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 #define SCMI_SYSTEM_NUM_SOURCES 1 17 18 enum scmi_system_protocol_cmd { 19 SYSTEM_POWER_STATE_NOTIFY = 0x5, 20 }; 21 22 struct scmi_system_power_state_notify { 23 __le32 notify_enable; 24 }; 25 26 struct scmi_system_power_state_notifier_payld { 27 __le32 agent_id; 28 __le32 flags; 29 __le32 system_state; 30 __le32 timeout; 31 }; 32 33 struct scmi_system_info { 34 u32 version; 35 bool graceful_timeout_supported; 36 }; 37 38 static int scmi_system_request_notify(const struct scmi_protocol_handle *ph, 39 bool enable) 40 { 41 int ret; 42 struct scmi_xfer *t; 43 struct scmi_system_power_state_notify *notify; 44 45 ret = ph->xops->xfer_get_init(ph, SYSTEM_POWER_STATE_NOTIFY, 46 sizeof(*notify), 0, &t); 47 if (ret) 48 return ret; 49 50 notify = t->tx.buf; 51 notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0; 52 53 ret = ph->xops->do_xfer(ph, t); 54 55 ph->xops->xfer_put(ph, t); 56 return ret; 57 } 58 59 static int scmi_system_set_notify_enabled(const struct scmi_protocol_handle *ph, 60 u8 evt_id, u32 src_id, bool enable) 61 { 62 int ret; 63 64 ret = scmi_system_request_notify(ph, enable); 65 if (ret) 66 pr_debug("FAIL_ENABLE - evt[%X] - ret:%d\n", evt_id, ret); 67 68 return ret; 69 } 70 71 static void * 72 scmi_system_fill_custom_report(const struct scmi_protocol_handle *ph, 73 u8 evt_id, ktime_t timestamp, 74 const void *payld, size_t payld_sz, 75 void *report, u32 *src_id) 76 { 77 size_t expected_sz; 78 const struct scmi_system_power_state_notifier_payld *p = payld; 79 struct scmi_system_power_state_notifier_report *r = report; 80 struct scmi_system_info *pinfo = ph->get_priv(ph); 81 82 expected_sz = pinfo->graceful_timeout_supported ? 83 sizeof(*p) : sizeof(*p) - sizeof(__le32); 84 if (evt_id != SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER || 85 payld_sz != expected_sz) 86 return NULL; 87 88 r->timestamp = timestamp; 89 r->agent_id = le32_to_cpu(p->agent_id); 90 r->flags = le32_to_cpu(p->flags); 91 r->system_state = le32_to_cpu(p->system_state); 92 if (pinfo->graceful_timeout_supported && 93 r->system_state == SCMI_SYSTEM_SHUTDOWN && 94 SCMI_SYSPOWER_IS_REQUEST_GRACEFUL(r->flags)) 95 r->timeout = le32_to_cpu(p->timeout); 96 else 97 r->timeout = 0x00; 98 *src_id = 0; 99 100 return r; 101 } 102 103 static const struct scmi_event system_events[] = { 104 { 105 .id = SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER, 106 .max_payld_sz = 107 sizeof(struct scmi_system_power_state_notifier_payld), 108 .max_report_sz = 109 sizeof(struct scmi_system_power_state_notifier_report), 110 }, 111 }; 112 113 static const struct scmi_event_ops system_event_ops = { 114 .set_notify_enabled = scmi_system_set_notify_enabled, 115 .fill_custom_report = scmi_system_fill_custom_report, 116 }; 117 118 static const struct scmi_protocol_events system_protocol_events = { 119 .queue_sz = SCMI_PROTO_QUEUE_SZ, 120 .ops = &system_event_ops, 121 .evts = system_events, 122 .num_events = ARRAY_SIZE(system_events), 123 .num_sources = SCMI_SYSTEM_NUM_SOURCES, 124 }; 125 126 static int scmi_system_protocol_init(const struct scmi_protocol_handle *ph) 127 { 128 int ret; 129 u32 version; 130 struct scmi_system_info *pinfo; 131 132 ret = ph->xops->version_get(ph, &version); 133 if (ret) 134 return ret; 135 136 dev_dbg(ph->dev, "System Power Version %d.%d\n", 137 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version)); 138 139 pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL); 140 if (!pinfo) 141 return -ENOMEM; 142 143 pinfo->version = version; 144 if (PROTOCOL_REV_MAJOR(pinfo->version) >= 0x2) 145 pinfo->graceful_timeout_supported = true; 146 147 return ph->set_priv(ph, pinfo); 148 } 149 150 static const struct scmi_protocol scmi_system = { 151 .id = SCMI_PROTOCOL_SYSTEM, 152 .owner = THIS_MODULE, 153 .instance_init = &scmi_system_protocol_init, 154 .ops = NULL, 155 .events = &system_protocol_events, 156 }; 157 158 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(system, scmi_system) 159