diff options
Diffstat (limited to 'drivers/pmdomain/arm/scmi_perf_domain.c')
| -rw-r--r-- | drivers/pmdomain/arm/scmi_perf_domain.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/drivers/pmdomain/arm/scmi_perf_domain.c b/drivers/pmdomain/arm/scmi_perf_domain.c new file mode 100644 index 000000000000..bc3f78abb6da --- /dev/null +++ b/drivers/pmdomain/arm/scmi_perf_domain.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SCMI performance domain support. + * + * Copyright (C) 2023 Linaro Ltd. + */ + +#include <linux/err.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/pm_domain.h> +#include <linux/pm_opp.h> +#include <linux/scmi_protocol.h> +#include <linux/slab.h> + +struct scmi_perf_domain { + struct generic_pm_domain genpd; + const struct scmi_perf_proto_ops *perf_ops; + const struct scmi_protocol_handle *ph; + const struct scmi_perf_domain_info *info; + u32 domain_id; +}; + +#define to_scmi_pd(pd) container_of(pd, struct scmi_perf_domain, genpd) + +static int +scmi_pd_set_perf_state(struct generic_pm_domain *genpd, unsigned int state) +{ + struct scmi_perf_domain *pd = to_scmi_pd(genpd); + int ret; + + if (!pd->info->set_perf) + return 0; + + if (!state) + return -EINVAL; + + ret = pd->perf_ops->level_set(pd->ph, pd->domain_id, state, true); + if (ret) + dev_warn(&genpd->dev, "Failed with %d when trying to set %d perf level", + ret, state); + + return ret; +} + +static int +scmi_pd_attach_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + struct scmi_perf_domain *pd = to_scmi_pd(genpd); + int ret; + + /* + * Allow the device to be attached, but don't add the OPP table unless + * the performance level can be changed. + */ + if (!pd->info->set_perf) + return 0; + + ret = pd->perf_ops->device_opps_add(pd->ph, dev, pd->domain_id); + if (ret) + dev_warn(dev, "failed to add OPPs for the device\n"); + + return ret; +} + +static void +scmi_pd_detach_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + struct scmi_perf_domain *pd = to_scmi_pd(genpd); + + if (!pd->info->set_perf) + return; + + dev_pm_opp_remove_all_dynamic(dev); +} + +static int scmi_perf_domain_probe(struct scmi_device *sdev) +{ + struct device *dev = &sdev->dev; + const struct scmi_handle *handle = sdev->handle; + const struct scmi_perf_proto_ops *perf_ops; + struct scmi_protocol_handle *ph; + struct scmi_perf_domain *scmi_pd; + struct genpd_onecell_data *scmi_pd_data; + struct generic_pm_domain **domains; + int num_domains, i, ret = 0; + + if (!handle) + return -ENODEV; + + /* The OF node must specify us as a power-domain provider. */ + if (!of_find_property(dev->of_node, "#power-domain-cells", NULL)) + return 0; + + perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph); + if (IS_ERR(perf_ops)) + return PTR_ERR(perf_ops); + + num_domains = perf_ops->num_domains_get(ph); + if (num_domains < 0) { + dev_warn(dev, "Failed with %d when getting num perf domains\n", + num_domains); + return num_domains; + } else if (!num_domains) { + return 0; + } + + scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL); + if (!scmi_pd) + return -ENOMEM; + + scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL); + if (!scmi_pd_data) + return -ENOMEM; + + domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL); + if (!domains) + return -ENOMEM; + + for (i = 0; i < num_domains; i++, scmi_pd++) { + scmi_pd->info = perf_ops->info_get(ph, i); + + scmi_pd->domain_id = i; + scmi_pd->perf_ops = perf_ops; + scmi_pd->ph = ph; + scmi_pd->genpd.name = scmi_pd->info->name; + scmi_pd->genpd.flags = GENPD_FLAG_ALWAYS_ON | + GENPD_FLAG_OPP_TABLE_FW; + scmi_pd->genpd.set_performance_state = scmi_pd_set_perf_state; + scmi_pd->genpd.attach_dev = scmi_pd_attach_dev; + scmi_pd->genpd.detach_dev = scmi_pd_detach_dev; + + ret = pm_genpd_init(&scmi_pd->genpd, NULL, false); + if (ret) + goto err; + + domains[i] = &scmi_pd->genpd; + } + + scmi_pd_data->domains = domains; + scmi_pd_data->num_domains = num_domains; + + ret = of_genpd_add_provider_onecell(dev->of_node, scmi_pd_data); + if (ret) + goto err; + + dev_set_drvdata(dev, scmi_pd_data); + dev_info(dev, "Initialized %d performance domains", num_domains); + return 0; +err: + for (i--; i >= 0; i--) + pm_genpd_remove(domains[i]); + return ret; +} + +static void scmi_perf_domain_remove(struct scmi_device *sdev) +{ + struct device *dev = &sdev->dev; + struct genpd_onecell_data *scmi_pd_data = dev_get_drvdata(dev); + int i; + + of_genpd_del_provider(dev->of_node); + + for (i = 0; i < scmi_pd_data->num_domains; i++) + pm_genpd_remove(scmi_pd_data->domains[i]); +} + +static const struct scmi_device_id scmi_id_table[] = { + { SCMI_PROTOCOL_PERF, "perf" }, + { }, +}; +MODULE_DEVICE_TABLE(scmi, scmi_id_table); + +static struct scmi_driver scmi_perf_domain_driver = { + .name = "scmi-perf-domain", + .probe = scmi_perf_domain_probe, + .remove = scmi_perf_domain_remove, + .id_table = scmi_id_table, +}; +module_scmi_driver(scmi_perf_domain_driver); + +MODULE_AUTHOR("Ulf Hansson <ulf.hansson@linaro.org>"); +MODULE_DESCRIPTION("ARM SCMI perf domain driver"); +MODULE_LICENSE("GPL v2"); |