git.oblomov.eu Git - linux-2.6/blob - drivers/macintosh/therm_pm72.c

   1 /*
   2  * Device driver for the thermostats & fan controller of  the
   3  * Apple G5 "PowerMac7,2" desktop machines.
   4  *
   5  * (c) Copyright IBM Corp. 2003-2004
   6  *
   7  * Maintained by: Benjamin Herrenschmidt
   8  *                <benh@kernel.crashing.org>
   9  *
  10  *
  11  * The algorithm used is the PID control algorithm, used the same
  12  * way the published Darwin code does, using the same values that
  13  * are present in the Darwin 7.0 snapshot property lists.
  14  *
  15  * As far as the CPUs control loops are concerned, I use the
  16  * calibration & PID constants provided by the EEPROM,
  17  * I do _not_ embed any value from the property lists, as the ones
  18  * provided by Darwin 7.0 seem to always have an older version that
  19  * what I've seen on the actual computers.
  20  * It would be interesting to verify that though. Darwin has a
  21  * version code of 1.0.0d11 for all control loops it seems, while
  22  * so far, the machines EEPROMs contain a dataset versioned 1.0.0f
  23  *
  24  * Darwin doesn't provide source to all parts, some missing
  25  * bits like the AppleFCU driver or the actual scale of some
  26  * of the values returned by sensors had to be "guessed" some
  27  * way... or based on what Open Firmware does.
  28  *
  29  * I didn't yet figure out how to get the slots power consumption
  30  * out of the FCU, so that part has not been implemented yet and
  31  * the slots fan is set to a fixed 50% PWM, hoping this value is
  32  * safe enough ...
  33  *
  34  * Note: I have observed strange oscillations of the CPU control
  35  * loop on a dual G5 here. When idle, the CPU exhaust fan tend to
  36  * oscillates slowly (over several minutes) between the minimum
  37  * of 300RPMs and approx. 1000 RPMs. I don't know what is causing
  38  * this, it could be some incorrect constant or an error in the
  39  * way I ported the algorithm, or it could be just normal. I
  40  * don't have full understanding on the way Apple tweaked the PID
  41  * algorithm for the CPU control, it is definitely not a standard
  42  * implementation...
  43  *
  44  * TODO:  - Check MPU structure version/signature
  45  *        - Add things like /sbin/overtemp for non-critical
  46  *          overtemp conditions so userland can take some policy
  47  *          decisions, like slewing down CPUs
  48  *        - Deal with fan and i2c failures in a better way
  49  *        - Maybe do a generic PID based on params used for
  50  *          U3 and Drives ? Definitely need to factor code a bit
  51  *          bettter... also make sensor detection more robust using
  52  *          the device-tree to probe for them
  53  *        - Figure out how to get the slots consumption and set the
  54  *          slots fan accordingly
  55  *
  56  * History:
  57  *
  58  *  Nov. 13, 2003 : 0.5
  59  *      - First release
  60  *
  61  *  Nov. 14, 2003 : 0.6
  62  *      - Read fan speed from FCU, low level fan routines now deal
  63  *        with errors & check fan status, though higher level don't
  64  *        do much.
  65  *      - Move a bunch of definitions to .h file
  66  *
  67  *  Nov. 18, 2003 : 0.7
  68  *      - Fix build on ppc64 kernel
  69  *      - Move back statics definitions to .c file
  70  *      - Avoid calling schedule_timeout with a negative number
  71  *
  72  *  Dec. 18, 2003 : 0.8
  73  *      - Fix typo when reading back fan speed on 2 CPU machines
  74  *
  75  *  Mar. 11, 2004 : 0.9
  76  *      - Rework code accessing the ADC chips, make it more robust and
  77  *        closer to the chip spec. Also make sure it is configured properly,
  78  *        I've seen yet unexplained cases where on startup, I would have stale
  79  *        values in the configuration register
  80  *      - Switch back to use of target fan speed for PID, thus lowering
  81  *        pressure on i2c
  82  *
  83  *  Oct. 20, 2004 : 1.1
  84  *      - Add device-tree lookup for fan IDs, should detect liquid cooling
  85  *        pumps when present
  86  *      - Enable driver for PowerMac7,3 machines
  87  *      - Split the U3/Backside cooling on U3 & U3H versions as Darwin does
  88  *      - Add new CPU cooling algorithm for machines with liquid cooling
  89  *      - Workaround for some PowerMac7,3 with empty "fan" node in the devtree
  90  *      - Fix a signed/unsigned compare issue in some PID loops
  91  *
  92  *  Mar. 10, 2005 : 1.2
  93  *      - Add basic support for Xserve G5
  94  *      - Retreive pumps min/max from EEPROM image in device-tree (broken)
  95  *      - Use min/max macros here or there
  96  *      - Latest darwin updated U3H min fan speed to 20% PWM
  97  *
  98  *  July. 06, 2006 : 1.3
  99  *      - Fix setting of RPM fans on Xserve G5 (they were going too fast)
 100  *      - Add missing slots fan control loop for Xserve G5
 101  *      - Lower fixed slots fan speed from 50% to 40% on desktop G5s. We
 102  *        still can't properly implement the control loop for these, so let's
 103  *        reduce the noise a little bit, it appears that 40% still gives us
 104  *        a pretty good air flow
 105  *      - Add code to "tickle" the FCU regulary so it doesn't think that
 106  *        we are gone while in fact, the machine just didn't need any fan
 107  *        speed change lately
 108  *
 109  */
 110
 111 #include <linux/types.h>
 112 #include <linux/module.h>
 113 #include <linux/errno.h>
 114 #include <linux/kernel.h>
 115 #include <linux/delay.h>
 116 #include <linux/sched.h>
 117 #include <linux/slab.h>
 118 #include <linux/init.h>
 119 #include <linux/spinlock.h>
 120 #include <linux/wait.h>
 121 #include <linux/reboot.h>
 122 #include <linux/kmod.h>
 123 #include <linux/i2c.h>
 124 #include <asm/prom.h>
 125 #include <asm/machdep.h>
 126 #include <asm/io.h>
 127 #include <asm/system.h>
 128 #include <asm/sections.h>
 129 #include <asm/of_device.h>
 130 #include <asm/macio.h>
 131 #include <asm/of_platform.h>
 132
 133 #include "therm_pm72.h"
 134
 135 #define VERSION "1.3"
 136
 137 #undef DEBUG
 138
 139 #ifdef DEBUG
 140 #define DBG(args...)    printk(args)
 141 #else
 142 #define DBG(args...)    do { } while(0)
 143 #endif
 144
 145
 146 /*
 147  * Driver statics
 148  */
 149
 150 static struct of_device *               of_dev;
 151 static struct i2c_adapter *             u3_0;
 152 static struct i2c_adapter *             u3_1;
 153 static struct i2c_adapter *             k2;
 154 static struct i2c_client *              fcu;
 155 static struct cpu_pid_state             cpu_state[2];
 156 static struct basckside_pid_params      backside_params;
 157 static struct backside_pid_state        backside_state;
 158 static struct drives_pid_state          drives_state;
 159 static struct dimm_pid_state            dimms_state;
 160 static struct slots_pid_state           slots_state;
 161 static int                              state;
 162 static int                              cpu_count;
 163 static int                              cpu_pid_type;
 164 static pid_t                            ctrl_task;
 165 static struct completion                ctrl_complete;
 166 static int                              critical_state;
 167 static int                              rackmac;
 168 static s32                              dimm_output_clamp;
 169 static int                              fcu_rpm_shift;
 170 static int                              fcu_tickle_ticks;
 171 static DECLARE_MUTEX(driver_lock);
 172
 173 /*
 174  * We have 3 types of CPU PID control. One is "split" old style control
 175  * for intake & exhaust fans, the other is "combined" control for both
 176  * CPUs that also deals with the pumps when present. To be "compatible"
 177  * with OS X at this point, we only use "COMBINED" on the machines that
 178  * are identified as having the pumps (though that identification is at
 179  * least dodgy). Ultimately, we could probably switch completely to this
 180  * algorithm provided we hack it to deal with the UP case
 181  */
 182 #define CPU_PID_TYPE_SPLIT      0
 183 #define CPU_PID_TYPE_COMBINED   1
 184 #define CPU_PID_TYPE_RACKMAC    2
 185
 186 /*
 187  * This table describes all fans in the FCU. The "id" and "type" values
 188  * are defaults valid for all earlier machines. Newer machines will
 189  * eventually override the table content based on the device-tree
 190  */
 191 struct fcu_fan_table
 192 {
 193         char*   loc;    /* location code */
 194         int     type;   /* 0 = rpm, 1 = pwm, 2 = pump */
 195         int     id;     /* id or -1 */
 196 };
 197
 198 #define FCU_FAN_RPM             0
 199 #define FCU_FAN_PWM             1
 200
 201 #define FCU_FAN_ABSENT_ID       -1
 202
 203 #define FCU_FAN_COUNT           ARRAY_SIZE(fcu_fans)
 204
 205 struct fcu_fan_table    fcu_fans[] = {
 206         [BACKSIDE_FAN_PWM_INDEX] = {
 207                 .loc    = "BACKSIDE,SYS CTRLR FAN",
 208                 .type   = FCU_FAN_PWM,
 209                 .id     = BACKSIDE_FAN_PWM_DEFAULT_ID,
 210         },
 211         [DRIVES_FAN_RPM_INDEX] = {
 212                 .loc    = "DRIVE BAY",
 213                 .type   = FCU_FAN_RPM,
 214                 .id     = DRIVES_FAN_RPM_DEFAULT_ID,
 215         },
 216         [SLOTS_FAN_PWM_INDEX] = {
 217                 .loc    = "SLOT,PCI FAN",
 218                 .type   = FCU_FAN_PWM,
 219                 .id     = SLOTS_FAN_PWM_DEFAULT_ID,
 220         },
 221         [CPUA_INTAKE_FAN_RPM_INDEX] = {
 222                 .loc    = "CPU A INTAKE",
 223                 .type   = FCU_FAN_RPM,
 224                 .id     = CPUA_INTAKE_FAN_RPM_DEFAULT_ID,
 225         },
 226         [CPUA_EXHAUST_FAN_RPM_INDEX] = {
 227                 .loc    = "CPU A EXHAUST",
 228                 .type   = FCU_FAN_RPM,
 229                 .id     = CPUA_EXHAUST_FAN_RPM_DEFAULT_ID,
 230         },
 231         [CPUB_INTAKE_FAN_RPM_INDEX] = {
 232                 .loc    = "CPU B INTAKE",
 233                 .type   = FCU_FAN_RPM,
 234                 .id     = CPUB_INTAKE_FAN_RPM_DEFAULT_ID,
 235         },
 236         [CPUB_EXHAUST_FAN_RPM_INDEX] = {
 237                 .loc    = "CPU B EXHAUST",
 238                 .type   = FCU_FAN_RPM,
 239                 .id     = CPUB_EXHAUST_FAN_RPM_DEFAULT_ID,
 240         },
 241         /* pumps aren't present by default, have to be looked up in the
 242          * device-tree
 243          */
 244         [CPUA_PUMP_RPM_INDEX] = {
 245                 .loc    = "CPU A PUMP",
 246                 .type   = FCU_FAN_RPM,
 247                 .id     = FCU_FAN_ABSENT_ID,
 248         },
 249         [CPUB_PUMP_RPM_INDEX] = {
 250                 .loc    = "CPU B PUMP",
 251                 .type   = FCU_FAN_RPM,
 252                 .id     = FCU_FAN_ABSENT_ID,
 253         },
 254         /* Xserve fans */
 255         [CPU_A1_FAN_RPM_INDEX] = {
 256                 .loc    = "CPU A 1",
 257                 .type   = FCU_FAN_RPM,
 258                 .id     = FCU_FAN_ABSENT_ID,
 259         },
 260         [CPU_A2_FAN_RPM_INDEX] = {
 261                 .loc    = "CPU A 2",
 262                 .type   = FCU_FAN_RPM,
 263                 .id     = FCU_FAN_ABSENT_ID,
 264         },
 265         [CPU_A3_FAN_RPM_INDEX] = {
 266                 .loc    = "CPU A 3",
 267                 .type   = FCU_FAN_RPM,
 268                 .id     = FCU_FAN_ABSENT_ID,
 269         },
 270         [CPU_B1_FAN_RPM_INDEX] = {
 271                 .loc    = "CPU B 1",
 272                 .type   = FCU_FAN_RPM,
 273                 .id     = FCU_FAN_ABSENT_ID,
 274         },
 275         [CPU_B2_FAN_RPM_INDEX] = {
 276                 .loc    = "CPU B 2",
 277                 .type   = FCU_FAN_RPM,
 278                 .id     = FCU_FAN_ABSENT_ID,
 279         },
 280         [CPU_B3_FAN_RPM_INDEX] = {
 281                 .loc    = "CPU B 3",
 282                 .type   = FCU_FAN_RPM,
 283                 .id     = FCU_FAN_ABSENT_ID,
 284         },
 285 };
 286
 287 /*
 288  * i2c_driver structure to attach to the host i2c controller
 289  */
 290
 291 static int therm_pm72_attach(struct i2c_adapter *adapter);
 292 static int therm_pm72_detach(struct i2c_adapter *adapter);
 293
 294 static struct i2c_driver therm_pm72_driver =
 295 {
 296         .driver = {
 297                 .name   = "therm_pm72",
 298         },
 299         .attach_adapter = therm_pm72_attach,
 300         .detach_adapter = therm_pm72_detach,
 301 };
 302
 303 /*
 304  * Utility function to create an i2c_client structure and
 305  * attach it to one of u3 adapters
 306  */
 307 static struct i2c_client *attach_i2c_chip(int id, const char *name)
 308 {
 309         struct i2c_client *clt;
 310         struct i2c_adapter *adap;
 311
 312         if (id & 0x200)
 313                 adap = k2;
 314         else if (id & 0x100)
 315                 adap = u3_1;
 316         else
 317                 adap = u3_0;
 318         if (adap == NULL)
 319                 return NULL;
 320
 321         clt = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 322         if (clt == NULL)
 323                 return NULL;
 324         memset(clt, 0, sizeof(struct i2c_client));
 325
 326         clt->addr = (id >> 1) & 0x7f;
 327         clt->adapter = adap;
 328         clt->driver = &therm_pm72_driver;
 329         strncpy(clt->name, name, I2C_NAME_SIZE-1);
 330
 331         if (i2c_attach_client(clt)) {
 332                 printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
 333                 kfree(clt);
 334                 return NULL;
 335         }
 336         return clt;
 337 }
 338
 339 /*
 340  * Utility function to get rid of the i2c_client structure
 341  * (will also detach from the adapter hopepfully)
 342  */
 343 static void detach_i2c_chip(struct i2c_client *clt)
 344 {
 345         i2c_detach_client(clt);
 346         kfree(clt);
 347 }
 348
 349 /*
 350  * Here are the i2c chip access wrappers
 351  */
 352
 353 static void initialize_adc(struct cpu_pid_state *state)
 354 {
 355         int rc;
 356         u8 buf[2];
 357
 358         /* Read ADC the configuration register and cache it. We
 359          * also make sure Config2 contains proper values, I've seen
 360          * cases where we got stale grabage in there, thus preventing
 361          * proper reading of conv. values
 362          */
 363
 364         /* Clear Config2 */
 365         buf[0] = 5;
 366         buf[1] = 0;
 367         i2c_master_send(state->monitor, buf, 2);
 368
 369         /* Read & cache Config1 */
 370         buf[0] = 1;
 371         rc = i2c_master_send(state->monitor, buf, 1);
 372         if (rc > 0) {
 373                 rc = i2c_master_recv(state->monitor, buf, 1);
 374                 if (rc > 0) {
 375                         state->adc_config = buf[0];
 376                         DBG("ADC config reg: %02x\n", state->adc_config);
 377                         /* Disable shutdown mode */
 378                         state->adc_config &= 0xfe;
 379                         buf[0] = 1;
 380                         buf[1] = state->adc_config;
 381                         rc = i2c_master_send(state->monitor, buf, 2);
 382                 }
 383         }
 384         if (rc <= 0)
 385                 printk(KERN_ERR "therm_pm72: Error reading ADC config"
 386                        " register !\n");
 387 }
 388
 389 static int read_smon_adc(struct cpu_pid_state *state, int chan)
 390 {
 391         int rc, data, tries = 0;
 392         u8 buf[2];
 393
 394         for (;;) {
 395                 /* Set channel */
 396                 buf[0] = 1;
 397                 buf[1] = (state->adc_config & 0x1f) | (chan << 5);
 398                 rc = i2c_master_send(state->monitor, buf, 2);
 399                 if (rc <= 0)
 400                         goto error;
 401                 /* Wait for convertion */
 402                 msleep(1);
 403                 /* Switch to data register */
 404                 buf[0] = 4;
 405                 rc = i2c_master_send(state->monitor, buf, 1);
 406                 if (rc <= 0)
 407                         goto error;
 408                 /* Read result */
 409                 rc = i2c_master_recv(state->monitor, buf, 2);
 410                 if (rc < 0)
 411                         goto error;
 412                 data = ((u16)buf[0]) << 8 | (u16)buf[1];
 413                 return data >> 6;
 414         error:
 415                 DBG("Error reading ADC, retrying...\n");
 416                 if (++tries > 10) {
 417                         printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
 418                         return -1;
 419                 }
 420                 msleep(10);
 421         }
 422 }
 423
 424 static int read_lm87_reg(struct i2c_client * chip, int reg)
 425 {
 426         int rc, tries = 0;
 427         u8 buf;
 428
 429         for (;;) {
 430                 /* Set address */
 431                 buf = (u8)reg;
 432                 rc = i2c_master_send(chip, &buf, 1);
 433                 if (rc <= 0)
 434                         goto error;
 435                 rc = i2c_master_recv(chip, &buf, 1);
 436                 if (rc <= 0)
 437                         goto error;
 438                 return (int)buf;
 439         error:
 440                 DBG("Error reading LM87, retrying...\n");
 441                 if (++tries > 10) {
 442                         printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
 443                         return -1;
 444                 }
 445                 msleep(10);
 446         }
 447 }
 448
 449 static int fan_read_reg(int reg, unsigned char *buf, int nb)
 450 {
 451         int tries, nr, nw;
 452
 453         buf[0] = reg;
 454         tries = 0;
 455         for (;;) {
 456                 nw = i2c_master_send(fcu, buf, 1);
 457                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
 458                         break;
 459                 msleep(10);
 460                 ++tries;
 461         }
 462         if (nw <= 0) {
 463                 printk(KERN_ERR "Failure writing address to FCU: %d", nw);
 464                 return -EIO;
 465         }
 466         tries = 0;
 467         for (;;) {
 468                 nr = i2c_master_recv(fcu, buf, nb);
 469                 if (nr > 0 || (nr < 0 && nr != ENODEV) || tries >= 100)
 470                         break;
 471                 msleep(10);
 472                 ++tries;
 473         }
 474         if (nr <= 0)
 475                 printk(KERN_ERR "Failure reading data from FCU: %d", nw);
 476         return nr;
 477 }
 478
 479 static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
 480 {
 481         int tries, nw;
 482         unsigned char buf[16];
 483
 484         buf[0] = reg;
 485         memcpy(buf+1, ptr, nb);
 486         ++nb;
 487         tries = 0;
 488         for (;;) {
 489                 nw = i2c_master_send(fcu, buf, nb);
 490                 if (nw > 0 || (nw < 0 && nw != EIO) || tries >= 100)
 491                         break;
 492                 msleep(10);
 493                 ++tries;
 494         }
 495         if (nw < 0)
 496                 printk(KERN_ERR "Failure writing to FCU: %d", nw);
 497         return nw;
 498 }
 499
 500 static int start_fcu(void)
 501 {
 502         unsigned char buf = 0xff;
 503         int rc;
 504
 505         rc = fan_write_reg(0xe, &buf, 1);
 506         if (rc < 0)
 507                 return -EIO;
 508         rc = fan_write_reg(0x2e, &buf, 1);
 509         if (rc < 0)
 510                 return -EIO;
 511         rc = fan_read_reg(0, &buf, 1);
 512         if (rc < 0)
 513                 return -EIO;
 514         fcu_rpm_shift = (buf == 1) ? 2 : 3;
 515         printk(KERN_DEBUG "FCU Initialized, RPM fan shift is %d\n",
 516                fcu_rpm_shift);
 517
 518         return 0;
 519 }
 520
 521 static int set_rpm_fan(int fan_index, int rpm)
 522 {
 523         unsigned char buf[2];
 524         int rc, id, min, max;
 525
 526         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 527                 return -EINVAL;
 528         id = fcu_fans[fan_index].id;
 529         if (id == FCU_FAN_ABSENT_ID)
 530                 return -EINVAL;
 531
 532         min = 2400 >> fcu_rpm_shift;
 533         max = 56000 >> fcu_rpm_shift;
 534
 535         if (rpm < min)
 536                 rpm = min;
 537         else if (rpm > max)
 538                 rpm = max;
 539         buf[0] = rpm >> (8 - fcu_rpm_shift);
 540         buf[1] = rpm << fcu_rpm_shift;
 541         rc = fan_write_reg(0x10 + (id * 2), buf, 2);
 542         if (rc < 0)
 543                 return -EIO;
 544         return 0;
 545 }
 546
 547 static int get_rpm_fan(int fan_index, int programmed)
 548 {
 549         unsigned char failure;
 550         unsigned char active;
 551         unsigned char buf[2];
 552         int rc, id, reg_base;
 553
 554         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 555                 return -EINVAL;
 556         id = fcu_fans[fan_index].id;
 557         if (id == FCU_FAN_ABSENT_ID)
 558                 return -EINVAL;
 559
 560         rc = fan_read_reg(0xb, &failure, 1);
 561         if (rc != 1)
 562                 return -EIO;
 563         if ((failure & (1 << id)) != 0)
 564                 return -EFAULT;
 565         rc = fan_read_reg(0xd, &active, 1);
 566         if (rc != 1)
 567                 return -EIO;
 568         if ((active & (1 << id)) == 0)
 569                 return -ENXIO;
 570
 571         /* Programmed value or real current speed */
 572         reg_base = programmed ? 0x10 : 0x11;
 573         rc = fan_read_reg(reg_base + (id * 2), buf, 2);
 574         if (rc != 2)
 575                 return -EIO;
 576
 577         return (buf[0] << (8 - fcu_rpm_shift)) | buf[1] >> fcu_rpm_shift;
 578 }
 579
 580 static int set_pwm_fan(int fan_index, int pwm)
 581 {
 582         unsigned char buf[2];
 583         int rc, id;
 584
 585         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
 586                 return -EINVAL;
 587         id = fcu_fans[fan_index].id;
 588         if (id == FCU_FAN_ABSENT_ID)
 589                 return -EINVAL;
 590
 591         if (pwm < 10)
 592                 pwm = 10;
 593         else if (pwm > 100)
 594                 pwm = 100;
 595         pwm = (pwm * 2559) / 1000;
 596         buf[0] = pwm;
 597         rc = fan_write_reg(0x30 + (id * 2), buf, 1);
 598         if (rc < 0)
 599                 return rc;
 600         return 0;
 601 }
 602
 603 static int get_pwm_fan(int fan_index)
 604 {
 605         unsigned char failure;
 606         unsigned char active;
 607         unsigned char buf[2];
 608         int rc, id;
 609
 610         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
 611                 return -EINVAL;
 612         id = fcu_fans[fan_index].id;
 613         if (id == FCU_FAN_ABSENT_ID)
 614                 return -EINVAL;
 615
 616         rc = fan_read_reg(0x2b, &failure, 1);
 617         if (rc != 1)
 618                 return -EIO;
 619         if ((failure & (1 << id)) != 0)
 620                 return -EFAULT;
 621         rc = fan_read_reg(0x2d, &active, 1);
 622         if (rc != 1)
 623                 return -EIO;
 624         if ((active & (1 << id)) == 0)
 625                 return -ENXIO;
 626
 627         /* Programmed value or real current speed */
 628         rc = fan_read_reg(0x30 + (id * 2), buf, 1);
 629         if (rc != 1)
 630                 return -EIO;
 631
 632         return (buf[0] * 1000) / 2559;
 633 }
 634
 635 static void tickle_fcu(void)
 636 {
 637         int pwm;
 638
 639         pwm = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
 640
 641         DBG("FCU Tickle, slots fan is: %d\n", pwm);
 642         if (pwm < 0)
 643                 pwm = 100;
 644
 645         if (!rackmac) {
 646                 pwm = SLOTS_FAN_DEFAULT_PWM;
 647         } else if (pwm < SLOTS_PID_OUTPUT_MIN)
 648                 pwm = SLOTS_PID_OUTPUT_MIN;
 649
 650         /* That is hopefully enough to make the FCU happy */
 651         set_pwm_fan(SLOTS_FAN_PWM_INDEX, pwm);
 652 }
 653
 654
 655 /*
 656  * Utility routine to read the CPU calibration EEPROM data
 657  * from the device-tree
 658  */
 659 static int read_eeprom(int cpu, struct mpu_data *out)
 660 {
 661         struct device_node *np;
 662         char nodename[64];
 663         const u8 *data;
 664         int len;
 665
 666         /* prom.c routine for finding a node by path is a bit brain dead
 667          * and requires exact @xxx unit numbers. This is a bit ugly but
 668          * will work for these machines
 669          */
 670         sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
 671         np = of_find_node_by_path(nodename);
 672         if (np == NULL) {
 673                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid node from device-tree\n");
 674                 return -ENODEV;
 675         }
 676         data = of_get_property(np, "cpuid", &len);
 677         if (data == NULL) {
 678                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid property from device-tree\n");
 679                 of_node_put(np);
 680                 return -ENODEV;
 681         }
 682         memcpy(out, data, sizeof(struct mpu_data));
 683         of_node_put(np);
 684
 685         return 0;
 686 }
 687
 688 static void fetch_cpu_pumps_minmax(void)
 689 {
 690         struct cpu_pid_state *state0 = &cpu_state[0];
 691         struct cpu_pid_state *state1 = &cpu_state[1];
 692         u16 pump_min = 0, pump_max = 0xffff;
 693         u16 tmp[4];
 694
 695         /* Try to fetch pumps min/max infos from eeprom */
 696
 697         memcpy(&tmp, &state0->mpu.processor_part_num, 8);
 698         if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
 699                 pump_min = max(pump_min, tmp[0]);
 700                 pump_max = min(pump_max, tmp[1]);
 701         }
 702         if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
 703                 pump_min = max(pump_min, tmp[2]);
 704                 pump_max = min(pump_max, tmp[3]);
 705         }
 706
 707         /* Double check the values, this _IS_ needed as the EEPROM on
 708          * some dual 2.5Ghz G5s seem, at least, to have both min & max
 709          * same to the same value ... (grrrr)
 710          */
 711         if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
 712                 pump_min = CPU_PUMP_OUTPUT_MIN;
 713                 pump_max = CPU_PUMP_OUTPUT_MAX;
 714         }
 715
 716         state0->pump_min = state1->pump_min = pump_min;
 717         state0->pump_max = state1->pump_max = pump_max;
 718 }
 719
 720 /*
 721  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 722  * pass around to the attribute functions, so we don't really have
 723  * choice but implement a bunch of them...
 724  *
 725  * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
 726  * the input twice... I accept patches :)
 727  */
 728 #define BUILD_SHOW_FUNC_FIX(name, data)                         \
 729 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 730 {                                                               \
 731         ssize_t r;                                              \
 732         down(&driver_lock);                                     \
 733         r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));        \
 734         up(&driver_lock);                                       \
 735         return r;                                               \
 736 }
 737 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 738 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 739 {                                                               \
 740         return sprintf(buf, "%d", data);                        \
 741 }
 742
 743 BUILD_SHOW_FUNC_FIX(cpu0_temperature, cpu_state[0].last_temp)
 744 BUILD_SHOW_FUNC_FIX(cpu0_voltage, cpu_state[0].voltage)
 745 BUILD_SHOW_FUNC_FIX(cpu0_current, cpu_state[0].current_a)
 746 BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, cpu_state[0].rpm)
 747 BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, cpu_state[0].intake_rpm)
 748
 749 BUILD_SHOW_FUNC_FIX(cpu1_temperature, cpu_state[1].last_temp)
 750 BUILD_SHOW_FUNC_FIX(cpu1_voltage, cpu_state[1].voltage)
 751 BUILD_SHOW_FUNC_FIX(cpu1_current, cpu_state[1].current_a)
 752 BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, cpu_state[1].rpm)
 753 BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, cpu_state[1].intake_rpm)
 754
 755 BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
 756 BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
 757
 758 BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
 759 BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
 760
 761 BUILD_SHOW_FUNC_FIX(slots_temperature, slots_state.last_temp)
 762 BUILD_SHOW_FUNC_INT(slots_fan_pwm, slots_state.pwm)
 763
 764 BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
 765
 766 static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
 767 static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
 768 static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
 769 static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
 770 static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
 771
 772 static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
 773 static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
 774 static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
 775 static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
 776 static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
 777
 778 static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
 779 static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
 780
 781 static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
 782 static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
 783
 784 static DEVICE_ATTR(slots_temperature,S_IRUGO,show_slots_temperature,NULL);
 785 static DEVICE_ATTR(slots_fan_pwm,S_IRUGO,show_slots_fan_pwm,NULL);
 786
 787 static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
 788
 789 /*
 790  * CPUs fans control loop
 791  */
 792
 793 static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
 794 {
 795         s32 ltemp, volts, amps;
 796         int index, rc = 0;
 797
 798         /* Default (in case of error) */
 799         *temp = state->cur_temp;
 800         *power = state->cur_power;
 801
 802         if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
 803                 index = (state->index == 0) ?
 804                         CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
 805         else
 806                 index = (state->index == 0) ?
 807                         CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
 808
 809         /* Read current fan status */
 810         rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
 811         if (rc < 0) {
 812                 /* XXX What do we do now ? Nothing for now, keep old value, but
 813                  * return error upstream
 814                  */
 815                 DBG("  cpu %d, fan reading error !\n", state->index);
 816         } else {
 817                 state->rpm = rc;
 818                 DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
 819         }
 820
 821         /* Get some sensor readings and scale it */
 822         ltemp = read_smon_adc(state, 1);
 823         if (ltemp == -1) {
 824                 /* XXX What do we do now ? */
 825                 state->overtemp++;
 826                 if (rc == 0)
 827                         rc = -EIO;
 828                 DBG("  cpu %d, temp reading error !\n", state->index);
 829         } else {
 830                 /* Fixup temperature according to diode calibration
 831                  */
 832                 DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
 833                     state->index,
 834                     ltemp, state->mpu.mdiode, state->mpu.bdiode);
 835                 *temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
 836                 state->last_temp = *temp;
 837                 DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
 838         }
 839
 840         /*
 841          * Read voltage & current and calculate power
 842          */
 843         volts = read_smon_adc(state, 3);
 844         amps = read_smon_adc(state, 4);
 845
 846         /* Scale voltage and current raw sensor values according to fixed scales
 847          * obtained in Darwin and calculate power from I and V
 848          */
 849         volts *= ADC_CPU_VOLTAGE_SCALE;
 850         amps *= ADC_CPU_CURRENT_SCALE;
 851         *power = (((u64)volts) * ((u64)amps)) >> 16;
 852         state->voltage = volts;
 853         state->current_a = amps;
 854         state->last_power = *power;
 855
 856         DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
 857             state->index, FIX32TOPRINT(state->current_a),
 858             FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
 859
 860         return 0;
 861 }
 862
 863 static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
 864 {
 865         s32 power_target, integral, derivative, proportional, adj_in_target, sval;
 866         s64 integ_p, deriv_p, prop_p, sum;
 867         int i;
 868
 869         /* Calculate power target value (could be done once for all)
 870          * and convert to a 16.16 fp number
 871          */
 872         power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
 873         DBG("  power target: %d.%03d, error: %d.%03d\n",
 874             FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
 875
 876         /* Store temperature and power in history array */
 877         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 878         state->temp_history[state->cur_temp] = temp;
 879         state->cur_power = (state->cur_power + 1) % state->count_power;
 880         state->power_history[state->cur_power] = power;
 881         state->error_history[state->cur_power] = power_target - power;
 882
 883         /* If first loop, fill the history table */
 884         if (state->first) {
 885                 for (i = 0; i < (state->count_power - 1); i++) {
 886                         state->cur_power = (state->cur_power + 1) % state->count_power;
 887                         state->power_history[state->cur_power] = power;
 888                         state->error_history[state->cur_power] = power_target - power;
 889                 }
 890                 for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
 891                         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 892                         state->temp_history[state->cur_temp] = temp;
 893                 }
 894                 state->first = 0;
 895         }
 896
 897         /* Calculate the integral term normally based on the "power" values */
 898         sum = 0;
 899         integral = 0;
 900         for (i = 0; i < state->count_power; i++)
 901                 integral += state->error_history[i];
 902         integral *= CPU_PID_INTERVAL;
 903         DBG("  integral: %08x\n", integral);
 904
 905         /* Calculate the adjusted input (sense value).
 906          *   G_r is 12.20
 907          *   integ is 16.16
 908          *   so the result is 28.36
 909          *
 910          * input target is mpu.ttarget, input max is mpu.tmax
 911          */
 912         integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
 913         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
 914         sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
 915         adj_in_target = (state->mpu.ttarget << 16);
 916         if (adj_in_target > sval)
 917                 adj_in_target = sval;
 918         DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
 919             state->mpu.ttarget);
 920
 921         /* Calculate the derivative term */
 922         derivative = state->temp_history[state->cur_temp] -
 923                 state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
 924                                     % CPU_TEMP_HISTORY_SIZE];
 925         derivative /= CPU_PID_INTERVAL;
 926         deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
 927         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
 928         sum += deriv_p;
 929
 930         /* Calculate the proportional term */
 931         proportional = temp - adj_in_target;
 932         prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
 933         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
 934         sum += prop_p;
 935
 936         /* Scale sum */
 937         sum >>= 36;
 938
 939         DBG("   sum: %d\n", (int)sum);
 940         state->rpm += (s32)sum;
 941 }
 942
 943 static void do_monitor_cpu_combined(void)
 944 {
 945         struct cpu_pid_state *state0 = &cpu_state[0];
 946         struct cpu_pid_state *state1 = &cpu_state[1];
 947         s32 temp0, power0, temp1, power1;
 948         s32 temp_combi, power_combi;
 949         int rc, intake, pump;
 950
 951         rc = do_read_one_cpu_values(state0, &temp0, &power0);
 952         if (rc < 0) {
 953                 /* XXX What do we do now ? */
 954         }
 955         state1->overtemp = 0;
 956         rc = do_read_one_cpu_values(state1, &temp1, &power1);
 957         if (rc < 0) {
 958                 /* XXX What do we do now ? */
 959         }
 960         if (state1->overtemp)
 961                 state0->overtemp++;
 962
 963         temp_combi = max(temp0, temp1);
 964         power_combi = max(power0, power1);
 965
 966         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
 967          * full blown immediately and try to trigger a shutdown
 968          */
 969         if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
 970                 printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
 971                        temp_combi >> 16);
 972                 state0->overtemp += CPU_MAX_OVERTEMP / 4;
 973         } else if (temp_combi > (state0->mpu.tmax << 16))
 974                 state0->overtemp++;
 975         else
 976                 state0->overtemp = 0;
 977         if (state0->overtemp >= CPU_MAX_OVERTEMP)
 978                 critical_state = 1;
 979         if (state0->overtemp > 0) {
 980                 state0->rpm = state0->mpu.rmaxn_exhaust_fan;
 981                 state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
 982                 pump = state0->pump_max;
 983                 goto do_set_fans;
 984         }
 985
 986         /* Do the PID */
 987         do_cpu_pid(state0, temp_combi, power_combi);
 988
 989         /* Range check */
 990         state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
 991         state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
 992
 993         /* Calculate intake fan speed */
 994         intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
 995         intake = max(intake, (int)state0->mpu.rminn_intake_fan);
 996         intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
 997         state0->intake_rpm = intake;
 998
 999         /* Calculate pump speed */
1000         pump = (state0->rpm * state0->pump_max) /
1001                 state0->mpu.rmaxn_exhaust_fan;
1002         pump = min(pump, state0->pump_max);
1003         pump = max(pump, state0->pump_min);
1004
1005  do_set_fans:
1006         /* We copy values from state 0 to state 1 for /sysfs */
1007         state1->rpm = state0->rpm;
1008         state1->intake_rpm = state0->intake_rpm;
1009
1010         DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
1011             state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
1012
1013         /* We should check for errors, shouldn't we ? But then, what
1014          * do we do once the error occurs ? For FCU notified fan
1015          * failures (-EFAULT) we probably want to notify userland
1016          * some way...
1017          */
1018         set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1019         set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1020         set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1021         set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1022
1023         if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1024                 set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
1025         if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1026                 set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
1027 }
1028
1029 static void do_monitor_cpu_split(struct cpu_pid_state *state)
1030 {
1031         s32 temp, power;
1032         int rc, intake;
1033
1034         /* Read current fan status */
1035         rc = do_read_one_cpu_values(state, &temp, &power);
1036         if (rc < 0) {
1037                 /* XXX What do we do now ? */
1038         }
1039
1040         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1041          * full blown immediately and try to trigger a shutdown
1042          */
1043         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1044                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1045                        " (%d) !\n",
1046                        state->index, temp >> 16);
1047                 state->overtemp += CPU_MAX_OVERTEMP / 4;
1048         } else if (temp > (state->mpu.tmax << 16))
1049                 state->overtemp++;
1050         else
1051                 state->overtemp = 0;
1052         if (state->overtemp >= CPU_MAX_OVERTEMP)
1053                 critical_state = 1;
1054         if (state->overtemp > 0) {
1055                 state->rpm = state->mpu.rmaxn_exhaust_fan;
1056                 state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1057                 goto do_set_fans;
1058         }
1059
1060         /* Do the PID */
1061         do_cpu_pid(state, temp, power);
1062
1063         /* Range check */
1064         state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1065         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1066
1067         /* Calculate intake fan */
1068         intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1069         intake = max(intake, (int)state->mpu.rminn_intake_fan);
1070         intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1071         state->intake_rpm = intake;
1072
1073  do_set_fans:
1074         DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1075             state->index, (int)state->rpm, intake, state->overtemp);
1076
1077         /* We should check for errors, shouldn't we ? But then, what
1078          * do we do once the error occurs ? For FCU notified fan
1079          * failures (-EFAULT) we probably want to notify userland
1080          * some way...
1081          */
1082         if (state->index == 0) {
1083                 set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1084                 set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1085         } else {
1086                 set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1087                 set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1088         }
1089 }
1090
1091 static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1092 {
1093         s32 temp, power, fan_min;
1094         int rc;
1095
1096         /* Read current fan status */
1097         rc = do_read_one_cpu_values(state, &temp, &power);
1098         if (rc < 0) {
1099                 /* XXX What do we do now ? */
1100         }
1101
1102         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1103          * full blown immediately and try to trigger a shutdown
1104          */
1105         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1106                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1107                        " (%d) !\n",
1108                        state->index, temp >> 16);
1109                 state->overtemp = CPU_MAX_OVERTEMP / 4;
1110         } else if (temp > (state->mpu.tmax << 16))
1111                 state->overtemp++;
1112         else
1113                 state->overtemp = 0;
1114         if (state->overtemp >= CPU_MAX_OVERTEMP)
1115                 critical_state = 1;
1116         if (state->overtemp > 0) {
1117                 state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1118                 goto do_set_fans;
1119         }
1120
1121         /* Do the PID */
1122         do_cpu_pid(state, temp, power);
1123
1124         /* Check clamp from dimms */
1125         fan_min = dimm_output_clamp;
1126         fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1127
1128         DBG(" CPU min mpu = %d, min dimm = %d\n",
1129             state->mpu.rminn_intake_fan, dimm_output_clamp);
1130
1131         state->rpm = max(state->rpm, (int)fan_min);
1132         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1133         state->intake_rpm = state->rpm;
1134
1135  do_set_fans:
1136         DBG("** CPU %d RPM: %d overtemp: %d\n",
1137             state->index, (int)state->rpm, state->overtemp);
1138
1139         /* We should check for errors, shouldn't we ? But then, what
1140          * do we do once the error occurs ? For FCU notified fan
1141          * failures (-EFAULT) we probably want to notify userland
1142          * some way...
1143          */
1144         if (state->index == 0) {
1145                 set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1146                 set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1147                 set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1148         } else {
1149                 set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1150                 set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1151                 set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1152         }
1153 }
1154
1155 /*
1156  * Initialize the state structure for one CPU control loop
1157  */
1158 static int init_cpu_state(struct cpu_pid_state *state, int index)
1159 {
1160         state->index = index;
1161         state->first = 1;
1162         state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1163         state->overtemp = 0;
1164         state->adc_config = 0x00;
1165
1166
1167         if (index == 0)
1168                 state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1169         else if (index == 1)
1170                 state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1171         if (state->monitor == NULL)
1172                 goto fail;
1173
1174         if (read_eeprom(index, &state->mpu))
1175                 goto fail;
1176
1177         state->count_power = state->mpu.tguardband;
1178         if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1179                 printk(KERN_WARNING "Warning ! too many power history slots\n");
1180                 state->count_power = CPU_POWER_HISTORY_SIZE;
1181         }
1182         DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1183
1184         if (index == 0) {
1185                 device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1186                 device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1187                 device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1188                 device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1189                 device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1190         } else {
1191                 device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1192                 device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1193                 device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1194                 device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1195                 device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1196         }
1197
1198         return 0;
1199  fail:
1200         if (state->monitor)
1201                 detach_i2c_chip(state->monitor);
1202         state->monitor = NULL;
1203
1204         return -ENODEV;
1205 }
1206
1207 /*
1208  * Dispose of the state data for one CPU control loop
1209  */
1210 static void dispose_cpu_state(struct cpu_pid_state *state)
1211 {
1212         if (state->monitor == NULL)
1213                 return;
1214
1215         if (state->index == 0) {
1216                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1217                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1218                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1219                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1220                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1221         } else {
1222                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1223                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1224                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1225                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1226                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1227         }
1228
1229         detach_i2c_chip(state->monitor);
1230         state->monitor = NULL;
1231 }
1232
1233 /*
1234  * Motherboard backside & U3 heatsink fan control loop
1235  */
1236 static void do_monitor_backside(struct backside_pid_state *state)
1237 {
1238         s32 temp, integral, derivative, fan_min;
1239         s64 integ_p, deriv_p, prop_p, sum;
1240         int i, rc;
1241
1242         if (--state->ticks != 0)
1243                 return;
1244         state->ticks = backside_params.interval;
1245
1246         DBG("backside:\n");
1247
1248         /* Check fan status */
1249         rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1250         if (rc < 0) {
1251                 printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1252                 /* XXX What do we do now ? */
1253         } else
1254                 state->pwm = rc;
1255         DBG("  current pwm: %d\n", state->pwm);
1256
1257         /* Get some sensor readings */
1258         temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1259         state->last_temp = temp;
1260         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1261             FIX32TOPRINT(backside_params.input_target));
1262
1263         /* Store temperature and error in history array */
1264         state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1265         state->sample_history[state->cur_sample] = temp;
1266         state->error_history[state->cur_sample] = temp - backside_params.input_target;
1267
1268         /* If first loop, fill the history table */
1269         if (state->first) {
1270                 for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1271                         state->cur_sample = (state->cur_sample + 1) %
1272                                 BACKSIDE_PID_HISTORY_SIZE;
1273                         state->sample_history[state->cur_sample] = temp;
1274                         state->error_history[state->cur_sample] =
1275                                 temp - backside_params.input_target;
1276                 }
1277                 state->first = 0;
1278         }
1279
1280         /* Calculate the integral term */
1281         sum = 0;
1282         integral = 0;
1283         for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1284                 integral += state->error_history[i];
1285         integral *= backside_params.interval;
1286         DBG("  integral: %08x\n", integral);
1287         integ_p = ((s64)backside_params.G_r) * (s64)integral;
1288         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1289         sum += integ_p;
1290
1291         /* Calculate the derivative term */
1292         derivative = state->error_history[state->cur_sample] -
1293                 state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1294                                     % BACKSIDE_PID_HISTORY_SIZE];
1295         derivative /= backside_params.interval;
1296         deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1297         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1298         sum += deriv_p;
1299
1300         /* Calculate the proportional term */
1301         prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1302         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1303         sum += prop_p;
1304
1305         /* Scale sum */
1306         sum >>= 36;
1307
1308         DBG("   sum: %d\n", (int)sum);
1309         if (backside_params.additive)
1310                 state->pwm += (s32)sum;
1311         else
1312                 state->pwm = sum;
1313
1314         /* Check for clamp */
1315         fan_min = (dimm_output_clamp * 100) / 14000;
1316         fan_min = max(fan_min, backside_params.output_min);
1317
1318         state->pwm = max(state->pwm, fan_min);
1319         state->pwm = min(state->pwm, backside_params.output_max);
1320
1321         DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1322         set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1323 }
1324
1325 /*
1326  * Initialize the state structure for the backside fan control loop
1327  */
1328 static int init_backside_state(struct backside_pid_state *state)
1329 {
1330         struct device_node *u3;
1331         int u3h = 1; /* conservative by default */
1332
1333         /*
1334          * There are different PID params for machines with U3 and machines
1335          * with U3H, pick the right ones now
1336          */
1337         u3 = of_find_node_by_path("/u3@0,f8000000");
1338         if (u3 != NULL) {
1339                 const u32 *vers = of_get_property(u3, "device-rev", NULL);
1340                 if (vers)
1341                         if (((*vers) & 0x3f) < 0x34)
1342                                 u3h = 0;
1343                 of_node_put(u3);
1344         }
1345
1346         if (rackmac) {
1347                 backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1348                 backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1349                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1350                 backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1351                 backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1352                 backside_params.G_r = BACKSIDE_PID_G_r;
1353                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1354                 backside_params.additive = 0;
1355         } else if (u3h) {
1356                 backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1357                 backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1358                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1359                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1360                 backside_params.G_p = BACKSIDE_PID_G_p;
1361                 backside_params.G_r = BACKSIDE_PID_G_r;
1362                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1363                 backside_params.additive = 1;
1364         } else {
1365                 backside_params.G_d = BACKSIDE_PID_U3_G_d;
1366                 backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1367                 backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1368                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1369                 backside_params.G_p = BACKSIDE_PID_G_p;
1370                 backside_params.G_r = BACKSIDE_PID_G_r;
1371                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1372                 backside_params.additive = 1;
1373         }
1374
1375         state->ticks = 1;
1376         state->first = 1;
1377         state->pwm = 50;
1378
1379         state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1380         if (state->monitor == NULL)
1381                 return -ENODEV;
1382
1383         device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1384         device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1385
1386         return 0;
1387 }
1388
1389 /*
1390  * Dispose of the state data for the backside control loop
1391  */
1392 static void dispose_backside_state(struct backside_pid_state *state)
1393 {
1394         if (state->monitor == NULL)
1395                 return;
1396
1397         device_remove_file(&of_dev->dev, &dev_attr_backside_temperature);
1398         device_remove_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1399
1400         detach_i2c_chip(state->monitor);
1401         state->monitor = NULL;
1402 }
1403
1404 /*
1405  * Drives bay fan control loop
1406  */
1407 static void do_monitor_drives(struct drives_pid_state *state)
1408 {
1409         s32 temp, integral, derivative;
1410         s64 integ_p, deriv_p, prop_p, sum;
1411         int i, rc;
1412
1413         if (--state->ticks != 0)
1414                 return;
1415         state->ticks = DRIVES_PID_INTERVAL;
1416
1417         DBG("drives:\n");
1418
1419         /* Check fan status */
1420         rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1421         if (rc < 0) {
1422                 printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1423                 /* XXX What do we do now ? */
1424         } else
1425                 state->rpm = rc;
1426         DBG("  current rpm: %d\n", state->rpm);
1427
1428         /* Get some sensor readings */
1429         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1430                                                     DS1775_TEMP)) << 8;
1431         state->last_temp = temp;
1432         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1433             FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1434
1435         /* Store temperature and error in history array */
1436         state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1437         state->sample_history[state->cur_sample] = temp;
1438         state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1439
1440         /* If first loop, fill the history table */
1441         if (state->first) {
1442                 for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1443                         state->cur_sample = (state->cur_sample + 1) %
1444                                 DRIVES_PID_HISTORY_SIZE;
1445                         state->sample_history[state->cur_sample] = temp;
1446                         state->error_history[state->cur_sample] =
1447                                 temp - DRIVES_PID_INPUT_TARGET;
1448                 }
1449                 state->first = 0;
1450         }
1451
1452         /* Calculate the integral term */
1453         sum = 0;
1454         integral = 0;
1455         for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1456                 integral += state->error_history[i];
1457         integral *= DRIVES_PID_INTERVAL;
1458         DBG("  integral: %08x\n", integral);
1459         integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1460         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1461         sum += integ_p;
1462
1463         /* Calculate the derivative term */
1464         derivative = state->error_history[state->cur_sample] -
1465                 state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1466                                     % DRIVES_PID_HISTORY_SIZE];
1467         derivative /= DRIVES_PID_INTERVAL;
1468         deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1469         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1470         sum += deriv_p;
1471
1472         /* Calculate the proportional term */
1473         prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1474         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1475         sum += prop_p;
1476
1477         /* Scale sum */
1478         sum >>= 36;
1479
1480         DBG("   sum: %d\n", (int)sum);
1481         state->rpm += (s32)sum;
1482
1483         state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1484         state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1485
1486         DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1487         set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1488 }
1489
1490 /*
1491  * Initialize the state structure for the drives bay fan control loop
1492  */
1493 static int init_drives_state(struct drives_pid_state *state)
1494 {
1495         state->ticks = 1;
1496         state->first = 1;
1497         state->rpm = 1000;
1498
1499         state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1500         if (state->monitor == NULL)
1501                 return -ENODEV;
1502
1503         device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1504         device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1505
1506         return 0;
1507 }
1508
1509 /*
1510  * Dispose of the state data for the drives control loop
1511  */
1512 static void dispose_drives_state(struct drives_pid_state *state)
1513 {
1514         if (state->monitor == NULL)
1515                 return;
1516
1517         device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1518         device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1519
1520         detach_i2c_chip(state->monitor);
1521         state->monitor = NULL;
1522 }
1523
1524 /*
1525  * DIMMs temp control loop
1526  */
1527 static void do_monitor_dimms(struct dimm_pid_state *state)
1528 {
1529         s32 temp, integral, derivative, fan_min;
1530         s64 integ_p, deriv_p, prop_p, sum;
1531         int i;
1532
1533         if (--state->ticks != 0)
1534                 return;
1535         state->ticks = DIMM_PID_INTERVAL;
1536
1537         DBG("DIMM:\n");
1538
1539         DBG("  current value: %d\n", state->output);
1540
1541         temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1542         if (temp < 0)
1543                 return;
1544         temp <<= 16;
1545         state->last_temp = temp;
1546         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1547             FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1548
1549         /* Store temperature and error in history array */
1550         state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1551         state->sample_history[state->cur_sample] = temp;
1552         state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1553
1554         /* If first loop, fill the history table */
1555         if (state->first) {
1556                 for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1557                         state->cur_sample = (state->cur_sample + 1) %
1558                                 DIMM_PID_HISTORY_SIZE;
1559                         state->sample_history[state->cur_sample] = temp;
1560                         state->error_history[state->cur_sample] =
1561                                 temp - DIMM_PID_INPUT_TARGET;
1562                 }
1563                 state->first = 0;
1564         }
1565
1566         /* Calculate the integral term */
1567         sum = 0;
1568         integral = 0;
1569         for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1570                 integral += state->error_history[i];
1571         integral *= DIMM_PID_INTERVAL;
1572         DBG("  integral: %08x\n", integral);
1573         integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1574         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1575         sum += integ_p;
1576
1577         /* Calculate the derivative term */
1578         derivative = state->error_history[state->cur_sample] -
1579                 state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1580                                     % DIMM_PID_HISTORY_SIZE];
1581         derivative /= DIMM_PID_INTERVAL;
1582         deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1583         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1584         sum += deriv_p;
1585
1586         /* Calculate the proportional term */
1587         prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1588         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1589         sum += prop_p;
1590
1591         /* Scale sum */
1592         sum >>= 36;
1593
1594         DBG("   sum: %d\n", (int)sum);
1595         state->output = (s32)sum;
1596         state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1597         state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1598         dimm_output_clamp = state->output;
1599
1600         DBG("** DIMM clamp value: %d\n", (int)state->output);
1601
1602         /* Backside PID is only every 5 seconds, force backside fan clamping now */
1603         fan_min = (dimm_output_clamp * 100) / 14000;
1604         fan_min = max(fan_min, backside_params.output_min);
1605         if (backside_state.pwm < fan_min) {
1606                 backside_state.pwm = fan_min;
1607                 DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1608                 set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1609         }
1610 }
1611
1612 /*
1613  * Initialize the state structure for the DIMM temp control loop
1614  */
1615 static int init_dimms_state(struct dimm_pid_state *state)
1616 {
1617         state->ticks = 1;
1618         state->first = 1;
1619         state->output = 4000;
1620
1621         state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1622         if (state->monitor == NULL)
1623                 return -ENODEV;
1624
1625         device_create_file(&of_dev->dev, &dev_attr_dimms_temperature);
1626
1627         return 0;
1628 }
1629
1630 /*
1631  * Dispose of the state data for the DIMM control loop
1632  */
1633 static void dispose_dimms_state(struct dimm_pid_state *state)
1634 {
1635         if (state->monitor == NULL)
1636                 return;
1637
1638         device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1639
1640         detach_i2c_chip(state->monitor);
1641         state->monitor = NULL;
1642 }
1643
1644 /*
1645  * Slots fan control loop
1646  */
1647 static void do_monitor_slots(struct slots_pid_state *state)
1648 {
1649         s32 temp, integral, derivative;
1650         s64 integ_p, deriv_p, prop_p, sum;
1651         int i, rc;
1652
1653         if (--state->ticks != 0)
1654                 return;
1655         state->ticks = SLOTS_PID_INTERVAL;
1656
1657         DBG("slots:\n");
1658
1659         /* Check fan status */
1660         rc = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
1661         if (rc < 0) {
1662                 printk(KERN_WARNING "Error %d reading slots fan !\n", rc);
1663                 /* XXX What do we do now ? */
1664         } else
1665                 state->pwm = rc;
1666         DBG("  current pwm: %d\n", state->pwm);
1667
1668         /* Get some sensor readings */
1669         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1670                                                     DS1775_TEMP)) << 8;
1671         state->last_temp = temp;
1672         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1673             FIX32TOPRINT(SLOTS_PID_INPUT_TARGET));
1674
1675         /* Store temperature and error in history array */
1676         state->cur_sample = (state->cur_sample + 1) % SLOTS_PID_HISTORY_SIZE;
1677         state->sample_history[state->cur_sample] = temp;
1678         state->error_history[state->cur_sample] = temp - SLOTS_PID_INPUT_TARGET;
1679
1680         /* If first loop, fill the history table */
1681         if (state->first) {
1682                 for (i = 0; i < (SLOTS_PID_HISTORY_SIZE - 1); i++) {
1683                         state->cur_sample = (state->cur_sample + 1) %
1684                                 SLOTS_PID_HISTORY_SIZE;
1685                         state->sample_history[state->cur_sample] = temp;
1686                         state->error_history[state->cur_sample] =
1687                                 temp - SLOTS_PID_INPUT_TARGET;
1688                 }
1689                 state->first = 0;
1690         }
1691
1692         /* Calculate the integral term */
1693         sum = 0;
1694         integral = 0;
1695         for (i = 0; i < SLOTS_PID_HISTORY_SIZE; i++)
1696                 integral += state->error_history[i];
1697         integral *= SLOTS_PID_INTERVAL;
1698         DBG("  integral: %08x\n", integral);
1699         integ_p = ((s64)SLOTS_PID_G_r) * (s64)integral;
1700         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1701         sum += integ_p;
1702
1703         /* Calculate the derivative term */
1704         derivative = state->error_history[state->cur_sample] -
1705                 state->error_history[(state->cur_sample + SLOTS_PID_HISTORY_SIZE - 1)
1706                                     % SLOTS_PID_HISTORY_SIZE];
1707         derivative /= SLOTS_PID_INTERVAL;
1708         deriv_p = ((s64)SLOTS_PID_G_d) * (s64)derivative;
1709         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1710         sum += deriv_p;
1711
1712         /* Calculate the proportional term */
1713         prop_p = ((s64)SLOTS_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1714         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1715         sum += prop_p;
1716
1717         /* Scale sum */
1718         sum >>= 36;
1719
1720         DBG("   sum: %d\n", (int)sum);
1721         state->pwm = (s32)sum;
1722
1723         state->pwm = max(state->pwm, SLOTS_PID_OUTPUT_MIN);
1724         state->pwm = min(state->pwm, SLOTS_PID_OUTPUT_MAX);
1725
1726         DBG("** DRIVES PWM: %d\n", (int)state->pwm);
1727         set_pwm_fan(SLOTS_FAN_PWM_INDEX, state->pwm);
1728 }
1729
1730 /*
1731  * Initialize the state structure for the slots bay fan control loop
1732  */
1733 static int init_slots_state(struct slots_pid_state *state)
1734 {
1735         state->ticks = 1;
1736         state->first = 1;
1737         state->pwm = 50;
1738
1739         state->monitor = attach_i2c_chip(XSERVE_SLOTS_LM75, "slots_temp");
1740         if (state->monitor == NULL)
1741                 return -ENODEV;
1742
1743         device_create_file(&of_dev->dev, &dev_attr_slots_temperature);
1744         device_create_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1745
1746         return 0;
1747 }
1748
1749 /*
1750  * Dispose of the state data for the slots control loop
1751  */
1752 static void dispose_slots_state(struct slots_pid_state *state)
1753 {
1754         if (state->monitor == NULL)
1755                 return;
1756
1757         device_remove_file(&of_dev->dev, &dev_attr_slots_temperature);
1758         device_remove_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1759
1760         detach_i2c_chip(state->monitor);
1761         state->monitor = NULL;
1762 }
1763
1764
1765 static int call_critical_overtemp(void)
1766 {
1767         char *argv[] = { critical_overtemp_path, NULL };
1768         static char *envp[] = { "HOME=/",
1769                                 "TERM=linux",
1770                                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1771                                 NULL };
1772
1773         return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
1774 }
1775
1776
1777 /*
1778  * Here's the kernel thread that calls the various control loops
1779  */
1780 static int main_control_loop(void *x)
1781 {
1782         daemonize("kfand");
1783
1784         DBG("main_control_loop started\n");
1785
1786         down(&driver_lock);
1787
1788         if (start_fcu() < 0) {
1789                 printk(KERN_ERR "kfand: failed to start FCU\n");
1790                 up(&driver_lock);
1791                 goto out;
1792         }
1793
1794         /* Set the PCI fan once for now on non-RackMac */
1795         if (!rackmac)
1796                 set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1797
1798         /* Initialize ADCs */
1799         initialize_adc(&cpu_state[0]);
1800         if (cpu_state[1].monitor != NULL)
1801                 initialize_adc(&cpu_state[1]);
1802
1803         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1804
1805         up(&driver_lock);
1806
1807         while (state == state_attached) {
1808                 unsigned long elapsed, start;
1809
1810                 start = jiffies;
1811
1812                 down(&driver_lock);
1813
1814                 /* Tickle the FCU just in case */
1815                 if (--fcu_tickle_ticks < 0) {
1816                         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1817                         tickle_fcu();
1818                 }
1819
1820                 /* First, we always calculate the new DIMMs state on an Xserve */
1821                 if (rackmac)
1822                         do_monitor_dimms(&dimms_state);
1823
1824                 /* Then, the CPUs */
1825                 if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1826                         do_monitor_cpu_combined();
1827                 else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1828                         do_monitor_cpu_rack(&cpu_state[0]);
1829                         if (cpu_state[1].monitor != NULL)
1830                                 do_monitor_cpu_rack(&cpu_state[1]);
1831                         // better deal with UP
1832                 } else {
1833                         do_monitor_cpu_split(&cpu_state[0]);
1834                         if (cpu_state[1].monitor != NULL)
1835                                 do_monitor_cpu_split(&cpu_state[1]);
1836                         // better deal with UP
1837                 }
1838                 /* Then, the rest */
1839                 do_monitor_backside(&backside_state);
1840                 if (rackmac)
1841                         do_monitor_slots(&slots_state);
1842                 else
1843                         do_monitor_drives(&drives_state);
1844                 up(&driver_lock);
1845
1846                 if (critical_state == 1) {
1847                         printk(KERN_WARNING "Temperature control detected a critical condition\n");
1848                         printk(KERN_WARNING "Attempting to shut down...\n");
1849                         if (call_critical_overtemp()) {
1850                                 printk(KERN_WARNING "Can't call %s, power off now!\n",
1851                                        critical_overtemp_path);
1852                                 machine_power_off();
1853                         }
1854                 }
1855                 if (critical_state > 0)
1856                         critical_state++;
1857                 if (critical_state > MAX_CRITICAL_STATE) {
1858                         printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1859                         machine_power_off();
1860                 }
1861
1862                 // FIXME: Deal with signals
1863                 elapsed = jiffies - start;
1864                 if (elapsed < HZ)
1865                         schedule_timeout_interruptible(HZ - elapsed);
1866         }
1867
1868  out:
1869         DBG("main_control_loop ended\n");
1870
1871         ctrl_task = 0;
1872         complete_and_exit(&ctrl_complete, 0);
1873 }
1874
1875 /*
1876  * Dispose the control loops when tearing down
1877  */
1878 static void dispose_control_loops(void)
1879 {
1880         dispose_cpu_state(&cpu_state[0]);
1881         dispose_cpu_state(&cpu_state[1]);
1882         dispose_backside_state(&backside_state);
1883         dispose_drives_state(&drives_state);
1884         dispose_slots_state(&slots_state);
1885         dispose_dimms_state(&dimms_state);
1886 }
1887
1888 /*
1889  * Create the control loops. U3-0 i2c bus is up, so we can now
1890  * get to the various sensors
1891  */
1892 static int create_control_loops(void)
1893 {
1894         struct device_node *np;
1895
1896         /* Count CPUs from the device-tree, we don't care how many are
1897          * actually used by Linux
1898          */
1899         cpu_count = 0;
1900         for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1901                 cpu_count++;
1902
1903         DBG("counted %d CPUs in the device-tree\n", cpu_count);
1904
1905         /* Decide the type of PID algorithm to use based on the presence of
1906          * the pumps, though that may not be the best way, that is good enough
1907          * for now
1908          */
1909         if (rackmac)
1910                 cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1911         else if (machine_is_compatible("PowerMac7,3")
1912             && (cpu_count > 1)
1913             && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1914             && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1915                 printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1916                 cpu_pid_type = CPU_PID_TYPE_COMBINED;
1917         } else
1918                 cpu_pid_type = CPU_PID_TYPE_SPLIT;
1919
1920         /* Create control loops for everything. If any fail, everything
1921          * fails
1922          */
1923         if (init_cpu_state(&cpu_state[0], 0))
1924                 goto fail;
1925         if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1926                 fetch_cpu_pumps_minmax();
1927
1928         if (cpu_count > 1 && init_cpu_state(&cpu_state[1], 1))
1929                 goto fail;
1930         if (init_backside_state(&backside_state))
1931                 goto fail;
1932         if (rackmac && init_dimms_state(&dimms_state))
1933                 goto fail;
1934         if (rackmac && init_slots_state(&slots_state))
1935                 goto fail;
1936         if (!rackmac && init_drives_state(&drives_state))
1937                 goto fail;
1938
1939         DBG("all control loops up !\n");
1940
1941         return 0;
1942
1943  fail:
1944         DBG("failure creating control loops, disposing\n");
1945
1946         dispose_control_loops();
1947
1948         return -ENODEV;
1949 }
1950
1951 /*
1952  * Start the control loops after everything is up, that is create
1953  * the thread that will make them run
1954  */
1955 static void start_control_loops(void)
1956 {
1957         init_completion(&ctrl_complete);
1958
1959         ctrl_task = kernel_thread(main_control_loop, NULL, SIGCHLD | CLONE_KERNEL);
1960 }
1961
1962 /*
1963  * Stop the control loops when tearing down
1964  */
1965 static void stop_control_loops(void)
1966 {
1967         if (ctrl_task != 0)
1968                 wait_for_completion(&ctrl_complete);
1969 }
1970
1971 /*
1972  * Attach to the i2c FCU after detecting U3-1 bus
1973  */
1974 static int attach_fcu(void)
1975 {
1976         fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1977         if (fcu == NULL)
1978                 return -ENODEV;
1979
1980         DBG("FCU attached\n");
1981
1982         return 0;
1983 }
1984
1985 /*
1986  * Detach from the i2c FCU when tearing down
1987  */
1988 static void detach_fcu(void)
1989 {
1990         if (fcu)
1991                 detach_i2c_chip(fcu);
1992         fcu = NULL;
1993 }
1994
1995 /*
1996  * Attach to the i2c controller. We probe the various chips based
1997  * on the device-tree nodes and build everything for the driver to
1998  * run, we then kick the driver monitoring thread
1999  */
2000 static int therm_pm72_attach(struct i2c_adapter *adapter)
2001 {
2002         down(&driver_lock);
2003
2004         /* Check state */
2005         if (state == state_detached)
2006                 state = state_attaching;
2007         if (state != state_attaching) {
2008                 up(&driver_lock);
2009                 return 0;
2010         }
2011
2012         /* Check if we are looking for one of these */
2013         if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
2014                 u3_0 = adapter;
2015                 DBG("found U3-0\n");
2016                 if (k2 || !rackmac)
2017                         if (create_control_loops())
2018                                 u3_0 = NULL;
2019         } else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
2020                 u3_1 = adapter;
2021                 DBG("found U3-1, attaching FCU\n");
2022                 if (attach_fcu())
2023                         u3_1 = NULL;
2024         } else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
2025                 k2 = adapter;
2026                 DBG("Found K2\n");
2027                 if (u3_0 && rackmac)
2028                         if (create_control_loops())
2029                                 k2 = NULL;
2030         }
2031         /* We got all we need, start control loops */
2032         if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
2033                 DBG("everything up, starting control loops\n");
2034                 state = state_attached;
2035                 start_control_loops();
2036         }
2037         up(&driver_lock);
2038
2039         return 0;
2040 }
2041
2042 /*
2043  * Called on every adapter when the driver or the i2c controller
2044  * is going away.
2045  */
2046 static int therm_pm72_detach(struct i2c_adapter *adapter)
2047 {
2048         down(&driver_lock);
2049
2050         if (state != state_detached)
2051                 state = state_detaching;
2052
2053         /* Stop control loops if any */
2054         DBG("stopping control loops\n");
2055         up(&driver_lock);
2056         stop_control_loops();
2057         down(&driver_lock);
2058
2059         if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
2060                 DBG("lost U3-0, disposing control loops\n");
2061                 dispose_control_loops();
2062                 u3_0 = NULL;
2063         }
2064
2065         if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
2066                 DBG("lost U3-1, detaching FCU\n");
2067                 detach_fcu();
2068                 u3_1 = NULL;
2069         }
2070         if (u3_0 == NULL && u3_1 == NULL)
2071                 state = state_detached;
2072
2073         up(&driver_lock);
2074
2075         return 0;
2076 }
2077
2078 static int fan_check_loc_match(const char *loc, int fan)
2079 {
2080         char    tmp[64];
2081         char    *c, *e;
2082
2083         strlcpy(tmp, fcu_fans[fan].loc, 64);
2084
2085         c = tmp;
2086         for (;;) {
2087                 e = strchr(c, ',');
2088                 if (e)
2089                         *e = 0;
2090                 if (strcmp(loc, c) == 0)
2091                         return 1;
2092                 if (e == NULL)
2093                         break;
2094                 c = e + 1;
2095         }
2096         return 0;
2097 }
2098
2099 static void fcu_lookup_fans(struct device_node *fcu_node)
2100 {
2101         struct device_node *np = NULL;
2102         int i;
2103
2104         /* The table is filled by default with values that are suitable
2105          * for the old machines without device-tree informations. We scan
2106          * the device-tree and override those values with whatever is
2107          * there
2108          */
2109
2110         DBG("Looking up FCU controls in device-tree...\n");
2111
2112         while ((np = of_get_next_child(fcu_node, np)) != NULL) {
2113                 int type = -1;
2114                 const char *loc;
2115                 const u32 *reg;
2116
2117                 DBG(" control: %s, type: %s\n", np->name, np->type);
2118
2119                 /* Detect control type */
2120                 if (!strcmp(np->type, "fan-rpm-control") ||
2121                     !strcmp(np->type, "fan-rpm"))
2122                         type = FCU_FAN_RPM;
2123                 if (!strcmp(np->type, "fan-pwm-control") ||
2124                     !strcmp(np->type, "fan-pwm"))
2125                         type = FCU_FAN_PWM;
2126                 /* Only care about fans for now */
2127                 if (type == -1)
2128                         continue;
2129
2130                 /* Lookup for a matching location */
2131                 loc = of_get_property(np, "location", NULL);
2132                 reg = of_get_property(np, "reg", NULL);
2133                 if (loc == NULL || reg == NULL)
2134                         continue;
2135                 DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
2136
2137                 for (i = 0; i < FCU_FAN_COUNT; i++) {
2138                         int fan_id;
2139
2140                         if (!fan_check_loc_match(loc, i))
2141                                 continue;
2142                         DBG(" location match, index: %d\n", i);
2143                         fcu_fans[i].id = FCU_FAN_ABSENT_ID;
2144                         if (type != fcu_fans[i].type) {
2145                                 printk(KERN_WARNING "therm_pm72: Fan type mismatch "
2146                                        "in device-tree for %s\n", np->full_name);
2147                                 break;
2148                         }
2149                         if (type == FCU_FAN_RPM)
2150                                 fan_id = ((*reg) - 0x10) / 2;
2151                         else
2152                                 fan_id = ((*reg) - 0x30) / 2;
2153                         if (fan_id > 7) {
2154                                 printk(KERN_WARNING "therm_pm72: Can't parse "
2155                                        "fan ID in device-tree for %s\n", np->full_name);
2156                                 break;
2157                         }
2158                         DBG(" fan id -> %d, type -> %d\n", fan_id, type);
2159                         fcu_fans[i].id = fan_id;
2160                 }
2161         }
2162
2163         /* Now dump the array */
2164         printk(KERN_INFO "Detected fan controls:\n");
2165         for (i = 0; i < FCU_FAN_COUNT; i++) {
2166                 if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
2167                         continue;
2168                 printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
2169                        fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
2170                        fcu_fans[i].id, fcu_fans[i].loc);
2171         }
2172 }
2173
2174 static int fcu_of_probe(struct of_device* dev, const struct of_device_id *match)
2175 {
2176         state = state_detached;
2177
2178         /* Lookup the fans in the device tree */
2179         fcu_lookup_fans(dev->node);
2180
2181         /* Add the driver */
2182         return i2c_add_driver(&therm_pm72_driver);
2183 }
2184
2185 static int fcu_of_remove(struct of_device* dev)
2186 {
2187         i2c_del_driver(&therm_pm72_driver);
2188
2189         return 0;
2190 }
2191
2192 static struct of_device_id fcu_match[] =
2193 {
2194         {
2195         .type           = "fcu",
2196         },
2197         {},
2198 };
2199
2200 static struct of_platform_driver fcu_of_platform_driver =
2201 {
2202         .name           = "temperature",
2203         .match_table    = fcu_match,
2204         .probe          = fcu_of_probe,
2205         .remove         = fcu_of_remove
2206 };
2207
2208 /*
2209  * Check machine type, attach to i2c controller
2210  */
2211 static int __init therm_pm72_init(void)
2212 {
2213         struct device_node *np;
2214
2215         rackmac = machine_is_compatible("RackMac3,1");
2216
2217         if (!machine_is_compatible("PowerMac7,2") &&
2218             !machine_is_compatible("PowerMac7,3") &&
2219             !rackmac)
2220                 return -ENODEV;
2221
2222         printk(KERN_INFO "PowerMac G5 Thermal control driver %s\n", VERSION);
2223
2224         np = of_find_node_by_type(NULL, "fcu");
2225         if (np == NULL) {
2226                 /* Some machines have strangely broken device-tree */
2227                 np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
2228                 if (np == NULL) {
2229                             printk(KERN_ERR "Can't find FCU in device-tree !\n");
2230                             return -ENODEV;
2231                 }
2232         }
2233         of_dev = of_platform_device_create(np, "temperature", NULL);
2234         if (of_dev == NULL) {
2235                 printk(KERN_ERR "Can't register FCU platform device !\n");
2236                 return -ENODEV;
2237         }
2238
2239         of_register_platform_driver(&fcu_of_platform_driver);
2240
2241         return 0;
2242 }
2243
2244 static void __exit therm_pm72_exit(void)
2245 {
2246         of_unregister_platform_driver(&fcu_of_platform_driver);
2247
2248         if (of_dev)
2249                 of_device_unregister(of_dev);
2250 }
2251
2252 module_init(therm_pm72_init);
2253 module_exit(therm_pm72_exit);
2254
2255 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
2256 MODULE_DESCRIPTION("Driver for Apple's PowerMac G5 thermal control");
2257 MODULE_LICENSE("GPL");
2258