Initial file dump from open source releaseHEADmaster

1 files changed, 350 insertions, 0 deletions

diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
new file mode 100644
index 00000000..9f012873
--- /dev/null
+++ b/drivers/thermal/step_wise.c
@@ -0,0 +1,350 @@
+/*
+ *  step_wise.c - A step-by-step Thermal throttling governor
+ *
+ *  Copyright (C) 2012 Intel Corp
+ *  Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+/*
+ * If the temperature is higher than a trip point,
+ *    a. if the trend is THERMAL_TREND_RAISING, use higher cooling
+ *       state for this trip point
+ *    b. if the trend is THERMAL_TREND_DROPPING, use lower cooling
+ *       state for this trip point
+ *    c. if the trend is THERMAL_TREND_RAISE_FULL, use upper limit
+ *       for this trip point
+ *    d. if the trend is THERMAL_TREND_DROP_FULL, use lower limit
+ *       for this trip point
+ * If the temperature is lower than a trip point,
+ *    a. if the trend is THERMAL_TREND_RAISING, do nothing
+ *    b. if the trend is THERMAL_TREND_DROPPING, use lower cooling
+ *       state for this trip point, if the cooling state already
+ *       equals lower limit, deactivate the thermal instance
+ *    c. if the trend is THERMAL_TREND_RAISE_FULL, do nothing
+ *    d. if the trend is THERMAL_TREND_DROP_FULL, use lower limit,
+ *       if the cooling state already equals lower limit,
+ *       deactive the thermal instance
+ */
+#if 0
+static unsigned long get_target_state(struct thermal_instance *instance,
+				enum thermal_trend trend, bool throttle)
+{
+	struct thermal_cooling_device *cdev = instance->cdev;
+	unsigned long cur_state;
+
+	cdev->ops->get_cur_state(cdev, &cur_state);
+	dev_dbg(&cdev->device, "cur_state=%ld\n", cur_state);
+
+	switch (trend) {
+	case THERMAL_TREND_RAISING:
+		if (throttle) {
+			cur_state = cur_state < instance->upper ?
+				    (cur_state + 1) : instance->upper;
+			if (cur_state < instance->lower)
+				cur_state = instance->lower;
+		}
+		break;
+	case THERMAL_TREND_RAISE_FULL:
+		if (throttle)
+			cur_state = instance->upper;
+		break;
+	case THERMAL_TREND_DROPPING:
+		if (cur_state == instance->lower) {
+			if (!throttle)
+				cur_state = -1;
+		} else {
+			cur_state -= 1;
+			if (cur_state > instance->upper)
+				cur_state = instance->upper;
+		}
+		break;
+	case THERMAL_TREND_DROP_FULL:
+		if (cur_state == instance->lower) {
+			if (!throttle)
+				cur_state = -1;
+		} else
+			cur_state = instance->lower;
+		break;
+	default:
+		break;
+	}
+
+	return cur_state;
+}
+
+static void update_passive_instance(struct thermal_zone_device *tz,
+				enum thermal_trip_type type, int value)
+{
+	/*
+	 * If value is +1, activate a passive instance.
+	 * If value is -1, deactivate a passive instance.
+	 */
+	if (type == THERMAL_TRIP_PASSIVE || type == THERMAL_TRIPS_NONE)
+		tz->passive += value;
+}
+
+static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
+{
+	long trip_temp;
+	enum thermal_trip_type trip_type;
+	enum thermal_trend trend;
+	struct thermal_instance *instance;
+	bool throttle = false;
+	int old_target;
+
+	if (trip == THERMAL_TRIPS_NONE) {
+		trip_temp = tz->forced_passive;
+		trip_type = THERMAL_TRIPS_NONE;
+	} else {
+		tz->ops->get_trip_temp(tz, trip, &trip_temp);
+		tz->ops->get_trip_type(tz, trip, &trip_type);
+	}
+
+	trend = get_tz_trend(tz, trip);
+
+	if (tz->temperature >= trip_temp)
+		throttle = true;
+
+	dev_dbg(&tz->device, "Trip%d[type=%d,temp=%ld]:trend=%d,throttle=%d\n",
+				trip, trip_type, trip_temp, trend, throttle);
+
+	mutex_lock(&tz->lock);
+
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+		if (instance->trip != trip)
+			continue;
+
+		old_target = instance->target;
+		instance->target = get_target_state(instance, trend, throttle);
+		dev_dbg(&instance->cdev->device, "old_target=%d, target=%d\n",
+					old_target, (int)instance->target);
+
+		/* Activate a passive thermal instance */
+		if (old_target == THERMAL_NO_TARGET &&
+			instance->target != THERMAL_NO_TARGET)
+			update_passive_instance(tz, trip_type, 1);
+		/* Deactivate a passive thermal instance */
+		else if (old_target != THERMAL_NO_TARGET &&
+			instance->target == THERMAL_NO_TARGET)
+			update_passive_instance(tz, trip_type, -1);
+
+
+		instance->cdev->updated = false; /* cdev needs update */
+	}
+
+	mutex_unlock(&tz->lock);
+}
+#else
+
+static unsigned long get_hyst_target(struct thermal_zone_device *tz, int trip)
+{
+	int count;
+	unsigned long trip_temp, trip_hyst, hyst_temp;
+
+	if (tz->trips == 0 || !tz->ops->get_trip_hyst){
+		return 0;
+	}
+	for (count = 0; count < tz->trips; count++) {
+		tz->ops->get_trip_temp(tz, count, &trip_temp);
+		tz->ops->get_trip_hyst(tz, count, &trip_hyst);
+		hyst_temp = trip_temp - trip_hyst;
+		printk("trip:%d, temp:%d, hyst_temp:%d\n", count, tz->temperature, hyst_temp);
+		if (tz->temperature < (long)hyst_temp  + TRIP_TEMP_OFFSET)
+			break;
+	}
+	if (trip == count) {
+		return count;
+	} else {
+		return THERMAL_NO_TARGET;
+	}
+}
+
+static unsigned long get_trip_target(struct thermal_zone_device *tz, int trip)
+{
+	int count = 0;
+	unsigned long trip_temp;
+
+	if (tz->trips == 0 || !tz->ops->get_trip_temp)
+		return 0;
+
+	for (count = tz->trips - 1; count >= 0; count--) {
+		tz->ops->get_trip_temp(tz, count, &trip_temp);
+		printk("trip:%d, temp:%d, trip_temp:%d\n", count, tz->temperature, trip_temp);
+		if (tz->temperature > (long)trip_temp  - TRIP_TEMP_OFFSET)
+			break;
+	}
+	if (trip == count) {
+		return count + 1;
+	} else {
+		return THERMAL_NO_TARGET;
+	}
+
+}
+
+static unsigned long get_step_wise_target(struct thermal_instance *instance,
+		struct thermal_zone_device *tz, int trip)
+{
+	struct thermal_cooling_device *cdev = instance->cdev;
+	enum thermal_trend trend;
+	unsigned long cur_target;
+	unsigned long cdev_state;
+	unsigned long new_target;
+
+	cur_target = instance->target;
+	printk("%s:%s trip:%d cur_target:%d\n", __func__, cdev->type, trip, cur_target);
+	cdev->ops->get_cur_state(cdev, &cdev_state);
+	printk("%s:%s trip:%d cdev_state:%d\n", __func__, cdev->type, trip, cdev_state);
+	if (cdev_state == THERMAL_NO_TARGET){
+		cdev_state = instance->lower;
+	}
+	if (tz->ops->get_trend){
+		tz->ops->get_trend(tz, trip, &trend);
+	}else{
+		new_target = get_trip_target(tz, trip);
+		printk("%s: %s trip:%d new_target:%d\n", __func__, cdev->type, trip, new_target);
+		if (new_target == THERMAL_NO_TARGET) {
+			return THERMAL_NO_TARGET;
+		}
+		if (new_target < cdev_state){
+			trend = THERMAL_TREND_DROPPING;
+			if (!tz->ops->get_trip_hyst){
+				goto dropping;
+			}
+		}else if(new_target >= cdev_state){
+			goto raising;
+		}
+	}
+	switch (trend){
+		case THERMAL_TREND_RAISING:
+			new_target = get_trip_target(tz, trip);
+			printk("%s: %s trend raising, target:%d\n", __func__, cdev->type,  new_target);
+			if (new_target == THERMAL_NO_TARGET) {
+				return THERMAL_NO_TARGET;
+			}
+			goto raising;
+		case THERMAL_TREND_DROPPING:
+#if 0
+			if (tz->ops->get_trip_hyst){
+				new_target = get_hyst_target(tz, trip);
+			}else{
+				new_target = get_trip_target(tz, trip);
+			}
+			printk("%s: %s trend dropping, target:%d\n", cdev->type, __func__, new_target);
+			if (new_target == THERMAL_NO_TARGET) {
+				return THERMAL_NO_TARGET;
+			}
+#endif
+			goto dropping;
+		case THERMAL_TREND_STABLE:
+		default:
+			printk("%s: %s trend stable\n", cdev->type, __func__);
+			return THERMAL_NO_TARGET;
+	}
+raising:
+	if (cdev_state > trip){
+		cdev_state = trip;
+	}
+	return cdev_state + 1;
+dropping:
+	if (cur_target != THERMAL_NO_TARGET && cur_target > 0){
+		return cur_target - 1;
+	}
+	return cur_target;
+
+}
+
+static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
+{
+	struct thermal_instance *instance;
+	unsigned long target;
+
+	mutex_lock(&tz->lock);
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+		if (instance->trip != trip)
+			continue;
+		target = get_step_wise_target(instance, tz, trip);
+		printk("%s: get target_state: %d\n", instance->cdev->type, target);
+		if (target == THERMAL_NO_TARGET){
+			continue;
+		}
+		if (target < instance->lower){
+			target = instance->lower;
+		}
+		if (target > instance->upper){
+			target = instance->upper;
+		}
+		instance->target  = target;
+		instance->cdev->updated = false; /* cdev needs update */
+	}
+	mutex_unlock(&tz->lock);
+
+	return;
+}
+#endif
+
+/**
+ * step_wise_throttle - throttles devices asscciated with the given zone
+ * @tz - thermal_zone_device
+ * @trip - the trip point
+ * @trip_type - type of the trip point
+ *
+ * Throttling Logic: This uses the trend of the thermal zone to throttle.
+ * If the thermal zone is 'heating up' this throttles all the cooling
+ * devices associated with the zone and its particular trip point, by one
+ * step. If the zone is 'cooling down' it brings back the performance of
+ * the devices by one step.
+ */
+static int step_wise_throttle(struct thermal_zone_device *tz, int trip)
+{
+	struct thermal_instance *instance;
+
+	thermal_zone_trip_update(tz, trip);
+
+	if (tz->forced_passive)
+		thermal_zone_trip_update(tz, THERMAL_TRIPS_NONE);
+
+	mutex_lock(&tz->lock);
+
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node)
+		thermal_cdev_update(instance->cdev);
+
+	mutex_unlock(&tz->lock);
+
+	return 0;
+}
+
+static struct thermal_governor thermal_gov_step_wise = {
+	.name		= "step_wise",
+	.throttle	= step_wise_throttle,
+};
+
+int thermal_gov_step_wise_register(void)
+{
+	return thermal_register_governor(&thermal_gov_step_wise);
+}
+
+void thermal_gov_step_wise_unregister(void)
+{
+	thermal_unregister_governor(&thermal_gov_step_wise);
+}