1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * System Control and Management Interface (SCMI) System Power Protocol
  4 *
  5 * Copyright (C) 2020-2021 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 "common.h"
 14#include "notify.h"
 15
 16#define SCMI_SYSTEM_NUM_SOURCES		1
 17
 18enum scmi_system_protocol_cmd {
 19	SYSTEM_POWER_STATE_NOTIFY = 0x5,
 20};
 21
 22struct scmi_system_power_state_notify {
 23	__le32 notify_enable;
 24};
 25
 26struct scmi_system_power_state_notifier_payld {
 27	__le32 agent_id;
 28	__le32 flags;
 29	__le32 system_state;
 30};
 31
 32struct scmi_system_info {
 33	u32 version;
 34};
 35
 36static int scmi_system_request_notify(const struct scmi_protocol_handle *ph,
 37				      bool enable)
 38{
 39	int ret;
 40	struct scmi_xfer *t;
 41	struct scmi_system_power_state_notify *notify;
 42
 43	ret = ph->xops->xfer_get_init(ph, SYSTEM_POWER_STATE_NOTIFY,
 44				      sizeof(*notify), 0, &t);
 45	if (ret)
 46		return ret;
 47
 48	notify = t->tx.buf;
 49	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
 50
 51	ret = ph->xops->do_xfer(ph, t);
 52
 53	ph->xops->xfer_put(ph, t);
 54	return ret;
 55}
 56
 57static int scmi_system_set_notify_enabled(const struct scmi_protocol_handle *ph,
 58					  u8 evt_id, u32 src_id, bool enable)
 59{
 60	int ret;
 61
 62	ret = scmi_system_request_notify(ph, enable);
 63	if (ret)
 64		pr_debug("FAIL_ENABLE - evt[%X] - ret:%d\n", evt_id, ret);
 65
 66	return ret;
 67}
 68
 69static void *
 70scmi_system_fill_custom_report(const struct scmi_protocol_handle *ph,
 71			       u8 evt_id, ktime_t timestamp,
 72			       const void *payld, size_t payld_sz,
 73			       void *report, u32 *src_id)
 74{
 75	const struct scmi_system_power_state_notifier_payld *p = payld;
 76	struct scmi_system_power_state_notifier_report *r = report;
 77
 78	if (evt_id != SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER ||
 79	    sizeof(*p) != payld_sz)
 80		return NULL;
 81
 82	r->timestamp = timestamp;
 83	r->agent_id = le32_to_cpu(p->agent_id);
 84	r->flags = le32_to_cpu(p->flags);
 85	r->system_state = le32_to_cpu(p->system_state);
 86	*src_id = 0;
 87
 88	return r;
 89}
 90
 91static const struct scmi_event system_events[] = {
 92	{
 93		.id = SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER,
 94		.max_payld_sz =
 95			sizeof(struct scmi_system_power_state_notifier_payld),
 96		.max_report_sz =
 97			sizeof(struct scmi_system_power_state_notifier_report),
 98	},
 99};
100
101static const struct scmi_event_ops system_event_ops = {
102	.set_notify_enabled = scmi_system_set_notify_enabled,
103	.fill_custom_report = scmi_system_fill_custom_report,
104};
105
106static const struct scmi_protocol_events system_protocol_events = {
107	.queue_sz = SCMI_PROTO_QUEUE_SZ,
108	.ops = &system_event_ops,
109	.evts = system_events,
110	.num_events = ARRAY_SIZE(system_events),
111	.num_sources = SCMI_SYSTEM_NUM_SOURCES,
112};
113
114static int scmi_system_protocol_init(const struct scmi_protocol_handle *ph)
115{
116	u32 version;
117	struct scmi_system_info *pinfo;
118
119	ph->xops->version_get(ph, &version);
120
121	dev_dbg(ph->dev, "System Power Version %d.%d\n",
122		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
123
124	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
125	if (!pinfo)
126		return -ENOMEM;
127
128	pinfo->version = version;
129	return ph->set_priv(ph, pinfo);
130}
131
132static const struct scmi_protocol scmi_system = {
133	.id = SCMI_PROTOCOL_SYSTEM,
134	.owner = THIS_MODULE,
135	.instance_init = &scmi_system_protocol_init,
136	.ops = NULL,
137	.events = &system_protocol_events,
138};
139
140DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(system, scmi_system)