/*
* Windfarm PowerMac thermal control. SMU based 1 CPU desktop control loops
*
* (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
* <benh@kernel.crashing.org>
*
* Released under the term of the GNU GPL v2.
*
* The algorithm used is the PID control algorithm, used the same
* way the published Darwin code does, using the same values that
* are present in the Darwin 8.2 snapshot property lists (note however
* that none of the code has been re-used, it's a complete re-implementation
*
* The various control loops found in Darwin config file are:
*
* PowerMac9,1
* ===========
*
* Has 3 control loops: CPU fans is similar to PowerMac8,1 (though it doesn't
* try to play with other control loops fans). Drive bay is rather basic PID
* with one sensor and one fan. Slots area is a bit different as the Darwin
* driver is supposed to be capable of working in a special "AGP" mode which
* involves the presence of an AGP sensor and an AGP fan (possibly on the
* AGP card itself). I can't deal with that special mode as I don't have
* access to those additional sensor/fans for now (though ultimately, it would
* be possible to add sensor objects for them) so I'm only implementing the
* basic PCI slot control loop
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/kmod.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/smu.h>
#include "windfarm.h"
#include "windfarm_pid.h"
#define VERSION "0.4"
#undef DEBUG
#ifdef DEBUG
#define DBG(args...) printk(args)
#else
#define DBG(args...) do { } while(0)
#endif
/* define this to force CPU overtemp to 74 degree, useful for testing
* the overtemp code
*/
#undef HACKED_OVERTEMP
/* Controls & sensors */
static struct wf_sensor *sensor_cpu_power;
static struct wf_sensor *sensor_cpu_temp;
static struct wf_sensor *sensor_hd_temp;
static struct wf_sensor *sensor_slots_power;
static struct wf_control *fan_cpu_main;
static struct wf_control *fan_cpu_second;
static struct wf_control *fan_cpu_third;
static struct wf_control *fan_hd;
static struct wf_control *fan_slots;
static struct wf_control *cpufreq_clamp;
/* Set to kick the control loop into life */
static int wf_smu_all_controls_ok, wf_smu_all_sensors_ok, wf_smu_started;
/* Failure handling.. could be nicer */
#define FAILURE_FAN 0x01
#define FAILURE_SENSOR 0x02
#define FAILURE_OVERTEMP 0x04
static unsigned int wf_smu_failure_state;
static int wf_smu_readjust, wf_smu_skipping;
/*
* ****** CPU Fans Control Loop ******
*
*/
#define WF_SMU_CPU_FANS_INTERVAL 1
#define WF_SMU_CPU_FANS_MAX_HISTORY 16
/* State data used by the cpu fans control loop
*/
struct wf_smu_cpu_fans_state {
int ticks;
s32 cpu_setpoint;
struct wf_cpu_pid_state pid;
};
static struct wf_smu_cpu_fans_state *wf_smu_cpu_fans;
/*
* ****** Drive Fan Control Loop ******
*
*/
struct wf_smu_drive_fans_state {
int ticks;
s32 setpoint;
struct wf_pid_state pid;
};
static struct wf_smu_drive_fans_state *wf_smu_drive_fans;
/*
* ****** Slots Fan Control Loop ******
*
*/
struct wf_smu_slots_fans_state {
int ticks;
s32 setpoint;
struct wf_pid_state pid;
};
static struct wf_smu_slots_fans_state *wf_smu_slots_fans;
/*
* ***** Implementation *****
*
*/
static void wf_smu_create_cpu_fans(void)
{
struct wf_cpu_pid_param pid_param;
const struct smu_sdbp_header *hdr;
struct smu_sdbp_cpupiddata *piddata;
struct smu_sdbp_fvt *fvt;
s32 tmax, tdelta, maxpow, powadj;
/* First, locate the PID params in SMU SBD */
hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
if (hdr == 0) {
printk(KERN_WARNING "windfarm: CPU PID fan config not found "
"max fan speed\n");
goto fail;
}
piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
/* Get the FVT params for operating point 0 (the only supported one
* for now) in order to get tmax
*/
hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
if (hdr) {
fvt = (struct smu_sdbp_fvt *)&hdr[1];
tmax = ((s32)fvt->maxtemp) << 16;
} else
tmax = 0x5e0000; /* 94 degree default */
/* Alloc & initialize state */
wf_smu_cpu_fans = kmalloc(sizeof(struct wf_smu_cpu_fans_state),
GFP_KERNEL);
if (wf_smu_cpu_fans == NULL)
goto fail;
wf_smu_cpu_fans->ticks = 1;
/* Fill PID params */
pid_param.interval = WF_SMU_CPU_FANS_INTERVAL;
pid_param.history_len = piddata->history_len;
if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
printk(KERN_WARNING "windfarm: History size overflow on "
"CPU control loop (%d)\n", piddata->history_len);
pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
}
pid_param.gd = piddata->gd;
pid_param.gp = piddata->gp;
pid_param.gr = piddata->gr / pid_param.history_len;
tdelta = ((s32)piddata->target_temp_delta) << 16;
maxpow = ((s32)piddata->max_power) << 16;
powadj = ((s32)piddata->power_adj) << 16;
pid_param.tmax = tmax;
pid_param.ttarget = tmax - tdelta;
pid_param.pmaxadj = maxpow - powadj;
pid_param.min = fan_cpu_main->ops->get_min(fan_cpu_main);
pid_param.max = fan_cpu_main->ops->get_max(fan_cpu_main);
wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param);
DBG("wf: CPU Fan control initialized.\n");
DBG(" ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
pid_param.min, pid_param.max);
return;
fail:
printk(KERN_WARNING "windfarm: CPU fan config not found\n"
"for this machine model, max fan speed\n");
if (cpufreq_clamp)
wf_control_set_max(cpufreq_clamp);
if (fan_cpu_main)
wf_control_set_max(fan_cpu_main);
}
static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state *st)
{
s32 new_setpoint, temp, power;
int rc;
if (--st->ticks != 0) {
if (wf_smu_readjust)
goto readjust;
return;
}
st->ticks = WF_SMU_CPU_FANS_INTERVAL;
rc = sensor_cpu_temp->ops->get_value(sensor_cpu_temp, &temp);
if (rc) {
printk(KERN_WARNING "windfarm: CPU temp sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
rc = sensor_cpu_power->ops->get_value(sensor_cpu_power, &power);
if (rc) {
printk(KERN_WARNING "windfarm: CPU power sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n",
FIX32TOPRINT(temp), FIX32TOPRINT(power));
#ifdef HACKED_OVERTEMP
if (temp > 0x4a0000)
wf_smu_failure_state |= FAILURE_OVERTEMP;
#else
if (temp > st->pid.param.tmax)
wf_smu_failure_state |= FAILURE_OVERTEMP;
#endif
new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint);
if (st->cpu_setpoint == new_setpoint)
return;
st->cpu_setpoint = new_setpoint;
readjust:
if (fan_cpu_main && wf_smu_failure_state == 0) {
rc = fan_cpu_main->ops->set_value(fan_cpu_main,
st->cpu_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: CPU main fan"
" error %d\n", rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
if (fan_cpu_second && wf_smu_failure_state == 0) {
rc = fan_cpu_second->ops->set_value(fan_cpu_second,
st->cpu_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: CPU second fan"
" error %d\n", rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
if (fan_cpu_third && wf_smu_failure_state == 0) {
rc = fan_cpu_main->ops->set_value(fan_cpu_third,
st->cpu_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: CPU third fan"
" error %d\n", rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
}
static void wf_smu_create_drive_fans(void)
{
struct wf_pid_param param = {
.interval = 5,
.history_len = 2,
.gd = 0x01e00000,
.gp = 0x00500000,
.gr = 0x00000000,
.itarget = 0x00200000,
};
/* Alloc & initialize state */
wf_smu_drive_fans = kmalloc(sizeof(struct wf_smu_drive_fans_state),
GFP_KERNEL);
if (wf_smu_drive_fans == NULL) {
printk(KERN_WARNING "windfarm: Memory allocation error"
" max fan speed\n");
goto fail;
}
wf_smu_drive_fans->ticks = 1;
/* Fill PID params */
param.additive = (fan_hd->type == WF_CONTROL_RPM_FAN);
param.min = fan_hd->ops->get_min(fan_hd);
param.max = fan_hd->ops->get_max(fan_hd);
wf_pid_init(&wf_smu_drive_fans->pid, ¶m);
DBG("wf: Drive Fan control initialized.\n");
DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
FIX32TOPRINT(param.itarget), param.min, param.max);
return;
fail:
if (fan_hd)
wf_control_set_max(fan_hd);
}
static void wf_smu_drive_fans_tick(struct wf_smu_drive_fans_state *st)
{
s32 new_setpoint, temp;
int rc;
if (--st->ticks != 0) {
if (wf_smu_readjust)
goto readjust;
return;
}
st->ticks = st->pid.param.interval;
rc = sensor_hd_temp->ops->get_value(sensor_hd_temp, &temp);
if (rc) {
printk(KERN_WARNING "windfarm: HD temp sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
DBG("wf_smu: Drive Fans tick ! HD temp: %d.%03d\n",
FIX32TOPRINT(temp));
if (temp > (st->pid.param.itarget + 0x50000))
wf_smu_failure_state |= FAILURE_OVERTEMP;
new_setpoint = wf_pid_run(&st->pid, temp);
DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint);
if (st->setpoint == new_setpoint)
return;
st->setpoint = new_setpoint;
readjust:
if (fan_hd && wf_smu_failure_state == 0) {
rc = fan_hd->ops->set_value(fan_hd, st->setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: HD fan error %d\n",
rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
}
static void wf_smu_create_slots_fans(void)
{
struct wf_pid_param param = {
.interval = 1,
.history_len = 8,
.gd = 0x00000000,
.gp = 0x00000000,
.gr = 0x00020000,
.itarget = 0x00000000
};
/* Alloc & initialize state */
wf_smu_slots_fans = kmalloc(sizeof(struct wf_smu_slots_fans_state),
GFP_KERNEL);
if (wf_smu_slots_fans == NULL) {
printk(KERN_WARNING "windfarm: Memory allocation error"
" max fan speed\n");
goto fail;
}
wf_smu_slots_fans->ticks = 1;
/* Fill PID params */
param.additive = (fan_slots->type == WF_CONTROL_RPM_FAN);
param.min = fan_slots->ops->get_min(fan_slots);
param.max = fan_slots->ops->get_max(fan_slots);
wf_pid_init(&wf_smu_slots_fans->pid, ¶m);
DBG("wf: Slots Fan control initialized.\n");
DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
FIX32TOPRINT(param.itarget), param.min, param.max);
return;
fail:
if (fan_slots)
wf_control_set_max(fan_slots);
}
static void wf_smu_slots_fans_tick(struct wf_smu_slots_fans_state *st)
{
s32 new_setpoint, power;
int rc;
if (--st->ticks != 0) {
if (wf_smu_readjust)
goto readjust;
return;
}
st->ticks = st->pid.param.interval;
rc = sensor_slots_power->ops->get_value(sensor_slots_power, &power);
if (rc) {
printk(KERN_WARNING "windfarm: Slots power sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
DBG("wf_smu: Slots Fans tick ! Slots power: %d.%03d\n",
FIX32TOPRINT(power));
#if 0 /* Check what makes a good overtemp condition */
if (power > (st->pid.param.itarget + 0x50000))
wf_smu_failure_state |= FAILURE_OVERTEMP;
#endif
new_setpoint = wf_pid_run(&st->pid, power);
DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint);
if (st->setpoint == new_setpoint)
return;
st->setpoint = new_setpoint;
readjust:
if (fan_slots && wf_smu_failure_state == 0) {
rc = fan_slots->ops->set_value(fan_slots, st->setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: Slots fan error %d\n",
rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
}
/*
* ****** Setup / Init / Misc ... ******
*
*/
static void wf_smu_tick(void)
{
unsigned int last_failure = wf_smu_failure_state;
unsigned int new_failure;
if (!wf_smu_started) {
DBG("wf: creating control loops !\n");
wf_smu_create_drive_fans();
wf_smu_create_slots_fans();
wf_smu_create_cpu_fans();
wf_smu_started = 1;
}
/* Skipping ticks */
if (wf_smu_skipping && --wf_smu_skipping)
return;
wf_smu_failure_state = 0;
if (wf_smu_drive_fans)
wf_smu_drive_fans_tick(wf_smu_drive_fans);
if (wf_smu_slots_fans)
wf_smu_slots_fans_tick(wf_smu_slots_fans);
if (wf_smu_cpu_fans)
wf_smu_cpu_fans_tick(wf_smu_cpu_fans);
wf_smu_readjust = 0;
new_failure = wf_smu_failure_state & ~last_failure;
/* If entering failure mode, clamp cpufreq and ramp all
* fans to full speed.
*/
if (wf_smu_failure_state && !last_failure) {
if (cpufreq_clamp)
wf_control_set_max(cpufreq_clamp);
if (fan_cpu_main)
wf_control_set_max(fan_cpu_main);
if (fan_cpu_second)
wf_control_set_max(fan_cpu_second);
if (fan_cpu_third)
wf_control_set_max(fan_cpu_third);
if (fan_hd)
wf_control_set_max(fan_hd);
if (fan_slots)
wf_control_set_max(fan_slots);
}
/* If leaving failure mode, unclamp cpufreq and readjust
* all fans on next iteration
*/
if (!wf_smu_failure_state && last_failure) {
if (cpufreq_clamp)
wf_control_set_min(cpufreq_clamp);
wf_smu_readjust = 1;
}
/* Overtemp condition detected, notify and start skipping a couple
* ticks to let the temperature go down
*/
if (new_failure & FAILURE_OVERTEMP) {
wf_set_overtemp();
wf_smu_skipping = 2;
}
/* We only clear the overtemp condition if overtemp is cleared
* _and_ no other failure is present. Since a sensor error will
* clear the overtemp condition (can't measure temperature) at
* the control loop levels, but we don't want to keep it clear
* here in this case
*/
if (new_failure == 0 && last_failure & FAILURE_OVERTEMP)
wf_clear_overtemp();
}
static void wf_smu_new_control(struct wf_control *ct)
{
if (wf_smu_all_controls_ok)
return;
if (fan_cpu_main == NULL && !strcmp(ct->name, "cpu-rear-fan-0")) {
if (wf_get_control(ct) == 0)
fan_cpu_main = ct;
}
if (fan_cpu_second == NULL && !strcmp(ct->name, "cpu-rear-fan-1")) {
if (wf_get_control(ct) == 0)
fan_cpu_second = ct;
}
if (fan_cpu_third == NULL && !strcmp(ct->name, "cpu-front-fan-0")) {
if (wf_get_control(ct) == 0)
fan_cpu_third = ct;
}
if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {
if (wf_get_control(ct) == 0)
cpufreq_clamp = ct;
}
if (fan_hd == NULL && !strcmp(ct->name, "drive-bay-fan")) {
if (wf_get_control(ct) == 0)
fan_hd = ct;
}
if (fan_slots == NULL && !strcmp(ct->name, "slots-fan")) {
if (wf_get_control(ct) == 0)
fan_slots = ct;
}
if (fan_cpu_main && (fan_cpu_second || fan_cpu_third) && fan_hd &&
fan_slots && cpufreq_clamp)
wf_smu_all_controls_ok = 1;
}
static void wf_smu_new_sensor(struct wf_sensor *sr)
{
if (wf_smu_all_sensors_ok)
return;
if (sensor_cpu_power == NULL && !strcmp(sr->name, "cpu-power")) {
if (wf_get_sensor(sr) == 0)
sensor_cpu_power = sr;
}
if (sensor_cpu_temp == NULL && !strcmp(sr->name, "cpu-temp")) {
if (wf_get_sensor(sr) == 0)
sensor_cpu_temp = sr;
}
if (sensor_hd_temp == NULL && !strcmp(sr->name, "hd-temp")) {
if (wf_get_sensor(sr) == 0)
sensor_hd_temp = sr;
}
if (sensor_slots_power == NULL && !strcmp(sr->name, "slots-power")) {
if (wf_get_sensor(sr) == 0)
sensor_slots_power = sr;
}
if (sensor_cpu_power && sensor_cpu_temp &&
sensor_hd_temp && sensor_slots_power)
wf_smu_all_sensors_ok = 1;
}
static int wf_smu_notify(struct notifier_block *self,
unsigned long event, void *data)
{
switch(event) {
case WF_EVENT_NEW_CONTROL:
DBG("wf: new control %s detected\n",
((struct wf_control *)data)->name);
wf_smu_new_control(data);
wf_smu_readjust = 1;
break;
case WF_EVENT_NEW_SENSOR:
DBG("wf: new sensor %s detected\n",
((struct wf_sensor *)data)->name);
wf_smu_new_sensor(data);
break;
case WF_EVENT_TICK:
if (wf_smu_all_controls_ok && wf_smu_all_sensors_ok)
wf_smu_tick();
}
return 0;
}
static struct notifier_block wf_smu_events = {
.notifier_call = wf_smu_notify,
};
static int wf_init_pm(void)
{
printk(KERN_INFO "windfarm: Initializing for Desktop G5 model\n");
return 0;
}
static int wf_smu_probe(struct platform_device *ddev)
{
wf_register_client(&wf_smu_events);
return 0;
}
static int __devexit wf_smu_remove(struct platform_device *ddev)
{
wf_unregister_client(&wf_smu_events);
/* XXX We don't have yet a guarantee that our callback isn't
* in progress when returning from wf_unregister_client, so
* we add an arbitrary delay. I'll have to fix that in the core
*/
msleep(1000);
/* Release all sensors */
/* One more crappy race: I don't think we have any guarantee here
* that the attribute callback won't race with the sensor beeing
* disposed of, and I'm not 100% certain what best way to deal
* with that except by adding locks all over... I'll do that
* eventually but heh, who ever rmmod this module anyway ?
*/
if (sensor_cpu_power)
wf_put_sensor(sensor_cpu_power);
if (sensor_cpu_temp)
wf_put_sensor(sensor_cpu_temp);
if (sensor_hd_temp)
wf_put_sensor(sensor_hd_temp);
if (sensor_slots_power)
wf_put_sensor(sensor_slots_power);
/* Release all controls */
if (fan_cpu_main)
wf_put_control(fan_cpu_main);
if (fan_cpu_second)
wf_put_control(fan_cpu_second);
if (fan_cpu_third)
wf_put_control(fan_cpu_third);
if (fan_hd)
wf_put_control(fan_hd);
if (fan_slots)
wf_put_control(fan_slots);
if (cpufreq_clamp)
wf_put_control(cpufreq_clamp);
/* Destroy control loops state structures */
if (wf_smu_slots_fans)
kfree(wf_smu_cpu_fans);
if (wf_smu_drive_fans)
kfree(wf_smu_cpu_fans);
if (wf_smu_cpu_fans)
kfree(wf_smu_cpu_fans);
return 0;
}
static struct platform_driver wf_smu_driver = {
.probe = wf_smu_probe,
.remove = __devexit_p(wf_smu_remove),
.driver = {
.name = "windfarm",
.bus = &platform_bus_type,
},
};
static int __init wf_smu_init(void)
{
int rc = -ENODEV;
if (machine_is_compatible("PowerMac9,1"))
rc = wf_init_pm();
if (rc == 0) {
#ifdef MODULE
request_module("windfarm_smu_controls");
request_module("windfarm_smu_sensors");
request_module("windfarm_lm75_sensor");
request_module("windfarm_cpufreq_clamp");
#endif /* MODULE */
platform_driver_register(&wf_smu_driver);
}
return rc;
}
static void __exit wf_smu_exit(void)
{
platform_driver_unregister(&wf_smu_driver);
}
module_init(wf_smu_init);
module_exit(wf_smu_exit);
MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
MODULE_DESCRIPTION("Thermal control logic for PowerMac9,1");
MODULE_LICENSE("GPL");
