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					const 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 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
129static 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					of_node_put(np);
176					return -ENOMEM;
177				}
178
179				pd->pd.name = devm_kasprintf(dev, GFP_KERNEL,
180							     "pd:%d",
181							     args.args[0]);
182				if (!pd->pd.name) {
183					of_node_put(np);
184					return -ENOMEM;
185				}
186
187				pd->pd.power_off = ti_sci_pd_power_off;
188				pd->pd.power_on = ti_sci_pd_power_on;
189				pd->idx = args.args[0];
190				pd->parent = pd_provider;
191
192				pm_genpd_init(&pd->pd, NULL, true);
193
194				list_add(&pd->node, &pd_provider->pd_list);
195			}
196			index++;
197		}
198	}
199
200	pd_provider->data.domains =
201		devm_kcalloc(dev, max_id + 1,
202			     sizeof(*pd_provider->data.domains),
203			     GFP_KERNEL);
204	if (!pd_provider->data.domains)
205		return -ENOMEM;
206
207	pd_provider->data.num_domains = max_id + 1;
208	pd_provider->data.xlate = ti_sci_pd_xlate;
209
210	list_for_each_entry(pd, &pd_provider->pd_list, node)
211		pd_provider->data.domains[pd->idx] = &pd->pd;
212
213	return of_genpd_add_provider_onecell(dev->of_node, &pd_provider->data);
214}
215
216static struct platform_driver ti_sci_pm_domains_driver = {
217	.probe = ti_sci_pm_domain_probe,
218	.driver = {
219		.name = "ti_sci_pm_domains",
220		.of_match_table = ti_sci_pm_domain_matches,
221	},
222};
223module_platform_driver(ti_sci_pm_domains_driver);
224MODULE_LICENSE("GPL v2");
225MODULE_DESCRIPTION("TI System Control Interface (SCI) Power Domain driver");
226MODULE_AUTHOR("Dave Gerlach");
227