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/system.h>
131#include <asm/sections.h>
132#include <asm/macio.h>
133
134#include "therm_pm72.h"
135
136#define VERSION "1.3"
137
138#undef DEBUG
139
140#ifdef DEBUG
141#define DBG(args...)	printk(args)
142#else
143#define DBG(args...)	do { } while(0)
144#endif
145
146
147/*
148 * Driver statics
149 */
150
151static struct platform_device *		of_dev;
152static struct i2c_adapter *		u3_0;
153static struct i2c_adapter *		u3_1;
154static struct i2c_adapter *		k2;
155static struct i2c_client *		fcu;
156static struct cpu_pid_state		processor_state[2];
157static struct basckside_pid_params	backside_params;
158static struct backside_pid_state	backside_state;
159static struct drives_pid_state		drives_state;
160static struct dimm_pid_state		dimms_state;
161static struct slots_pid_state		slots_state;
162static int				state;
163static int				cpu_count;
164static int				cpu_pid_type;
165static struct task_struct		*ctrl_task;
166static struct completion		ctrl_complete;
167static int				critical_state;
168static int				rackmac;
169static s32				dimm_output_clamp;
170static int 				fcu_rpm_shift;
171static int				fcu_tickle_ticks;
172static DEFINE_MUTEX(driver_lock);
173
174/*
175 * We have 3 types of CPU PID control. One is "split" old style control
176 * for intake & exhaust fans, the other is "combined" control for both
177 * CPUs that also deals with the pumps when present. To be "compatible"
178 * with OS X at this point, we only use "COMBINED" on the machines that
179 * are identified as having the pumps (though that identification is at
180 * least dodgy). Ultimately, we could probably switch completely to this
181 * algorithm provided we hack it to deal with the UP case
182 */
183#define CPU_PID_TYPE_SPLIT	0
184#define CPU_PID_TYPE_COMBINED	1
185#define CPU_PID_TYPE_RACKMAC	2
186
187/*
188 * This table describes all fans in the FCU. The "id" and "type" values
189 * are defaults valid for all earlier machines. Newer machines will
190 * eventually override the table content based on the device-tree
191 */
192struct fcu_fan_table
193{
194	char*	loc;	/* location code */
195	int	type;	/* 0 = rpm, 1 = pwm, 2 = pump */
196	int	id;	/* id or -1 */
197};
198
199#define FCU_FAN_RPM		0
200#define FCU_FAN_PWM		1
201
202#define FCU_FAN_ABSENT_ID	-1
203
204#define FCU_FAN_COUNT		ARRAY_SIZE(fcu_fans)
205
206struct fcu_fan_table	fcu_fans[] = {
207	[BACKSIDE_FAN_PWM_INDEX] = {
208		.loc	= "BACKSIDE,SYS CTRLR FAN",
209		.type	= FCU_FAN_PWM,
210		.id	= BACKSIDE_FAN_PWM_DEFAULT_ID,
211	},
212	[DRIVES_FAN_RPM_INDEX] = {
213		.loc	= "DRIVE BAY",
214		.type	= FCU_FAN_RPM,
215		.id	= DRIVES_FAN_RPM_DEFAULT_ID,
216	},
217	[SLOTS_FAN_PWM_INDEX] = {
218		.loc	= "SLOT,PCI FAN",
219		.type	= FCU_FAN_PWM,
220		.id	= SLOTS_FAN_PWM_DEFAULT_ID,
221	},
222	[CPUA_INTAKE_FAN_RPM_INDEX] = {
223		.loc	= "CPU A INTAKE",
224		.type	= FCU_FAN_RPM,
225		.id	= CPUA_INTAKE_FAN_RPM_DEFAULT_ID,
226	},
227	[CPUA_EXHAUST_FAN_RPM_INDEX] = {
228		.loc	= "CPU A EXHAUST",
229		.type	= FCU_FAN_RPM,
230		.id	= CPUA_EXHAUST_FAN_RPM_DEFAULT_ID,
231	},
232	[CPUB_INTAKE_FAN_RPM_INDEX] = {
233		.loc	= "CPU B INTAKE",
234		.type	= FCU_FAN_RPM,
235		.id	= CPUB_INTAKE_FAN_RPM_DEFAULT_ID,
236	},
237	[CPUB_EXHAUST_FAN_RPM_INDEX] = {
238		.loc	= "CPU B EXHAUST",
239		.type	= FCU_FAN_RPM,
240		.id	= CPUB_EXHAUST_FAN_RPM_DEFAULT_ID,
241	},
242	/* pumps aren't present by default, have to be looked up in the
243	 * device-tree
244	 */
245	[CPUA_PUMP_RPM_INDEX] = {
246		.loc	= "CPU A PUMP",
247		.type	= FCU_FAN_RPM,
248		.id	= FCU_FAN_ABSENT_ID,
249	},
250	[CPUB_PUMP_RPM_INDEX] = {
251		.loc	= "CPU B PUMP",
252		.type	= FCU_FAN_RPM,
253		.id	= FCU_FAN_ABSENT_ID,
254	},
255	/* Xserve fans */
256	[CPU_A1_FAN_RPM_INDEX] = {
257		.loc	= "CPU A 1",
258		.type	= FCU_FAN_RPM,
259		.id	= FCU_FAN_ABSENT_ID,
260	},
261	[CPU_A2_FAN_RPM_INDEX] = {
262		.loc	= "CPU A 2",
263		.type	= FCU_FAN_RPM,
264		.id	= FCU_FAN_ABSENT_ID,
265	},
266	[CPU_A3_FAN_RPM_INDEX] = {
267		.loc	= "CPU A 3",
268		.type	= FCU_FAN_RPM,
269		.id	= FCU_FAN_ABSENT_ID,
270	},
271	[CPU_B1_FAN_RPM_INDEX] = {
272		.loc	= "CPU B 1",
273		.type	= FCU_FAN_RPM,
274		.id	= FCU_FAN_ABSENT_ID,
275	},
276	[CPU_B2_FAN_RPM_INDEX] = {
277		.loc	= "CPU B 2",
278		.type	= FCU_FAN_RPM,
279		.id	= FCU_FAN_ABSENT_ID,
280	},
281	[CPU_B3_FAN_RPM_INDEX] = {
282		.loc	= "CPU B 3",
283		.type	= FCU_FAN_RPM,
284		.id	= FCU_FAN_ABSENT_ID,
285	},
286};
287
288static struct i2c_driver therm_pm72_driver;
289
290/*
291 * Utility function to create an i2c_client structure and
292 * attach it to one of u3 adapters
293 */
294static struct i2c_client *attach_i2c_chip(int id, const char *name)
295{
296	struct i2c_client *clt;
297	struct i2c_adapter *adap;
298	struct i2c_board_info info;
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	memset(&info, 0, sizeof(struct i2c_board_info));
310	info.addr = (id >> 1) & 0x7f;
311	strlcpy(info.type, "therm_pm72", I2C_NAME_SIZE);
312	clt = i2c_new_device(adap, &info);
313	if (!clt) {
314		printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
315		return NULL;
316	}
317
318	/*
319	 * Let i2c-core delete that device on driver removal.
320	 * This is safe because i2c-core holds the core_lock mutex for us.
321	 */
322	list_add_tail(&clt->detected, &therm_pm72_driver.clients);
323	return clt;
324}
325
326/*
327 * Here are the i2c chip access wrappers
328 */
329
330static void initialize_adc(struct cpu_pid_state *state)
331{
332	int rc;
333	u8 buf[2];
334
335	/* Read ADC the configuration register and cache it. We
336	 * also make sure Config2 contains proper values, I've seen
337	 * cases where we got stale grabage in there, thus preventing
338	 * proper reading of conv. values
339	 */
340
341	/* Clear Config2 */
342	buf[0] = 5;
343	buf[1] = 0;
344	i2c_master_send(state->monitor, buf, 2);
345
346	/* Read & cache Config1 */
347	buf[0] = 1;
348	rc = i2c_master_send(state->monitor, buf, 1);
349	if (rc > 0) {
350		rc = i2c_master_recv(state->monitor, buf, 1);
351		if (rc > 0) {
352			state->adc_config = buf[0];
353			DBG("ADC config reg: %02x\n", state->adc_config);
354			/* Disable shutdown mode */
355		       	state->adc_config &= 0xfe;
356			buf[0] = 1;
357			buf[1] = state->adc_config;
358			rc = i2c_master_send(state->monitor, buf, 2);
359		}
360	}
361	if (rc <= 0)
362		printk(KERN_ERR "therm_pm72: Error reading ADC config"
363		       " register !\n");
364}
365
366static int read_smon_adc(struct cpu_pid_state *state, int chan)
367{
368	int rc, data, tries = 0;
369	u8 buf[2];
370
371	for (;;) {
372		/* Set channel */
373		buf[0] = 1;
374		buf[1] = (state->adc_config & 0x1f) | (chan << 5);
375		rc = i2c_master_send(state->monitor, buf, 2);
376		if (rc <= 0)
377			goto error;
378		/* Wait for conversion */
379		msleep(1);
380		/* Switch to data register */
381		buf[0] = 4;
382		rc = i2c_master_send(state->monitor, buf, 1);
383		if (rc <= 0)
384			goto error;
385		/* Read result */
386		rc = i2c_master_recv(state->monitor, buf, 2);
387		if (rc < 0)
388			goto error;
389		data = ((u16)buf[0]) << 8 | (u16)buf[1];
390		return data >> 6;
391	error:
392		DBG("Error reading ADC, retrying...\n");
393		if (++tries > 10) {
394			printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
395			return -1;
396		}
397		msleep(10);
398	}
399}
400
401static int read_lm87_reg(struct i2c_client * chip, int reg)
402{
403	int rc, tries = 0;
404	u8 buf;
405
406	for (;;) {
407		/* Set address */
408		buf = (u8)reg;
409		rc = i2c_master_send(chip, &buf, 1);
410		if (rc <= 0)
411			goto error;
412		rc = i2c_master_recv(chip, &buf, 1);
413		if (rc <= 0)
414			goto error;
415		return (int)buf;
416	error:
417		DBG("Error reading LM87, retrying...\n");
418		if (++tries > 10) {
419			printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
420			return -1;
421		}
422		msleep(10);
423	}
424}
425
426static int fan_read_reg(int reg, unsigned char *buf, int nb)
427{
428	int tries, nr, nw;
429
430	buf[0] = reg;
431	tries = 0;
432	for (;;) {
433		nw = i2c_master_send(fcu, buf, 1);
434		if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
435			break;
436		msleep(10);
437		++tries;
438	}
439	if (nw <= 0) {
440		printk(KERN_ERR "Failure writing address to FCU: %d", nw);
441		return -EIO;
442	}
443	tries = 0;
444	for (;;) {
445		nr = i2c_master_recv(fcu, buf, nb);
446		if (nr > 0 || (nr < 0 && nr != -ENODEV) || tries >= 100)
447			break;
448		msleep(10);
449		++tries;
450	}
451	if (nr <= 0)
452		printk(KERN_ERR "Failure reading data from FCU: %d", nw);
453	return nr;
454}
455
456static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
457{
458	int tries, nw;
459	unsigned char buf[16];
460
461	buf[0] = reg;
462	memcpy(buf+1, ptr, nb);
463	++nb;
464	tries = 0;
465	for (;;) {
466		nw = i2c_master_send(fcu, buf, nb);
467		if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
468			break;
469		msleep(10);
470		++tries;
471	}
472	if (nw < 0)
473		printk(KERN_ERR "Failure writing to FCU: %d", nw);
474	return nw;
475}
476
477static int start_fcu(void)
478{
479	unsigned char buf = 0xff;
480	int rc;
481
482	rc = fan_write_reg(0xe, &buf, 1);
483	if (rc < 0)
484		return -EIO;
485	rc = fan_write_reg(0x2e, &buf, 1);
486	if (rc < 0)
487		return -EIO;
488	rc = fan_read_reg(0, &buf, 1);
489	if (rc < 0)
490		return -EIO;
491	fcu_rpm_shift = (buf == 1) ? 2 : 3;
492	printk(KERN_DEBUG "FCU Initialized, RPM fan shift is %d\n",
493	       fcu_rpm_shift);
494
495	return 0;
496}
497
498static int set_rpm_fan(int fan_index, int rpm)
499{
500	unsigned char buf[2];
501	int rc, id, min, max;
502
503	if (fcu_fans[fan_index].type != FCU_FAN_RPM)
504		return -EINVAL;
505	id = fcu_fans[fan_index].id;
506	if (id == FCU_FAN_ABSENT_ID)
507		return -EINVAL;
508
509	min = 2400 >> fcu_rpm_shift;
510	max = 56000 >> fcu_rpm_shift;
511
512	if (rpm < min)
513		rpm = min;
514	else if (rpm > max)
515		rpm = max;
516	buf[0] = rpm >> (8 - fcu_rpm_shift);
517	buf[1] = rpm << fcu_rpm_shift;
518	rc = fan_write_reg(0x10 + (id * 2), buf, 2);
519	if (rc < 0)
520		return -EIO;
521	return 0;
522}
523
524static int get_rpm_fan(int fan_index, int programmed)
525{
526	unsigned char failure;
527	unsigned char active;
528	unsigned char buf[2];
529	int rc, id, reg_base;
530
531	if (fcu_fans[fan_index].type != FCU_FAN_RPM)
532		return -EINVAL;
533	id = fcu_fans[fan_index].id;
534	if (id == FCU_FAN_ABSENT_ID)
535		return -EINVAL;
536
537	rc = fan_read_reg(0xb, &failure, 1);
538	if (rc != 1)
539		return -EIO;
540	if ((failure & (1 << id)) != 0)
541		return -EFAULT;
542	rc = fan_read_reg(0xd, &active, 1);
543	if (rc != 1)
544		return -EIO;
545	if ((active & (1 << id)) == 0)
546		return -ENXIO;
547
548	/* Programmed value or real current speed */
549	reg_base = programmed ? 0x10 : 0x11;
550	rc = fan_read_reg(reg_base + (id * 2), buf, 2);
551	if (rc != 2)
552		return -EIO;
553
554	return (buf[0] << (8 - fcu_rpm_shift)) | buf[1] >> fcu_rpm_shift;
555}
556
557static int set_pwm_fan(int fan_index, int pwm)
558{
559	unsigned char buf[2];
560	int rc, id;
561
562	if (fcu_fans[fan_index].type != FCU_FAN_PWM)
563		return -EINVAL;
564	id = fcu_fans[fan_index].id;
565	if (id == FCU_FAN_ABSENT_ID)
566		return -EINVAL;
567
568	if (pwm < 10)
569		pwm = 10;
570	else if (pwm > 100)
571		pwm = 100;
572	pwm = (pwm * 2559) / 1000;
573	buf[0] = pwm;
574	rc = fan_write_reg(0x30 + (id * 2), buf, 1);
575	if (rc < 0)
576		return rc;
577	return 0;
578}
579
580static int get_pwm_fan(int fan_index)
581{
582	unsigned char failure;
583	unsigned char active;
584	unsigned char buf[2];
585	int rc, id;
586
587	if (fcu_fans[fan_index].type != FCU_FAN_PWM)
588		return -EINVAL;
589	id = fcu_fans[fan_index].id;
590	if (id == FCU_FAN_ABSENT_ID)
591		return -EINVAL;
592
593	rc = fan_read_reg(0x2b, &failure, 1);
594	if (rc != 1)
595		return -EIO;
596	if ((failure & (1 << id)) != 0)
597		return -EFAULT;
598	rc = fan_read_reg(0x2d, &active, 1);
599	if (rc != 1)
600		return -EIO;
601	if ((active & (1 << id)) == 0)
602		return -ENXIO;
603
604	/* Programmed value or real current speed */
605	rc = fan_read_reg(0x30 + (id * 2), buf, 1);
606	if (rc != 1)
607		return -EIO;
608
609	return (buf[0] * 1000) / 2559;
610}
611
612static void tickle_fcu(void)
613{
614	int pwm;
615
616	pwm = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
617
618	DBG("FCU Tickle, slots fan is: %d\n", pwm);
619	if (pwm < 0)
620		pwm = 100;
621
622	if (!rackmac) {
623		pwm = SLOTS_FAN_DEFAULT_PWM;
624	} else if (pwm < SLOTS_PID_OUTPUT_MIN)
625		pwm = SLOTS_PID_OUTPUT_MIN;
626
627	/* That is hopefully enough to make the FCU happy */
628	set_pwm_fan(SLOTS_FAN_PWM_INDEX, pwm);
629}
630
631
632/*
633 * Utility routine to read the CPU calibration EEPROM data
634 * from the device-tree
635 */
636static int read_eeprom(int cpu, struct mpu_data *out)
637{
638	struct device_node *np;
639	char nodename[64];
640	const u8 *data;
641	int len;
642
643	/* prom.c routine for finding a node by path is a bit brain dead
644	 * and requires exact @xxx unit numbers. This is a bit ugly but
645	 * will work for these machines
646	 */
647	sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
648	np = of_find_node_by_path(nodename);
649	if (np == NULL) {
650		printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid node from device-tree\n");
651		return -ENODEV;
652	}
653	data = of_get_property(np, "cpuid", &len);
654	if (data == NULL) {
655		printk(KERN_ERR "therm_pm72: Failed to retrieve cpuid property from device-tree\n");
656		of_node_put(np);
657		return -ENODEV;
658	}
659	memcpy(out, data, sizeof(struct mpu_data));
660	of_node_put(np);
661
662	return 0;
663}
664
665static void fetch_cpu_pumps_minmax(void)
666{
667	struct cpu_pid_state *state0 = &processor_state[0];
668	struct cpu_pid_state *state1 = &processor_state[1];
669	u16 pump_min = 0, pump_max = 0xffff;
670	u16 tmp[4];
671
672	/* Try to fetch pumps min/max infos from eeprom */
673
674	memcpy(&tmp, &state0->mpu.processor_part_num, 8);
675	if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
676		pump_min = max(pump_min, tmp[0]);
677		pump_max = min(pump_max, tmp[1]);
678	}
679	if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
680		pump_min = max(pump_min, tmp[2]);
681		pump_max = min(pump_max, tmp[3]);
682	}
683
684	/* Double check the values, this _IS_ needed as the EEPROM on
685	 * some dual 2.5Ghz G5s seem, at least, to have both min & max
686	 * same to the same value ... (grrrr)
687	 */
688	if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
689		pump_min = CPU_PUMP_OUTPUT_MIN;
690		pump_max = CPU_PUMP_OUTPUT_MAX;
691	}
692
693	state0->pump_min = state1->pump_min = pump_min;
694	state0->pump_max = state1->pump_max = pump_max;
695}
696
697/*
698 * Now, unfortunately, sysfs doesn't give us a nice void * we could
699 * pass around to the attribute functions, so we don't really have
700 * choice but implement a bunch of them...
701 *
702 * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
703 * the input twice... I accept patches :)
704 */
705#define BUILD_SHOW_FUNC_FIX(name, data)				\
706static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)	\
707{								\
708	ssize_t r;						\
709	mutex_lock(&driver_lock);					\
710	r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));	\
711	mutex_unlock(&driver_lock);					\
712	return r;						\
713}
714#define BUILD_SHOW_FUNC_INT(name, data)				\
715static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)	\
716{								\
717	return sprintf(buf, "%d", data);			\
718}
719
720BUILD_SHOW_FUNC_FIX(cpu0_temperature, processor_state[0].last_temp)
721BUILD_SHOW_FUNC_FIX(cpu0_voltage, processor_state[0].voltage)
722BUILD_SHOW_FUNC_FIX(cpu0_current, processor_state[0].current_a)
723BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, processor_state[0].rpm)
724BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, processor_state[0].intake_rpm)
725
726BUILD_SHOW_FUNC_FIX(cpu1_temperature, processor_state[1].last_temp)
727BUILD_SHOW_FUNC_FIX(cpu1_voltage, processor_state[1].voltage)
728BUILD_SHOW_FUNC_FIX(cpu1_current, processor_state[1].current_a)
729BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, processor_state[1].rpm)
730BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, processor_state[1].intake_rpm)
731
732BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
733BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
734
735BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
736BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
737
738BUILD_SHOW_FUNC_FIX(slots_temperature, slots_state.last_temp)
739BUILD_SHOW_FUNC_INT(slots_fan_pwm, slots_state.pwm)
740
741BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
742
743static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
744static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
745static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
746static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
747static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
748
749static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
750static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
751static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
752static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
753static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
754
755static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
756static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
757
758static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
759static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
760
761static DEVICE_ATTR(slots_temperature,S_IRUGO,show_slots_temperature,NULL);
762static DEVICE_ATTR(slots_fan_pwm,S_IRUGO,show_slots_fan_pwm,NULL);
763
764static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
765
766/*
767 * CPUs fans control loop
768 */
769
770static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
771{
772	s32 ltemp, volts, amps;
773	int index, rc = 0;
774
775	/* Default (in case of error) */
776	*temp = state->cur_temp;
777	*power = state->cur_power;
778
779	if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
780		index = (state->index == 0) ?
781			CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
782	else
783		index = (state->index == 0) ?
784			CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
785
786	/* Read current fan status */
787	rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
788	if (rc < 0) {
789		/* XXX What do we do now ? Nothing for now, keep old value, but
790		 * return error upstream
791		 */
792		DBG("  cpu %d, fan reading error !\n", state->index);
793	} else {
794		state->rpm = rc;
795		DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
796	}
797
798	/* Get some sensor readings and scale it */
799	ltemp = read_smon_adc(state, 1);
800	if (ltemp == -1) {
801		/* XXX What do we do now ? */
802		state->overtemp++;
803		if (rc == 0)
804			rc = -EIO;
805		DBG("  cpu %d, temp reading error !\n", state->index);
806	} else {
807		/* Fixup temperature according to diode calibration
808		 */
809		DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
810		    state->index,
811		    ltemp, state->mpu.mdiode, state->mpu.bdiode);
812		*temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
813		state->last_temp = *temp;
814		DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
815	}
816
817	/*
818	 * Read voltage & current and calculate power
819	 */
820	volts = read_smon_adc(state, 3);
821	amps = read_smon_adc(state, 4);
822
823	/* Scale voltage and current raw sensor values according to fixed scales
824	 * obtained in Darwin and calculate power from I and V
825	 */
826	volts *= ADC_CPU_VOLTAGE_SCALE;
827	amps *= ADC_CPU_CURRENT_SCALE;
828	*power = (((u64)volts) * ((u64)amps)) >> 16;
829	state->voltage = volts;
830	state->current_a = amps;
831	state->last_power = *power;
832
833	DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
834	    state->index, FIX32TOPRINT(state->current_a),
835	    FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
836
837	return 0;
838}
839
840static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
841{
842	s32 power_target, integral, derivative, proportional, adj_in_target, sval;
843	s64 integ_p, deriv_p, prop_p, sum;
844	int i;
845
846	/* Calculate power target value (could be done once for all)
847	 * and convert to a 16.16 fp number
848	 */
849	power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
850	DBG("  power target: %d.%03d, error: %d.%03d\n",
851	    FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
852
853	/* Store temperature and power in history array */
854	state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
855	state->temp_history[state->cur_temp] = temp;
856	state->cur_power = (state->cur_power + 1) % state->count_power;
857	state->power_history[state->cur_power] = power;
858	state->error_history[state->cur_power] = power_target - power;
859
860	/* If first loop, fill the history table */
861	if (state->first) {
862		for (i = 0; i < (state->count_power - 1); i++) {
863			state->cur_power = (state->cur_power + 1) % state->count_power;
864			state->power_history[state->cur_power] = power;
865			state->error_history[state->cur_power] = power_target - power;
866		}
867		for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
868			state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
869			state->temp_history[state->cur_temp] = temp;
870		}
871		state->first = 0;
872	}
873
874	/* Calculate the integral term normally based on the "power" values */
875	sum = 0;
876	integral = 0;
877	for (i = 0; i < state->count_power; i++)
878		integral += state->error_history[i];
879	integral *= CPU_PID_INTERVAL;
880	DBG("  integral: %08x\n", integral);
881
882	/* Calculate the adjusted input (sense value).
883	 *   G_r is 12.20
884	 *   integ is 16.16
885	 *   so the result is 28.36
886	 *
887	 * input target is mpu.ttarget, input max is mpu.tmax
888	 */
889	integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
890	DBG("   integ_p: %d\n", (int)(integ_p >> 36));
891	sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
892	adj_in_target = (state->mpu.ttarget << 16);
893	if (adj_in_target > sval)
894		adj_in_target = sval;
895	DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
896	    state->mpu.ttarget);
897
898	/* Calculate the derivative term */
899	derivative = state->temp_history[state->cur_temp] -
900		state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
901				    % CPU_TEMP_HISTORY_SIZE];
902	derivative /= CPU_PID_INTERVAL;
903	deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
904	DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
905	sum += deriv_p;
906
907	/* Calculate the proportional term */
908	proportional = temp - adj_in_target;
909	prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
910	DBG("   prop_p: %d\n", (int)(prop_p >> 36));
911	sum += prop_p;
912
913	/* Scale sum */
914	sum >>= 36;
915
916	DBG("   sum: %d\n", (int)sum);
917	state->rpm += (s32)sum;
918}
919
920static void do_monitor_cpu_combined(void)
921{
922	struct cpu_pid_state *state0 = &processor_state[0];
923	struct cpu_pid_state *state1 = &processor_state[1];
924	s32 temp0, power0, temp1, power1;
925	s32 temp_combi, power_combi;
926	int rc, intake, pump;
927
928	rc = do_read_one_cpu_values(state0, &temp0, &power0);
929	if (rc < 0) {
930		/* XXX What do we do now ? */
931	}
932	state1->overtemp = 0;
933	rc = do_read_one_cpu_values(state1, &temp1, &power1);
934	if (rc < 0) {
935		/* XXX What do we do now ? */
936	}
937	if (state1->overtemp)
938		state0->overtemp++;
939
940	temp_combi = max(temp0, temp1);
941	power_combi = max(power0, power1);
942
943	/* Check tmax, increment overtemp if we are there. At tmax+8, we go
944	 * full blown immediately and try to trigger a shutdown
945	 */
946	if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
947		printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
948		       temp_combi >> 16);
949		state0->overtemp += CPU_MAX_OVERTEMP / 4;
950	} else if (temp_combi > (state0->mpu.tmax << 16)) {
951		state0->overtemp++;
952		printk(KERN_WARNING "Temperature %d above max %d. overtemp %d\n",
953		       temp_combi >> 16, state0->mpu.tmax, state0->overtemp);
954	} else {
955		if (state0->overtemp)
956			printk(KERN_WARNING "Temperature back down to %d\n",
957			       temp_combi >> 16);
958		state0->overtemp = 0;
959	}
960	if (state0->overtemp >= CPU_MAX_OVERTEMP)
961		critical_state = 1;
962	if (state0->overtemp > 0) {
963		state0->rpm = state0->mpu.rmaxn_exhaust_fan;
964		state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
965		pump = state0->pump_max;
966		goto do_set_fans;
967	}
968
969	/* Do the PID */
970	do_cpu_pid(state0, temp_combi, power_combi);
971
972	/* Range check */
973	state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
974	state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
975
976	/* Calculate intake fan speed */
977	intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
978	intake = max(intake, (int)state0->mpu.rminn_intake_fan);
979	intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
980	state0->intake_rpm = intake;
981
982	/* Calculate pump speed */
983	pump = (state0->rpm * state0->pump_max) /
984		state0->mpu.rmaxn_exhaust_fan;
985	pump = min(pump, state0->pump_max);
986	pump = max(pump, state0->pump_min);
987
988 do_set_fans:
989	/* We copy values from state 0 to state 1 for /sysfs */
990	state1->rpm = state0->rpm;
991	state1->intake_rpm = state0->intake_rpm;
992
993	DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
994	    state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
995
996	/* We should check for errors, shouldn't we ? But then, what
997	 * do we do once the error occurs ? For FCU notified fan
998	 * failures (-EFAULT) we probably want to notify userland
999	 * some way...
1000	 */
1001	set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1002	set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1003	set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1004	set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
1005
1006	if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1007		set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
1008	if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
1009		set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
1010}
1011
1012static void do_monitor_cpu_split(struct cpu_pid_state *state)
1013{
1014	s32 temp, power;
1015	int rc, intake;
1016
1017	/* Read current fan status */
1018	rc = do_read_one_cpu_values(state, &temp, &power);
1019	if (rc < 0) {
1020		/* XXX What do we do now ? */
1021	}
1022
1023	/* Check tmax, increment overtemp if we are there. At tmax+8, we go
1024	 * full blown immediately and try to trigger a shutdown
1025	 */
1026	if (temp >= ((state->mpu.tmax + 8) << 16)) {
1027		printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1028		       " (%d) !\n",
1029		       state->index, temp >> 16);
1030		state->overtemp += CPU_MAX_OVERTEMP / 4;
1031	} else if (temp > (state->mpu.tmax << 16)) {
1032		state->overtemp++;
1033		printk(KERN_WARNING "CPU %d temperature %d above max %d. overtemp %d\n",
1034		       state->index, temp >> 16, state->mpu.tmax, state->overtemp);
1035	} else {
1036		if (state->overtemp)
1037			printk(KERN_WARNING "CPU %d temperature back down to %d\n",
1038			       state->index, temp >> 16);
1039		state->overtemp = 0;
1040	}
1041	if (state->overtemp >= CPU_MAX_OVERTEMP)
1042		critical_state = 1;
1043	if (state->overtemp > 0) {
1044		state->rpm = state->mpu.rmaxn_exhaust_fan;
1045		state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1046		goto do_set_fans;
1047	}
1048
1049	/* Do the PID */
1050	do_cpu_pid(state, temp, power);
1051
1052	/* Range check */
1053	state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1054	state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1055
1056	/* Calculate intake fan */
1057	intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1058	intake = max(intake, (int)state->mpu.rminn_intake_fan);
1059	intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1060	state->intake_rpm = intake;
1061
1062 do_set_fans:
1063	DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1064	    state->index, (int)state->rpm, intake, state->overtemp);
1065
1066	/* We should check for errors, shouldn't we ? But then, what
1067	 * do we do once the error occurs ? For FCU notified fan
1068	 * failures (-EFAULT) we probably want to notify userland
1069	 * some way...
1070	 */
1071	if (state->index == 0) {
1072		set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1073		set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1074	} else {
1075		set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1076		set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1077	}
1078}
1079
1080static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1081{
1082	s32 temp, power, fan_min;
1083	int rc;
1084
1085	/* Read current fan status */
1086	rc = do_read_one_cpu_values(state, &temp, &power);
1087	if (rc < 0) {
1088		/* XXX What do we do now ? */
1089	}
1090
1091	/* Check tmax, increment overtemp if we are there. At tmax+8, we go
1092	 * full blown immediately and try to trigger a shutdown
1093	 */
1094	if (temp >= ((state->mpu.tmax + 8) << 16)) {
1095		printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1096		       " (%d) !\n",
1097		       state->index, temp >> 16);
1098		state->overtemp = CPU_MAX_OVERTEMP / 4;
1099	} else if (temp > (state->mpu.tmax << 16)) {
1100		state->overtemp++;
1101		printk(KERN_WARNING "CPU %d temperature %d above max %d. overtemp %d\n",
1102		       state->index, temp >> 16, state->mpu.tmax, state->overtemp);
1103	} else {
1104		if (state->overtemp)
1105			printk(KERN_WARNING "CPU %d temperature back down to %d\n",
1106			       state->index, temp >> 16);
1107		state->overtemp = 0;
1108	}
1109	if (state->overtemp >= CPU_MAX_OVERTEMP)
1110		critical_state = 1;
1111	if (state->overtemp > 0) {
1112		state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1113		goto do_set_fans;
1114	}
1115
1116	/* Do the PID */
1117	do_cpu_pid(state, temp, power);
1118
1119	/* Check clamp from dimms */
1120	fan_min = dimm_output_clamp;
1121	fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1122
1123	DBG(" CPU min mpu = %d, min dimm = %d\n",
1124	    state->mpu.rminn_intake_fan, dimm_output_clamp);
1125
1126	state->rpm = max(state->rpm, (int)fan_min);
1127	state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1128	state->intake_rpm = state->rpm;
1129
1130 do_set_fans:
1131	DBG("** CPU %d RPM: %d overtemp: %d\n",
1132	    state->index, (int)state->rpm, state->overtemp);
1133
1134	/* We should check for errors, shouldn't we ? But then, what
1135	 * do we do once the error occurs ? For FCU notified fan
1136	 * failures (-EFAULT) we probably want to notify userland
1137	 * some way...
1138	 */
1139	if (state->index == 0) {
1140		set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1141		set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1142		set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1143	} else {
1144		set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1145		set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1146		set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1147	}
1148}
1149
1150/*
1151 * Initialize the state structure for one CPU control loop
1152 */
1153static int init_processor_state(struct cpu_pid_state *state, int index)
1154{
1155	int err;
1156
1157	state->index = index;
1158	state->first = 1;
1159	state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1160	state->overtemp = 0;
1161	state->adc_config = 0x00;
1162
1163
1164	if (index == 0)
1165		state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1166	else if (index == 1)
1167		state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1168	if (state->monitor == NULL)
1169		goto fail;
1170
1171	if (read_eeprom(index, &state->mpu))
1172		goto fail;
1173
1174	state->count_power = state->mpu.tguardband;
1175	if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1176		printk(KERN_WARNING "Warning ! too many power history slots\n");
1177		state->count_power = CPU_POWER_HISTORY_SIZE;
1178	}
1179	DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1180
1181	if (index == 0) {
1182		err = device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1183		err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1184		err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1185		err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1186		err |= device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1187	} else {
1188		err = device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1189		err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1190		err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1191		err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1192		err |= device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1193	}
1194	if (err)
1195		printk(KERN_WARNING "Failed to create some of the attribute"
1196			"files for CPU %d\n", index);
1197
1198	return 0;
1199 fail:
1200	state->monitor = NULL;
1201
1202	return -ENODEV;
1203}
1204
1205/*
1206 * Dispose of the state data for one CPU control loop
1207 */
1208static void dispose_processor_state(struct cpu_pid_state *state)
1209{
1210	if (state->monitor == NULL)
1211		return;
1212
1213	if (state->index == 0) {
1214		device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1215		device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1216		device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1217		device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1218		device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1219	} else {
1220		device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1221		device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1222		device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1223		device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1224		device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1225	}
1226
1227	state->monitor = NULL;
1228}
1229
1230/*
1231 * Motherboard backside & U3 heatsink fan control loop
1232 */
1233static void do_monitor_backside(struct backside_pid_state *state)
1234{
1235	s32 temp, integral, derivative, fan_min;
1236	s64 integ_p, deriv_p, prop_p, sum;
1237	int i, rc;
1238
1239	if (--state->ticks != 0)
1240		return;
1241	state->ticks = backside_params.interval;
1242
1243	DBG("backside:\n");
1244
1245	/* Check fan status */
1246	rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1247	if (rc < 0) {
1248		printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1249		/* XXX What do we do now ? */
1250	} else
1251		state->pwm = rc;
1252	DBG("  current pwm: %d\n", state->pwm);
1253
1254	/* Get some sensor readings */
1255	temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1256	state->last_temp = temp;
1257	DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1258	    FIX32TOPRINT(backside_params.input_target));
1259
1260	/* Store temperature and error in history array */
1261	state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1262	state->sample_history[state->cur_sample] = temp;
1263	state->error_history[state->cur_sample] = temp - backside_params.input_target;
1264
1265	/* If first loop, fill the history table */
1266	if (state->first) {
1267		for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1268			state->cur_sample = (state->cur_sample + 1) %
1269				BACKSIDE_PID_HISTORY_SIZE;
1270			state->sample_history[state->cur_sample] = temp;
1271			state->error_history[state->cur_sample] =
1272				temp - backside_params.input_target;
1273		}
1274		state->first = 0;
1275	}
1276
1277	/* Calculate the integral term */
1278	sum = 0;
1279	integral = 0;
1280	for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1281		integral += state->error_history[i];
1282	integral *= backside_params.interval;
1283	DBG("  integral: %08x\n", integral);
1284	integ_p = ((s64)backside_params.G_r) * (s64)integral;
1285	DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1286	sum += integ_p;
1287
1288	/* Calculate the derivative term */
1289	derivative = state->error_history[state->cur_sample] -
1290		state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1291				    % BACKSIDE_PID_HISTORY_SIZE];
1292	derivative /= backside_params.interval;
1293	deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1294	DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1295	sum += deriv_p;
1296
1297	/* Calculate the proportional term */
1298	prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1299	DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1300	sum += prop_p;
1301
1302	/* Scale sum */
1303	sum >>= 36;
1304
1305	DBG("   sum: %d\n", (int)sum);
1306	if (backside_params.additive)
1307		state->pwm += (s32)sum;
1308	else
1309		state->pwm = sum;
1310
1311	/* Check for clamp */
1312	fan_min = (dimm_output_clamp * 100) / 14000;
1313	fan_min = max(fan_min, backside_params.output_min);
1314
1315	state->pwm = max(state->pwm, fan_min);
1316	state->pwm = min(state->pwm, backside_params.output_max);
1317
1318	DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1319	set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1320}
1321
1322/*
1323 * Initialize the state structure for the backside fan control loop
1324 */
1325static int init_backside_state(struct backside_pid_state *state)
1326{
1327	struct device_node *u3;
1328	int u3h = 1; /* conservative by default */
1329	int err;
1330
1331	/*
1332	 * There are different PID params for machines with U3 and machines
1333	 * with U3H, pick the right ones now
1334	 */
1335	u3 = of_find_node_by_path("/u3@0,f8000000");
1336	if (u3 != NULL) {
1337		const u32 *vers = of_get_property(u3, "device-rev", NULL);
1338		if (vers)
1339			if (((*vers) & 0x3f) < 0x34)
1340				u3h = 0;
1341		of_node_put(u3);
1342	}
1343
1344	if (rackmac) {
1345		backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1346		backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1347		backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1348		backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1349		backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1350		backside_params.G_r = BACKSIDE_PID_G_r;
1351		backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1352		backside_params.additive = 0;
1353	} else if (u3h) {
1354		backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1355		backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1356		backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1357		backside_params.interval = BACKSIDE_PID_INTERVAL;
1358		backside_params.G_p = BACKSIDE_PID_G_p;
1359		backside_params.G_r = BACKSIDE_PID_G_r;
1360		backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1361		backside_params.additive = 1;
1362	} else {
1363		backside_params.G_d = BACKSIDE_PID_U3_G_d;
1364		backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1365		backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1366		backside_params.interval = BACKSIDE_PID_INTERVAL;
1367		backside_params.G_p = BACKSIDE_PID_G_p;
1368		backside_params.G_r = BACKSIDE_PID_G_r;
1369		backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1370		backside_params.additive = 1;
1371	}
1372
1373	state->ticks = 1;
1374	state->first = 1;
1375	state->pwm = 50;
1376
1377	state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1378	if (state->monitor == NULL)
1379		return -ENODEV;
1380
1381	err = device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1382	err |= device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1383	if (err)
1384		printk(KERN_WARNING "Failed to create attribute file(s)"
1385			" for backside fan\n");
1386
1387	return 0;
1388}
1389
1390/*
1391 * Dispose of the state data for the backside control loop
1392 */
1393static void dispose_backside_state(struct backside_pid_state *state)
1394{
1395	if (state->monitor == NULL)
1396		return;
1397
1398	device_remove_file(&of_dev->dev, &dev_attr_backside_temperature);
1399	device_remove_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1400
1401	state->monitor = NULL;
1402}
1403
1404/*
1405 * Drives bay fan control loop
1406 */
1407static void do_monitor_drives(struct drives_pid_state *state)
1408{
1409	s32 temp, integral, derivative;
1410	s64 integ_p, deriv_p, prop_p, sum;
1411	int i, rc;
1412
1413	if (--state->ticks != 0)
1414		return;
1415	state->ticks = DRIVES_PID_INTERVAL;
1416
1417	DBG("drives:\n");
1418
1419	/* Check fan status */
1420	rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1421	if (rc < 0) {
1422		printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1423		/* XXX What do we do now ? */
1424	} else
1425		state->rpm = rc;
1426	DBG("  current rpm: %d\n", state->rpm);
1427
1428	/* Get some sensor readings */
1429	temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1430						    DS1775_TEMP)) << 8;
1431	state->last_temp = temp;
1432	DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1433	    FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1434
1435	/* Store temperature and error in history array */
1436	state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1437	state->sample_history[state->cur_sample] = temp;
1438	state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1439
1440	/* If first loop, fill the history table */
1441	if (state->first) {
1442		for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1443			state->cur_sample = (state->cur_sample + 1) %
1444				DRIVES_PID_HISTORY_SIZE;
1445			state->sample_history[state->cur_sample] = temp;
1446			state->error_history[state->cur_sample] =
1447				temp - DRIVES_PID_INPUT_TARGET;
1448		}
1449		state->first = 0;
1450	}
1451
1452	/* Calculate the integral term */
1453	sum = 0;
1454	integral = 0;
1455	for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1456		integral += state->error_history[i];
1457	integral *= DRIVES_PID_INTERVAL;
1458	DBG("  integral: %08x\n", integral);
1459	integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1460	DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1461	sum += integ_p;
1462
1463	/* Calculate the derivative term */
1464	derivative = state->error_history[state->cur_sample] -
1465		state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1466				    % DRIVES_PID_HISTORY_SIZE];
1467	derivative /= DRIVES_PID_INTERVAL;
1468	deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1469	DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1470	sum += deriv_p;
1471
1472	/* Calculate the proportional term */
1473	prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1474	DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1475	sum += prop_p;
1476
1477	/* Scale sum */
1478	sum >>= 36;
1479
1480	DBG("   sum: %d\n", (int)sum);
1481	state->rpm += (s32)sum;
1482
1483	state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1484	state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1485
1486	DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1487	set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1488}
1489
1490/*
1491 * Initialize the state structure for the drives bay fan control loop
1492 */
1493static int init_drives_state(struct drives_pid_state *state)
1494{
1495	int err;
1496
1497	state->ticks = 1;
1498	state->first = 1;
1499	state->rpm = 1000;
1500
1501	state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1502	if (state->monitor == NULL)
1503		return -ENODEV;
1504
1505	err = device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1506	err |= device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1507	if (err)
1508		printk(KERN_WARNING "Failed to create attribute file(s)"
1509			" for drives bay fan\n");
1510
1511	return 0;
1512}
1513
1514/*
1515 * Dispose of the state data for the drives control loop
1516 */
1517static void dispose_drives_state(struct drives_pid_state *state)
1518{
1519	if (state->monitor == NULL)
1520		return;
1521
1522	device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1523	device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1524
1525	state->monitor = NULL;
1526}
1527
1528/*
1529 * DIMMs temp control loop
1530 */
1531static void do_monitor_dimms(struct dimm_pid_state *state)
1532{
1533	s32 temp, integral, derivative, fan_min;
1534	s64 integ_p, deriv_p, prop_p, sum;
1535	int i;
1536
1537	if (--state->ticks != 0)
1538		return;
1539	state->ticks = DIMM_PID_INTERVAL;
1540
1541	DBG("DIMM:\n");
1542
1543	DBG("  current value: %d\n", state->output);
1544
1545	temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1546	if (temp < 0)
1547		return;
1548	temp <<= 16;
1549	state->last_temp = temp;
1550	DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1551	    FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1552
1553	/* Store temperature and error in history array */
1554	state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1555	state->sample_history[state->cur_sample] = temp;
1556	state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1557
1558	/* If first loop, fill the history table */
1559	if (state->first) {
1560		for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1561			state->cur_sample = (state->cur_sample + 1) %
1562				DIMM_PID_HISTORY_SIZE;
1563			state->sample_history[state->cur_sample] = temp;
1564			state->error_history[state->cur_sample] =
1565				temp - DIMM_PID_INPUT_TARGET;
1566		}
1567		state->first = 0;
1568	}
1569
1570	/* Calculate the integral term */
1571	sum = 0;
1572	integral = 0;
1573	for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1574		integral += state->error_history[i];
1575	integral *= DIMM_PID_INTERVAL;
1576	DBG("  integral: %08x\n", integral);
1577	integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1578	DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1579	sum += integ_p;
1580
1581	/* Calculate the derivative term */
1582	derivative = state->error_history[state->cur_sample] -
1583		state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1584				    % DIMM_PID_HISTORY_SIZE];
1585	derivative /= DIMM_PID_INTERVAL;
1586	deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1587	DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1588	sum += deriv_p;
1589
1590	/* Calculate the proportional term */
1591	prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1592	DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1593	sum += prop_p;
1594
1595	/* Scale sum */
1596	sum >>= 36;
1597
1598	DBG("   sum: %d\n", (int)sum);
1599	state->output = (s32)sum;
1600	state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1601	state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1602	dimm_output_clamp = state->output;
1603
1604	DBG("** DIMM clamp value: %d\n", (int)state->output);
1605
1606	/* Backside PID is only every 5 seconds, force backside fan clamping now */
1607	fan_min = (dimm_output_clamp * 100) / 14000;
1608	fan_min = max(fan_min, backside_params.output_min);
1609	if (backside_state.pwm < fan_min) {
1610		backside_state.pwm = fan_min;
1611		DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1612		set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1613	}
1614}
1615
1616/*
1617 * Initialize the state structure for the DIMM temp control loop
1618 */
1619static int init_dimms_state(struct dimm_pid_state *state)
1620{
1621	state->ticks = 1;
1622	state->first = 1;
1623	state->output = 4000;
1624
1625	state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1626	if (state->monitor == NULL)
1627		return -ENODEV;
1628
1629	if (device_create_file(&of_dev->dev, &dev_attr_dimms_temperature))
1630		printk(KERN_WARNING "Failed to create attribute file"
1631			" for DIMM temperature\n");
1632
1633	return 0;
1634}
1635
1636/*
1637 * Dispose of the state data for the DIMM control loop
1638 */
1639static void dispose_dimms_state(struct dimm_pid_state *state)
1640{
1641	if (state->monitor == NULL)
1642		return;
1643
1644	device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1645
1646	state->monitor = NULL;
1647}
1648
1649/*
1650 * Slots fan control loop
1651 */
1652static void do_monitor_slots(struct slots_pid_state *state)
1653{
1654	s32 temp, integral, derivative;
1655	s64 integ_p, deriv_p, prop_p, sum;
1656	int i, rc;
1657
1658	if (--state->ticks != 0)
1659		return;
1660	state->ticks = SLOTS_PID_INTERVAL;
1661
1662	DBG("slots:\n");
1663
1664	/* Check fan status */
1665	rc = get_pwm_fan(SLOTS_FAN_PWM_INDEX);
1666	if (rc < 0) {
1667		printk(KERN_WARNING "Error %d reading slots fan !\n", rc);
1668		/* XXX What do we do now ? */
1669	} else
1670		state->pwm = rc;
1671	DBG("  current pwm: %d\n", state->pwm);
1672
1673	/* Get some sensor readings */
1674	temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor,
1675						    DS1775_TEMP)) << 8;
1676	state->last_temp = temp;
1677	DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1678	    FIX32TOPRINT(SLOTS_PID_INPUT_TARGET));
1679
1680	/* Store temperature and error in history array */
1681	state->cur_sample = (state->cur_sample + 1) % SLOTS_PID_HISTORY_SIZE;
1682	state->sample_history[state->cur_sample] = temp;
1683	state->error_history[state->cur_sample] = temp - SLOTS_PID_INPUT_TARGET;
1684
1685	/* If first loop, fill the history table */
1686	if (state->first) {
1687		for (i = 0; i < (SLOTS_PID_HISTORY_SIZE - 1); i++) {
1688			state->cur_sample = (state->cur_sample + 1) %
1689				SLOTS_PID_HISTORY_SIZE;
1690			state->sample_history[state->cur_sample] = temp;
1691			state->error_history[state->cur_sample] =
1692				temp - SLOTS_PID_INPUT_TARGET;
1693		}
1694		state->first = 0;
1695	}
1696
1697	/* Calculate the integral term */
1698	sum = 0;
1699	integral = 0;
1700	for (i = 0; i < SLOTS_PID_HISTORY_SIZE; i++)
1701		integral += state->error_history[i];
1702	integral *= SLOTS_PID_INTERVAL;
1703	DBG("  integral: %08x\n", integral);
1704	integ_p = ((s64)SLOTS_PID_G_r) * (s64)integral;
1705	DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1706	sum += integ_p;
1707
1708	/* Calculate the derivative term */
1709	derivative = state->error_history[state->cur_sample] -
1710		state->error_history[(state->cur_sample + SLOTS_PID_HISTORY_SIZE - 1)
1711				    % SLOTS_PID_HISTORY_SIZE];
1712	derivative /= SLOTS_PID_INTERVAL;
1713	deriv_p = ((s64)SLOTS_PID_G_d) * (s64)derivative;
1714	DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1715	sum += deriv_p;
1716
1717	/* Calculate the proportional term */
1718	prop_p = ((s64)SLOTS_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1719	DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1720	sum += prop_p;
1721
1722	/* Scale sum */
1723	sum >>= 36;
1724
1725	DBG("   sum: %d\n", (int)sum);
1726	state->pwm = (s32)sum;
1727
1728	state->pwm = max(state->pwm, SLOTS_PID_OUTPUT_MIN);
1729	state->pwm = min(state->pwm, SLOTS_PID_OUTPUT_MAX);
1730
1731	DBG("** DRIVES PWM: %d\n", (int)state->pwm);
1732	set_pwm_fan(SLOTS_FAN_PWM_INDEX, state->pwm);
1733}
1734
1735/*
1736 * Initialize the state structure for the slots bay fan control loop
1737 */
1738static int init_slots_state(struct slots_pid_state *state)
1739{
1740	int err;
1741
1742	state->ticks = 1;
1743	state->first = 1;
1744	state->pwm = 50;
1745
1746	state->monitor = attach_i2c_chip(XSERVE_SLOTS_LM75, "slots_temp");
1747	if (state->monitor == NULL)
1748		return -ENODEV;
1749
1750	err = device_create_file(&of_dev->dev, &dev_attr_slots_temperature);
1751	err |= device_create_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1752	if (err)
1753		printk(KERN_WARNING "Failed to create attribute file(s)"
1754			" for slots bay fan\n");
1755
1756	return 0;
1757}
1758
1759/*
1760 * Dispose of the state data for the slots control loop
1761 */
1762static void dispose_slots_state(struct slots_pid_state *state)
1763{
1764	if (state->monitor == NULL)
1765		return;
1766
1767	device_remove_file(&of_dev->dev, &dev_attr_slots_temperature);
1768	device_remove_file(&of_dev->dev, &dev_attr_slots_fan_pwm);
1769
1770	state->monitor = NULL;
1771}
1772
1773
1774static int call_critical_overtemp(void)
1775{
1776	char *argv[] = { critical_overtemp_path, NULL };
1777	static char *envp[] = { "HOME=/",
1778				"TERM=linux",
1779				"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1780				NULL };
1781
1782	return call_usermodehelper(critical_overtemp_path,
1783				   argv, envp, UMH_WAIT_EXEC);
1784}
1785
1786
1787/*
1788 * Here's the kernel thread that calls the various control loops
1789 */
1790static int main_control_loop(void *x)
1791{
1792	DBG("main_control_loop started\n");
1793
1794	mutex_lock(&driver_lock);
1795
1796	if (start_fcu() < 0) {
1797		printk(KERN_ERR "kfand: failed to start FCU\n");
1798		mutex_unlock(&driver_lock);
1799		goto out;
1800	}
1801
1802	/* Set the PCI fan once for now on non-RackMac */
1803	if (!rackmac)
1804		set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1805
1806	/* Initialize ADCs */
1807	initialize_adc(&processor_state[0]);
1808	if (processor_state[1].monitor != NULL)
1809		initialize_adc(&processor_state[1]);
1810
1811	fcu_tickle_ticks = FCU_TICKLE_TICKS;
1812
1813	mutex_unlock(&driver_lock);
1814
1815	while (state == state_attached) {
1816		unsigned long elapsed, start;
1817
1818		start = jiffies;
1819
1820		mutex_lock(&driver_lock);
1821
1822		/* Tickle the FCU just in case */
1823		if (--fcu_tickle_ticks < 0) {
1824			fcu_tickle_ticks = FCU_TICKLE_TICKS;
1825			tickle_fcu();
1826		}
1827
1828		/* First, we always calculate the new DIMMs state on an Xserve */
1829		if (rackmac)
1830			do_monitor_dimms(&dimms_state);
1831
1832		/* Then, the CPUs */
1833		if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1834			do_monitor_cpu_combined();
1835		else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1836			do_monitor_cpu_rack(&processor_state[0]);
1837			if (processor_state[1].monitor != NULL)
1838				do_monitor_cpu_rack(&processor_state[1]);
1839			// better deal with UP
1840		} else {
1841			do_monitor_cpu_split(&processor_state[0]);
1842			if (processor_state[1].monitor != NULL)
1843				do_monitor_cpu_split(&processor_state[1]);
1844			// better deal with UP
1845		}
1846		/* Then, the rest */
1847		do_monitor_backside(&backside_state);
1848		if (rackmac)
1849			do_monitor_slots(&slots_state);
1850		else
1851			do_monitor_drives(&drives_state);
1852		mutex_unlock(&driver_lock);
1853
1854		if (critical_state == 1) {
1855			printk(KERN_WARNING "Temperature control detected a critical condition\n");
1856			printk(KERN_WARNING "Attempting to shut down...\n");
1857			if (call_critical_overtemp()) {
1858				printk(KERN_WARNING "Can't call %s, power off now!\n",
1859				       critical_overtemp_path);
1860				machine_power_off();
1861			}
1862		}
1863		if (critical_state > 0)
1864			critical_state++;
1865		if (critical_state > MAX_CRITICAL_STATE) {
1866			printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1867			machine_power_off();
1868		}
1869
1870		// FIXME: Deal with signals
1871		elapsed = jiffies - start;
1872		if (elapsed < HZ)
1873			schedule_timeout_interruptible(HZ - elapsed);
1874	}
1875
1876 out:
1877	DBG("main_control_loop ended\n");
1878
1879	ctrl_task = 0;
1880	complete_and_exit(&ctrl_complete, 0);
1881}
1882
1883/*
1884 * Dispose the control loops when tearing down
1885 */
1886static void dispose_control_loops(void)
1887{
1888	dispose_processor_state(&processor_state[0]);
1889	dispose_processor_state(&processor_state[1]);
1890	dispose_backside_state(&backside_state);
1891	dispose_drives_state(&drives_state);
1892	dispose_slots_state(&slots_state);
1893	dispose_dimms_state(&dimms_state);
1894}
1895
1896/*
1897 * Create the control loops. U3-0 i2c bus is up, so we can now
1898 * get to the various sensors
1899 */
1900static int create_control_loops(void)
1901{
1902	struct device_node *np;
1903
1904	/* Count CPUs from the device-tree, we don't care how many are
1905	 * actually used by Linux
1906	 */
1907	cpu_count = 0;
1908	for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1909		cpu_count++;
1910
1911	DBG("counted %d CPUs in the device-tree\n", cpu_count);
1912
1913	/* Decide the type of PID algorithm to use based on the presence of
1914	 * the pumps, though that may not be the best way, that is good enough
1915	 * for now
1916	 */
1917	if (rackmac)
1918		cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1919	else if (of_machine_is_compatible("PowerMac7,3")
1920	    && (cpu_count > 1)
1921	    && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1922	    && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1923		printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1924		cpu_pid_type = CPU_PID_TYPE_COMBINED;
1925	} else
1926		cpu_pid_type = CPU_PID_TYPE_SPLIT;
1927
1928	/* Create control loops for everything. If any fail, everything
1929	 * fails
1930	 */
1931	if (init_processor_state(&processor_state[0], 0))
1932		goto fail;
1933	if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1934		fetch_cpu_pumps_minmax();
1935
1936	if (cpu_count > 1 && init_processor_state(&processor_state[1], 1))
1937		goto fail;
1938	if (init_backside_state(&backside_state))
1939		goto fail;
1940	if (rackmac && init_dimms_state(&dimms_state))
1941		goto fail;
1942	if (rackmac && init_slots_state(&slots_state))
1943		goto fail;
1944	if (!rackmac && init_drives_state(&drives_state))
1945		goto fail;
1946
1947	DBG("all control loops up !\n");
1948
1949	return 0;
1950
1951 fail:
1952	DBG("failure creating control loops, disposing\n");
1953
1954	dispose_control_loops();
1955
1956	return -ENODEV;
1957}
1958
1959/*
1960 * Start the control loops after everything is up, that is create
1961 * the thread that will make them run
1962 */
1963static void start_control_loops(void)
1964{
1965	init_completion(&ctrl_complete);
1966
1967	ctrl_task = kthread_run(main_control_loop, NULL, "kfand");
1968}
1969
1970/*
1971 * Stop the control loops when tearing down
1972 */
1973static void stop_control_loops(void)
1974{
1975	if (ctrl_task)
1976		wait_for_completion(&ctrl_complete);
1977}
1978
1979/*
1980 * Attach to the i2c FCU after detecting U3-1 bus
1981 */
1982static int attach_fcu(void)
1983{
1984	fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1985	if (fcu == NULL)
1986		return -ENODEV;
1987
1988	DBG("FCU attached\n");
1989
1990	return 0;
1991}
1992
1993/*
1994 * Detach from the i2c FCU when tearing down
1995 */
1996static void detach_fcu(void)
1997{
1998	fcu = NULL;
1999}
2000
2001/*
2002 * Attach to the i2c controller. We probe the various chips based
2003 * on the device-tree nodes and build everything for the driver to
2004 * run, we then kick the driver monitoring thread
2005 */
2006static int therm_pm72_attach(struct i2c_adapter *adapter)
2007{
2008	mutex_lock(&driver_lock);
2009
2010	/* Check state */
2011	if (state == state_detached)
2012		state = state_attaching;
2013	if (state != state_attaching) {
2014		mutex_unlock(&driver_lock);
2015		return 0;
2016	}
2017
2018	/* Check if we are looking for one of these */
2019	if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
2020		u3_0 = adapter;
2021		DBG("found U3-0\n");
2022		if (k2 || !rackmac)
2023			if (create_control_loops())
2024				u3_0 = NULL;
2025	} else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
2026		u3_1 = adapter;
2027		DBG("found U3-1, attaching FCU\n");
2028		if (attach_fcu())
2029			u3_1 = NULL;
2030	} else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
2031		k2 = adapter;
2032		DBG("Found K2\n");
2033		if (u3_0 && rackmac)
2034			if (create_control_loops())
2035				k2 = NULL;
2036	}
2037	/* We got all we need, start control loops */
2038	if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
2039		DBG("everything up, starting control loops\n");
2040		state = state_attached;
2041		start_control_loops();
2042	}
2043	mutex_unlock(&driver_lock);
2044
2045	return 0;
2046}
2047
2048static int therm_pm72_probe(struct i2c_client *client,
2049			    const struct i2c_device_id *id)
2050{
2051	/* Always succeed, the real work was done in therm_pm72_attach() */
2052	return 0;
2053}
2054
2055/*
2056 * Called when any of the devices which participates into thermal management
2057 * is going away.
2058 */
2059static int therm_pm72_remove(struct i2c_client *client)
2060{
2061	struct i2c_adapter *adapter = client->adapter;
2062
2063	mutex_lock(&driver_lock);
2064
2065	if (state != state_detached)
2066		state = state_detaching;
2067
2068	/* Stop control loops if any */
2069	DBG("stopping control loops\n");
2070	mutex_unlock(&driver_lock);
2071	stop_control_loops();
2072	mutex_lock(&driver_lock);
2073
2074	if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
2075		DBG("lost U3-0, disposing control loops\n");
2076		dispose_control_loops();
2077		u3_0 = NULL;
2078	}
2079
2080	if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
2081		DBG("lost U3-1, detaching FCU\n");
2082		detach_fcu();
2083		u3_1 = NULL;
2084	}
2085	if (u3_0 == NULL && u3_1 == NULL)
2086		state = state_detached;
2087
2088	mutex_unlock(&driver_lock);
2089
2090	return 0;
2091}
2092
2093/*
2094 * i2c_driver structure to attach to the host i2c controller
2095 */
2096
2097static const struct i2c_device_id therm_pm72_id[] = {
2098	/*
2099	 * Fake device name, thermal management is done by several
2100	 * chips but we don't need to differentiate between them at
2101	 * this point.
2102	 */
2103	{ "therm_pm72", 0 },
2104	{ }
2105};
2106
2107static struct i2c_driver therm_pm72_driver = {
2108	.driver = {
2109		.name	= "therm_pm72",
2110	},
2111	.attach_adapter	= therm_pm72_attach,
2112	.probe		= therm_pm72_probe,
2113	.remove		= therm_pm72_remove,
2114	.id_table	= therm_pm72_id,
2115};
2116
2117static int fan_check_loc_match(const char *loc, int fan)
2118{
2119	char	tmp[64];
2120	char	*c, *e;
2121
2122	strlcpy(tmp, fcu_fans[fan].loc, 64);
2123
2124	c = tmp;
2125	for (;;) {
2126		e = strchr(c, ',');
2127		if (e)
2128			*e = 0;
2129		if (strcmp(loc, c) == 0)
2130			return 1;
2131		if (e == NULL)
2132			break;
2133		c = e + 1;
2134	}
2135	return 0;
2136}
2137
2138static void fcu_lookup_fans(struct device_node *fcu_node)
2139{
2140	struct device_node *np = NULL;
2141	int i;
2142
2143	/* The table is filled by default with values that are suitable
2144	 * for the old machines without device-tree informations. We scan
2145	 * the device-tree and override those values with whatever is
2146	 * there
2147	 */
2148
2149	DBG("Looking up FCU controls in device-tree...\n");
2150
2151	while ((np = of_get_next_child(fcu_node, np)) != NULL) {
2152		int type = -1;
2153		const char *loc;
2154		const u32 *reg;
2155
2156		DBG(" control: %s, type: %s\n", np->name, np->type);
2157
2158		/* Detect control type */
2159		if (!strcmp(np->type, "fan-rpm-control") ||
2160		    !strcmp(np->type, "fan-rpm"))
2161			type = FCU_FAN_RPM;
2162		if (!strcmp(np->type, "fan-pwm-control") ||
2163		    !strcmp(np->type, "fan-pwm"))
2164			type = FCU_FAN_PWM;
2165		/* Only care about fans for now */
2166		if (type == -1)
2167			continue;
2168
2169		/* Lookup for a matching location */
2170		loc = of_get_property(np, "location", NULL);
2171		reg = of_get_property(np, "reg", NULL);
2172		if (loc == NULL || reg == NULL)
2173			continue;
2174		DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
2175
2176		for (i = 0; i < FCU_FAN_COUNT; i++) {
2177			int fan_id;
2178
2179			if (!fan_check_loc_match(loc, i))
2180				continue;
2181			DBG(" location match, index: %d\n", i);
2182			fcu_fans[i].id = FCU_FAN_ABSENT_ID;
2183			if (type != fcu_fans[i].type) {
2184				printk(KERN_WARNING "therm_pm72: Fan type mismatch "
2185				       "in device-tree for %s\n", np->full_name);
2186				break;
2187			}
2188			if (type == FCU_FAN_RPM)
2189				fan_id = ((*reg) - 0x10) / 2;
2190			else
2191				fan_id = ((*reg) - 0x30) / 2;
2192			if (fan_id > 7) {
2193				printk(KERN_WARNING "therm_pm72: Can't parse "
2194				       "fan ID in device-tree for %s\n", np->full_name);
2195				break;
2196			}
2197			DBG(" fan id -> %d, type -> %d\n", fan_id, type);
2198			fcu_fans[i].id = fan_id;
2199		}
2200	}
2201
2202	/* Now dump the array */
2203	printk(KERN_INFO "Detected fan controls:\n");
2204	for (i = 0; i < FCU_FAN_COUNT; i++) {
2205		if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
2206			continue;
2207		printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
2208		       fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
2209		       fcu_fans[i].id, fcu_fans[i].loc);
2210	}
2211}
2212
2213static int fcu_of_probe(struct platform_device* dev)
2214{
2215	state = state_detached;
2216	of_dev = dev;
2217
2218	dev_info(&dev->dev, "PowerMac G5 Thermal control driver %s\n", VERSION);
2219
2220	/* Lookup the fans in the device tree */
2221	fcu_lookup_fans(dev->dev.of_node);
2222
2223	/* Add the driver */
2224	return i2c_add_driver(&therm_pm72_driver);
2225}
2226
2227static int fcu_of_remove(struct platform_device* dev)
2228{
2229	i2c_del_driver(&therm_pm72_driver);
2230
2231	return 0;
2232}
2233
2234static const struct of_device_id fcu_match[] =
2235{
2236	{
2237	.type		= "fcu",
2238	},
2239	{},
2240};
2241MODULE_DEVICE_TABLE(of, fcu_match);
2242
2243static struct platform_driver fcu_of_platform_driver =
2244{
2245	.driver = {
2246		.name = "temperature",
2247		.owner = THIS_MODULE,
2248		.of_match_table = fcu_match,
2249	},
2250	.probe		= fcu_of_probe,
2251	.remove		= fcu_of_remove
2252};
2253
2254/*
2255 * Check machine type, attach to i2c controller
2256 */
2257static int __init therm_pm72_init(void)
2258{
2259	rackmac = of_machine_is_compatible("RackMac3,1");
2260
2261	if (!of_machine_is_compatible("PowerMac7,2") &&
2262	    !of_machine_is_compatible("PowerMac7,3") &&
2263	    !rackmac)
2264	    	return -ENODEV;
2265
2266	return platform_driver_register(&fcu_of_platform_driver);
2267}
2268
2269static void __exit therm_pm72_exit(void)
2270{
2271	platform_driver_unregister(&fcu_of_platform_driver);
2272}
2273
2274module_init(therm_pm72_init);
2275module_exit(therm_pm72_exit);
2276
2277MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
2278MODULE_DESCRIPTION("Driver for Apple's PowerMac G5 thermal control");
2279MODULE_LICENSE("GPL");
2280
2281