thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
# governors
-thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
+thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += gov_fair_share.o
thermal_sys-$(CONFIG_THERMAL_GOV_BANG_BANG) += gov_bang_bang.o
-thermal_sys-$(CONFIG_THERMAL_GOV_STEP_WISE) += step_wise.o
-thermal_sys-$(CONFIG_THERMAL_GOV_USER_SPACE) += user_space.o
-thermal_sys-$(CONFIG_THERMAL_GOV_POWER_ALLOCATOR) += power_allocator.o
+thermal_sys-$(CONFIG_THERMAL_GOV_STEP_WISE) += gov_step_wise.o
+thermal_sys-$(CONFIG_THERMAL_GOV_USER_SPACE) += gov_user_space.o
+thermal_sys-$(CONFIG_THERMAL_GOV_POWER_ALLOCATOR) += gov_power_allocator.o
# cpufreq cooling
thermal_sys-$(CONFIG_CPU_FREQ_THERMAL) += cpufreq_cooling.o
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * fair_share.c - A simple weight based Thermal governor
- *
- * Copyright (C) 2012 Intel Corp
- * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- */
-
-#include <linux/thermal.h>
-#include <trace/events/thermal.h>
-
-#include "thermal_core.h"
-
-/**
- * get_trip_level: - obtains the current trip level for a zone
- * @tz: thermal zone device
- */
-static int get_trip_level(struct thermal_zone_device *tz)
-{
- int count = 0;
- int trip_temp;
- enum thermal_trip_type trip_type;
-
- if (tz->trips == 0 || !tz->ops->get_trip_temp)
- return 0;
-
- for (count = 0; count < tz->trips; count++) {
- tz->ops->get_trip_temp(tz, count, &trip_temp);
- if (tz->temperature < trip_temp)
- break;
- }
-
- /*
- * count > 0 only if temperature is greater than first trip
- * point, in which case, trip_point = count - 1
- */
- if (count > 0) {
- tz->ops->get_trip_type(tz, count - 1, &trip_type);
- trace_thermal_zone_trip(tz, count - 1, trip_type);
- }
-
- return count;
-}
-
-static long get_target_state(struct thermal_zone_device *tz,
- struct thermal_cooling_device *cdev, int percentage, int level)
-{
- unsigned long max_state;
-
- cdev->ops->get_max_state(cdev, &max_state);
-
- return (long)(percentage * level * max_state) / (100 * tz->trips);
-}
-
-/**
- * fair_share_throttle - throttles devices associated with the given zone
- * @tz: thermal_zone_device
- * @trip: trip point index
- *
- * Throttling Logic: This uses three parameters to calculate the new
- * throttle state of the cooling devices associated with the given zone.
- *
- * Parameters used for Throttling:
- * P1. max_state: Maximum throttle state exposed by the cooling device.
- * P2. percentage[i]/100:
- * How 'effective' the 'i'th device is, in cooling the given zone.
- * P3. cur_trip_level/max_no_of_trips:
- * This describes the extent to which the devices should be throttled.
- * We do not want to throttle too much when we trip a lower temperature,
- * whereas the throttling is at full swing if we trip critical levels.
- * (Heavily assumes the trip points are in ascending order)
- * new_state of cooling device = P3 * P2 * P1
- */
-static int fair_share_throttle(struct thermal_zone_device *tz, int trip)
-{
- struct thermal_instance *instance;
- int total_weight = 0;
- int total_instance = 0;
- int cur_trip_level = get_trip_level(tz);
-
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- if (instance->trip != trip)
- continue;
-
- total_weight += instance->weight;
- total_instance++;
- }
-
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- int percentage;
- struct thermal_cooling_device *cdev = instance->cdev;
-
- if (instance->trip != trip)
- continue;
-
- if (!total_weight)
- percentage = 100 / total_instance;
- else
- percentage = (instance->weight * 100) / total_weight;
-
- instance->target = get_target_state(tz, cdev, percentage,
- cur_trip_level);
-
- mutex_lock(&instance->cdev->lock);
- instance->cdev->updated = false;
- mutex_unlock(&instance->cdev->lock);
- thermal_cdev_update(cdev);
- }
- return 0;
-}
-
-static struct thermal_governor thermal_gov_fair_share = {
- .name = "fair_share",
- .throttle = fair_share_throttle,
-};
-THERMAL_GOVERNOR_DECLARE(thermal_gov_fair_share);
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * fair_share.c - A simple weight based Thermal governor
+ *
+ * Copyright (C) 2012 Intel Corp
+ * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/thermal.h>
+#include <trace/events/thermal.h>
+
+#include "thermal_core.h"
+
+/**
+ * get_trip_level: - obtains the current trip level for a zone
+ * @tz: thermal zone device
+ */
+static int get_trip_level(struct thermal_zone_device *tz)
+{
+ int count = 0;
+ int trip_temp;
+ enum thermal_trip_type trip_type;
+
+ if (tz->trips == 0 || !tz->ops->get_trip_temp)
+ return 0;
+
+ for (count = 0; count < tz->trips; count++) {
+ tz->ops->get_trip_temp(tz, count, &trip_temp);
+ if (tz->temperature < trip_temp)
+ break;
+ }
+
+ /*
+ * count > 0 only if temperature is greater than first trip
+ * point, in which case, trip_point = count - 1
+ */
+ if (count > 0) {
+ tz->ops->get_trip_type(tz, count - 1, &trip_type);
+ trace_thermal_zone_trip(tz, count - 1, trip_type);
+ }
+
+ return count;
+}
+
+static long get_target_state(struct thermal_zone_device *tz,
+ struct thermal_cooling_device *cdev, int percentage, int level)
+{
+ unsigned long max_state;
+
+ cdev->ops->get_max_state(cdev, &max_state);
+
+ return (long)(percentage * level * max_state) / (100 * tz->trips);
+}
+
+/**
+ * fair_share_throttle - throttles devices associated with the given zone
+ * @tz: thermal_zone_device
+ * @trip: trip point index
+ *
+ * Throttling Logic: This uses three parameters to calculate the new
+ * throttle state of the cooling devices associated with the given zone.
+ *
+ * Parameters used for Throttling:
+ * P1. max_state: Maximum throttle state exposed by the cooling device.
+ * P2. percentage[i]/100:
+ * How 'effective' the 'i'th device is, in cooling the given zone.
+ * P3. cur_trip_level/max_no_of_trips:
+ * This describes the extent to which the devices should be throttled.
+ * We do not want to throttle too much when we trip a lower temperature,
+ * whereas the throttling is at full swing if we trip critical levels.
+ * (Heavily assumes the trip points are in ascending order)
+ * new_state of cooling device = P3 * P2 * P1
+ */
+static int fair_share_throttle(struct thermal_zone_device *tz, int trip)
+{
+ struct thermal_instance *instance;
+ int total_weight = 0;
+ int total_instance = 0;
+ int cur_trip_level = get_trip_level(tz);
+
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ if (instance->trip != trip)
+ continue;
+
+ total_weight += instance->weight;
+ total_instance++;
+ }
+
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ int percentage;
+ struct thermal_cooling_device *cdev = instance->cdev;
+
+ if (instance->trip != trip)
+ continue;
+
+ if (!total_weight)
+ percentage = 100 / total_instance;
+ else
+ percentage = (instance->weight * 100) / total_weight;
+
+ instance->target = get_target_state(tz, cdev, percentage,
+ cur_trip_level);
+
+ mutex_lock(&instance->cdev->lock);
+ instance->cdev->updated = false;
+ mutex_unlock(&instance->cdev->lock);
+ thermal_cdev_update(cdev);
+ }
+ return 0;
+}
+
+static struct thermal_governor thermal_gov_fair_share = {
+ .name = "fair_share",
+ .throttle = fair_share_throttle,
+};
+THERMAL_GOVERNOR_DECLARE(thermal_gov_fair_share);
--- /dev/null
+/*
+ * A power allocator to manage temperature
+ *
+ * Copyright (C) 2014 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) "Power allocator: " fmt
+
+#include <linux/rculist.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/thermal_power_allocator.h>
+
+#include "thermal_core.h"
+
+#define INVALID_TRIP -1
+
+#define FRAC_BITS 10
+#define int_to_frac(x) ((x) << FRAC_BITS)
+#define frac_to_int(x) ((x) >> FRAC_BITS)
+
+/**
+ * mul_frac() - multiply two fixed-point numbers
+ * @x: first multiplicand
+ * @y: second multiplicand
+ *
+ * Return: the result of multiplying two fixed-point numbers. The
+ * result is also a fixed-point number.
+ */
+static inline s64 mul_frac(s64 x, s64 y)
+{
+ return (x * y) >> FRAC_BITS;
+}
+
+/**
+ * div_frac() - divide two fixed-point numbers
+ * @x: the dividend
+ * @y: the divisor
+ *
+ * Return: the result of dividing two fixed-point numbers. The
+ * result is also a fixed-point number.
+ */
+static inline s64 div_frac(s64 x, s64 y)
+{
+ return div_s64(x << FRAC_BITS, y);
+}
+
+/**
+ * struct power_allocator_params - parameters for the power allocator governor
+ * @allocated_tzp: whether we have allocated tzp for this thermal zone and
+ * it needs to be freed on unbind
+ * @err_integral: accumulated error in the PID controller.
+ * @prev_err: error in the previous iteration of the PID controller.
+ * Used to calculate the derivative term.
+ * @trip_switch_on: first passive trip point of the thermal zone. The
+ * governor switches on when this trip point is crossed.
+ * If the thermal zone only has one passive trip point,
+ * @trip_switch_on should be INVALID_TRIP.
+ * @trip_max_desired_temperature: last passive trip point of the thermal
+ * zone. The temperature we are
+ * controlling for.
+ */
+struct power_allocator_params {
+ bool allocated_tzp;
+ s64 err_integral;
+ s32 prev_err;
+ int trip_switch_on;
+ int trip_max_desired_temperature;
+};
+
+/**
+ * estimate_sustainable_power() - Estimate the sustainable power of a thermal zone
+ * @tz: thermal zone we are operating in
+ *
+ * For thermal zones that don't provide a sustainable_power in their
+ * thermal_zone_params, estimate one. Calculate it using the minimum
+ * power of all the cooling devices as that gives a valid value that
+ * can give some degree of functionality. For optimal performance of
+ * this governor, provide a sustainable_power in the thermal zone's
+ * thermal_zone_params.
+ */
+static u32 estimate_sustainable_power(struct thermal_zone_device *tz)
+{
+ u32 sustainable_power = 0;
+ struct thermal_instance *instance;
+ struct power_allocator_params *params = tz->governor_data;
+
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ struct thermal_cooling_device *cdev = instance->cdev;
+ u32 min_power;
+
+ if (instance->trip != params->trip_max_desired_temperature)
+ continue;
+
+ if (power_actor_get_min_power(cdev, tz, &min_power))
+ continue;
+
+ sustainable_power += min_power;
+ }
+
+ return sustainable_power;
+}
+
+/**
+ * estimate_pid_constants() - Estimate the constants for the PID controller
+ * @tz: thermal zone for which to estimate the constants
+ * @sustainable_power: sustainable power for the thermal zone
+ * @trip_switch_on: trip point number for the switch on temperature
+ * @control_temp: target temperature for the power allocator governor
+ * @force: whether to force the update of the constants
+ *
+ * This function is used to update the estimation of the PID
+ * controller constants in struct thermal_zone_parameters.
+ * Sustainable power is provided in case it was estimated. The
+ * estimated sustainable_power should not be stored in the
+ * thermal_zone_parameters so it has to be passed explicitly to this
+ * function.
+ *
+ * If @force is not set, the values in the thermal zone's parameters
+ * are preserved if they are not zero. If @force is set, the values
+ * in thermal zone's parameters are overwritten.
+ */
+static void estimate_pid_constants(struct thermal_zone_device *tz,
+ u32 sustainable_power, int trip_switch_on,
+ int control_temp, bool force)
+{
+ int ret;
+ int switch_on_temp;
+ u32 temperature_threshold;
+
+ ret = tz->ops->get_trip_temp(tz, trip_switch_on, &switch_on_temp);
+ if (ret)
+ switch_on_temp = 0;
+
+ temperature_threshold = control_temp - switch_on_temp;
+ /*
+ * estimate_pid_constants() tries to find appropriate default
+ * values for thermal zones that don't provide them. If a
+ * system integrator has configured a thermal zone with two
+ * passive trip points at the same temperature, that person
+ * hasn't put any effort to set up the thermal zone properly
+ * so just give up.
+ */
+ if (!temperature_threshold)
+ return;
+
+ if (!tz->tzp->k_po || force)
+ tz->tzp->k_po = int_to_frac(sustainable_power) /
+ temperature_threshold;
+
+ if (!tz->tzp->k_pu || force)
+ tz->tzp->k_pu = int_to_frac(2 * sustainable_power) /
+ temperature_threshold;
+
+ if (!tz->tzp->k_i || force)
+ tz->tzp->k_i = int_to_frac(10) / 1000;
+ /*
+ * The default for k_d and integral_cutoff is 0, so we can
+ * leave them as they are.
+ */
+}
+
+/**
+ * pid_controller() - PID controller
+ * @tz: thermal zone we are operating in
+ * @control_temp: the target temperature in millicelsius
+ * @max_allocatable_power: maximum allocatable power for this thermal zone
+ *
+ * This PID controller increases the available power budget so that the
+ * temperature of the thermal zone gets as close as possible to
+ * @control_temp and limits the power if it exceeds it. k_po is the
+ * proportional term when we are overshooting, k_pu is the
+ * proportional term when we are undershooting. integral_cutoff is a
+ * threshold below which we stop accumulating the error. The
+ * accumulated error is only valid if the requested power will make
+ * the system warmer. If the system is mostly idle, there's no point
+ * in accumulating positive error.
+ *
+ * Return: The power budget for the next period.
+ */
+static u32 pid_controller(struct thermal_zone_device *tz,
+ int control_temp,
+ u32 max_allocatable_power)
+{
+ s64 p, i, d, power_range;
+ s32 err, max_power_frac;
+ u32 sustainable_power;
+ struct power_allocator_params *params = tz->governor_data;
+
+ max_power_frac = int_to_frac(max_allocatable_power);
+
+ if (tz->tzp->sustainable_power) {
+ sustainable_power = tz->tzp->sustainable_power;
+ } else {
+ sustainable_power = estimate_sustainable_power(tz);
+ estimate_pid_constants(tz, sustainable_power,
+ params->trip_switch_on, control_temp,
+ true);
+ }
+
+ err = control_temp - tz->temperature;
+ err = int_to_frac(err);
+
+ /* Calculate the proportional term */
+ p = mul_frac(err < 0 ? tz->tzp->k_po : tz->tzp->k_pu, err);
+
+ /*
+ * Calculate the integral term
+ *
+ * if the error is less than cut off allow integration (but
+ * the integral is limited to max power)
+ */
+ i = mul_frac(tz->tzp->k_i, params->err_integral);
+
+ if (err < int_to_frac(tz->tzp->integral_cutoff)) {
+ s64 i_next = i + mul_frac(tz->tzp->k_i, err);
+
+ if (abs(i_next) < max_power_frac) {
+ i = i_next;
+ params->err_integral += err;
+ }
+ }
+
+ /*
+ * Calculate the derivative term
+ *
+ * We do err - prev_err, so with a positive k_d, a decreasing
+ * error (i.e. driving closer to the line) results in less
+ * power being applied, slowing down the controller)
+ */
+ d = mul_frac(tz->tzp->k_d, err - params->prev_err);
+ d = div_frac(d, tz->passive_delay);
+ params->prev_err = err;
+
+ power_range = p + i + d;
+
+ /* feed-forward the known sustainable dissipatable power */
+ power_range = sustainable_power + frac_to_int(power_range);
+
+ power_range = clamp(power_range, (s64)0, (s64)max_allocatable_power);
+
+ trace_thermal_power_allocator_pid(tz, frac_to_int(err),
+ frac_to_int(params->err_integral),
+ frac_to_int(p), frac_to_int(i),
+ frac_to_int(d), power_range);
+
+ return power_range;
+}
+
+/**
+ * divvy_up_power() - divvy the allocated power between the actors
+ * @req_power: each actor's requested power
+ * @max_power: each actor's maximum available power
+ * @num_actors: size of the @req_power, @max_power and @granted_power's array
+ * @total_req_power: sum of @req_power
+ * @power_range: total allocated power
+ * @granted_power: output array: each actor's granted power
+ * @extra_actor_power: an appropriately sized array to be used in the
+ * function as temporary storage of the extra power given
+ * to the actors
+ *
+ * This function divides the total allocated power (@power_range)
+ * fairly between the actors. It first tries to give each actor a
+ * share of the @power_range according to how much power it requested
+ * compared to the rest of the actors. For example, if only one actor
+ * requests power, then it receives all the @power_range. If
+ * three actors each requests 1mW, each receives a third of the
+ * @power_range.
+ *
+ * If any actor received more than their maximum power, then that
+ * surplus is re-divvied among the actors based on how far they are
+ * from their respective maximums.
+ *
+ * Granted power for each actor is written to @granted_power, which
+ * should've been allocated by the calling function.
+ */
+static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
+ u32 total_req_power, u32 power_range,
+ u32 *granted_power, u32 *extra_actor_power)
+{
+ u32 extra_power, capped_extra_power;
+ int i;
+
+ /*
+ * Prevent division by 0 if none of the actors request power.
+ */
+ if (!total_req_power)
+ total_req_power = 1;
+
+ capped_extra_power = 0;
+ extra_power = 0;
+ for (i = 0; i < num_actors; i++) {
+ u64 req_range = (u64)req_power[i] * power_range;
+
+ granted_power[i] = DIV_ROUND_CLOSEST_ULL(req_range,
+ total_req_power);
+
+ if (granted_power[i] > max_power[i]) {
+ extra_power += granted_power[i] - max_power[i];
+ granted_power[i] = max_power[i];
+ }
+
+ extra_actor_power[i] = max_power[i] - granted_power[i];
+ capped_extra_power += extra_actor_power[i];
+ }
+
+ if (!extra_power)
+ return;
+
+ /*
+ * Re-divvy the reclaimed extra among actors based on
+ * how far they are from the max
+ */
+ extra_power = min(extra_power, capped_extra_power);
+ if (capped_extra_power > 0)
+ for (i = 0; i < num_actors; i++)
+ granted_power[i] += (extra_actor_power[i] *
+ extra_power) / capped_extra_power;
+}
+
+static int allocate_power(struct thermal_zone_device *tz,
+ int control_temp)
+{
+ struct thermal_instance *instance;
+ struct power_allocator_params *params = tz->governor_data;
+ u32 *req_power, *max_power, *granted_power, *extra_actor_power;
+ u32 *weighted_req_power;
+ u32 total_req_power, max_allocatable_power, total_weighted_req_power;
+ u32 total_granted_power, power_range;
+ int i, num_actors, total_weight, ret = 0;
+ int trip_max_desired_temperature = params->trip_max_desired_temperature;
+
+ mutex_lock(&tz->lock);
+
+ num_actors = 0;
+ total_weight = 0;
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ if ((instance->trip == trip_max_desired_temperature) &&
+ cdev_is_power_actor(instance->cdev)) {
+ num_actors++;
+ total_weight += instance->weight;
+ }
+ }
+
+ if (!num_actors) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ /*
+ * We need to allocate five arrays of the same size:
+ * req_power, max_power, granted_power, extra_actor_power and
+ * weighted_req_power. They are going to be needed until this
+ * function returns. Allocate them all in one go to simplify
+ * the allocation and deallocation logic.
+ */
+ BUILD_BUG_ON(sizeof(*req_power) != sizeof(*max_power));
+ BUILD_BUG_ON(sizeof(*req_power) != sizeof(*granted_power));
+ BUILD_BUG_ON(sizeof(*req_power) != sizeof(*extra_actor_power));
+ BUILD_BUG_ON(sizeof(*req_power) != sizeof(*weighted_req_power));
+ req_power = kcalloc(num_actors * 5, sizeof(*req_power), GFP_KERNEL);
+ if (!req_power) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ max_power = &req_power[num_actors];
+ granted_power = &req_power[2 * num_actors];
+ extra_actor_power = &req_power[3 * num_actors];
+ weighted_req_power = &req_power[4 * num_actors];
+
+ i = 0;
+ total_weighted_req_power = 0;
+ total_req_power = 0;
+ max_allocatable_power = 0;
+
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ int weight;
+ struct thermal_cooling_device *cdev = instance->cdev;
+
+ if (instance->trip != trip_max_desired_temperature)
+ continue;
+
+ if (!cdev_is_power_actor(cdev))
+ continue;
+
+ if (cdev->ops->get_requested_power(cdev, tz, &req_power[i]))
+ continue;
+
+ if (!total_weight)
+ weight = 1 << FRAC_BITS;
+ else
+ weight = instance->weight;
+
+ weighted_req_power[i] = frac_to_int(weight * req_power[i]);
+
+ if (power_actor_get_max_power(cdev, tz, &max_power[i]))
+ continue;
+
+ total_req_power += req_power[i];
+ max_allocatable_power += max_power[i];
+ total_weighted_req_power += weighted_req_power[i];
+
+ i++;
+ }
+
+ power_range = pid_controller(tz, control_temp, max_allocatable_power);
+
+ divvy_up_power(weighted_req_power, max_power, num_actors,
+ total_weighted_req_power, power_range, granted_power,
+ extra_actor_power);
+
+ total_granted_power = 0;
+ i = 0;
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ if (instance->trip != trip_max_desired_temperature)
+ continue;
+
+ if (!cdev_is_power_actor(instance->cdev))
+ continue;
+
+ power_actor_set_power(instance->cdev, instance,
+ granted_power[i]);
+ total_granted_power += granted_power[i];
+
+ i++;
+ }
+
+ trace_thermal_power_allocator(tz, req_power, total_req_power,
+ granted_power, total_granted_power,
+ num_actors, power_range,
+ max_allocatable_power, tz->temperature,
+ control_temp - tz->temperature);
+
+ kfree(req_power);
+unlock:
+ mutex_unlock(&tz->lock);
+
+ return ret;
+}
+
+/**
+ * get_governor_trips() - get the number of the two trip points that are key for this governor
+ * @tz: thermal zone to operate on
+ * @params: pointer to private data for this governor
+ *
+ * The power allocator governor works optimally with two trips points:
+ * a "switch on" trip point and a "maximum desired temperature". These
+ * are defined as the first and last passive trip points.
+ *
+ * If there is only one trip point, then that's considered to be the
+ * "maximum desired temperature" trip point and the governor is always
+ * on. If there are no passive or active trip points, then the
+ * governor won't do anything. In fact, its throttle function
+ * won't be called at all.
+ */
+static void get_governor_trips(struct thermal_zone_device *tz,
+ struct power_allocator_params *params)
+{
+ int i, last_active, last_passive;
+ bool found_first_passive;
+
+ found_first_passive = false;
+ last_active = INVALID_TRIP;
+ last_passive = INVALID_TRIP;
+
+ for (i = 0; i < tz->trips; i++) {
+ enum thermal_trip_type type;
+ int ret;
+
+ ret = tz->ops->get_trip_type(tz, i, &type);
+ if (ret) {
+ dev_warn(&tz->device,
+ "Failed to get trip point %d type: %d\n", i,
+ ret);
+ continue;
+ }
+
+ if (type == THERMAL_TRIP_PASSIVE) {
+ if (!found_first_passive) {
+ params->trip_switch_on = i;
+ found_first_passive = true;
+ } else {
+ last_passive = i;
+ }
+ } else if (type == THERMAL_TRIP_ACTIVE) {
+ last_active = i;
+ } else {
+ break;
+ }
+ }
+
+ if (last_passive != INVALID_TRIP) {
+ params->trip_max_desired_temperature = last_passive;
+ } else if (found_first_passive) {
+ params->trip_max_desired_temperature = params->trip_switch_on;
+ params->trip_switch_on = INVALID_TRIP;
+ } else {
+ params->trip_switch_on = INVALID_TRIP;
+ params->trip_max_desired_temperature = last_active;
+ }
+}
+
+static void reset_pid_controller(struct power_allocator_params *params)
+{
+ params->err_integral = 0;
+ params->prev_err = 0;
+}
+
+static void allow_maximum_power(struct thermal_zone_device *tz)
+{
+ struct thermal_instance *instance;
+ struct power_allocator_params *params = tz->governor_data;
+
+ mutex_lock(&tz->lock);
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ if ((instance->trip != params->trip_max_desired_temperature) ||
+ (!cdev_is_power_actor(instance->cdev)))
+ continue;
+
+ instance->target = 0;
+ mutex_lock(&instance->cdev->lock);
+ instance->cdev->updated = false;
+ mutex_unlock(&instance->cdev->lock);
+ thermal_cdev_update(instance->cdev);
+ }
+ mutex_unlock(&tz->lock);
+}
+
+/**
+ * power_allocator_bind() - bind the power_allocator governor to a thermal zone
+ * @tz: thermal zone to bind it to
+ *
+ * Initialize the PID controller parameters and bind it to the thermal
+ * zone.
+ *
+ * Return: 0 on success, or -ENOMEM if we ran out of memory.
+ */
+static int power_allocator_bind(struct thermal_zone_device *tz)
+{
+ int ret;
+ struct power_allocator_params *params;
+ int control_temp;
+
+ params = kzalloc(sizeof(*params), GFP_KERNEL);
+ if (!params)
+ return -ENOMEM;
+
+ if (!tz->tzp) {
+ tz->tzp = kzalloc(sizeof(*tz->tzp), GFP_KERNEL);
+ if (!tz->tzp) {
+ ret = -ENOMEM;
+ goto free_params;
+ }
+
+ params->allocated_tzp = true;
+ }
+
+ if (!tz->tzp->sustainable_power)
+ dev_warn(&tz->device, "power_allocator: sustainable_power will be estimated\n");
+
+ get_governor_trips(tz, params);
+
+ if (tz->trips > 0) {
+ ret = tz->ops->get_trip_temp(tz,
+ params->trip_max_desired_temperature,
+ &control_temp);
+ if (!ret)
+ estimate_pid_constants(tz, tz->tzp->sustainable_power,
+ params->trip_switch_on,
+ control_temp, false);
+ }
+
+ reset_pid_controller(params);
+
+ tz->governor_data = params;
+
+ return 0;
+
+free_params:
+ kfree(params);
+
+ return ret;
+}
+
+static void power_allocator_unbind(struct thermal_zone_device *tz)
+{
+ struct power_allocator_params *params = tz->governor_data;
+
+ dev_dbg(&tz->device, "Unbinding from thermal zone %d\n", tz->id);
+
+ if (params->allocated_tzp) {
+ kfree(tz->tzp);
+ tz->tzp = NULL;
+ }
+
+ kfree(tz->governor_data);
+ tz->governor_data = NULL;
+}
+
+static int power_allocator_throttle(struct thermal_zone_device *tz, int trip)
+{
+ int ret;
+ int switch_on_temp, control_temp;
+ struct power_allocator_params *params = tz->governor_data;
+
+ /*
+ * We get called for every trip point but we only need to do
+ * our calculations once
+ */
+ if (trip != params->trip_max_desired_temperature)
+ return 0;
+
+ ret = tz->ops->get_trip_temp(tz, params->trip_switch_on,
+ &switch_on_temp);
+ if (!ret && (tz->temperature < switch_on_temp)) {
+ tz->passive = 0;
+ reset_pid_controller(params);
+ allow_maximum_power(tz);
+ return 0;
+ }
+
+ tz->passive = 1;
+
+ ret = tz->ops->get_trip_temp(tz, params->trip_max_desired_temperature,
+ &control_temp);
+ if (ret) {
+ dev_warn(&tz->device,
+ "Failed to get the maximum desired temperature: %d\n",
+ ret);
+ return ret;
+ }
+
+ return allocate_power(tz, control_temp);
+}
+
+static struct thermal_governor thermal_gov_power_allocator = {
+ .name = "power_allocator",
+ .bind_to_tz = power_allocator_bind,
+ .unbind_from_tz = power_allocator_unbind,
+ .throttle = power_allocator_throttle,
+};
+THERMAL_GOVERNOR_DECLARE(thermal_gov_power_allocator);
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * step_wise.c - A step-by-step Thermal throttling governor
+ *
+ * Copyright (C) 2012 Intel Corp
+ * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/thermal.h>
+#include <trace/events/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, do nothing
+ * 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,
+ * deactivate the thermal instance
+ */
+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;
+ unsigned long next_target;
+
+ /*
+ * We keep this instance the way it is by default.
+ * Otherwise, we use the current state of the
+ * cdev in use to determine the next_target.
+ */
+ cdev->ops->get_cur_state(cdev, &cur_state);
+ next_target = instance->target;
+ dev_dbg(&cdev->device, "cur_state=%ld\n", cur_state);
+
+ if (!instance->initialized) {
+ if (throttle) {
+ next_target = (cur_state + 1) >= instance->upper ?
+ instance->upper :
+ ((cur_state + 1) < instance->lower ?
+ instance->lower : (cur_state + 1));
+ } else {
+ next_target = THERMAL_NO_TARGET;
+ }
+
+ return next_target;
+ }
+
+ switch (trend) {
+ case THERMAL_TREND_RAISING:
+ if (throttle) {
+ next_target = cur_state < instance->upper ?
+ (cur_state + 1) : instance->upper;
+ if (next_target < instance->lower)
+ next_target = instance->lower;
+ }
+ break;
+ case THERMAL_TREND_RAISE_FULL:
+ if (throttle)
+ next_target = instance->upper;
+ break;
+ case THERMAL_TREND_DROPPING:
+ if (cur_state <= instance->lower) {
+ if (!throttle)
+ next_target = THERMAL_NO_TARGET;
+ } else {
+ if (!throttle) {
+ next_target = cur_state - 1;
+ if (next_target > instance->upper)
+ next_target = instance->upper;
+ }
+ }
+ break;
+ case THERMAL_TREND_DROP_FULL:
+ if (cur_state == instance->lower) {
+ if (!throttle)
+ next_target = THERMAL_NO_TARGET;
+ } else
+ next_target = instance->lower;
+ break;
+ default:
+ break;
+ }
+
+ return next_target;
+}
+
+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)
+{
+ int 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;
+ trace_thermal_zone_trip(tz, trip, trip_type);
+ }
+
+ dev_dbg(&tz->device, "Trip%d[type=%d,temp=%d]: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);
+
+ if (instance->initialized && old_target == instance->target)
+ continue;
+
+ /* 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->initialized = true;
+ mutex_lock(&instance->cdev->lock);
+ instance->cdev->updated = false; /* cdev needs update */
+ mutex_unlock(&instance->cdev->lock);
+ }
+
+ mutex_unlock(&tz->lock);
+}
+
+/**
+ * step_wise_throttle - throttles devices associated with the given zone
+ * @tz: thermal_zone_device
+ * @trip: trip point index
+ *
+ * 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,
+};
+THERMAL_GOVERNOR_DECLARE(thermal_gov_step_wise);
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * user_space.c - A simple user space Thermal events notifier
+ *
+ * Copyright (C) 2012 Intel Corp
+ * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+/**
+ * notify_user_space - Notifies user space about thermal events
+ * @tz: thermal_zone_device
+ * @trip: trip point index
+ *
+ * This function notifies the user space through UEvents.
+ */
+static int notify_user_space(struct thermal_zone_device *tz, int trip)
+{
+ char *thermal_prop[5];
+ int i;
+
+ mutex_lock(&tz->lock);
+ thermal_prop[0] = kasprintf(GFP_KERNEL, "NAME=%s", tz->type);
+ thermal_prop[1] = kasprintf(GFP_KERNEL, "TEMP=%d", tz->temperature);
+ thermal_prop[2] = kasprintf(GFP_KERNEL, "TRIP=%d", trip);
+ thermal_prop[3] = kasprintf(GFP_KERNEL, "EVENT=%d", tz->notify_event);
+ thermal_prop[4] = NULL;
+ kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, thermal_prop);
+ for (i = 0; i < 4; ++i)
+ kfree(thermal_prop[i]);
+ mutex_unlock(&tz->lock);
+ return 0;
+}
+
+static struct thermal_governor thermal_gov_user_space = {
+ .name = "user_space",
+ .throttle = notify_user_space,
+};
+THERMAL_GOVERNOR_DECLARE(thermal_gov_user_space);
+++ /dev/null
-/*
- * A power allocator to manage temperature
- *
- * Copyright (C) 2014 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#define pr_fmt(fmt) "Power allocator: " fmt
-
-#include <linux/rculist.h>
-#include <linux/slab.h>
-#include <linux/thermal.h>
-
-#define CREATE_TRACE_POINTS
-#include <trace/events/thermal_power_allocator.h>
-
-#include "thermal_core.h"
-
-#define INVALID_TRIP -1
-
-#define FRAC_BITS 10
-#define int_to_frac(x) ((x) << FRAC_BITS)
-#define frac_to_int(x) ((x) >> FRAC_BITS)
-
-/**
- * mul_frac() - multiply two fixed-point numbers
- * @x: first multiplicand
- * @y: second multiplicand
- *
- * Return: the result of multiplying two fixed-point numbers. The
- * result is also a fixed-point number.
- */
-static inline s64 mul_frac(s64 x, s64 y)
-{
- return (x * y) >> FRAC_BITS;
-}
-
-/**
- * div_frac() - divide two fixed-point numbers
- * @x: the dividend
- * @y: the divisor
- *
- * Return: the result of dividing two fixed-point numbers. The
- * result is also a fixed-point number.
- */
-static inline s64 div_frac(s64 x, s64 y)
-{
- return div_s64(x << FRAC_BITS, y);
-}
-
-/**
- * struct power_allocator_params - parameters for the power allocator governor
- * @allocated_tzp: whether we have allocated tzp for this thermal zone and
- * it needs to be freed on unbind
- * @err_integral: accumulated error in the PID controller.
- * @prev_err: error in the previous iteration of the PID controller.
- * Used to calculate the derivative term.
- * @trip_switch_on: first passive trip point of the thermal zone. The
- * governor switches on when this trip point is crossed.
- * If the thermal zone only has one passive trip point,
- * @trip_switch_on should be INVALID_TRIP.
- * @trip_max_desired_temperature: last passive trip point of the thermal
- * zone. The temperature we are
- * controlling for.
- */
-struct power_allocator_params {
- bool allocated_tzp;
- s64 err_integral;
- s32 prev_err;
- int trip_switch_on;
- int trip_max_desired_temperature;
-};
-
-/**
- * estimate_sustainable_power() - Estimate the sustainable power of a thermal zone
- * @tz: thermal zone we are operating in
- *
- * For thermal zones that don't provide a sustainable_power in their
- * thermal_zone_params, estimate one. Calculate it using the minimum
- * power of all the cooling devices as that gives a valid value that
- * can give some degree of functionality. For optimal performance of
- * this governor, provide a sustainable_power in the thermal zone's
- * thermal_zone_params.
- */
-static u32 estimate_sustainable_power(struct thermal_zone_device *tz)
-{
- u32 sustainable_power = 0;
- struct thermal_instance *instance;
- struct power_allocator_params *params = tz->governor_data;
-
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- struct thermal_cooling_device *cdev = instance->cdev;
- u32 min_power;
-
- if (instance->trip != params->trip_max_desired_temperature)
- continue;
-
- if (power_actor_get_min_power(cdev, tz, &min_power))
- continue;
-
- sustainable_power += min_power;
- }
-
- return sustainable_power;
-}
-
-/**
- * estimate_pid_constants() - Estimate the constants for the PID controller
- * @tz: thermal zone for which to estimate the constants
- * @sustainable_power: sustainable power for the thermal zone
- * @trip_switch_on: trip point number for the switch on temperature
- * @control_temp: target temperature for the power allocator governor
- * @force: whether to force the update of the constants
- *
- * This function is used to update the estimation of the PID
- * controller constants in struct thermal_zone_parameters.
- * Sustainable power is provided in case it was estimated. The
- * estimated sustainable_power should not be stored in the
- * thermal_zone_parameters so it has to be passed explicitly to this
- * function.
- *
- * If @force is not set, the values in the thermal zone's parameters
- * are preserved if they are not zero. If @force is set, the values
- * in thermal zone's parameters are overwritten.
- */
-static void estimate_pid_constants(struct thermal_zone_device *tz,
- u32 sustainable_power, int trip_switch_on,
- int control_temp, bool force)
-{
- int ret;
- int switch_on_temp;
- u32 temperature_threshold;
-
- ret = tz->ops->get_trip_temp(tz, trip_switch_on, &switch_on_temp);
- if (ret)
- switch_on_temp = 0;
-
- temperature_threshold = control_temp - switch_on_temp;
- /*
- * estimate_pid_constants() tries to find appropriate default
- * values for thermal zones that don't provide them. If a
- * system integrator has configured a thermal zone with two
- * passive trip points at the same temperature, that person
- * hasn't put any effort to set up the thermal zone properly
- * so just give up.
- */
- if (!temperature_threshold)
- return;
-
- if (!tz->tzp->k_po || force)
- tz->tzp->k_po = int_to_frac(sustainable_power) /
- temperature_threshold;
-
- if (!tz->tzp->k_pu || force)
- tz->tzp->k_pu = int_to_frac(2 * sustainable_power) /
- temperature_threshold;
-
- if (!tz->tzp->k_i || force)
- tz->tzp->k_i = int_to_frac(10) / 1000;
- /*
- * The default for k_d and integral_cutoff is 0, so we can
- * leave them as they are.
- */
-}
-
-/**
- * pid_controller() - PID controller
- * @tz: thermal zone we are operating in
- * @control_temp: the target temperature in millicelsius
- * @max_allocatable_power: maximum allocatable power for this thermal zone
- *
- * This PID controller increases the available power budget so that the
- * temperature of the thermal zone gets as close as possible to
- * @control_temp and limits the power if it exceeds it. k_po is the
- * proportional term when we are overshooting, k_pu is the
- * proportional term when we are undershooting. integral_cutoff is a
- * threshold below which we stop accumulating the error. The
- * accumulated error is only valid if the requested power will make
- * the system warmer. If the system is mostly idle, there's no point
- * in accumulating positive error.
- *
- * Return: The power budget for the next period.
- */
-static u32 pid_controller(struct thermal_zone_device *tz,
- int control_temp,
- u32 max_allocatable_power)
-{
- s64 p, i, d, power_range;
- s32 err, max_power_frac;
- u32 sustainable_power;
- struct power_allocator_params *params = tz->governor_data;
-
- max_power_frac = int_to_frac(max_allocatable_power);
-
- if (tz->tzp->sustainable_power) {
- sustainable_power = tz->tzp->sustainable_power;
- } else {
- sustainable_power = estimate_sustainable_power(tz);
- estimate_pid_constants(tz, sustainable_power,
- params->trip_switch_on, control_temp,
- true);
- }
-
- err = control_temp - tz->temperature;
- err = int_to_frac(err);
-
- /* Calculate the proportional term */
- p = mul_frac(err < 0 ? tz->tzp->k_po : tz->tzp->k_pu, err);
-
- /*
- * Calculate the integral term
- *
- * if the error is less than cut off allow integration (but
- * the integral is limited to max power)
- */
- i = mul_frac(tz->tzp->k_i, params->err_integral);
-
- if (err < int_to_frac(tz->tzp->integral_cutoff)) {
- s64 i_next = i + mul_frac(tz->tzp->k_i, err);
-
- if (abs(i_next) < max_power_frac) {
- i = i_next;
- params->err_integral += err;
- }
- }
-
- /*
- * Calculate the derivative term
- *
- * We do err - prev_err, so with a positive k_d, a decreasing
- * error (i.e. driving closer to the line) results in less
- * power being applied, slowing down the controller)
- */
- d = mul_frac(tz->tzp->k_d, err - params->prev_err);
- d = div_frac(d, tz->passive_delay);
- params->prev_err = err;
-
- power_range = p + i + d;
-
- /* feed-forward the known sustainable dissipatable power */
- power_range = sustainable_power + frac_to_int(power_range);
-
- power_range = clamp(power_range, (s64)0, (s64)max_allocatable_power);
-
- trace_thermal_power_allocator_pid(tz, frac_to_int(err),
- frac_to_int(params->err_integral),
- frac_to_int(p), frac_to_int(i),
- frac_to_int(d), power_range);
-
- return power_range;
-}
-
-/**
- * divvy_up_power() - divvy the allocated power between the actors
- * @req_power: each actor's requested power
- * @max_power: each actor's maximum available power
- * @num_actors: size of the @req_power, @max_power and @granted_power's array
- * @total_req_power: sum of @req_power
- * @power_range: total allocated power
- * @granted_power: output array: each actor's granted power
- * @extra_actor_power: an appropriately sized array to be used in the
- * function as temporary storage of the extra power given
- * to the actors
- *
- * This function divides the total allocated power (@power_range)
- * fairly between the actors. It first tries to give each actor a
- * share of the @power_range according to how much power it requested
- * compared to the rest of the actors. For example, if only one actor
- * requests power, then it receives all the @power_range. If
- * three actors each requests 1mW, each receives a third of the
- * @power_range.
- *
- * If any actor received more than their maximum power, then that
- * surplus is re-divvied among the actors based on how far they are
- * from their respective maximums.
- *
- * Granted power for each actor is written to @granted_power, which
- * should've been allocated by the calling function.
- */
-static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
- u32 total_req_power, u32 power_range,
- u32 *granted_power, u32 *extra_actor_power)
-{
- u32 extra_power, capped_extra_power;
- int i;
-
- /*
- * Prevent division by 0 if none of the actors request power.
- */
- if (!total_req_power)
- total_req_power = 1;
-
- capped_extra_power = 0;
- extra_power = 0;
- for (i = 0; i < num_actors; i++) {
- u64 req_range = (u64)req_power[i] * power_range;
-
- granted_power[i] = DIV_ROUND_CLOSEST_ULL(req_range,
- total_req_power);
-
- if (granted_power[i] > max_power[i]) {
- extra_power += granted_power[i] - max_power[i];
- granted_power[i] = max_power[i];
- }
-
- extra_actor_power[i] = max_power[i] - granted_power[i];
- capped_extra_power += extra_actor_power[i];
- }
-
- if (!extra_power)
- return;
-
- /*
- * Re-divvy the reclaimed extra among actors based on
- * how far they are from the max
- */
- extra_power = min(extra_power, capped_extra_power);
- if (capped_extra_power > 0)
- for (i = 0; i < num_actors; i++)
- granted_power[i] += (extra_actor_power[i] *
- extra_power) / capped_extra_power;
-}
-
-static int allocate_power(struct thermal_zone_device *tz,
- int control_temp)
-{
- struct thermal_instance *instance;
- struct power_allocator_params *params = tz->governor_data;
- u32 *req_power, *max_power, *granted_power, *extra_actor_power;
- u32 *weighted_req_power;
- u32 total_req_power, max_allocatable_power, total_weighted_req_power;
- u32 total_granted_power, power_range;
- int i, num_actors, total_weight, ret = 0;
- int trip_max_desired_temperature = params->trip_max_desired_temperature;
-
- mutex_lock(&tz->lock);
-
- num_actors = 0;
- total_weight = 0;
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- if ((instance->trip == trip_max_desired_temperature) &&
- cdev_is_power_actor(instance->cdev)) {
- num_actors++;
- total_weight += instance->weight;
- }
- }
-
- if (!num_actors) {
- ret = -ENODEV;
- goto unlock;
- }
-
- /*
- * We need to allocate five arrays of the same size:
- * req_power, max_power, granted_power, extra_actor_power and
- * weighted_req_power. They are going to be needed until this
- * function returns. Allocate them all in one go to simplify
- * the allocation and deallocation logic.
- */
- BUILD_BUG_ON(sizeof(*req_power) != sizeof(*max_power));
- BUILD_BUG_ON(sizeof(*req_power) != sizeof(*granted_power));
- BUILD_BUG_ON(sizeof(*req_power) != sizeof(*extra_actor_power));
- BUILD_BUG_ON(sizeof(*req_power) != sizeof(*weighted_req_power));
- req_power = kcalloc(num_actors * 5, sizeof(*req_power), GFP_KERNEL);
- if (!req_power) {
- ret = -ENOMEM;
- goto unlock;
- }
-
- max_power = &req_power[num_actors];
- granted_power = &req_power[2 * num_actors];
- extra_actor_power = &req_power[3 * num_actors];
- weighted_req_power = &req_power[4 * num_actors];
-
- i = 0;
- total_weighted_req_power = 0;
- total_req_power = 0;
- max_allocatable_power = 0;
-
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- int weight;
- struct thermal_cooling_device *cdev = instance->cdev;
-
- if (instance->trip != trip_max_desired_temperature)
- continue;
-
- if (!cdev_is_power_actor(cdev))
- continue;
-
- if (cdev->ops->get_requested_power(cdev, tz, &req_power[i]))
- continue;
-
- if (!total_weight)
- weight = 1 << FRAC_BITS;
- else
- weight = instance->weight;
-
- weighted_req_power[i] = frac_to_int(weight * req_power[i]);
-
- if (power_actor_get_max_power(cdev, tz, &max_power[i]))
- continue;
-
- total_req_power += req_power[i];
- max_allocatable_power += max_power[i];
- total_weighted_req_power += weighted_req_power[i];
-
- i++;
- }
-
- power_range = pid_controller(tz, control_temp, max_allocatable_power);
-
- divvy_up_power(weighted_req_power, max_power, num_actors,
- total_weighted_req_power, power_range, granted_power,
- extra_actor_power);
-
- total_granted_power = 0;
- i = 0;
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- if (instance->trip != trip_max_desired_temperature)
- continue;
-
- if (!cdev_is_power_actor(instance->cdev))
- continue;
-
- power_actor_set_power(instance->cdev, instance,
- granted_power[i]);
- total_granted_power += granted_power[i];
-
- i++;
- }
-
- trace_thermal_power_allocator(tz, req_power, total_req_power,
- granted_power, total_granted_power,
- num_actors, power_range,
- max_allocatable_power, tz->temperature,
- control_temp - tz->temperature);
-
- kfree(req_power);
-unlock:
- mutex_unlock(&tz->lock);
-
- return ret;
-}
-
-/**
- * get_governor_trips() - get the number of the two trip points that are key for this governor
- * @tz: thermal zone to operate on
- * @params: pointer to private data for this governor
- *
- * The power allocator governor works optimally with two trips points:
- * a "switch on" trip point and a "maximum desired temperature". These
- * are defined as the first and last passive trip points.
- *
- * If there is only one trip point, then that's considered to be the
- * "maximum desired temperature" trip point and the governor is always
- * on. If there are no passive or active trip points, then the
- * governor won't do anything. In fact, its throttle function
- * won't be called at all.
- */
-static void get_governor_trips(struct thermal_zone_device *tz,
- struct power_allocator_params *params)
-{
- int i, last_active, last_passive;
- bool found_first_passive;
-
- found_first_passive = false;
- last_active = INVALID_TRIP;
- last_passive = INVALID_TRIP;
-
- for (i = 0; i < tz->trips; i++) {
- enum thermal_trip_type type;
- int ret;
-
- ret = tz->ops->get_trip_type(tz, i, &type);
- if (ret) {
- dev_warn(&tz->device,
- "Failed to get trip point %d type: %d\n", i,
- ret);
- continue;
- }
-
- if (type == THERMAL_TRIP_PASSIVE) {
- if (!found_first_passive) {
- params->trip_switch_on = i;
- found_first_passive = true;
- } else {
- last_passive = i;
- }
- } else if (type == THERMAL_TRIP_ACTIVE) {
- last_active = i;
- } else {
- break;
- }
- }
-
- if (last_passive != INVALID_TRIP) {
- params->trip_max_desired_temperature = last_passive;
- } else if (found_first_passive) {
- params->trip_max_desired_temperature = params->trip_switch_on;
- params->trip_switch_on = INVALID_TRIP;
- } else {
- params->trip_switch_on = INVALID_TRIP;
- params->trip_max_desired_temperature = last_active;
- }
-}
-
-static void reset_pid_controller(struct power_allocator_params *params)
-{
- params->err_integral = 0;
- params->prev_err = 0;
-}
-
-static void allow_maximum_power(struct thermal_zone_device *tz)
-{
- struct thermal_instance *instance;
- struct power_allocator_params *params = tz->governor_data;
-
- mutex_lock(&tz->lock);
- list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
- if ((instance->trip != params->trip_max_desired_temperature) ||
- (!cdev_is_power_actor(instance->cdev)))
- continue;
-
- instance->target = 0;
- mutex_lock(&instance->cdev->lock);
- instance->cdev->updated = false;
- mutex_unlock(&instance->cdev->lock);
- thermal_cdev_update(instance->cdev);
- }
- mutex_unlock(&tz->lock);
-}
-
-/**
- * power_allocator_bind() - bind the power_allocator governor to a thermal zone
- * @tz: thermal zone to bind it to
- *
- * Initialize the PID controller parameters and bind it to the thermal
- * zone.
- *
- * Return: 0 on success, or -ENOMEM if we ran out of memory.
- */
-static int power_allocator_bind(struct thermal_zone_device *tz)
-{
- int ret;
- struct power_allocator_params *params;
- int control_temp;
-
- params = kzalloc(sizeof(*params), GFP_KERNEL);
- if (!params)
- return -ENOMEM;
-
- if (!tz->tzp) {
- tz->tzp = kzalloc(sizeof(*tz->tzp), GFP_KERNEL);
- if (!tz->tzp) {
- ret = -ENOMEM;
- goto free_params;
- }
-
- params->allocated_tzp = true;
- }
-
- if (!tz->tzp->sustainable_power)
- dev_warn(&tz->device, "power_allocator: sustainable_power will be estimated\n");
-
- get_governor_trips(tz, params);
-
- if (tz->trips > 0) {
- ret = tz->ops->get_trip_temp(tz,
- params->trip_max_desired_temperature,
- &control_temp);
- if (!ret)
- estimate_pid_constants(tz, tz->tzp->sustainable_power,
- params->trip_switch_on,
- control_temp, false);
- }
-
- reset_pid_controller(params);
-
- tz->governor_data = params;
-
- return 0;
-
-free_params:
- kfree(params);
-
- return ret;
-}
-
-static void power_allocator_unbind(struct thermal_zone_device *tz)
-{
- struct power_allocator_params *params = tz->governor_data;
-
- dev_dbg(&tz->device, "Unbinding from thermal zone %d\n", tz->id);
-
- if (params->allocated_tzp) {
- kfree(tz->tzp);
- tz->tzp = NULL;
- }
-
- kfree(tz->governor_data);
- tz->governor_data = NULL;
-}
-
-static int power_allocator_throttle(struct thermal_zone_device *tz, int trip)
-{
- int ret;
- int switch_on_temp, control_temp;
- struct power_allocator_params *params = tz->governor_data;
-
- /*
- * We get called for every trip point but we only need to do
- * our calculations once
- */
- if (trip != params->trip_max_desired_temperature)
- return 0;
-
- ret = tz->ops->get_trip_temp(tz, params->trip_switch_on,
- &switch_on_temp);
- if (!ret && (tz->temperature < switch_on_temp)) {
- tz->passive = 0;
- reset_pid_controller(params);
- allow_maximum_power(tz);
- return 0;
- }
-
- tz->passive = 1;
-
- ret = tz->ops->get_trip_temp(tz, params->trip_max_desired_temperature,
- &control_temp);
- if (ret) {
- dev_warn(&tz->device,
- "Failed to get the maximum desired temperature: %d\n",
- ret);
- return ret;
- }
-
- return allocate_power(tz, control_temp);
-}
-
-static struct thermal_governor thermal_gov_power_allocator = {
- .name = "power_allocator",
- .bind_to_tz = power_allocator_bind,
- .unbind_from_tz = power_allocator_unbind,
- .throttle = power_allocator_throttle,
-};
-THERMAL_GOVERNOR_DECLARE(thermal_gov_power_allocator);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * step_wise.c - A step-by-step Thermal throttling governor
- *
- * Copyright (C) 2012 Intel Corp
- * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- */
-
-#include <linux/thermal.h>
-#include <trace/events/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, do nothing
- * 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,
- * deactivate the thermal instance
- */
-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;
- unsigned long next_target;
-
- /*
- * We keep this instance the way it is by default.
- * Otherwise, we use the current state of the
- * cdev in use to determine the next_target.
- */
- cdev->ops->get_cur_state(cdev, &cur_state);
- next_target = instance->target;
- dev_dbg(&cdev->device, "cur_state=%ld\n", cur_state);
-
- if (!instance->initialized) {
- if (throttle) {
- next_target = (cur_state + 1) >= instance->upper ?
- instance->upper :
- ((cur_state + 1) < instance->lower ?
- instance->lower : (cur_state + 1));
- } else {
- next_target = THERMAL_NO_TARGET;
- }
-
- return next_target;
- }
-
- switch (trend) {
- case THERMAL_TREND_RAISING:
- if (throttle) {
- next_target = cur_state < instance->upper ?
- (cur_state + 1) : instance->upper;
- if (next_target < instance->lower)
- next_target = instance->lower;
- }
- break;
- case THERMAL_TREND_RAISE_FULL:
- if (throttle)
- next_target = instance->upper;
- break;
- case THERMAL_TREND_DROPPING:
- if (cur_state <= instance->lower) {
- if (!throttle)
- next_target = THERMAL_NO_TARGET;
- } else {
- if (!throttle) {
- next_target = cur_state - 1;
- if (next_target > instance->upper)
- next_target = instance->upper;
- }
- }
- break;
- case THERMAL_TREND_DROP_FULL:
- if (cur_state == instance->lower) {
- if (!throttle)
- next_target = THERMAL_NO_TARGET;
- } else
- next_target = instance->lower;
- break;
- default:
- break;
- }
-
- return next_target;
-}
-
-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)
-{
- int 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;
- trace_thermal_zone_trip(tz, trip, trip_type);
- }
-
- dev_dbg(&tz->device, "Trip%d[type=%d,temp=%d]: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);
-
- if (instance->initialized && old_target == instance->target)
- continue;
-
- /* 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->initialized = true;
- mutex_lock(&instance->cdev->lock);
- instance->cdev->updated = false; /* cdev needs update */
- mutex_unlock(&instance->cdev->lock);
- }
-
- mutex_unlock(&tz->lock);
-}
-
-/**
- * step_wise_throttle - throttles devices associated with the given zone
- * @tz: thermal_zone_device
- * @trip: trip point index
- *
- * 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,
-};
-THERMAL_GOVERNOR_DECLARE(thermal_gov_step_wise);
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * user_space.c - A simple user space Thermal events notifier
- *
- * Copyright (C) 2012 Intel Corp
- * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- */
-
-#include <linux/slab.h>
-#include <linux/thermal.h>
-
-#include "thermal_core.h"
-
-/**
- * notify_user_space - Notifies user space about thermal events
- * @tz: thermal_zone_device
- * @trip: trip point index
- *
- * This function notifies the user space through UEvents.
- */
-static int notify_user_space(struct thermal_zone_device *tz, int trip)
-{
- char *thermal_prop[5];
- int i;
-
- mutex_lock(&tz->lock);
- thermal_prop[0] = kasprintf(GFP_KERNEL, "NAME=%s", tz->type);
- thermal_prop[1] = kasprintf(GFP_KERNEL, "TEMP=%d", tz->temperature);
- thermal_prop[2] = kasprintf(GFP_KERNEL, "TRIP=%d", trip);
- thermal_prop[3] = kasprintf(GFP_KERNEL, "EVENT=%d", tz->notify_event);
- thermal_prop[4] = NULL;
- kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, thermal_prop);
- for (i = 0; i < 4; ++i)
- kfree(thermal_prop[i]);
- mutex_unlock(&tz->lock);
- return 0;
-}
-
-static struct thermal_governor thermal_gov_user_space = {
- .name = "user_space",
- .throttle = notify_user_space,
-};
-THERMAL_GOVERNOR_DECLARE(thermal_gov_user_space);
projects / linux-2.6-microblaze.git / commitdiff