linux/drivers/macintosh/windfarm_pm81.c
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   1/*
   2 * Windfarm PowerMac thermal control. iMac G5
   3 *
   4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   5 *                    <benh@kernel.crashing.org>
   6 *
   7 * Released under the term of the GNU GPL v2.
   8 *
   9 * The algorithm used is the PID control algorithm, used the same
  10 * way the published Darwin code does, using the same values that
  11 * are present in the Darwin 8.2 snapshot property lists (note however
  12 * that none of the code has been re-used, it's a complete re-implementation
  13 *
  14 * The various control loops found in Darwin config file are:
  15 *
  16 * PowerMac8,1 and PowerMac8,2
  17 * ===========================
  18 *
  19 * System Fans control loop. Different based on models. In addition to the
  20 * usual PID algorithm, the control loop gets 2 additional pairs of linear
  21 * scaling factors (scale/offsets) expressed as 4.12 fixed point values
  22 * signed offset, unsigned scale)
  23 *
  24 * The targets are modified such as:
  25 *  - the linked control (second control) gets the target value as-is
  26 *    (typically the drive fan)
  27 *  - the main control (first control) gets the target value scaled with
  28 *    the first pair of factors, and is then modified as below
  29 *  - the value of the target of the CPU Fan control loop is retrieved,
  30 *    scaled with the second pair of factors, and the max of that and
  31 *    the scaled target is applied to the main control.
  32 *
  33 * # model_id: 2
  34 *   controls       : system-fan, drive-bay-fan
  35 *   sensors        : hd-temp
  36 *   PID params     : G_d = 0x15400000
  37 *                    G_p = 0x00200000
  38 *                    G_r = 0x000002fd
  39 *                    History = 2 entries
  40 *                    Input target = 0x3a0000
  41 *                    Interval = 5s
  42 *   linear-factors : offset = 0xff38 scale  = 0x0ccd
  43 *                    offset = 0x0208 scale  = 0x07ae
  44 *
  45 * # model_id: 3
  46 *   controls       : system-fan, drive-bay-fan
  47 *   sensors        : hd-temp
  48 *   PID params     : G_d = 0x08e00000
  49 *                    G_p = 0x00566666
  50 *                    G_r = 0x0000072b
  51 *                    History = 2 entries
  52 *                    Input target = 0x350000
  53 *                    Interval = 5s
  54 *   linear-factors : offset = 0xff38 scale  = 0x0ccd
  55 *                    offset = 0x0000 scale  = 0x0000
  56 *
  57 * # model_id: 5
  58 *   controls       : system-fan
  59 *   sensors        : hd-temp
  60 *   PID params     : G_d = 0x15400000
  61 *                    G_p = 0x00233333
  62 *                    G_r = 0x000002fd
  63 *                    History = 2 entries
  64 *                    Input target = 0x3a0000
  65 *                    Interval = 5s
  66 *   linear-factors : offset = 0x0000 scale  = 0x1000
  67 *                    offset = 0x0091 scale  = 0x0bae
  68 *
  69 * CPU Fan control loop. The loop is identical for all models. it
  70 * has an additional pair of scaling factor. This is used to scale the
  71 * systems fan control loop target result (the one before it gets scaled
  72 * by the System Fans control loop itself). Then, the max value of the
  73 * calculated target value and system fan value is sent to the fans
  74 *
  75 *   controls       : cpu-fan
  76 *   sensors        : cpu-temp cpu-power
  77 *   PID params     : From SMU sdb partition
  78 *   linear-factors : offset = 0xfb50 scale  = 0x1000
  79 *
  80 * CPU Slew control loop. Not implemented. The cpufreq driver in linux is
  81 * completely separate for now, though we could find a way to link it, either
  82 * as a client reacting to overtemp notifications, or directling monitoring
  83 * the CPU temperature
  84 *
  85 * WARNING ! The CPU control loop requires the CPU tmax for the current
  86 * operating point. However, we currently are completely separated from
  87 * the cpufreq driver and thus do not know what the current operating
  88 * point is. Fortunately, we also do not have any hardware supporting anything
  89 * but operating point 0 at the moment, thus we just peek that value directly
  90 * from the SDB partition. If we ever end up with actually slewing the system
  91 * clock and thus changing operating points, we'll have to find a way to
  92 * communicate with the CPU freq driver;
  93 *
  94 */
  95
  96#include <linux/types.h>
  97#include <linux/errno.h>
  98#include <linux/kernel.h>
  99#include <linux/delay.h>
 100#include <linux/slab.h>
 101#include <linux/init.h>
 102#include <linux/spinlock.h>
 103#include <linux/wait.h>
 104#include <linux/kmod.h>
 105#include <linux/device.h>
 106#include <linux/platform_device.h>
 107#include <asm/prom.h>
 108#include <asm/machdep.h>
 109#include <asm/io.h>
 110#include <asm/sections.h>
 111#include <asm/smu.h>
 112
 113#include "windfarm.h"
 114#include "windfarm_pid.h"
 115
 116#define VERSION "0.4"
 117
 118#undef DEBUG
 119
 120#ifdef DEBUG
 121#define DBG(args...)    printk(args)
 122#else
 123#define DBG(args...)    do { } while(0)
 124#endif
 125
 126/* define this to force CPU overtemp to 74 degree, useful for testing
 127 * the overtemp code
 128 */
 129#undef HACKED_OVERTEMP
 130
 131static int wf_smu_mach_model;   /* machine model id */
 132
 133/* Controls & sensors */
 134static struct wf_sensor *sensor_cpu_power;
 135static struct wf_sensor *sensor_cpu_temp;
 136static struct wf_sensor *sensor_hd_temp;
 137static struct wf_control *fan_cpu_main;
 138static struct wf_control *fan_hd;
 139static struct wf_control *fan_system;
 140static struct wf_control *cpufreq_clamp;
 141
 142/* Set to kick the control loop into life */
 143static int wf_smu_all_controls_ok, wf_smu_all_sensors_ok, wf_smu_started;
 144
 145/* Failure handling.. could be nicer */
 146#define FAILURE_FAN             0x01
 147#define FAILURE_SENSOR          0x02
 148#define FAILURE_OVERTEMP        0x04
 149
 150static unsigned int wf_smu_failure_state;
 151static int wf_smu_readjust, wf_smu_skipping;
 152static bool wf_smu_overtemp;
 153
 154/*
 155 * ****** System Fans Control Loop ******
 156 *
 157 */
 158
 159/* Parameters for the System Fans control loop. Parameters
 160 * not in this table such as interval, history size, ...
 161 * are common to all versions and thus hard coded for now.
 162 */
 163struct wf_smu_sys_fans_param {
 164        int     model_id;
 165        s32     itarget;
 166        s32     gd, gp, gr;
 167
 168        s16     offset0;
 169        u16     scale0;
 170        s16     offset1;
 171        u16     scale1;
 172};
 173
 174#define WF_SMU_SYS_FANS_INTERVAL        5
 175#define WF_SMU_SYS_FANS_HISTORY_SIZE    2
 176
 177/* State data used by the system fans control loop
 178 */
 179struct wf_smu_sys_fans_state {
 180        int                     ticks;
 181        s32                     sys_setpoint;
 182        s32                     hd_setpoint;
 183        s16                     offset0;
 184        u16                     scale0;
 185        s16                     offset1;
 186        u16                     scale1;
 187        struct wf_pid_state     pid;
 188};
 189
 190/*
 191 * Configs for SMU System Fan control loop
 192 */
 193static struct wf_smu_sys_fans_param wf_smu_sys_all_params[] = {
 194        /* Model ID 2 */
 195        {
 196                .model_id       = 2,
 197                .itarget        = 0x3a0000,
 198                .gd             = 0x15400000,
 199                .gp             = 0x00200000,
 200                .gr             = 0x000002fd,
 201                .offset0        = 0xff38,
 202                .scale0         = 0x0ccd,
 203                .offset1        = 0x0208,
 204                .scale1         = 0x07ae,
 205        },
 206        /* Model ID 3 */
 207        {
 208                .model_id       = 3,
 209                .itarget        = 0x350000,
 210                .gd             = 0x08e00000,
 211                .gp             = 0x00566666,
 212                .gr             = 0x0000072b,
 213                .offset0        = 0xff38,
 214                .scale0         = 0x0ccd,
 215                .offset1        = 0x0000,
 216                .scale1         = 0x0000,
 217        },
 218        /* Model ID 5 */
 219        {
 220                .model_id       = 5,
 221                .itarget        = 0x3a0000,
 222                .gd             = 0x15400000,
 223                .gp             = 0x00233333,
 224                .gr             = 0x000002fd,
 225                .offset0        = 0x0000,
 226                .scale0         = 0x1000,
 227                .offset1        = 0x0091,
 228                .scale1         = 0x0bae,
 229        },
 230};
 231#define WF_SMU_SYS_FANS_NUM_CONFIGS ARRAY_SIZE(wf_smu_sys_all_params)
 232
 233static struct wf_smu_sys_fans_state *wf_smu_sys_fans;
 234
 235/*
 236 * ****** CPU Fans Control Loop ******
 237 *
 238 */
 239
 240
 241#define WF_SMU_CPU_FANS_INTERVAL        1
 242#define WF_SMU_CPU_FANS_MAX_HISTORY     16
 243#define WF_SMU_CPU_FANS_SIBLING_SCALE   0x00001000
 244#define WF_SMU_CPU_FANS_SIBLING_OFFSET  0xfffffb50
 245
 246/* State data used by the cpu fans control loop
 247 */
 248struct wf_smu_cpu_fans_state {
 249        int                     ticks;
 250        s32                     cpu_setpoint;
 251        s32                     scale;
 252        s32                     offset;
 253        struct wf_cpu_pid_state pid;
 254};
 255
 256static struct wf_smu_cpu_fans_state *wf_smu_cpu_fans;
 257
 258
 259
 260/*
 261 * ***** Implementation *****
 262 *
 263 */
 264
 265static void wf_smu_create_sys_fans(void)
 266{
 267        struct wf_smu_sys_fans_param *param = NULL;
 268        struct wf_pid_param pid_param;
 269        int i;
 270
 271        /* First, locate the params for this model */
 272        for (i = 0; i < WF_SMU_SYS_FANS_NUM_CONFIGS; i++)
 273                if (wf_smu_sys_all_params[i].model_id == wf_smu_mach_model) {
 274                        param = &wf_smu_sys_all_params[i];
 275                        break;
 276                }
 277
 278        /* No params found, put fans to max */
 279        if (param == NULL) {
 280                printk(KERN_WARNING "windfarm: System fan config not found "
 281                       "for this machine model, max fan speed\n");
 282                goto fail;
 283        }
 284
 285        /* Alloc & initialize state */
 286        wf_smu_sys_fans = kmalloc(sizeof(struct wf_smu_sys_fans_state),
 287                                  GFP_KERNEL);
 288        if (wf_smu_sys_fans == NULL) {
 289                printk(KERN_WARNING "windfarm: Memory allocation error"
 290                       " max fan speed\n");
 291                goto fail;
 292        }
 293        wf_smu_sys_fans->ticks = 1;
 294        wf_smu_sys_fans->scale0 = param->scale0;
 295        wf_smu_sys_fans->offset0 = param->offset0;
 296        wf_smu_sys_fans->scale1 = param->scale1;
 297        wf_smu_sys_fans->offset1 = param->offset1;
 298
 299        /* Fill PID params */
 300        pid_param.gd = param->gd;
 301        pid_param.gp = param->gp;
 302        pid_param.gr = param->gr;
 303        pid_param.interval = WF_SMU_SYS_FANS_INTERVAL;
 304        pid_param.history_len = WF_SMU_SYS_FANS_HISTORY_SIZE;
 305        pid_param.itarget = param->itarget;
 306        pid_param.min = wf_control_get_min(fan_system);
 307        pid_param.max = wf_control_get_max(fan_system);
 308        if (fan_hd) {
 309                pid_param.min =
 310                        max(pid_param.min, wf_control_get_min(fan_hd));
 311                pid_param.max =
 312                        min(pid_param.max, wf_control_get_max(fan_hd));
 313        }
 314        wf_pid_init(&wf_smu_sys_fans->pid, &pid_param);
 315
 316        DBG("wf: System Fan control initialized.\n");
 317        DBG("    itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
 318            FIX32TOPRINT(pid_param.itarget), pid_param.min, pid_param.max);
 319        return;
 320
 321 fail:
 322
 323        if (fan_system)
 324                wf_control_set_max(fan_system);
 325        if (fan_hd)
 326                wf_control_set_max(fan_hd);
 327}
 328
 329static void wf_smu_sys_fans_tick(struct wf_smu_sys_fans_state *st)
 330{
 331        s32 new_setpoint, temp, scaled, cputarget;
 332        int rc;
 333
 334        if (--st->ticks != 0) {
 335                if (wf_smu_readjust)
 336                        goto readjust;
 337                return;
 338        }
 339        st->ticks = WF_SMU_SYS_FANS_INTERVAL;
 340
 341        rc = wf_sensor_get(sensor_hd_temp, &temp);
 342        if (rc) {
 343                printk(KERN_WARNING "windfarm: HD temp sensor error %d\n",
 344                       rc);
 345                wf_smu_failure_state |= FAILURE_SENSOR;
 346                return;
 347        }
 348
 349        DBG("wf_smu: System Fans tick ! HD temp: %d.%03d\n",
 350            FIX32TOPRINT(temp));
 351
 352        if (temp > (st->pid.param.itarget + 0x50000))
 353                wf_smu_failure_state |= FAILURE_OVERTEMP;
 354
 355        new_setpoint = wf_pid_run(&st->pid, temp);
 356
 357        DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint);
 358
 359        scaled = ((((s64)new_setpoint) * (s64)st->scale0) >> 12) + st->offset0;
 360
 361        DBG("wf_smu: scaled setpoint: %d RPM\n", (int)scaled);
 362
 363        cputarget = wf_smu_cpu_fans ? wf_smu_cpu_fans->pid.target : 0;
 364        cputarget = ((((s64)cputarget) * (s64)st->scale1) >> 12) + st->offset1;
 365        scaled = max(scaled, cputarget);
 366        scaled = max(scaled, st->pid.param.min);
 367        scaled = min(scaled, st->pid.param.max);
 368
 369        DBG("wf_smu: adjusted setpoint: %d RPM\n", (int)scaled);
 370
 371        if (st->sys_setpoint == scaled && new_setpoint == st->hd_setpoint)
 372                return;
 373        st->sys_setpoint = scaled;
 374        st->hd_setpoint = new_setpoint;
 375 readjust:
 376        if (fan_system && wf_smu_failure_state == 0) {
 377                rc = wf_control_set(fan_system, st->sys_setpoint);
 378                if (rc) {
 379                        printk(KERN_WARNING "windfarm: Sys fan error %d\n",
 380                               rc);
 381                        wf_smu_failure_state |= FAILURE_FAN;
 382                }
 383        }
 384        if (fan_hd && wf_smu_failure_state == 0) {
 385                rc = wf_control_set(fan_hd, st->hd_setpoint);
 386                if (rc) {
 387                        printk(KERN_WARNING "windfarm: HD fan error %d\n",
 388                               rc);
 389                        wf_smu_failure_state |= FAILURE_FAN;
 390                }
 391        }
 392}
 393
 394static void wf_smu_create_cpu_fans(void)
 395{
 396        struct wf_cpu_pid_param pid_param;
 397        const struct smu_sdbp_header *hdr;
 398        struct smu_sdbp_cpupiddata *piddata;
 399        struct smu_sdbp_fvt *fvt;
 400        s32 tmax, tdelta, maxpow, powadj;
 401
 402        /* First, locate the PID params in SMU SBD */
 403        hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
 404        if (hdr == 0) {
 405                printk(KERN_WARNING "windfarm: CPU PID fan config not found "
 406                       "max fan speed\n");
 407                goto fail;
 408        }
 409        piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
 410
 411        /* Get the FVT params for operating point 0 (the only supported one
 412         * for now) in order to get tmax
 413         */
 414        hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
 415        if (hdr) {
 416                fvt = (struct smu_sdbp_fvt *)&hdr[1];
 417                tmax = ((s32)fvt->maxtemp) << 16;
 418        } else
 419                tmax = 0x5e0000; /* 94 degree default */
 420
 421        /* Alloc & initialize state */
 422        wf_smu_cpu_fans = kmalloc(sizeof(struct wf_smu_cpu_fans_state),
 423                                  GFP_KERNEL);
 424        if (wf_smu_cpu_fans == NULL)
 425                goto fail;
 426        wf_smu_cpu_fans->ticks = 1;
 427
 428        wf_smu_cpu_fans->scale = WF_SMU_CPU_FANS_SIBLING_SCALE;
 429        wf_smu_cpu_fans->offset = WF_SMU_CPU_FANS_SIBLING_OFFSET;
 430
 431        /* Fill PID params */
 432        pid_param.interval = WF_SMU_CPU_FANS_INTERVAL;
 433        pid_param.history_len = piddata->history_len;
 434        if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
 435                printk(KERN_WARNING "windfarm: History size overflow on "
 436                       "CPU control loop (%d)\n", piddata->history_len);
 437                pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
 438        }
 439        pid_param.gd = piddata->gd;
 440        pid_param.gp = piddata->gp;
 441        pid_param.gr = piddata->gr / pid_param.history_len;
 442
 443        tdelta = ((s32)piddata->target_temp_delta) << 16;
 444        maxpow = ((s32)piddata->max_power) << 16;
 445        powadj = ((s32)piddata->power_adj) << 16;
 446
 447        pid_param.tmax = tmax;
 448        pid_param.ttarget = tmax - tdelta;
 449        pid_param.pmaxadj = maxpow - powadj;
 450
 451        pid_param.min = wf_control_get_min(fan_cpu_main);
 452        pid_param.max = wf_control_get_max(fan_cpu_main);
 453
 454        wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param);
 455
 456        DBG("wf: CPU Fan control initialized.\n");
 457        DBG("    ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
 458            FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
 459            pid_param.min, pid_param.max);
 460
 461        return;
 462
 463 fail:
 464        printk(KERN_WARNING "windfarm: CPU fan config not found\n"
 465               "for this machine model, max fan speed\n");
 466
 467        if (cpufreq_clamp)
 468                wf_control_set_max(cpufreq_clamp);
 469        if (fan_cpu_main)
 470                wf_control_set_max(fan_cpu_main);
 471}
 472
 473static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state *st)
 474{
 475        s32 new_setpoint, temp, power, systarget;
 476        int rc;
 477
 478        if (--st->ticks != 0) {
 479                if (wf_smu_readjust)
 480                        goto readjust;
 481                return;
 482        }
 483        st->ticks = WF_SMU_CPU_FANS_INTERVAL;
 484
 485        rc = wf_sensor_get(sensor_cpu_temp, &temp);
 486        if (rc) {
 487                printk(KERN_WARNING "windfarm: CPU temp sensor error %d\n",
 488                       rc);
 489                wf_smu_failure_state |= FAILURE_SENSOR;
 490                return;
 491        }
 492
 493        rc = wf_sensor_get(sensor_cpu_power, &power);
 494        if (rc) {
 495                printk(KERN_WARNING "windfarm: CPU power sensor error %d\n",
 496                       rc);
 497                wf_smu_failure_state |= FAILURE_SENSOR;
 498                return;
 499        }
 500
 501        DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n",
 502            FIX32TOPRINT(temp), FIX32TOPRINT(power));
 503
 504#ifdef HACKED_OVERTEMP
 505        if (temp > 0x4a0000)
 506                wf_smu_failure_state |= FAILURE_OVERTEMP;
 507#else
 508        if (temp > st->pid.param.tmax)
 509                wf_smu_failure_state |= FAILURE_OVERTEMP;
 510#endif
 511        new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
 512
 513        DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint);
 514
 515        systarget = wf_smu_sys_fans ? wf_smu_sys_fans->pid.target : 0;
 516        systarget = ((((s64)systarget) * (s64)st->scale) >> 12)
 517                + st->offset;
 518        new_setpoint = max(new_setpoint, systarget);
 519        new_setpoint = max(new_setpoint, st->pid.param.min);
 520        new_setpoint = min(new_setpoint, st->pid.param.max);
 521
 522        DBG("wf_smu: adjusted setpoint: %d RPM\n", (int)new_setpoint);
 523
 524        if (st->cpu_setpoint == new_setpoint)
 525                return;
 526        st->cpu_setpoint = new_setpoint;
 527 readjust:
 528        if (fan_cpu_main && wf_smu_failure_state == 0) {
 529                rc = wf_control_set(fan_cpu_main, st->cpu_setpoint);
 530                if (rc) {
 531                        printk(KERN_WARNING "windfarm: CPU main fan"
 532                               " error %d\n", rc);
 533                        wf_smu_failure_state |= FAILURE_FAN;
 534                }
 535        }
 536}
 537
 538/*
 539 * ****** Setup / Init / Misc ... ******
 540 *
 541 */
 542
 543static void wf_smu_tick(void)
 544{
 545        unsigned int last_failure = wf_smu_failure_state;
 546        unsigned int new_failure;
 547
 548        if (!wf_smu_started) {
 549                DBG("wf: creating control loops !\n");
 550                wf_smu_create_sys_fans();
 551                wf_smu_create_cpu_fans();
 552                wf_smu_started = 1;
 553        }
 554
 555        /* Skipping ticks */
 556        if (wf_smu_skipping && --wf_smu_skipping)
 557                return;
 558
 559        wf_smu_failure_state = 0;
 560        if (wf_smu_sys_fans)
 561                wf_smu_sys_fans_tick(wf_smu_sys_fans);
 562        if (wf_smu_cpu_fans)
 563                wf_smu_cpu_fans_tick(wf_smu_cpu_fans);
 564
 565        wf_smu_readjust = 0;
 566        new_failure = wf_smu_failure_state & ~last_failure;
 567
 568        /* If entering failure mode, clamp cpufreq and ramp all
 569         * fans to full speed.
 570         */
 571        if (wf_smu_failure_state && !last_failure) {
 572                if (cpufreq_clamp)
 573                        wf_control_set_max(cpufreq_clamp);
 574                if (fan_system)
 575                        wf_control_set_max(fan_system);
 576                if (fan_cpu_main)
 577                        wf_control_set_max(fan_cpu_main);
 578                if (fan_hd)
 579                        wf_control_set_max(fan_hd);
 580        }
 581
 582        /* If leaving failure mode, unclamp cpufreq and readjust
 583         * all fans on next iteration
 584         */
 585        if (!wf_smu_failure_state && last_failure) {
 586                if (cpufreq_clamp)
 587                        wf_control_set_min(cpufreq_clamp);
 588                wf_smu_readjust = 1;
 589        }
 590
 591        /* Overtemp condition detected, notify and start skipping a couple
 592         * ticks to let the temperature go down
 593         */
 594        if (new_failure & FAILURE_OVERTEMP) {
 595                wf_set_overtemp();
 596                wf_smu_skipping = 2;
 597                wf_smu_overtemp = true;
 598        }
 599
 600        /* We only clear the overtemp condition if overtemp is cleared
 601         * _and_ no other failure is present. Since a sensor error will
 602         * clear the overtemp condition (can't measure temperature) at
 603         * the control loop levels, but we don't want to keep it clear
 604         * here in this case
 605         */
 606        if (!wf_smu_failure_state && wf_smu_overtemp) {
 607                wf_clear_overtemp();
 608                wf_smu_overtemp = false;
 609        }
 610}
 611
 612static void wf_smu_new_control(struct wf_control *ct)
 613{
 614        if (wf_smu_all_controls_ok)
 615                return;
 616
 617        if (fan_cpu_main == NULL && !strcmp(ct->name, "cpu-fan")) {
 618                if (wf_get_control(ct) == 0)
 619                        fan_cpu_main = ct;
 620        }
 621
 622        if (fan_system == NULL && !strcmp(ct->name, "system-fan")) {
 623                if (wf_get_control(ct) == 0)
 624                        fan_system = ct;
 625        }
 626
 627        if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {
 628                if (wf_get_control(ct) == 0)
 629                        cpufreq_clamp = ct;
 630        }
 631
 632        /* Darwin property list says the HD fan is only for model ID
 633         * 0, 1, 2 and 3
 634         */
 635
 636        if (wf_smu_mach_model > 3) {
 637                if (fan_system && fan_cpu_main && cpufreq_clamp)
 638                        wf_smu_all_controls_ok = 1;
 639                return;
 640        }
 641
 642        if (fan_hd == NULL && !strcmp(ct->name, "drive-bay-fan")) {
 643                if (wf_get_control(ct) == 0)
 644                        fan_hd = ct;
 645        }
 646
 647        if (fan_system && fan_hd && fan_cpu_main && cpufreq_clamp)
 648                wf_smu_all_controls_ok = 1;
 649}
 650
 651static void wf_smu_new_sensor(struct wf_sensor *sr)
 652{
 653        if (wf_smu_all_sensors_ok)
 654                return;
 655
 656        if (sensor_cpu_power == NULL && !strcmp(sr->name, "cpu-power")) {
 657                if (wf_get_sensor(sr) == 0)
 658                        sensor_cpu_power = sr;
 659        }
 660
 661        if (sensor_cpu_temp == NULL && !strcmp(sr->name, "cpu-temp")) {
 662                if (wf_get_sensor(sr) == 0)
 663                        sensor_cpu_temp = sr;
 664        }
 665
 666        if (sensor_hd_temp == NULL && !strcmp(sr->name, "hd-temp")) {
 667                if (wf_get_sensor(sr) == 0)
 668                        sensor_hd_temp = sr;
 669        }
 670
 671        if (sensor_cpu_power && sensor_cpu_temp && sensor_hd_temp)
 672                wf_smu_all_sensors_ok = 1;
 673}
 674
 675
 676static int wf_smu_notify(struct notifier_block *self,
 677                               unsigned long event, void *data)
 678{
 679        switch(event) {
 680        case WF_EVENT_NEW_CONTROL:
 681                DBG("wf: new control %s detected\n",
 682                    ((struct wf_control *)data)->name);
 683                wf_smu_new_control(data);
 684                wf_smu_readjust = 1;
 685                break;
 686        case WF_EVENT_NEW_SENSOR:
 687                DBG("wf: new sensor %s detected\n",
 688                    ((struct wf_sensor *)data)->name);
 689                wf_smu_new_sensor(data);
 690                break;
 691        case WF_EVENT_TICK:
 692                if (wf_smu_all_controls_ok && wf_smu_all_sensors_ok)
 693                        wf_smu_tick();
 694        }
 695
 696        return 0;
 697}
 698
 699static struct notifier_block wf_smu_events = {
 700        .notifier_call  = wf_smu_notify,
 701};
 702
 703static int wf_init_pm(void)
 704{
 705        const struct smu_sdbp_header *hdr;
 706
 707        hdr = smu_get_sdb_partition(SMU_SDB_SENSORTREE_ID, NULL);
 708        if (hdr != 0) {
 709                struct smu_sdbp_sensortree *st =
 710                        (struct smu_sdbp_sensortree *)&hdr[1];
 711                wf_smu_mach_model = st->model_id;
 712        }
 713
 714        printk(KERN_INFO "windfarm: Initializing for iMacG5 model ID %d\n",
 715               wf_smu_mach_model);
 716
 717        return 0;
 718}
 719
 720static int wf_smu_probe(struct platform_device *ddev)
 721{
 722        wf_register_client(&wf_smu_events);
 723
 724        return 0;
 725}
 726
 727static int wf_smu_remove(struct platform_device *ddev)
 728{
 729        wf_unregister_client(&wf_smu_events);
 730
 731        /* XXX We don't have yet a guarantee that our callback isn't
 732         * in progress when returning from wf_unregister_client, so
 733         * we add an arbitrary delay. I'll have to fix that in the core
 734         */
 735        msleep(1000);
 736
 737        /* Release all sensors */
 738        /* One more crappy race: I don't think we have any guarantee here
 739         * that the attribute callback won't race with the sensor beeing
 740         * disposed of, and I'm not 100% certain what best way to deal
 741         * with that except by adding locks all over... I'll do that
 742         * eventually but heh, who ever rmmod this module anyway ?
 743         */
 744        if (sensor_cpu_power)
 745                wf_put_sensor(sensor_cpu_power);
 746        if (sensor_cpu_temp)
 747                wf_put_sensor(sensor_cpu_temp);
 748        if (sensor_hd_temp)
 749                wf_put_sensor(sensor_hd_temp);
 750
 751        /* Release all controls */
 752        if (fan_cpu_main)
 753                wf_put_control(fan_cpu_main);
 754        if (fan_hd)
 755                wf_put_control(fan_hd);
 756        if (fan_system)
 757                wf_put_control(fan_system);
 758        if (cpufreq_clamp)
 759                wf_put_control(cpufreq_clamp);
 760
 761        /* Destroy control loops state structures */
 762        kfree(wf_smu_sys_fans);
 763        kfree(wf_smu_cpu_fans);
 764
 765        return 0;
 766}
 767
 768static struct platform_driver wf_smu_driver = {
 769        .probe = wf_smu_probe,
 770        .remove = wf_smu_remove,
 771        .driver = {
 772                .name = "windfarm",
 773        },
 774};
 775
 776
 777static int __init wf_smu_init(void)
 778{
 779        int rc = -ENODEV;
 780
 781        if (of_machine_is_compatible("PowerMac8,1") ||
 782            of_machine_is_compatible("PowerMac8,2"))
 783                rc = wf_init_pm();
 784
 785        if (rc == 0) {
 786#ifdef MODULE
 787                request_module("windfarm_smu_controls");
 788                request_module("windfarm_smu_sensors");
 789                request_module("windfarm_lm75_sensor");
 790                request_module("windfarm_cpufreq_clamp");
 791
 792#endif /* MODULE */
 793                platform_driver_register(&wf_smu_driver);
 794        }
 795
 796        return rc;
 797}
 798
 799static void __exit wf_smu_exit(void)
 800{
 801
 802        platform_driver_unregister(&wf_smu_driver);
 803}
 804
 805
 806module_init(wf_smu_init);
 807module_exit(wf_smu_exit);
 808
 809MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 810MODULE_DESCRIPTION("Thermal control logic for iMac G5");
 811MODULE_LICENSE("GPL");
 812MODULE_ALIAS("platform:windfarm");
 813