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path: root/drivers/cpufreq/scpi-cpufreq.c
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Diffstat (limited to 'drivers/cpufreq/scpi-cpufreq.c')
-rw-r--r--drivers/cpufreq/scpi-cpufreq.c193
1 files changed, 178 insertions, 15 deletions
diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c
index 05d299052c5c..247fcbfa4cb5 100644
--- a/drivers/cpufreq/scpi-cpufreq.c
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -18,27 +18,89 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/clk.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
+#include <linux/cpu_cooling.h>
+#include <linux/export.h>
#include <linux/module.h>
-#include <linux/platform_device.h>
+#include <linux/of_platform.h>
#include <linux/pm_opp.h>
#include <linux/scpi_protocol.h>
+#include <linux/slab.h>
#include <linux/types.h>
-#include "arm_big_little.h"
+struct scpi_data {
+ struct clk *clk;
+ struct device *cpu_dev;
+ struct thermal_cooling_device *cdev;
+};
static struct scpi_ops *scpi_ops;
-static int scpi_get_transition_latency(struct device *cpu_dev)
+static unsigned int scpi_cpufreq_get_rate(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
+ struct scpi_data *priv = policy->driver_data;
+ unsigned long rate = clk_get_rate(priv->clk);
+
+ return rate / 1000;
+}
+
+static int
+scpi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index)
+{
+ struct scpi_data *priv = policy->driver_data;
+ u64 rate = policy->freq_table[index].frequency * 1000;
+ int ret;
+
+ ret = clk_set_rate(priv->clk, rate);
+ if (!ret && (clk_get_rate(priv->clk) != rate))
+ ret = -EIO;
+
+ return ret;
+}
+
+static int
+scpi_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
{
- return scpi_ops->get_transition_latency(cpu_dev);
+ int cpu, domain, tdomain;
+ struct device *tcpu_dev;
+
+ domain = scpi_ops->device_domain_id(cpu_dev);
+ if (domain < 0)
+ return domain;
+
+ for_each_possible_cpu(cpu) {
+ if (cpu == cpu_dev->id)
+ continue;
+
+ tcpu_dev = get_cpu_device(cpu);
+ if (!tcpu_dev)
+ continue;
+
+ tdomain = scpi_ops->device_domain_id(tcpu_dev);
+ if (tdomain == domain)
+ cpumask_set_cpu(cpu, cpumask);
+ }
+
+ return 0;
}
-static int scpi_init_opp_table(const struct cpumask *cpumask)
+static int scpi_cpufreq_init(struct cpufreq_policy *policy)
{
int ret;
- struct device *cpu_dev = get_cpu_device(cpumask_first(cpumask));
+ unsigned int latency;
+ struct device *cpu_dev;
+ struct scpi_data *priv;
+ struct cpufreq_frequency_table *freq_table;
+
+ cpu_dev = get_cpu_device(policy->cpu);
+ if (!cpu_dev) {
+ pr_err("failed to get cpu%d device\n", policy->cpu);
+ return -ENODEV;
+ }
ret = scpi_ops->add_opps_to_device(cpu_dev);
if (ret) {
@@ -46,32 +108,133 @@ static int scpi_init_opp_table(const struct cpumask *cpumask)
return ret;
}
- ret = dev_pm_opp_set_sharing_cpus(cpu_dev, cpumask);
- if (ret)
+ ret = scpi_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;
+ }
+
+ ret = dev_pm_opp_get_opp_count(cpu_dev);
+ if (ret <= 0) {
+ dev_dbg(cpu_dev, "OPP table is not ready, deferring probe\n");
+ ret = -EPROBE_DEFER;
+ goto out_free_opp;
+ }
+
+ 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;
+ }
+
+ priv->cpu_dev = cpu_dev;
+ priv->clk = clk_get(cpu_dev, NULL);
+ if (IS_ERR(priv->clk)) {
+ dev_err(cpu_dev, "%s: Failed to get clk for cpu: %d\n",
+ __func__, cpu_dev->id);
+ goto out_free_cpufreq_table;
+ }
+
+ policy->driver_data = priv;
+
+ ret = cpufreq_table_validate_and_show(policy, freq_table);
+ if (ret) {
+ dev_err(cpu_dev, "%s: invalid frequency table: %d\n", __func__,
+ ret);
+ goto out_put_clk;
+ }
+
+ /* scpi allows DVFS request for any domain from any CPU */
+ policy->dvfs_possible_from_any_cpu = true;
+
+ latency = scpi_ops->get_transition_latency(cpu_dev);
+ if (!latency)
+ latency = CPUFREQ_ETERNAL;
+
+ policy->cpuinfo.transition_latency = latency;
+
+ policy->fast_switch_possible = false;
+ return 0;
+
+out_put_clk:
+ clk_put(priv->clk);
+out_free_cpufreq_table:
+ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+out_free_priv:
+ kfree(priv);
+out_free_opp:
+ dev_pm_opp_cpumask_remove_table(policy->cpus);
+
return ret;
}
-static const struct cpufreq_arm_bL_ops scpi_cpufreq_ops = {
- .name = "scpi",
- .get_transition_latency = scpi_get_transition_latency,
- .init_opp_table = scpi_init_opp_table,
- .free_opp_table = dev_pm_opp_cpumask_remove_table,
+static int scpi_cpufreq_exit(struct cpufreq_policy *policy)
+{
+ struct scpi_data *priv = policy->driver_data;
+
+ cpufreq_cooling_unregister(priv->cdev);
+ clk_put(priv->clk);
+ dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
+ kfree(priv);
+ dev_pm_opp_cpumask_remove_table(policy->related_cpus);
+
+ return 0;
+}
+
+static void scpi_cpufreq_ready(struct cpufreq_policy *policy)
+{
+ struct scpi_data *priv = policy->driver_data;
+ struct thermal_cooling_device *cdev;
+
+ cdev = of_cpufreq_cooling_register(policy);
+ if (!IS_ERR(cdev))
+ priv->cdev = cdev;
+}
+
+static struct cpufreq_driver scpi_cpufreq_driver = {
+ .name = "scpi-cpufreq",
+ .flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
+ CPUFREQ_NEED_INITIAL_FREQ_CHECK,
+ .verify = cpufreq_generic_frequency_table_verify,
+ .attr = cpufreq_generic_attr,
+ .get = scpi_cpufreq_get_rate,
+ .init = scpi_cpufreq_init,
+ .exit = scpi_cpufreq_exit,
+ .ready = scpi_cpufreq_ready,
+ .target_index = scpi_cpufreq_set_target,
};
static int scpi_cpufreq_probe(struct platform_device *pdev)
{
+ int ret;
+
scpi_ops = get_scpi_ops();
if (!scpi_ops)
return -EIO;
- return bL_cpufreq_register(&scpi_cpufreq_ops);
+ ret = cpufreq_register_driver(&scpi_cpufreq_driver);
+ if (ret)
+ dev_err(&pdev->dev, "%s: registering cpufreq failed, err: %d\n",
+ __func__, ret);
+ return ret;
}
static int scpi_cpufreq_remove(struct platform_device *pdev)
{
- bL_cpufreq_unregister(&scpi_cpufreq_ops);
+ cpufreq_unregister_driver(&scpi_cpufreq_driver);
scpi_ops = NULL;
return 0;
}