Register for limit change notifications if supported and use the throttled
frequency from the notification to apply HW pressure.

Signed-off-by: Sibi Sankar <redacted>
---

v3:
* Sanitize range_max received from the notifier. [Pierre]
* Update commit message.

  drivers/cpufreq/scmi-cpufreq.c | 29 ++++++++++++++++++++++++++++-
  1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 76a0ddbd9d24..78b87b72962d 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c

@@ -25,9 +25,13 @@ 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;
  };
  
+const struct scmi_handle *handle;
+static struct scmi_device *scmi_dev;
  static struct scmi_protocol_handle *ph;
  static const struct scmi_perf_proto_ops *perf_ops;
  static struct cpufreq_driver scmi_cpufreq_driver;

@@ -151,6 +155,20 @@ 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;
+
+	policy->max = clamp(limit_notify->range_max_freq/HZ_PER_KHZ, policy->cpuinfo.min_freq,
+			    policy->cpuinfo.max_freq);

+
+	cpufreq_update_pressure(policy);
+
+	return NOTIFY_OK;
+}
+
  static int scmi_cpufreq_init(struct cpufreq_policy *policy)
  {
  	int ret, nr_opp, domain;

@@ -269,6 +287,15 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
  		}
  	}
  
+	priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb;
+	ret = handle->notify_ops->devm_event_notifier_register(scmi_dev, SCMI_PROTOCOL_PERF,
+							SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED,
+							&domain,
+							&priv->limit_notify_nb);
+	if (ret)
+		dev_warn(cpu_dev,
+			 "failed to register for limits change notifier for domain %d\n", domain);
+
  	priv->policy = policy;
  
  	return 0;

@@ -342,8 +369,8 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
  {
  	int ret;
  	struct device *dev = &sdev->dev;
-	const struct scmi_handle *handle;