1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * System Control and Management Interface (SCMI) System Power Protocol
4 *
5 * Copyright (C) 2020-2022 ARM Ltd.
6 */
7
8 #define pr_fmt(fmt) "SCMI Notifications SYSTEM - " fmt
9
10 #include <linux/module.h>
11 #include <linux/scmi_protocol.h>
12
13 #include "protocols.h"
14 #include "notify.h"
15
16 /* Updated only after ALL the mandatory features for that version are merged */
17 #define SCMI_PROTOCOL_SUPPORTED_VERSION 0x20001
18
19 #define SCMI_SYSTEM_NUM_SOURCES 1
20
21 enum scmi_system_protocol_cmd {
22 SYSTEM_POWER_STATE_NOTIFY = 0x5,
23 };
24
25 struct scmi_system_power_state_notify {
26 __le32 notify_enable;
27 };
28
29 struct scmi_system_power_state_notifier_payld {
30 __le32 agent_id;
31 __le32 flags;
32 __le32 system_state;
33 __le32 timeout;
34 };
35
36 struct scmi_system_info {
37 u32 version;
38 bool graceful_timeout_supported;
39 bool power_state_notify_cmd;
40 };
41
scmi_system_notify_supported(const struct scmi_protocol_handle * ph,u8 evt_id,u32 src_id)42 static bool scmi_system_notify_supported(const struct scmi_protocol_handle *ph,
43 u8 evt_id, u32 src_id)
44 {
45 struct scmi_system_info *pinfo = ph->get_priv(ph);
46
47 if (evt_id != SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER)
48 return false;
49
50 return pinfo->power_state_notify_cmd;
51 }
52
scmi_system_request_notify(const struct scmi_protocol_handle * ph,bool enable)53 static int scmi_system_request_notify(const struct scmi_protocol_handle *ph,
54 bool enable)
55 {
56 int ret;
57 struct scmi_xfer *t;
58 struct scmi_system_power_state_notify *notify;
59
60 ret = ph->xops->xfer_get_init(ph, SYSTEM_POWER_STATE_NOTIFY,
61 sizeof(*notify), 0, &t);
62 if (ret)
63 return ret;
64
65 notify = t->tx.buf;
66 notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
67
68 ret = ph->xops->do_xfer(ph, t);
69
70 ph->xops->xfer_put(ph, t);
71 return ret;
72 }
73
scmi_system_set_notify_enabled(const struct scmi_protocol_handle * ph,u8 evt_id,u32 src_id,bool enable)74 static int scmi_system_set_notify_enabled(const struct scmi_protocol_handle *ph,
75 u8 evt_id, u32 src_id, bool enable)
76 {
77 int ret;
78
79 ret = scmi_system_request_notify(ph, enable);
80 if (ret)
81 pr_debug("FAIL_ENABLE - evt[%X] - ret:%d\n", evt_id, ret);
82
83 return ret;
84 }
85
86 static void *
scmi_system_fill_custom_report(const struct scmi_protocol_handle * ph,u8 evt_id,ktime_t timestamp,const void * payld,size_t payld_sz,void * report,u32 * src_id)87 scmi_system_fill_custom_report(const struct scmi_protocol_handle *ph,
88 u8 evt_id, ktime_t timestamp,
89 const void *payld, size_t payld_sz,
90 void *report, u32 *src_id)
91 {
92 size_t expected_sz;
93 const struct scmi_system_power_state_notifier_payld *p = payld;
94 struct scmi_system_power_state_notifier_report *r = report;
95 struct scmi_system_info *pinfo = ph->get_priv(ph);
96
97 expected_sz = pinfo->graceful_timeout_supported ?
98 sizeof(*p) : sizeof(*p) - sizeof(__le32);
99 if (evt_id != SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER ||
100 payld_sz != expected_sz)
101 return NULL;
102
103 r->timestamp = timestamp;
104 r->agent_id = le32_to_cpu(p->agent_id);
105 r->flags = le32_to_cpu(p->flags);
106 r->system_state = le32_to_cpu(p->system_state);
107 if (pinfo->graceful_timeout_supported &&
108 r->system_state == SCMI_SYSTEM_SHUTDOWN &&
109 SCMI_SYSPOWER_IS_REQUEST_GRACEFUL(r->flags))
110 r->timeout = le32_to_cpu(p->timeout);
111 else
112 r->timeout = 0x00;
113 *src_id = 0;
114
115 return r;
116 }
117
118 static const struct scmi_event system_events[] = {
119 {
120 .id = SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER,
121 .max_payld_sz =
122 sizeof(struct scmi_system_power_state_notifier_payld),
123 .max_report_sz =
124 sizeof(struct scmi_system_power_state_notifier_report),
125 },
126 };
127
128 static const struct scmi_event_ops system_event_ops = {
129 .is_notify_supported = scmi_system_notify_supported,
130 .set_notify_enabled = scmi_system_set_notify_enabled,
131 .fill_custom_report = scmi_system_fill_custom_report,
132 };
133
134 static const struct scmi_protocol_events system_protocol_events = {
135 .queue_sz = SCMI_PROTO_QUEUE_SZ,
136 .ops = &system_event_ops,
137 .evts = system_events,
138 .num_events = ARRAY_SIZE(system_events),
139 .num_sources = SCMI_SYSTEM_NUM_SOURCES,
140 };
141
scmi_system_protocol_init(const struct scmi_protocol_handle * ph)142 static int scmi_system_protocol_init(const struct scmi_protocol_handle *ph)
143 {
144 int ret;
145 u32 version;
146 struct scmi_system_info *pinfo;
147
148 ret = ph->xops->version_get(ph, &version);
149 if (ret)
150 return ret;
151
152 dev_dbg(ph->dev, "System Power Version %d.%d\n",
153 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
154
155 pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
156 if (!pinfo)
157 return -ENOMEM;
158
159 pinfo->version = version;
160 if (PROTOCOL_REV_MAJOR(pinfo->version) >= 0x2)
161 pinfo->graceful_timeout_supported = true;
162
163 if (!ph->hops->protocol_msg_check(ph, SYSTEM_POWER_STATE_NOTIFY, NULL))
164 pinfo->power_state_notify_cmd = true;
165
166 return ph->set_priv(ph, pinfo, version);
167 }
168
169 static const struct scmi_protocol scmi_system = {
170 .id = SCMI_PROTOCOL_SYSTEM,
171 .owner = THIS_MODULE,
172 .instance_init = &scmi_system_protocol_init,
173 .ops = NULL,
174 .events = &system_protocol_events,
175 .supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
176 };
177
178 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(system, scmi_system)
179