LXR linux/drivers/soc/ti/ti_sci_pm

   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 */
  27struct 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 */
  44struct 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 */
  58static 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 */
  70static 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 */
  87static 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
 111static const struct of_device_id ti_sci_pm_domain_matches[] = {
 112        { .compatible = "ti,sci-pm-domain", },
 113        { },
 114};
 115MODULE_DEVICE_TABLE(of, ti_sci_pm_domain_matches);
 116
 117static 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
 196static 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};
 203module_platform_driver(ti_sci_pm_domains_driver);
 204MODULE_LICENSE("GPL v2");
 205MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver");
 206MODULE_AUTHOR("Dave Gerlach");
 207