drivers/firmware/arm_scmi/perf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * System Control and Management Interface (SCMI) Performance Protocol
   4  *
   5  * Copyright (C) 2018 ARM Ltd.
   6  */
   7
   8 #include <linux/of.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/pm_opp.h>
  11 #include <linux/sort.h>
  12
  13 #include "common.h"
  14
  15 enum scmi_performance_protocol_cmd {
  16         PERF_DOMAIN_ATTRIBUTES = 0x3,
  17         PERF_DESCRIBE_LEVELS = 0x4,
  18         PERF_LIMITS_SET = 0x5,
  19         PERF_LIMITS_GET = 0x6,
  20         PERF_LEVEL_SET = 0x7,
  21         PERF_LEVEL_GET = 0x8,
  22         PERF_NOTIFY_LIMITS = 0x9,
  23         PERF_NOTIFY_LEVEL = 0xa,
  24 };
  25
  26 struct scmi_opp {
  27         u32 perf;
  28         u32 power;
  29         u32 trans_latency_us;
  30 };
  31
  32 struct scmi_msg_resp_perf_attributes {
  33         __le16 num_domains;
  34         __le16 flags;
  35 #define POWER_SCALE_IN_MILLIWATT(x)     ((x) & BIT(0))
  36         __le32 stats_addr_low;
  37         __le32 stats_addr_high;
  38         __le32 stats_size;
  39 };
  40
  41 struct scmi_msg_resp_perf_domain_attributes {
  42         __le32 flags;
  43 #define SUPPORTS_SET_LIMITS(x)          ((x) & BIT(31))
  44 #define SUPPORTS_SET_PERF_LVL(x)        ((x) & BIT(30))
  45 #define SUPPORTS_PERF_LIMIT_NOTIFY(x)   ((x) & BIT(29))
  46 #define SUPPORTS_PERF_LEVEL_NOTIFY(x)   ((x) & BIT(28))
  47         __le32 rate_limit_us;
  48         __le32 sustained_freq_khz;
  49         __le32 sustained_perf_level;
  50             u8 name[SCMI_MAX_STR_SIZE];
  51 };
  52
  53 struct scmi_msg_perf_describe_levels {
  54         __le32 domain;
  55         __le32 level_index;
  56 };
  57
  58 struct scmi_perf_set_limits {
  59         __le32 domain;
  60         __le32 max_level;
  61         __le32 min_level;
  62 };
  63
  64 struct scmi_perf_get_limits {
  65         __le32 max_level;
  66         __le32 min_level;
  67 };
  68
  69 struct scmi_perf_set_level {
  70         __le32 domain;
  71         __le32 level;
  72 };
  73
  74 struct scmi_perf_notify_level_or_limits {
  75         __le32 domain;
  76         __le32 notify_enable;
  77 };
  78
  79 struct scmi_msg_resp_perf_describe_levels {
  80         __le16 num_returned;
  81         __le16 num_remaining;
  82         struct {
  83                 __le32 perf_val;
  84                 __le32 power;
  85                 __le16 transition_latency_us;
  86                 __le16 reserved;
  87         } opp[0];
  88 };
  89
  90 struct perf_dom_info {
  91         bool set_limits;
  92         bool set_perf;
  93         bool perf_limit_notify;
  94         bool perf_level_notify;
  95         u32 opp_count;
  96         u32 sustained_freq_khz;
  97         u32 sustained_perf_level;
  98         u32 mult_factor;
  99         char name[SCMI_MAX_STR_SIZE];
 100         struct scmi_opp opp[MAX_OPPS];
 101 };
 102
 103 struct scmi_perf_info {
 104         int num_domains;
 105         bool power_scale_mw;
 106         u64 stats_addr;
 107         u32 stats_size;
 108         struct perf_dom_info *dom_info;
 109 };
 110
 111 static int scmi_perf_attributes_get(const struct scmi_handle *handle,
 112                                     struct scmi_perf_info *pi)
 113 {
 114         int ret;
 115         struct scmi_xfer *t;
 116         struct scmi_msg_resp_perf_attributes *attr;
 117
 118         ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
 119                                  SCMI_PROTOCOL_PERF, 0, sizeof(*attr), &t);
 120         if (ret)
 121                 return ret;
 122
 123         attr = t->rx.buf;
 124
 125         ret = scmi_do_xfer(handle, t);
 126         if (!ret) {
 127                 u16 flags = le16_to_cpu(attr->flags);
 128
 129                 pi->num_domains = le16_to_cpu(attr->num_domains);
 130                 pi->power_scale_mw = POWER_SCALE_IN_MILLIWATT(flags);
 131                 pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
 132                                 (u64)le32_to_cpu(attr->stats_addr_high) << 32;
 133                 pi->stats_size = le32_to_cpu(attr->stats_size);
 134         }
 135
 136         scmi_xfer_put(handle, t);
 137         return ret;
 138 }
 139
 140 static int
 141 scmi_perf_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
 142                                 struct perf_dom_info *dom_info)
 143 {
 144         int ret;
 145         struct scmi_xfer *t;
 146         struct scmi_msg_resp_perf_domain_attributes *attr;
 147
 148         ret = scmi_xfer_get_init(handle, PERF_DOMAIN_ATTRIBUTES,
 149                                  SCMI_PROTOCOL_PERF, sizeof(domain),
 150                                  sizeof(*attr), &t);
 151         if (ret)
 152                 return ret;
 153
 154         *(__le32 *)t->tx.buf = cpu_to_le32(domain);
 155         attr = t->rx.buf;
 156
 157         ret = scmi_do_xfer(handle, t);
 158         if (!ret) {
 159                 u32 flags = le32_to_cpu(attr->flags);
 160
 161                 dom_info->set_limits = SUPPORTS_SET_LIMITS(flags);
 162                 dom_info->set_perf = SUPPORTS_SET_PERF_LVL(flags);
 163                 dom_info->perf_limit_notify = SUPPORTS_PERF_LIMIT_NOTIFY(flags);
 164                 dom_info->perf_level_notify = SUPPORTS_PERF_LEVEL_NOTIFY(flags);
 165                 dom_info->sustained_freq_khz =
 166                                         le32_to_cpu(attr->sustained_freq_khz);
 167                 dom_info->sustained_perf_level =
 168                                         le32_to_cpu(attr->sustained_perf_level);
 169                 dom_info->mult_factor = (dom_info->sustained_freq_khz * 1000) /
 170                                         dom_info->sustained_perf_level;
 171                 memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 172         }
 173
 174         scmi_xfer_put(handle, t);
 175         return ret;
 176 }
 177
 178 static int opp_cmp_func(const void *opp1, const void *opp2)
 179 {
 180         const struct scmi_opp *t1 = opp1, *t2 = opp2;
 181
 182         return t1->perf - t2->perf;
 183 }
 184
 185 static int
 186 scmi_perf_describe_levels_get(const struct scmi_handle *handle, u32 domain,
 187                               struct perf_dom_info *perf_dom)
 188 {
 189         int ret, cnt;
 190         u32 tot_opp_cnt = 0;
 191         u16 num_returned, num_remaining;
 192         struct scmi_xfer *t;
 193         struct scmi_opp *opp;
 194         struct scmi_msg_perf_describe_levels *dom_info;
 195         struct scmi_msg_resp_perf_describe_levels *level_info;
 196
 197         ret = scmi_xfer_get_init(handle, PERF_DESCRIBE_LEVELS,
 198                                  SCMI_PROTOCOL_PERF, sizeof(*dom_info), 0, &t);
 199         if (ret)
 200                 return ret;
 201
 202         dom_info = t->tx.buf;
 203         level_info = t->rx.buf;
 204
 205         do {
 206                 dom_info->domain = cpu_to_le32(domain);
 207                 /* Set the number of OPPs to be skipped/already read */
 208                 dom_info->level_index = cpu_to_le32(tot_opp_cnt);
 209
 210                 ret = scmi_do_xfer(handle, t);
 211                 if (ret)
 212                         break;
 213
 214                 num_returned = le16_to_cpu(level_info->num_returned);
 215                 num_remaining = le16_to_cpu(level_info->num_remaining);
 216                 if (tot_opp_cnt + num_returned > MAX_OPPS) {
 217                         dev_err(handle->dev, "No. of OPPs exceeded MAX_OPPS");
 218                         break;
 219                 }
 220
 221                 opp = &perf_dom->opp[tot_opp_cnt];
 222                 for (cnt = 0; cnt < num_returned; cnt++, opp++) {
 223                         opp->perf = le32_to_cpu(level_info->opp[cnt].perf_val);
 224                         opp->power = le32_to_cpu(level_info->opp[cnt].power);
 225                         opp->trans_latency_us = le16_to_cpu
 226                                 (level_info->opp[cnt].transition_latency_us);
 227
 228                         dev_dbg(handle->dev, "Level %d Power %d Latency %dus\n",
 229                                 opp->perf, opp->power, opp->trans_latency_us);
 230                 }
 231
 232                 tot_opp_cnt += num_returned;
 233                 /*
 234                  * check for both returned and remaining to avoid infinite
 235                  * loop due to buggy firmware
 236                  */
 237         } while (num_returned && num_remaining);
 238
 239         perf_dom->opp_count = tot_opp_cnt;
 240         scmi_xfer_put(handle, t);
 241
 242         sort(perf_dom->opp, tot_opp_cnt, sizeof(*opp), opp_cmp_func, NULL);
 243         return ret;
 244 }
 245
 246 static int scmi_perf_limits_set(const struct scmi_handle *handle, u32 domain,
 247                                 u32 max_perf, u32 min_perf)
 248 {
 249         int ret;
 250         struct scmi_xfer *t;
 251         struct scmi_perf_set_limits *limits;
 252
 253         ret = scmi_xfer_get_init(handle, PERF_LIMITS_SET, SCMI_PROTOCOL_PERF,
 254                                  sizeof(*limits), 0, &t);
 255         if (ret)
 256                 return ret;
 257
 258         limits = t->tx.buf;
 259         limits->domain = cpu_to_le32(domain);
 260         limits->max_level = cpu_to_le32(max_perf);
 261         limits->min_level = cpu_to_le32(min_perf);
 262
 263         ret = scmi_do_xfer(handle, t);
 264
 265         scmi_xfer_put(handle, t);
 266         return ret;
 267 }
 268
 269 static int scmi_perf_limits_get(const struct scmi_handle *handle, u32 domain,
 270                                 u32 *max_perf, u32 *min_perf)
 271 {
 272         int ret;
 273         struct scmi_xfer *t;
 274         struct scmi_perf_get_limits *limits;
 275
 276         ret = scmi_xfer_get_init(handle, PERF_LIMITS_GET, SCMI_PROTOCOL_PERF,
 277                                  sizeof(__le32), 0, &t);
 278         if (ret)
 279                 return ret;
 280
 281         *(__le32 *)t->tx.buf = cpu_to_le32(domain);
 282
 283         ret = scmi_do_xfer(handle, t);
 284         if (!ret) {
 285                 limits = t->rx.buf;
 286
 287                 *max_perf = le32_to_cpu(limits->max_level);
 288                 *min_perf = le32_to_cpu(limits->min_level);
 289         }
 290
 291         scmi_xfer_put(handle, t);
 292         return ret;
 293 }
 294
 295 static int scmi_perf_level_set(const struct scmi_handle *handle, u32 domain,
 296                                u32 level, bool poll)
 297 {
 298         int ret;
 299         struct scmi_xfer *t;
 300         struct scmi_perf_set_level *lvl;
 301
 302         ret = scmi_xfer_get_init(handle, PERF_LEVEL_SET, SCMI_PROTOCOL_PERF,
 303                                  sizeof(*lvl), 0, &t);
 304         if (ret)
 305                 return ret;
 306
 307         t->hdr.poll_completion = poll;
 308         lvl = t->tx.buf;
 309         lvl->domain = cpu_to_le32(domain);
 310         lvl->level = cpu_to_le32(level);
 311
 312         ret = scmi_do_xfer(handle, t);
 313
 314         scmi_xfer_put(handle, t);
 315         return ret;
 316 }
 317
 318 static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain,
 319                                u32 *level, bool poll)
 320 {
 321         int ret;
 322         struct scmi_xfer *t;
 323
 324         ret = scmi_xfer_get_init(handle, PERF_LEVEL_GET, SCMI_PROTOCOL_PERF,
 325                                  sizeof(u32), sizeof(u32), &t);
 326         if (ret)
 327                 return ret;
 328
 329         t->hdr.poll_completion = poll;
 330         *(__le32 *)t->tx.buf = cpu_to_le32(domain);
 331
 332         ret = scmi_do_xfer(handle, t);
 333         if (!ret)
 334                 *level = le32_to_cpu(*(__le32 *)t->rx.buf);
 335
 336         scmi_xfer_put(handle, t);
 337         return ret;
 338 }
 339
 340 /* Device specific ops */
 341 static int scmi_dev_domain_id(struct device *dev)
 342 {
 343         struct of_phandle_args clkspec;
 344
 345         if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
 346                                        0, &clkspec))
 347                 return -EINVAL;
 348
 349         return clkspec.args[0];
 350 }
 351
 352 static int scmi_dvfs_device_opps_add(const struct scmi_handle *handle,
 353                                      struct device *dev)
 354 {
 355         int idx, ret, domain;
 356         unsigned long freq;
 357         struct scmi_opp *opp;
 358         struct perf_dom_info *dom;
 359         struct scmi_perf_info *pi = handle->perf_priv;
 360
 361         domain = scmi_dev_domain_id(dev);
 362         if (domain < 0)
 363                 return domain;
 364
 365         dom = pi->dom_info + domain;
 366         if (!dom)
 367                 return -EIO;
 368
 369         for (opp = dom->opp, idx = 0; idx < dom->opp_count; idx++, opp++) {
 370                 freq = opp->perf * dom->mult_factor;
 371
 372                 ret = dev_pm_opp_add(dev, freq, 0);
 373                 if (ret) {
 374                         dev_warn(dev, "failed to add opp %luHz\n", freq);
 375
 376                         while (idx-- > 0) {
 377                                 freq = (--opp)->perf * dom->mult_factor;
 378                                 dev_pm_opp_remove(dev, freq);
 379                         }
 380                         return ret;
 381                 }
 382         }
 383         return 0;
 384 }
 385
 386 static int scmi_dvfs_transition_latency_get(const struct scmi_handle *handle,
 387                                             struct device *dev)
 388 {
 389         struct perf_dom_info *dom;
 390         struct scmi_perf_info *pi = handle->perf_priv;
 391         int domain = scmi_dev_domain_id(dev);
 392
 393         if (domain < 0)
 394                 return domain;
 395
 396         dom = pi->dom_info + domain;
 397         if (!dom)
 398                 return -EIO;
 399
 400         /* uS to nS */
 401         return dom->opp[dom->opp_count - 1].trans_latency_us * 1000;
 402 }
 403
 404 static int scmi_dvfs_freq_set(const struct scmi_handle *handle, u32 domain,
 405                               unsigned long freq, bool poll)
 406 {
 407         struct scmi_perf_info *pi = handle->perf_priv;
 408         struct perf_dom_info *dom = pi->dom_info + domain;
 409
 410         return scmi_perf_level_set(handle, domain, freq / dom->mult_factor,
 411                                    poll);
 412 }
 413
 414 static int scmi_dvfs_freq_get(const struct scmi_handle *handle, u32 domain,
 415                               unsigned long *freq, bool poll)
 416 {
 417         int ret;
 418         u32 level;
 419         struct scmi_perf_info *pi = handle->perf_priv;
 420         struct perf_dom_info *dom = pi->dom_info + domain;
 421
 422         ret = scmi_perf_level_get(handle, domain, &level, poll);
 423         if (!ret)
 424                 *freq = level * dom->mult_factor;
 425
 426         return ret;
 427 }
 428
 429 static struct scmi_perf_ops perf_ops = {
 430         .limits_set = scmi_perf_limits_set,
 431         .limits_get = scmi_perf_limits_get,
 432         .level_set = scmi_perf_level_set,
 433         .level_get = scmi_perf_level_get,
 434         .device_domain_id = scmi_dev_domain_id,
 435         .transition_latency_get = scmi_dvfs_transition_latency_get,
 436         .device_opps_add = scmi_dvfs_device_opps_add,
 437         .freq_set = scmi_dvfs_freq_set,
 438         .freq_get = scmi_dvfs_freq_get,
 439 };
 440
 441 static int scmi_perf_protocol_init(struct scmi_handle *handle)
 442 {
 443         int domain;
 444         u32 version;
 445         struct scmi_perf_info *pinfo;
 446
 447         scmi_version_get(handle, SCMI_PROTOCOL_PERF, &version);
 448
 449         dev_dbg(handle->dev, "Performance Version %d.%d\n",
 450                 PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
 451
 452         pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
 453         if (!pinfo)
 454                 return -ENOMEM;
 455
 456         scmi_perf_attributes_get(handle, pinfo);
 457
 458         pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
 459                                        sizeof(*pinfo->dom_info), GFP_KERNEL);
 460         if (!pinfo->dom_info)
 461                 return -ENOMEM;
 462
 463         for (domain = 0; domain < pinfo->num_domains; domain++) {
 464                 struct perf_dom_info *dom = pinfo->dom_info + domain;
 465
 466                 scmi_perf_domain_attributes_get(handle, domain, dom);
 467                 scmi_perf_describe_levels_get(handle, domain, dom);
 468         }
 469
 470         handle->perf_ops = &perf_ops;
 471         handle->perf_priv = pinfo;
 472
 473         return 0;
 474 }
 475
 476 static int __init scmi_perf_init(void)
 477 {
 478         return scmi_protocol_register(SCMI_PROTOCOL_PERF,
 479                                       &scmi_perf_protocol_init);
 480 }
 481 subsys_initcall(scmi_perf_init);