2 * Windfarm PowerMac thermal control.
3 * Control loops for machines with SMU and PPC970MP processors.
5 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
6 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
8 * Use and redistribute under the terms of the GNU GPL v2.
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/kernel.h>
13 #include <linux/device.h>
14 #include <linux/platform_device.h>
15 #include <linux/reboot.h>
20 #include "windfarm_pid.h"
28 #define DBG(args...) printk(args)
30 #define DBG(args...) do { } while(0)
34 #define DBG_LOTS(args...) printk(args)
36 #define DBG_LOTS(args...) do { } while(0)
39 /* define this to force CPU overtemp to 60 degree, useful for testing
42 #undef HACKED_OVERTEMP
44 /* We currently only handle 2 chips, 4 cores... */
47 #define NR_CPU_FANS 3 * NR_CHIPS
49 /* Controls and sensors */
50 static struct wf_sensor
*sens_cpu_temp
[NR_CORES
];
51 static struct wf_sensor
*sens_cpu_power
[NR_CORES
];
52 static struct wf_sensor
*hd_temp
;
53 static struct wf_sensor
*slots_power
;
54 static struct wf_sensor
*u4_temp
;
56 static struct wf_control
*cpu_fans
[NR_CPU_FANS
];
57 static char *cpu_fan_names
[NR_CPU_FANS
] = {
65 static struct wf_control
*cpufreq_clamp
;
67 /* Second pump isn't required (and isn't actually present) */
68 #define CPU_FANS_REQD (NR_CPU_FANS - 2)
72 /* We keep a temperature history for average calculation of 180s */
73 #define CPU_TEMP_HIST_SIZE 180
75 /* Scale factor for fan speed, *100 */
76 static int cpu_fan_scale
[NR_CPU_FANS
] = {
79 97, /* inlet fans run at 97% of exhaust fan */
81 100, /* updated later */
82 100, /* updated later */
85 static struct wf_control
*backside_fan
;
86 static struct wf_control
*slots_fan
;
87 static struct wf_control
*drive_bay_fan
;
90 static struct wf_cpu_pid_state cpu_pid
[NR_CORES
];
91 static u32 cpu_thist
[CPU_TEMP_HIST_SIZE
];
92 static int cpu_thist_pt
;
93 static s64 cpu_thist_total
;
94 static s32 cpu_all_tmax
= 100 << 16;
95 static int cpu_last_target
;
96 static struct wf_pid_state backside_pid
;
97 static int backside_tick
;
98 static struct wf_pid_state slots_pid
;
99 static int slots_started
;
100 static struct wf_pid_state drive_bay_pid
;
101 static int drive_bay_tick
;
104 static int have_all_controls
;
105 static int have_all_sensors
;
108 static int failure_state
;
109 #define FAILURE_SENSOR 1
110 #define FAILURE_FAN 2
111 #define FAILURE_PERM 4
112 #define FAILURE_LOW_OVERTEMP 8
113 #define FAILURE_HIGH_OVERTEMP 16
115 /* Overtemp values */
116 #define LOW_OVER_AVERAGE 0
117 #define LOW_OVER_IMMEDIATE (10 << 16)
118 #define LOW_OVER_CLEAR ((-10) << 16)
119 #define HIGH_OVER_IMMEDIATE (14 << 16)
120 #define HIGH_OVER_AVERAGE (10 << 16)
121 #define HIGH_OVER_IMMEDIATE (14 << 16)
124 /* Implementation... */
125 static int create_cpu_loop(int cpu
)
129 struct smu_sdbp_header
*hdr
;
130 struct smu_sdbp_cpupiddata
*piddata
;
131 struct wf_cpu_pid_param pid
;
132 struct wf_control
*main_fan
= cpu_fans
[0];
136 /* Get PID params from the appropriate SAT */
137 hdr
= smu_sat_get_sdb_partition(chip
, 0xC8 + core
, NULL
);
139 printk(KERN_WARNING
"windfarm: can't get CPU PID fan config\n");
142 piddata
= (struct smu_sdbp_cpupiddata
*)&hdr
[1];
144 /* Get FVT params to get Tmax; if not found, assume default */
145 hdr
= smu_sat_get_sdb_partition(chip
, 0xC4 + core
, NULL
);
147 struct smu_sdbp_fvt
*fvt
= (struct smu_sdbp_fvt
*)&hdr
[1];
148 tmax
= fvt
->maxtemp
<< 16;
150 tmax
= 95 << 16; /* default to 95 degrees C */
152 /* We keep a global tmax for overtemp calculations */
153 if (tmax
< cpu_all_tmax
)
157 * Darwin has a minimum fan speed of 1000 rpm for the 4-way and
158 * 515 for the 2-way. That appears to be overkill, so for now,
159 * impose a minimum of 750 or 515.
161 fmin
= (nr_cores
> 2) ? 750 : 515;
163 /* Initialize PID loop */
164 pid
.interval
= 1; /* seconds */
165 pid
.history_len
= piddata
->history_len
;
166 pid
.gd
= piddata
->gd
;
167 pid
.gp
= piddata
->gp
;
168 pid
.gr
= piddata
->gr
/ piddata
->history_len
;
169 pid
.pmaxadj
= (piddata
->max_power
<< 16) - (piddata
->power_adj
<< 8);
170 pid
.ttarget
= tmax
- (piddata
->target_temp_delta
<< 16);
172 pid
.min
= main_fan
->ops
->get_min(main_fan
);
173 pid
.max
= main_fan
->ops
->get_max(main_fan
);
177 wf_cpu_pid_init(&cpu_pid
[cpu
], &pid
);
181 static void cpu_max_all_fans(void)
185 /* We max all CPU fans in case of a sensor error. We also do the
186 * cpufreq clamping now, even if it's supposedly done later by the
187 * generic code anyway, we do it earlier here to react faster
190 wf_control_set_max(cpufreq_clamp
);
191 for (i
= 0; i
< NR_CPU_FANS
; ++i
)
193 wf_control_set_max(cpu_fans
[i
]);
196 static int cpu_check_overtemp(s32 temp
)
201 /* First check for immediate overtemps */
202 if (temp
>= (cpu_all_tmax
+ LOW_OVER_IMMEDIATE
)) {
203 new_state
|= FAILURE_LOW_OVERTEMP
;
204 if ((failure_state
& FAILURE_LOW_OVERTEMP
) == 0)
205 printk(KERN_ERR
"windfarm: Overtemp due to immediate CPU"
208 if (temp
>= (cpu_all_tmax
+ HIGH_OVER_IMMEDIATE
)) {
209 new_state
|= FAILURE_HIGH_OVERTEMP
;
210 if ((failure_state
& FAILURE_HIGH_OVERTEMP
) == 0)
211 printk(KERN_ERR
"windfarm: Critical overtemp due to"
212 " immediate CPU temperature !\n");
215 /* We calculate a history of max temperatures and use that for the
216 * overtemp management
218 t_old
= cpu_thist
[cpu_thist_pt
];
219 cpu_thist
[cpu_thist_pt
] = temp
;
220 cpu_thist_pt
= (cpu_thist_pt
+ 1) % CPU_TEMP_HIST_SIZE
;
221 cpu_thist_total
-= t_old
;
222 cpu_thist_total
+= temp
;
223 t_avg
= cpu_thist_total
/ CPU_TEMP_HIST_SIZE
;
225 DBG_LOTS("t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
226 FIX32TOPRINT(t_avg
), FIX32TOPRINT(t_old
), FIX32TOPRINT(temp
));
228 /* Now check for average overtemps */
229 if (t_avg
>= (cpu_all_tmax
+ LOW_OVER_AVERAGE
)) {
230 new_state
|= FAILURE_LOW_OVERTEMP
;
231 if ((failure_state
& FAILURE_LOW_OVERTEMP
) == 0)
232 printk(KERN_ERR
"windfarm: Overtemp due to average CPU"
235 if (t_avg
>= (cpu_all_tmax
+ HIGH_OVER_AVERAGE
)) {
236 new_state
|= FAILURE_HIGH_OVERTEMP
;
237 if ((failure_state
& FAILURE_HIGH_OVERTEMP
) == 0)
238 printk(KERN_ERR
"windfarm: Critical overtemp due to"
239 " average CPU temperature !\n");
242 /* Now handle overtemp conditions. We don't currently use the windfarm
243 * overtemp handling core as it's not fully suited to the needs of those
244 * new machine. This will be fixed later.
247 /* High overtemp -> immediate shutdown */
248 if (new_state
& FAILURE_HIGH_OVERTEMP
)
250 if ((failure_state
& new_state
) != new_state
)
252 failure_state
|= new_state
;
253 } else if ((failure_state
& FAILURE_LOW_OVERTEMP
) &&
254 (temp
< (cpu_all_tmax
+ LOW_OVER_CLEAR
))) {
255 printk(KERN_ERR
"windfarm: Overtemp condition cleared !\n");
256 failure_state
&= ~FAILURE_LOW_OVERTEMP
;
259 return failure_state
& (FAILURE_LOW_OVERTEMP
| FAILURE_HIGH_OVERTEMP
);
262 static void cpu_fans_tick(void)
265 s32 greatest_delta
= 0;
266 s32 temp
, power
, t_max
= 0;
267 int i
, t
, target
= 0;
268 struct wf_sensor
*sr
;
269 struct wf_control
*ct
;
270 struct wf_cpu_pid_state
*sp
;
272 DBG_LOTS(KERN_DEBUG
);
273 for (cpu
= 0; cpu
< nr_cores
; ++cpu
) {
274 /* Get CPU core temperature */
275 sr
= sens_cpu_temp
[cpu
];
276 err
= sr
->ops
->get_value(sr
, &temp
);
279 printk(KERN_WARNING
"windfarm: CPU %d temperature "
280 "sensor error %d\n", cpu
, err
);
281 failure_state
|= FAILURE_SENSOR
;
286 /* Keep track of highest temp */
287 t_max
= max(t_max
, temp
);
290 sr
= sens_cpu_power
[cpu
];
291 err
= sr
->ops
->get_value(sr
, &power
);
294 printk(KERN_WARNING
"windfarm: CPU %d power "
295 "sensor error %d\n", cpu
, err
);
296 failure_state
|= FAILURE_SENSOR
;
303 t
= wf_cpu_pid_run(sp
, power
, temp
);
305 if (cpu
== 0 || sp
->last_delta
> greatest_delta
) {
306 greatest_delta
= sp
->last_delta
;
309 DBG_LOTS("[%d] P=%d.%.3d T=%d.%.3d ",
310 cpu
, FIX32TOPRINT(power
), FIX32TOPRINT(temp
));
312 DBG_LOTS("fans = %d, t_max = %d.%03d\n", target
, FIX32TOPRINT(t_max
));
314 /* Darwin limits decrease to 20 per iteration */
315 if (target
< (cpu_last_target
- 20))
316 target
= cpu_last_target
- 20;
317 cpu_last_target
= target
;
318 for (cpu
= 0; cpu
< nr_cores
; ++cpu
)
319 cpu_pid
[cpu
].target
= target
;
321 /* Handle possible overtemps */
322 if (cpu_check_overtemp(t_max
))
326 for (i
= 0; i
< NR_CPU_FANS
; ++i
) {
330 err
= ct
->ops
->set_value(ct
, target
* cpu_fan_scale
[i
] / 100);
332 printk(KERN_WARNING
"windfarm: fan %s reports "
333 "error %d\n", ct
->name
, err
);
334 failure_state
|= FAILURE_FAN
;
340 /* Backside/U4 fan */
341 static struct wf_pid_param backside_param
= {
351 static void backside_fan_tick(void)
357 if (!backside_fan
|| !u4_temp
)
359 if (!backside_tick
) {
360 /* first time; initialize things */
361 backside_param
.min
= backside_fan
->ops
->get_min(backside_fan
);
362 backside_param
.max
= backside_fan
->ops
->get_max(backside_fan
);
363 wf_pid_init(&backside_pid
, &backside_param
);
366 if (--backside_tick
> 0)
368 backside_tick
= backside_pid
.param
.interval
;
370 err
= u4_temp
->ops
->get_value(u4_temp
, &temp
);
372 printk(KERN_WARNING
"windfarm: U4 temp sensor error %d\n",
374 failure_state
|= FAILURE_SENSOR
;
375 wf_control_set_max(backside_fan
);
378 speed
= wf_pid_run(&backside_pid
, temp
);
379 DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
380 FIX32TOPRINT(temp
), speed
);
382 err
= backside_fan
->ops
->set_value(backside_fan
, speed
);
384 printk(KERN_WARNING
"windfarm: backside fan error %d\n", err
);
385 failure_state
|= FAILURE_FAN
;
390 static struct wf_pid_param drive_bay_prm
= {
400 static void drive_bay_fan_tick(void)
406 if (!drive_bay_fan
|| !hd_temp
)
408 if (!drive_bay_tick
) {
409 /* first time; initialize things */
410 drive_bay_prm
.min
= drive_bay_fan
->ops
->get_min(drive_bay_fan
);
411 drive_bay_prm
.max
= drive_bay_fan
->ops
->get_max(drive_bay_fan
);
412 wf_pid_init(&drive_bay_pid
, &drive_bay_prm
);
415 if (--drive_bay_tick
> 0)
417 drive_bay_tick
= drive_bay_pid
.param
.interval
;
419 err
= hd_temp
->ops
->get_value(hd_temp
, &temp
);
421 printk(KERN_WARNING
"windfarm: drive bay temp sensor "
423 failure_state
|= FAILURE_SENSOR
;
424 wf_control_set_max(drive_bay_fan
);
427 speed
= wf_pid_run(&drive_bay_pid
, temp
);
428 DBG_LOTS("drive_bay PID temp=%d.%.3d speed=%d\n",
429 FIX32TOPRINT(temp
), speed
);
431 err
= drive_bay_fan
->ops
->set_value(drive_bay_fan
, speed
);
433 printk(KERN_WARNING
"windfarm: drive bay fan error %d\n", err
);
434 failure_state
|= FAILURE_FAN
;
438 /* PCI slots area fan */
439 /* This makes the fan speed proportional to the power consumed */
440 static struct wf_pid_param slots_param
= {
451 static void slots_fan_tick(void)
457 if (!slots_fan
|| !slots_power
)
459 if (!slots_started
) {
460 /* first time; initialize things */
461 wf_pid_init(&slots_pid
, &slots_param
);
465 err
= slots_power
->ops
->get_value(slots_power
, &power
);
467 printk(KERN_WARNING
"windfarm: slots power sensor error %d\n",
469 failure_state
|= FAILURE_SENSOR
;
470 wf_control_set_max(slots_fan
);
473 speed
= wf_pid_run(&slots_pid
, power
);
474 DBG_LOTS("slots PID power=%d.%.3d speed=%d\n",
475 FIX32TOPRINT(power
), speed
);
477 err
= slots_fan
->ops
->set_value(slots_fan
, speed
);
479 printk(KERN_WARNING
"windfarm: slots fan error %d\n", err
);
480 failure_state
|= FAILURE_FAN
;
484 static void set_fail_state(void)
489 wf_control_set_max(cpufreq_clamp
);
490 for (i
= 0; i
< NR_CPU_FANS
; ++i
)
492 wf_control_set_max(cpu_fans
[i
]);
494 wf_control_set_max(backside_fan
);
496 wf_control_set_max(slots_fan
);
498 wf_control_set_max(drive_bay_fan
);
501 static void pm112_tick(void)
507 for (i
= 0; i
< nr_cores
; ++i
) {
508 if (create_cpu_loop(i
) < 0) {
509 failure_state
= FAILURE_PERM
;
514 DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax
));
516 #ifdef HACKED_OVERTEMP
517 cpu_all_tmax
= 60 << 16;
521 /* Permanent failure, bail out */
522 if (failure_state
& FAILURE_PERM
)
524 /* Clear all failure bits except low overtemp which will be eventually
525 * cleared by the control loop itself
527 last_failure
= failure_state
;
528 failure_state
&= FAILURE_LOW_OVERTEMP
;
532 drive_bay_fan_tick();
534 DBG_LOTS("last_failure: 0x%x, failure_state: %x\n",
535 last_failure
, failure_state
);
537 /* Check for failures. Any failure causes cpufreq clamping */
538 if (failure_state
&& last_failure
== 0 && cpufreq_clamp
)
539 wf_control_set_max(cpufreq_clamp
);
540 if (failure_state
== 0 && last_failure
&& cpufreq_clamp
)
541 wf_control_set_min(cpufreq_clamp
);
543 /* That's it for now, we might want to deal with other failures
544 * differently in the future though
548 static void pm112_new_control(struct wf_control
*ct
)
552 if (cpufreq_clamp
== NULL
&& !strcmp(ct
->name
, "cpufreq-clamp")) {
553 if (wf_get_control(ct
) == 0)
557 for (i
= 0; i
< NR_CPU_FANS
; ++i
) {
558 if (!strcmp(ct
->name
, cpu_fan_names
[i
])) {
559 if (cpu_fans
[i
] == NULL
&& wf_get_control(ct
) == 0)
564 if (i
>= NR_CPU_FANS
) {
565 /* not a CPU fan, try the others */
566 if (!strcmp(ct
->name
, "backside-fan")) {
567 if (backside_fan
== NULL
&& wf_get_control(ct
) == 0)
569 } else if (!strcmp(ct
->name
, "slots-fan")) {
570 if (slots_fan
== NULL
&& wf_get_control(ct
) == 0)
572 } else if (!strcmp(ct
->name
, "drive-bay-fan")) {
573 if (drive_bay_fan
== NULL
&& wf_get_control(ct
) == 0)
579 for (i
= 0; i
< CPU_FANS_REQD
; ++i
)
580 if (cpu_fans
[i
] == NULL
)
583 /* work out pump scaling factors */
584 max_exhaust
= cpu_fans
[0]->ops
->get_max(cpu_fans
[0]);
585 for (i
= FIRST_PUMP
; i
<= LAST_PUMP
; ++i
)
586 if ((ct
= cpu_fans
[i
]) != NULL
)
588 ct
->ops
->get_max(ct
) * 100 / max_exhaust
;
590 have_all_controls
= 1;
593 static void pm112_new_sensor(struct wf_sensor
*sr
)
597 if (have_all_sensors
)
599 if (!strncmp(sr
->name
, "cpu-temp-", 9)) {
600 i
= sr
->name
[9] - '0';
601 if (sr
->name
[10] == 0 && i
< NR_CORES
&&
602 sens_cpu_temp
[i
] == NULL
&& wf_get_sensor(sr
) == 0)
603 sens_cpu_temp
[i
] = sr
;
605 } else if (!strncmp(sr
->name
, "cpu-power-", 10)) {
606 i
= sr
->name
[10] - '0';
607 if (sr
->name
[11] == 0 && i
< NR_CORES
&&
608 sens_cpu_power
[i
] == NULL
&& wf_get_sensor(sr
) == 0)
609 sens_cpu_power
[i
] = sr
;
610 } else if (!strcmp(sr
->name
, "hd-temp")) {
611 if (hd_temp
== NULL
&& wf_get_sensor(sr
) == 0)
613 } else if (!strcmp(sr
->name
, "slots-power")) {
614 if (slots_power
== NULL
&& wf_get_sensor(sr
) == 0)
616 } else if (!strcmp(sr
->name
, "u4-temp")) {
617 if (u4_temp
== NULL
&& wf_get_sensor(sr
) == 0)
622 /* check if we have all the sensors we need */
623 for (i
= 0; i
< nr_cores
; ++i
)
624 if (sens_cpu_temp
[i
] == NULL
|| sens_cpu_power
[i
] == NULL
)
627 have_all_sensors
= 1;
630 static int pm112_wf_notify(struct notifier_block
*self
,
631 unsigned long event
, void *data
)
634 case WF_EVENT_NEW_SENSOR
:
635 pm112_new_sensor(data
);
637 case WF_EVENT_NEW_CONTROL
:
638 pm112_new_control(data
);
641 if (have_all_controls
&& have_all_sensors
)
647 static struct notifier_block pm112_events
= {
648 .notifier_call
= pm112_wf_notify
,
651 static int wf_pm112_probe(struct device
*dev
)
653 wf_register_client(&pm112_events
);
657 static int wf_pm112_remove(struct device
*dev
)
659 wf_unregister_client(&pm112_events
);
660 /* should release all sensors and controls */
664 static struct device_driver wf_pm112_driver
= {
666 .bus
= &platform_bus_type
,
667 .probe
= wf_pm112_probe
,
668 .remove
= wf_pm112_remove
,
671 static int __init
wf_pm112_init(void)
673 struct device_node
*cpu
;
675 if (!machine_is_compatible("PowerMac11,2"))
678 /* Count the number of CPU cores */
680 for (cpu
= NULL
; (cpu
= of_find_node_by_type(cpu
, "cpu")) != NULL
; )
683 printk(KERN_INFO
"windfarm: initializing for dual-core desktop G5\n");
684 driver_register(&wf_pm112_driver
);
688 static void __exit
wf_pm112_exit(void)
690 driver_unregister(&wf_pm112_driver
);
693 module_init(wf_pm112_init
);
694 module_exit(wf_pm112_exit
);
696 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
697 MODULE_DESCRIPTION("Thermal control for PowerMac11,2");
698 MODULE_LICENSE("GPL");