain *genpd, INIT_LIST_HEAD(&genpd->master_links); INIT_LIST_HEAD(&genpd->slave_links); INIT_LIST_HEAD(&genpd->dev_list); - mutex_init(&genpd->mlock); - genpd->lock_ops = &genpd_mtx_ops; + genpd_lock_init(genpd); genpd->gov = gov; INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn); atomic_set(&genpd->sd_count, 0); @@ -2131,7 +2220,9 @@ static int pm_genpd_summary_one(struct seq_file *s, } list_for_each_entry(pm_data, &genpd->dev_list, list_node) { - kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL); + kobj_path = kobject_get_path(&pm_data->dev->kobj, + genpd_is_irq_safe(genpd) ? + GFP_ATOMIC : GFP_KERNEL); if (kobj_path == NULL) continue; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 811b968eb740..81ece61075df 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -15,9 +15,11 @@ #include <linux/err.h> #include <linux/of.h> #include <linux/notifier.h> +#include <linux/spinlock.h> /* Defines used for the flags field in the struct generic_pm_domain */ #define GENPD_FLAG_PM_CLK (1U << 0) /* PM domain uses PM clk */ +#define GENPD_FLAG_IRQ_SAFE (1U << 1) /* PM domain operates in atomic */ enum gpd_status { GPD_STATE_ACTIVE = 0, /* PM domain is active */ @@ -76,7 +78,13 @@ struct generic_pm_domain { unsigned int state_idx; /* state that genpd will go to when off */ void *free; /* Free the state that was allocated for default */ const struct genpd_lock_ops *lock_ops; - struct mutex mlock; + union { + struct mutex mlock; + struct { + spinlock_t slock; + unsigned long lock_flags; + }; + }; }; |