// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2012 Freescale Semiconductor, Inc. * * Copyright (C) 2014 Linaro. * Viresh Kumar */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include "cpufreq-dt.h" struct private_data { struct list_head node; cpumask_var_t cpus; struct device *cpu_dev; struct cpufreq_frequency_table *freq_table; bool have_static_opps; int opp_token; }; static LIST_HEAD(priv_list); static struct freq_attr *cpufreq_dt_attr[] = { &cpufreq_freq_attr_scaling_available_freqs, NULL, /* Extra space for boost-attr if required */ NULL, }; static struct private_data *cpufreq_dt_find_data(int cpu) { struct private_data *priv; list_for_each_entry(priv, &priv_list, node) { if (cpumask_test_cpu(cpu, priv->cpus)) return priv; } return NULL; } static int set_target(struct cpufreq_policy *policy, unsigned int index) { struct private_data *priv = policy->driver_data; unsigned long freq = policy->freq_table[index].frequency; return dev_pm_opp_set_rate(priv->cpu_dev, freq * 1000); } /* * An earlier version of opp-v1 bindings used to name the regulator * "cpu0-supply", we still need to handle that for backwards compatibility. */ static const char *find_supply_name(struct device *dev) { struct device_node *np __free(device_node) = of_node_get(dev->of_node); int cpu = dev->id; /* This must be valid for sure */ if (WARN_ON(!np)) return NULL; /* Try "cpu0" for older DTs */ if (!cpu && of_property_present(np, "cpu0-supply")) return "cpu0"; if (of_property_present(np, "cpu-supply")) return "cpu"; dev_dbg(dev, "no regulator for cpu%d\n", cpu); return NULL; } static int cpufreq_init(struct cpufreq_policy *policy) { struct private_data *priv; struct device *cpu_dev; struct clk *cpu_clk; unsigned int transition_latency; int ret; priv = cpufreq_dt_find_data(policy->cpu); if (!priv) { pr_err("failed to find data for cpu%d\n", policy->cpu); return -ENODEV; } cpu_dev = priv->cpu_dev; cpu_clk = clk_get(cpu_dev, NULL); if (IS_ERR(cpu_clk)) { ret = PTR_ERR(cpu_clk); dev_err(cpu_dev, "%s: failed to get clk: %d\n", __func__, ret); return ret; } transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev); if (!transition_latency) transition_latency = CPUFREQ_ETERNAL; cpumask_copy(policy->cpus, priv->cpus); policy->driver_data = priv; policy->clk = cpu_clk; policy->freq_table = priv->freq_table; policy->suspend_freq = dev_pm_opp_get_suspend_opp_freq(cpu_dev) / 1000; policy->cpuinfo.transition_latency = transition_latency; policy->dvfs_possible_from_any_cpu = true; /* Support turbo/boost mode */ if (policy_has_boost_freq(policy)) { /* This gets disabled by core on driver unregister */ ret = cpufreq_enable_boost_support(); if (ret) goto out_clk_put; cpufreq_dt_attr[1] = &cpufreq_freq_attr_scaling_boost_freqs; } return 0; out_clk_put: clk_put(cpu_clk); return ret; } static int cpufreq_online(struct cpufreq_policy *policy) { /* We did light-weight tear down earlier, nothing to do here */ return 0; } static int cpufreq_offline(struct cpufreq_policy *policy) { /* * Preserve policy->driver_data and don't free resources on light-weight * tear down. */ return 0; } static void cpufreq_exit(struct cpufreq_policy *policy) { clk_put(policy->clk); } static struct cpufreq_driver dt_cpufreq_driver = { .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK | CPUFREQ_IS_COOLING_DEV, .verify = cpufreq_generic_frequency_table_verify, .target_index = set_target, .get = cpufreq_generic_get, .init = cpufreq_init, .exit = cpufreq_exit, .online = cpufreq_online, .offline = cpufreq_offline, .register_em = cpufreq_register_em_with_opp, .name = "cpufreq-dt", .attr = cpufreq_dt_attr, .suspend = cpufreq_generic_suspend, }; static int dt_cpufreq_early_init(struct device *dev, int cpu) { struct private_data *priv; struct device *cpu_dev; bool fallback = false; const char *reg_name[] = { NULL, NULL }; int ret; /* Check if this CPU is already covered by some other policy */ if (cpufreq_dt_find_data(cpu)) return 0; cpu_dev = get_cpu_device(cpu); if (!cpu_dev) return -EPROBE_DEFER; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; if (!zalloc_cpumask_var(&priv->cpus, GFP_KERNEL)) return -ENOMEM; cpumask_set_cpu(cpu, priv->cpus); priv->cpu_dev = cpu_dev; /* * OPP layer will be taking care of regulators now, but it needs to know * the name of the regulator first. */ reg_name[0] = find_supply_name(cpu_dev); if (reg_name[0]) { priv->opp_token = dev_pm_opp_set_regulators(cpu_dev, reg_name); if (priv->opp_token < 0) { ret = dev_err_probe(cpu_dev, priv->opp_token, "failed to set regulators\n"); goto free_cpumask; } } /* Get OPP-sharing information from "operating-points-v2" bindings */ ret = dev_pm_opp_of_get_sharing_cpus(cpu_dev, priv->cpus); if (ret) { if (ret != -ENOENT) goto out; /* * operating-points-v2 not supported, fallback to all CPUs share * OPP for backward compatibility if the platform hasn't set * sharing CPUs. */ if (dev_pm_opp_get_sharing_cpus(cpu_dev, priv->cpus)) fallback = true; } /* * Initialize OPP tables for all priv->cpus. They will be shared by * all CPUs which have marked their CPUs shared with OPP bindings. * * For platforms not using operating-points-v2 bindings, we do this * before updating priv->cpus. Otherwise, we will end up creating * duplicate OPPs for the CPUs. * * OPPs might be populated at runtime, don't fail for error here unless * it is -EPROBE_DEFER. */ ret = dev_pm_opp_of_cpumask_add_table(priv->cpus); if (!ret) { priv->have_static_opps = true; } else if (ret == -EPROBE_DEFER) { goto out; } /* * The OPP table must be initialized, statically or dynamically, by this * point. */ ret = dev_pm_opp_get_opp_count(cpu_dev); if (ret <= 0) { dev_err(cpu_dev, "OPP table can't be empty\n"); ret = -ENODEV; goto out; } if (fallback) { cpumask_setall(priv->cpus); ret = dev_pm_opp_set_sharing_cpus(cpu_dev, priv->cpus); if (ret) dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n", __func__, ret); } ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &priv->freq_table); if (ret) { dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret); goto out; } list_add(&priv->node, &priv_list); return 0; out: if (priv->have_static_opps) dev_pm_opp_of_cpumask_remove_table(priv->cpus); dev_pm_opp_put_regulators(priv->opp_token); free_cpumask: free_cpumask_var(priv->cpus); return ret; } static void dt_cpufreq_release(void) { struct private_data *priv, *tmp; list_for_each_entry_safe(priv, tmp, &priv_list, node) { dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &priv->freq_table); if (priv->have_static_opps) dev_pm_opp_of_cpumask_remove_table(priv->cpus); dev_pm_opp_put_regulators(priv->opp_token); free_cpumask_var(priv->cpus); list_del(&priv->node); } } static int dt_cpufreq_probe(struct platform_device *pdev) { struct cpufreq_dt_platform_data *data = dev_get_platdata(&pdev->dev); int ret, cpu; /* Request resources early so we can return in case of -EPROBE_DEFER */ for_each_possible_cpu(cpu) { ret = dt_cpufreq_early_init(&pdev->dev, cpu); if (ret) goto err; } if (data) { if (data->have_governor_per_policy) dt_cpufreq_driver.flags |= CPUFREQ_HAVE_GOVERNOR_PER_POLICY; dt_cpufreq_driver.resume = data->resume; if (data->suspend) dt_cpufreq_driver.suspend = data->suspend; if (data->get_intermediate) { dt_cpufreq_driver.target_intermediate = data->target_intermediate; dt_cpufreq_driver.get_intermediate = data->get_intermediate; } } ret = cpufreq_register_driver(&dt_cpufreq_driver); if (ret) { dev_err(&pdev->dev, "failed register driver: %d\n", ret); goto err; } return 0; err: dt_cpufreq_release(); return ret; } static void dt_cpufreq_remove(struct platform_device *pdev) { cpufreq_unregister_driver(&dt_cpufreq_driver); dt_cpufreq_release(); } static struct platform_driver dt_cpufreq_platdrv = { .driver = { .name = "cpufreq-dt", }, .probe = dt_cpufreq_probe, .remove = dt_cpufreq_remove, }; module_platform_driver(dt_cpufreq_platdrv); MODULE_ALIAS("platform:cpufreq-dt"); MODULE_AUTHOR("Viresh Kumar "); MODULE_AUTHOR("Shawn Guo "); MODULE_DESCRIPTION("Generic cpufreq driver"); MODULE_LICENSE("GPL");