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_RESET_TYPE         BIT(31)
  40 #define COLD_RESET_STATE        BIT(0)
  41 #define ARCH_COLD_RESET         (ARCH_RESET_TYPE | COLD_RESET_STATE)
  42 };
  43
  44 struct scmi_msg_reset_notify {
  45         __le32 id;
  46         __le32 event_control;
  47 #define RESET_TP_NOTIFY_ALL     BIT(0)
  48 };
  49
  50 struct scmi_reset_issued_notify_payld {
  51         __le32 agent_id;
  52         __le32 domain_id;
  53         __le32 reset_state;
  54 };
  55
  56 struct reset_dom_info {
  57         bool async_reset;
  58         bool reset_notify;
  59         u32 latency_us;
  60         char name[SCMI_MAX_STR_SIZE];
  61 };
  62
  63 struct scmi_reset_info {
  64         u32 version;
  65         int num_domains;
  66         struct reset_dom_info *dom_info;
  67 };
  68
  69 static int scmi_reset_attributes_get(const struct scmi_handle *handle,
  70                                      struct scmi_reset_info *pi)
  71 {
  72         int ret;
  73         struct scmi_xfer *t;
  74         u32 attr;
  75
  76         ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
  77                                  SCMI_PROTOCOL_RESET, 0, sizeof(attr), &t);
  78         if (ret)
  79                 return ret;
  80
  81         ret = scmi_do_xfer(handle, t);
  82         if (!ret) {
  83                 attr = get_unaligned_le32(t->rx.buf);
  84                 pi->num_domains = attr & NUM_RESET_DOMAIN_MASK;
  85         }
  86
  87         scmi_xfer_put(handle, t);
  88         return ret;
  89 }
  90
  91 static int
  92 scmi_reset_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
  93                                  struct reset_dom_info *dom_info)
  94 {
  95         int ret;
  96         struct scmi_xfer *t;
  97         struct scmi_msg_resp_reset_domain_attributes *attr;
  98
  99         ret = scmi_xfer_get_init(handle, RESET_DOMAIN_ATTRIBUTES,
 100                                  SCMI_PROTOCOL_RESET, sizeof(domain),
 101                                  sizeof(*attr), &t);
 102         if (ret)
 103                 return ret;
 104
 105         put_unaligned_le32(domain, t->tx.buf);
 106         attr = t->rx.buf;
 107
 108         ret = scmi_do_xfer(handle, t);
 109         if (!ret) {
 110                 u32 attributes = le32_to_cpu(attr->attributes);
 111
 112                 dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
 113                 dom_info->reset_notify = SUPPORTS_NOTIFY_RESET(attributes);
 114                 dom_info->latency_us = le32_to_cpu(attr->latency);
 115                 if (dom_info->latency_us == U32_MAX)
 116                         dom_info->latency_us = 0;
 117                 strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 118         }
 119
 120         scmi_xfer_put(handle, t);
 121         return ret;
 122 }
 123
 124 static int scmi_reset_num_domains_get(const struct scmi_handle *handle)
 125 {
 126         struct scmi_reset_info *pi = handle->reset_priv;
 127
 128         return pi->num_domains;
 129 }
 130
 131 static char *scmi_reset_name_get(const struct scmi_handle *handle, u32 domain)
 132 {
 133         struct scmi_reset_info *pi = handle->reset_priv;
 134         struct reset_dom_info *dom = pi->dom_info + domain;
 135
 136         return dom->name;
 137 }
 138
 139 static int scmi_reset_latency_get(const struct scmi_handle *handle, u32 domain)
 140 {
 141         struct scmi_reset_info *pi = handle->reset_priv;
 142         struct reset_dom_info *dom = pi->dom_info + domain;
 143
 144         return dom->latency_us;
 145 }
 146
 147 static int scmi_domain_reset(const struct scmi_handle *handle, u32 domain,
 148                              u32 flags, u32 state)
 149 {
 150         int ret;
 151         struct scmi_xfer *t;
 152         struct scmi_msg_reset_domain_reset *dom;
 153         struct scmi_reset_info *pi = handle->reset_priv;
 154         struct reset_dom_info *rdom = pi->dom_info + domain;
 155
 156         if (rdom->async_reset)
 157                 flags |= ASYNCHRONOUS_RESET;
 158
 159         ret = scmi_xfer_get_init(handle, RESET, SCMI_PROTOCOL_RESET,
 160                                  sizeof(*dom), 0, &t);
 161         if (ret)
 162                 return ret;
 163
 164         dom = t->tx.buf;
 165         dom->domain_id = cpu_to_le32(domain);
 166         dom->flags = cpu_to_le32(flags);
 167         dom->reset_state = cpu_to_le32(state);
 168
 169         if (rdom->async_reset)
 170                 ret = scmi_do_xfer_with_response(handle, t);
 171         else
 172                 ret = scmi_do_xfer(handle, t);
 173
 174         scmi_xfer_put(handle, t);
 175         return ret;
 176 }
 177
 178 static int scmi_reset_domain_reset(const struct scmi_handle *handle, u32 domain)
 179 {
 180         return scmi_domain_reset(handle, domain, AUTONOMOUS_RESET,
 181                                  ARCH_COLD_RESET);
 182 }
 183
 184 static int
 185 scmi_reset_domain_assert(const struct scmi_handle *handle, u32 domain)
 186 {
 187         return scmi_domain_reset(handle, domain, EXPLICIT_RESET_ASSERT,
 188                                  ARCH_COLD_RESET);
 189 }
 190
 191 static int
 192 scmi_reset_domain_deassert(const struct scmi_handle *handle, u32 domain)
 193 {
 194         return scmi_domain_reset(handle, domain, 0, ARCH_COLD_RESET);
 195 }
 196
 197 static const struct scmi_reset_ops reset_ops = {
 198         .num_domains_get = scmi_reset_num_domains_get,
 199         .name_get = scmi_reset_name_get,
 200         .latency_get = scmi_reset_latency_get,
 201         .reset = scmi_reset_domain_reset,
 202         .assert = scmi_reset_domain_assert,
 203         .deassert = scmi_reset_domain_deassert,
 204 };
 205
 206 static int scmi_reset_notify(const struct scmi_handle *handle, u32 domain_id,
 207                              bool enable)
 208 {
 209         int ret;
 210         u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0;
 211         struct scmi_xfer *t;
 212         struct scmi_msg_reset_notify *cfg;
 213
 214         ret = scmi_xfer_get_init(handle, RESET_NOTIFY,
 215                                  SCMI_PROTOCOL_RESET, sizeof(*cfg), 0, &t);
 216         if (ret)
 217                 return ret;
 218
 219         cfg = t->tx.buf;
 220         cfg->id = cpu_to_le32(domain_id);
 221         cfg->event_control = cpu_to_le32(evt_cntl);
 222
 223         ret = scmi_do_xfer(handle, t);
 224
 225         scmi_xfer_put(handle, t);
 226         return ret;
 227 }
 228
 229 static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle,
 230                                          u8 evt_id, u32 src_id, bool enable)
 231 {
 232         int ret;
 233
 234         ret = scmi_reset_notify(handle, src_id, enable);
 235         if (ret)
 236                 pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
 237                          evt_id, src_id, ret);
 238
 239         return ret;
 240 }
 241
 242 static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle,
 243                                            u8 evt_id, ktime_t timestamp,
 244                                            const void *payld, size_t payld_sz,
 245                                            void *report, u32 *src_id)
 246 {
 247         const struct scmi_reset_issued_notify_payld *p = payld;
 248         struct scmi_reset_issued_report *r = report;
 249
 250         if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz)
 251                 return NULL;
 252
 253         r->timestamp = timestamp;
 254         r->agent_id = le32_to_cpu(p->agent_id);
 255         r->domain_id = le32_to_cpu(p->domain_id);
 256         r->reset_state = le32_to_cpu(p->reset_state);
 257         *src_id = r->domain_id;
 258
 259         return r;
 260 }
 261
 262 static const struct scmi_event reset_events[] = {
 263         {
 264                 .id = SCMI_EVENT_RESET_ISSUED,
 265                 .max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld),
 266                 .max_report_sz = sizeof(struct scmi_reset_issued_report),
 267         },
 268 };
 269
 270 static const struct scmi_event_ops reset_event_ops = {
 271         .set_notify_enabled = scmi_reset_set_notify_enabled,
 272         .fill_custom_report = scmi_reset_fill_custom_report,
 273 };
 274
 275 static int scmi_reset_protocol_init(struct scmi_handle *handle)
 276 {
 277         int domain;
 278         u32 version;
 279         struct scmi_reset_info *pinfo;
 280
 281         scmi_version_get(handle, SCMI_PROTOCOL_RESET, &version);
 282
 283         dev_dbg(handle->dev, "Reset Version %d.%d\n",
 284                 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
 285
 286         pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
 287         if (!pinfo)
 288                 return -ENOMEM;
 289
 290         scmi_reset_attributes_get(handle, pinfo);
 291
 292         pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
 293                                        sizeof(*pinfo->dom_info), GFP_KERNEL);
 294         if (!pinfo->dom_info)
 295                 return -ENOMEM;
 296
 297         for (domain = 0; domain < pinfo->num_domains; domain++) {
 298                 struct reset_dom_info *dom = pinfo->dom_info + domain;
 299
 300                 scmi_reset_domain_attributes_get(handle, domain, dom);
 301         }
 302
 303         scmi_register_protocol_events(handle,
 304                                       SCMI_PROTOCOL_RESET, SCMI_PROTO_QUEUE_SZ,
 305                                       &reset_event_ops, reset_events,
 306                                       ARRAY_SIZE(reset_events),
 307                                       pinfo->num_domains);
 308
 309         pinfo->version = version;
 310         handle->reset_ops = &reset_ops;
 311         handle->reset_priv = pinfo;
 312
 313         return 0;
 314 }
 315
 316 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(SCMI_PROTOCOL_RESET, reset)