[PATCH v6 2/4] scmi-cpufreq: Move CPU initialisation to probe
Nicola Mazzucato
nicola.mazzucato at arm.com
Mon Jan 11 10:45:22 EST 2021
Some of the cpu related initialisation can be done at probe stage.
This patch moves those initialisations from the ->init callback to the
probe stage.
This is done in preparation for adding support to retrieve additional
information from DT (CPUs sharing v/f lines).
Signed-off-by: Nicola Mazzucato <nicola.mazzucato at arm.com>
---
drivers/cpufreq/scmi-cpufreq.c | 180 ++++++++++++++++++++++++---------
1 file changed, 135 insertions(+), 45 deletions(-)
diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 15b213ed78fa..4aa97cdc5997 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -25,6 +25,14 @@ struct scmi_data {
struct device *cpu_dev;
};
+/* Per-CPU storage for runtime management */
+struct scmi_cpudata {
+ cpumask_var_t scmi_shared_cpus;
+ struct cpufreq_frequency_table *freq_table;
+};
+
+static struct scmi_cpudata *cpudata_table;
+
static const struct scmi_handle *handle;
static unsigned int scmi_cpufreq_get_rate(unsigned int cpu)
@@ -120,13 +128,10 @@ scmi_get_cpu_power(unsigned long *power, unsigned long *KHz,
static int scmi_cpufreq_init(struct cpufreq_policy *policy)
{
- int ret, nr_opp;
+ int ret;
unsigned int latency;
struct device *cpu_dev;
struct scmi_data *priv;
- struct cpufreq_frequency_table *freq_table;
- struct em_data_callback em_cb = EM_DATA_CB(scmi_get_cpu_power);
- bool power_scale_mw;
cpu_dev = get_cpu_device(policy->cpu);
if (!cpu_dev) {
@@ -134,42 +139,19 @@ 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;
- }
-
- ret = scmi_get_sharing_cpus(cpu_dev, policy->cpus);
- if (ret) {
- dev_warn(cpu_dev, "failed to get sharing cpumask\n");
- return ret;
- }
-
- 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;
- }
-
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv) {
ret = -ENOMEM;
goto out_free_opp;
}
- ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
- if (ret) {
- dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
- goto out_free_priv;
- }
+ cpumask_copy(policy->cpus, cpudata_table[policy->cpu].scmi_shared_cpus);
priv->cpu_dev = cpu_dev;
priv->domain_id = handle->perf_ops->device_domain_id(cpu_dev);
policy->driver_data = priv;
- policy->freq_table = freq_table;
+ policy->freq_table = cpudata_table[policy->cpu].freq_table;
/* SCMI allows DVFS request for any domain from any CPU */
policy->dvfs_possible_from_any_cpu = true;
@@ -183,23 +165,8 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
policy->fast_switch_possible =
handle->perf_ops->fast_switch_possible(handle, cpu_dev);
- 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_priv;
- }
-
- 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);
-
return 0;
-out_free_priv:
- kfree(priv);
out_free_opp:
dev_pm_opp_remove_all_dynamic(cpu_dev);
@@ -210,7 +177,6 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy)
{
struct scmi_data *priv = policy->driver_data;
- dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
kfree(priv);
@@ -231,10 +197,102 @@ static struct cpufreq_driver scmi_cpufreq_driver = {
.exit = scmi_cpufreq_exit,
};
+static int scmi_init_cpudata(void)
+{
+ int cpu;
+ unsigned int ncpus = num_possible_cpus();
+
+ cpudata_table = kzalloc(sizeof(*cpudata_table) * ncpus, GFP_KERNEL);
+ if (!cpudata_table)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ if (!zalloc_cpumask_var(&cpudata_table[cpu].scmi_shared_cpus,
+ GFP_KERNEL))
+ goto out;
+ }
+
+ return 0;
+
+out:
+ kfree(cpudata_table);
+ return -ENOMEM;
+}
+
+static int scmi_init_device(const struct scmi_handle *handle, int cpu)
+{
+ struct device *cpu_dev;
+ int ret, nr_opp;
+ struct em_data_callback em_cb = EM_DATA_CB(scmi_get_cpu_power);
+ bool power_scale_mw;
+ cpumask_var_t scmi_cpus;
+
+ if (!zalloc_cpumask_var(&scmi_cpus, GFP_KERNEL))
+ return -ENOMEM;
+
+ cpumask_set_cpu(cpu, scmi_cpus);
+
+ cpu_dev = get_cpu_device(cpu);
+
+ ret = scmi_get_sharing_cpus(cpu_dev, scmi_cpus);
+ if (ret) {
+ dev_warn(cpu_dev, "failed to get sharing cpumask\n");
+ goto free_cpumask;
+ }
+
+ /*
+ * We get here for each CPU. Add OPPs only on those CPUs for which we
+ * haven't already done so, or set their OPPs as shared.
+ */
+ nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
+ if (nr_opp <= 0) {
+ ret = handle->perf_ops->device_opps_add(handle, cpu_dev);
+ if (ret) {
+ dev_warn(cpu_dev, "failed to add opps to the device\n");
+ goto free_cpumask;
+ }
+
+ ret = dev_pm_opp_set_sharing_cpus(cpu_dev, scmi_cpus);
+ if (ret) {
+ dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
+ __func__, ret);
+ goto 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 free_cpumask;
+ }
+
+ power_scale_mw = handle->perf_ops->power_scale_mw_get(handle);
+ em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb, scmi_cpus,
+ power_scale_mw);
+ }
+
+ ret = dev_pm_opp_init_cpufreq_table(cpu_dev,
+ &cpudata_table[cpu].freq_table);
+ if (ret) {
+ dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
+ goto free_cpumask;
+ }
+
+ cpumask_copy(cpudata_table[cpu].scmi_shared_cpus, scmi_cpus);
+
+free_cpumask:
+ free_cpumask_var(scmi_cpus);
+ return ret;
+}
+
static int scmi_cpufreq_probe(struct scmi_device *sdev)
{
int ret;
struct device *dev = &sdev->dev;
+ int cpu;
+ struct device *cpu_dev;
handle = sdev->handle;
@@ -247,6 +305,24 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, NULL);
#endif
+ ret = scmi_init_cpudata();
+ if (ret) {
+ pr_err("%s: init cpu data failed\n", __func__);
+ return ret;
+ }
+
+ for_each_possible_cpu(cpu) {
+ cpu_dev = get_cpu_device(cpu);
+
+ ret = scmi_init_device(handle, cpu);
+ if (ret) {
+ dev_err(cpu_dev, "%s: init device failed\n",
+ __func__);
+
+ return ret;
+ }
+ }
+
ret = cpufreq_register_driver(&scmi_cpufreq_driver);
if (ret) {
dev_err(dev, "%s: registering cpufreq failed, err: %d\n",
@@ -258,6 +334,20 @@ static int scmi_cpufreq_probe(struct scmi_device *sdev)
static void scmi_cpufreq_remove(struct scmi_device *sdev)
{
+ int cpu;
+ struct device *cpu_dev;
+
+ for_each_possible_cpu(cpu) {
+ cpu_dev = get_cpu_device(cpu);
+
+ dev_pm_opp_free_cpufreq_table(cpu_dev,
+ &cpudata_table[cpu].freq_table);
+
+ free_cpumask_var(cpudata_table[cpu].scmi_shared_cpus);
+ }
+
+ kfree(cpudata_table);
+
cpufreq_unregister_driver(&scmi_cpufreq_driver);
}
--
2.27.0
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