1 files changed, 73 insertions, 34 deletions

diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 5bd03b59887f..c8a4364ad3c2 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -2,7 +2,7 @@
 /*
  * System Control and Power Interface (SCMI) based CPUFreq Interface driver
  *
- * Copyright (C) 2018 ARM Ltd.
+ * Copyright (C) 2018-2021 ARM Ltd.
  * Sudeep Holla <sudeep.holla@arm.com>
  */
 
@@ -25,17 +25,17 @@ struct scmi_data {
 	struct device *cpu_dev;
 };
 
-static const struct scmi_handle *handle;
+static struct scmi_protocol_handle *ph;
+static const struct scmi_perf_proto_ops *perf_ops;
 
 static unsigned int scmi_cpufreq_get_rate(unsigned int cpu)
 {
 	struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
-	const struct scmi_perf_ops *perf_ops = handle->perf_ops;
 	struct scmi_data *priv = policy->driver_data;
 	unsigned long rate;
 	int ret;
 
-	ret = perf_ops->freq_get(handle, priv->domain_id, &rate, false);
+	ret = perf_ops->freq_get(ph, priv->domain_id, &rate, false);
 	if (ret)
 		return 0;
 	return rate / 1000;
@@ -50,19 +50,17 @@ static int
 scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index)
 {
 	struct scmi_data *priv = policy->driver_data;
-	const struct scmi_perf_ops *perf_ops = handle->perf_ops;
 	u64 freq = policy->freq_table[index].frequency;
 
-	return perf_ops->freq_set(handle, priv->domain_id, freq * 1000, false);
+	return perf_ops->freq_set(ph, priv->domain_id, freq * 1000, false);
 }
 
 static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 					     unsigned int target_freq)
 {
 	struct scmi_data *priv = policy->driver_data;
-	const struct scmi_perf_ops *perf_ops = handle->perf_ops;
 
-	if (!perf_ops->freq_set(handle, priv->domain_id,
+	if (!perf_ops->freq_set(ph, priv->domain_id,
 				target_freq * 1000, true))
 		return target_freq;
 
@@ -75,7 +73,7 @@ scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
 	int cpu, domain, tdomain;
 	struct device *tcpu_dev;
 
-	domain = handle->perf_ops->device_domain_id(cpu_dev);
+	domain = perf_ops->device_domain_id(cpu_dev);
 	if (domain < 0)
 		return domain;
 
@@ -87,7 +85,7 @@ scmi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
 		if (!tcpu_dev)
 			continue;
 
-		tdomain = handle->perf_ops->device_domain_id(tcpu_dev);
+		tdomain = perf_ops->device_domain_id(tcpu_dev);
 		if (tdomain == domain)
 			cpumask_set_cpu(cpu, cpumask);
 	}
@@ -102,13 +100,13 @@ scmi_get_cpu_power(unsigned long *power, unsigned long *KHz,
 	unsigned long Hz;
 	int ret, domain;
 
-	domain = handle->perf_ops->device_domain_id(cpu_dev);
+	domain = perf_ops->device_domain_id(cpu_dev);
 	if (domain < 0)
 		return domain;
 
 	/* Get the power cost of the performance domain. */
 	Hz = *KHz * 1000;
-	ret = handle->perf_ops->est_power_get(handle, domain, &Hz, power);
+	ret = perf_ops->est_power_get(ph, domain, &Hz, power);
 	if (ret)
 		return ret;
 
@@ -126,6 +124,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
 	struct scmi_data *priv;
 	struct cpufreq_frequency_table *freq_table;
 	struct em_data_callback em_cb = EM_DATA_CB(scmi_get_cpu_power);
+	cpumask_var_t opp_shared_cpus;
 	bool power_scale_mw;
 
 	cpu_dev = get_cpu_device(policy->cpu);
@@ -134,30 +133,64 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
 		return -ENODEV;
 	}
 
-	ret = handle->perf_ops->device_opps_add(handle, cpu_dev);
-	if (ret) {
-		dev_warn(cpu_dev, "failed to add opps to the device\n");
-		return ret;
-	}
+	if (!zalloc_cpumask_var(&opp_shared_cpus, GFP_KERNEL))
+		ret = -ENOMEM;
 
+	/* Obtain CPUs that share SCMI performance controls */
 	ret = scmi_get_sharing_cpus(cpu_dev, policy->cpus);
 	if (ret) {
 		dev_warn(cpu_dev, "failed to get sharing cpumask\n");
-		return ret;
+		goto out_free_cpumask;
 	}
 
-	ret = dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus);
-	if (ret) {
-		dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
-			__func__, ret);
-		return ret;
+	/*
+	 * Obtain CPUs that share performance levels.
+	 * The OPP 'sharing cpus' info may come from DT through an empty opp
+	 * table and opp-shared.
+	 */
+	ret = dev_pm_opp_of_get_sharing_cpus(cpu_dev, opp_shared_cpus);
+	if (ret || !cpumask_weight(opp_shared_cpus)) {
+		/*
+		 * Either opp-table is not set or no opp-shared was found.
+		 * Use the CPU mask from SCMI to designate CPUs sharing an OPP
+		 * table.
+		 */
+		cpumask_copy(opp_shared_cpus, policy->cpus);
 	}
 
+	 /*
+	  * A previous CPU may have marked OPPs as shared for a few CPUs, based on
+	  * what OPP core provided. If the current CPU is part of those few, then
+	  * there is no need to add OPPs again.
+	  */
 	nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
 	if (nr_opp <= 0) {
-		dev_dbg(cpu_dev, "OPP table is not ready, deferring probe\n");
-		ret = -EPROBE_DEFER;
-		goto out_free_opp;
+		ret = perf_ops->device_opps_add(ph, cpu_dev);
+		if (ret) {
+			dev_warn(cpu_dev, "failed to add opps to the device\n");
+			goto out_free_cpumask;
+		}
+
+		nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
+		if (nr_opp <= 0) {
+			dev_err(cpu_dev, "%s: No OPPs for this device: %d\n",
+				__func__, ret);
+
+			ret = -ENODEV;
+			goto out_free_opp;
+		}
+
+		ret = dev_pm_opp_set_sharing_cpus(cpu_dev, opp_shared_cpus);
+		if (ret) {
+			dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
+				__func__, ret);
+
+			goto out_free_opp;
+		}
+
+		power_scale_mw = perf_ops->power_scale_mw_get(ph);
+		em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb,
+					    opp_shared_cpus, power_scale_mw);
 	}
 
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
@@ -173,7 +206,7 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
 	}
 
 	priv->cpu_dev = cpu_dev;
-	priv->domain_id = handle->perf_ops->device_domain_id(cpu_dev);
+	priv->domain_id = perf_ops->device_domain_id(cpu_dev);
 
 	policy->driver_data = priv;
 	policy->freq_table = freq_table;
@@ -181,26 +214,27 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
 	/* SCMI allows DVFS request for any domain from any CPU */
 	policy->dvfs_possible_from_any_cpu = true;
 
-	latency = handle->perf_ops->transition_latency_get(handle, cpu_dev);
+	latency = perf_ops->transition_latency_get(ph, cpu_dev);
 	if (!latency)
 		latency = CPUFREQ_ETERNAL;
 
 	policy->cpuinfo.transition_latency = latency;
 
 	policy->fast_switch_possible =
-		handle->perf_ops->fast_switch_possible(handle, cpu_dev);
-
-	power_scale_mw = handle->perf_ops->power_scale_mw_get(handle);
-	em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb, policy->cpus,
-				    power_scale_mw);
+		perf_ops->fast_switch_possible(ph, cpu_dev);
 
+	free_cpumask_var(opp_shared_cpus);
 	return 0;
 
 out_free_priv:
 	kfree(priv);
+
 out_free_opp:
 	dev_pm_opp_remove_all_dynamic(cpu_dev);
 
+out_free_cpumask:
+	free_cpumask_var(opp_shared_cpus);
+
 	return ret;
 }
 
@@ -233,12 +267,17 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
 {
 	int ret;
 	struct device *dev = &sdev->dev;
+	const struct scmi_handle *handle;
 
 	handle = sdev->handle;
 
-	if (!handle || !handle->perf_ops)
+	if (!handle)
 		return -ENODEV;
 
+	perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph);
+	if (IS_ERR(perf_ops))
+		return PTR_ERR(perf_ops);
+
 #ifdef CONFIG_COMMON_CLK
 	/* dummy clock provider as needed by OPP if clocks property is used */
 	if (of_find_property(dev->of_node, "#clock-cells", NULL))