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 <linux/kthread.h>
 125 #include <linux/mutex.h>
 126 #include <asm/prom.h>
 127 #include <asm/machdep.h>
 128 #include <asm/io.h>
 129 #include <asm/system.h>
 130 #include <asm/sections.h>
 131 #include <asm/of_device.h>
 132 #include <asm/macio.h>
 133 #include <asm/of_platform.h>
 134
 135 #include "therm_pm72.h"
 136
 137 #define VERSION "1.3"
 138
 139 #undef DEBUG
 140
 141 #ifdef DEBUG
 142 #define DBG(args...)    printk(args)
 143 #else
 144 #define DBG(args...)    do { } while(0)
 145 #endif
 146
 147
 148 /*
 149  * Driver statics
 150  */
 151
 152 static struct of_device *               of_dev;
 153 static struct i2c_adapter *             u3_0;
 154 static struct i2c_adapter *             u3_1;
 155 static struct i2c_adapter *             k2;
 156 static struct i2c_client *              fcu;
 157 static struct cpu_pid_state             cpu_state[2];
 158 static struct basckside_pid_params      backside_params;
 159 static struct backside_pid_state        backside_state;
 160 static struct drives_pid_state          drives_state;
 161 static struct dimm_pid_state            dimms_state;
 162 static struct slots_pid_state           slots_state;
 163 static int                              state;
 164 static int                              cpu_count;
 165 static int                              cpu_pid_type;
 166 static struct task_struct               *ctrl_task;
 167 static struct completion                ctrl_complete;
 168 static int                              critical_state;
 169 static int                              rackmac;
 170 static s32                              dimm_output_clamp;
 171 static int                              fcu_rpm_shift;
 172 static int                              fcu_tickle_ticks;
 173 static DEFINE_MUTEX(driver_lock);
 174
 175 /*
 176  * We have 3 types of CPU PID control. One is "split" old style control
 177  * for intake & exhaust fans, the other is "combined" control for both
 178  * CPUs that also deals with the pumps when present. To be "compatible"
 179  * with OS X at this point, we only use "COMBINED" on the machines that
 180  * are identified as having the pumps (though that identification is at
 181  * least dodgy). Ultimately, we could probably switch completely to this
 182  * algorithm provided we hack it to deal with the UP case
 183  */
 184 #define CPU_PID_TYPE_SPLIT      0
 185 #define CPU_PID_TYPE_COMBINED   1
 186 #define CPU_PID_TYPE_RACKMAC    2
 187
 188 /*
 189  * This table describes all fans in the FCU. The "id" and "type" values
 190  * are defaults valid for all earlier machines. Newer machines will
 191  * eventually override the table content based on the device-tree
 192  */
 193 struct fcu_fan_table
 194 {
 195         char*   loc;    /* location code */
 196         int     type;   /* 0 = rpm, 1 = pwm, 2 = pump */
 197         int     id;     /* id or -1 */
 198 };
 199
 200 #define FCU_FAN_RPM             0
 201 #define FCU_FAN_PWM             1
 202
 203 #define FCU_FAN_ABSENT_ID       -1
 204
 205 #define FCU_FAN_COUNT           ARRAY_SIZE(fcu_fans)
 206
 207 struct fcu_fan_table    fcu_fans[] = {
 208         [BACKSIDE_FAN_PWM_INDEX] = {
 209                 .loc    = "BACKSIDE,SYS CTRLR FAN",
 210                 .type   = FCU_FAN_PWM,
 211                 .id     = BACKSIDE_FAN_PWM_DEFAULT_ID,
 212         },
 213         [DRIVES_FAN_RPM_INDEX] = {
 214                 .loc    = "DRIVE BAY",
 215                 .type   = FCU_FAN_RPM,
 216                 .id     = DRIVES_FAN_RPM_DEFAULT_ID,
 217         },
 218         [SLOTS_FAN_PWM_INDEX] = {
 219                 .loc    = "SLOT,PCI FAN",
 220                 .type   = FCU_FAN_PWM,
 221                 .id     = SLOTS_FAN_PWM_DEFAULT_ID,
 222         },
 223         [CPUA_INTAKE_FAN_RPM_INDEX] = {
 224                 .loc    = "CPU A INTAKE",
 225                 .type   = FCU_FAN_RPM,
 226                 .id     = CPUA_INTAKE_FAN_RPM_DEFAULT_ID,
 227         },
 228         [CPUA_EXHAUST_FAN_RPM_INDEX] = {
 229                 .loc    = "CPU A EXHAUST",
 230                 .type   = FCU_FAN_RPM,
 231                 .id     = CPUA_EXHAUST_FAN_RPM_DEFAULT_ID,
 232         },
 233         [CPUB_INTAKE_FAN_RPM_INDEX] = {
 234                 .loc    = "CPU B INTAKE",
 235                 .type   = FCU_FAN_RPM,
 236                 .id     = CPUB_INTAKE_FAN_RPM_DEFAULT_ID,
 237         },
 238         [CPUB_EXHAUST_FAN_RPM_INDEX] = {
 239                 .loc    = "CPU B EXHAUST",
 240                 .type   = FCU_FAN_RPM,
 241                 .id     = CPUB_EXHAUST_FAN_RPM_DEFAULT_ID,
 242         },
 243         /* pumps aren't present by default, have to be looked up in the
 244          * device-tree
 245          */
 246         [CPUA_PUMP_RPM_INDEX] = {
 247                 .loc    = "CPU A PUMP",
 248                 .type   = FCU_FAN_RPM,
 249                 .id     = FCU_FAN_ABSENT_ID,
 250         },
 251         [CPUB_PUMP_RPM_INDEX] = {
 252                 .loc    = "CPU B PUMP",
 253                 .type   = FCU_FAN_RPM,
 254                 .id     = FCU_FAN_ABSENT_ID,
 255         },
 256         /* Xserve fans */
 257         [CPU_A1_FAN_RPM_INDEX] = {
 258                 .loc    = "CPU A 1",
 259                 .type   = FCU_FAN_RPM,
 260                 .id     = FCU_FAN_ABSENT_ID,
 261         },
 262         [CPU_A2_FAN_RPM_INDEX] = {
 263                 .loc    = "CPU A 2",
 264                 .type   = FCU_FAN_RPM,
 265                 .id     = FCU_FAN_ABSENT_ID,
 266         },
 267         [CPU_A3_FAN_RPM_INDEX] = {
 268                 .loc    = "CPU A 3",
 269                 .type   = FCU_FAN_RPM,
 270                 .id     = FCU_FAN_ABSENT_ID,
 271         },
 272         [CPU_B1_FAN_RPM_INDEX] = {
 273                 .loc    = "CPU B 1",
 274                 .type   = FCU_FAN_RPM,
 275                 .id     = FCU_FAN_ABSENT_ID,
 276         },
 277         [CPU_B2_FAN_RPM_INDEX] = {
 278                 .loc    = "CPU B 2",
 279                 .type   = FCU_FAN_RPM,
 280                 .id     = FCU_FAN_ABSENT_ID,
 281         },
 282         [CPU_B3_FAN_RPM_INDEX] = {
 283                 .loc    = "CPU B 3",
 284                 .type   = FCU_FAN_RPM,
 285                 .id     = FCU_FAN_ABSENT_ID,
 286         },
 287 };
 288
 289 /*
 290  * i2c_driver structure to attach to the host i2c controller
 291  */
 292
 293 static int therm_pm72_attach(struct i2c_adapter *adapter);
 294 static int therm_pm72_detach(struct i2c_adapter *adapter);
 295
 296 static struct i2c_driver therm_pm72_driver =
 297 {
 298         .driver = {
 299                 .name   = "therm_pm72",
 300         },
 301         .attach_adapter = therm_pm72_attach,
 302         .detach_adapter = therm_pm72_detach,
 303 };
 304
 305 /*
 306  * Utility function to create an i2c_client structure and
 307  * attach it to one of u3 adapters
 308  */
 309 static struct i2c_client *attach_i2c_chip(int id, const char *name)
 310 {
 311         struct i2c_client *clt;
 312         struct i2c_adapter *adap;
 313
 314         if (id & 0x200)
 315                 adap = k2;
 316         else if (id & 0x100)
 317                 adap = u3_1;
 318         else
 319                 adap = u3_0;
 320         if (adap == NULL)
 321                 return NULL;
 322
 323         clt = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
 324         if (clt == NULL)
 325                 return NULL;
 326
 327         clt->addr = (id >> 1) & 0x7f;
 328         clt->adapter = adap;
 329         clt->driver = &therm_pm72_driver;
 330         strncpy(clt->name, name, I2C_NAME_SIZE-1);
 331
 332         if (i2c_attach_client(clt)) {
 333                 printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
 334                 kfree(clt);
 335                 return NULL;
 336         }
 337         return clt;
 338 }
 339
 340 /*
 341  * Utility function to get rid of the i2c_client structure
 342  * (will also detach from the adapter hopepfully)
 343  */
 344 static void detach_i2c_chip(struct i2c_client *clt)
 345 {
 346         i2c_detach_client(clt);
 347         kfree(clt);
 348 }
 349
 350 /*
 351  * Here are the i2c chip access wrappers
 352  */
 353
 354 static void initialize_adc(struct cpu_pid_state *state)
 355 {
 356         int rc;
 357         u8 buf[2];
 358
 359         /* Read ADC the configuration register and cache it. We
 360          * also make sure Config2 contains proper values, I've seen
 361          * cases where we got stale grabage in there, thus preventing
 362          * proper reading of conv. values
 363          */
 364
 365         /* Clear Config2 */
 366         buf[0] = 5;
 367         buf[1] = 0;
 368         i2c_master_send(state->monitor, buf, 2);
 369
 370         /* Read & cache Config1 */
 371         buf[0] = 1;
 372         rc = i2c_master_send(state->monitor, buf, 1);
 373         if (rc > 0) {
 374                 rc = i2c_master_recv(state->monitor, buf, 1);
 375                 if (rc > 0) {
 376                         state->adc_config = buf[0];
 377                         DBG("ADC config reg: %02x\n", state->adc_config);
 378                         /* Disable shutdown mode */
 379                         state->adc_config &= 0xfe;
 380                         buf[0] = 1;
 381                         buf[1] = state->adc_config;
 382                         rc = i2c_master_send(state->monitor, buf, 2);
 383                 }
 384         }
 385         if (rc <= 0)
 386                 printk(KERN_ERR "therm_pm72: Error reading ADC config"
 387                        " register !\n");
 388 }
 389
 390 static int read_smon_adc(struct cpu_pid_state *state, int chan)
 391 {
 392         int rc, data, tries = 0;
 393         u8 buf[2];
 394
 395         for (;;) {
 396                 /* Set channel */
 397                 buf[0] = 1;
 398                 buf[1] = (state->adc_config & 0x1f) | (chan << 5);
 399                 rc = i2c_master_send(state->monitor, buf, 2);
 400                 if (rc <= 0)
 401                         goto error;
 402                 /* Wait for convertion */
 403                 msleep(1);
 404                 /* Switch to data register */
 405                 buf[0] = 4;
 406                 rc = i2c_master_send(state->monitor, buf, 1);
 407                 if (rc <= 0)
 408                         goto error;
 409                 /* Read result */
 410                 rc = i2c_master_recv(state->monitor, buf, 2);
 411                 if (rc < 0)
 412                         goto error;
 413                 data = ((u16)buf[0]) << 8 | (u16)buf[1];
 414                 return data >> 6;
 415         error:
 416                 DBG("Error reading ADC, retrying...\n");
 417                 if (++tries > 10) {
 418                         printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
 419                         return -1;
 420                 }
 421                 msleep(10);
 422         }
 423 }
 424
 425 static int read_lm87_reg(struct i2c_client * chip, int reg)
 426 {
 427         int rc, tries = 0;
 428         u8 buf;
 429
 430         for (;;) {
 431                 /* Set address */
 432                 buf = (u8)reg;
 433                 rc = i2c_master_send(chip, &buf, 1);
 434                 if (rc <= 0)
 435                         goto error;
 436                 rc = i2c_master_recv(chip, &buf, 1);
 437                 if (rc <= 0)
 438                         goto error;
 439                 return (int)buf;
 440         error:
 441                 DBG("Error reading LM87, retrying...\n");
 442                 if (++tries > 10) {
 443                         printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
 444                         return -1;
 445                 }
 446                 msleep(10);
 447         }
 448 }
 449
 450 static int fan_read_reg(int reg, unsigned char *buf, int nb)
 451 {
 452         int tries, nr, nw;
 453
 454         buf[0] = reg;
 455         tries = 0;
 456         for (;;) {
 457                 nw = i2c_master_send(fcu, buf, 1);
 458                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
 459                         break;
 460                 msleep(10);
 461                 ++tries;
 462         }
 463         if (nw <= 0) {
 464                 printk(KERN_ERR "Failure writing address to FCU: %d", nw);
 465                 return -EIO;
 466         }
 467         tries = 0;
 468         for (;;) {
 469                 nr = i2c_master_recv(fcu, buf, nb);
 470                 if (nr > 0 || (nr < 0 && nr != ENODEV) || tries >= 100)
 471                         break;
 472                 msleep(10);
 473                 ++tries;
 474         }
 475         if (nr <= 0)
 476                 printk(KERN_ERR "Failure reading data from FCU: %d", nw);
 477         return nr;
 478 }
 479
 480 static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
 481 {
 482         int tries, nw;
 483         unsigned char buf[16];
 484
 485         buf[0] = reg;
 486         memcpy(buf+1, ptr, nb);
 487         ++nb;
 488         tries = 0;
 489         for (;;) {
 490                 nw = i2c_master_send(fcu, buf, nb);
 491                 if (nw > 0 || (nw < 0 && nw != EIO) || tries >= 100)
 492                         break;
 493                 msleep(10);
 494                 ++tries;
 495         }
 496         if (nw < 0)
 497                 printk(KERN_ERR "Failure writing to FCU: %d", nw);
 498         return nw;
 499 }
 500
 501 static int start_fcu(void)
 502 {
 503         unsigned char buf = 0xff;
 504         int rc;
 505
 506         rc = fan_write_reg(0xe, &buf, 1);
 507         if (rc < 0)
 508                 return -EIO;
 509         rc = fan_write_reg(0x2e, &buf, 1);
 510         if (rc < 0)
 511                 return -EIO;
 512         rc = fan_read_reg(0, &buf, 1);
 513         if (rc < 0)
 514                 return -EIO;
 515         fcu_rpm_shift = (buf == 1) ? 2 : 3;
 516         printk(KERN_DEBUG "FCU Initialized, RPM fan shift is %d\n",
 517                fcu_rpm_shift);
 518
 519         return 0;
 520 }
 521
 522 static int set_rpm_fan(int fan_index, int rpm)
 523 {
 524         unsigned char buf[2];
 525         int rc, id, min, max;
 526
 527         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 528                 return -EINVAL;
 529         id = fcu_fans[fan_index].id;
 530         if (id == FCU_FAN_ABSENT_ID)
 531                 return -EINVAL;
 532
 533         min = 2400 >> fcu_rpm_shift;
 534         max = 56000 >> fcu_rpm_shift;
 535
 536         if (rpm < min)
 537                 rpm = min;
 538         else if (rpm > max)
 539                 rpm = max;
 540         buf[0] = rpm >> (8 - fcu_rpm_shift);
 541         buf[1] = rpm << fcu_rpm_shift;
 542         rc = fan_write_reg(0x10 + (id * 2), buf, 2);
 543         if (rc < 0)
 544                 return -EIO;
 545         return 0;
 546 }
 547
 548 static int get_rpm_fan(int fan_index, int programmed)
 549 {
 550         unsigned char failure;
 551         unsigned char active;
 552         unsigned char buf[2];
 553         int rc, id, reg_base;
 554
 555         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 556                 return -EINVAL;
 557         id = fcu_fans[fan_index].id;
 558         if (id == FCU_FAN_ABSENT_ID)
 559                 return -EINVAL;
 560
 561         rc = fan_read_reg(0xb, &failure, 1);
 562         if (rc != 1)
 563                 return -EIO;
 564         if ((failure & (1 << id)) != 0)
 565                 return -EFAULT;
 566         rc = fan_read_reg(0xd, &active, 1);
 567         if (rc != 1)
 568                 return -EIO;
 569         if ((active & (1 << id)) == 0)
 570                 return -ENXIO;
 571
 572         /* Programmed value or real current speed */
 573         reg_base = programmed ? 0x10 : 0x11;
 574         rc = fan_read_reg(reg_base + (id * 2), buf, 2);
 575         if (rc != 2)
 576                 return -EIO;
 577
 578         return (buf[0] << (8 - fcu_rpm_shift)) | buf[1] >> fcu_rpm_shift;
 579 }
 580
 581 static int set_pwm_fan(int fan_index, int pwm)
 582 {
 583         unsigned char buf[2];
 584         int rc, id;
 585
 586         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
 587                 return -EINVAL;
 588         id = fcu_fans[fan_index].id;
 589         if (id == FCU_FAN_ABSENT_ID)
 590                 return -EINVAL;
 591
 592         if (pwm < 10)
 593                 pwm = 10;
 594         else if (pwm > 100)
 595                 pwm = 100;
 596         pwm = (pwm * 2559) / 1000;
 597         buf[0] = pwm;
 598         rc = fan_write_reg(0x30 + (id * 2), buf, 1);
 599         if (rc < 0)
 600                 return rc;
 601         return 0;
 602 }
 603
 604 static int get_pwm_fan(int fan_index)
 605 {
 606         unsigned char failure;
 607         unsigned char active;
 608         unsigned char buf[2];
 609         int rc, id;
 610
 611         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
 612                 return -EINVAL;
 613         id = fcu_fans[fan_index].id;
 614         if (id == FCU_FAN_ABSENT_ID)
 615                 return -EINVAL;
 616
 617         rc = fan_read_reg(0x2b, &failure, 1);
 618         if (rc != 1)
 619                 return -EIO;
 620         if ((failure & (1 << id)) != 0)
 621                 return -EFAULT;
 622         rc = fan_read_reg(0x2d, &active, 1);
 623         if (rc != 1)
 624                 return -EIO;
 625         if ((active & (1 << id)) == 0)
 626                 return -ENXIO;
 627
 628         /* Programmed value or real current speed */
 629         rc = fan_read_reg(0x30 + (id * 2), buf, 1);
 630         if (rc != 1)
 631                 return -EIO;
 632
 633         return (buf[0] * 1000) / 2559;
 634 }
 635
 636 static void tickle_fcu(void)
 637 {
 638         int pwm;
 639
 640         pwm = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
 641
 642         DBG("FCU Tickle, slots fan is: %d\n", pwm);
 643         if (pwm < 0)
 644                 pwm = 100;
 645
 646         if (!rackmac) {
 647                 pwm = SLOTS_FAN_DEFAULT_PWM;
 648         } else if (pwm < SLOTS_PID_OUTPUT_MIN)
 649                 pwm = SLOTS_PID_OUTPUT_MIN;
 650
 651         /* That is hopefully enough to make the FCU happy */
 652         set_pwm_fan(SLOTS_FAN_PWM_INDEX, pwm);
 653 }
 654
 655
 656 /*
 657  * Utility routine to read the CPU calibration EEPROM data
 658  * from the device-tree
 659  */
 660 static int read_eeprom(int cpu, struct mpu_data *out)
 661 {
 662         struct device_node *np;
 663         char nodename[64];
 664         const u8 *data;
 665         int len;
 666
 667         /* prom.c routine for finding a node by path is a bit brain dead
 668          * and requires exact @xxx unit numbers. This is a bit ugly but
 669          * will work for these machines
 670          */
 671         sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
 672         np = of_find_node_by_path(nodename);
 673         if (np == NULL) {
 674                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid node from device-tree\n");
 675                 return -ENODEV;
 676         }
 677         data = of_get_property(np, "cpuid", &len);
 678         if (data == NULL) {
 679                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid property from device-tree\n");
 680                 of_node_put(np);
 681                 return -ENODEV;
 682         }
 683         memcpy(out, data, sizeof(struct mpu_data));
 684         of_node_put(np);
 685
 686         return 0;
 687 }
 688
 689 static void fetch_cpu_pumps_minmax(void)
 690 {
 691         struct cpu_pid_state *state0 = &cpu_state[0];
 692         struct cpu_pid_state *state1 = &cpu_state[1];
 693         u16 pump_min = 0, pump_max = 0xffff;
 694         u16 tmp[4];
 695
 696         /* Try to fetch pumps min/max infos from eeprom */
 697
 698         memcpy(&tmp, &state0->mpu.processor_part_num, 8);
 699         if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
 700                 pump_min = max(pump_min, tmp[0]);
 701                 pump_max = min(pump_max, tmp[1]);
 702         }
 703         if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
 704                 pump_min = max(pump_min, tmp[2]);
 705                 pump_max = min(pump_max, tmp[3]);
 706         }
 707
 708         /* Double check the values, this _IS_ needed as the EEPROM on
 709          * some dual 2.5Ghz G5s seem, at least, to have both min & max
 710          * same to the same value ... (grrrr)
 711          */
 712         if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
 713                 pump_min = CPU_PUMP_OUTPUT_MIN;
 714                 pump_max = CPU_PUMP_OUTPUT_MAX;
 715         }
 716
 717         state0->pump_min = state1->pump_min = pump_min;
 718         state0->pump_max = state1->pump_max = pump_max;
 719 }
 720
 721 /*
 722  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 723  * pass around to the attribute functions, so we don't really have
 724  * choice but implement a bunch of them...
 725  *
 726  * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
 727  * the input twice... I accept patches :)
 728  */
 729 #define BUILD_SHOW_FUNC_FIX(name, data)                         \
 730 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 731 {                                                               \
 732         ssize_t r;                                              \
 733         mutex_lock(&driver_lock);                                       \
 734         r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));        \
 735         mutex_unlock(&driver_lock);                                     \
 736         return r;                                               \
 737 }
 738 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 739 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 740 {                                                               \
 741         return sprintf(buf, "%d", data);                        \
 742 }
 743
 744 BUILD_SHOW_FUNC_FIX(cpu0_temperature, cpu_state[0].last_temp)
 745 BUILD_SHOW_FUNC_FIX(cpu0_voltage, cpu_state[0].voltage)
 746 BUILD_SHOW_FUNC_FIX(cpu0_current, cpu_state[0].current_a)
 747 BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, cpu_state[0].rpm)
 748 BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, cpu_state[0].intake_rpm)
 749
 750 BUILD_SHOW_FUNC_FIX(cpu1_temperature, cpu_state[1].last_temp)
 751 BUILD_SHOW_FUNC_FIX(cpu1_voltage, cpu_state[1].voltage)
 752 BUILD_SHOW_FUNC_FIX(cpu1_current, cpu_state[1].current_a)
 753 BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, cpu_state[1].rpm)
 754 BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, cpu_state[1].intake_rpm)
 755
 756 BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
 757 BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
 758
 759 BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
 760 BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
 761
 762 BUILD_SHOW_FUNC_FIX(slots_temperature, slots_state.last_temp)
 763 BUILD_SHOW_FUNC_INT(slots_fan_pwm, slots_state.pwm)
 764
 765 BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
 766
 767 static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
 768 static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
 769 static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
 770 static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
 771 static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
 772
 773 static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
 774 static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
 775 static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
 776 static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
 777 static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
 778
 779 static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
 780 static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
 781
 782 static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
 783 static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
 784
 785 static DEVICE_ATTR(slots_temperature,S_IRUGO,show_slots_temperature,NULL);
 786 static DEVICE_ATTR(slots_fan_pwm,S_IRUGO,show_slots_fan_pwm,NULL);
 787
 788 static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
 789
 790 /*
 791  * CPUs fans control loop
 792  */
 793
 794 static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
 795 {
 796         s32 ltemp, volts, amps;
 797         int index, rc = 0;
 798
 799         /* Default (in case of error) */
 800         *temp = state->cur_temp;
 801         *power = state->cur_power;
 802
 803         if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
 804                 index = (state->index == 0) ?
 805                         CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
 806         else
 807                 index = (state->index == 0) ?
 808                         CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
 809
 810         /* Read current fan status */
 811         rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
 812         if (rc < 0) {
 813                 /* XXX What do we do now ? Nothing for now, keep old value, but
 814                  * return error upstream
 815                  */
 816                 DBG("  cpu %d, fan reading error !\n", state->index);
 817         } else {
 818                 state->rpm = rc;
 819                 DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
 820         }
 821
 822         /* Get some sensor readings and scale it */
 823         ltemp = read_smon_adc(state, 1);
 824         if (ltemp == -1) {
 825                 /* XXX What do we do now ? */
 826                 state->overtemp++;
 827                 if (rc == 0)
 828                         rc = -EIO;
 829                 DBG("  cpu %d, temp reading error !\n", state->index);
 830         } else {
 831                 /* Fixup temperature according to diode calibration
 832                  */
 833                 DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
 834                     state->index,
 835                     ltemp, state->mpu.mdiode, state->mpu.bdiode);
 836                 *temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
 837                 state->last_temp = *temp;
 838                 DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
 839         }
 840
 841         /*
 842          * Read voltage & current and calculate power
 843          */
 844         volts = read_smon_adc(state, 3);
 845         amps = read_smon_adc(state, 4);
 846
 847         /* Scale voltage and current raw sensor values according to fixed scales
 848          * obtained in Darwin and calculate power from I and V
 849          */
 850         volts *= ADC_CPU_VOLTAGE_SCALE;
 851         amps *= ADC_CPU_CURRENT_SCALE;
 852         *power = (((u64)volts) * ((u64)amps)) >> 16;
 853         state->voltage = volts;
 854         state->current_a = amps;
 855         state->last_power = *power;
 856
 857         DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
 858             state->index, FIX32TOPRINT(state->current_a),
 859             FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
 860
 861         return 0;
 862 }
 863
 864 static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
 865 {
 866         s32 power_target, integral, derivative, proportional, adj_in_target, sval;
 867         s64 integ_p, deriv_p, prop_p, sum;
 868         int i;
 869
 870         /* Calculate power target value (could be done once for all)
 871          * and convert to a 16.16 fp number
 872          */
 873         power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
 874         DBG("  power target: %d.%03d, error: %d.%03d\n",
 875             FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
 876
 877         /* Store temperature and power in history array */
 878         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 879         state->temp_history[state->cur_temp] = temp;
 880         state->cur_power = (state->cur_power + 1) % state->count_power;
 881         state->power_history[state->cur_power] = power;
 882         state->error_history[state->cur_power] = power_target - power;
 883
 884         /* If first loop, fill the history table */
 885         if (state->first) {
 886                 for (i = 0; i < (state->count_power - 1); i++) {
 887                         state->cur_power = (state->cur_power + 1) % state->count_power;
 888                         state->power_history[state->cur_power] = power;
 889                         state->error_history[state->cur_power] = power_target - power;
 890                 }
 891                 for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
 892                         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 893                         state->temp_history[state->cur_temp] = temp;
 894                 }
 895                 state->first = 0;
 896         }
 897
 898         /* Calculate the integral term normally based on the "power" values */
 899         sum = 0;
 900         integral = 0;
 901         for (i = 0; i < state->count_power; i++)
 902                 integral += state->error_history[i];
 903         integral *= CPU_PID_INTERVAL;
 904         DBG("  integral: %08x\n", integral);
 905
 906         /* Calculate the adjusted input (sense value).
 907          *   G_r is 12.20
 908          *   integ is 16.16
 909          *   so the result is 28.36
 910          *
 911          * input target is mpu.ttarget, input max is mpu.tmax
 912          */
 913         integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
 914         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
 915         sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
 916         adj_in_target = (state->mpu.ttarget << 16);
 917         if (adj_in_target > sval)
 918                 adj_in_target = sval;
 919         DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
 920             state->mpu.ttarget);
 921
 922         /* Calculate the derivative term */
 923         derivative = state->temp_history[state->cur_temp] -
 924                 state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
 925                                     % CPU_TEMP_HISTORY_SIZE];
 926         derivative /= CPU_PID_INTERVAL;
 927         deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
 928         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
 929         sum += deriv_p;
 930
 931         /* Calculate the proportional term */
 932         proportional = temp - adj_in_target;
 933         prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
 934         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
 935         sum += prop_p;
 936
 937         /* Scale sum */
 938         sum >>= 36;
 939
 940         DBG("   sum: %d\n", (int)sum);
 941         state->rpm += (s32)sum;
 942 }
 943
 944 static void do_monitor_cpu_combined(void)
 945 {
 946         struct cpu_pid_state *state0 = &cpu_state[0];
 947         struct cpu_pid_state *state1 = &cpu_state[1];
 948         s32 temp0, power0, temp1, power1;
 949         s32 temp_combi, power_combi;
 950         int rc, intake, pump;
 951
 952         rc = do_read_one_cpu_values(state0, &temp0, &power0);
 953         if (rc < 0) {
 954                 /* XXX What do we do now ? */
 955         }
 956         state1->overtemp = 0;
 957         rc = do_read_one_cpu_values(state1, &temp1, &power1);
 958         if (rc < 0) {
 959                 /* XXX What do we do now ? */
 960         }
 961         if (state1->overtemp)
 962                 state0->overtemp++;
 963
 964         temp_combi = max(temp0, temp1);
 965         power_combi = max(power0, power1);
 966
 967         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
 968          * full blown immediately and try to trigger a shutdown
 969          */
 970         if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
 971                 printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
 972                        temp_combi >> 16);
 973                 state0->overtemp += CPU_MAX_OVERTEMP / 4;
 974         } else if (temp_combi > (state0->mpu.tmax << 16))
 975                 state0->overtemp++;
 976         else
 977                 state0->overtemp = 0;
 978         if (state0->overtemp >= CPU_MAX_OVERTEMP)
 979                 critical_state = 1;
 980         if (state0->overtemp > 0) {
 981                 state0->rpm = state0->mpu.rmaxn_exhaust_fan;
 982                 state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
 983                 pump = state0->pump_max;
 984                 goto do_set_fans;
 985         }
 986
 987         /* Do the PID */
 988         do_cpu_pid(state0, temp_combi, power_combi);
 989
 990         /* Range check */
 991         state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
 992         state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
 993
 994         /* Calculate intake fan speed */
 995         intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
 996         intake = max(intake, (int)state0->mpu.rminn_intake_fan);
 997         intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
 998         state0->intake_rpm = intake;
 999
1000         /* Calculate pump speed */
1001         pump = (state0->rpm * state0->pump_max) /
1002                 state0->mpu.rmaxn_exhaust_fan;
1003         pump = min(pump, state0->pump_max);
1004         pump = max(pump, state0->pump_min);
1005
1006  do_set_fans:
1007         /* We copy values from state 0 to state 1 for /sysfs */
1008         state1->rpm = state0->rpm;
1009         state1->intake_rpm = state0->intake_rpm;
1010
1011         DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
1012             state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
1013
1014         /* We should check for errors, shouldn't we ? But then, what
1015          * do we do once the error occurs ? For FCU notified fan
1016          * failures (-EFAULT) we probably want to notify userland
1017          * some way...
1018          */
1019         set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1020         set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1021         set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1022         set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1023
1024         if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1025                 set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
1026         if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1027                 set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
1028 }
1029
1030 static void do_monitor_cpu_split(struct cpu_pid_state *state)
1031 {
1032         s32 temp, power;
1033         int rc, intake;
1034
1035         /* Read current fan status */
1036         rc = do_read_one_cpu_values(state, &temp, &power);
1037         if (rc < 0) {
1038                 /* XXX What do we do now ? */
1039         }
1040
1041         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1042          * full blown immediately and try to trigger a shutdown
1043          */
1044         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1045                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1046                        " (%d) !\n",
1047                        state->index, temp >> 16);
1048                 state->overtemp += CPU_MAX_OVERTEMP / 4;
1049         } else if (temp > (state->mpu.tmax << 16))
1050                 state->overtemp++;
1051         else
1052                 state->overtemp = 0;
1053         if (state->overtemp >= CPU_MAX_OVERTEMP)
1054                 critical_state = 1;
1055         if (state->overtemp > 0) {
1056                 state->rpm = state->mpu.rmaxn_exhaust_fan;
1057                 state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1058                 goto do_set_fans;
1059         }
1060
1061         /* Do the PID */
1062         do_cpu_pid(state, temp, power);
1063
1064         /* Range check */
1065         state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1066         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1067
1068         /* Calculate intake fan */
1069         intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1070         intake = max(intake, (int)state->mpu.rminn_intake_fan);
1071         intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1072         state->intake_rpm = intake;
1073
1074  do_set_fans:
1075         DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1076             state->index, (int)state->rpm, intake, state->overtemp);
1077
1078         /* We should check for errors, shouldn't we ? But then, what
1079          * do we do once the error occurs ? For FCU notified fan
1080          * failures (-EFAULT) we probably want to notify userland
1081          * some way...
1082          */
1083         if (state->index == 0) {
1084                 set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1085                 set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1086         } else {
1087                 set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1088                 set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1089         }
1090 }
1091
1092 static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1093 {
1094         s32 temp, power, fan_min;
1095         int rc;
1096
1097         /* Read current fan status */
1098         rc = do_read_one_cpu_values(state, &temp, &power);
1099         if (rc < 0) {
1100                 /* XXX What do we do now ? */
1101         }
1102
1103         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1104          * full blown immediately and try to trigger a shutdown
1105          */
1106         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1107                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1108                        " (%d) !\n",
1109                        state->index, temp >> 16);
1110                 state->overtemp = CPU_MAX_OVERTEMP / 4;
1111         } else if (temp > (state->mpu.tmax << 16))
1112                 state->overtemp++;
1113         else
1114                 state->overtemp = 0;
1115         if (state->overtemp >= CPU_MAX_OVERTEMP)
1116                 critical_state = 1;
1117         if (state->overtemp > 0) {
1118                 state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1119                 goto do_set_fans;
1120         }
1121
1122         /* Do the PID */
1123         do_cpu_pid(state, temp, power);
1124
1125         /* Check clamp from dimms */
1126         fan_min = dimm_output_clamp;
1127         fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1128
1129         DBG(" CPU min mpu = %d, min dimm = %d\n",
1130             state->mpu.rminn_intake_fan, dimm_output_clamp);
1131
1132         state->rpm = max(state->rpm, (int)fan_min);
1133         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1134         state->intake_rpm = state->rpm;
1135
1136  do_set_fans:
1137         DBG("** CPU %d RPM: %d overtemp: %d\n",
1138             state->index, (int)state->rpm, state->overtemp);
1139
1140         /* We should check for errors, shouldn't we ? But then, what
1141          * do we do once the error occurs ? For FCU notified fan
1142          * failures (-EFAULT) we probably want to notify userland
1143          * some way...
1144          */
1145         if (state->index == 0) {
1146                 set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1147                 set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1148                 set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1149         } else {
1150                 set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1151                 set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1152                 set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1153         }
1154 }
1155
1156 /*
1157  * Initialize the state structure for one CPU control loop
1158  */
1159 static int init_cpu_state(struct cpu_pid_state *state, int index)
1160 {
1161         int err;
1162
1163         state->index = index;
1164         state->first = 1;
1165         state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1166         state->overtemp = 0;
1167         state->adc_config = 0x00;
1168
1169
1170         if (index == 0)
1171                 state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1172         else if (index == 1)
1173                 state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1174         if (state->monitor == NULL)
1175                 goto fail;
1176
1177         if (read_eeprom(index, &state->mpu))
1178                 goto fail;
1179
1180         state->count_power = state->mpu.tguardband;
1181         if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1182                 printk(KERN_WARNING "Warning ! too many power history slots\n");
1183                 state->count_power = CPU_POWER_HISTORY_SIZE;
1184         }
1185         DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1186
1187         if (index == 0) {
1188                 err = device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1189                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1190                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1191                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1192                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1193         } else {
1194                 err = device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1195                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1196                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1197                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1198                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1199         }
1200         if (err)
1201                 printk(KERN_WARNING "Failed to create some of the atribute"
1202                         "files for CPU %d\n", index);
1203
1204         return 0;
1205  fail:
1206         if (state->monitor)
1207                 detach_i2c_chip(state->monitor);
1208         state->monitor = NULL;
1209
1210         return -ENODEV;
1211 }
1212
1213 /*
1214  * Dispose of the state data for one CPU control loop
1215  */
1216 static void dispose_cpu_state(struct cpu_pid_state *state)
1217 {
1218         if (state->monitor == NULL)
1219                 return;
1220
1221         if (state->index == 0) {
1222                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1223                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1224                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1225                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1226                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1227         } else {
1228                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1229                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1230                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1231                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1232                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1233         }
1234
1235         detach_i2c_chip(state->monitor);
1236         state->monitor = NULL;
1237 }
1238
1239 /*
1240  * Motherboard backside & U3 heatsink fan control loop
1241  */
1242 static void do_monitor_backside(struct backside_pid_state *state)
1243 {
1244         s32 temp, integral, derivative, fan_min;
1245         s64 integ_p, deriv_p, prop_p, sum;
1246         int i, rc;
1247
1248         if (--state->ticks != 0)
1249                 return;
1250         state->ticks = backside_params.interval;
1251
1252         DBG("backside:\n");
1253
1254         /* Check fan status */
1255         rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1256         if (rc < 0) {
1257                 printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1258                 /* XXX What do we do now ? */
1259         } else
1260                 state->pwm = rc;
1261         DBG("  current pwm: %d\n", state->pwm);
1262
1263         /* Get some sensor readings */
1264         temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1265         state->last_temp = temp;
1266         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1267             FIX32TOPRINT(backside_params.input_target));
1268
1269         /* Store temperature and error in history array */
1270         state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1271         state->sample_history[state->cur_sample] = temp;
1272         state->error_history[state->cur_sample] = temp - backside_params.input_target;
1273
1274         /* If first loop, fill the history table */
1275         if (state->first) {
1276                 for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1277                         state->cur_sample = (state->cur_sample + 1) %
1278                                 BACKSIDE_PID_HISTORY_SIZE;
1279                         state->sample_history[state->cur_sample] = temp;
1280                         state->error_history[state->cur_sample] =
1281                                 temp - backside_params.input_target;
1282                 }
1283                 state->first = 0;
1284         }
1285
1286         /* Calculate the integral term */
1287         sum = 0;
1288         integral = 0;
1289         for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1290                 integral += state->error_history[i];
1291         integral *= backside_params.interval;
1292         DBG("  integral: %08x\n", integral);
1293         integ_p = ((s64)backside_params.G_r) * (s64)integral;
1294         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1295         sum += integ_p;
1296
1297         /* Calculate the derivative term */
1298         derivative = state->error_history[state->cur_sample] -
1299                 state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1300                                     % BACKSIDE_PID_HISTORY_SIZE];
1301         derivative /= backside_params.interval;
1302         deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1303         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1304         sum += deriv_p;
1305
1306         /* Calculate the proportional term */
1307         prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1308         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1309         sum += prop_p;
1310
1311         /* Scale sum */
1312         sum >>= 36;
1313
1314         DBG("   sum: %d\n", (int)sum);
1315         if (backside_params.additive)
1316                 state->pwm += (s32)sum;
1317         else
1318                 state->pwm = sum;
1319
1320         /* Check for clamp */
1321         fan_min = (dimm_output_clamp * 100) / 14000;
1322         fan_min = max(fan_min, backside_params.output_min);
1323
1324         state->pwm = max(state->pwm, fan_min);
1325         state->pwm = min(state->pwm, backside_params.output_max);
1326
1327         DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1328         set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1329 }
1330
1331 /*
1332  * Initialize the state structure for the backside fan control loop
1333  */
1334 static int init_backside_state(struct backside_pid_state *state)
1335 {
1336         struct device_node *u3;
1337         int u3h = 1; /* conservative by default */
1338         int err;
1339
1340         /*
1341          * There are different PID params for machines with U3 and machines
1342          * with U3H, pick the right ones now
1343          */
1344         u3 = of_find_node_by_path("/u3@0,f8000000");
1345         if (u3 != NULL) {
1346                 const u32 *vers = of_get_property(u3, "device-rev", NULL);
1347                 if (vers)
1348                         if (((*vers) & 0x3f) < 0x34)
1349                                 u3h = 0;
1350                 of_node_put(u3);
1351         }
1352
1353         if (rackmac) {
1354                 backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1355                 backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1356                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1357                 backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1358                 backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1359                 backside_params.G_r = BACKSIDE_PID_G_r;
1360                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1361                 backside_params.additive = 0;
1362         } else if (u3h) {
1363                 backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1364                 backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1365                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1366                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1367                 backside_params.G_p = BACKSIDE_PID_G_p;
1368                 backside_params.G_r = BACKSIDE_PID_G_r;
1369                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1370                 backside_params.additive = 1;
1371         } else {
1372                 backside_params.G_d = BACKSIDE_PID_U3_G_d;
1373                 backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1374                 backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1375                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1376                 backside_params.G_p = BACKSIDE_PID_G_p;
1377                 backside_params.G_r = BACKSIDE_PID_G_r;
1378                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1379                 backside_params.additive = 1;
1380         }
1381
1382         state->ticks = 1;
1383         state->first = 1;
1384         state->pwm = 50;
1385
1386         state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1387         if (state->monitor == NULL)
1388                 return -ENODEV;
1389
1390         err = device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1391         err |= device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1392         if (err)
1393                 printk(KERN_WARNING "Failed to create attribute file(s)"
1394                         " for backside fan\n");
1395
1396         return 0;
1397 }
1398
1399 /*
1400  * Dispose of the state data for the backside control loop
1401  */
1402 static void dispose_backside_state(struct backside_pid_state *state)
1403 {
1404         if (state->monitor == NULL)
1405                 return;
1406
1407         device_remove_file(&of_dev->dev, &dev_attr_backside_temperature);
1408         device_remove_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1409
1410         detach_i2c_chip(state->monitor);
1411         state->monitor = NULL;
1412 }
1413
1414 /*
1415  * Drives bay fan control loop
1416  */
1417 static void do_monitor_drives(struct drives_pid_state *state)
1418 {
1419         s32 temp, integral, derivative;
1420         s64 integ_p, deriv_p, prop_p, sum;
1421         int i, rc;
1422
1423         if (--state->ticks != 0)
1424                 return;
1425         state->ticks = DRIVES_PID_INTERVAL;
1426
1427         DBG("drives:\n");
1428
1429         /* Check fan status */
1430         rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1431         if (rc < 0) {
1432                 printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1433                 /* XXX What do we do now ? */
1434         } else
1435                 state->rpm = rc;
1436         DBG("  current rpm: %d\n", state->rpm);
1437
1438         /* Get some sensor readings */
1439         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1440                                                     DS1775_TEMP)) << 8;
1441         state->last_temp = temp;
1442         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1443             FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1444
1445         /* Store temperature and error in history array */
1446         state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1447         state->sample_history[state->cur_sample] = temp;
1448         state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1449
1450         /* If first loop, fill the history table */
1451         if (state->first) {
1452                 for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1453                         state->cur_sample = (state->cur_sample + 1) %
1454                                 DRIVES_PID_HISTORY_SIZE;
1455                         state->sample_history[state->cur_sample] = temp;
1456                         state->error_history[state->cur_sample] =
1457                                 temp - DRIVES_PID_INPUT_TARGET;
1458                 }
1459                 state->first = 0;
1460         }
1461
1462         /* Calculate the integral term */
1463         sum = 0;
1464         integral = 0;
1465         for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1466                 integral += state->error_history[i];
1467         integral *= DRIVES_PID_INTERVAL;
1468         DBG("  integral: %08x\n", integral);
1469         integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1470         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1471         sum += integ_p;
1472
1473         /* Calculate the derivative term */
1474         derivative = state->error_history[state->cur_sample] -
1475                 state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1476                                     % DRIVES_PID_HISTORY_SIZE];
1477         derivative /= DRIVES_PID_INTERVAL;
1478         deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1479         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1480         sum += deriv_p;
1481
1482         /* Calculate the proportional term */
1483         prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1484         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1485         sum += prop_p;
1486
1487         /* Scale sum */
1488         sum >>= 36;
1489
1490         DBG("   sum: %d\n", (int)sum);
1491         state->rpm += (s32)sum;
1492
1493         state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1494         state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1495
1496         DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1497         set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1498 }
1499
1500 /*
1501  * Initialize the state structure for the drives bay fan control loop
1502  */
1503 static int init_drives_state(struct drives_pid_state *state)
1504 {
1505         int err;
1506
1507         state->ticks = 1;
1508         state->first = 1;
1509         state->rpm = 1000;
1510
1511         state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1512         if (state->monitor == NULL)
1513                 return -ENODEV;
1514
1515         err = device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1516         err |= device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1517         if (err)
1518                 printk(KERN_WARNING "Failed to create attribute file(s)"
1519                         " for drives bay fan\n");
1520
1521         return 0;
1522 }
1523
1524 /*
1525  * Dispose of the state data for the drives control loop
1526  */
1527 static void dispose_drives_state(struct drives_pid_state *state)
1528 {
1529         if (state->monitor == NULL)
1530                 return;
1531
1532         device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1533         device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1534
1535         detach_i2c_chip(state->monitor);
1536         state->monitor = NULL;
1537 }
1538
1539 /*
1540  * DIMMs temp control loop
1541  */
1542 static void do_monitor_dimms(struct dimm_pid_state *state)
1543 {
1544         s32 temp, integral, derivative, fan_min;
1545         s64 integ_p, deriv_p, prop_p, sum;
1546         int i;
1547
1548         if (--state->ticks != 0)
1549                 return;
1550         state->ticks = DIMM_PID_INTERVAL;
1551
1552         DBG("DIMM:\n");
1553
1554         DBG("  current value: %d\n", state->output);
1555
1556         temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1557         if (temp < 0)
1558                 return;
1559         temp <<= 16;
1560         state->last_temp = temp;
1561         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1562             FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1563
1564         /* Store temperature and error in history array */
1565         state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1566         state->sample_history[state->cur_sample] = temp;
1567         state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1568
1569         /* If first loop, fill the history table */
1570         if (state->first) {
1571                 for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1572                         state->cur_sample = (state->cur_sample + 1) %
1573                                 DIMM_PID_HISTORY_SIZE;
1574                         state->sample_history[state->cur_sample] = temp;
1575                         state->error_history[state->cur_sample] =
1576                                 temp - DIMM_PID_INPUT_TARGET;
1577                 }
1578                 state->first = 0;
1579         }
1580
1581         /* Calculate the integral term */
1582         sum = 0;
1583         integral = 0;
1584         for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1585                 integral += state->error_history[i];
1586         integral *= DIMM_PID_INTERVAL;
1587         DBG("  integral: %08x\n", integral);
1588         integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1589         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1590         sum += integ_p;
1591
1592         /* Calculate the derivative term */
1593         derivative = state->error_history[state->cur_sample] -
1594                 state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1595                                     % DIMM_PID_HISTORY_SIZE];
1596         derivative /= DIMM_PID_INTERVAL;
1597         deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1598         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1599         sum += deriv_p;
1600
1601         /* Calculate the proportional term */
1602         prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1603         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1604         sum += prop_p;
1605
1606         /* Scale sum */
1607         sum >>= 36;
1608
1609         DBG("   sum: %d\n", (int)sum);
1610         state->output = (s32)sum;
1611         state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1612         state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1613         dimm_output_clamp = state->output;
1614
1615         DBG("** DIMM clamp value: %d\n", (int)state->output);
1616
1617         /* Backside PID is only every 5 seconds, force backside fan clamping now */
1618         fan_min = (dimm_output_clamp * 100) / 14000;
1619         fan_min = max(fan_min, backside_params.output_min);
1620         if (backside_state.pwm < fan_min) {
1621                 backside_state.pwm = fan_min;
1622                 DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1623                 set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1624         }
1625 }
1626
1627 /*
1628  * Initialize the state structure for the DIMM temp control loop
1629  */
1630 static int init_dimms_state(struct dimm_pid_state *state)
1631 {
1632         state->ticks = 1;
1633         state->first = 1;
1634         state->output = 4000;
1635
1636         state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1637         if (state->monitor == NULL)
1638                 return -ENODEV;
1639
1640         if (device_create_file(&of_dev->dev, &dev_attr_dimms_temperature))
1641                 printk(KERN_WARNING "Failed to create attribute file"
1642                         " for DIMM temperature\n");
1643
1644         return 0;
1645 }
1646
1647 /*
1648  * Dispose of the state data for the DIMM control loop
1649  */
1650 static void dispose_dimms_state(struct dimm_pid_state *state)
1651 {
1652         if (state->monitor == NULL)
1653                 return;
1654
1655         device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1656
1657         detach_i2c_chip(state->monitor);
1658         state->monitor = NULL;
1659 }
1660
1661 /*
1662  * Slots fan control loop
1663  */
1664 static void do_monitor_slots(struct slots_pid_state *state)
1665 {
1666         s32 temp, integral, derivative;
1667         s64 integ_p, deriv_p, prop_p, sum;
1668         int i, rc;
1669
1670         if (--state->ticks != 0)
1671                 return;
1672         state->ticks = SLOTS_PID_INTERVAL;
1673
1674         DBG("slots:\n");
1675
1676         /* Check fan status */
1677         rc = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
1678         if (rc < 0) {
1679                 printk(KERN_WARNING "Error %d reading slots fan !\n", rc);
1680                 /* XXX What do we do now ? */
1681         } else
1682                 state->pwm = rc;
1683         DBG("  current pwm: %d\n", state->pwm);
1684
1685         /* Get some sensor readings */
1686         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1687                                                     DS1775_TEMP)) << 8;
1688         state->last_temp = temp;
1689         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1690             FIX32TOPRINT(SLOTS_PID_INPUT_TARGET));
1691
1692         /* Store temperature and error in history array */
1693         state->cur_sample = (state->cur_sample + 1) % SLOTS_PID_HISTORY_SIZE;
1694         state->sample_history[state->cur_sample] = temp;
1695         state->error_history[state->cur_sample] = temp - SLOTS_PID_INPUT_TARGET;
1696
1697         /* If first loop, fill the history table */
1698         if (state->first) {
1699                 for (i = 0; i < (SLOTS_PID_HISTORY_SIZE - 1); i++) {
1700                         state->cur_sample = (state->cur_sample + 1) %
1701                                 SLOTS_PID_HISTORY_SIZE;
1702                         state->sample_history[state->cur_sample] = temp;
1703                         state->error_history[state->cur_sample] =
1704                                 temp - SLOTS_PID_INPUT_TARGET;
1705                 }
1706                 state->first = 0;
1707         }
1708
1709         /* Calculate the integral term */
1710         sum = 0;
1711         integral = 0;
1712         for (i = 0; i < SLOTS_PID_HISTORY_SIZE; i++)
1713                 integral += state->error_history[i];
1714         integral *= SLOTS_PID_INTERVAL;
1715         DBG("  integral: %08x\n", integral);
1716         integ_p = ((s64)SLOTS_PID_G_r) * (s64)integral;
1717         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1718         sum += integ_p;
1719
1720         /* Calculate the derivative term */
1721         derivative = state->error_history[state->cur_sample] -
1722                 state->error_history[(state->cur_sample + SLOTS_PID_HISTORY_SIZE - 1)
1723                                     % SLOTS_PID_HISTORY_SIZE];
1724         derivative /= SLOTS_PID_INTERVAL;
1725         deriv_p = ((s64)SLOTS_PID_G_d) * (s64)derivative;
1726         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1727         sum += deriv_p;
1728
1729         /* Calculate the proportional term */
1730         prop_p = ((s64)SLOTS_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1731         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1732         sum += prop_p;
1733
1734         /* Scale sum */
1735         sum >>= 36;
1736
1737         DBG("   sum: %d\n", (int)sum);
1738         state->pwm = (s32)sum;
1739
1740         state->pwm = max(state->pwm, SLOTS_PID_OUTPUT_MIN);
1741         state->pwm = min(state->pwm, SLOTS_PID_OUTPUT_MAX);
1742
1743         DBG("** DRIVES PWM: %d\n", (int)state->pwm);
1744         set_pwm_fan(SLOTS_FAN_PWM_INDEX, state->pwm);
1745 }
1746
1747 /*
1748  * Initialize the state structure for the slots bay fan control loop
1749  */
1750 static int init_slots_state(struct slots_pid_state *state)
1751 {
1752         int err;
1753
1754         state->ticks = 1;
1755         state->first = 1;
1756         state->pwm = 50;
1757
1758         state->monitor = attach_i2c_chip(XSERVE_SLOTS_LM75, "slots_temp");
1759         if (state->monitor == NULL)
1760                 return -ENODEV;
1761
1762         err = device_create_file(&of_dev->dev, &dev_attr_slots_temperature);
1763         err |= device_create_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1764         if (err)
1765                 printk(KERN_WARNING "Failed to create attribute file(s)"
1766                         " for slots bay fan\n");
1767
1768         return 0;
1769 }
1770
1771 /*
1772  * Dispose of the state data for the slots control loop
1773  */
1774 static void dispose_slots_state(struct slots_pid_state *state)
1775 {
1776         if (state->monitor == NULL)
1777                 return;
1778
1779         device_remove_file(&of_dev->dev, &dev_attr_slots_temperature);
1780         device_remove_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1781
1782         detach_i2c_chip(state->monitor);
1783         state->monitor = NULL;
1784 }
1785
1786
1787 static int call_critical_overtemp(void)
1788 {
1789         char *argv[] = { critical_overtemp_path, NULL };
1790         static char *envp[] = { "HOME=/",
1791                                 "TERM=linux",
1792                                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1793                                 NULL };
1794
1795         return call_usermodehelper(critical_overtemp_path,
1796                                    argv, envp, UMH_WAIT_EXEC);
1797 }
1798
1799
1800 /*
1801  * Here's the kernel thread that calls the various control loops
1802  */
1803 static int main_control_loop(void *x)
1804 {
1805         DBG("main_control_loop started\n");
1806
1807         mutex_lock(&driver_lock);
1808
1809         if (start_fcu() < 0) {
1810                 printk(KERN_ERR "kfand: failed to start FCU\n");
1811                 mutex_unlock(&driver_lock);
1812                 goto out;
1813         }
1814
1815         /* Set the PCI fan once for now on non-RackMac */
1816         if (!rackmac)
1817                 set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1818
1819         /* Initialize ADCs */
1820         initialize_adc(&cpu_state[0]);
1821         if (cpu_state[1].monitor != NULL)
1822                 initialize_adc(&cpu_state[1]);
1823
1824         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1825
1826         mutex_unlock(&driver_lock);
1827
1828         while (state == state_attached) {
1829                 unsigned long elapsed, start;
1830
1831                 start = jiffies;
1832
1833                 mutex_lock(&driver_lock);
1834
1835                 /* Tickle the FCU just in case */
1836                 if (--fcu_tickle_ticks < 0) {
1837                         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1838                         tickle_fcu();
1839                 }
1840
1841                 /* First, we always calculate the new DIMMs state on an Xserve */
1842                 if (rackmac)
1843                         do_monitor_dimms(&dimms_state);
1844
1845                 /* Then, the CPUs */
1846                 if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1847                         do_monitor_cpu_combined();
1848                 else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1849                         do_monitor_cpu_rack(&cpu_state[0]);
1850                         if (cpu_state[1].monitor != NULL)
1851                                 do_monitor_cpu_rack(&cpu_state[1]);
1852                         // better deal with UP
1853                 } else {
1854                         do_monitor_cpu_split(&cpu_state[0]);
1855                         if (cpu_state[1].monitor != NULL)
1856                                 do_monitor_cpu_split(&cpu_state[1]);
1857                         // better deal with UP
1858                 }
1859                 /* Then, the rest */
1860                 do_monitor_backside(&backside_state);
1861                 if (rackmac)
1862                         do_monitor_slots(&slots_state);
1863                 else
1864                         do_monitor_drives(&drives_state);
1865                 mutex_unlock(&driver_lock);
1866
1867                 if (critical_state == 1) {
1868                         printk(KERN_WARNING "Temperature control detected a critical condition\n");
1869                         printk(KERN_WARNING "Attempting to shut down...\n");
1870                         if (call_critical_overtemp()) {
1871                                 printk(KERN_WARNING "Can't call %s, power off now!\n",
1872                                        critical_overtemp_path);
1873                                 machine_power_off();
1874                         }
1875                 }
1876                 if (critical_state > 0)
1877                         critical_state++;
1878                 if (critical_state > MAX_CRITICAL_STATE) {
1879                         printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1880                         machine_power_off();
1881                 }
1882
1883                 // FIXME: Deal with signals
1884                 elapsed = jiffies - start;
1885                 if (elapsed < HZ)
1886                         schedule_timeout_interruptible(HZ - elapsed);
1887         }
1888
1889  out:
1890         DBG("main_control_loop ended\n");
1891
1892         ctrl_task = 0;
1893         complete_and_exit(&ctrl_complete, 0);
1894 }
1895
1896 /*
1897  * Dispose the control loops when tearing down
1898  */
1899 static void dispose_control_loops(void)
1900 {
1901         dispose_cpu_state(&cpu_state[0]);
1902         dispose_cpu_state(&cpu_state[1]);
1903         dispose_backside_state(&backside_state);
1904         dispose_drives_state(&drives_state);
1905         dispose_slots_state(&slots_state);
1906         dispose_dimms_state(&dimms_state);
1907 }
1908
1909 /*
1910  * Create the control loops. U3-0 i2c bus is up, so we can now
1911  * get to the various sensors
1912  */
1913 static int create_control_loops(void)
1914 {
1915         struct device_node *np;
1916
1917         /* Count CPUs from the device-tree, we don't care how many are
1918          * actually used by Linux
1919          */
1920         cpu_count = 0;
1921         for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1922                 cpu_count++;
1923
1924         DBG("counted %d CPUs in the device-tree\n", cpu_count);
1925
1926         /* Decide the type of PID algorithm to use based on the presence of
1927          * the pumps, though that may not be the best way, that is good enough
1928          * for now
1929          */
1930         if (rackmac)
1931                 cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1932         else if (machine_is_compatible("PowerMac7,3")
1933             && (cpu_count > 1)
1934             && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1935             && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1936                 printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1937                 cpu_pid_type = CPU_PID_TYPE_COMBINED;
1938         } else
1939                 cpu_pid_type = CPU_PID_TYPE_SPLIT;
1940
1941         /* Create control loops for everything. If any fail, everything
1942          * fails
1943          */
1944         if (init_cpu_state(&cpu_state[0], 0))
1945                 goto fail;
1946         if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1947                 fetch_cpu_pumps_minmax();
1948
1949         if (cpu_count > 1 && init_cpu_state(&cpu_state[1], 1))
1950                 goto fail;
1951         if (init_backside_state(&backside_state))
1952                 goto fail;
1953         if (rackmac && init_dimms_state(&dimms_state))
1954                 goto fail;
1955         if (rackmac && init_slots_state(&slots_state))
1956                 goto fail;
1957         if (!rackmac && init_drives_state(&drives_state))
1958                 goto fail;
1959
1960         DBG("all control loops up !\n");
1961
1962         return 0;
1963
1964  fail:
1965         DBG("failure creating control loops, disposing\n");
1966
1967         dispose_control_loops();
1968
1969         return -ENODEV;
1970 }
1971
1972 /*
1973  * Start the control loops after everything is up, that is create
1974  * the thread that will make them run
1975  */
1976 static void start_control_loops(void)
1977 {
1978         init_completion(&ctrl_complete);
1979
1980         ctrl_task = kthread_run(main_control_loop, NULL, "kfand");
1981 }
1982
1983 /*
1984  * Stop the control loops when tearing down
1985  */
1986 static void stop_control_loops(void)
1987 {
1988         if (ctrl_task)
1989                 wait_for_completion(&ctrl_complete);
1990 }
1991
1992 /*
1993  * Attach to the i2c FCU after detecting U3-1 bus
1994  */
1995 static int attach_fcu(void)
1996 {
1997         fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1998         if (fcu == NULL)
1999                 return -ENODEV;
2000
2001         DBG("FCU attached\n");
2002
2003         return 0;
2004 }
2005
2006 /*
2007  * Detach from the i2c FCU when tearing down
2008  */
2009 static void detach_fcu(void)
2010 {
2011         if (fcu)
2012                 detach_i2c_chip(fcu);
2013         fcu = NULL;
2014 }
2015
2016 /*
2017  * Attach to the i2c controller. We probe the various chips based
2018  * on the device-tree nodes and build everything for the driver to
2019  * run, we then kick the driver monitoring thread
2020  */
2021 static int therm_pm72_attach(struct i2c_adapter *adapter)
2022 {
2023         mutex_lock(&driver_lock);
2024
2025         /* Check state */
2026         if (state == state_detached)
2027                 state = state_attaching;
2028         if (state != state_attaching) {
2029                 mutex_unlock(&driver_lock);
2030                 return 0;
2031         }
2032
2033         /* Check if we are looking for one of these */
2034         if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
2035                 u3_0 = adapter;
2036                 DBG("found U3-0\n");
2037                 if (k2 || !rackmac)
2038                         if (create_control_loops())
2039                                 u3_0 = NULL;
2040         } else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
2041                 u3_1 = adapter;
2042                 DBG("found U3-1, attaching FCU\n");
2043                 if (attach_fcu())
2044                         u3_1 = NULL;
2045         } else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
2046                 k2 = adapter;
2047                 DBG("Found K2\n");
2048                 if (u3_0 && rackmac)
2049                         if (create_control_loops())
2050                                 k2 = NULL;
2051         }
2052         /* We got all we need, start control loops */
2053         if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
2054                 DBG("everything up, starting control loops\n");
2055                 state = state_attached;
2056                 start_control_loops();
2057         }
2058         mutex_unlock(&driver_lock);
2059
2060         return 0;
2061 }
2062
2063 /*
2064  * Called on every adapter when the driver or the i2c controller
2065  * is going away.
2066  */
2067 static int therm_pm72_detach(struct i2c_adapter *adapter)
2068 {
2069         mutex_lock(&driver_lock);
2070
2071         if (state != state_detached)
2072                 state = state_detaching;
2073
2074         /* Stop control loops if any */
2075         DBG("stopping control loops\n");
2076         mutex_unlock(&driver_lock);
2077         stop_control_loops();
2078         mutex_lock(&driver_lock);
2079
2080         if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
2081                 DBG("lost U3-0, disposing control loops\n");
2082                 dispose_control_loops();
2083                 u3_0 = NULL;
2084         }
2085
2086         if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
2087                 DBG("lost U3-1, detaching FCU\n");
2088                 detach_fcu();
2089                 u3_1 = NULL;
2090         }
2091         if (u3_0 == NULL && u3_1 == NULL)
2092                 state = state_detached;
2093
2094         mutex_unlock(&driver_lock);
2095
2096         return 0;
2097 }
2098
2099 static int fan_check_loc_match(const char *loc, int fan)
2100 {
2101         char    tmp[64];
2102         char    *c, *e;
2103
2104         strlcpy(tmp, fcu_fans[fan].loc, 64);
2105
2106         c = tmp;
2107         for (;;) {
2108                 e = strchr(c, ',');
2109                 if (e)
2110                         *e = 0;
2111                 if (strcmp(loc, c) == 0)
2112                         return 1;
2113                 if (e == NULL)
2114                         break;
2115                 c = e + 1;
2116         }
2117         return 0;
2118 }
2119
2120 static void fcu_lookup_fans(struct device_node *fcu_node)
2121 {
2122         struct device_node *np = NULL;
2123         int i;
2124
2125         /* The table is filled by default with values that are suitable
2126          * for the old machines without device-tree informations. We scan
2127          * the device-tree and override those values with whatever is
2128          * there
2129          */
2130
2131         DBG("Looking up FCU controls in device-tree...\n");
2132
2133         while ((np = of_get_next_child(fcu_node, np)) != NULL) {
2134                 int type = -1;
2135                 const char *loc;
2136                 const u32 *reg;
2137
2138                 DBG(" control: %s, type: %s\n", np->name, np->type);
2139
2140                 /* Detect control type */
2141                 if (!strcmp(np->type, "fan-rpm-control") ||
2142                     !strcmp(np->type, "fan-rpm"))
2143                         type = FCU_FAN_RPM;
2144                 if (!strcmp(np->type, "fan-pwm-control") ||
2145                     !strcmp(np->type, "fan-pwm"))
2146                         type = FCU_FAN_PWM;
2147                 /* Only care about fans for now */
2148                 if (type == -1)
2149                         continue;
2150
2151                 /* Lookup for a matching location */
2152                 loc = of_get_property(np, "location", NULL);
2153                 reg = of_get_property(np, "reg", NULL);
2154                 if (loc == NULL || reg == NULL)
2155                         continue;
2156                 DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
2157
2158                 for (i = 0; i < FCU_FAN_COUNT; i++) {
2159                         int fan_id;
2160
2161                         if (!fan_check_loc_match(loc, i))
2162                                 continue;
2163                         DBG(" location match, index: %d\n", i);
2164                         fcu_fans[i].id = FCU_FAN_ABSENT_ID;
2165                         if (type != fcu_fans[i].type) {
2166                                 printk(KERN_WARNING "therm_pm72: Fan type mismatch "
2167                                        "in device-tree for %s\n", np->full_name);
2168                                 break;
2169                         }
2170                         if (type == FCU_FAN_RPM)
2171                                 fan_id = ((*reg) - 0x10) / 2;
2172                         else
2173                                 fan_id = ((*reg) - 0x30) / 2;
2174                         if (fan_id > 7) {
2175                                 printk(KERN_WARNING "therm_pm72: Can't parse "
2176                                        "fan ID in device-tree for %s\n", np->full_name);
2177                                 break;
2178                         }
2179                         DBG(" fan id -> %d, type -> %d\n", fan_id, type);
2180                         fcu_fans[i].id = fan_id;
2181                 }
2182         }
2183
2184         /* Now dump the array */
2185         printk(KERN_INFO "Detected fan controls:\n");
2186         for (i = 0; i < FCU_FAN_COUNT; i++) {
2187                 if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
2188                         continue;
2189                 printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
2190                        fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
2191                        fcu_fans[i].id, fcu_fans[i].loc);
2192         }
2193 }
2194
2195 static int fcu_of_probe(struct of_device* dev, const struct of_device_id *match)
2196 {
2197         state = state_detached;
2198
2199         /* Lookup the fans in the device tree */
2200         fcu_lookup_fans(dev->node);
2201
2202         /* Add the driver */
2203         return i2c_add_driver(&therm_pm72_driver);
2204 }
2205
2206 static int fcu_of_remove(struct of_device* dev)
2207 {
2208         i2c_del_driver(&therm_pm72_driver);
2209
2210         return 0;
2211 }
2212
2213 static struct of_device_id fcu_match[] =
2214 {
2215         {
2216         .type           = "fcu",
2217         },
2218         {},
2219 };
2220
2221 static struct of_platform_driver fcu_of_platform_driver =
2222 {
2223         .name           = "temperature",
2224         .match_table    = fcu_match,
2225         .probe          = fcu_of_probe,
2226         .remove         = fcu_of_remove
2227 };
2228
2229 /*
2230  * Check machine type, attach to i2c controller
2231  */
2232 static int __init therm_pm72_init(void)
2233 {
2234         struct device_node *np;
2235
2236         rackmac = machine_is_compatible("RackMac3,1");
2237
2238         if (!machine_is_compatible("PowerMac7,2") &&
2239             !machine_is_compatible("PowerMac7,3") &&
2240             !rackmac)
2241                 return -ENODEV;
2242
2243         printk(KERN_INFO "PowerMac G5 Thermal control driver %s\n", VERSION);
2244
2245         np = of_find_node_by_type(NULL, "fcu");
2246         if (np == NULL) {
2247                 /* Some machines have strangely broken device-tree */
2248                 np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
2249                 if (np == NULL) {
2250                             printk(KERN_ERR "Can't find FCU in device-tree !\n");
2251                             return -ENODEV;
2252                 }
2253         }
2254         of_dev = of_platform_device_create(np, "temperature", NULL);
2255         if (of_dev == NULL) {
2256                 printk(KERN_ERR "Can't register FCU platform device !\n");
2257                 return -ENODEV;
2258         }
2259
2260         of_register_platform_driver(&fcu_of_platform_driver);
2261
2262         return 0;
2263 }
2264
2265 static void __exit therm_pm72_exit(void)
2266 {
2267         of_unregister_platform_driver(&fcu_of_platform_driver);
2268
2269         if (of_dev)
2270                 of_device_unregister(of_dev);
2271 }
2272
2273 module_init(therm_pm72_init);
2274 module_exit(therm_pm72_exit);
2275
2276 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
2277 MODULE_DESCRIPTION("Driver for Apple's PowerMac G5 thermal control");
2278 MODULE_LICENSE("GPL");
2279