1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * System Control and Management Interface (SCMI) Power Protocol
4 *
5 * Copyright (C) 2018 ARM Ltd.
6 */
7
8 #include "common.h"
9
10 enum scmi_power_protocol_cmd {
11 POWER_DOMAIN_ATTRIBUTES = 0x3,
12 POWER_STATE_SET = 0x4,
13 POWER_STATE_GET = 0x5,
14 POWER_STATE_NOTIFY = 0x6,
15 };
16
17 struct scmi_msg_resp_power_attributes {
18 __le16 num_domains;
19 __le16 reserved;
20 __le32 stats_addr_low;
21 __le32 stats_addr_high;
22 __le32 stats_size;
23 };
24
25 struct scmi_msg_resp_power_domain_attributes {
26 __le32 flags;
27 #define SUPPORTS_STATE_SET_NOTIFY(x) ((x) & BIT(31))
28 #define SUPPORTS_STATE_SET_ASYNC(x) ((x) & BIT(30))
29 #define SUPPORTS_STATE_SET_SYNC(x) ((x) & BIT(29))
30 u8 name[SCMI_MAX_STR_SIZE];
31 };
32
33 struct scmi_power_set_state {
34 __le32 flags;
35 #define STATE_SET_ASYNC BIT(0)
36 __le32 domain;
37 __le32 state;
38 };
39
40 struct scmi_power_state_notify {
41 __le32 domain;
42 __le32 notify_enable;
43 };
44
45 struct power_dom_info {
46 bool state_set_sync;
47 bool state_set_async;
48 bool state_set_notify;
49 char name[SCMI_MAX_STR_SIZE];
50 };
51
52 struct scmi_power_info {
53 int num_domains;
54 u64 stats_addr;
55 u32 stats_size;
56 struct power_dom_info *dom_info;
57 };
58
scmi_power_attributes_get(const struct scmi_handle * handle,struct scmi_power_info * pi)59 static int scmi_power_attributes_get(const struct scmi_handle *handle,
60 struct scmi_power_info *pi)
61 {
62 int ret;
63 struct scmi_xfer *t;
64 struct scmi_msg_resp_power_attributes *attr;
65
66 ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
67 SCMI_PROTOCOL_POWER, 0, sizeof(*attr), &t);
68 if (ret)
69 return ret;
70
71 attr = t->rx.buf;
72
73 ret = scmi_do_xfer(handle, t);
74 if (!ret) {
75 pi->num_domains = le16_to_cpu(attr->num_domains);
76 pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
77 (u64)le32_to_cpu(attr->stats_addr_high) << 32;
78 pi->stats_size = le32_to_cpu(attr->stats_size);
79 }
80
81 scmi_xfer_put(handle, t);
82 return ret;
83 }
84
85 static int
scmi_power_domain_attributes_get(const struct scmi_handle * handle,u32 domain,struct power_dom_info * dom_info)86 scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
87 struct power_dom_info *dom_info)
88 {
89 int ret;
90 struct scmi_xfer *t;
91 struct scmi_msg_resp_power_domain_attributes *attr;
92
93 ret = scmi_xfer_get_init(handle, POWER_DOMAIN_ATTRIBUTES,
94 SCMI_PROTOCOL_POWER, sizeof(domain),
95 sizeof(*attr), &t);
96 if (ret)
97 return ret;
98
99 put_unaligned_le32(domain, t->tx.buf);
100 attr = t->rx.buf;
101
102 ret = scmi_do_xfer(handle, t);
103 if (!ret) {
104 u32 flags = le32_to_cpu(attr->flags);
105
106 dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
107 dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
108 dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
109 strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
110 }
111
112 scmi_xfer_put(handle, t);
113 return ret;
114 }
115
116 static int
scmi_power_state_set(const struct scmi_handle * handle,u32 domain,u32 state)117 scmi_power_state_set(const struct scmi_handle *handle, u32 domain, u32 state)
118 {
119 int ret;
120 struct scmi_xfer *t;
121 struct scmi_power_set_state *st;
122
123 ret = scmi_xfer_get_init(handle, POWER_STATE_SET, SCMI_PROTOCOL_POWER,
124 sizeof(*st), 0, &t);
125 if (ret)
126 return ret;
127
128 st = t->tx.buf;
129 st->flags = cpu_to_le32(0);
130 st->domain = cpu_to_le32(domain);
131 st->state = cpu_to_le32(state);
132
133 ret = scmi_do_xfer(handle, t);
134
135 scmi_xfer_put(handle, t);
136 return ret;
137 }
138
139 static int
scmi_power_state_get(const struct scmi_handle * handle,u32 domain,u32 * state)140 scmi_power_state_get(const struct scmi_handle *handle, u32 domain, u32 *state)
141 {
142 int ret;
143 struct scmi_xfer *t;
144
145 ret = scmi_xfer_get_init(handle, POWER_STATE_GET, SCMI_PROTOCOL_POWER,
146 sizeof(u32), sizeof(u32), &t);
147 if (ret)
148 return ret;
149
150 put_unaligned_le32(domain, t->tx.buf);
151
152 ret = scmi_do_xfer(handle, t);
153 if (!ret)
154 *state = get_unaligned_le32(t->rx.buf);
155
156 scmi_xfer_put(handle, t);
157 return ret;
158 }
159
scmi_power_num_domains_get(const struct scmi_handle * handle)160 static int scmi_power_num_domains_get(const struct scmi_handle *handle)
161 {
162 struct scmi_power_info *pi = handle->power_priv;
163
164 return pi->num_domains;
165 }
166
scmi_power_name_get(const struct scmi_handle * handle,u32 domain)167 static char *scmi_power_name_get(const struct scmi_handle *handle, u32 domain)
168 {
169 struct scmi_power_info *pi = handle->power_priv;
170 struct power_dom_info *dom = pi->dom_info + domain;
171
172 return dom->name;
173 }
174
175 static struct scmi_power_ops power_ops = {
176 .num_domains_get = scmi_power_num_domains_get,
177 .name_get = scmi_power_name_get,
178 .state_set = scmi_power_state_set,
179 .state_get = scmi_power_state_get,
180 };
181
scmi_power_protocol_init(struct scmi_handle * handle)182 static int scmi_power_protocol_init(struct scmi_handle *handle)
183 {
184 int domain;
185 u32 version;
186 struct scmi_power_info *pinfo;
187
188 scmi_version_get(handle, SCMI_PROTOCOL_POWER, &version);
189
190 dev_dbg(handle->dev, "Power Version %d.%d\n",
191 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
192
193 pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
194 if (!pinfo)
195 return -ENOMEM;
196
197 scmi_power_attributes_get(handle, pinfo);
198
199 pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
200 sizeof(*pinfo->dom_info), GFP_KERNEL);
201 if (!pinfo->dom_info)
202 return -ENOMEM;
203
204 for (domain = 0; domain < pinfo->num_domains; domain++) {
205 struct power_dom_info *dom = pinfo->dom_info + domain;
206
207 scmi_power_domain_attributes_get(handle, domain, dom);
208 }
209
210 handle->power_ops = &power_ops;
211 handle->power_priv = pinfo;
212
213 return 0;
214 }
215
scmi_power_init(void)216 static int __init scmi_power_init(void)
217 {
218 return scmi_protocol_register(SCMI_PROTOCOL_POWER,
219 &scmi_power_protocol_init);
220 }
221 subsys_initcall(scmi_power_init);
222