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_idx_exists(struct ti_sci_genpd_provider * pd_provider,u32 idx)117 static bool ti_sci_pm_idx_exists(struct ti_sci_genpd_provider *pd_provider, u32 idx)
118 {
119 struct ti_sci_pm_domain *pd;
120
121 list_for_each_entry(pd, &pd_provider->pd_list, node) {
122 if (pd->idx == idx)
123 return true;
124 }
125
126 return false;
127 }
128
ti_sci_pm_domain_probe(struct platform_device * pdev)129 static int ti_sci_pm_domain_probe(struct platform_device *pdev)
130 {
131 struct device *dev = &pdev->dev;
132 struct ti_sci_genpd_provider *pd_provider;
133 struct ti_sci_pm_domain *pd;
134 struct device_node *np;
135 struct of_phandle_args args;
136 int ret;
137 u32 max_id = 0;
138 int index;
139
140 pd_provider = devm_kzalloc(dev, sizeof(*pd_provider), GFP_KERNEL);
141 if (!pd_provider)
142 return -ENOMEM;
143
144 pd_provider->ti_sci = devm_ti_sci_get_handle(dev);
145 if (IS_ERR(pd_provider->ti_sci))
146 return PTR_ERR(pd_provider->ti_sci);
147
148 pd_provider->dev = dev;
149
150 INIT_LIST_HEAD(&pd_provider->pd_list);
151
152 /* Find highest device ID used for power domains */
153 for_each_node_with_property(np, "power-domains") {
154 index = 0;
155
156 while (1) {
157 ret = of_parse_phandle_with_args(np, "power-domains",
158 "#power-domain-cells",
159 index, &args);
160 if (ret)
161 break;
162
163 if (args.args_count >= 1 && args.np == dev->of_node) {
164 if (args.args[0] > max_id) {
165 max_id = args.args[0];
166 } else {
167 if (ti_sci_pm_idx_exists(pd_provider, args.args[0])) {
168 index++;
169 continue;
170 }
171 }
172
173 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
174 if (!pd)
175 return -ENOMEM;
176
177 pd->pd.name = devm_kasprintf(dev, GFP_KERNEL,
178 "pd:%d",
179 args.args[0]);
180 if (!pd->pd.name)
181 return -ENOMEM;
182
183 pd->pd.power_off = ti_sci_pd_power_off;
184 pd->pd.power_on = ti_sci_pd_power_on;
185 pd->idx = args.args[0];
186 pd->parent = pd_provider;
187
188 pm_genpd_init(&pd->pd, NULL, true);
189
190 list_add(&pd->node, &pd_provider->pd_list);
191 }
192 index++;
193 }
194 }
195
196 pd_provider->data.domains =
197 devm_kcalloc(dev, max_id + 1,
198 sizeof(*pd_provider->data.domains),
199 GFP_KERNEL);
200 if (!pd_provider->data.domains)
201 return -ENOMEM;
202
203 pd_provider->data.num_domains = max_id + 1;
204 pd_provider->data.xlate = ti_sci_pd_xlate;
205
206 list_for_each_entry(pd, &pd_provider->pd_list, node)
207 pd_provider->data.domains[pd->idx] = &pd->pd;
208
209 return of_genpd_add_provider_onecell(dev->of_node, &pd_provider->data);
210 }
211
212 static struct platform_driver ti_sci_pm_domains_driver = {
213 .probe = ti_sci_pm_domain_probe,
214 .driver = {
215 .name = "ti_sci_pm_domains",
216 .of_match_table = ti_sci_pm_domain_matches,
217 },
218 };
219 module_platform_driver(ti_sci_pm_domains_driver);
220 MODULE_LICENSE("GPL v2");
221 MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver");
222 MODULE_AUTHOR("Dave Gerlach");
223