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 slowing 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  *          better... 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  *      - Retrieve 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/init.h>
 118 #include <linux/spinlock.h>
 119 #include <linux/wait.h>
 120 #include <linux/reboot.h>
 121 #include <linux/kmod.h>
 122 #include <linux/i2c.h>
 123 #include <linux/kthread.h>
 124 #include <linux/mutex.h>
 125 #include <linux/of_device.h>
 126 #include <linux/of_platform.h>
 127 #include <asm/prom.h>
 128 #include <asm/machdep.h>
 129 #include <asm/io.h>
 130 #include <asm/sections.h>
 131 #include <asm/macio.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 platform_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             processor_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 struct task_struct               *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 DEFINE_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 static struct i2c_driver therm_pm72_driver;
 288
 289 /*
 290  * Utility function to create an i2c_client structure and
 291  * attach it to one of u3 adapters
 292  */
 293 static struct i2c_client *attach_i2c_chip(int id, const char *name)
 294 {
 295         struct i2c_client *clt;
 296         struct i2c_adapter *adap;
 297         struct i2c_board_info info;
 298
 299         if (id & 0x200)
 300                 adap = k2;
 301         else if (id & 0x100)
 302                 adap = u3_1;
 303         else
 304                 adap = u3_0;
 305         if (adap == NULL)
 306                 return NULL;
 307
 308         memset(&info, 0, sizeof(struct i2c_board_info));
 309         info.addr = (id >> 1) & 0x7f;
 310         strlcpy(info.type, "therm_pm72", I2C_NAME_SIZE);
 311         clt = i2c_new_device(adap, &info);
 312         if (!clt) {
 313                 printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
 314                 return NULL;
 315         }
 316
 317         /*
 318          * Let i2c-core delete that device on driver removal.
 319          * This is safe because i2c-core holds the core_lock mutex for us.
 320          */
 321         list_add_tail(&clt->detected, &therm_pm72_driver.clients);
 322         return clt;
 323 }
 324
 325 /*
 326  * Here are the i2c chip access wrappers
 327  */
 328
 329 static void initialize_adc(struct cpu_pid_state *state)
 330 {
 331         int rc;
 332         u8 buf[2];
 333
 334         /* Read ADC the configuration register and cache it. We
 335          * also make sure Config2 contains proper values, I've seen
 336          * cases where we got stale grabage in there, thus preventing
 337          * proper reading of conv. values
 338          */
 339
 340         /* Clear Config2 */
 341         buf[0] = 5;
 342         buf[1] = 0;
 343         i2c_master_send(state->monitor, buf, 2);
 344
 345         /* Read & cache Config1 */
 346         buf[0] = 1;
 347         rc = i2c_master_send(state->monitor, buf, 1);
 348         if (rc > 0) {
 349                 rc = i2c_master_recv(state->monitor, buf, 1);
 350                 if (rc > 0) {
 351                         state->adc_config = buf[0];
 352                         DBG("ADC config reg: %02x\n", state->adc_config);
 353                         /* Disable shutdown mode */
 354                         state->adc_config &= 0xfe;
 355                         buf[0] = 1;
 356                         buf[1] = state->adc_config;
 357                         rc = i2c_master_send(state->monitor, buf, 2);
 358                 }
 359         }
 360         if (rc <= 0)
 361                 printk(KERN_ERR "therm_pm72: Error reading ADC config"
 362                        " register !\n");
 363 }
 364
 365 static int read_smon_adc(struct cpu_pid_state *state, int chan)
 366 {
 367         int rc, data, tries = 0;
 368         u8 buf[2];
 369
 370         for (;;) {
 371                 /* Set channel */
 372                 buf[0] = 1;
 373                 buf[1] = (state->adc_config & 0x1f) | (chan << 5);
 374                 rc = i2c_master_send(state->monitor, buf, 2);
 375                 if (rc <= 0)
 376                         goto error;
 377                 /* Wait for conversion */
 378                 msleep(1);
 379                 /* Switch to data register */
 380                 buf[0] = 4;
 381                 rc = i2c_master_send(state->monitor, buf, 1);
 382                 if (rc <= 0)
 383                         goto error;
 384                 /* Read result */
 385                 rc = i2c_master_recv(state->monitor, buf, 2);
 386                 if (rc < 0)
 387                         goto error;
 388                 data = ((u16)buf[0]) << 8 | (u16)buf[1];
 389                 return data >> 6;
 390         error:
 391                 DBG("Error reading ADC, retrying...\n");
 392                 if (++tries > 10) {
 393                         printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
 394                         return -1;
 395                 }
 396                 msleep(10);
 397         }
 398 }
 399
 400 static int read_lm87_reg(struct i2c_client * chip, int reg)
 401 {
 402         int rc, tries = 0;
 403         u8 buf;
 404
 405         for (;;) {
 406                 /* Set address */
 407                 buf = (u8)reg;
 408                 rc = i2c_master_send(chip, &buf, 1);
 409                 if (rc <= 0)
 410                         goto error;
 411                 rc = i2c_master_recv(chip, &buf, 1);
 412                 if (rc <= 0)
 413                         goto error;
 414                 return (int)buf;
 415         error:
 416                 DBG("Error reading LM87, retrying...\n");
 417                 if (++tries > 10) {
 418                         printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
 419                         return -1;
 420                 }
 421                 msleep(10);
 422         }
 423 }
 424
 425 static int fan_read_reg(int reg, unsigned char *buf, int nb)
 426 {
 427         int tries, nr, nw;
 428
 429         buf[0] = reg;
 430         tries = 0;
 431         for (;;) {
 432                 nw = i2c_master_send(fcu, buf, 1);
 433                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
 434                         break;
 435                 msleep(10);
 436                 ++tries;
 437         }
 438         if (nw <= 0) {
 439                 printk(KERN_ERR "Failure writing address to FCU: %d", nw);
 440                 return -EIO;
 441         }
 442         tries = 0;
 443         for (;;) {
 444                 nr = i2c_master_recv(fcu, buf, nb);
 445                 if (nr > 0 || (nr < 0 && nr != -ENODEV) || tries >= 100)
 446                         break;
 447                 msleep(10);
 448                 ++tries;
 449         }
 450         if (nr <= 0)
 451                 printk(KERN_ERR "Failure reading data from FCU: %d", nw);
 452         return nr;
 453 }
 454
 455 static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
 456 {
 457         int tries, nw;
 458         unsigned char buf[16];
 459
 460         buf[0] = reg;
 461         memcpy(buf+1, ptr, nb);
 462         ++nb;
 463         tries = 0;
 464         for (;;) {
 465                 nw = i2c_master_send(fcu, buf, nb);
 466                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
 467                         break;
 468                 msleep(10);
 469                 ++tries;
 470         }
 471         if (nw < 0)
 472                 printk(KERN_ERR "Failure writing to FCU: %d", nw);
 473         return nw;
 474 }
 475
 476 static int start_fcu(void)
 477 {
 478         unsigned char buf = 0xff;
 479         int rc;
 480
 481         rc = fan_write_reg(0xe, &buf, 1);
 482         if (rc < 0)
 483                 return -EIO;
 484         rc = fan_write_reg(0x2e, &buf, 1);
 485         if (rc < 0)
 486                 return -EIO;
 487         rc = fan_read_reg(0, &buf, 1);
 488         if (rc < 0)
 489                 return -EIO;
 490         fcu_rpm_shift = (buf == 1) ? 2 : 3;
 491         printk(KERN_DEBUG "FCU Initialized, RPM fan shift is %d\n",
 492                fcu_rpm_shift);
 493
 494         return 0;
 495 }
 496
 497 static int set_rpm_fan(int fan_index, int rpm)
 498 {
 499         unsigned char buf[2];
 500         int rc, id, min, max;
 501
 502         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 503                 return -EINVAL;
 504         id = fcu_fans[fan_index].id;
 505         if (id == FCU_FAN_ABSENT_ID)
 506                 return -EINVAL;
 507
 508         min = 2400 >> fcu_rpm_shift;
 509         max = 56000 >> fcu_rpm_shift;
 510
 511         if (rpm < min)
 512                 rpm = min;
 513         else if (rpm > max)
 514                 rpm = max;
 515         buf[0] = rpm >> (8 - fcu_rpm_shift);
 516         buf[1] = rpm << fcu_rpm_shift;
 517         rc = fan_write_reg(0x10 + (id * 2), buf, 2);
 518         if (rc < 0)
 519                 return -EIO;
 520         return 0;
 521 }
 522
 523 static int get_rpm_fan(int fan_index, int programmed)
 524 {
 525         unsigned char failure;
 526         unsigned char active;
 527         unsigned char buf[2];
 528         int rc, id, reg_base;
 529
 530         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
 531                 return -EINVAL;
 532         id = fcu_fans[fan_index].id;
 533         if (id == FCU_FAN_ABSENT_ID)
 534                 return -EINVAL;
 535
 536         rc = fan_read_reg(0xb, &failure, 1);
 537         if (rc != 1)
 538                 return -EIO;
 539         if ((failure & (1 << id)) != 0)
 540                 return -EFAULT;
 541         rc = fan_read_reg(0xd, &active, 1);
 542         if (rc != 1)
 543                 return -EIO;
 544         if ((active & (1 << id)) == 0)
 545                 return -ENXIO;
 546
 547         /* Programmed value or real current speed */
 548         reg_base = programmed ? 0x10 : 0x11;
 549         rc = fan_read_reg(reg_base + (id * 2), buf, 2);
 550         if (rc != 2)
 551                 return -EIO;
 552
 553         return (buf[0] << (8 - fcu_rpm_shift)) | buf[1] >> fcu_rpm_shift;
 554 }
 555
 556 static int set_pwm_fan(int fan_index, int pwm)
 557 {
 558         unsigned char buf[2];
 559         int rc, id;
 560
 561         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
 562                 return -EINVAL;
 563         id = fcu_fans[fan_index].id;
 564         if (id == FCU_FAN_ABSENT_ID)
 565                 return -EINVAL;
 566
 567         if (pwm < 10)
 568                 pwm = 10;
 569         else if (pwm > 100)
 570                 pwm = 100;
 571         pwm = (pwm * 2559) / 1000;
 572         buf[0] = pwm;
 573         rc = fan_write_reg(0x30 + (id * 2), buf, 1);
 574         if (rc < 0)
 575                 return rc;
 576         return 0;
 577 }
 578
 579 static int get_pwm_fan(int fan_index)
 580 {
 581         unsigned char failure;
 582         unsigned char active;
 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         rc = fan_read_reg(0x2b, &failure, 1);
 593         if (rc != 1)
 594                 return -EIO;
 595         if ((failure & (1 << id)) != 0)
 596                 return -EFAULT;
 597         rc = fan_read_reg(0x2d, &active, 1);
 598         if (rc != 1)
 599                 return -EIO;
 600         if ((active & (1 << id)) == 0)
 601                 return -ENXIO;
 602
 603         /* Programmed value or real current speed */
 604         rc = fan_read_reg(0x30 + (id * 2), buf, 1);
 605         if (rc != 1)
 606                 return -EIO;
 607
 608         return (buf[0] * 1000) / 2559;
 609 }
 610
 611 static void tickle_fcu(void)
 612 {
 613         int pwm;
 614
 615         pwm = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
 616
 617         DBG("FCU Tickle, slots fan is: %d\n", pwm);
 618         if (pwm < 0)
 619                 pwm = 100;
 620
 621         if (!rackmac) {
 622                 pwm = SLOTS_FAN_DEFAULT_PWM;
 623         } else if (pwm < SLOTS_PID_OUTPUT_MIN)
 624                 pwm = SLOTS_PID_OUTPUT_MIN;
 625
 626         /* That is hopefully enough to make the FCU happy */
 627         set_pwm_fan(SLOTS_FAN_PWM_INDEX, pwm);
 628 }
 629
 630
 631 /*
 632  * Utility routine to read the CPU calibration EEPROM data
 633  * from the device-tree
 634  */
 635 static int read_eeprom(int cpu, struct mpu_data *out)
 636 {
 637         struct device_node *np;
 638         char nodename[64];
 639         const u8 *data;
 640         int len;
 641
 642         /* prom.c routine for finding a node by path is a bit brain dead
 643          * and requires exact @xxx unit numbers. This is a bit ugly but
 644          * will work for these machines
 645          */
 646         sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
 647         np = of_find_node_by_path(nodename);
 648         if (np == NULL) {
 649                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid node from device-tree\n");
 650                 return -ENODEV;
 651         }
 652         data = of_get_property(np, "cpuid", &len);
 653         if (data == NULL) {
 654                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid property from device-tree\n");
 655                 of_node_put(np);
 656                 return -ENODEV;
 657         }
 658         memcpy(out, data, sizeof(struct mpu_data));
 659         of_node_put(np);
 660
 661         return 0;
 662 }
 663
 664 static void fetch_cpu_pumps_minmax(void)
 665 {
 666         struct cpu_pid_state *state0 = &processor_state[0];
 667         struct cpu_pid_state *state1 = &processor_state[1];
 668         u16 pump_min = 0, pump_max = 0xffff;
 669         u16 tmp[4];
 670
 671         /* Try to fetch pumps min/max infos from eeprom */
 672
 673         memcpy(&tmp, &state0->mpu.processor_part_num, 8);
 674         if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
 675                 pump_min = max(pump_min, tmp[0]);
 676                 pump_max = min(pump_max, tmp[1]);
 677         }
 678         if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
 679                 pump_min = max(pump_min, tmp[2]);
 680                 pump_max = min(pump_max, tmp[3]);
 681         }
 682
 683         /* Double check the values, this _IS_ needed as the EEPROM on
 684          * some dual 2.5Ghz G5s seem, at least, to have both min & max
 685          * same to the same value ... (grrrr)
 686          */
 687         if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
 688                 pump_min = CPU_PUMP_OUTPUT_MIN;
 689                 pump_max = CPU_PUMP_OUTPUT_MAX;
 690         }
 691
 692         state0->pump_min = state1->pump_min = pump_min;
 693         state0->pump_max = state1->pump_max = pump_max;
 694 }
 695
 696 /*
 697  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 698  * pass around to the attribute functions, so we don't really have
 699  * choice but implement a bunch of them...
 700  *
 701  * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
 702  * the input twice... I accept patches :)
 703  */
 704 #define BUILD_SHOW_FUNC_FIX(name, data)                         \
 705 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 706 {                                                               \
 707         ssize_t r;                                              \
 708         mutex_lock(&driver_lock);                                       \
 709         r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));        \
 710         mutex_unlock(&driver_lock);                                     \
 711         return r;                                               \
 712 }
 713 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 714 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 715 {                                                               \
 716         return sprintf(buf, "%d", data);                        \
 717 }
 718
 719 BUILD_SHOW_FUNC_FIX(cpu0_temperature, processor_state[0].last_temp)
 720 BUILD_SHOW_FUNC_FIX(cpu0_voltage, processor_state[0].voltage)
 721 BUILD_SHOW_FUNC_FIX(cpu0_current, processor_state[0].current_a)
 722 BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, processor_state[0].rpm)
 723 BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, processor_state[0].intake_rpm)
 724
 725 BUILD_SHOW_FUNC_FIX(cpu1_temperature, processor_state[1].last_temp)
 726 BUILD_SHOW_FUNC_FIX(cpu1_voltage, processor_state[1].voltage)
 727 BUILD_SHOW_FUNC_FIX(cpu1_current, processor_state[1].current_a)
 728 BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, processor_state[1].rpm)
 729 BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, processor_state[1].intake_rpm)
 730
 731 BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
 732 BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
 733
 734 BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
 735 BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
 736
 737 BUILD_SHOW_FUNC_FIX(slots_temperature, slots_state.last_temp)
 738 BUILD_SHOW_FUNC_INT(slots_fan_pwm, slots_state.pwm)
 739
 740 BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
 741
 742 static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
 743 static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
 744 static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
 745 static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
 746 static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
 747
 748 static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
 749 static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
 750 static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
 751 static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
 752 static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
 753
 754 static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
 755 static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
 756
 757 static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
 758 static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
 759
 760 static DEVICE_ATTR(slots_temperature,S_IRUGO,show_slots_temperature,NULL);
 761 static DEVICE_ATTR(slots_fan_pwm,S_IRUGO,show_slots_fan_pwm,NULL);
 762
 763 static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
 764
 765 /*
 766  * CPUs fans control loop
 767  */
 768
 769 static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
 770 {
 771         s32 ltemp, volts, amps;
 772         int index, rc = 0;
 773
 774         /* Default (in case of error) */
 775         *temp = state->cur_temp;
 776         *power = state->cur_power;
 777
 778         if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
 779                 index = (state->index == 0) ?
 780                         CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
 781         else
 782                 index = (state->index == 0) ?
 783                         CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
 784
 785         /* Read current fan status */
 786         rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
 787         if (rc < 0) {
 788                 /* XXX What do we do now ? Nothing for now, keep old value, but
 789                  * return error upstream
 790                  */
 791                 DBG("  cpu %d, fan reading error !\n", state->index);
 792         } else {
 793                 state->rpm = rc;
 794                 DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
 795         }
 796
 797         /* Get some sensor readings and scale it */
 798         ltemp = read_smon_adc(state, 1);
 799         if (ltemp == -1) {
 800                 /* XXX What do we do now ? */
 801                 state->overtemp++;
 802                 if (rc == 0)
 803                         rc = -EIO;
 804                 DBG("  cpu %d, temp reading error !\n", state->index);
 805         } else {
 806                 /* Fixup temperature according to diode calibration
 807                  */
 808                 DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
 809                     state->index,
 810                     ltemp, state->mpu.mdiode, state->mpu.bdiode);
 811                 *temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
 812                 state->last_temp = *temp;
 813                 DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
 814         }
 815
 816         /*
 817          * Read voltage & current and calculate power
 818          */
 819         volts = read_smon_adc(state, 3);
 820         amps = read_smon_adc(state, 4);
 821
 822         /* Scale voltage and current raw sensor values according to fixed scales
 823          * obtained in Darwin and calculate power from I and V
 824          */
 825         volts *= ADC_CPU_VOLTAGE_SCALE;
 826         amps *= ADC_CPU_CURRENT_SCALE;
 827         *power = (((u64)volts) * ((u64)amps)) >> 16;
 828         state->voltage = volts;
 829         state->current_a = amps;
 830         state->last_power = *power;
 831
 832         DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
 833             state->index, FIX32TOPRINT(state->current_a),
 834             FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
 835
 836         return 0;
 837 }
 838
 839 static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
 840 {
 841         s32 power_target, integral, derivative, proportional, adj_in_target, sval;
 842         s64 integ_p, deriv_p, prop_p, sum;
 843         int i;
 844
 845         /* Calculate power target value (could be done once for all)
 846          * and convert to a 16.16 fp number
 847          */
 848         power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
 849         DBG("  power target: %d.%03d, error: %d.%03d\n",
 850             FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
 851
 852         /* Store temperature and power in history array */
 853         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 854         state->temp_history[state->cur_temp] = temp;
 855         state->cur_power = (state->cur_power + 1) % state->count_power;
 856         state->power_history[state->cur_power] = power;
 857         state->error_history[state->cur_power] = power_target - power;
 858
 859         /* If first loop, fill the history table */
 860         if (state->first) {
 861                 for (i = 0; i < (state->count_power - 1); i++) {
 862                         state->cur_power = (state->cur_power + 1) % state->count_power;
 863                         state->power_history[state->cur_power] = power;
 864                         state->error_history[state->cur_power] = power_target - power;
 865                 }
 866                 for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
 867                         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
 868                         state->temp_history[state->cur_temp] = temp;
 869                 }
 870                 state->first = 0;
 871         }
 872
 873         /* Calculate the integral term normally based on the "power" values */
 874         sum = 0;
 875         integral = 0;
 876         for (i = 0; i < state->count_power; i++)
 877                 integral += state->error_history[i];
 878         integral *= CPU_PID_INTERVAL;
 879         DBG("  integral: %08x\n", integral);
 880
 881         /* Calculate the adjusted input (sense value).
 882          *   G_r is 12.20
 883          *   integ is 16.16
 884          *   so the result is 28.36
 885          *
 886          * input target is mpu.ttarget, input max is mpu.tmax
 887          */
 888         integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
 889         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
 890         sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
 891         adj_in_target = (state->mpu.ttarget << 16);
 892         if (adj_in_target > sval)
 893                 adj_in_target = sval;
 894         DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
 895             state->mpu.ttarget);
 896
 897         /* Calculate the derivative term */
 898         derivative = state->temp_history[state->cur_temp] -
 899                 state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
 900                                     % CPU_TEMP_HISTORY_SIZE];
 901         derivative /= CPU_PID_INTERVAL;
 902         deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
 903         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
 904         sum += deriv_p;
 905
 906         /* Calculate the proportional term */
 907         proportional = temp - adj_in_target;
 908         prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
 909         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
 910         sum += prop_p;
 911
 912         /* Scale sum */
 913         sum >>= 36;
 914
 915         DBG("   sum: %d\n", (int)sum);
 916         state->rpm += (s32)sum;
 917 }
 918
 919 static void do_monitor_cpu_combined(void)
 920 {
 921         struct cpu_pid_state *state0 = &processor_state[0];
 922         struct cpu_pid_state *state1 = &processor_state[1];
 923         s32 temp0, power0, temp1, power1;
 924         s32 temp_combi, power_combi;
 925         int rc, intake, pump;
 926
 927         rc = do_read_one_cpu_values(state0, &temp0, &power0);
 928         if (rc < 0) {
 929                 /* XXX What do we do now ? */
 930         }
 931         state1->overtemp = 0;
 932         rc = do_read_one_cpu_values(state1, &temp1, &power1);
 933         if (rc < 0) {
 934                 /* XXX What do we do now ? */
 935         }
 936         if (state1->overtemp)
 937                 state0->overtemp++;
 938
 939         temp_combi = max(temp0, temp1);
 940         power_combi = max(power0, power1);
 941
 942         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
 943          * full blown immediately and try to trigger a shutdown
 944          */
 945         if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
 946                 printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
 947                        temp_combi >> 16);
 948                 state0->overtemp += CPU_MAX_OVERTEMP / 4;
 949         } else if (temp_combi > (state0->mpu.tmax << 16)) {
 950                 state0->overtemp++;
 951                 printk(KERN_WARNING "Temperature %d above max %d. overtemp %d\n",
 952                        temp_combi >> 16, state0->mpu.tmax, state0->overtemp);
 953         } else {
 954                 if (state0->overtemp)
 955                         printk(KERN_WARNING "Temperature back down to %d\n",
 956                                temp_combi >> 16);
 957                 state0->overtemp = 0;
 958         }
 959         if (state0->overtemp >= CPU_MAX_OVERTEMP)
 960                 critical_state = 1;
 961         if (state0->overtemp > 0) {
 962                 state0->rpm = state0->mpu.rmaxn_exhaust_fan;
 963                 state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
 964                 pump = state0->pump_max;
 965                 goto do_set_fans;
 966         }
 967
 968         /* Do the PID */
 969         do_cpu_pid(state0, temp_combi, power_combi);
 970
 971         /* Range check */
 972         state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
 973         state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
 974
 975         /* Calculate intake fan speed */
 976         intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
 977         intake = max(intake, (int)state0->mpu.rminn_intake_fan);
 978         intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
 979         state0->intake_rpm = intake;
 980
 981         /* Calculate pump speed */
 982         pump = (state0->rpm * state0->pump_max) /
 983                 state0->mpu.rmaxn_exhaust_fan;
 984         pump = min(pump, state0->pump_max);
 985         pump = max(pump, state0->pump_min);
 986
 987  do_set_fans:
 988         /* We copy values from state 0 to state 1 for /sysfs */
 989         state1->rpm = state0->rpm;
 990         state1->intake_rpm = state0->intake_rpm;
 991
 992         DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
 993             state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
 994
 995         /* We should check for errors, shouldn't we ? But then, what
 996          * do we do once the error occurs ? For FCU notified fan
 997          * failures (-EFAULT) we probably want to notify userland
 998          * some way...
 999          */
1000         set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1001         set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1002         set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1003         set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1004
1005         if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1006                 set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
1007         if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1008                 set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
1009 }
1010
1011 static void do_monitor_cpu_split(struct cpu_pid_state *state)
1012 {
1013         s32 temp, power;
1014         int rc, intake;
1015
1016         /* Read current fan status */
1017         rc = do_read_one_cpu_values(state, &temp, &power);
1018         if (rc < 0) {
1019                 /* XXX What do we do now ? */
1020         }
1021
1022         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1023          * full blown immediately and try to trigger a shutdown
1024          */
1025         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1026                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1027                        " (%d) !\n",
1028                        state->index, temp >> 16);
1029                 state->overtemp += CPU_MAX_OVERTEMP / 4;
1030         } else if (temp > (state->mpu.tmax << 16)) {
1031                 state->overtemp++;
1032                 printk(KERN_WARNING "CPU %d temperature %d above max %d. overtemp %d\n",
1033                        state->index, temp >> 16, state->mpu.tmax, state->overtemp);
1034         } else {
1035                 if (state->overtemp)
1036                         printk(KERN_WARNING "CPU %d temperature back down to %d\n",
1037                                state->index, temp >> 16);
1038                 state->overtemp = 0;
1039         }
1040         if (state->overtemp >= CPU_MAX_OVERTEMP)
1041                 critical_state = 1;
1042         if (state->overtemp > 0) {
1043                 state->rpm = state->mpu.rmaxn_exhaust_fan;
1044                 state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1045                 goto do_set_fans;
1046         }
1047
1048         /* Do the PID */
1049         do_cpu_pid(state, temp, power);
1050
1051         /* Range check */
1052         state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1053         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1054
1055         /* Calculate intake fan */
1056         intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1057         intake = max(intake, (int)state->mpu.rminn_intake_fan);
1058         intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1059         state->intake_rpm = intake;
1060
1061  do_set_fans:
1062         DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1063             state->index, (int)state->rpm, intake, state->overtemp);
1064
1065         /* We should check for errors, shouldn't we ? But then, what
1066          * do we do once the error occurs ? For FCU notified fan
1067          * failures (-EFAULT) we probably want to notify userland
1068          * some way...
1069          */
1070         if (state->index == 0) {
1071                 set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1072                 set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1073         } else {
1074                 set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1075                 set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1076         }
1077 }
1078
1079 static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1080 {
1081         s32 temp, power, fan_min;
1082         int rc;
1083
1084         /* Read current fan status */
1085         rc = do_read_one_cpu_values(state, &temp, &power);
1086         if (rc < 0) {
1087                 /* XXX What do we do now ? */
1088         }
1089
1090         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1091          * full blown immediately and try to trigger a shutdown
1092          */
1093         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1094                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1095                        " (%d) !\n",
1096                        state->index, temp >> 16);
1097                 state->overtemp = CPU_MAX_OVERTEMP / 4;
1098         } else if (temp > (state->mpu.tmax << 16)) {
1099                 state->overtemp++;
1100                 printk(KERN_WARNING "CPU %d temperature %d above max %d. overtemp %d\n",
1101                        state->index, temp >> 16, state->mpu.tmax, state->overtemp);
1102         } else {
1103                 if (state->overtemp)
1104                         printk(KERN_WARNING "CPU %d temperature back down to %d\n",
1105                                state->index, temp >> 16);
1106                 state->overtemp = 0;
1107         }
1108         if (state->overtemp >= CPU_MAX_OVERTEMP)
1109                 critical_state = 1;
1110         if (state->overtemp > 0) {
1111                 state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1112                 goto do_set_fans;
1113         }
1114
1115         /* Do the PID */
1116         do_cpu_pid(state, temp, power);
1117
1118         /* Check clamp from dimms */
1119         fan_min = dimm_output_clamp;
1120         fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1121
1122         DBG(" CPU min mpu = %d, min dimm = %d\n",
1123             state->mpu.rminn_intake_fan, dimm_output_clamp);
1124
1125         state->rpm = max(state->rpm, (int)fan_min);
1126         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1127         state->intake_rpm = state->rpm;
1128
1129  do_set_fans:
1130         DBG("** CPU %d RPM: %d overtemp: %d\n",
1131             state->index, (int)state->rpm, state->overtemp);
1132
1133         /* We should check for errors, shouldn't we ? But then, what
1134          * do we do once the error occurs ? For FCU notified fan
1135          * failures (-EFAULT) we probably want to notify userland
1136          * some way...
1137          */
1138         if (state->index == 0) {
1139                 set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1140                 set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1141                 set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1142         } else {
1143                 set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1144                 set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1145                 set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1146         }
1147 }
1148
1149 /*
1150  * Initialize the state structure for one CPU control loop
1151  */
1152 static int init_processor_state(struct cpu_pid_state *state, int index)
1153 {
1154         int err;
1155
1156         state->index = index;
1157         state->first = 1;
1158         state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1159         state->overtemp = 0;
1160         state->adc_config = 0x00;
1161
1162
1163         if (index == 0)
1164                 state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1165         else if (index == 1)
1166                 state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1167         if (state->monitor == NULL)
1168                 goto fail;
1169
1170         if (read_eeprom(index, &state->mpu))
1171                 goto fail;
1172
1173         state->count_power = state->mpu.tguardband;
1174         if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1175                 printk(KERN_WARNING "Warning ! too many power history slots\n");
1176                 state->count_power = CPU_POWER_HISTORY_SIZE;
1177         }
1178         DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1179
1180         if (index == 0) {
1181                 err = device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1182                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1183                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1184                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1185                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1186         } else {
1187                 err = device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1188                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1189                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1190                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1191                 err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1192         }
1193         if (err)
1194                 printk(KERN_WARNING "Failed to create some of the attribute"
1195                         "files for CPU %d\n", index);
1196
1197         return 0;
1198  fail:
1199         state->monitor = NULL;
1200
1201         return -ENODEV;
1202 }
1203
1204 /*
1205  * Dispose of the state data for one CPU control loop
1206  */
1207 static void dispose_processor_state(struct cpu_pid_state *state)
1208 {
1209         if (state->monitor == NULL)
1210                 return;
1211
1212         if (state->index == 0) {
1213                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1214                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1215                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1216                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1217                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1218         } else {
1219                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1220                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1221                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1222                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1223                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1224         }
1225
1226         state->monitor = NULL;
1227 }
1228
1229 /*
1230  * Motherboard backside & U3 heatsink fan control loop
1231  */
1232 static void do_monitor_backside(struct backside_pid_state *state)
1233 {
1234         s32 temp, integral, derivative, fan_min;
1235         s64 integ_p, deriv_p, prop_p, sum;
1236         int i, rc;
1237
1238         if (--state->ticks != 0)
1239                 return;
1240         state->ticks = backside_params.interval;
1241
1242         DBG("backside:\n");
1243
1244         /* Check fan status */
1245         rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1246         if (rc < 0) {
1247                 printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1248                 /* XXX What do we do now ? */
1249         } else
1250                 state->pwm = rc;
1251         DBG("  current pwm: %d\n", state->pwm);
1252
1253         /* Get some sensor readings */
1254         temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1255         state->last_temp = temp;
1256         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1257             FIX32TOPRINT(backside_params.input_target));
1258
1259         /* Store temperature and error in history array */
1260         state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1261         state->sample_history[state->cur_sample] = temp;
1262         state->error_history[state->cur_sample] = temp - backside_params.input_target;
1263
1264         /* If first loop, fill the history table */
1265         if (state->first) {
1266                 for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1267                         state->cur_sample = (state->cur_sample + 1) %
1268                                 BACKSIDE_PID_HISTORY_SIZE;
1269                         state->sample_history[state->cur_sample] = temp;
1270                         state->error_history[state->cur_sample] =
1271                                 temp - backside_params.input_target;
1272                 }
1273                 state->first = 0;
1274         }
1275
1276         /* Calculate the integral term */
1277         sum = 0;
1278         integral = 0;
1279         for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1280                 integral += state->error_history[i];
1281         integral *= backside_params.interval;
1282         DBG("  integral: %08x\n", integral);
1283         integ_p = ((s64)backside_params.G_r) * (s64)integral;
1284         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1285         sum += integ_p;
1286
1287         /* Calculate the derivative term */
1288         derivative = state->error_history[state->cur_sample] -
1289                 state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1290                                     % BACKSIDE_PID_HISTORY_SIZE];
1291         derivative /= backside_params.interval;
1292         deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1293         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1294         sum += deriv_p;
1295
1296         /* Calculate the proportional term */
1297         prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1298         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1299         sum += prop_p;
1300
1301         /* Scale sum */
1302         sum >>= 36;
1303
1304         DBG("   sum: %d\n", (int)sum);
1305         if (backside_params.additive)
1306                 state->pwm += (s32)sum;
1307         else
1308                 state->pwm = sum;
1309
1310         /* Check for clamp */
1311         fan_min = (dimm_output_clamp * 100) / 14000;
1312         fan_min = max(fan_min, backside_params.output_min);
1313
1314         state->pwm = max(state->pwm, fan_min);
1315         state->pwm = min(state->pwm, backside_params.output_max);
1316
1317         DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1318         set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1319 }
1320
1321 /*
1322  * Initialize the state structure for the backside fan control loop
1323  */
1324 static int init_backside_state(struct backside_pid_state *state)
1325 {
1326         struct device_node *u3;
1327         int u3h = 1; /* conservative by default */
1328         int err;
1329
1330         /*
1331          * There are different PID params for machines with U3 and machines
1332          * with U3H, pick the right ones now
1333          */
1334         u3 = of_find_node_by_path("/u3@0,f8000000");
1335         if (u3 != NULL) {
1336                 const u32 *vers = of_get_property(u3, "device-rev", NULL);
1337                 if (vers)
1338                         if (((*vers) & 0x3f) < 0x34)
1339                                 u3h = 0;
1340                 of_node_put(u3);
1341         }
1342
1343         if (rackmac) {
1344                 backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1345                 backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1346                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1347                 backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1348                 backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1349                 backside_params.G_r = BACKSIDE_PID_G_r;
1350                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1351                 backside_params.additive = 0;
1352         } else if (u3h) {
1353                 backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1354                 backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1355                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1356                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1357                 backside_params.G_p = BACKSIDE_PID_G_p;
1358                 backside_params.G_r = BACKSIDE_PID_G_r;
1359                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1360                 backside_params.additive = 1;
1361         } else {
1362                 backside_params.G_d = BACKSIDE_PID_U3_G_d;
1363                 backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1364                 backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1365                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1366                 backside_params.G_p = BACKSIDE_PID_G_p;
1367                 backside_params.G_r = BACKSIDE_PID_G_r;
1368                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1369                 backside_params.additive = 1;
1370         }
1371
1372         state->ticks = 1;
1373         state->first = 1;
1374         state->pwm = 50;
1375
1376         state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1377         if (state->monitor == NULL)
1378                 return -ENODEV;
1379
1380         err = device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1381         err |= device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1382         if (err)
1383                 printk(KERN_WARNING "Failed to create attribute file(s)"
1384                         " for backside fan\n");
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         state->monitor = NULL;
1401 }
1402
1403 /*
1404  * Drives bay fan control loop
1405  */
1406 static void do_monitor_drives(struct drives_pid_state *state)
1407 {
1408         s32 temp, integral, derivative;
1409         s64 integ_p, deriv_p, prop_p, sum;
1410         int i, rc;
1411
1412         if (--state->ticks != 0)
1413                 return;
1414         state->ticks = DRIVES_PID_INTERVAL;
1415
1416         DBG("drives:\n");
1417
1418         /* Check fan status */
1419         rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1420         if (rc < 0) {
1421                 printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1422                 /* XXX What do we do now ? */
1423         } else
1424                 state->rpm = rc;
1425         DBG("  current rpm: %d\n", state->rpm);
1426
1427         /* Get some sensor readings */
1428         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1429                                                     DS1775_TEMP)) << 8;
1430         state->last_temp = temp;
1431         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1432             FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1433
1434         /* Store temperature and error in history array */
1435         state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1436         state->sample_history[state->cur_sample] = temp;
1437         state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1438
1439         /* If first loop, fill the history table */
1440         if (state->first) {
1441                 for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1442                         state->cur_sample = (state->cur_sample + 1) %
1443                                 DRIVES_PID_HISTORY_SIZE;
1444                         state->sample_history[state->cur_sample] = temp;
1445                         state->error_history[state->cur_sample] =
1446                                 temp - DRIVES_PID_INPUT_TARGET;
1447                 }
1448                 state->first = 0;
1449         }
1450
1451         /* Calculate the integral term */
1452         sum = 0;
1453         integral = 0;
1454         for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1455                 integral += state->error_history[i];
1456         integral *= DRIVES_PID_INTERVAL;
1457         DBG("  integral: %08x\n", integral);
1458         integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1459         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1460         sum += integ_p;
1461
1462         /* Calculate the derivative term */
1463         derivative = state->error_history[state->cur_sample] -
1464                 state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1465                                     % DRIVES_PID_HISTORY_SIZE];
1466         derivative /= DRIVES_PID_INTERVAL;
1467         deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1468         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1469         sum += deriv_p;
1470
1471         /* Calculate the proportional term */
1472         prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1473         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1474         sum += prop_p;
1475
1476         /* Scale sum */
1477         sum >>= 36;
1478
1479         DBG("   sum: %d\n", (int)sum);
1480         state->rpm += (s32)sum;
1481
1482         state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1483         state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1484
1485         DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1486         set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1487 }
1488
1489 /*
1490  * Initialize the state structure for the drives bay fan control loop
1491  */
1492 static int init_drives_state(struct drives_pid_state *state)
1493 {
1494         int err;
1495
1496         state->ticks = 1;
1497         state->first = 1;
1498         state->rpm = 1000;
1499
1500         state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1501         if (state->monitor == NULL)
1502                 return -ENODEV;
1503
1504         err = device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1505         err |= device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1506         if (err)
1507                 printk(KERN_WARNING "Failed to create attribute file(s)"
1508                         " for drives bay fan\n");
1509
1510         return 0;
1511 }
1512
1513 /*
1514  * Dispose of the state data for the drives control loop
1515  */
1516 static void dispose_drives_state(struct drives_pid_state *state)
1517 {
1518         if (state->monitor == NULL)
1519                 return;
1520
1521         device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1522         device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1523
1524         state->monitor = NULL;
1525 }
1526
1527 /*
1528  * DIMMs temp control loop
1529  */
1530 static void do_monitor_dimms(struct dimm_pid_state *state)
1531 {
1532         s32 temp, integral, derivative, fan_min;
1533         s64 integ_p, deriv_p, prop_p, sum;
1534         int i;
1535
1536         if (--state->ticks != 0)
1537                 return;
1538         state->ticks = DIMM_PID_INTERVAL;
1539
1540         DBG("DIMM:\n");
1541
1542         DBG("  current value: %d\n", state->output);
1543
1544         temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1545         if (temp < 0)
1546                 return;
1547         temp <<= 16;
1548         state->last_temp = temp;
1549         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1550             FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1551
1552         /* Store temperature and error in history array */
1553         state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1554         state->sample_history[state->cur_sample] = temp;
1555         state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1556
1557         /* If first loop, fill the history table */
1558         if (state->first) {
1559                 for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1560                         state->cur_sample = (state->cur_sample + 1) %
1561                                 DIMM_PID_HISTORY_SIZE;
1562                         state->sample_history[state->cur_sample] = temp;
1563                         state->error_history[state->cur_sample] =
1564                                 temp - DIMM_PID_INPUT_TARGET;
1565                 }
1566                 state->first = 0;
1567         }
1568
1569         /* Calculate the integral term */
1570         sum = 0;
1571         integral = 0;
1572         for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1573                 integral += state->error_history[i];
1574         integral *= DIMM_PID_INTERVAL;
1575         DBG("  integral: %08x\n", integral);
1576         integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1577         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1578         sum += integ_p;
1579
1580         /* Calculate the derivative term */
1581         derivative = state->error_history[state->cur_sample] -
1582                 state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1583                                     % DIMM_PID_HISTORY_SIZE];
1584         derivative /= DIMM_PID_INTERVAL;
1585         deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1586         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1587         sum += deriv_p;
1588
1589         /* Calculate the proportional term */
1590         prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1591         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1592         sum += prop_p;
1593
1594         /* Scale sum */
1595         sum >>= 36;
1596
1597         DBG("   sum: %d\n", (int)sum);
1598         state->output = (s32)sum;
1599         state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1600         state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1601         dimm_output_clamp = state->output;
1602
1603         DBG("** DIMM clamp value: %d\n", (int)state->output);
1604
1605         /* Backside PID is only every 5 seconds, force backside fan clamping now */
1606         fan_min = (dimm_output_clamp * 100) / 14000;
1607         fan_min = max(fan_min, backside_params.output_min);
1608         if (backside_state.pwm < fan_min) {
1609                 backside_state.pwm = fan_min;
1610                 DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1611                 set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1612         }
1613 }
1614
1615 /*
1616  * Initialize the state structure for the DIMM temp control loop
1617  */
1618 static int init_dimms_state(struct dimm_pid_state *state)
1619 {
1620         state->ticks = 1;
1621         state->first = 1;
1622         state->output = 4000;
1623
1624         state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1625         if (state->monitor == NULL)
1626                 return -ENODEV;
1627
1628         if (device_create_file(&of_dev->dev, &dev_attr_dimms_temperature))
1629                 printk(KERN_WARNING "Failed to create attribute file"
1630                         " for DIMM temperature\n");
1631
1632         return 0;
1633 }
1634
1635 /*
1636  * Dispose of the state data for the DIMM control loop
1637  */
1638 static void dispose_dimms_state(struct dimm_pid_state *state)
1639 {
1640         if (state->monitor == NULL)
1641                 return;
1642
1643         device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1644
1645         state->monitor = NULL;
1646 }
1647
1648 /*
1649  * Slots fan control loop
1650  */
1651 static void do_monitor_slots(struct slots_pid_state *state)
1652 {
1653         s32 temp, integral, derivative;
1654         s64 integ_p, deriv_p, prop_p, sum;
1655         int i, rc;
1656
1657         if (--state->ticks != 0)
1658                 return;
1659         state->ticks = SLOTS_PID_INTERVAL;
1660
1661         DBG("slots:\n");
1662
1663         /* Check fan status */
1664         rc = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
1665         if (rc < 0) {
1666                 printk(KERN_WARNING "Error %d reading slots fan !\n", rc);
1667                 /* XXX What do we do now ? */
1668         } else
1669                 state->pwm = rc;
1670         DBG("  current pwm: %d\n", state->pwm);
1671
1672         /* Get some sensor readings */
1673         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1674                                                     DS1775_TEMP)) << 8;
1675         state->last_temp = temp;
1676         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1677             FIX32TOPRINT(SLOTS_PID_INPUT_TARGET));
1678
1679         /* Store temperature and error in history array */
1680         state->cur_sample = (state->cur_sample + 1) % SLOTS_PID_HISTORY_SIZE;
1681         state->sample_history[state->cur_sample] = temp;
1682         state->error_history[state->cur_sample] = temp - SLOTS_PID_INPUT_TARGET;
1683
1684         /* If first loop, fill the history table */
1685         if (state->first) {
1686                 for (i = 0; i < (SLOTS_PID_HISTORY_SIZE - 1); i++) {
1687                         state->cur_sample = (state->cur_sample + 1) %
1688                                 SLOTS_PID_HISTORY_SIZE;
1689                         state->sample_history[state->cur_sample] = temp;
1690                         state->error_history[state->cur_sample] =
1691                                 temp - SLOTS_PID_INPUT_TARGET;
1692                 }
1693                 state->first = 0;
1694         }
1695
1696         /* Calculate the integral term */
1697         sum = 0;
1698         integral = 0;
1699         for (i = 0; i < SLOTS_PID_HISTORY_SIZE; i++)
1700                 integral += state->error_history[i];
1701         integral *= SLOTS_PID_INTERVAL;
1702         DBG("  integral: %08x\n", integral);
1703         integ_p = ((s64)SLOTS_PID_G_r) * (s64)integral;
1704         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1705         sum += integ_p;
1706
1707         /* Calculate the derivative term */
1708         derivative = state->error_history[state->cur_sample] -
1709                 state->error_history[(state->cur_sample + SLOTS_PID_HISTORY_SIZE - 1)
1710                                     % SLOTS_PID_HISTORY_SIZE];
1711         derivative /= SLOTS_PID_INTERVAL;
1712         deriv_p = ((s64)SLOTS_PID_G_d) * (s64)derivative;
1713         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1714         sum += deriv_p;
1715
1716         /* Calculate the proportional term */
1717         prop_p = ((s64)SLOTS_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1718         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1719         sum += prop_p;
1720
1721         /* Scale sum */
1722         sum >>= 36;
1723
1724         DBG("   sum: %d\n", (int)sum);
1725         state->pwm = (s32)sum;
1726
1727         state->pwm = max(state->pwm, SLOTS_PID_OUTPUT_MIN);
1728         state->pwm = min(state->pwm, SLOTS_PID_OUTPUT_MAX);
1729
1730         DBG("** DRIVES PWM: %d\n", (int)state->pwm);
1731         set_pwm_fan(SLOTS_FAN_PWM_INDEX, state->pwm);
1732 }
1733
1734 /*
1735  * Initialize the state structure for the slots bay fan control loop
1736  */
1737 static int init_slots_state(struct slots_pid_state *state)
1738 {
1739         int err;
1740
1741         state->ticks = 1;
1742         state->first = 1;
1743         state->pwm = 50;
1744
1745         state->monitor = attach_i2c_chip(XSERVE_SLOTS_LM75, "slots_temp");
1746         if (state->monitor == NULL)
1747                 return -ENODEV;
1748
1749         err = device_create_file(&of_dev->dev, &dev_attr_slots_temperature);
1750         err |= device_create_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1751         if (err)
1752                 printk(KERN_WARNING "Failed to create attribute file(s)"
1753                         " for slots bay fan\n");
1754
1755         return 0;
1756 }
1757
1758 /*
1759  * Dispose of the state data for the slots control loop
1760  */
1761 static void dispose_slots_state(struct slots_pid_state *state)
1762 {
1763         if (state->monitor == NULL)
1764                 return;
1765
1766         device_remove_file(&of_dev->dev, &dev_attr_slots_temperature);
1767         device_remove_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1768
1769         state->monitor = NULL;
1770 }
1771
1772
1773 static int call_critical_overtemp(void)
1774 {
1775         char *argv[] = { critical_overtemp_path, NULL };
1776         static char *envp[] = { "HOME=/",
1777                                 "TERM=linux",
1778                                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1779                                 NULL };
1780
1781         return call_usermodehelper(critical_overtemp_path,
1782                                    argv, envp, UMH_WAIT_EXEC);
1783 }
1784
1785
1786 /*
1787  * Here's the kernel thread that calls the various control loops
1788  */
1789 static int main_control_loop(void *x)
1790 {
1791         DBG("main_control_loop started\n");
1792
1793         mutex_lock(&driver_lock);
1794
1795         if (start_fcu() < 0) {
1796                 printk(KERN_ERR "kfand: failed to start FCU\n");
1797                 mutex_unlock(&driver_lock);
1798                 goto out;
1799         }
1800
1801         /* Set the PCI fan once for now on non-RackMac */
1802         if (!rackmac)
1803                 set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1804
1805         /* Initialize ADCs */
1806         initialize_adc(&processor_state[0]);
1807         if (processor_state[1].monitor != NULL)
1808                 initialize_adc(&processor_state[1]);
1809
1810         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1811
1812         mutex_unlock(&driver_lock);
1813
1814         while (state == state_attached) {
1815                 unsigned long elapsed, start;
1816
1817                 start = jiffies;
1818
1819                 mutex_lock(&driver_lock);
1820
1821                 /* Tickle the FCU just in case */
1822                 if (--fcu_tickle_ticks < 0) {
1823                         fcu_tickle_ticks = FCU_TICKLE_TICKS;
1824                         tickle_fcu();
1825                 }
1826
1827                 /* First, we always calculate the new DIMMs state on an Xserve */
1828                 if (rackmac)
1829                         do_monitor_dimms(&dimms_state);
1830
1831                 /* Then, the CPUs */
1832                 if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1833                         do_monitor_cpu_combined();
1834                 else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1835                         do_monitor_cpu_rack(&processor_state[0]);
1836                         if (processor_state[1].monitor != NULL)
1837                                 do_monitor_cpu_rack(&processor_state[1]);
1838                         // better deal with UP
1839                 } else {
1840                         do_monitor_cpu_split(&processor_state[0]);
1841                         if (processor_state[1].monitor != NULL)
1842                                 do_monitor_cpu_split(&processor_state[1]);
1843                         // better deal with UP
1844                 }
1845                 /* Then, the rest */
1846                 do_monitor_backside(&backside_state);
1847                 if (rackmac)
1848                         do_monitor_slots(&slots_state);
1849                 else
1850                         do_monitor_drives(&drives_state);
1851                 mutex_unlock(&driver_lock);
1852
1853                 if (critical_state == 1) {
1854                         printk(KERN_WARNING "Temperature control detected a critical condition\n");
1855                         printk(KERN_WARNING "Attempting to shut down...\n");
1856                         if (call_critical_overtemp()) {
1857                                 printk(KERN_WARNING "Can't call %s, power off now!\n",
1858                                        critical_overtemp_path);
1859                                 machine_power_off();
1860                         }
1861                 }
1862                 if (critical_state > 0)
1863                         critical_state++;
1864                 if (critical_state > MAX_CRITICAL_STATE) {
1865                         printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1866                         machine_power_off();
1867                 }
1868
1869                 // FIXME: Deal with signals
1870                 elapsed = jiffies - start;
1871                 if (elapsed < HZ)
1872                         schedule_timeout_interruptible(HZ - elapsed);
1873         }
1874
1875  out:
1876         DBG("main_control_loop ended\n");
1877
1878         ctrl_task = 0;
1879         complete_and_exit(&ctrl_complete, 0);
1880 }
1881
1882 /*
1883  * Dispose the control loops when tearing down
1884  */
1885 static void dispose_control_loops(void)
1886 {
1887         dispose_processor_state(&processor_state[0]);
1888         dispose_processor_state(&processor_state[1]);
1889         dispose_backside_state(&backside_state);
1890         dispose_drives_state(&drives_state);
1891         dispose_slots_state(&slots_state);
1892         dispose_dimms_state(&dimms_state);
1893 }
1894
1895 /*
1896  * Create the control loops. U3-0 i2c bus is up, so we can now
1897  * get to the various sensors
1898  */
1899 static int create_control_loops(void)
1900 {
1901         struct device_node *np;
1902
1903         /* Count CPUs from the device-tree, we don't care how many are
1904          * actually used by Linux
1905          */
1906         cpu_count = 0;
1907         for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1908                 cpu_count++;
1909
1910         DBG("counted %d CPUs in the device-tree\n", cpu_count);
1911
1912         /* Decide the type of PID algorithm to use based on the presence of
1913          * the pumps, though that may not be the best way, that is good enough
1914          * for now
1915          */
1916         if (rackmac)
1917                 cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1918         else if (of_machine_is_compatible("PowerMac7,3")
1919             && (cpu_count > 1)
1920             && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1921             && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1922                 printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1923                 cpu_pid_type = CPU_PID_TYPE_COMBINED;
1924         } else
1925                 cpu_pid_type = CPU_PID_TYPE_SPLIT;
1926
1927         /* Create control loops for everything. If any fail, everything
1928          * fails
1929          */
1930         if (init_processor_state(&processor_state[0], 0))
1931                 goto fail;
1932         if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1933                 fetch_cpu_pumps_minmax();
1934
1935         if (cpu_count > 1 && init_processor_state(&processor_state[1], 1))
1936                 goto fail;
1937         if (init_backside_state(&backside_state))
1938                 goto fail;
1939         if (rackmac && init_dimms_state(&dimms_state))
1940                 goto fail;
1941         if (rackmac && init_slots_state(&slots_state))
1942                 goto fail;
1943         if (!rackmac && init_drives_state(&drives_state))
1944                 goto fail;
1945
1946         DBG("all control loops up !\n");
1947
1948         return 0;
1949
1950  fail:
1951         DBG("failure creating control loops, disposing\n");
1952
1953         dispose_control_loops();
1954
1955         return -ENODEV;
1956 }
1957
1958 /*
1959  * Start the control loops after everything is up, that is create
1960  * the thread that will make them run
1961  */
1962 static void start_control_loops(void)
1963 {
1964         init_completion(&ctrl_complete);
1965
1966         ctrl_task = kthread_run(main_control_loop, NULL, "kfand");
1967 }
1968
1969 /*
1970  * Stop the control loops when tearing down
1971  */
1972 static void stop_control_loops(void)
1973 {
1974         if (ctrl_task)
1975                 wait_for_completion(&ctrl_complete);
1976 }
1977
1978 /*
1979  * Attach to the i2c FCU after detecting U3-1 bus
1980  */
1981 static int attach_fcu(void)
1982 {
1983         fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1984         if (fcu == NULL)
1985                 return -ENODEV;
1986
1987         DBG("FCU attached\n");
1988
1989         return 0;
1990 }
1991
1992 /*
1993  * Detach from the i2c FCU when tearing down
1994  */
1995 static void detach_fcu(void)
1996 {
1997         fcu = NULL;
1998 }
1999
2000 /*
2001  * Attach to the i2c controller. We probe the various chips based
2002  * on the device-tree nodes and build everything for the driver to
2003  * run, we then kick the driver monitoring thread
2004  */
2005 static int therm_pm72_attach(struct i2c_adapter *adapter)
2006 {
2007         mutex_lock(&driver_lock);
2008
2009         /* Check state */
2010         if (state == state_detached)
2011                 state = state_attaching;
2012         if (state != state_attaching) {
2013                 mutex_unlock(&driver_lock);
2014                 return 0;
2015         }
2016
2017         /* Check if we are looking for one of these */
2018         if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
2019                 u3_0 = adapter;
2020                 DBG("found U3-0\n");
2021                 if (k2 || !rackmac)
2022                         if (create_control_loops())
2023                                 u3_0 = NULL;
2024         } else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
2025                 u3_1 = adapter;
2026                 DBG("found U3-1, attaching FCU\n");
2027                 if (attach_fcu())
2028                         u3_1 = NULL;
2029         } else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
2030                 k2 = adapter;
2031                 DBG("Found K2\n");
2032                 if (u3_0 && rackmac)
2033                         if (create_control_loops())
2034                                 k2 = NULL;
2035         }
2036         /* We got all we need, start control loops */
2037         if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
2038                 DBG("everything up, starting control loops\n");
2039                 state = state_attached;
2040                 start_control_loops();
2041         }
2042         mutex_unlock(&driver_lock);
2043
2044         return 0;
2045 }
2046
2047 static int therm_pm72_probe(struct i2c_client *client,
2048                             const struct i2c_device_id *id)
2049 {
2050         /* Always succeed, the real work was done in therm_pm72_attach() */
2051         return 0;
2052 }
2053
2054 /*
2055  * Called when any of the devices which participates into thermal management
2056  * is going away.
2057  */
2058 static int therm_pm72_remove(struct i2c_client *client)
2059 {
2060         struct i2c_adapter *adapter = client->adapter;
2061
2062         mutex_lock(&driver_lock);
2063
2064         if (state != state_detached)
2065                 state = state_detaching;
2066
2067         /* Stop control loops if any */
2068         DBG("stopping control loops\n");
2069         mutex_unlock(&driver_lock);
2070         stop_control_loops();
2071         mutex_lock(&driver_lock);
2072
2073         if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
2074                 DBG("lost U3-0, disposing control loops\n");
2075                 dispose_control_loops();
2076                 u3_0 = NULL;
2077         }
2078
2079         if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
2080                 DBG("lost U3-1, detaching FCU\n");
2081                 detach_fcu();
2082                 u3_1 = NULL;
2083         }
2084         if (u3_0 == NULL && u3_1 == NULL)
2085                 state = state_detached;
2086
2087         mutex_unlock(&driver_lock);
2088
2089         return 0;
2090 }
2091
2092 /*
2093  * i2c_driver structure to attach to the host i2c controller
2094  */
2095
2096 static const struct i2c_device_id therm_pm72_id[] = {
2097         /*
2098          * Fake device name, thermal management is done by several
2099          * chips but we don't need to differentiate between them at
2100          * this point.
2101          */
2102         { "therm_pm72", 0 },
2103         { }
2104 };
2105
2106 static struct i2c_driver therm_pm72_driver = {
2107         .driver = {
2108                 .name   = "therm_pm72",
2109         },
2110         .attach_adapter = therm_pm72_attach,
2111         .probe          = therm_pm72_probe,
2112         .remove         = therm_pm72_remove,
2113         .id_table       = therm_pm72_id,
2114 };
2115
2116 static int fan_check_loc_match(const char *loc, int fan)
2117 {
2118         char    tmp[64];
2119         char    *c, *e;
2120
2121         strlcpy(tmp, fcu_fans[fan].loc, 64);
2122
2123         c = tmp;
2124         for (;;) {
2125                 e = strchr(c, ',');
2126                 if (e)
2127                         *e = 0;
2128                 if (strcmp(loc, c) == 0)
2129                         return 1;
2130                 if (e == NULL)
2131                         break;
2132                 c = e + 1;
2133         }
2134         return 0;
2135 }
2136
2137 static void fcu_lookup_fans(struct device_node *fcu_node)
2138 {
2139         struct device_node *np = NULL;
2140         int i;
2141
2142         /* The table is filled by default with values that are suitable
2143          * for the old machines without device-tree informations. We scan
2144          * the device-tree and override those values with whatever is
2145          * there
2146          */
2147
2148         DBG("Looking up FCU controls in device-tree...\n");
2149
2150         while ((np = of_get_next_child(fcu_node, np)) != NULL) {
2151                 int type = -1;
2152                 const char *loc;
2153                 const u32 *reg;
2154
2155                 DBG(" control: %s, type: %s\n", np->name, np->type);
2156
2157                 /* Detect control type */
2158                 if (!strcmp(np->type, "fan-rpm-control") ||
2159                     !strcmp(np->type, "fan-rpm"))
2160                         type = FCU_FAN_RPM;
2161                 if (!strcmp(np->type, "fan-pwm-control") ||
2162                     !strcmp(np->type, "fan-pwm"))
2163                         type = FCU_FAN_PWM;
2164                 /* Only care about fans for now */
2165                 if (type == -1)
2166                         continue;
2167
2168                 /* Lookup for a matching location */
2169                 loc = of_get_property(np, "location", NULL);
2170                 reg = of_get_property(np, "reg", NULL);
2171                 if (loc == NULL || reg == NULL)
2172                         continue;
2173                 DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
2174
2175                 for (i = 0; i < FCU_FAN_COUNT; i++) {
2176                         int fan_id;
2177
2178                         if (!fan_check_loc_match(loc, i))
2179                                 continue;
2180                         DBG(" location match, index: %d\n", i);
2181                         fcu_fans[i].id = FCU_FAN_ABSENT_ID;
2182                         if (type != fcu_fans[i].type) {
2183                                 printk(KERN_WARNING "therm_pm72: Fan type mismatch "
2184                                        "in device-tree for %s\n", np->full_name);
2185                                 break;
2186                         }
2187                         if (type == FCU_FAN_RPM)
2188                                 fan_id = ((*reg) - 0x10) / 2;
2189                         else
2190                                 fan_id = ((*reg) - 0x30) / 2;
2191                         if (fan_id > 7) {
2192                                 printk(KERN_WARNING "therm_pm72: Can't parse "
2193                                        "fan ID in device-tree for %s\n", np->full_name);
2194                                 break;
2195                         }
2196                         DBG(" fan id -> %d, type -> %d\n", fan_id, type);
2197                         fcu_fans[i].id = fan_id;
2198                 }
2199         }
2200
2201         /* Now dump the array */
2202         printk(KERN_INFO "Detected fan controls:\n");
2203         for (i = 0; i < FCU_FAN_COUNT; i++) {
2204                 if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
2205                         continue;
2206                 printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
2207                        fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
2208                        fcu_fans[i].id, fcu_fans[i].loc);
2209         }
2210 }
2211
2212 static int fcu_of_probe(struct platform_device* dev)
2213 {
2214         state = state_detached;
2215         of_dev = dev;
2216
2217         dev_info(&dev->dev, "PowerMac G5 Thermal control driver %s\n", VERSION);
2218
2219         /* Lookup the fans in the device tree */
2220         fcu_lookup_fans(dev->dev.of_node);
2221
2222         /* Add the driver */
2223         return i2c_add_driver(&therm_pm72_driver);
2224 }
2225
2226 static int fcu_of_remove(struct platform_device* dev)
2227 {
2228         i2c_del_driver(&therm_pm72_driver);
2229
2230         return 0;
2231 }
2232
2233 static const struct of_device_id fcu_match[] =
2234 {
2235         {
2236         .type           = "fcu",
2237         },
2238         {},
2239 };
2240 MODULE_DEVICE_TABLE(of, fcu_match);
2241
2242 static struct platform_driver fcu_of_platform_driver =
2243 {
2244         .driver = {
2245                 .name = "temperature",
2246                 .owner = THIS_MODULE,
2247                 .of_match_table = fcu_match,
2248         },
2249         .probe          = fcu_of_probe,
2250         .remove         = fcu_of_remove
2251 };
2252
2253 /*
2254  * Check machine type, attach to i2c controller
2255  */
2256 static int __init therm_pm72_init(void)
2257 {
2258         rackmac = of_machine_is_compatible("RackMac3,1");
2259
2260         if (!of_machine_is_compatible("PowerMac7,2") &&
2261             !of_machine_is_compatible("PowerMac7,3") &&
2262             !rackmac)
2263                 return -ENODEV;
2264
2265         return platform_driver_register(&fcu_of_platform_driver);
2266 }
2267
2268 static void __exit therm_pm72_exit(void)
2269 {
2270         platform_driver_unregister(&fcu_of_platform_driver);
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