| Message ID | 20180620172226.15012-6-ulf.hansson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | PM / Domains: Support hierarchical CPU arrangement (PSCI/ARM) | expand |
On Wednesday, June 20, 2018 7:22:05 PM CEST Ulf Hansson wrote: > Introduce two new genpd helper functions, of_genpd_attach|detach_cpu(), > which takes the CPU-number as an in-parameter. > > To attach a CPU to a genpd, of_genpd_attach_cpu() starts by fetching the > struct device belonging to the CPU. Then it calls genpd_dev_pm_attach(), > which via DT tries to hook up the CPU device to its corresponding PM > domain. If it succeeds, of_genpd_attach_cpu() continues to prepare/enable > runtime PM of the device. > > To detach a CPU from its PM domain, of_genpd_attach_cpu() reverse the > operations made from of_genpd_attach_cpu(). However, first it checks that > the CPU device has a valid PM domain pointer assigned, as to make sure it > belongs to genpd. > > Cc: Lina Iyer <ilina@codeaurora.org> > Co-developed-by: Lina Iyer <lina.iyer@linaro.org> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > --- > drivers/base/power/domain.c | 69 +++++++++++++++++++++++++++++++++++++ > include/linux/pm_domain.h | 9 +++++ > 2 files changed, 78 insertions(+) > > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index 6149ce0bfa7b..299fa2febbec 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -2445,6 +2445,75 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev, > } > EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id); > > +/* > + * of_genpd_attach_cpu() - Attach a CPU to its PM domain > + * @cpu: The CPU to be attached. > + * > + * Parses the OF node of the CPU's device, to find a PM domain specifier. If > + * such is found, attaches the CPU's device to the retrieved pm_domain ops and > + * enables runtime PM for it. This to allow the CPU to be power managed through > + * its PM domain. > + * > + * Returns zero when successfully attached the CPU's device to its PM domain, > + * else a negative error code. > + */ > +int of_genpd_attach_cpu(int cpu) > +{ > + struct device *dev = get_cpu_device(cpu); > + int ret; > + > + if (!dev) { > + pr_warn("genpd: no dev for cpu%d\n", cpu); > + return -ENODEV; > + } I'm not sure about the value of the above. Is it possible even? > + > + ret = genpd_dev_pm_attach(dev); > + if (ret != 1) { > + dev_warn(dev, "genpd: attach cpu failed %d\n", ret); This looks like a debug message. Do you really want to print it with high prio? > + return ret < 0 ? ret : -ENODEV; > + } > + > + pm_runtime_irq_safe(dev); > + pm_runtime_get_noresume(dev); > + pm_runtime_set_active(dev); > + pm_runtime_enable(dev); > + > + dev_info(dev, "genpd: attached cpu\n"); This definitely is a debug message. > + return 0; > +} > +EXPORT_SYMBOL(of_genpd_attach_cpu); > + > +/** > + * of_genpd_detach_cpu() - Detach a CPU from its PM domain > + * @cpu: The CPU to be detached. > + * > + * Detach the CPU's device from its corresponding PM domain. If detaching is > + * completed successfully, disable runtime PM and restore the runtime PM usage > + * count for the CPU's device. > + */ > +void of_genpd_detach_cpu(int cpu) > +{ > + struct device *dev = get_cpu_device(cpu); > + > + if (!dev) { > + pr_warn("genpd: no dev for cpu%d\n", cpu); > + return; > + } > + > + /* Check that the device is attached to a genpd. */ > + if (!(dev->pm_domain && dev->pm_domain->detach == genpd_dev_pm_detach)) > + return; > + > + genpd_dev_pm_detach(dev, true); > + > + pm_runtime_disable(dev); > + pm_runtime_put_noidle(dev); > + pm_runtime_reinit(dev); > + > + dev_info(dev, "genpd: detached cpu\n"); > +} > +EXPORT_SYMBOL(of_genpd_detach_cpu); > + > static const struct of_device_id idle_state_match[] = { > { .compatible = "domain-idle-state", }, > { } > diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h > index 3f67ff0c1c69..2c09cf80b285 100644 > --- a/include/linux/pm_domain.h > +++ b/include/linux/pm_domain.h > @@ -243,6 +243,8 @@ unsigned int of_genpd_opp_to_performance_state(struct device *dev, > int genpd_dev_pm_attach(struct device *dev); > struct device *genpd_dev_pm_attach_by_id(struct device *dev, > unsigned int index); > +int of_genpd_attach_cpu(int cpu); > +void of_genpd_detach_cpu(int cpu); > #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ > static inline int of_genpd_add_provider_simple(struct device_node *np, > struct generic_pm_domain *genpd) > @@ -294,6 +296,13 @@ static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev, > return NULL; > } > > +static inline int of_genpd_attach_cpu(int cpu) > +{ > + return -ENODEV; > +} > + > +static inline void of_genpd_detach_cpu(int cpu) {} > + > static inline > struct generic_pm_domain *of_genpd_remove_last(struct device_node *np) > { > I'd combine this with patch [04/26]. The split here is somewhat artificial IMO.
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 6149ce0bfa7b..299fa2febbec 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -2445,6 +2445,75 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev, } EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id); +/* + * of_genpd_attach_cpu() - Attach a CPU to its PM domain + * @cpu: The CPU to be attached. + * + * Parses the OF node of the CPU's device, to find a PM domain specifier. If + * such is found, attaches the CPU's device to the retrieved pm_domain ops and + * enables runtime PM for it. This to allow the CPU to be power managed through + * its PM domain. + * + * Returns zero when successfully attached the CPU's device to its PM domain, + * else a negative error code. + */ +int of_genpd_attach_cpu(int cpu) +{ + struct device *dev = get_cpu_device(cpu); + int ret; + + if (!dev) { + pr_warn("genpd: no dev for cpu%d\n", cpu); + return -ENODEV; + } + + ret = genpd_dev_pm_attach(dev); + if (ret != 1) { + dev_warn(dev, "genpd: attach cpu failed %d\n", ret); + return ret < 0 ? ret : -ENODEV; + } + + pm_runtime_irq_safe(dev); + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + + dev_info(dev, "genpd: attached cpu\n"); + return 0; +} +EXPORT_SYMBOL(of_genpd_attach_cpu); + +/** + * of_genpd_detach_cpu() - Detach a CPU from its PM domain + * @cpu: The CPU to be detached. + * + * Detach the CPU's device from its corresponding PM domain. If detaching is + * completed successfully, disable runtime PM and restore the runtime PM usage + * count for the CPU's device. + */ +void of_genpd_detach_cpu(int cpu) +{ + struct device *dev = get_cpu_device(cpu); + + if (!dev) { + pr_warn("genpd: no dev for cpu%d\n", cpu); + return; + } + + /* Check that the device is attached to a genpd. */ + if (!(dev->pm_domain && dev->pm_domain->detach == genpd_dev_pm_detach)) + return; + + genpd_dev_pm_detach(dev, true); + + pm_runtime_disable(dev); + pm_runtime_put_noidle(dev); + pm_runtime_reinit(dev); + + dev_info(dev, "genpd: detached cpu\n"); +} +EXPORT_SYMBOL(of_genpd_detach_cpu); + static const struct of_device_id idle_state_match[] = { { .compatible = "domain-idle-state", }, { } diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 3f67ff0c1c69..2c09cf80b285 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -243,6 +243,8 @@ unsigned int of_genpd_opp_to_performance_state(struct device *dev, int genpd_dev_pm_attach(struct device *dev); struct device *genpd_dev_pm_attach_by_id(struct device *dev, unsigned int index); +int of_genpd_attach_cpu(int cpu); +void of_genpd_detach_cpu(int cpu); #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ static inline int of_genpd_add_provider_simple(struct device_node *np, struct generic_pm_domain *genpd) @@ -294,6 +296,13 @@ static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev, return NULL; } +static inline int of_genpd_attach_cpu(int cpu) +{ + return -ENODEV; +} + +static inline void of_genpd_detach_cpu(int cpu) {} + static inline struct generic_pm_domain *of_genpd_remove_last(struct device_node *np) {
Introduce two new genpd helper functions, of_genpd_attach|detach_cpu(), which takes the CPU-number as an in-parameter. To attach a CPU to a genpd, of_genpd_attach_cpu() starts by fetching the struct device belonging to the CPU. Then it calls genpd_dev_pm_attach(), which via DT tries to hook up the CPU device to its corresponding PM domain. If it succeeds, of_genpd_attach_cpu() continues to prepare/enable runtime PM of the device. To detach a CPU from its PM domain, of_genpd_attach_cpu() reverse the operations made from of_genpd_attach_cpu(). However, first it checks that the CPU device has a valid PM domain pointer assigned, as to make sure it belongs to genpd. Cc: Lina Iyer <ilina@codeaurora.org> Co-developed-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- drivers/base/power/domain.c | 69 +++++++++++++++++++++++++++++++++++++ include/linux/pm_domain.h | 9 +++++ 2 files changed, 78 insertions(+) -- 2.17.1