drivers/macintosh/windfarm_pm91.c - kernel/msm-4.9 - Gitiles

 /*
  * 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/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 = wf_control_get_min(fan_cpu_main);
 	pid_param.max = wf_control_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 = wf_sensor_get(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 = wf_sensor_get(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 = wf_control_set(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 = wf_control_set(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 = wf_control_set(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 = wf_control_get_min(fan_hd);
 	param.max = wf_control_get_max(fan_hd);
 	wf_pid_init(&wf_smu_drive_fans->pid, &param);

 	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 = wf_sensor_get(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 = wf_control_set(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 = wf_control_get_min(fan_slots);
 	param.max = wf_control_get_max(fan_slots);
 	wf_pid_init(&wf_smu_slots_fans->pid, &param);

 	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 = wf_sensor_get(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 = wf_control_set(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 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 */
 	kfree(wf_smu_slots_fans);
 	kfree(wf_smu_drive_fans);
 	kfree(wf_smu_cpu_fans);

 	return 0;
 }

 static struct platform_driver wf_smu_driver = {
         .probe = wf_smu_probe,
         .remove = wf_smu_remove,
 	.driver = {
 		.name = "windfarm",
 		.owner	= THIS_MODULE,
 	},
 };


 static int __init wf_smu_init(void)
 {
 	int rc = -ENODEV;

 	if (of_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");

 MODULE_ALIAS("platform:windfarm");
	/*
	* 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/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 = wf_control_get_min(fan_cpu_main);
	pid_param.max = wf_control_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 = wf_sensor_get(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 = wf_sensor_get(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 = wf_control_set(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 = wf_control_set(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 = wf_control_set(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 = wf_control_get_min(fan_hd);
	param.max = wf_control_get_max(fan_hd);
	wf_pid_init(&wf_smu_drive_fans->pid, &param);

	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 = wf_sensor_get(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 = wf_control_set(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 = wf_control_get_min(fan_slots);
	param.max = wf_control_get_max(fan_slots);
	wf_pid_init(&wf_smu_slots_fans->pid, &param);

	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 = wf_sensor_get(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 = wf_control_set(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 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 */
	kfree(wf_smu_slots_fans);
	kfree(wf_smu_drive_fans);
	kfree(wf_smu_cpu_fans);

	return 0;
	}

	static struct platform_driver wf_smu_driver = {
	.probe = wf_smu_probe,
	.remove = wf_smu_remove,
	.driver = {
	.name = "windfarm",
	.owner = THIS_MODULE,
	},
	};


	static int __init wf_smu_init(void)
	{
	int rc = -ENODEV;

	if (of_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");

	MODULE_ALIAS("platform:windfarm");