aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pmdomain/arm/scmi_perf_domain.c
blob: d7ef46ccd9b8a414f8066f7fe2718f9867c89003 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
// SPDX-License-Identifier: GPL-2.0
/*
 * SCMI performance domain support.
 *
 * Copyright (C) 2023 Linaro Ltd.
 */

#include <linux/err.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/pm_domain.h>
#include <linux/pm_opp.h>
#include <linux/scmi_protocol.h>
#include <linux/slab.h>

struct scmi_perf_domain {
	struct generic_pm_domain genpd;
	const struct scmi_perf_proto_ops *perf_ops;
	const struct scmi_protocol_handle *ph;
	const struct scmi_perf_domain_info *info;
	u32 domain_id;
};

#define to_scmi_pd(pd) container_of(pd, struct scmi_perf_domain, genpd)

static int
scmi_pd_set_perf_state(struct generic_pm_domain *genpd, unsigned int state)
{
	struct scmi_perf_domain *pd = to_scmi_pd(genpd);
	int ret;

	if (!pd->info->set_perf)
		return 0;

	if (!state)
		return -EINVAL;

	ret = pd->perf_ops->level_set(pd->ph, pd->domain_id, state, false);
	if (ret)
		dev_warn(&genpd->dev, "Failed with %d when trying to set %d perf level",
			 ret, state);

	return ret;
}

static int
scmi_pd_attach_dev(struct generic_pm_domain *genpd, struct device *dev)
{
	struct scmi_perf_domain *pd = to_scmi_pd(genpd);
	int ret;

	/*
	 * Allow the device to be attached, but don't add the OPP table unless
	 * the performance level can be changed.
	 */
	if (!pd->info->set_perf)
		return 0;

	ret = pd->perf_ops->device_opps_add(pd->ph, dev, pd->domain_id);
	if (ret)
		dev_warn(dev, "failed to add OPPs for the device\n");

	return ret;
}

static void
scmi_pd_detach_dev(struct generic_pm_domain *genpd, struct device *dev)
{
	struct scmi_perf_domain *pd = to_scmi_pd(genpd);

	if (!pd->info->set_perf)
		return;

	dev_pm_opp_remove_all_dynamic(dev);
}

static int scmi_perf_domain_probe(struct scmi_device *sdev)
{
	struct device *dev = &sdev->dev;
	const struct scmi_handle *handle = sdev->handle;
	const struct scmi_perf_proto_ops *perf_ops;
	struct scmi_protocol_handle *ph;
	struct scmi_perf_domain *scmi_pd;
	struct genpd_onecell_data *scmi_pd_data;
	struct generic_pm_domain **domains;
	int num_domains, i, ret = 0;

	if (!handle)
		return -ENODEV;

	/* The OF node must specify us as a power-domain provider. */
	if (!of_find_property(dev->of_node, "#power-domain-cells", NULL))
		return 0;

	perf_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PERF, &ph);
	if (IS_ERR(perf_ops))
		return PTR_ERR(perf_ops);

	num_domains = perf_ops->num_domains_get(ph);
	if (num_domains < 0) {
		dev_warn(dev, "Failed with %d when getting num perf domains\n",
			 num_domains);
		return num_domains;
	} else if (!num_domains) {
		return 0;
	}

	scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL);
	if (!scmi_pd)
		return -ENOMEM;

	scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL);
	if (!scmi_pd_data)
		return -ENOMEM;

	domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL);
	if (!domains)
		return -ENOMEM;

	for (i = 0; i < num_domains; i++, scmi_pd++) {
		scmi_pd->info = perf_ops->info_get(ph, i);

		scmi_pd->domain_id = i;
		scmi_pd->perf_ops = perf_ops;
		scmi_pd->ph = ph;
		scmi_pd->genpd.name = scmi_pd->info->name;
		scmi_pd->genpd.flags = GENPD_FLAG_ALWAYS_ON |
				       GENPD_FLAG_OPP_TABLE_FW;
		scmi_pd->genpd.set_performance_state = scmi_pd_set_perf_state;
		scmi_pd->genpd.attach_dev = scmi_pd_attach_dev;
		scmi_pd->genpd.detach_dev = scmi_pd_detach_dev;

		ret = pm_genpd_init(&scmi_pd->genpd, NULL, false);
		if (ret)
			goto err;

		domains[i] = &scmi_pd->genpd;
	}

	scmi_pd_data->domains = domains;
	scmi_pd_data->num_domains = num_domains;

	ret = of_genpd_add_provider_onecell(dev->of_node, scmi_pd_data);
	if (ret)
		goto err;

	dev_set_drvdata(dev, scmi_pd_data);
	dev_info(dev, "Initialized %d performance domains", num_domains);
	return 0;
err:
	for (i--; i >= 0; i--)
		pm_genpd_remove(domains[i]);
	return ret;
}

static void scmi_perf_domain_remove(struct scmi_device *sdev)
{
	struct device *dev = &sdev->dev;
	struct genpd_onecell_data *scmi_pd_data = dev_get_drvdata(dev);
	int i;

	if (!scmi_pd_data)
		return;

	of_genpd_del_provider(dev->of_node);

	for (i = 0; i < scmi_pd_data->num_domains; i++)
		pm_genpd_remove(scmi_pd_data->domains[i]);
}

static const struct scmi_device_id scmi_id_table[] = {
	{ SCMI_PROTOCOL_PERF, "perf" },
	{ },
};
MODULE_DEVICE_TABLE(scmi, scmi_id_table);

static struct scmi_driver scmi_perf_domain_driver = {
	.name		= "scmi-perf-domain",
	.probe		= scmi_perf_domain_probe,
	.remove		= scmi_perf_domain_remove,
	.id_table	= scmi_id_table,
};
module_scmi_driver(scmi_perf_domain_driver);

MODULE_AUTHOR("Ulf Hansson <ulf.hansson@linaro.org>");
MODULE_DESCRIPTION("ARM SCMI perf domain driver");
MODULE_LICENSE("GPL v2");