drivers/soc/ti/ti_sci_pm_domains.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * TI SCI Generic Power Domain Driver
   4  *
   5  * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
   6  *      J Keerthy <j-keerthy@ti.com>
   7  *      Dave Gerlach <d-gerlach@ti.com>
   8  */
   9
  10 #include <linux/err.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/pm_domain.h>
  15 #include <linux/slab.h>
  16 #include <linux/soc/ti/ti_sci_protocol.h>
  17 #include <dt-bindings/soc/ti,sci_pm_domain.h>
  18
  19 /**
  20  * struct ti_sci_genpd_provider: holds common TI SCI genpd provider data
  21  * @ti_sci: handle to TI SCI protocol driver that provides ops to
  22  *          communicate with system control processor.
  23  * @dev: pointer to dev for the driver for devm allocs
  24  * @pd_list: list of all the power domains on the device
  25  * @data: onecell data for genpd core
  26  */
  27 struct ti_sci_genpd_provider {
  28         const struct ti_sci_handle *ti_sci;
  29         struct device *dev;
  30         struct list_head pd_list;
  31         struct genpd_onecell_data data;
  32 };
  33
  34 /**
  35  * struct ti_sci_pm_domain: TI specific data needed for power domain
  36  * @idx: index of the device that identifies it with the system
  37  *       control processor.
  38  * @exclusive: Permissions for exclusive request or shared request of the
  39  *             device.
  40  * @pd: generic_pm_domain for use with the genpd framework
  41  * @node: link for the genpd list
  42  * @parent: link to the parent TI SCI genpd provider
  43  */
  44 struct ti_sci_pm_domain {
  45         int idx;
  46         u8 exclusive;
  47         struct generic_pm_domain pd;
  48         struct list_head node;
  49         struct ti_sci_genpd_provider *parent;
  50 };
  51
  52 #define genpd_to_ti_sci_pd(gpd) container_of(gpd, struct ti_sci_pm_domain, pd)
  53
  54 /*
  55  * ti_sci_pd_power_off(): genpd power down hook
  56  * @domain: pointer to the powerdomain to power off
  57  */
  58 static int ti_sci_pd_power_off(struct generic_pm_domain *domain)
  59 {
  60         struct ti_sci_pm_domain *pd = genpd_to_ti_sci_pd(domain);
  61         const struct ti_sci_handle *ti_sci = pd->parent->ti_sci;
  62
  63         return ti_sci->ops.dev_ops.put_device(ti_sci, pd->idx);
  64 }
  65
  66 /*
  67  * ti_sci_pd_power_on(): genpd power up hook
  68  * @domain: pointer to the powerdomain to power on
  69  */
  70 static int ti_sci_pd_power_on(struct generic_pm_domain *domain)
  71 {
  72         struct ti_sci_pm_domain *pd = genpd_to_ti_sci_pd(domain);
  73         const struct ti_sci_handle *ti_sci = pd->parent->ti_sci;
  74
  75         if (pd->exclusive)
  76                 return ti_sci->ops.dev_ops.get_device_exclusive(ti_sci,
  77                                                                 pd->idx);
  78         else
  79                 return ti_sci->ops.dev_ops.get_device(ti_sci, pd->idx);
  80 }
  81
  82 /*
  83  * ti_sci_pd_xlate(): translation service for TI SCI genpds
  84  * @genpdspec: DT identification data for the genpd
  85  * @data: genpd core data for all the powerdomains on the device
  86  */
  87 static struct generic_pm_domain *ti_sci_pd_xlate(
  88                                         struct of_phandle_args *genpdspec,
  89                                         void *data)
  90 {
  91         struct genpd_onecell_data *genpd_data = data;
  92         unsigned int idx = genpdspec->args[0];
  93
  94         if (genpdspec->args_count != 1 && genpdspec->args_count != 2)
  95                 return ERR_PTR(-EINVAL);
  96
  97         if (idx >= genpd_data->num_domains) {
  98                 pr_err("%s: invalid domain index %u\n", __func__, idx);
  99                 return ERR_PTR(-EINVAL);
 100         }
 101
 102         if (!genpd_data->domains[idx])
 103                 return ERR_PTR(-ENOENT);
 104
 105         genpd_to_ti_sci_pd(genpd_data->domains[idx])->exclusive =
 106                 genpdspec->args[1];
 107
 108         return genpd_data->domains[idx];
 109 }
 110
 111 static const struct of_device_id ti_sci_pm_domain_matches[] = {
 112         { .compatible = "ti,sci-pm-domain", },
 113         { },
 114 };
 115 MODULE_DEVICE_TABLE(of, ti_sci_pm_domain_matches);
 116
 117 static int ti_sci_pm_domain_probe(struct platform_device *pdev)
 118 {
 119         struct device *dev = &pdev->dev;
 120         struct ti_sci_genpd_provider *pd_provider;
 121         struct ti_sci_pm_domain *pd;
 122         struct device_node *np = NULL;
 123         struct of_phandle_args args;
 124         int ret;
 125         u32 max_id = 0;
 126         int index;
 127
 128         pd_provider = devm_kzalloc(dev, sizeof(*pd_provider), GFP_KERNEL);
 129         if (!pd_provider)
 130                 return -ENOMEM;
 131
 132         pd_provider->ti_sci = devm_ti_sci_get_handle(dev);
 133         if (IS_ERR(pd_provider->ti_sci))
 134                 return PTR_ERR(pd_provider->ti_sci);
 135
 136         pd_provider->dev = dev;
 137
 138         INIT_LIST_HEAD(&pd_provider->pd_list);
 139
 140         /* Find highest device ID used for power domains */
 141         while (1) {
 142                 np = of_find_node_with_property(np, "power-domains");
 143                 if (!np)
 144                         break;
 145
 146                 index = 0;
 147
 148                 while (1) {
 149                         ret = of_parse_phandle_with_args(np, "power-domains",
 150                                                          "#power-domain-cells",
 151                                                          index, &args);
 152                         if (ret)
 153                                 break;
 154
 155                         if (args.args_count >= 1 && args.np == dev->of_node) {
 156                                 if (args.args[0] > max_id)
 157                                         max_id = args.args[0];
 158
 159                                 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
 160                                 if (!pd)
 161                                         return -ENOMEM;
 162
 163                                 pd->pd.name = devm_kasprintf(dev, GFP_KERNEL,
 164                                                              "pd:%d",
 165                                                              args.args[0]);
 166                                 if (!pd->pd.name)
 167                                         return -ENOMEM;
 168
 169                                 pd->pd.power_off = ti_sci_pd_power_off;
 170                                 pd->pd.power_on = ti_sci_pd_power_on;
 171                                 pd->idx = args.args[0];
 172                                 pd->parent = pd_provider;
 173
 174                                 pm_genpd_init(&pd->pd, NULL, true);
 175
 176                                 list_add(&pd->node, &pd_provider->pd_list);
 177                         }
 178                         index++;
 179                 }
 180         }
 181
 182         pd_provider->data.domains =
 183                 devm_kcalloc(dev, max_id + 1,
 184                              sizeof(*pd_provider->data.domains),
 185                              GFP_KERNEL);
 186
 187         pd_provider->data.num_domains = max_id + 1;
 188         pd_provider->data.xlate = ti_sci_pd_xlate;
 189
 190         list_for_each_entry(pd, &pd_provider->pd_list, node)
 191                 pd_provider->data.domains[pd->idx] = &pd->pd;
 192
 193         return of_genpd_add_provider_onecell(dev->of_node, &pd_provider->data);
 194 }
 195
 196 static struct platform_driver ti_sci_pm_domains_driver = {
 197         .probe = ti_sci_pm_domain_probe,
 198         .driver = {
 199                 .name = "ti_sci_pm_domains",
 200                 .of_match_table = ti_sci_pm_domain_matches,
 201         },
 202 };
 203 module_platform_driver(ti_sci_pm_domains_driver);
 204 MODULE_LICENSE("GPL v2");
 205 MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver");
 206 MODULE_AUTHOR("Dave Gerlach");