thermal: gov_power_allocator: Use trip pointers instead of trip indices

Modify the power allocator thermal governor to use trip pointers instead
of trip indices everywhere except for the power_allocator_throttle()
second argument that will be changed subsequently along with the
definition of the .throttle() governor callback.

The general functionality is not expected to be changed.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>

diff --git a/drivers/thermal/gov_power_allocator.c b/drivers/thermal/gov_power_allocator.c
index 1faf55446ba239a3c9377842c0d8e94c04c0c73e..c0d29d2863745eac9234710535ea2126fd56ca5b 100644 (file)
--- a/drivers/thermal/gov_power_allocator.c
+++ b/drivers/thermal/gov_power_allocator.c
@@ -16,8 +16,6 @@
 
 #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)
@@ -55,23 +53,23 @@ static inline s64 div_frac(s64 x, s64 y)
  * @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.
+ * @sustainable_power: Sustainable power (heat) that this thermal zone can
+ *                     dissipate
  * @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_switch_on should be NULL.
  * @trip_max_desired_temperature:      last passive trip point of the thermal
  *                                     zone.  The temperature we are
  *                                     controlling for.
- * @sustainable_power: Sustainable power (heat) that this thermal zone can
- *                     dissipate
  */
 struct power_allocator_params {
        bool allocated_tzp;
        s64 err_integral;
        s32 prev_err;
-       int trip_switch_on;
-       int trip_max_desired_temperature;
        u32 sustainable_power;
+       const struct thermal_trip *trip_switch_on;
+       const struct thermal_trip *trip_max_desired_temperature;
 };
 
 /**
@@ -90,14 +88,12 @@ 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;
-       const struct thermal_trip *trip_max_desired_temperature =
-                       &tz->trips[params->trip_max_desired_temperature];
 
        list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
                struct thermal_cooling_device *cdev = instance->cdev;
                u32 min_power;
 
-               if (instance->trip != trip_max_desired_temperature)
+               if (instance->trip != params->trip_max_desired_temperature)
                        continue;
 
                if (!cdev_is_power_actor(cdev))
@@ -116,24 +112,22 @@ static u32 estimate_sustainable_power(struct thermal_zone_device *tz)
  * 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
+ * @trip_switch_on:    trip point for the switch on temperature
  * @control_temp:      target temperature for the power allocator governor
  *
  * This function is used to update the estimation of the PID
  * controller constants in struct thermal_zone_parameters.
  */
 static void estimate_pid_constants(struct thermal_zone_device *tz,
-                                  u32 sustainable_power, int trip_switch_on,
+                                  u32 sustainable_power,
+                                  const struct thermal_trip *trip_switch_on,
                                   int control_temp)
 {
-       struct thermal_trip trip;
        u32 temperature_threshold = control_temp;
-       int ret;
        s32 k_i;
 
-       ret = __thermal_zone_get_trip(tz, trip_switch_on, &trip);
-       if (!ret)
-               temperature_threshold -= trip.temperature;
+       if (trip_switch_on)
+               temperature_threshold -= trip_switch_on->temperature;
 
        /*
         * estimate_pid_constants() tries to find appropriate default
@@ -386,7 +380,7 @@ static int allocate_power(struct thermal_zone_device *tz,
        struct thermal_instance *instance;
        struct power_allocator_params *params = tz->governor_data;
        const struct thermal_trip *trip_max_desired_temperature =
-                       &tz->trips[params->trip_max_desired_temperature];
+                                       params->trip_max_desired_temperature;
        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;
@@ -496,7 +490,7 @@ static int allocate_power(struct thermal_zone_device *tz,
 }
 
 /**
- * get_governor_trips() - get the number of the two trip points that are key for this governor
+ * get_governor_trips() - get the two trip points that are key for this governor
  * @tz:        thermal zone to operate on
  * @params:    pointer to private data for this governor
  *
@@ -513,46 +507,36 @@ static int allocate_power(struct thermal_zone_device *tz,
 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->num_trips; i++) {
-               struct thermal_trip trip;
-               int ret;
-
-               ret = __thermal_zone_get_trip(tz, i, &trip);
-               if (ret) {
-                       dev_warn(&tz->device,
-                                "Failed to get trip point %d type: %d\n", i,
-                                ret);
-                       continue;
-               }
-
-               if (trip.type == THERMAL_TRIP_PASSIVE) {
-                       if (!found_first_passive) {
-                               params->trip_switch_on = i;
-                               found_first_passive = true;
-                       } else  {
-                               last_passive = i;
+       const struct thermal_trip *first_passive = NULL;
+       const struct thermal_trip *last_passive = NULL;
+       const struct thermal_trip *last_active = NULL;
+       const struct thermal_trip *trip;
+
+       for_each_trip(tz, trip) {
+               switch (trip->type) {
+               case THERMAL_TRIP_PASSIVE:
+                       if (!first_passive) {
+                               first_passive = trip;
+                               break;
                        }
-               } else if (trip.type == THERMAL_TRIP_ACTIVE) {
-                       last_active = i;
-               } else {
+                       last_passive = trip;
+                       break;
+               case THERMAL_TRIP_ACTIVE:
+                       last_active = trip;
+                       break;
+               default:
                        break;
                }
        }
 
-       if (last_passive != INVALID_TRIP) {
+       if (last_passive) {
+               params->trip_switch_on = first_passive;
                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 if (first_passive) {
+               params->trip_switch_on = NULL;
+               params->trip_max_desired_temperature = first_passive;
        } else {
-               params->trip_switch_on = INVALID_TRIP;
+               params->trip_switch_on = NULL;
                params->trip_max_desired_temperature = last_active;
        }
 }
@@ -567,14 +551,12 @@ static void allow_maximum_power(struct thermal_zone_device *tz, bool update)
 {
        struct thermal_instance *instance;
        struct power_allocator_params *params = tz->governor_data;
-       const struct thermal_trip *trip_max_desired_temperature =
-                       &tz->trips[params->trip_max_desired_temperature];
        u32 req_power;
 
        list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
                struct thermal_cooling_device *cdev = instance->cdev;
 
-               if ((instance->trip != trip_max_desired_temperature) ||
+               if (instance->trip != params->trip_max_desired_temperature ||
                    (!cdev_is_power_actor(instance->cdev)))
                        continue;
 
@@ -636,7 +618,6 @@ static int power_allocator_bind(struct thermal_zone_device *tz)
 {
        int ret;
        struct power_allocator_params *params;
-       struct thermal_trip trip;
 
        ret = check_power_actors(tz);
        if (ret)
@@ -661,13 +642,11 @@ static int power_allocator_bind(struct thermal_zone_device *tz)
 
        get_governor_trips(tz, params);
 
-       if (tz->num_trips > 0) {
-               ret = __thermal_zone_get_trip(tz, params->trip_max_desired_temperature,
-                                             &trip);
-               if (!ret)
-                       estimate_pid_constants(tz, tz->tzp->sustainable_power,
-                                              params->trip_switch_on,
-                                              trip.temperature);
+       if (params->trip_max_desired_temperature) {
+               int temp = params->trip_max_desired_temperature->temperature;
+
+               estimate_pid_constants(tz, tz->tzp->sustainable_power,
+                                      params->trip_switch_on, temp);
        }
 
        reset_pid_controller(params);
@@ -697,11 +676,10 @@ static void power_allocator_unbind(struct thermal_zone_device *tz)
        tz->governor_data = NULL;
 }
 
-static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_id)
+static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_index)
 {
        struct power_allocator_params *params = tz->governor_data;
-       struct thermal_trip trip;
-       int ret;
+       const struct thermal_trip *trip = &tz->trips[trip_index];
        bool update;
 
        lockdep_assert_held(&tz->lock);
@@ -710,12 +688,12 @@ static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_id)
         * We get called for every trip point but we only need to do
         * our calculations once
         */
-       if (trip_id != params->trip_max_desired_temperature)
+       if (trip != params->trip_max_desired_temperature)
                return 0;
 
-       ret = __thermal_zone_get_trip(tz, params->trip_switch_on, &trip);
-       if (!ret && (tz->temperature < trip.temperature)) {
-               update = (tz->last_temperature >= trip.temperature);
+       trip = params->trip_switch_on;
+       if (trip && tz->temperature < trip->temperature) {
+               update = tz->last_temperature >= trip->temperature;
                tz->passive = 0;
                reset_pid_controller(params);
                allow_maximum_power(tz, update);
@@ -724,14 +702,7 @@ static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_id)
 
        tz->passive = 1;
 
-       ret = __thermal_zone_get_trip(tz, params->trip_max_desired_temperature, &trip);
-       if (ret) {
-               dev_warn(&tz->device, "Failed to get the maximum desired temperature: %d\n",
-                        ret);
-               return ret;
-       }
-
-       return allocate_power(tz, trip.temperature);
+       return allocate_power(tz, params->trip_max_desired_temperature->temperature);
 }
 
 static struct thermal_governor thermal_gov_power_allocator = {