diff options
Diffstat (limited to 'drivers/cpufreq/airoha-cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/airoha-cpufreq.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/cpufreq/airoha-cpufreq.c b/drivers/cpufreq/airoha-cpufreq.c new file mode 100644 index 000000000000..4fe39eadd163 --- /dev/null +++ b/drivers/cpufreq/airoha-cpufreq.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bitfield.h> +#include <linux/cpufreq.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_domain.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> + +#include "cpufreq-dt.h" + +struct airoha_cpufreq_priv { + int opp_token; + struct dev_pm_domain_list *pd_list; + struct platform_device *cpufreq_dt; +}; + +static struct platform_device *cpufreq_pdev; + +/* NOP function to disable OPP from setting clock */ +static int airoha_cpufreq_config_clks_nop(struct device *dev, + struct opp_table *opp_table, + struct dev_pm_opp *opp, + void *data, bool scaling_down) +{ + return 0; +} + +static const char * const airoha_cpufreq_clk_names[] = { "cpu", NULL }; +static const char * const airoha_cpufreq_pd_names[] = { "perf" }; + +static int airoha_cpufreq_probe(struct platform_device *pdev) +{ + const struct dev_pm_domain_attach_data attach_data = { + .pd_names = airoha_cpufreq_pd_names, + .num_pd_names = ARRAY_SIZE(airoha_cpufreq_pd_names), + .pd_flags = PD_FLAG_DEV_LINK_ON | PD_FLAG_REQUIRED_OPP, + }; + struct dev_pm_opp_config config = { + .clk_names = airoha_cpufreq_clk_names, + .config_clks = airoha_cpufreq_config_clks_nop, + }; + struct platform_device *cpufreq_dt; + struct airoha_cpufreq_priv *priv; + struct device *dev = &pdev->dev; + struct device *cpu_dev; + int ret; + + /* CPUs refer to the same OPP table */ + cpu_dev = get_cpu_device(0); + if (!cpu_dev) + return -ENODEV; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + /* Set OPP table conf with NOP config_clks */ + priv->opp_token = dev_pm_opp_set_config(cpu_dev, &config); + if (priv->opp_token < 0) + return dev_err_probe(dev, priv->opp_token, "Failed to set OPP config\n"); + + /* Attach PM for OPP */ + ret = dev_pm_domain_attach_list(cpu_dev, &attach_data, + &priv->pd_list); + if (ret) + goto clear_opp_config; + + cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0); + ret = PTR_ERR_OR_ZERO(cpufreq_dt); + if (ret) { + dev_err(dev, "failed to create cpufreq-dt device: %d\n", ret); + goto detach_pm; + } + + priv->cpufreq_dt = cpufreq_dt; + platform_set_drvdata(pdev, priv); + + return 0; + +detach_pm: + dev_pm_domain_detach_list(priv->pd_list); +clear_opp_config: + dev_pm_opp_clear_config(priv->opp_token); + + return ret; +} + +static void airoha_cpufreq_remove(struct platform_device *pdev) +{ + struct airoha_cpufreq_priv *priv = platform_get_drvdata(pdev); + + platform_device_unregister(priv->cpufreq_dt); + + dev_pm_domain_detach_list(priv->pd_list); + + dev_pm_opp_clear_config(priv->opp_token); +} + +static struct platform_driver airoha_cpufreq_driver = { + .probe = airoha_cpufreq_probe, + .remove = airoha_cpufreq_remove, + .driver = { + .name = "airoha-cpufreq", + }, +}; + +static const struct of_device_id airoha_cpufreq_match_list[] __initconst = { + { .compatible = "airoha,en7581" }, + {}, +}; +MODULE_DEVICE_TABLE(of, airoha_cpufreq_match_list); + +static int __init airoha_cpufreq_init(void) +{ + struct device_node *np = of_find_node_by_path("/"); + const struct of_device_id *match; + int ret; + + if (!np) + return -ENODEV; + + match = of_match_node(airoha_cpufreq_match_list, np); + of_node_put(np); + if (!match) + return -ENODEV; + + ret = platform_driver_register(&airoha_cpufreq_driver); + if (unlikely(ret < 0)) + return ret; + + cpufreq_pdev = platform_device_register_data(NULL, "airoha-cpufreq", + -1, match, sizeof(*match)); + ret = PTR_ERR_OR_ZERO(cpufreq_pdev); + if (ret) + platform_driver_unregister(&airoha_cpufreq_driver); + + return ret; +} +module_init(airoha_cpufreq_init); + +static void __exit airoha_cpufreq_exit(void) +{ + platform_device_unregister(cpufreq_pdev); + platform_driver_unregister(&airoha_cpufreq_driver); +} +module_exit(airoha_cpufreq_exit); + +MODULE_AUTHOR("Christian Marangi <ansuelsmth@gmail.com>"); +MODULE_DESCRIPTION("CPUfreq driver for Airoha SoCs"); +MODULE_LICENSE("GPL"); |