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 */
ti_sci_pd_power_off(struct generic_pm_domain * domain)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 */
ti_sci_pd_power_on(struct generic_pm_domain * domain)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 */
ti_sci_pd_xlate(struct of_phandle_args * genpdspec,void * data)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
ti_sci_pm_domain_probe(struct platform_device * pdev)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;
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 for_each_node_with_property(np, "power-domains") {
142 index = 0;
143
144 while (1) {
145 ret = of_parse_phandle_with_args(np, "power-domains",
146 "#power-domain-cells",
147 index, &args);
148 if (ret)
149 break;
150
151 if (args.args_count >= 1 && args.np == dev->of_node) {
152 if (args.args[0] > max_id)
153 max_id = args.args[0];
154
155 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
156 if (!pd)
157 return -ENOMEM;
158
159 pd->pd.name = devm_kasprintf(dev, GFP_KERNEL,
160 "pd:%d",
161 args.args[0]);
162 if (!pd->pd.name)
163 return -ENOMEM;
164
165 pd->pd.power_off = ti_sci_pd_power_off;
166 pd->pd.power_on = ti_sci_pd_power_on;
167 pd->idx = args.args[0];
168 pd->parent = pd_provider;
169
170 pm_genpd_init(&pd->pd, NULL, true);
171
172 list_add(&pd->node, &pd_provider->pd_list);
173 }
174 index++;
175 }
176 }
177
178 pd_provider->data.domains =
179 devm_kcalloc(dev, max_id + 1,
180 sizeof(*pd_provider->data.domains),
181 GFP_KERNEL);
182 if (!pd_provider->data.domains)
183 return -ENOMEM;
184
185 pd_provider->data.num_domains = max_id + 1;
186 pd_provider->data.xlate = ti_sci_pd_xlate;
187
188 list_for_each_entry(pd, &pd_provider->pd_list, node)
189 pd_provider->data.domains[pd->idx] = &pd->pd;
190
191 return of_genpd_add_provider_onecell(dev->of_node, &pd_provider->data);
192 }
193
194 static struct platform_driver ti_sci_pm_domains_driver = {
195 .probe = ti_sci_pm_domain_probe,
196 .driver = {
197 .name = "ti_sci_pm_domains",
198 .of_match_table = ti_sci_pm_domain_matches,
199 },
200 };
201 module_platform_driver(ti_sci_pm_domains_driver);
202 MODULE_LICENSE("GPL v2");
203 MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver");
204 MODULE_AUTHOR("Dave Gerlach");
205
