drivers/firmware/arm_scmi/power.c

   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         u32 version;
  54         int num_domains;
  55         u64 stats_addr;
  56         u32 stats_size;
  57         struct power_dom_info *dom_info;
  58 };
  59
  60 static int scmi_power_attributes_get(const struct scmi_handle *handle,
  61                                      struct scmi_power_info *pi)
  62 {
  63         int ret;
  64         struct scmi_xfer *t;
  65         struct scmi_msg_resp_power_attributes *attr;
  66
  67         ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
  68                                  SCMI_PROTOCOL_POWER, 0, sizeof(*attr), &t);
  69         if (ret)
  70                 return ret;
  71
  72         attr = t->rx.buf;
  73
  74         ret = scmi_do_xfer(handle, t);
  75         if (!ret) {
  76                 pi->num_domains = le16_to_cpu(attr->num_domains);
  77                 pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
  78                                 (u64)le32_to_cpu(attr->stats_addr_high) << 32;
  79                 pi->stats_size = le32_to_cpu(attr->stats_size);
  80         }
  81
  82         scmi_xfer_put(handle, t);
  83         return ret;
  84 }
  85
  86 static int
  87 scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
  88                                  struct power_dom_info *dom_info)
  89 {
  90         int ret;
  91         struct scmi_xfer *t;
  92         struct scmi_msg_resp_power_domain_attributes *attr;
  93
  94         ret = scmi_xfer_get_init(handle, POWER_DOMAIN_ATTRIBUTES,
  95                                  SCMI_PROTOCOL_POWER, sizeof(domain),
  96                                  sizeof(*attr), &t);
  97         if (ret)
  98                 return ret;
  99
 100         put_unaligned_le32(domain, t->tx.buf);
 101         attr = t->rx.buf;
 102
 103         ret = scmi_do_xfer(handle, t);
 104         if (!ret) {
 105                 u32 flags = le32_to_cpu(attr->flags);
 106
 107                 dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
 108                 dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
 109                 dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
 110                 strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 111         }
 112
 113         scmi_xfer_put(handle, t);
 114         return ret;
 115 }
 116
 117 static int
 118 scmi_power_state_set(const struct scmi_handle *handle, u32 domain, u32 state)
 119 {
 120         int ret;
 121         struct scmi_xfer *t;
 122         struct scmi_power_set_state *st;
 123
 124         ret = scmi_xfer_get_init(handle, POWER_STATE_SET, SCMI_PROTOCOL_POWER,
 125                                  sizeof(*st), 0, &t);
 126         if (ret)
 127                 return ret;
 128
 129         st = t->tx.buf;
 130         st->flags = cpu_to_le32(0);
 131         st->domain = cpu_to_le32(domain);
 132         st->state = cpu_to_le32(state);
 133
 134         ret = scmi_do_xfer(handle, t);
 135
 136         scmi_xfer_put(handle, t);
 137         return ret;
 138 }
 139
 140 static int
 141 scmi_power_state_get(const struct scmi_handle *handle, u32 domain, u32 *state)
 142 {
 143         int ret;
 144         struct scmi_xfer *t;
 145
 146         ret = scmi_xfer_get_init(handle, POWER_STATE_GET, SCMI_PROTOCOL_POWER,
 147                                  sizeof(u32), sizeof(u32), &t);
 148         if (ret)
 149                 return ret;
 150
 151         put_unaligned_le32(domain, t->tx.buf);
 152
 153         ret = scmi_do_xfer(handle, t);
 154         if (!ret)
 155                 *state = get_unaligned_le32(t->rx.buf);
 156
 157         scmi_xfer_put(handle, t);
 158         return ret;
 159 }
 160
 161 static int scmi_power_num_domains_get(const struct scmi_handle *handle)
 162 {
 163         struct scmi_power_info *pi = handle->power_priv;
 164
 165         return pi->num_domains;
 166 }
 167
 168 static char *scmi_power_name_get(const struct scmi_handle *handle, u32 domain)
 169 {
 170         struct scmi_power_info *pi = handle->power_priv;
 171         struct power_dom_info *dom = pi->dom_info + domain;
 172
 173         return dom->name;
 174 }
 175
 176 static struct scmi_power_ops power_ops = {
 177         .num_domains_get = scmi_power_num_domains_get,
 178         .name_get = scmi_power_name_get,
 179         .state_set = scmi_power_state_set,
 180         .state_get = scmi_power_state_get,
 181 };
 182
 183 static int scmi_power_protocol_init(struct scmi_handle *handle)
 184 {
 185         int domain;
 186         u32 version;
 187         struct scmi_power_info *pinfo;
 188
 189         scmi_version_get(handle, SCMI_PROTOCOL_POWER, &version);
 190
 191         dev_dbg(handle->dev, "Power Version %d.%d\n",
 192                 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
 193
 194         pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
 195         if (!pinfo)
 196                 return -ENOMEM;
 197
 198         scmi_power_attributes_get(handle, pinfo);
 199
 200         pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
 201                                        sizeof(*pinfo->dom_info), GFP_KERNEL);
 202         if (!pinfo->dom_info)
 203                 return -ENOMEM;
 204
 205         for (domain = 0; domain < pinfo->num_domains; domain++) {
 206                 struct power_dom_info *dom = pinfo->dom_info + domain;
 207
 208                 scmi_power_domain_attributes_get(handle, domain, dom);
 209         }
 210
 211         pinfo->version = version;
 212         handle->power_ops = &power_ops;
 213         handle->power_priv = pinfo;
 214
 215         return 0;
 216 }
 217
 218 static int __init scmi_power_init(void)
 219 {
 220         return scmi_protocol_register(SCMI_PROTOCOL_POWER,
 221                                       &scmi_power_protocol_init);
 222 }
 223 subsys_initcall(scmi_power_init);