drivers/macintosh/windfarm_pm112.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Windfarm PowerMac thermal control.
   4  * Control loops for machines with SMU and PPC970MP processors.
   5  *
   6  * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
   7  * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
   8  */
   9 #include <linux/types.h>
  10 #include <linux/errno.h>
  11 #include <linux/kernel.h>
  12 #include <linux/device.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/reboot.h>
  15 #include <asm/prom.h>
  16 #include <asm/smu.h>
  17
  18 #include "windfarm.h"
  19 #include "windfarm_pid.h"
  20
  21 #define VERSION "0.2"
  22
  23 #define DEBUG
  24 #undef LOTSA_DEBUG
  25
  26 #ifdef DEBUG
  27 #define DBG(args...)    printk(args)
  28 #else
  29 #define DBG(args...)    do { } while(0)
  30 #endif
  31
  32 #ifdef LOTSA_DEBUG
  33 #define DBG_LOTS(args...)       printk(args)
  34 #else
  35 #define DBG_LOTS(args...)       do { } while(0)
  36 #endif
  37
  38 /* define this to force CPU overtemp to 60 degree, useful for testing
  39  * the overtemp code
  40  */
  41 #undef HACKED_OVERTEMP
  42
  43 /* We currently only handle 2 chips, 4 cores... */
  44 #define NR_CHIPS        2
  45 #define NR_CORES        4
  46 #define NR_CPU_FANS     3 * NR_CHIPS
  47
  48 /* Controls and sensors */
  49 static struct wf_sensor *sens_cpu_temp[NR_CORES];
  50 static struct wf_sensor *sens_cpu_power[NR_CORES];
  51 static struct wf_sensor *hd_temp;
  52 static struct wf_sensor *slots_power;
  53 static struct wf_sensor *u4_temp;
  54
  55 static struct wf_control *cpu_fans[NR_CPU_FANS];
  56 static char *cpu_fan_names[NR_CPU_FANS] = {
  57         "cpu-rear-fan-0",
  58         "cpu-rear-fan-1",
  59         "cpu-front-fan-0",
  60         "cpu-front-fan-1",
  61         "cpu-pump-0",
  62         "cpu-pump-1",
  63 };
  64 static struct wf_control *cpufreq_clamp;
  65
  66 /* Second pump isn't required (and isn't actually present) */
  67 #define CPU_FANS_REQD           (NR_CPU_FANS - 2)
  68 #define FIRST_PUMP              4
  69 #define LAST_PUMP               5
  70
  71 /* We keep a temperature history for average calculation of 180s */
  72 #define CPU_TEMP_HIST_SIZE      180
  73
  74 /* Scale factor for fan speed, *100 */
  75 static int cpu_fan_scale[NR_CPU_FANS] = {
  76         100,
  77         100,
  78         97,             /* inlet fans run at 97% of exhaust fan */
  79         97,
  80         100,            /* updated later */
  81         100,            /* updated later */
  82 };
  83
  84 static struct wf_control *backside_fan;
  85 static struct wf_control *slots_fan;
  86 static struct wf_control *drive_bay_fan;
  87
  88 /* PID loop state */
  89 static struct wf_cpu_pid_state cpu_pid[NR_CORES];
  90 static u32 cpu_thist[CPU_TEMP_HIST_SIZE];
  91 static int cpu_thist_pt;
  92 static s64 cpu_thist_total;
  93 static s32 cpu_all_tmax = 100 << 16;
  94 static int cpu_last_target;
  95 static struct wf_pid_state backside_pid;
  96 static int backside_tick;
  97 static struct wf_pid_state slots_pid;
  98 static bool slots_started;
  99 static struct wf_pid_state drive_bay_pid;
 100 static int drive_bay_tick;
 101
 102 static int nr_cores;
 103 static int have_all_controls;
 104 static int have_all_sensors;
 105 static bool started;
 106
 107 static int failure_state;
 108 #define FAILURE_SENSOR          1
 109 #define FAILURE_FAN             2
 110 #define FAILURE_PERM            4
 111 #define FAILURE_LOW_OVERTEMP    8
 112 #define FAILURE_HIGH_OVERTEMP   16
 113
 114 /* Overtemp values */
 115 #define LOW_OVER_AVERAGE        0
 116 #define LOW_OVER_IMMEDIATE      (10 << 16)
 117 #define LOW_OVER_CLEAR          ((-10) << 16)
 118 #define HIGH_OVER_IMMEDIATE     (14 << 16)
 119 #define HIGH_OVER_AVERAGE       (10 << 16)
 120 #define HIGH_OVER_IMMEDIATE     (14 << 16)
 121
 122
 123 /* Implementation... */
 124 static int create_cpu_loop(int cpu)
 125 {
 126         int chip = cpu / 2;
 127         int core = cpu & 1;
 128         struct smu_sdbp_header *hdr;
 129         struct smu_sdbp_cpupiddata *piddata;
 130         struct wf_cpu_pid_param pid;
 131         struct wf_control *main_fan = cpu_fans[0];
 132         s32 tmax;
 133         int fmin;
 134
 135         /* Get FVT params to get Tmax; if not found, assume default */
 136         hdr = smu_sat_get_sdb_partition(chip, 0xC4 + core, NULL);
 137         if (hdr) {
 138                 struct smu_sdbp_fvt *fvt = (struct smu_sdbp_fvt *)&hdr[1];
 139                 tmax = fvt->maxtemp << 16;
 140         } else
 141                 tmax = 95 << 16;        /* default to 95 degrees C */
 142
 143         /* We keep a global tmax for overtemp calculations */
 144         if (tmax < cpu_all_tmax)
 145                 cpu_all_tmax = tmax;
 146
 147         kfree(hdr);
 148
 149         /* Get PID params from the appropriate SAT */
 150         hdr = smu_sat_get_sdb_partition(chip, 0xC8 + core, NULL);
 151         if (hdr == NULL) {
 152                 printk(KERN_WARNING"windfarm: can't get CPU PID fan config\n");
 153                 return -EINVAL;
 154         }
 155         piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
 156
 157         /*
 158          * Darwin has a minimum fan speed of 1000 rpm for the 4-way and
 159          * 515 for the 2-way.  That appears to be overkill, so for now,
 160          * impose a minimum of 750 or 515.
 161          */
 162         fmin = (nr_cores > 2) ? 750 : 515;
 163
 164         /* Initialize PID loop */
 165         pid.interval = 1;       /* seconds */
 166         pid.history_len = piddata->history_len;
 167         pid.gd = piddata->gd;
 168         pid.gp = piddata->gp;
 169         pid.gr = piddata->gr / piddata->history_len;
 170         pid.pmaxadj = (piddata->max_power << 16) - (piddata->power_adj << 8);
 171         pid.ttarget = tmax - (piddata->target_temp_delta << 16);
 172         pid.tmax = tmax;
 173         pid.min = main_fan->ops->get_min(main_fan);
 174         pid.max = main_fan->ops->get_max(main_fan);
 175         if (pid.min < fmin)
 176                 pid.min = fmin;
 177
 178         wf_cpu_pid_init(&cpu_pid[cpu], &pid);
 179
 180         kfree(hdr);
 181
 182         return 0;
 183 }
 184
 185 static void cpu_max_all_fans(void)
 186 {
 187         int i;
 188
 189         /* We max all CPU fans in case of a sensor error. We also do the
 190          * cpufreq clamping now, even if it's supposedly done later by the
 191          * generic code anyway, we do it earlier here to react faster
 192          */
 193         if (cpufreq_clamp)
 194                 wf_control_set_max(cpufreq_clamp);
 195         for (i = 0; i < NR_CPU_FANS; ++i)
 196                 if (cpu_fans[i])
 197                         wf_control_set_max(cpu_fans[i]);
 198 }
 199
 200 static int cpu_check_overtemp(s32 temp)
 201 {
 202         int new_state = 0;
 203         s32 t_avg, t_old;
 204
 205         /* First check for immediate overtemps */
 206         if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) {
 207                 new_state |= FAILURE_LOW_OVERTEMP;
 208                 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
 209                         printk(KERN_ERR "windfarm: Overtemp due to immediate CPU"
 210                                " temperature !\n");
 211         }
 212         if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) {
 213                 new_state |= FAILURE_HIGH_OVERTEMP;
 214                 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
 215                         printk(KERN_ERR "windfarm: Critical overtemp due to"
 216                                " immediate CPU temperature !\n");
 217         }
 218
 219         /* We calculate a history of max temperatures and use that for the
 220          * overtemp management
 221          */
 222         t_old = cpu_thist[cpu_thist_pt];
 223         cpu_thist[cpu_thist_pt] = temp;
 224         cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE;
 225         cpu_thist_total -= t_old;
 226         cpu_thist_total += temp;
 227         t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE;
 228
 229         DBG_LOTS("t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
 230                  FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp));
 231
 232         /* Now check for average overtemps */
 233         if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) {
 234                 new_state |= FAILURE_LOW_OVERTEMP;
 235                 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
 236                         printk(KERN_ERR "windfarm: Overtemp due to average CPU"
 237                                " temperature !\n");
 238         }
 239         if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) {
 240                 new_state |= FAILURE_HIGH_OVERTEMP;
 241                 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
 242                         printk(KERN_ERR "windfarm: Critical overtemp due to"
 243                                " average CPU temperature !\n");
 244         }
 245
 246         /* Now handle overtemp conditions. We don't currently use the windfarm
 247          * overtemp handling core as it's not fully suited to the needs of those
 248          * new machine. This will be fixed later.
 249          */
 250         if (new_state) {
 251                 /* High overtemp -> immediate shutdown */
 252                 if (new_state & FAILURE_HIGH_OVERTEMP)
 253                         machine_power_off();
 254                 if ((failure_state & new_state) != new_state)
 255                         cpu_max_all_fans();
 256                 failure_state |= new_state;
 257         } else if ((failure_state & FAILURE_LOW_OVERTEMP) &&
 258                    (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) {
 259                 printk(KERN_ERR "windfarm: Overtemp condition cleared !\n");
 260                 failure_state &= ~FAILURE_LOW_OVERTEMP;
 261         }
 262
 263         return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP);
 264 }
 265
 266 static void cpu_fans_tick(void)
 267 {
 268         int err, cpu;
 269         s32 greatest_delta = 0;
 270         s32 temp, power, t_max = 0;
 271         int i, t, target = 0;
 272         struct wf_sensor *sr;
 273         struct wf_control *ct;
 274         struct wf_cpu_pid_state *sp;
 275
 276         DBG_LOTS(KERN_DEBUG);
 277         for (cpu = 0; cpu < nr_cores; ++cpu) {
 278                 /* Get CPU core temperature */
 279                 sr = sens_cpu_temp[cpu];
 280                 err = sr->ops->get_value(sr, &temp);
 281                 if (err) {
 282                         DBG("\n");
 283                         printk(KERN_WARNING "windfarm: CPU %d temperature "
 284                                "sensor error %d\n", cpu, err);
 285                         failure_state |= FAILURE_SENSOR;
 286                         cpu_max_all_fans();
 287                         return;
 288                 }
 289
 290                 /* Keep track of highest temp */
 291                 t_max = max(t_max, temp);
 292
 293                 /* Get CPU power */
 294                 sr = sens_cpu_power[cpu];
 295                 err = sr->ops->get_value(sr, &power);
 296                 if (err) {
 297                         DBG("\n");
 298                         printk(KERN_WARNING "windfarm: CPU %d power "
 299                                "sensor error %d\n", cpu, err);
 300                         failure_state |= FAILURE_SENSOR;
 301                         cpu_max_all_fans();
 302                         return;
 303                 }
 304
 305                 /* Run PID */
 306                 sp = &cpu_pid[cpu];
 307                 t = wf_cpu_pid_run(sp, power, temp);
 308
 309                 if (cpu == 0 || sp->last_delta > greatest_delta) {
 310                         greatest_delta = sp->last_delta;
 311                         target = t;
 312                 }
 313                 DBG_LOTS("[%d] P=%d.%.3d T=%d.%.3d ",
 314                     cpu, FIX32TOPRINT(power), FIX32TOPRINT(temp));
 315         }
 316         DBG_LOTS("fans = %d, t_max = %d.%03d\n", target, FIX32TOPRINT(t_max));
 317
 318         /* Darwin limits decrease to 20 per iteration */
 319         if (target < (cpu_last_target - 20))
 320                 target = cpu_last_target - 20;
 321         cpu_last_target = target;
 322         for (cpu = 0; cpu < nr_cores; ++cpu)
 323                 cpu_pid[cpu].target = target;
 324
 325         /* Handle possible overtemps */
 326         if (cpu_check_overtemp(t_max))
 327                 return;
 328
 329         /* Set fans */
 330         for (i = 0; i < NR_CPU_FANS; ++i) {
 331                 ct = cpu_fans[i];
 332                 if (ct == NULL)
 333                         continue;
 334                 err = ct->ops->set_value(ct, target * cpu_fan_scale[i] / 100);
 335                 if (err) {
 336                         printk(KERN_WARNING "windfarm: fan %s reports "
 337                                "error %d\n", ct->name, err);
 338                         failure_state |= FAILURE_FAN;
 339                         break;
 340                 }
 341         }
 342 }
 343
 344 /* Backside/U4 fan */
 345 static struct wf_pid_param backside_param = {
 346         .interval       = 5,
 347         .history_len    = 2,
 348         .gd             = 48 << 20,
 349         .gp             = 5 << 20,
 350         .gr             = 0,
 351         .itarget        = 64 << 16,
 352         .additive       = 1,
 353 };
 354
 355 static void backside_fan_tick(void)
 356 {
 357         s32 temp;
 358         int speed;
 359         int err;
 360
 361         if (!backside_fan || !u4_temp)
 362                 return;
 363         if (!backside_tick) {
 364                 /* first time; initialize things */
 365                 printk(KERN_INFO "windfarm: Backside control loop started.\n");
 366                 backside_param.min = backside_fan->ops->get_min(backside_fan);
 367                 backside_param.max = backside_fan->ops->get_max(backside_fan);
 368                 wf_pid_init(&backside_pid, &backside_param);
 369                 backside_tick = 1;
 370         }
 371         if (--backside_tick > 0)
 372                 return;
 373         backside_tick = backside_pid.param.interval;
 374
 375         err = u4_temp->ops->get_value(u4_temp, &temp);
 376         if (err) {
 377                 printk(KERN_WARNING "windfarm: U4 temp sensor error %d\n",
 378                        err);
 379                 failure_state |= FAILURE_SENSOR;
 380                 wf_control_set_max(backside_fan);
 381                 return;
 382         }
 383         speed = wf_pid_run(&backside_pid, temp);
 384         DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
 385                  FIX32TOPRINT(temp), speed);
 386
 387         err = backside_fan->ops->set_value(backside_fan, speed);
 388         if (err) {
 389                 printk(KERN_WARNING "windfarm: backside fan error %d\n", err);
 390                 failure_state |= FAILURE_FAN;
 391         }
 392 }
 393
 394 /* Drive bay fan */
 395 static struct wf_pid_param drive_bay_prm = {
 396         .interval       = 5,
 397         .history_len    = 2,
 398         .gd             = 30 << 20,
 399         .gp             = 5 << 20,
 400         .gr             = 0,
 401         .itarget        = 40 << 16,
 402         .additive       = 1,
 403 };
 404
 405 static void drive_bay_fan_tick(void)
 406 {
 407         s32 temp;
 408         int speed;
 409         int err;
 410
 411         if (!drive_bay_fan || !hd_temp)
 412                 return;
 413         if (!drive_bay_tick) {
 414                 /* first time; initialize things */
 415                 printk(KERN_INFO "windfarm: Drive bay control loop started.\n");
 416                 drive_bay_prm.min = drive_bay_fan->ops->get_min(drive_bay_fan);
 417                 drive_bay_prm.max = drive_bay_fan->ops->get_max(drive_bay_fan);
 418                 wf_pid_init(&drive_bay_pid, &drive_bay_prm);
 419                 drive_bay_tick = 1;
 420         }
 421         if (--drive_bay_tick > 0)
 422                 return;
 423         drive_bay_tick = drive_bay_pid.param.interval;
 424
 425         err = hd_temp->ops->get_value(hd_temp, &temp);
 426         if (err) {
 427                 printk(KERN_WARNING "windfarm: drive bay temp sensor "
 428                        "error %d\n", err);
 429                 failure_state |= FAILURE_SENSOR;
 430                 wf_control_set_max(drive_bay_fan);
 431                 return;
 432         }
 433         speed = wf_pid_run(&drive_bay_pid, temp);
 434         DBG_LOTS("drive_bay PID temp=%d.%.3d speed=%d\n",
 435                  FIX32TOPRINT(temp), speed);
 436
 437         err = drive_bay_fan->ops->set_value(drive_bay_fan, speed);
 438         if (err) {
 439                 printk(KERN_WARNING "windfarm: drive bay fan error %d\n", err);
 440                 failure_state |= FAILURE_FAN;
 441         }
 442 }
 443
 444 /* PCI slots area fan */
 445 /* This makes the fan speed proportional to the power consumed */
 446 static struct wf_pid_param slots_param = {
 447         .interval       = 1,
 448         .history_len    = 2,
 449         .gd             = 0,
 450         .gp             = 0,
 451         .gr             = 0x1277952,
 452         .itarget        = 0,
 453         .min            = 1560,
 454         .max            = 3510,
 455 };
 456
 457 static void slots_fan_tick(void)
 458 {
 459         s32 power;
 460         int speed;
 461         int err;
 462
 463         if (!slots_fan || !slots_power)
 464                 return;
 465         if (!slots_started) {
 466                 /* first time; initialize things */
 467                 printk(KERN_INFO "windfarm: Slots control loop started.\n");
 468                 wf_pid_init(&slots_pid, &slots_param);
 469                 slots_started = true;
 470         }
 471
 472         err = slots_power->ops->get_value(slots_power, &power);
 473         if (err) {
 474                 printk(KERN_WARNING "windfarm: slots power sensor error %d\n",
 475                        err);
 476                 failure_state |= FAILURE_SENSOR;
 477                 wf_control_set_max(slots_fan);
 478                 return;
 479         }
 480         speed = wf_pid_run(&slots_pid, power);
 481         DBG_LOTS("slots PID power=%d.%.3d speed=%d\n",
 482                  FIX32TOPRINT(power), speed);
 483
 484         err = slots_fan->ops->set_value(slots_fan, speed);
 485         if (err) {
 486                 printk(KERN_WARNING "windfarm: slots fan error %d\n", err);
 487                 failure_state |= FAILURE_FAN;
 488         }
 489 }
 490
 491 static void set_fail_state(void)
 492 {
 493         int i;
 494
 495         if (cpufreq_clamp)
 496                 wf_control_set_max(cpufreq_clamp);
 497         for (i = 0; i < NR_CPU_FANS; ++i)
 498                 if (cpu_fans[i])
 499                         wf_control_set_max(cpu_fans[i]);
 500         if (backside_fan)
 501                 wf_control_set_max(backside_fan);
 502         if (slots_fan)
 503                 wf_control_set_max(slots_fan);
 504         if (drive_bay_fan)
 505                 wf_control_set_max(drive_bay_fan);
 506 }
 507
 508 static void pm112_tick(void)
 509 {
 510         int i, last_failure;
 511
 512         if (!started) {
 513                 started = true;
 514                 printk(KERN_INFO "windfarm: CPUs control loops started.\n");
 515                 for (i = 0; i < nr_cores; ++i) {
 516                         if (create_cpu_loop(i) < 0) {
 517                                 failure_state = FAILURE_PERM;
 518                                 set_fail_state();
 519                                 break;
 520                         }
 521                 }
 522                 DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax));
 523
 524 #ifdef HACKED_OVERTEMP
 525                 cpu_all_tmax = 60 << 16;
 526 #endif
 527         }
 528
 529         /* Permanent failure, bail out */
 530         if (failure_state & FAILURE_PERM)
 531                 return;
 532         /* Clear all failure bits except low overtemp which will be eventually
 533          * cleared by the control loop itself
 534          */
 535         last_failure = failure_state;
 536         failure_state &= FAILURE_LOW_OVERTEMP;
 537         cpu_fans_tick();
 538         backside_fan_tick();
 539         slots_fan_tick();
 540         drive_bay_fan_tick();
 541
 542         DBG_LOTS("last_failure: 0x%x, failure_state: %x\n",
 543                  last_failure, failure_state);
 544
 545         /* Check for failures. Any failure causes cpufreq clamping */
 546         if (failure_state && last_failure == 0 && cpufreq_clamp)
 547                 wf_control_set_max(cpufreq_clamp);
 548         if (failure_state == 0 && last_failure && cpufreq_clamp)
 549                 wf_control_set_min(cpufreq_clamp);
 550
 551         /* That's it for now, we might want to deal with other failures
 552          * differently in the future though
 553          */
 554 }
 555
 556 static void pm112_new_control(struct wf_control *ct)
 557 {
 558         int i, max_exhaust;
 559
 560         if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {
 561                 if (wf_get_control(ct) == 0)
 562                         cpufreq_clamp = ct;
 563         }
 564
 565         for (i = 0; i < NR_CPU_FANS; ++i) {
 566                 if (!strcmp(ct->name, cpu_fan_names[i])) {
 567                         if (cpu_fans[i] == NULL && wf_get_control(ct) == 0)
 568                                 cpu_fans[i] = ct;
 569                         break;
 570                 }
 571         }
 572         if (i >= NR_CPU_FANS) {
 573                 /* not a CPU fan, try the others */
 574                 if (!strcmp(ct->name, "backside-fan")) {
 575                         if (backside_fan == NULL && wf_get_control(ct) == 0)
 576                                 backside_fan = ct;
 577                 } else if (!strcmp(ct->name, "slots-fan")) {
 578                         if (slots_fan == NULL && wf_get_control(ct) == 0)
 579                                 slots_fan = ct;
 580                 } else if (!strcmp(ct->name, "drive-bay-fan")) {
 581                         if (drive_bay_fan == NULL && wf_get_control(ct) == 0)
 582                                 drive_bay_fan = ct;
 583                 }
 584                 return;
 585         }
 586
 587         for (i = 0; i < CPU_FANS_REQD; ++i)
 588                 if (cpu_fans[i] == NULL)
 589                         return;
 590
 591         /* work out pump scaling factors */
 592         max_exhaust = cpu_fans[0]->ops->get_max(cpu_fans[0]);
 593         for (i = FIRST_PUMP; i <= LAST_PUMP; ++i)
 594                 if ((ct = cpu_fans[i]) != NULL)
 595                         cpu_fan_scale[i] =
 596                                 ct->ops->get_max(ct) * 100 / max_exhaust;
 597
 598         have_all_controls = 1;
 599 }
 600
 601 static void pm112_new_sensor(struct wf_sensor *sr)
 602 {
 603         unsigned int i;
 604
 605         if (!strncmp(sr->name, "cpu-temp-", 9)) {
 606                 i = sr->name[9] - '0';
 607                 if (sr->name[10] == 0 && i < NR_CORES &&
 608                     sens_cpu_temp[i] == NULL && wf_get_sensor(sr) == 0)
 609                         sens_cpu_temp[i] = sr;
 610
 611         } else if (!strncmp(sr->name, "cpu-power-", 10)) {
 612                 i = sr->name[10] - '0';
 613                 if (sr->name[11] == 0 && i < NR_CORES &&
 614                     sens_cpu_power[i] == NULL && wf_get_sensor(sr) == 0)
 615                         sens_cpu_power[i] = sr;
 616         } else if (!strcmp(sr->name, "hd-temp")) {
 617                 if (hd_temp == NULL && wf_get_sensor(sr) == 0)
 618                         hd_temp = sr;
 619         } else if (!strcmp(sr->name, "slots-power")) {
 620                 if (slots_power == NULL && wf_get_sensor(sr) == 0)
 621                         slots_power = sr;
 622         } else if (!strcmp(sr->name, "backside-temp")) {
 623                 if (u4_temp == NULL && wf_get_sensor(sr) == 0)
 624                         u4_temp = sr;
 625         } else
 626                 return;
 627
 628         /* check if we have all the sensors we need */
 629         for (i = 0; i < nr_cores; ++i)
 630                 if (sens_cpu_temp[i] == NULL || sens_cpu_power[i] == NULL)
 631                         return;
 632
 633         have_all_sensors = 1;
 634 }
 635
 636 static int pm112_wf_notify(struct notifier_block *self,
 637                            unsigned long event, void *data)
 638 {
 639         switch (event) {
 640         case WF_EVENT_NEW_SENSOR:
 641                 pm112_new_sensor(data);
 642                 break;
 643         case WF_EVENT_NEW_CONTROL:
 644                 pm112_new_control(data);
 645                 break;
 646         case WF_EVENT_TICK:
 647                 if (have_all_controls && have_all_sensors)
 648                         pm112_tick();
 649         }
 650         return 0;
 651 }
 652
 653 static struct notifier_block pm112_events = {
 654         .notifier_call = pm112_wf_notify,
 655 };
 656
 657 static int wf_pm112_probe(struct platform_device *dev)
 658 {
 659         wf_register_client(&pm112_events);
 660         return 0;
 661 }
 662
 663 static int wf_pm112_remove(struct platform_device *dev)
 664 {
 665         wf_unregister_client(&pm112_events);
 666         /* should release all sensors and controls */
 667         return 0;
 668 }
 669
 670 static struct platform_driver wf_pm112_driver = {
 671         .probe = wf_pm112_probe,
 672         .remove = wf_pm112_remove,
 673         .driver = {
 674                 .name = "windfarm",
 675         },
 676 };
 677
 678 static int __init wf_pm112_init(void)
 679 {
 680         struct device_node *cpu;
 681
 682         if (!of_machine_is_compatible("PowerMac11,2"))
 683                 return -ENODEV;
 684
 685         /* Count the number of CPU cores */
 686         nr_cores = 0;
 687         for_each_node_by_type(cpu, "cpu")
 688                 ++nr_cores;
 689
 690         printk(KERN_INFO "windfarm: initializing for dual-core desktop G5\n");
 691
 692 #ifdef MODULE
 693         request_module("windfarm_smu_controls");
 694         request_module("windfarm_smu_sensors");
 695         request_module("windfarm_smu_sat");
 696         request_module("windfarm_lm75_sensor");
 697         request_module("windfarm_max6690_sensor");
 698         request_module("windfarm_cpufreq_clamp");
 699
 700 #endif /* MODULE */
 701
 702         platform_driver_register(&wf_pm112_driver);
 703         return 0;
 704 }
 705
 706 static void __exit wf_pm112_exit(void)
 707 {
 708         platform_driver_unregister(&wf_pm112_driver);
 709 }
 710
 711 module_init(wf_pm112_init);
 712 module_exit(wf_pm112_exit);
 713
 714 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
 715 MODULE_DESCRIPTION("Thermal control for PowerMac11,2");
 716 MODULE_LICENSE("GPL");
 717 MODULE_ALIAS("platform:windfarm");