| Message ID | 20241030133133.2932722-2-quic_sibis@quicinc.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | firmware: arm_scmi: Register and handle limits change notification | expand |
On Wed, 30 Oct 2024 at 14:32, Sibi Sankar <quic_sibis@quicinc.com> wrote: > > Register for limit change notifications if supported and use the throttled > frequency from the notification to apply HW pressure. > > Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com> > Tested-by: Mike Tipton <quic_mdtipton@quicinc.com> > Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> > Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> > --- > > v6: > * Unregister the notifier in the exit path to make sure > the cpus work across suspend/resume cycles. > > drivers/cpufreq/scmi-cpufreq.c | 38 ++++++++++++++++++++++++++++++++++ > 1 file changed, 38 insertions(+) > > diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c > index 5892c73e129d..fb3534eae722 100644 > --- a/drivers/cpufreq/scmi-cpufreq.c > +++ b/drivers/cpufreq/scmi-cpufreq.c > @@ -16,6 +16,7 @@ > #include <linux/export.h> > #include <linux/module.h> > #include <linux/pm_opp.h> > +#include <linux/pm_qos.h> > #include <linux/slab.h> > #include <linux/scmi_protocol.h> > #include <linux/types.h> > @@ -25,7 +26,9 @@ struct scmi_data { > int domain_id; > int nr_opp; > struct device *cpu_dev; > + struct cpufreq_policy *policy; > cpumask_var_t opp_shared_cpus; > + struct notifier_block limit_notify_nb; > }; > > static struct scmi_protocol_handle *ph; > @@ -174,6 +177,25 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = { > NULL, > }; > > +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data) > +{ > + struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb); > + struct scmi_perf_limits_report *limit_notify = data; > + struct cpufreq_policy *policy = priv->policy; > + unsigned int limit_freq_khz; > + int ret; > + > + limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ; > + > + policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq); > + > + ret = freq_qos_update_request(policy->max_freq_req, policy->max); If I don't get it wrong, you are using policy->max_freq_req which is also used by the sysfs scaling_max_freq This means that your request will be overwritten by the next write into scaling_max_freq and/or you will overwrite a constraint set by userspace. You have to create your own freq_qos_request and add it to the list of cpufreq qos request > + if (ret < 0) > + pr_warn("failed to update freq constraint: %d\n", ret); > + > + return NOTIFY_OK; > +} > + > static int scmi_cpufreq_init(struct cpufreq_policy *policy) > { > int ret, nr_opp, domain; > @@ -181,6 +203,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) > struct device *cpu_dev; > struct scmi_data *priv; > struct cpufreq_frequency_table *freq_table; > + struct scmi_device *sdev = cpufreq_get_driver_data(); > > cpu_dev = get_cpu_device(policy->cpu); > if (!cpu_dev) { > @@ -294,6 +317,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) > } > } > > + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb; > + ret = sdev->handle->notify_ops->devm_event_notifier_register(sdev, SCMI_PROTOCOL_PERF, > + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, > + &domain, > + &priv->limit_notify_nb); > + if (ret) > + dev_warn(&sdev->dev, > + "failed to register for limits change notifier for domain %d\n", domain); > + > + priv->policy = policy; > + > return 0; > > out_free_opp: > @@ -310,8 +344,10 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) > > static void scmi_cpufreq_exit(struct cpufreq_policy *policy) > { > + struct scmi_device *sdev = cpufreq_get_driver_data(); > struct scmi_data *priv = policy->driver_data; > > + sdev->handle->notify_ops->devm_event_notifier_unregister(sdev, &priv->limit_notify_nb); > dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); > dev_pm_opp_remove_all_dynamic(priv->cpu_dev); > free_cpumask_var(priv->opp_shared_cpus); > @@ -370,6 +406,8 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev) > if (!handle) > return -ENODEV; > > + scmi_cpufreq_driver.driver_data = sdev; > + > perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph); > if (IS_ERR(perf_ops)) > return PTR_ERR(perf_ops); > -- > 2.34.1 >
On 10/30/24 20:17, Vincent Guittot wrote: > On Wed, 30 Oct 2024 at 14:32, Sibi Sankar <quic_sibis@quicinc.com> wrote: >> >> Register for limit change notifications if supported and use the throttled >> frequency from the notification to apply HW pressure. >> >> Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com> >> Tested-by: Mike Tipton <quic_mdtipton@quicinc.com> >> Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> >> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> >> --- >> >> v6: >> * Unregister the notifier in the exit path to make sure >> the cpus work across suspend/resume cycles. >> >> drivers/cpufreq/scmi-cpufreq.c | 38 ++++++++++++++++++++++++++++++++++ >> 1 file changed, 38 insertions(+) >> >> diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c >> index 5892c73e129d..fb3534eae722 100644 >> --- a/drivers/cpufreq/scmi-cpufreq.c >> +++ b/drivers/cpufreq/scmi-cpufreq.c >> @@ -16,6 +16,7 @@ >> #include <linux/export.h> >> #include <linux/module.h> >> #include <linux/pm_opp.h> >> +#include <linux/pm_qos.h> >> #include <linux/slab.h> >> #include <linux/scmi_protocol.h> >> #include <linux/types.h> >> @@ -25,7 +26,9 @@ struct scmi_data { >> int domain_id; >> int nr_opp; >> struct device *cpu_dev; >> + struct cpufreq_policy *policy; >> cpumask_var_t opp_shared_cpus; >> + struct notifier_block limit_notify_nb; >> }; >> >> static struct scmi_protocol_handle *ph; >> @@ -174,6 +177,25 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = { >> NULL, >> }; >> >> +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data) >> +{ >> + struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb); >> + struct scmi_perf_limits_report *limit_notify = data; >> + struct cpufreq_policy *policy = priv->policy; >> + unsigned int limit_freq_khz; >> + int ret; >> + >> + limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ; >> + >> + policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq); >> + >> + ret = freq_qos_update_request(policy->max_freq_req, policy->max); > > If I don't get it wrong, you are using policy->max_freq_req which is > also used by the sysfs scaling_max_freq > > This means that your request will be overwritten by the next write > into scaling_max_freq and/or you will overwrite a constraint set by > userspace. > > You have to create your own freq_qos_request and add it to the list of > cpufreq qos request Thanks for catching this. Will get it fixed in the next re-spin. -Sibi > > > >> + if (ret < 0) >> + pr_warn("failed to update freq constraint: %d\n", ret); >> + >> + return NOTIFY_OK; >> +} >> + >> static int scmi_cpufreq_init(struct cpufreq_policy *policy) >> { >> int ret, nr_opp, domain; >> @@ -181,6 +203,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) >> struct device *cpu_dev; >> struct scmi_data *priv; >> struct cpufreq_frequency_table *freq_table; >> + struct scmi_device *sdev = cpufreq_get_driver_data(); >> >> cpu_dev = get_cpu_device(policy->cpu); >> if (!cpu_dev) { >> @@ -294,6 +317,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) >> } >> } >> >> + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb; >> + ret = sdev->handle->notify_ops->devm_event_notifier_register(sdev, SCMI_PROTOCOL_PERF, >> + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, >> + &domain, >> + &priv->limit_notify_nb); >> + if (ret) >> + dev_warn(&sdev->dev, >> + "failed to register for limits change notifier for domain %d\n", domain); >> + >> + priv->policy = policy; >> + >> return 0; >> >> out_free_opp: >> @@ -310,8 +344,10 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) >> >> static void scmi_cpufreq_exit(struct cpufreq_policy *policy) >> { >> + struct scmi_device *sdev = cpufreq_get_driver_data(); >> struct scmi_data *priv = policy->driver_data; >> >> + sdev->handle->notify_ops->devm_event_notifier_unregister(sdev, &priv->limit_notify_nb); >> dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); >> dev_pm_opp_remove_all_dynamic(priv->cpu_dev); >> free_cpumask_var(priv->opp_shared_cpus); >> @@ -370,6 +406,8 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev) >> if (!handle) >> return -ENODEV; >> >> + scmi_cpufreq_driver.driver_data = sdev; >> + >> perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph); >> if (IS_ERR(perf_ops)) >> return PTR_ERR(perf_ops); >> -- >> 2.34.1 >>
diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 5892c73e129d..fb3534eae722 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -16,6 +16,7 @@ #include <linux/export.h> #include <linux/module.h> #include <linux/pm_opp.h> +#include <linux/pm_qos.h> #include <linux/slab.h> #include <linux/scmi_protocol.h> #include <linux/types.h> @@ -25,7 +26,9 @@ struct scmi_data { int domain_id; int nr_opp; struct device *cpu_dev; + struct cpufreq_policy *policy; cpumask_var_t opp_shared_cpus; + struct notifier_block limit_notify_nb; }; static struct scmi_protocol_handle *ph; @@ -174,6 +177,25 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = { NULL, }; +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned long event, void *data) +{ + struct scmi_data *priv = container_of(nb, struct scmi_data, limit_notify_nb); + struct scmi_perf_limits_report *limit_notify = data; + struct cpufreq_policy *policy = priv->policy; + unsigned int limit_freq_khz; + int ret; + + limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ; + + policy->max = clamp(limit_freq_khz, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq); + + ret = freq_qos_update_request(policy->max_freq_req, policy->max); + if (ret < 0) + pr_warn("failed to update freq constraint: %d\n", ret); + + return NOTIFY_OK; +} + static int scmi_cpufreq_init(struct cpufreq_policy *policy) { int ret, nr_opp, domain; @@ -181,6 +203,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) struct device *cpu_dev; struct scmi_data *priv; struct cpufreq_frequency_table *freq_table; + struct scmi_device *sdev = cpufreq_get_driver_data(); cpu_dev = get_cpu_device(policy->cpu); if (!cpu_dev) { @@ -294,6 +317,17 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) } } + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb; + ret = sdev->handle->notify_ops->devm_event_notifier_register(sdev, SCMI_PROTOCOL_PERF, + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, + &domain, + &priv->limit_notify_nb); + if (ret) + dev_warn(&sdev->dev, + "failed to register for limits change notifier for domain %d\n", domain); + + priv->policy = policy; + return 0; out_free_opp: @@ -310,8 +344,10 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) static void scmi_cpufreq_exit(struct cpufreq_policy *policy) { + struct scmi_device *sdev = cpufreq_get_driver_data(); struct scmi_data *priv = policy->driver_data; + sdev->handle->notify_ops->devm_event_notifier_unregister(sdev, &priv->limit_notify_nb); dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); dev_pm_opp_remove_all_dynamic(priv->cpu_dev); free_cpumask_var(priv->opp_shared_cpus); @@ -370,6 +406,8 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev) if (!handle) return -ENODEV; + scmi_cpufreq_driver.driver_data = sdev; + perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph); if (IS_ERR(perf_ops)) return PTR_ERR(perf_ops);