On 11/3/24 20:42, Vincent Guittot wrote:
On Thu, 31 Oct 2024 at 14:28, Sibi Sankar <quic_sibis@xxxxxxxxxxx> 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@xxxxxxxxxxx> Tested-by: Mike Tipton <quic_mdtipton@xxxxxxxxxxx> Reviewed-by: Cristian Marussi <cristian.marussi@xxxxxxx> Reviewed-by: Lukasz Luba <lukasz.luba@xxxxxxx> --- v7: * Add a new request instead of reusing the max_freq_req [Vincent] * Use the non-devm versions of register/unregister of event notifier since we have to remove them when the cpus get removed anyway. * Add new patch to fix cleanup path on boost enablement failure. drivers/cpufreq/scmi-cpufreq.c | 51 ++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 07d6f9a9b7c8..ff13f7d4b2c9 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 +26,10 @@ 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; + struct freq_qos_request limits_freq_req; }; static struct scmi_protocol_handle *ph; @@ -174,6 +178,25 @@ 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);I don't think that the above is needed or correct, the cpufreq qos notifier will take care of updating policy->max with handle_update()
Fixed this in the next re-spin. Thanks again for the review. -Sibi
+ + ret = freq_qos_update_request(&priv->limits_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 +204,7 @@ 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 +318,25 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) } } + ret = freq_qos_add_request(&policy->constraints, &priv->limits_freq_req, FREQ_QOS_MAX, + FREQ_QOS_MAX_DEFAULT_VALUE); + if (ret < 0) { + dev_err(cpu_dev, "failed to add qos limits request: %d\n", ret); + goto out_free_table; + } + + priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb; + ret = sdev->handle->notify_ops->event_notifier_register(sdev->handle, SCMI_PROTOCOL_PERF, + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, + &priv->domain_id, + &priv->limit_notify_nb); + if (ret) + dev_warn(&sdev->dev, + "failed to register for limits change notifier for domain %d\n", + priv->domain_id); + + priv->policy = policy; + return 0; out_free_table: @@ -313,7 +356,13 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) static void scmi_cpufreq_exit(struct cpufreq_policy *policy) { struct scmi_data *priv = policy->driver_data; + struct scmi_device *sdev = cpufreq_get_driver_data(); + sdev->handle->notify_ops->event_notifier_unregister(sdev->handle, SCMI_PROTOCOL_PERF, + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, + &priv->domain_id, + &priv->limit_notify_nb); + freq_qos_remove_request(&priv->limits_freq_req); 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); @@ -372,6 +421,8 @@ 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
