drivers/firmware/arm_scmi/reset.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * System Control and Management Interface (SCMI) Reset Protocol
   4  *
   5  * Copyright (C) 2019 ARM Ltd.
   6  */
   7
   8 #define pr_fmt(fmt) "SCMI Notifications RESET - " fmt
   9
  10 #include <linux/scmi_protocol.h>
  11
  12 #include "common.h"
  13 #include "notify.h"
  14
  15 enum scmi_reset_protocol_cmd {
  16         RESET_DOMAIN_ATTRIBUTES = 0x3,
  17         RESET = 0x4,
  18         RESET_NOTIFY = 0x5,
  19 };
  20
  21 #define NUM_RESET_DOMAIN_MASK   0xffff
  22 #define RESET_NOTIFY_ENABLE     BIT(0)
  23
  24 struct scmi_msg_resp_reset_domain_attributes {
  25         __le32 attributes;
  26 #define SUPPORTS_ASYNC_RESET(x)         ((x) & BIT(31))
  27 #define SUPPORTS_NOTIFY_RESET(x)        ((x) & BIT(30))
  28         __le32 latency;
  29             u8 name[SCMI_MAX_STR_SIZE];
  30 };
  31
  32 struct scmi_msg_reset_domain_reset {
  33         __le32 domain_id;
  34         __le32 flags;
  35 #define AUTONOMOUS_RESET        BIT(0)
  36 #define EXPLICIT_RESET_ASSERT   BIT(1)
  37 #define ASYNCHRONOUS_RESET      BIT(2)
  38         __le32 reset_state;
  39 #define ARCH_COLD_RESET         0
  40 };
  41
  42 struct scmi_msg_reset_notify {
  43         __le32 id;
  44         __le32 event_control;
  45 #define RESET_TP_NOTIFY_ALL     BIT(0)
  46 };
  47
  48 struct scmi_reset_issued_notify_payld {
  49         __le32 agent_id;
  50         __le32 domain_id;
  51         __le32 reset_state;
  52 };
  53
  54 struct reset_dom_info {
  55         bool async_reset;
  56         bool reset_notify;
  57         u32 latency_us;
  58         char name[SCMI_MAX_STR_SIZE];
  59 };
  60
  61 struct scmi_reset_info {
  62         u32 version;
  63         int num_domains;
  64         struct reset_dom_info *dom_info;
  65 };
  66
  67 static int scmi_reset_attributes_get(const struct scmi_handle *handle,
  68                                      struct scmi_reset_info *pi)
  69 {
  70         int ret;
  71         struct scmi_xfer *t;
  72         u32 attr;
  73
  74         ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
  75                                  SCMI_PROTOCOL_RESET, 0, sizeof(attr), &t);
  76         if (ret)
  77                 return ret;
  78
  79         ret = scmi_do_xfer(handle, t);
  80         if (!ret) {
  81                 attr = get_unaligned_le32(t->rx.buf);
  82                 pi->num_domains = attr & NUM_RESET_DOMAIN_MASK;
  83         }
  84
  85         scmi_xfer_put(handle, t);
  86         return ret;
  87 }
  88
  89 static int
  90 scmi_reset_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
  91                                  struct reset_dom_info *dom_info)
  92 {
  93         int ret;
  94         struct scmi_xfer *t;
  95         struct scmi_msg_resp_reset_domain_attributes *attr;
  96
  97         ret = scmi_xfer_get_init(handle, RESET_DOMAIN_ATTRIBUTES,
  98                                  SCMI_PROTOCOL_RESET, sizeof(domain),
  99                                  sizeof(*attr), &t);
 100         if (ret)
 101                 return ret;
 102
 103         put_unaligned_le32(domain, t->tx.buf);
 104         attr = t->rx.buf;
 105
 106         ret = scmi_do_xfer(handle, t);
 107         if (!ret) {
 108                 u32 attributes = le32_to_cpu(attr->attributes);
 109
 110                 dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
 111                 dom_info->reset_notify = SUPPORTS_NOTIFY_RESET(attributes);
 112                 dom_info->latency_us = le32_to_cpu(attr->latency);
 113                 if (dom_info->latency_us == U32_MAX)
 114                         dom_info->latency_us = 0;
 115                 strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 116         }
 117
 118         scmi_xfer_put(handle, t);
 119         return ret;
 120 }
 121
 122 static int scmi_reset_num_domains_get(const struct scmi_handle *handle)
 123 {
 124         struct scmi_reset_info *pi = handle->reset_priv;
 125
 126         return pi->num_domains;
 127 }
 128
 129 static char *scmi_reset_name_get(const struct scmi_handle *handle, u32 domain)
 130 {
 131         struct scmi_reset_info *pi = handle->reset_priv;
 132         struct reset_dom_info *dom = pi->dom_info + domain;
 133
 134         return dom->name;
 135 }
 136
 137 static int scmi_reset_latency_get(const struct scmi_handle *handle, u32 domain)
 138 {
 139         struct scmi_reset_info *pi = handle->reset_priv;
 140         struct reset_dom_info *dom = pi->dom_info + domain;
 141
 142         return dom->latency_us;
 143 }
 144
 145 static int scmi_domain_reset(const struct scmi_handle *handle, u32 domain,
 146                              u32 flags, u32 state)
 147 {
 148         int ret;
 149         struct scmi_xfer *t;
 150         struct scmi_msg_reset_domain_reset *dom;
 151         struct scmi_reset_info *pi = handle->reset_priv;
 152         struct reset_dom_info *rdom = pi->dom_info + domain;
 153
 154         if (rdom->async_reset)
 155                 flags |= ASYNCHRONOUS_RESET;
 156
 157         ret = scmi_xfer_get_init(handle, RESET, SCMI_PROTOCOL_RESET,
 158                                  sizeof(*dom), 0, &t);
 159         if (ret)
 160                 return ret;
 161
 162         dom = t->tx.buf;
 163         dom->domain_id = cpu_to_le32(domain);
 164         dom->flags = cpu_to_le32(flags);
 165         dom->reset_state = cpu_to_le32(state);
 166
 167         if (rdom->async_reset)
 168                 ret = scmi_do_xfer_with_response(handle, t);
 169         else
 170                 ret = scmi_do_xfer(handle, t);
 171
 172         scmi_xfer_put(handle, t);
 173         return ret;
 174 }
 175
 176 static int scmi_reset_domain_reset(const struct scmi_handle *handle, u32 domain)
 177 {
 178         return scmi_domain_reset(handle, domain, AUTONOMOUS_RESET,
 179                                  ARCH_COLD_RESET);
 180 }
 181
 182 static int
 183 scmi_reset_domain_assert(const struct scmi_handle *handle, u32 domain)
 184 {
 185         return scmi_domain_reset(handle, domain, EXPLICIT_RESET_ASSERT,
 186                                  ARCH_COLD_RESET);
 187 }
 188
 189 static int
 190 scmi_reset_domain_deassert(const struct scmi_handle *handle, u32 domain)
 191 {
 192         return scmi_domain_reset(handle, domain, 0, ARCH_COLD_RESET);
 193 }
 194
 195 static const struct scmi_reset_ops reset_ops = {
 196         .num_domains_get = scmi_reset_num_domains_get,
 197         .name_get = scmi_reset_name_get,
 198         .latency_get = scmi_reset_latency_get,
 199         .reset = scmi_reset_domain_reset,
 200         .assert = scmi_reset_domain_assert,
 201         .deassert = scmi_reset_domain_deassert,
 202 };
 203
 204 static int scmi_reset_notify(const struct scmi_handle *handle, u32 domain_id,
 205                              bool enable)
 206 {
 207         int ret;
 208         u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0;
 209         struct scmi_xfer *t;
 210         struct scmi_msg_reset_notify *cfg;
 211
 212         ret = scmi_xfer_get_init(handle, RESET_NOTIFY,
 213                                  SCMI_PROTOCOL_RESET, sizeof(*cfg), 0, &t);
 214         if (ret)
 215                 return ret;
 216
 217         cfg = t->tx.buf;
 218         cfg->id = cpu_to_le32(domain_id);
 219         cfg->event_control = cpu_to_le32(evt_cntl);
 220
 221         ret = scmi_do_xfer(handle, t);
 222
 223         scmi_xfer_put(handle, t);
 224         return ret;
 225 }
 226
 227 static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle,
 228                                          u8 evt_id, u32 src_id, bool enable)
 229 {
 230         int ret;
 231
 232         ret = scmi_reset_notify(handle, src_id, enable);
 233         if (ret)
 234                 pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
 235                          evt_id, src_id, ret);
 236
 237         return ret;
 238 }
 239
 240 static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle,
 241                                            u8 evt_id, ktime_t timestamp,
 242                                            const void *payld, size_t payld_sz,
 243                                            void *report, u32 *src_id)
 244 {
 245         const struct scmi_reset_issued_notify_payld *p = payld;
 246         struct scmi_reset_issued_report *r = report;
 247
 248         if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz)
 249                 return NULL;
 250
 251         r->timestamp = timestamp;
 252         r->agent_id = le32_to_cpu(p->agent_id);
 253         r->domain_id = le32_to_cpu(p->domain_id);
 254         r->reset_state = le32_to_cpu(p->reset_state);
 255         *src_id = r->domain_id;
 256
 257         return r;
 258 }
 259
 260 static const struct scmi_event reset_events[] = {
 261         {
 262                 .id = SCMI_EVENT_RESET_ISSUED,
 263                 .max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld),
 264                 .max_report_sz = sizeof(struct scmi_reset_issued_report),
 265         },
 266 };
 267
 268 static const struct scmi_event_ops reset_event_ops = {
 269         .set_notify_enabled = scmi_reset_set_notify_enabled,
 270         .fill_custom_report = scmi_reset_fill_custom_report,
 271 };
 272
 273 static int scmi_reset_protocol_init(struct scmi_handle *handle)
 274 {
 275         int domain;
 276         u32 version;
 277         struct scmi_reset_info *pinfo;
 278
 279         scmi_version_get(handle, SCMI_PROTOCOL_RESET, &version);
 280
 281         dev_dbg(handle->dev, "Reset Version %d.%d\n",
 282                 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
 283
 284         pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
 285         if (!pinfo)
 286                 return -ENOMEM;
 287
 288         scmi_reset_attributes_get(handle, pinfo);
 289
 290         pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
 291                                        sizeof(*pinfo->dom_info), GFP_KERNEL);
 292         if (!pinfo->dom_info)
 293                 return -ENOMEM;
 294
 295         for (domain = 0; domain < pinfo->num_domains; domain++) {
 296                 struct reset_dom_info *dom = pinfo->dom_info + domain;
 297
 298                 scmi_reset_domain_attributes_get(handle, domain, dom);
 299         }
 300
 301         scmi_register_protocol_events(handle,
 302                                       SCMI_PROTOCOL_RESET, SCMI_PROTO_QUEUE_SZ,
 303                                       &reset_event_ops, reset_events,
 304                                       ARRAY_SIZE(reset_events),
 305                                       pinfo->num_domains);
 306
 307         pinfo->version = version;
 308         handle->reset_ops = &reset_ops;
 309         handle->reset_priv = pinfo;
 310
 311         return 0;
 312 }
 313
 314 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(SCMI_PROTOCOL_RESET, reset)