sys/dev/cpufreq/cpufreq_dt.c

   1 /*-
   2  * Copyright (c) 2018 Emmanuel Vadot <manu@FreeBSD.Org>
   3  * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  *
  27  * $FreeBSD$
  28  */
  29
  30 /*
  31  * Generic DT based cpufreq driver
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/bus.h>
  40 #include <sys/rman.h>
  41 #include <sys/kernel.h>
  42 #include <sys/module.h>
  43 #include <sys/cpu.h>
  44 #include <sys/cpuset.h>
  45 #include <sys/smp.h>
  46
  47 #include <dev/ofw/ofw_bus.h>
  48 #include <dev/ofw/ofw_bus_subr.h>
  49
  50 #include <dev/extres/clk/clk.h>
  51 #include <dev/extres/regulator/regulator.h>
  52
  53 #include "cpufreq_if.h"
  54
  55 #if 0
  56 #define DEBUG(dev, msg...) device_printf(dev, "cpufreq_dt: " msg);
  57 #else
  58 #define DEBUG(dev, msg...)
  59 #endif
  60
  61 enum opp_version {
  62         OPP_V1 = 1,
  63         OPP_V2,
  64 };
  65
  66 struct cpufreq_dt_opp {
  67         uint64_t        freq;
  68         uint32_t        uvolt_target;
  69         uint32_t        uvolt_min;
  70         uint32_t        uvolt_max;
  71         uint32_t        uamps;
  72         uint32_t        clk_latency;
  73         bool            turbo_mode;
  74         bool            opp_suspend;
  75 };
  76
  77 struct cpufreq_dt_softc {
  78         device_t dev;
  79         clk_t clk;
  80         regulator_t reg;
  81
  82         struct cpufreq_dt_opp *opp;
  83         ssize_t nopp;
  84
  85         cpuset_t cpus;
  86 };
  87
  88 static void
  89 cpufreq_dt_notify(device_t dev, uint64_t freq)
  90 {
  91         struct cpufreq_dt_softc *sc;
  92         struct pcpu *pc;
  93         int cpu;
  94
  95         sc = device_get_softc(dev);
  96
  97         CPU_FOREACH(cpu) {
  98                 if (CPU_ISSET(cpu, &sc->cpus)) {
  99                         pc = pcpu_find(cpu);
 100                         pc->pc_clock = freq;
 101                 }
 102         }
 103 }
 104
 105 static const struct cpufreq_dt_opp *
 106 cpufreq_dt_find_opp(device_t dev, uint64_t freq)
 107 {
 108         struct cpufreq_dt_softc *sc;
 109         ssize_t n;
 110
 111         sc = device_get_softc(dev);
 112
 113         DEBUG(dev, "Looking for freq %ju\n", freq);
 114         for (n = 0; n < sc->nopp; n++)
 115                 if (CPUFREQ_CMP(sc->opp[n].freq, freq))
 116                         return (&sc->opp[n]);
 117
 118         DEBUG(dev, "Couldn't find one\n");
 119         return (NULL);
 120 }
 121
 122 static void
 123 cpufreq_dt_opp_to_setting(device_t dev, const struct cpufreq_dt_opp *opp,
 124     struct cf_setting *set)
 125 {
 126         struct cpufreq_dt_softc *sc;
 127
 128         sc = device_get_softc(dev);
 129
 130         memset(set, 0, sizeof(*set));
 131         set->freq = opp->freq / 1000000;
 132         set->volts = opp->uvolt_target / 1000;
 133         set->power = CPUFREQ_VAL_UNKNOWN;
 134         set->lat = opp->clk_latency;
 135         set->dev = dev;
 136 }
 137
 138 static int
 139 cpufreq_dt_get(device_t dev, struct cf_setting *set)
 140 {
 141         struct cpufreq_dt_softc *sc;
 142         const struct cpufreq_dt_opp *opp;
 143         uint64_t freq;
 144
 145         sc = device_get_softc(dev);
 146
 147         DEBUG(dev, "cpufreq_dt_get\n");
 148         if (clk_get_freq(sc->clk, &freq) != 0)
 149                 return (ENXIO);
 150
 151         opp = cpufreq_dt_find_opp(dev, freq);
 152         if (opp == NULL) {
 153                 device_printf(dev, "Can't find the current freq in opp\n");
 154                 return (ENOENT);
 155         }
 156
 157         cpufreq_dt_opp_to_setting(dev, opp, set);
 158
 159         DEBUG(dev, "Current freq %dMhz\n", set->freq);
 160         return (0);
 161 }
 162
 163 static int
 164 cpufreq_dt_set(device_t dev, const struct cf_setting *set)
 165 {
 166         struct cpufreq_dt_softc *sc;
 167         const struct cpufreq_dt_opp *opp, *copp;
 168         uint64_t freq;
 169         int uvolt, error;
 170
 171         sc = device_get_softc(dev);
 172
 173         if (clk_get_freq(sc->clk, &freq) != 0) {
 174                 device_printf(dev, "Can't get current clk freq\n");
 175                 return (ENXIO);
 176         }
 177         /* Try to get current valtage by using regulator first. */
 178         error = regulator_get_voltage(sc->reg, &uvolt);
 179         if (error != 0) {
 180                 /*
 181                  * Try oppoints table as backup way. However,
 182                  * this is insufficient because the actual processor
 183                  * frequency may not be in the table. PLL frequency
 184                  * granularity can be different that granularity of
 185                  * oppoint table.
 186                  */
 187                 copp = cpufreq_dt_find_opp(sc->dev, freq);
 188                 if (copp == NULL) {
 189                         device_printf(dev,
 190                             "Can't find the current freq in opp\n");
 191                         return (ENOENT);
 192                 }
 193                 uvolt = copp->uvolt_target;
 194
 195         }
 196
 197         opp = cpufreq_dt_find_opp(sc->dev, set->freq * 1000000);
 198         if (opp == NULL) {
 199                 device_printf(dev, "Couldn't find an opp for this freq\n");
 200                 return (EINVAL);
 201         }
 202         DEBUG(sc->dev, "Current freq %ju, uvolt: %d\n", freq, uvolt);
 203         DEBUG(sc->dev, "Target freq %ju, , uvolt: %d\n",
 204             opp->freq, opp->uvolt_target);
 205
 206         if (uvolt < opp->uvolt_target) {
 207                 DEBUG(dev, "Changing regulator from %u to %u\n",
 208                     uvolt, opp->uvolt_target);
 209                 error = regulator_set_voltage(sc->reg,
 210                     opp->uvolt_min,
 211                     opp->uvolt_max);
 212                 if (error != 0) {
 213                         DEBUG(dev, "Failed, backout\n");
 214                         return (ENXIO);
 215                 }
 216         }
 217
 218         DEBUG(dev, "Setting clk to %ju\n", opp->freq);
 219         error = clk_set_freq(sc->clk, opp->freq, CLK_SET_ROUND_DOWN);
 220         if (error != 0) {
 221                 DEBUG(dev, "Failed, backout\n");
 222                 /* Restore previous voltage (best effort) */
 223                 error = regulator_set_voltage(sc->reg,
 224                     copp->uvolt_min,
 225                     copp->uvolt_max);
 226                 return (ENXIO);
 227         }
 228
 229         if (uvolt > opp->uvolt_target) {
 230                 DEBUG(dev, "Changing regulator from %u to %u\n",
 231                     uvolt, opp->uvolt_target);
 232                 error = regulator_set_voltage(sc->reg,
 233                     opp->uvolt_min,
 234                     opp->uvolt_max);
 235                 if (error != 0) {
 236                         DEBUG(dev, "Failed to switch regulator to %d\n",
 237                             opp->uvolt_target);
 238                         /* Restore previous CPU frequency (best effort) */
 239                         (void)clk_set_freq(sc->clk, copp->freq, 0);
 240                         return (ENXIO);
 241                 }
 242         }
 243
 244         if (clk_get_freq(sc->clk, &freq) == 0)
 245                 cpufreq_dt_notify(dev, freq);
 246
 247         return (0);
 248 }
 249
 250
 251 static int
 252 cpufreq_dt_type(device_t dev, int *type)
 253 {
 254         if (type == NULL)
 255                 return (EINVAL);
 256
 257         *type = CPUFREQ_TYPE_ABSOLUTE;
 258         return (0);
 259 }
 260
 261 static int
 262 cpufreq_dt_settings(device_t dev, struct cf_setting *sets, int *count)
 263 {
 264         struct cpufreq_dt_softc *sc;
 265         ssize_t n;
 266
 267         DEBUG(dev, "cpufreq_dt_settings\n");
 268         if (sets == NULL || count == NULL)
 269                 return (EINVAL);
 270
 271         sc = device_get_softc(dev);
 272
 273         if (*count < sc->nopp) {
 274                 *count = (int)sc->nopp;
 275                 return (E2BIG);
 276         }
 277
 278         for (n = 0; n < sc->nopp; n++)
 279                 cpufreq_dt_opp_to_setting(dev, &sc->opp[n], &sets[n]);
 280
 281         *count = (int)sc->nopp;
 282
 283         return (0);
 284 }
 285
 286 static void
 287 cpufreq_dt_identify(driver_t *driver, device_t parent)
 288 {
 289         phandle_t node;
 290
 291         /* Properties must be listed under node /cpus/cpu@0 */
 292         node = ofw_bus_get_node(parent);
 293
 294         /* The cpu@0 node must have the following properties */
 295         if (!OF_hasprop(node, "clocks") ||
 296             (!OF_hasprop(node, "cpu-supply") &&
 297             !OF_hasprop(node, "cpu0-supply")))
 298                 return;
 299
 300         if (!OF_hasprop(node, "operating-points") &&
 301             !OF_hasprop(node, "operating-points-v2"))
 302                 return;
 303
 304         if (device_find_child(parent, "cpufreq_dt", -1) != NULL)
 305                 return;
 306
 307         if (BUS_ADD_CHILD(parent, 0, "cpufreq_dt", -1) == NULL)
 308                 device_printf(parent, "add cpufreq_dt child failed\n");
 309 }
 310
 311 static int
 312 cpufreq_dt_probe(device_t dev)
 313 {
 314         phandle_t node;
 315
 316         node = ofw_bus_get_node(device_get_parent(dev));
 317
 318         if (!OF_hasprop(node, "clocks") ||
 319             (!OF_hasprop(node, "cpu-supply") &&
 320             !OF_hasprop(node, "cpu0-supply")))
 321
 322                 return (ENXIO);
 323
 324         if (!OF_hasprop(node, "operating-points") &&
 325           !OF_hasprop(node, "operating-points-v2"))
 326                 return (ENXIO);
 327
 328         device_set_desc(dev, "Generic cpufreq driver");
 329         return (BUS_PROBE_GENERIC);
 330 }
 331
 332 static int
 333 cpufreq_dt_oppv1_parse(struct cpufreq_dt_softc *sc, phandle_t node)
 334 {
 335         uint32_t *opp, lat;
 336         ssize_t n;
 337
 338         sc->nopp = OF_getencprop_alloc_multi(node, "operating-points",
 339             sizeof(uint32_t) * 2, (void **)&opp);
 340         if (sc->nopp == -1)
 341                 return (ENXIO);
 342
 343         if (OF_getencprop(node, "clock-latency", &lat, sizeof(lat)) == -1)
 344                 lat = CPUFREQ_VAL_UNKNOWN;
 345
 346         sc->opp = malloc(sizeof(*sc->opp) * sc->nopp, M_DEVBUF, M_WAITOK);
 347
 348         for (n = 0; n < sc->nopp; n++) {
 349                 sc->opp[n].freq = opp[n * 2 + 0] * 1000;
 350                 sc->opp[n].uvolt_min = opp[n * 2 + 1];
 351                 sc->opp[n].uvolt_max = sc->opp[n].uvolt_min;
 352                 sc->opp[n].uvolt_target = sc->opp[n].uvolt_min;
 353                 sc->opp[n].clk_latency = lat;
 354
 355                 if (bootverbose)
 356                         device_printf(sc->dev, "%ju.%03ju MHz, %u uV\n",
 357                             sc->opp[n].freq / 1000000,
 358                             sc->opp[n].freq % 1000000,
 359                             sc->opp[n].uvolt_target);
 360         }
 361         free(opp, M_OFWPROP);
 362
 363         return (0);
 364 }
 365
 366 static int
 367 cpufreq_dt_oppv2_parse(struct cpufreq_dt_softc *sc, phandle_t node)
 368 {
 369         phandle_t opp, opp_table, opp_xref;
 370         pcell_t cell[2];
 371         uint32_t *volts, lat;
 372         int nvolt, i;
 373
 374         if (OF_getencprop(node, "operating-points-v2", &opp_xref,
 375             sizeof(opp_xref)) == -1) {
 376                 device_printf(sc->dev, "Cannot get xref to oppv2 table\n");
 377                 return (ENXIO);
 378         }
 379
 380         opp_table = OF_node_from_xref(opp_xref);
 381         if (opp_table == opp_xref)
 382                 return (ENXIO);
 383
 384         if (!OF_hasprop(opp_table, "opp-shared")) {
 385                 device_printf(sc->dev, "Only opp-shared is supported\n");
 386                 return (ENXIO);
 387         }
 388
 389         for (opp = OF_child(opp_table); opp > 0; opp = OF_peer(opp))
 390                 sc->nopp += 1;
 391
 392         sc->opp = malloc(sizeof(*sc->opp) * sc->nopp, M_DEVBUF, M_WAITOK);
 393
 394         for (i = 0, opp_table = OF_child(opp_table); opp_table > 0;
 395              opp_table = OF_peer(opp_table), i++) {
 396                 /* opp-hz is a required property */
 397                 if (OF_getencprop(opp_table, "opp-hz", cell,
 398                     sizeof(cell)) == -1)
 399                         continue;
 400
 401                 sc->opp[i].freq = cell[0];
 402                 sc->opp[i].freq <<= 32;
 403                 sc->opp[i].freq |= cell[1];
 404
 405                 if (OF_getencprop(opp_table, "clock-latency", &lat,
 406                     sizeof(lat)) == -1)
 407                         sc->opp[i].clk_latency = CPUFREQ_VAL_UNKNOWN;
 408                 else
 409                         sc->opp[i].clk_latency = (int)lat;
 410
 411                 if (OF_hasprop(opp_table, "turbo-mode"))
 412                         sc->opp[i].turbo_mode = true;
 413                 if (OF_hasprop(opp_table, "opp-suspend"))
 414                         sc->opp[i].opp_suspend = true;
 415
 416                 nvolt = OF_getencprop_alloc_multi(opp_table, "opp-microvolt",
 417                   sizeof(*volts), (void **)&volts);
 418                 if (nvolt == 1) {
 419                         sc->opp[i].uvolt_target = volts[0];
 420                         sc->opp[i].uvolt_min = volts[0];
 421                         sc->opp[i].uvolt_max = volts[0];
 422                 } else if (nvolt == 3) {
 423                         sc->opp[i].uvolt_target = volts[0];
 424                         sc->opp[i].uvolt_min = volts[1];
 425                         sc->opp[i].uvolt_max = volts[2];
 426                 } else {
 427                         device_printf(sc->dev,
 428                             "Wrong count of opp-microvolt property\n");
 429                         OF_prop_free(volts);
 430                         free(sc->opp, M_DEVBUF);
 431                         return (ENXIO);
 432                 }
 433                 OF_prop_free(volts);
 434
 435                 if (bootverbose)
 436                         device_printf(sc->dev, "%ju.%03ju Mhz (%u uV)\n",
 437                             sc->opp[i].freq / 1000000,
 438                             sc->opp[i].freq % 1000000,
 439                             sc->opp[i].uvolt_target);
 440         }
 441         return (0);
 442 }
 443
 444 static int
 445 cpufreq_dt_attach(device_t dev)
 446 {
 447         struct cpufreq_dt_softc *sc;
 448         phandle_t node;
 449         phandle_t cnode, opp, copp;
 450         int cpu;
 451         uint64_t freq;
 452         int rv = 0;
 453         enum opp_version version;
 454
 455         sc = device_get_softc(dev);
 456         sc->dev = dev;
 457         node = ofw_bus_get_node(device_get_parent(dev));
 458
 459         if (regulator_get_by_ofw_property(dev, node,
 460             "cpu-supply", &sc->reg) != 0) {
 461                 if (regulator_get_by_ofw_property(dev, node,
 462                     "cpu0-supply", &sc->reg) != 0) {
 463                         device_printf(dev, "no regulator for %s\n",
 464                             ofw_bus_get_name(device_get_parent(dev)));
 465                         return (ENXIO);
 466                 }
 467         }
 468
 469         if (clk_get_by_ofw_index(dev, node, 0, &sc->clk) != 0) {
 470                 device_printf(dev, "no clock for %s\n",
 471                     ofw_bus_get_name(device_get_parent(dev)));
 472                 regulator_release(sc->reg);
 473                 return (ENXIO);
 474         }
 475
 476         if (OF_hasprop(node, "operating-points")) {
 477                 version = OPP_V1;
 478                 rv = cpufreq_dt_oppv1_parse(sc, node);
 479                 if (rv != 0) {
 480                         device_printf(dev, "Failed to parse opp-v1 table\n");
 481                         return (rv);
 482                 }
 483                 OF_getencprop(node, "operating-points", &opp,
 484                     sizeof(opp));
 485         } else {
 486                 version = OPP_V2;
 487                 rv = cpufreq_dt_oppv2_parse(sc, node);
 488                 if (rv != 0) {
 489                         device_printf(dev, "Failed to parse opp-v2 table\n");
 490                         return (rv);
 491                 }
 492                 OF_getencprop(node, "operating-points-v2", &opp,
 493                     sizeof(opp));
 494         }
 495
 496         /*
 497          * Find all CPUs that share the same opp table
 498          */
 499         CPU_ZERO(&sc->cpus);
 500         cpu = device_get_unit(device_get_parent(dev));
 501         for (cnode = node; cnode > 0; cnode = OF_peer(cnode), cpu++) {
 502                 copp = -1;
 503                 if (version == OPP_V1)
 504                         OF_getencprop(cnode, "operating-points", &copp,
 505                             sizeof(copp));
 506                 else if (version == OPP_V2)
 507                         OF_getencprop(cnode, "operating-points-v2",
 508                             &copp, sizeof(copp));
 509                 if (opp == copp)
 510                         CPU_SET(cpu, &sc->cpus);
 511         }
 512
 513         if (clk_get_freq(sc->clk, &freq) == 0)
 514                 cpufreq_dt_notify(dev, freq);
 515
 516         cpufreq_register(dev);
 517
 518         return (0);
 519 }
 520
 521
 522 static device_method_t cpufreq_dt_methods[] = {
 523         /* Device interface */
 524         DEVMETHOD(device_identify,      cpufreq_dt_identify),
 525         DEVMETHOD(device_probe,         cpufreq_dt_probe),
 526         DEVMETHOD(device_attach,        cpufreq_dt_attach),
 527
 528         /* cpufreq interface */
 529         DEVMETHOD(cpufreq_drv_get,      cpufreq_dt_get),
 530         DEVMETHOD(cpufreq_drv_set,      cpufreq_dt_set),
 531         DEVMETHOD(cpufreq_drv_type,     cpufreq_dt_type),
 532         DEVMETHOD(cpufreq_drv_settings, cpufreq_dt_settings),
 533
 534         DEVMETHOD_END
 535 };
 536
 537 static driver_t cpufreq_dt_driver = {
 538         "cpufreq_dt",
 539         cpufreq_dt_methods,
 540         sizeof(struct cpufreq_dt_softc),
 541 };
 542
 543 static devclass_t cpufreq_dt_devclass;
 544
 545 DRIVER_MODULE(cpufreq_dt, cpu, cpufreq_dt_driver, cpufreq_dt_devclass, 0, 0);
 546 MODULE_VERSION(cpufreq_dt, 1);