diff options
| -rw-r--r-- | drivers/cpufreq/scpi-cpufreq.c | 193 |
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; } |