Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...
[linux-2.6] / 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  */
99
100 #include <linux/config.h>
101 #include <linux/types.h>
102 #include <linux/module.h>
103 #include <linux/errno.h>
104 #include <linux/kernel.h>
105 #include <linux/delay.h>
106 #include <linux/sched.h>
107 #include <linux/slab.h>
108 #include <linux/init.h>
109 #include <linux/spinlock.h>
110 #include <linux/smp_lock.h>
111 #include <linux/wait.h>
112 #include <linux/reboot.h>
113 #include <linux/kmod.h>
114 #include <linux/i2c.h>
115 #include <asm/prom.h>
116 #include <asm/machdep.h>
117 #include <asm/io.h>
118 #include <asm/system.h>
119 #include <asm/sections.h>
120 #include <asm/of_device.h>
121 #include <asm/macio.h>
122
123 #include "therm_pm72.h"
124
125 #define VERSION "1.2b2"
126
127 #undef DEBUG
128
129 #ifdef DEBUG
130 #define DBG(args...)    printk(args)
131 #else
132 #define DBG(args...)    do { } while(0)
133 #endif
134
135
136 /*
137  * Driver statics
138  */
139
140 static struct of_device *               of_dev;
141 static struct i2c_adapter *             u3_0;
142 static struct i2c_adapter *             u3_1;
143 static struct i2c_adapter *             k2;
144 static struct i2c_client *              fcu;
145 static struct cpu_pid_state             cpu_state[2];
146 static struct basckside_pid_params      backside_params;
147 static struct backside_pid_state        backside_state;
148 static struct drives_pid_state          drives_state;
149 static struct dimm_pid_state            dimms_state;
150 static int                              state;
151 static int                              cpu_count;
152 static int                              cpu_pid_type;
153 static pid_t                            ctrl_task;
154 static struct completion                ctrl_complete;
155 static int                              critical_state;
156 static int                              rackmac;
157 static s32                              dimm_output_clamp;
158
159 static DECLARE_MUTEX(driver_lock);
160
161 /*
162  * We have 3 types of CPU PID control. One is "split" old style control
163  * for intake & exhaust fans, the other is "combined" control for both
164  * CPUs that also deals with the pumps when present. To be "compatible"
165  * with OS X at this point, we only use "COMBINED" on the machines that
166  * are identified as having the pumps (though that identification is at
167  * least dodgy). Ultimately, we could probably switch completely to this
168  * algorithm provided we hack it to deal with the UP case
169  */
170 #define CPU_PID_TYPE_SPLIT      0
171 #define CPU_PID_TYPE_COMBINED   1
172 #define CPU_PID_TYPE_RACKMAC    2
173
174 /*
175  * This table describes all fans in the FCU. The "id" and "type" values
176  * are defaults valid for all earlier machines. Newer machines will
177  * eventually override the table content based on the device-tree
178  */
179 struct fcu_fan_table
180 {
181         char*   loc;    /* location code */
182         int     type;   /* 0 = rpm, 1 = pwm, 2 = pump */
183         int     id;     /* id or -1 */
184 };
185
186 #define FCU_FAN_RPM             0
187 #define FCU_FAN_PWM             1
188
189 #define FCU_FAN_ABSENT_ID       -1
190
191 #define FCU_FAN_COUNT           ARRAY_SIZE(fcu_fans)
192
193 struct fcu_fan_table    fcu_fans[] = {
194         [BACKSIDE_FAN_PWM_INDEX] = {
195                 .loc    = "BACKSIDE,SYS CTRLR FAN",
196                 .type   = FCU_FAN_PWM,
197                 .id     = BACKSIDE_FAN_PWM_DEFAULT_ID,
198         },
199         [DRIVES_FAN_RPM_INDEX] = {
200                 .loc    = "DRIVE BAY",
201                 .type   = FCU_FAN_RPM,
202                 .id     = DRIVES_FAN_RPM_DEFAULT_ID,
203         },
204         [SLOTS_FAN_PWM_INDEX] = {
205                 .loc    = "SLOT,PCI FAN",
206                 .type   = FCU_FAN_PWM,
207                 .id     = SLOTS_FAN_PWM_DEFAULT_ID,
208         },
209         [CPUA_INTAKE_FAN_RPM_INDEX] = {
210                 .loc    = "CPU A INTAKE",
211                 .type   = FCU_FAN_RPM,
212                 .id     = CPUA_INTAKE_FAN_RPM_DEFAULT_ID,
213         },
214         [CPUA_EXHAUST_FAN_RPM_INDEX] = {
215                 .loc    = "CPU A EXHAUST",
216                 .type   = FCU_FAN_RPM,
217                 .id     = CPUA_EXHAUST_FAN_RPM_DEFAULT_ID,
218         },
219         [CPUB_INTAKE_FAN_RPM_INDEX] = {
220                 .loc    = "CPU B INTAKE",
221                 .type   = FCU_FAN_RPM,
222                 .id     = CPUB_INTAKE_FAN_RPM_DEFAULT_ID,
223         },
224         [CPUB_EXHAUST_FAN_RPM_INDEX] = {
225                 .loc    = "CPU B EXHAUST",
226                 .type   = FCU_FAN_RPM,
227                 .id     = CPUB_EXHAUST_FAN_RPM_DEFAULT_ID,
228         },
229         /* pumps aren't present by default, have to be looked up in the
230          * device-tree
231          */
232         [CPUA_PUMP_RPM_INDEX] = {
233                 .loc    = "CPU A PUMP",
234                 .type   = FCU_FAN_RPM,          
235                 .id     = FCU_FAN_ABSENT_ID,
236         },
237         [CPUB_PUMP_RPM_INDEX] = {
238                 .loc    = "CPU B PUMP",
239                 .type   = FCU_FAN_RPM,
240                 .id     = FCU_FAN_ABSENT_ID,
241         },
242         /* Xserve fans */
243         [CPU_A1_FAN_RPM_INDEX] = {
244                 .loc    = "CPU A 1",
245                 .type   = FCU_FAN_RPM,
246                 .id     = FCU_FAN_ABSENT_ID,
247         },
248         [CPU_A2_FAN_RPM_INDEX] = {
249                 .loc    = "CPU A 2",
250                 .type   = FCU_FAN_RPM,
251                 .id     = FCU_FAN_ABSENT_ID,
252         },
253         [CPU_A3_FAN_RPM_INDEX] = {
254                 .loc    = "CPU A 3",
255                 .type   = FCU_FAN_RPM,
256                 .id     = FCU_FAN_ABSENT_ID,
257         },
258         [CPU_B1_FAN_RPM_INDEX] = {
259                 .loc    = "CPU B 1",
260                 .type   = FCU_FAN_RPM,
261                 .id     = FCU_FAN_ABSENT_ID,
262         },
263         [CPU_B2_FAN_RPM_INDEX] = {
264                 .loc    = "CPU B 2",
265                 .type   = FCU_FAN_RPM,
266                 .id     = FCU_FAN_ABSENT_ID,
267         },
268         [CPU_B3_FAN_RPM_INDEX] = {
269                 .loc    = "CPU B 3",
270                 .type   = FCU_FAN_RPM,
271                 .id     = FCU_FAN_ABSENT_ID,
272         },
273 };
274
275 /*
276  * i2c_driver structure to attach to the host i2c controller
277  */
278
279 static int therm_pm72_attach(struct i2c_adapter *adapter);
280 static int therm_pm72_detach(struct i2c_adapter *adapter);
281
282 static struct i2c_driver therm_pm72_driver =
283 {
284         .driver = {
285                 .name   = "therm_pm72",
286         },
287         .attach_adapter = therm_pm72_attach,
288         .detach_adapter = therm_pm72_detach,
289 };
290
291 /*
292  * Utility function to create an i2c_client structure and
293  * attach it to one of u3 adapters
294  */
295 static struct i2c_client *attach_i2c_chip(int id, const char *name)
296 {
297         struct i2c_client *clt;
298         struct i2c_adapter *adap;
299
300         if (id & 0x200)
301                 adap = k2;
302         else if (id & 0x100)
303                 adap = u3_1;
304         else
305                 adap = u3_0;
306         if (adap == NULL)
307                 return NULL;
308
309         clt = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
310         if (clt == NULL)
311                 return NULL;
312         memset(clt, 0, sizeof(struct i2c_client));
313
314         clt->addr = (id >> 1) & 0x7f;
315         clt->adapter = adap;
316         clt->driver = &therm_pm72_driver;
317         strncpy(clt->name, name, I2C_NAME_SIZE-1);
318
319         if (i2c_attach_client(clt)) {
320                 printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
321                 kfree(clt);
322                 return NULL;
323         }
324         return clt;
325 }
326
327 /*
328  * Utility function to get rid of the i2c_client structure
329  * (will also detach from the adapter hopepfully)
330  */
331 static void detach_i2c_chip(struct i2c_client *clt)
332 {
333         i2c_detach_client(clt);
334         kfree(clt);
335 }
336
337 /*
338  * Here are the i2c chip access wrappers
339  */
340
341 static void initialize_adc(struct cpu_pid_state *state)
342 {
343         int rc;
344         u8 buf[2];
345
346         /* Read ADC the configuration register and cache it. We
347          * also make sure Config2 contains proper values, I've seen
348          * cases where we got stale grabage in there, thus preventing
349          * proper reading of conv. values
350          */
351
352         /* Clear Config2 */
353         buf[0] = 5;
354         buf[1] = 0;
355         i2c_master_send(state->monitor, buf, 2);
356
357         /* Read & cache Config1 */
358         buf[0] = 1;
359         rc = i2c_master_send(state->monitor, buf, 1);
360         if (rc > 0) {
361                 rc = i2c_master_recv(state->monitor, buf, 1);
362                 if (rc > 0) {
363                         state->adc_config = buf[0];
364                         DBG("ADC config reg: %02x\n", state->adc_config);
365                         /* Disable shutdown mode */
366                         state->adc_config &= 0xfe;
367                         buf[0] = 1;
368                         buf[1] = state->adc_config;
369                         rc = i2c_master_send(state->monitor, buf, 2);
370                 }
371         }
372         if (rc <= 0)
373                 printk(KERN_ERR "therm_pm72: Error reading ADC config"
374                        " register !\n");
375 }
376
377 static int read_smon_adc(struct cpu_pid_state *state, int chan)
378 {
379         int rc, data, tries = 0;
380         u8 buf[2];
381
382         for (;;) {
383                 /* Set channel */
384                 buf[0] = 1;
385                 buf[1] = (state->adc_config & 0x1f) | (chan << 5);
386                 rc = i2c_master_send(state->monitor, buf, 2);
387                 if (rc <= 0)
388                         goto error;
389                 /* Wait for convertion */
390                 msleep(1);
391                 /* Switch to data register */
392                 buf[0] = 4;
393                 rc = i2c_master_send(state->monitor, buf, 1);
394                 if (rc <= 0)
395                         goto error;
396                 /* Read result */
397                 rc = i2c_master_recv(state->monitor, buf, 2);
398                 if (rc < 0)
399                         goto error;
400                 data = ((u16)buf[0]) << 8 | (u16)buf[1];
401                 return data >> 6;
402         error:
403                 DBG("Error reading ADC, retrying...\n");
404                 if (++tries > 10) {
405                         printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
406                         return -1;
407                 }
408                 msleep(10);
409         }
410 }
411
412 static int read_lm87_reg(struct i2c_client * chip, int reg)
413 {
414         int rc, tries = 0;
415         u8 buf;
416
417         for (;;) {
418                 /* Set address */
419                 buf = (u8)reg;
420                 rc = i2c_master_send(chip, &buf, 1);
421                 if (rc <= 0)
422                         goto error;
423                 rc = i2c_master_recv(chip, &buf, 1);
424                 if (rc <= 0)
425                         goto error;
426                 return (int)buf;
427         error:
428                 DBG("Error reading LM87, retrying...\n");
429                 if (++tries > 10) {
430                         printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
431                         return -1;
432                 }
433                 msleep(10);
434         }
435 }
436
437 static int fan_read_reg(int reg, unsigned char *buf, int nb)
438 {
439         int tries, nr, nw;
440
441         buf[0] = reg;
442         tries = 0;
443         for (;;) {
444                 nw = i2c_master_send(fcu, buf, 1);
445                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
446                         break;
447                 msleep(10);
448                 ++tries;
449         }
450         if (nw <= 0) {
451                 printk(KERN_ERR "Failure writing address to FCU: %d", nw);
452                 return -EIO;
453         }
454         tries = 0;
455         for (;;) {
456                 nr = i2c_master_recv(fcu, buf, nb);
457                 if (nr > 0 || (nr < 0 && nr != ENODEV) || tries >= 100)
458                         break;
459                 msleep(10);
460                 ++tries;
461         }
462         if (nr <= 0)
463                 printk(KERN_ERR "Failure reading data from FCU: %d", nw);
464         return nr;
465 }
466
467 static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
468 {
469         int tries, nw;
470         unsigned char buf[16];
471
472         buf[0] = reg;
473         memcpy(buf+1, ptr, nb);
474         ++nb;
475         tries = 0;
476         for (;;) {
477                 nw = i2c_master_send(fcu, buf, nb);
478                 if (nw > 0 || (nw < 0 && nw != EIO) || tries >= 100)
479                         break;
480                 msleep(10);
481                 ++tries;
482         }
483         if (nw < 0)
484                 printk(KERN_ERR "Failure writing to FCU: %d", nw);
485         return nw;
486 }
487
488 static int start_fcu(void)
489 {
490         unsigned char buf = 0xff;
491         int rc;
492
493         rc = fan_write_reg(0xe, &buf, 1);
494         if (rc < 0)
495                 return -EIO;
496         rc = fan_write_reg(0x2e, &buf, 1);
497         if (rc < 0)
498                 return -EIO;
499         return 0;
500 }
501
502 static int set_rpm_fan(int fan_index, int rpm)
503 {
504         unsigned char buf[2];
505         int rc, id;
506
507         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
508                 return -EINVAL;
509         id = fcu_fans[fan_index].id; 
510         if (id == FCU_FAN_ABSENT_ID)
511                 return -EINVAL;
512
513         if (rpm < 300)
514                 rpm = 300;
515         else if (rpm > 8191)
516                 rpm = 8191;
517         buf[0] = rpm >> 5;
518         buf[1] = rpm << 3;
519         rc = fan_write_reg(0x10 + (id * 2), buf, 2);
520         if (rc < 0)
521                 return -EIO;
522         return 0;
523 }
524
525 static int get_rpm_fan(int fan_index, int programmed)
526 {
527         unsigned char failure;
528         unsigned char active;
529         unsigned char buf[2];
530         int rc, id, reg_base;
531
532         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
533                 return -EINVAL;
534         id = fcu_fans[fan_index].id; 
535         if (id == FCU_FAN_ABSENT_ID)
536                 return -EINVAL;
537
538         rc = fan_read_reg(0xb, &failure, 1);
539         if (rc != 1)
540                 return -EIO;
541         if ((failure & (1 << id)) != 0)
542                 return -EFAULT;
543         rc = fan_read_reg(0xd, &active, 1);
544         if (rc != 1)
545                 return -EIO;
546         if ((active & (1 << id)) == 0)
547                 return -ENXIO;
548
549         /* Programmed value or real current speed */
550         reg_base = programmed ? 0x10 : 0x11;
551         rc = fan_read_reg(reg_base + (id * 2), buf, 2);
552         if (rc != 2)
553                 return -EIO;
554
555         return (buf[0] << 5) | buf[1] >> 3;
556 }
557
558 static int set_pwm_fan(int fan_index, int pwm)
559 {
560         unsigned char buf[2];
561         int rc, id;
562
563         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
564                 return -EINVAL;
565         id = fcu_fans[fan_index].id; 
566         if (id == FCU_FAN_ABSENT_ID)
567                 return -EINVAL;
568
569         if (pwm < 10)
570                 pwm = 10;
571         else if (pwm > 100)
572                 pwm = 100;
573         pwm = (pwm * 2559) / 1000;
574         buf[0] = pwm;
575         rc = fan_write_reg(0x30 + (id * 2), buf, 1);
576         if (rc < 0)
577                 return rc;
578         return 0;
579 }
580
581 static int get_pwm_fan(int fan_index)
582 {
583         unsigned char failure;
584         unsigned char active;
585         unsigned char buf[2];
586         int rc, id;
587
588         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
589                 return -EINVAL;
590         id = fcu_fans[fan_index].id; 
591         if (id == FCU_FAN_ABSENT_ID)
592                 return -EINVAL;
593
594         rc = fan_read_reg(0x2b, &failure, 1);
595         if (rc != 1)
596                 return -EIO;
597         if ((failure & (1 << id)) != 0)
598                 return -EFAULT;
599         rc = fan_read_reg(0x2d, &active, 1);
600         if (rc != 1)
601                 return -EIO;
602         if ((active & (1 << id)) == 0)
603                 return -ENXIO;
604
605         /* Programmed value or real current speed */
606         rc = fan_read_reg(0x30 + (id * 2), buf, 1);
607         if (rc != 1)
608                 return -EIO;
609
610         return (buf[0] * 1000) / 2559;
611 }
612
613 /*
614  * Utility routine to read the CPU calibration EEPROM data
615  * from the device-tree
616  */
617 static int read_eeprom(int cpu, struct mpu_data *out)
618 {
619         struct device_node *np;
620         char nodename[64];
621         u8 *data;
622         int len;
623
624         /* prom.c routine for finding a node by path is a bit brain dead
625          * and requires exact @xxx unit numbers. This is a bit ugly but
626          * will work for these machines
627          */
628         sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
629         np = of_find_node_by_path(nodename);
630         if (np == NULL) {
631                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid node from device-tree\n");
632                 return -ENODEV;
633         }
634         data = (u8 *)get_property(np, "cpuid", &len);
635         if (data == NULL) {
636                 printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid property from device-tree\n");
637                 of_node_put(np);
638                 return -ENODEV;
639         }
640         memcpy(out, data, sizeof(struct mpu_data));
641         of_node_put(np);
642         
643         return 0;
644 }
645
646 static void fetch_cpu_pumps_minmax(void)
647 {
648         struct cpu_pid_state *state0 = &cpu_state[0];
649         struct cpu_pid_state *state1 = &cpu_state[1];
650         u16 pump_min = 0, pump_max = 0xffff;
651         u16 tmp[4];
652
653         /* Try to fetch pumps min/max infos from eeprom */
654
655         memcpy(&tmp, &state0->mpu.processor_part_num, 8);
656         if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
657                 pump_min = max(pump_min, tmp[0]);
658                 pump_max = min(pump_max, tmp[1]);
659         }
660         if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
661                 pump_min = max(pump_min, tmp[2]);
662                 pump_max = min(pump_max, tmp[3]);
663         }
664
665         /* Double check the values, this _IS_ needed as the EEPROM on
666          * some dual 2.5Ghz G5s seem, at least, to have both min & max
667          * same to the same value ... (grrrr)
668          */
669         if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
670                 pump_min = CPU_PUMP_OUTPUT_MIN;
671                 pump_max = CPU_PUMP_OUTPUT_MAX;
672         }
673
674         state0->pump_min = state1->pump_min = pump_min;
675         state0->pump_max = state1->pump_max = pump_max;
676 }
677
678 /* 
679  * Now, unfortunately, sysfs doesn't give us a nice void * we could
680  * pass around to the attribute functions, so we don't really have
681  * choice but implement a bunch of them...
682  *
683  * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
684  * the input twice... I accept patches :)
685  */
686 #define BUILD_SHOW_FUNC_FIX(name, data)                         \
687 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
688 {                                                               \
689         ssize_t r;                                              \
690         down(&driver_lock);                                     \
691         r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));        \
692         up(&driver_lock);                                       \
693         return r;                                               \
694 }
695 #define BUILD_SHOW_FUNC_INT(name, data)                         \
696 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
697 {                                                               \
698         return sprintf(buf, "%d", data);                        \
699 }
700
701 BUILD_SHOW_FUNC_FIX(cpu0_temperature, cpu_state[0].last_temp)
702 BUILD_SHOW_FUNC_FIX(cpu0_voltage, cpu_state[0].voltage)
703 BUILD_SHOW_FUNC_FIX(cpu0_current, cpu_state[0].current_a)
704 BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, cpu_state[0].rpm)
705 BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, cpu_state[0].intake_rpm)
706
707 BUILD_SHOW_FUNC_FIX(cpu1_temperature, cpu_state[1].last_temp)
708 BUILD_SHOW_FUNC_FIX(cpu1_voltage, cpu_state[1].voltage)
709 BUILD_SHOW_FUNC_FIX(cpu1_current, cpu_state[1].current_a)
710 BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, cpu_state[1].rpm)
711 BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, cpu_state[1].intake_rpm)
712
713 BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
714 BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
715
716 BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
717 BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
718
719 BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
720
721 static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
722 static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
723 static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
724 static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
725 static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
726
727 static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
728 static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
729 static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
730 static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
731 static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
732
733 static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
734 static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
735
736 static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
737 static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
738
739 static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
740
741 /*
742  * CPUs fans control loop
743  */
744
745 static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
746 {
747         s32 ltemp, volts, amps;
748         int index, rc = 0;
749
750         /* Default (in case of error) */
751         *temp = state->cur_temp;
752         *power = state->cur_power;
753
754         if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
755                 index = (state->index == 0) ?
756                         CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
757         else
758                 index = (state->index == 0) ?
759                         CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
760
761         /* Read current fan status */
762         rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
763         if (rc < 0) {
764                 /* XXX What do we do now ? Nothing for now, keep old value, but
765                  * return error upstream
766                  */
767                 DBG("  cpu %d, fan reading error !\n", state->index);
768         } else {
769                 state->rpm = rc;
770                 DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
771         }
772
773         /* Get some sensor readings and scale it */
774         ltemp = read_smon_adc(state, 1);
775         if (ltemp == -1) {
776                 /* XXX What do we do now ? */
777                 state->overtemp++;
778                 if (rc == 0)
779                         rc = -EIO;
780                 DBG("  cpu %d, temp reading error !\n", state->index);
781         } else {
782                 /* Fixup temperature according to diode calibration
783                  */
784                 DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
785                     state->index,
786                     ltemp, state->mpu.mdiode, state->mpu.bdiode);
787                 *temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
788                 state->last_temp = *temp;
789                 DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
790         }
791
792         /*
793          * Read voltage & current and calculate power
794          */
795         volts = read_smon_adc(state, 3);
796         amps = read_smon_adc(state, 4);
797
798         /* Scale voltage and current raw sensor values according to fixed scales
799          * obtained in Darwin and calculate power from I and V
800          */
801         volts *= ADC_CPU_VOLTAGE_SCALE;
802         amps *= ADC_CPU_CURRENT_SCALE;
803         *power = (((u64)volts) * ((u64)amps)) >> 16;
804         state->voltage = volts;
805         state->current_a = amps;
806         state->last_power = *power;
807
808         DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
809             state->index, FIX32TOPRINT(state->current_a),
810             FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
811
812         return 0;
813 }
814
815 static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
816 {
817         s32 power_target, integral, derivative, proportional, adj_in_target, sval;
818         s64 integ_p, deriv_p, prop_p, sum; 
819         int i;
820
821         /* Calculate power target value (could be done once for all)
822          * and convert to a 16.16 fp number
823          */
824         power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
825         DBG("  power target: %d.%03d, error: %d.%03d\n",
826             FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
827
828         /* Store temperature and power in history array */
829         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
830         state->temp_history[state->cur_temp] = temp;
831         state->cur_power = (state->cur_power + 1) % state->count_power;
832         state->power_history[state->cur_power] = power;
833         state->error_history[state->cur_power] = power_target - power;
834         
835         /* If first loop, fill the history table */
836         if (state->first) {
837                 for (i = 0; i < (state->count_power - 1); i++) {
838                         state->cur_power = (state->cur_power + 1) % state->count_power;
839                         state->power_history[state->cur_power] = power;
840                         state->error_history[state->cur_power] = power_target - power;
841                 }
842                 for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
843                         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
844                         state->temp_history[state->cur_temp] = temp;                    
845                 }
846                 state->first = 0;
847         }
848
849         /* Calculate the integral term normally based on the "power" values */
850         sum = 0;
851         integral = 0;
852         for (i = 0; i < state->count_power; i++)
853                 integral += state->error_history[i];
854         integral *= CPU_PID_INTERVAL;
855         DBG("  integral: %08x\n", integral);
856
857         /* Calculate the adjusted input (sense value).
858          *   G_r is 12.20
859          *   integ is 16.16
860          *   so the result is 28.36
861          *
862          * input target is mpu.ttarget, input max is mpu.tmax
863          */
864         integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
865         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
866         sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
867         adj_in_target = (state->mpu.ttarget << 16);
868         if (adj_in_target > sval)
869                 adj_in_target = sval;
870         DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
871             state->mpu.ttarget);
872
873         /* Calculate the derivative term */
874         derivative = state->temp_history[state->cur_temp] -
875                 state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
876                                     % CPU_TEMP_HISTORY_SIZE];
877         derivative /= CPU_PID_INTERVAL;
878         deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
879         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
880         sum += deriv_p;
881
882         /* Calculate the proportional term */
883         proportional = temp - adj_in_target;
884         prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
885         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
886         sum += prop_p;
887
888         /* Scale sum */
889         sum >>= 36;
890
891         DBG("   sum: %d\n", (int)sum);
892         state->rpm += (s32)sum;
893 }
894
895 static void do_monitor_cpu_combined(void)
896 {
897         struct cpu_pid_state *state0 = &cpu_state[0];
898         struct cpu_pid_state *state1 = &cpu_state[1];
899         s32 temp0, power0, temp1, power1;
900         s32 temp_combi, power_combi;
901         int rc, intake, pump;
902
903         rc = do_read_one_cpu_values(state0, &temp0, &power0);
904         if (rc < 0) {
905                 /* XXX What do we do now ? */
906         }
907         state1->overtemp = 0;
908         rc = do_read_one_cpu_values(state1, &temp1, &power1);
909         if (rc < 0) {
910                 /* XXX What do we do now ? */
911         }
912         if (state1->overtemp)
913                 state0->overtemp++;
914
915         temp_combi = max(temp0, temp1);
916         power_combi = max(power0, power1);
917
918         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
919          * full blown immediately and try to trigger a shutdown
920          */
921         if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
922                 printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
923                        temp_combi >> 16);
924                 state0->overtemp += CPU_MAX_OVERTEMP / 4;
925         } else if (temp_combi > (state0->mpu.tmax << 16))
926                 state0->overtemp++;
927         else
928                 state0->overtemp = 0;
929         if (state0->overtemp >= CPU_MAX_OVERTEMP)
930                 critical_state = 1;
931         if (state0->overtemp > 0) {
932                 state0->rpm = state0->mpu.rmaxn_exhaust_fan;
933                 state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
934                 pump = state0->pump_max;
935                 goto do_set_fans;
936         }
937
938         /* Do the PID */
939         do_cpu_pid(state0, temp_combi, power_combi);
940
941         /* Range check */
942         state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
943         state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
944
945         /* Calculate intake fan speed */
946         intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
947         intake = max(intake, (int)state0->mpu.rminn_intake_fan);
948         intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
949         state0->intake_rpm = intake;
950
951         /* Calculate pump speed */
952         pump = (state0->rpm * state0->pump_max) /
953                 state0->mpu.rmaxn_exhaust_fan;
954         pump = min(pump, state0->pump_max);
955         pump = max(pump, state0->pump_min);
956         
957  do_set_fans:
958         /* We copy values from state 0 to state 1 for /sysfs */
959         state1->rpm = state0->rpm;
960         state1->intake_rpm = state0->intake_rpm;
961
962         DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
963             state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
964
965         /* We should check for errors, shouldn't we ? But then, what
966          * do we do once the error occurs ? For FCU notified fan
967          * failures (-EFAULT) we probably want to notify userland
968          * some way...
969          */
970         set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
971         set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
972         set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
973         set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
974
975         if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
976                 set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
977         if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
978                 set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
979 }
980
981 static void do_monitor_cpu_split(struct cpu_pid_state *state)
982 {
983         s32 temp, power;
984         int rc, intake;
985
986         /* Read current fan status */
987         rc = do_read_one_cpu_values(state, &temp, &power);
988         if (rc < 0) {
989                 /* XXX What do we do now ? */
990         }
991
992         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
993          * full blown immediately and try to trigger a shutdown
994          */
995         if (temp >= ((state->mpu.tmax + 8) << 16)) {
996                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
997                        " (%d) !\n",
998                        state->index, temp >> 16);
999                 state->overtemp += CPU_MAX_OVERTEMP / 4;
1000         } else if (temp > (state->mpu.tmax << 16))
1001                 state->overtemp++;
1002         else
1003                 state->overtemp = 0;
1004         if (state->overtemp >= CPU_MAX_OVERTEMP)
1005                 critical_state = 1;
1006         if (state->overtemp > 0) {
1007                 state->rpm = state->mpu.rmaxn_exhaust_fan;
1008                 state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1009                 goto do_set_fans;
1010         }
1011
1012         /* Do the PID */
1013         do_cpu_pid(state, temp, power);
1014
1015         /* Range check */
1016         state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1017         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1018
1019         /* Calculate intake fan */
1020         intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1021         intake = max(intake, (int)state->mpu.rminn_intake_fan);
1022         intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1023         state->intake_rpm = intake;
1024
1025  do_set_fans:
1026         DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1027             state->index, (int)state->rpm, intake, state->overtemp);
1028
1029         /* We should check for errors, shouldn't we ? But then, what
1030          * do we do once the error occurs ? For FCU notified fan
1031          * failures (-EFAULT) we probably want to notify userland
1032          * some way...
1033          */
1034         if (state->index == 0) {
1035                 set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1036                 set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1037         } else {
1038                 set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1039                 set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1040         }
1041 }
1042
1043 static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1044 {
1045         s32 temp, power, fan_min;
1046         int rc;
1047
1048         /* Read current fan status */
1049         rc = do_read_one_cpu_values(state, &temp, &power);
1050         if (rc < 0) {
1051                 /* XXX What do we do now ? */
1052         }
1053
1054         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1055          * full blown immediately and try to trigger a shutdown
1056          */
1057         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1058                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1059                        " (%d) !\n",
1060                        state->index, temp >> 16);
1061                 state->overtemp = CPU_MAX_OVERTEMP / 4;
1062         } else if (temp > (state->mpu.tmax << 16))
1063                 state->overtemp++;
1064         else
1065                 state->overtemp = 0;
1066         if (state->overtemp >= CPU_MAX_OVERTEMP)
1067                 critical_state = 1;
1068         if (state->overtemp > 0) {
1069                 state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1070                 goto do_set_fans;
1071         }
1072
1073         /* Do the PID */
1074         do_cpu_pid(state, temp, power);
1075
1076         /* Check clamp from dimms */
1077         fan_min = dimm_output_clamp;
1078         fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1079
1080         state->rpm = max(state->rpm, (int)fan_min);
1081         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1082         state->intake_rpm = state->rpm;
1083
1084  do_set_fans:
1085         DBG("** CPU %d RPM: %d overtemp: %d\n",
1086             state->index, (int)state->rpm, state->overtemp);
1087
1088         /* We should check for errors, shouldn't we ? But then, what
1089          * do we do once the error occurs ? For FCU notified fan
1090          * failures (-EFAULT) we probably want to notify userland
1091          * some way...
1092          */
1093         if (state->index == 0) {
1094                 set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1095                 set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1096                 set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1097         } else {
1098                 set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1099                 set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1100                 set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1101         }
1102 }
1103
1104 /*
1105  * Initialize the state structure for one CPU control loop
1106  */
1107 static int init_cpu_state(struct cpu_pid_state *state, int index)
1108 {
1109         state->index = index;
1110         state->first = 1;
1111         state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1112         state->overtemp = 0;
1113         state->adc_config = 0x00;
1114
1115
1116         if (index == 0)
1117                 state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1118         else if (index == 1)
1119                 state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1120         if (state->monitor == NULL)
1121                 goto fail;
1122
1123         if (read_eeprom(index, &state->mpu))
1124                 goto fail;
1125
1126         state->count_power = state->mpu.tguardband;
1127         if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1128                 printk(KERN_WARNING "Warning ! too many power history slots\n");
1129                 state->count_power = CPU_POWER_HISTORY_SIZE;
1130         }
1131         DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1132
1133         if (index == 0) {
1134                 device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1135                 device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1136                 device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1137                 device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1138                 device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1139         } else {
1140                 device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1141                 device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1142                 device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1143                 device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1144                 device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1145         }
1146
1147         return 0;
1148  fail:
1149         if (state->monitor)
1150                 detach_i2c_chip(state->monitor);
1151         state->monitor = NULL;
1152         
1153         return -ENODEV;
1154 }
1155
1156 /*
1157  * Dispose of the state data for one CPU control loop
1158  */
1159 static void dispose_cpu_state(struct cpu_pid_state *state)
1160 {
1161         if (state->monitor == NULL)
1162                 return;
1163
1164         if (state->index == 0) {
1165                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1166                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1167                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1168                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1169                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1170         } else {
1171                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1172                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1173                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1174                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1175                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1176         }
1177
1178         detach_i2c_chip(state->monitor);
1179         state->monitor = NULL;
1180 }
1181
1182 /*
1183  * Motherboard backside & U3 heatsink fan control loop
1184  */
1185 static void do_monitor_backside(struct backside_pid_state *state)
1186 {
1187         s32 temp, integral, derivative, fan_min;
1188         s64 integ_p, deriv_p, prop_p, sum; 
1189         int i, rc;
1190
1191         if (--state->ticks != 0)
1192                 return;
1193         state->ticks = backside_params.interval;
1194
1195         DBG("backside:\n");
1196
1197         /* Check fan status */
1198         rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1199         if (rc < 0) {
1200                 printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1201                 /* XXX What do we do now ? */
1202         } else
1203                 state->pwm = rc;
1204         DBG("  current pwm: %d\n", state->pwm);
1205
1206         /* Get some sensor readings */
1207         temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1208         state->last_temp = temp;
1209         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1210             FIX32TOPRINT(backside_params.input_target));
1211
1212         /* Store temperature and error in history array */
1213         state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1214         state->sample_history[state->cur_sample] = temp;
1215         state->error_history[state->cur_sample] = temp - backside_params.input_target;
1216         
1217         /* If first loop, fill the history table */
1218         if (state->first) {
1219                 for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1220                         state->cur_sample = (state->cur_sample + 1) %
1221                                 BACKSIDE_PID_HISTORY_SIZE;
1222                         state->sample_history[state->cur_sample] = temp;
1223                         state->error_history[state->cur_sample] =
1224                                 temp - backside_params.input_target;
1225                 }
1226                 state->first = 0;
1227         }
1228
1229         /* Calculate the integral term */
1230         sum = 0;
1231         integral = 0;
1232         for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1233                 integral += state->error_history[i];
1234         integral *= backside_params.interval;
1235         DBG("  integral: %08x\n", integral);
1236         integ_p = ((s64)backside_params.G_r) * (s64)integral;
1237         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1238         sum += integ_p;
1239
1240         /* Calculate the derivative term */
1241         derivative = state->error_history[state->cur_sample] -
1242                 state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1243                                     % BACKSIDE_PID_HISTORY_SIZE];
1244         derivative /= backside_params.interval;
1245         deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1246         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1247         sum += deriv_p;
1248
1249         /* Calculate the proportional term */
1250         prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1251         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1252         sum += prop_p;
1253
1254         /* Scale sum */
1255         sum >>= 36;
1256
1257         DBG("   sum: %d\n", (int)sum);
1258         if (backside_params.additive)
1259                 state->pwm += (s32)sum;
1260         else
1261                 state->pwm = sum;
1262
1263         /* Check for clamp */
1264         fan_min = (dimm_output_clamp * 100) / 14000;
1265         fan_min = max(fan_min, backside_params.output_min);
1266
1267         state->pwm = max(state->pwm, fan_min);
1268         state->pwm = min(state->pwm, backside_params.output_max);
1269
1270         DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1271         set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1272 }
1273
1274 /*
1275  * Initialize the state structure for the backside fan control loop
1276  */
1277 static int init_backside_state(struct backside_pid_state *state)
1278 {
1279         struct device_node *u3;
1280         int u3h = 1; /* conservative by default */
1281
1282         /*
1283          * There are different PID params for machines with U3 and machines
1284          * with U3H, pick the right ones now
1285          */
1286         u3 = of_find_node_by_path("/u3@0,f8000000");
1287         if (u3 != NULL) {
1288                 u32 *vers = (u32 *)get_property(u3, "device-rev", NULL);
1289                 if (vers)
1290                         if (((*vers) & 0x3f) < 0x34)
1291                                 u3h = 0;
1292                 of_node_put(u3);
1293         }
1294
1295         if (rackmac) {
1296                 backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1297                 backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1298                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1299                 backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1300                 backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1301                 backside_params.G_r = BACKSIDE_PID_G_r;
1302                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1303                 backside_params.additive = 0;
1304         } else if (u3h) {
1305                 backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1306                 backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1307                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1308                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1309                 backside_params.G_p = BACKSIDE_PID_G_p;
1310                 backside_params.G_r = BACKSIDE_PID_G_r;
1311                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1312                 backside_params.additive = 1;
1313         } else {
1314                 backside_params.G_d = BACKSIDE_PID_U3_G_d;
1315                 backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1316                 backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1317                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1318                 backside_params.G_p = BACKSIDE_PID_G_p;
1319                 backside_params.G_r = BACKSIDE_PID_G_r;
1320                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1321                 backside_params.additive = 1;
1322         }
1323
1324         state->ticks = 1;
1325         state->first = 1;
1326         state->pwm = 50;
1327
1328         state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1329         if (state->monitor == NULL)
1330                 return -ENODEV;
1331
1332         device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1333         device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1334
1335         return 0;
1336 }
1337
1338 /*
1339  * Dispose of the state data for the backside control loop
1340  */
1341 static void dispose_backside_state(struct backside_pid_state *state)
1342 {
1343         if (state->monitor == NULL)
1344                 return;
1345
1346         device_remove_file(&of_dev->dev, &dev_attr_backside_temperature);
1347         device_remove_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1348
1349         detach_i2c_chip(state->monitor);
1350         state->monitor = NULL;
1351 }
1352  
1353 /*
1354  * Drives bay fan control loop
1355  */
1356 static void do_monitor_drives(struct drives_pid_state *state)
1357 {
1358         s32 temp, integral, derivative;
1359         s64 integ_p, deriv_p, prop_p, sum; 
1360         int i, rc;
1361
1362         if (--state->ticks != 0)
1363                 return;
1364         state->ticks = DRIVES_PID_INTERVAL;
1365
1366         DBG("drives:\n");
1367
1368         /* Check fan status */
1369         rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1370         if (rc < 0) {
1371                 printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1372                 /* XXX What do we do now ? */
1373         } else
1374                 state->rpm = rc;
1375         DBG("  current rpm: %d\n", state->rpm);
1376
1377         /* Get some sensor readings */
1378         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor, DS1775_TEMP)) << 8;
1379         state->last_temp = temp;
1380         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1381             FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1382
1383         /* Store temperature and error in history array */
1384         state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1385         state->sample_history[state->cur_sample] = temp;
1386         state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1387         
1388         /* If first loop, fill the history table */
1389         if (state->first) {
1390                 for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1391                         state->cur_sample = (state->cur_sample + 1) %
1392                                 DRIVES_PID_HISTORY_SIZE;
1393                         state->sample_history[state->cur_sample] = temp;
1394                         state->error_history[state->cur_sample] =
1395                                 temp - DRIVES_PID_INPUT_TARGET;
1396                 }
1397                 state->first = 0;
1398         }
1399
1400         /* Calculate the integral term */
1401         sum = 0;
1402         integral = 0;
1403         for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1404                 integral += state->error_history[i];
1405         integral *= DRIVES_PID_INTERVAL;
1406         DBG("  integral: %08x\n", integral);
1407         integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1408         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1409         sum += integ_p;
1410
1411         /* Calculate the derivative term */
1412         derivative = state->error_history[state->cur_sample] -
1413                 state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1414                                     % DRIVES_PID_HISTORY_SIZE];
1415         derivative /= DRIVES_PID_INTERVAL;
1416         deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1417         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1418         sum += deriv_p;
1419
1420         /* Calculate the proportional term */
1421         prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1422         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1423         sum += prop_p;
1424
1425         /* Scale sum */
1426         sum >>= 36;
1427
1428         DBG("   sum: %d\n", (int)sum);
1429         state->rpm += (s32)sum;
1430
1431         state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1432         state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1433
1434         DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1435         set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1436 }
1437
1438 /*
1439  * Initialize the state structure for the drives bay fan control loop
1440  */
1441 static int init_drives_state(struct drives_pid_state *state)
1442 {
1443         state->ticks = 1;
1444         state->first = 1;
1445         state->rpm = 1000;
1446
1447         state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1448         if (state->monitor == NULL)
1449                 return -ENODEV;
1450
1451         device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1452         device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1453
1454         return 0;
1455 }
1456
1457 /*
1458  * Dispose of the state data for the drives control loop
1459  */
1460 static void dispose_drives_state(struct drives_pid_state *state)
1461 {
1462         if (state->monitor == NULL)
1463                 return;
1464
1465         device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1466         device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1467
1468         detach_i2c_chip(state->monitor);
1469         state->monitor = NULL;
1470 }
1471
1472 /*
1473  * DIMMs temp control loop
1474  */
1475 static void do_monitor_dimms(struct dimm_pid_state *state)
1476 {
1477         s32 temp, integral, derivative, fan_min;
1478         s64 integ_p, deriv_p, prop_p, sum;
1479         int i;
1480
1481         if (--state->ticks != 0)
1482                 return;
1483         state->ticks = DIMM_PID_INTERVAL;
1484
1485         DBG("DIMM:\n");
1486
1487         DBG("  current value: %d\n", state->output);
1488
1489         temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1490         if (temp < 0)
1491                 return;
1492         temp <<= 16;
1493         state->last_temp = temp;
1494         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1495             FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1496
1497         /* Store temperature and error in history array */
1498         state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1499         state->sample_history[state->cur_sample] = temp;
1500         state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1501
1502         /* If first loop, fill the history table */
1503         if (state->first) {
1504                 for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1505                         state->cur_sample = (state->cur_sample + 1) %
1506                                 DIMM_PID_HISTORY_SIZE;
1507                         state->sample_history[state->cur_sample] = temp;
1508                         state->error_history[state->cur_sample] =
1509                                 temp - DIMM_PID_INPUT_TARGET;
1510                 }
1511                 state->first = 0;
1512         }
1513
1514         /* Calculate the integral term */
1515         sum = 0;
1516         integral = 0;
1517         for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1518                 integral += state->error_history[i];
1519         integral *= DIMM_PID_INTERVAL;
1520         DBG("  integral: %08x\n", integral);
1521         integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1522         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1523         sum += integ_p;
1524
1525         /* Calculate the derivative term */
1526         derivative = state->error_history[state->cur_sample] -
1527                 state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1528                                     % DIMM_PID_HISTORY_SIZE];
1529         derivative /= DIMM_PID_INTERVAL;
1530         deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1531         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1532         sum += deriv_p;
1533
1534         /* Calculate the proportional term */
1535         prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1536         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1537         sum += prop_p;
1538
1539         /* Scale sum */
1540         sum >>= 36;
1541
1542         DBG("   sum: %d\n", (int)sum);
1543         state->output = (s32)sum;
1544         state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1545         state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1546         dimm_output_clamp = state->output;
1547
1548         DBG("** DIMM clamp value: %d\n", (int)state->output);
1549
1550         /* Backside PID is only every 5 seconds, force backside fan clamping now */
1551         fan_min = (dimm_output_clamp * 100) / 14000;
1552         fan_min = max(fan_min, backside_params.output_min);
1553         if (backside_state.pwm < fan_min) {
1554                 backside_state.pwm = fan_min;
1555                 DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1556                 set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1557         }
1558 }
1559
1560 /*
1561  * Initialize the state structure for the DIMM temp control loop
1562  */
1563 static int init_dimms_state(struct dimm_pid_state *state)
1564 {
1565         state->ticks = 1;
1566         state->first = 1;
1567         state->output = 4000;
1568
1569         state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1570         if (state->monitor == NULL)
1571                 return -ENODEV;
1572
1573         device_create_file(&of_dev->dev, &dev_attr_dimms_temperature);
1574
1575         return 0;
1576 }
1577
1578 /*
1579  * Dispose of the state data for the drives control loop
1580  */
1581 static void dispose_dimms_state(struct dimm_pid_state *state)
1582 {
1583         if (state->monitor == NULL)
1584                 return;
1585
1586         device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1587
1588         detach_i2c_chip(state->monitor);
1589         state->monitor = NULL;
1590 }
1591
1592 static int call_critical_overtemp(void)
1593 {
1594         char *argv[] = { critical_overtemp_path, NULL };
1595         static char *envp[] = { "HOME=/",
1596                                 "TERM=linux",
1597                                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1598                                 NULL };
1599
1600         return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
1601 }
1602
1603
1604 /*
1605  * Here's the kernel thread that calls the various control loops
1606  */
1607 static int main_control_loop(void *x)
1608 {
1609         daemonize("kfand");
1610
1611         DBG("main_control_loop started\n");
1612
1613         down(&driver_lock);
1614
1615         if (start_fcu() < 0) {
1616                 printk(KERN_ERR "kfand: failed to start FCU\n");
1617                 up(&driver_lock);
1618                 goto out;
1619         }
1620
1621         /* Set the PCI fan once for now */
1622         set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1623
1624         /* Initialize ADCs */
1625         initialize_adc(&cpu_state[0]);
1626         if (cpu_state[1].monitor != NULL)
1627                 initialize_adc(&cpu_state[1]);
1628
1629         up(&driver_lock);
1630
1631         while (state == state_attached) {
1632                 unsigned long elapsed, start;
1633
1634                 start = jiffies;
1635
1636                 down(&driver_lock);
1637
1638                 /* First, we always calculate the new DIMMs state on an Xserve */
1639                 if (rackmac)
1640                         do_monitor_dimms(&dimms_state);
1641
1642                 /* Then, the CPUs */
1643                 if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1644                         do_monitor_cpu_combined();
1645                 else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1646                         do_monitor_cpu_rack(&cpu_state[0]);
1647                         if (cpu_state[1].monitor != NULL)
1648                                 do_monitor_cpu_rack(&cpu_state[1]);
1649                         // better deal with UP
1650                 } else {
1651                         do_monitor_cpu_split(&cpu_state[0]);
1652                         if (cpu_state[1].monitor != NULL)
1653                                 do_monitor_cpu_split(&cpu_state[1]);
1654                         // better deal with UP
1655                 }
1656                 /* Then, the rest */
1657                 do_monitor_backside(&backside_state);
1658                 if (!rackmac)
1659                         do_monitor_drives(&drives_state);
1660                 up(&driver_lock);
1661
1662                 if (critical_state == 1) {
1663                         printk(KERN_WARNING "Temperature control detected a critical condition\n");
1664                         printk(KERN_WARNING "Attempting to shut down...\n");
1665                         if (call_critical_overtemp()) {
1666                                 printk(KERN_WARNING "Can't call %s, power off now!\n",
1667                                        critical_overtemp_path);
1668                                 machine_power_off();
1669                         }
1670                 }
1671                 if (critical_state > 0)
1672                         critical_state++;
1673                 if (critical_state > MAX_CRITICAL_STATE) {
1674                         printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1675                         machine_power_off();
1676                 }
1677
1678                 // FIXME: Deal with signals
1679                 elapsed = jiffies - start;
1680                 if (elapsed < HZ)
1681                         schedule_timeout_interruptible(HZ - elapsed);
1682         }
1683
1684  out:
1685         DBG("main_control_loop ended\n");
1686
1687         ctrl_task = 0;
1688         complete_and_exit(&ctrl_complete, 0);
1689 }
1690
1691 /*
1692  * Dispose the control loops when tearing down
1693  */
1694 static void dispose_control_loops(void)
1695 {
1696         dispose_cpu_state(&cpu_state[0]);
1697         dispose_cpu_state(&cpu_state[1]);
1698         dispose_backside_state(&backside_state);
1699         dispose_drives_state(&drives_state);
1700         dispose_dimms_state(&dimms_state);
1701 }
1702
1703 /*
1704  * Create the control loops. U3-0 i2c bus is up, so we can now
1705  * get to the various sensors
1706  */
1707 static int create_control_loops(void)
1708 {
1709         struct device_node *np;
1710
1711         /* Count CPUs from the device-tree, we don't care how many are
1712          * actually used by Linux
1713          */
1714         cpu_count = 0;
1715         for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1716                 cpu_count++;
1717
1718         DBG("counted %d CPUs in the device-tree\n", cpu_count);
1719
1720         /* Decide the type of PID algorithm to use based on the presence of
1721          * the pumps, though that may not be the best way, that is good enough
1722          * for now
1723          */
1724         if (rackmac)
1725                 cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1726         else if (machine_is_compatible("PowerMac7,3")
1727             && (cpu_count > 1)
1728             && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1729             && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1730                 printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1731                 cpu_pid_type = CPU_PID_TYPE_COMBINED;
1732         } else
1733                 cpu_pid_type = CPU_PID_TYPE_SPLIT;
1734
1735         /* Create control loops for everything. If any fail, everything
1736          * fails
1737          */
1738         if (init_cpu_state(&cpu_state[0], 0))
1739                 goto fail;
1740         if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1741                 fetch_cpu_pumps_minmax();
1742
1743         if (cpu_count > 1 && init_cpu_state(&cpu_state[1], 1))
1744                 goto fail;
1745         if (init_backside_state(&backside_state))
1746                 goto fail;
1747         if (rackmac && init_dimms_state(&dimms_state))
1748                 goto fail;
1749         if (!rackmac && init_drives_state(&drives_state))
1750                 goto fail;
1751
1752         DBG("all control loops up !\n");
1753
1754         return 0;
1755         
1756  fail:
1757         DBG("failure creating control loops, disposing\n");
1758
1759         dispose_control_loops();
1760
1761         return -ENODEV;
1762 }
1763
1764 /*
1765  * Start the control loops after everything is up, that is create
1766  * the thread that will make them run
1767  */
1768 static void start_control_loops(void)
1769 {
1770         init_completion(&ctrl_complete);
1771
1772         ctrl_task = kernel_thread(main_control_loop, NULL, SIGCHLD | CLONE_KERNEL);
1773 }
1774
1775 /*
1776  * Stop the control loops when tearing down
1777  */
1778 static void stop_control_loops(void)
1779 {
1780         if (ctrl_task != 0)
1781                 wait_for_completion(&ctrl_complete);
1782 }
1783
1784 /*
1785  * Attach to the i2c FCU after detecting U3-1 bus
1786  */
1787 static int attach_fcu(void)
1788 {
1789         fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1790         if (fcu == NULL)
1791                 return -ENODEV;
1792
1793         DBG("FCU attached\n");
1794
1795         return 0;
1796 }
1797
1798 /*
1799  * Detach from the i2c FCU when tearing down
1800  */
1801 static void detach_fcu(void)
1802 {
1803         if (fcu)
1804                 detach_i2c_chip(fcu);
1805         fcu = NULL;
1806 }
1807
1808 /*
1809  * Attach to the i2c controller. We probe the various chips based
1810  * on the device-tree nodes and build everything for the driver to
1811  * run, we then kick the driver monitoring thread
1812  */
1813 static int therm_pm72_attach(struct i2c_adapter *adapter)
1814 {
1815         down(&driver_lock);
1816
1817         /* Check state */
1818         if (state == state_detached)
1819                 state = state_attaching;
1820         if (state != state_attaching) {
1821                 up(&driver_lock);
1822                 return 0;
1823         }
1824
1825         /* Check if we are looking for one of these */
1826         if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
1827                 u3_0 = adapter;
1828                 DBG("found U3-0\n");
1829                 if (k2 || !rackmac)
1830                         if (create_control_loops())
1831                                 u3_0 = NULL;
1832         } else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
1833                 u3_1 = adapter;
1834                 DBG("found U3-1, attaching FCU\n");
1835                 if (attach_fcu())
1836                         u3_1 = NULL;
1837         } else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
1838                 k2 = adapter;
1839                 DBG("Found K2\n");
1840                 if (u3_0 && rackmac)
1841                         if (create_control_loops())
1842                                 k2 = NULL;
1843         }
1844         /* We got all we need, start control loops */
1845         if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
1846                 DBG("everything up, starting control loops\n");
1847                 state = state_attached;
1848                 start_control_loops();
1849         }
1850         up(&driver_lock);
1851
1852         return 0;
1853 }
1854
1855 /*
1856  * Called on every adapter when the driver or the i2c controller
1857  * is going away.
1858  */
1859 static int therm_pm72_detach(struct i2c_adapter *adapter)
1860 {
1861         down(&driver_lock);
1862
1863         if (state != state_detached)
1864                 state = state_detaching;
1865
1866         /* Stop control loops if any */
1867         DBG("stopping control loops\n");
1868         up(&driver_lock);
1869         stop_control_loops();
1870         down(&driver_lock);
1871
1872         if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
1873                 DBG("lost U3-0, disposing control loops\n");
1874                 dispose_control_loops();
1875                 u3_0 = NULL;
1876         }
1877         
1878         if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
1879                 DBG("lost U3-1, detaching FCU\n");
1880                 detach_fcu();
1881                 u3_1 = NULL;
1882         }
1883         if (u3_0 == NULL && u3_1 == NULL)
1884                 state = state_detached;
1885
1886         up(&driver_lock);
1887
1888         return 0;
1889 }
1890
1891 static int fan_check_loc_match(const char *loc, int fan)
1892 {
1893         char    tmp[64];
1894         char    *c, *e;
1895
1896         strlcpy(tmp, fcu_fans[fan].loc, 64);
1897
1898         c = tmp;
1899         for (;;) {
1900                 e = strchr(c, ',');
1901                 if (e)
1902                         *e = 0;
1903                 if (strcmp(loc, c) == 0)
1904                         return 1;
1905                 if (e == NULL)
1906                         break;
1907                 c = e + 1;
1908         }
1909         return 0;
1910 }
1911
1912 static void fcu_lookup_fans(struct device_node *fcu_node)
1913 {
1914         struct device_node *np = NULL;
1915         int i;
1916
1917         /* The table is filled by default with values that are suitable
1918          * for the old machines without device-tree informations. We scan
1919          * the device-tree and override those values with whatever is
1920          * there
1921          */
1922
1923         DBG("Looking up FCU controls in device-tree...\n");
1924
1925         while ((np = of_get_next_child(fcu_node, np)) != NULL) {
1926                 int type = -1;
1927                 char *loc;
1928                 u32 *reg;
1929
1930                 DBG(" control: %s, type: %s\n", np->name, np->type);
1931
1932                 /* Detect control type */
1933                 if (!strcmp(np->type, "fan-rpm-control") ||
1934                     !strcmp(np->type, "fan-rpm"))
1935                         type = FCU_FAN_RPM;
1936                 if (!strcmp(np->type, "fan-pwm-control") ||
1937                     !strcmp(np->type, "fan-pwm"))
1938                         type = FCU_FAN_PWM;
1939                 /* Only care about fans for now */
1940                 if (type == -1)
1941                         continue;
1942
1943                 /* Lookup for a matching location */
1944                 loc = (char *)get_property(np, "location", NULL);
1945                 reg = (u32 *)get_property(np, "reg", NULL);
1946                 if (loc == NULL || reg == NULL)
1947                         continue;
1948                 DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
1949
1950                 for (i = 0; i < FCU_FAN_COUNT; i++) {
1951                         int fan_id;
1952
1953                         if (!fan_check_loc_match(loc, i))
1954                                 continue;
1955                         DBG(" location match, index: %d\n", i);
1956                         fcu_fans[i].id = FCU_FAN_ABSENT_ID;
1957                         if (type != fcu_fans[i].type) {
1958                                 printk(KERN_WARNING "therm_pm72: Fan type mismatch "
1959                                        "in device-tree for %s\n", np->full_name);
1960                                 break;
1961                         }
1962                         if (type == FCU_FAN_RPM)
1963                                 fan_id = ((*reg) - 0x10) / 2;
1964                         else
1965                                 fan_id = ((*reg) - 0x30) / 2;
1966                         if (fan_id > 7) {
1967                                 printk(KERN_WARNING "therm_pm72: Can't parse "
1968                                        "fan ID in device-tree for %s\n", np->full_name);
1969                                 break;
1970                         }
1971                         DBG(" fan id -> %d, type -> %d\n", fan_id, type);
1972                         fcu_fans[i].id = fan_id;
1973                 }
1974         }
1975
1976         /* Now dump the array */
1977         printk(KERN_INFO "Detected fan controls:\n");
1978         for (i = 0; i < FCU_FAN_COUNT; i++) {
1979                 if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
1980                         continue;
1981                 printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
1982                        fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
1983                        fcu_fans[i].id, fcu_fans[i].loc);
1984         }
1985 }
1986
1987 static int fcu_of_probe(struct of_device* dev, const struct of_device_id *match)
1988 {
1989         state = state_detached;
1990
1991         /* Lookup the fans in the device tree */
1992         fcu_lookup_fans(dev->node);
1993
1994         /* Add the driver */
1995         return i2c_add_driver(&therm_pm72_driver);
1996 }
1997
1998 static int fcu_of_remove(struct of_device* dev)
1999 {
2000         i2c_del_driver(&therm_pm72_driver);
2001
2002         return 0;
2003 }
2004
2005 static struct of_device_id fcu_match[] = 
2006 {
2007         {
2008         .type           = "fcu",
2009         },
2010         {},
2011 };
2012
2013 static struct of_platform_driver fcu_of_platform_driver = 
2014 {
2015         .name           = "temperature",
2016         .match_table    = fcu_match,
2017         .probe          = fcu_of_probe,
2018         .remove         = fcu_of_remove
2019 };
2020
2021 /*
2022  * Check machine type, attach to i2c controller
2023  */
2024 static int __init therm_pm72_init(void)
2025 {
2026         struct device_node *np;
2027
2028         rackmac = machine_is_compatible("RackMac3,1");
2029
2030         if (!machine_is_compatible("PowerMac7,2") &&
2031             !machine_is_compatible("PowerMac7,3") &&
2032             !rackmac)
2033                 return -ENODEV;
2034
2035         printk(KERN_INFO "PowerMac G5 Thermal control driver %s\n", VERSION);
2036
2037         np = of_find_node_by_type(NULL, "fcu");
2038         if (np == NULL) {
2039                 /* Some machines have strangely broken device-tree */
2040                 np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
2041                 if (np == NULL) {
2042                             printk(KERN_ERR "Can't find FCU in device-tree !\n");
2043                             return -ENODEV;
2044                 }
2045         }
2046         of_dev = of_platform_device_create(np, "temperature", NULL);
2047         if (of_dev == NULL) {
2048                 printk(KERN_ERR "Can't register FCU platform device !\n");
2049                 return -ENODEV;
2050         }
2051
2052         of_register_driver(&fcu_of_platform_driver);
2053         
2054         return 0;
2055 }
2056
2057 static void __exit therm_pm72_exit(void)
2058 {
2059         of_unregister_driver(&fcu_of_platform_driver);
2060
2061         if (of_dev)
2062                 of_device_unregister(of_dev);
2063 }
2064
2065 module_init(therm_pm72_init);
2066 module_exit(therm_pm72_exit);
2067
2068 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
2069 MODULE_DESCRIPTION("Driver for Apple's PowerMac G5 thermal control");
2070 MODULE_LICENSE("GPL");
2071