tt.c

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/******************************************************************************
 *
 * Copyright(c) 2007 - 2012 Intel Corporation. All rights reserved.
 *
 * Portions of this file are derived from the ipw3945 project, as well
 * as portions of the ieee80211 subsystem header files.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
 *
 * The full GNU General Public License is included in this distribution in the
 * file called LICENSE.
 *
 * Contact Information:
 *  Intel Linux Wireless <[email protected]>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *****************************************************************************/


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <net/mac80211.h>
#include "iwl-io.h"
#include "iwl-modparams.h"
#include "iwl-debug.h"
#include "agn.h"
#include "dev.h"
#include "commands.h"
#include "tt.h"

/* default Thermal Throttling transaction table
 * Current state   |         Throttling Down               |  Throttling Up
 *=============================================================================
 *                 Condition Nxt State  Condition Nxt State Condition Nxt State
 *-----------------------------------------------------------------------------
 *     IWL_TI_0     T >= 114   CT_KILL  114>T>=105   TI_1      N/A      N/A
 *     IWL_TI_1     T >= 114   CT_KILL  114>T>=110   TI_2     T<=95     TI_0
 *     IWL_TI_2     T >= 114   CT_KILL                        T<=100    TI_1
 *    IWL_CT_KILL      N/A       N/A       N/A        N/A     T<=95     TI_0
 *=============================================================================
 */
static const struct iwl_tt_trans tt_range_0[IWL_TI_STATE_MAX - 1] = {
    {IWL_TI_0, IWL_ABSOLUTE_ZERO, 104},
    {IWL_TI_1, 105, CT_KILL_THRESHOLD - 1},
    {IWL_TI_CT_KILL, CT_KILL_THRESHOLD, IWL_ABSOLUTE_MAX}
};
static const struct iwl_tt_trans tt_range_1[IWL_TI_STATE_MAX - 1] = {
    {IWL_TI_0, IWL_ABSOLUTE_ZERO, 95},
    {IWL_TI_2, 110, CT_KILL_THRESHOLD - 1},
    {IWL_TI_CT_KILL, CT_KILL_THRESHOLD, IWL_ABSOLUTE_MAX}
};
static const struct iwl_tt_trans tt_range_2[IWL_TI_STATE_MAX - 1] = {
    {IWL_TI_1, IWL_ABSOLUTE_ZERO, 100},
    {IWL_TI_CT_KILL, CT_KILL_THRESHOLD, IWL_ABSOLUTE_MAX},
    {IWL_TI_CT_KILL, CT_KILL_THRESHOLD, IWL_ABSOLUTE_MAX}
};
static const struct iwl_tt_trans tt_range_3[IWL_TI_STATE_MAX - 1] = {
    {IWL_TI_0, IWL_ABSOLUTE_ZERO, CT_KILL_EXIT_THRESHOLD},
    {IWL_TI_CT_KILL, CT_KILL_EXIT_THRESHOLD + 1, IWL_ABSOLUTE_MAX},
    {IWL_TI_CT_KILL, CT_KILL_EXIT_THRESHOLD + 1, IWL_ABSOLUTE_MAX}
};

/* Advance Thermal Throttling default restriction table */
static const struct iwl_tt_restriction restriction_range[IWL_TI_STATE_MAX] = {
    {IWL_ANT_OK_MULTI, IWL_ANT_OK_MULTI, true },
    {IWL_ANT_OK_SINGLE, IWL_ANT_OK_MULTI, true },
    {IWL_ANT_OK_SINGLE, IWL_ANT_OK_SINGLE, false },
    {IWL_ANT_OK_NONE, IWL_ANT_OK_NONE, false }
};

bool iwl_tt_is_low_power_state(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    if (tt->state >= IWL_TI_1)
        return true;
    return false;
}

u8 iwl_tt_current_power_mode(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    return tt->tt_power_mode;
}

bool iwl_ht_enabled(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    struct iwl_tt_restriction *restriction;

    if (!priv->thermal_throttle.advanced_tt)
        return true;
    restriction = tt->restriction + tt->state;
    return restriction->is_ht;
}

static bool iwl_within_ct_kill_margin(struct iwl_priv *priv)
{
    s32 temp = priv->temperature; /* degrees CELSIUS except specified */
    bool within_margin = false;

    if (!priv->thermal_throttle.advanced_tt)
        within_margin = ((temp + IWL_TT_CT_KILL_MARGIN) >=
                CT_KILL_THRESHOLD_LEGACY) ? true : false;
    else
        within_margin = ((temp + IWL_TT_CT_KILL_MARGIN) >=
                CT_KILL_THRESHOLD) ? true : false;
    return within_margin;
}

bool iwl_check_for_ct_kill(struct iwl_priv *priv)
{
    bool is_ct_kill = false;

    if (iwl_within_ct_kill_margin(priv)) {
        iwl_tt_enter_ct_kill(priv);
        is_ct_kill = true;
    }
    return is_ct_kill;
}

enum iwl_antenna_ok iwl_tx_ant_restriction(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    struct iwl_tt_restriction *restriction;

    if (!priv->thermal_throttle.advanced_tt)
        return IWL_ANT_OK_MULTI;
    restriction = tt->restriction + tt->state;
    return restriction->tx_stream;
}

enum iwl_antenna_ok iwl_rx_ant_restriction(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    struct iwl_tt_restriction *restriction;

    if (!priv->thermal_throttle.advanced_tt)
        return IWL_ANT_OK_MULTI;
    restriction = tt->restriction + tt->state;
    return restriction->rx_stream;
}

#define CT_KILL_EXIT_DURATION (5)   /* 5 seconds duration */
#define CT_KILL_WAITING_DURATION (300)  /* 300ms duration */

/*
 * toggle the bit to wake up uCode and check the temperature
 * if the temperature is below CT, uCode will stay awake and send card
 * state notification with CT_KILL bit clear to inform Thermal Throttling
 * Management to change state. Otherwise, uCode will go back to sleep
 * without doing anything, driver should continue the 5 seconds timer
 * to wake up uCode for temperature check until temperature drop below CT
 */
static void iwl_tt_check_exit_ct_kill(unsigned long data)
{
    struct iwl_priv *priv = (struct iwl_priv *)data;
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    unsigned long flags;

    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    if (tt->state == IWL_TI_CT_KILL) {
        if (priv->thermal_throttle.ct_kill_toggle) {
            iwl_write32(priv->trans, CSR_UCODE_DRV_GP1_CLR,
                    CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
            priv->thermal_throttle.ct_kill_toggle = false;
        } else {
            iwl_write32(priv->trans, CSR_UCODE_DRV_GP1_SET,
                    CSR_UCODE_DRV_GP1_REG_BIT_CT_KILL_EXIT);
            priv->thermal_throttle.ct_kill_toggle = true;
        }
        iwl_read32(priv->trans, CSR_UCODE_DRV_GP1);
        spin_lock_irqsave(&priv->trans->reg_lock, flags);
        if (likely(iwl_grab_nic_access(priv->trans)))
            iwl_release_nic_access(priv->trans);
        spin_unlock_irqrestore(&priv->trans->reg_lock, flags);

        /* Reschedule the ct_kill timer to occur in
         * CT_KILL_EXIT_DURATION seconds to ensure we get a
         * thermal update */
        IWL_DEBUG_TEMP(priv, "schedule ct_kill exit timer\n");
        mod_timer(&priv->thermal_throttle.ct_kill_exit_tm,
              jiffies + CT_KILL_EXIT_DURATION * HZ);
    }
}

static void iwl_perform_ct_kill_task(struct iwl_priv *priv,
               bool stop)
{
    if (stop) {
        IWL_DEBUG_TEMP(priv, "Stop all queues\n");
        if (priv->mac80211_registered)
            ieee80211_stop_queues(priv->hw);
        IWL_DEBUG_TEMP(priv,
                "Schedule 5 seconds CT_KILL Timer\n");
        mod_timer(&priv->thermal_throttle.ct_kill_exit_tm,
              jiffies + CT_KILL_EXIT_DURATION * HZ);
    } else {
        IWL_DEBUG_TEMP(priv, "Wake all queues\n");
        if (priv->mac80211_registered)
            ieee80211_wake_queues(priv->hw);
    }
}

static void iwl_tt_ready_for_ct_kill(unsigned long data)
{
    struct iwl_priv *priv = (struct iwl_priv *)data;
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    /* temperature timer expired, ready to go into CT_KILL state */
    if (tt->state != IWL_TI_CT_KILL) {
        IWL_DEBUG_TEMP(priv, "entering CT_KILL state when "
                "temperature timer expired\n");
        tt->state = IWL_TI_CT_KILL;
        set_bit(STATUS_CT_KILL, &priv->status);
        iwl_perform_ct_kill_task(priv, true);
    }
}

static void iwl_prepare_ct_kill_task(struct iwl_priv *priv)
{
    IWL_DEBUG_TEMP(priv, "Prepare to enter IWL_TI_CT_KILL\n");
    /* make request to retrieve statistics information */
    iwl_send_statistics_request(priv, CMD_SYNC, false);
    /* Reschedule the ct_kill wait timer */
    mod_timer(&priv->thermal_throttle.ct_kill_waiting_tm,
         jiffies + msecs_to_jiffies(CT_KILL_WAITING_DURATION));
}

#define IWL_MINIMAL_POWER_THRESHOLD     (CT_KILL_THRESHOLD_LEGACY)
#define IWL_REDUCED_PERFORMANCE_THRESHOLD_2 (100)
#define IWL_REDUCED_PERFORMANCE_THRESHOLD_1 (90)

/*
 * Legacy thermal throttling
 * 1) Avoid NIC destruction due to high temperatures
 *  Chip will identify dangerously high temperatures that can
 *  harm the device and will power down
 * 2) Avoid the NIC power down due to high temperature
 *  Throttle early enough to lower the power consumption before
 *  drastic steps are needed
 */
static void iwl_legacy_tt_handler(struct iwl_priv *priv, s32 temp, bool force)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    enum iwl_tt_state old_state;

#ifdef CONFIG_IWLWIFI_DEBUG
    if ((tt->tt_previous_temp) &&
        (temp > tt->tt_previous_temp) &&
        ((temp - tt->tt_previous_temp) >
        IWL_TT_INCREASE_MARGIN)) {
        IWL_DEBUG_TEMP(priv,
            "Temperature increase %d degree Celsius\n",
            (temp - tt->tt_previous_temp));
    }
#endif
    old_state = tt->state;
    /* in Celsius */
    if (temp >= IWL_MINIMAL_POWER_THRESHOLD)
        tt->state = IWL_TI_CT_KILL;
    else if (temp >= IWL_REDUCED_PERFORMANCE_THRESHOLD_2)
        tt->state = IWL_TI_2;
    else if (temp >= IWL_REDUCED_PERFORMANCE_THRESHOLD_1)
        tt->state = IWL_TI_1;
    else
        tt->state = IWL_TI_0;

#ifdef CONFIG_IWLWIFI_DEBUG
    tt->tt_previous_temp = temp;
#endif
    /* stop ct_kill_waiting_tm timer */
    del_timer_sync(&priv->thermal_throttle.ct_kill_waiting_tm);
    if (tt->state != old_state) {
        switch (tt->state) {
        case IWL_TI_0:
            /*
             * When the system is ready to go back to IWL_TI_0
             * we only have to call iwl_power_update_mode() to
             * do so.
             */
            break;
        case IWL_TI_1:
            tt->tt_power_mode = IWL_POWER_INDEX_3;
            break;
        case IWL_TI_2:
            tt->tt_power_mode = IWL_POWER_INDEX_4;
            break;
        default:
            tt->tt_power_mode = IWL_POWER_INDEX_5;
            break;
        }
        mutex_lock(&priv->mutex);
        if (old_state == IWL_TI_CT_KILL)
            clear_bit(STATUS_CT_KILL, &priv->status);
        if (tt->state != IWL_TI_CT_KILL &&
            iwl_power_update_mode(priv, true)) {
            /* TT state not updated
             * try again during next temperature read
             */
            if (old_state == IWL_TI_CT_KILL)
                set_bit(STATUS_CT_KILL, &priv->status);
            tt->state = old_state;
            IWL_ERR(priv, "Cannot update power mode, "
                    "TT state not updated\n");
        } else {
            if (tt->state == IWL_TI_CT_KILL) {
                if (force) {
                    set_bit(STATUS_CT_KILL, &priv->status);
                    iwl_perform_ct_kill_task(priv, true);
                } else {
                    iwl_prepare_ct_kill_task(priv);
                    tt->state = old_state;
                }
            } else if (old_state == IWL_TI_CT_KILL &&
                 tt->state != IWL_TI_CT_KILL)
                iwl_perform_ct_kill_task(priv, false);
            IWL_DEBUG_TEMP(priv, "Temperature state changed %u\n",
                    tt->state);
            IWL_DEBUG_TEMP(priv, "Power Index change to %u\n",
                    tt->tt_power_mode);
        }
        mutex_unlock(&priv->mutex);
    }
}

/*
 * Advance thermal throttling
 * 1) Avoid NIC destruction due to high temperatures
 *  Chip will identify dangerously high temperatures that can
 *  harm the device and will power down
 * 2) Avoid the NIC power down due to high temperature
 *  Throttle early enough to lower the power consumption before
 *  drastic steps are needed
 *  Actions include relaxing the power down sleep thresholds and
 *  decreasing the number of TX streams
 * 3) Avoid throughput performance impact as much as possible
 *
 *=============================================================================
 *                 Condition Nxt State  Condition Nxt State Condition Nxt State
 *-----------------------------------------------------------------------------
 *     IWL_TI_0     T >= 114   CT_KILL  114>T>=105   TI_1      N/A      N/A
 *     IWL_TI_1     T >= 114   CT_KILL  114>T>=110   TI_2     T<=95     TI_0
 *     IWL_TI_2     T >= 114   CT_KILL                        T<=100    TI_1
 *    IWL_CT_KILL      N/A       N/A       N/A        N/A     T<=95     TI_0
 *=============================================================================
 */
static void iwl_advance_tt_handler(struct iwl_priv *priv, s32 temp, bool force)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    int i;
    bool changed = false;
    enum iwl_tt_state old_state;
    struct iwl_tt_trans *transaction;

    old_state = tt->state;
    for (i = 0; i < IWL_TI_STATE_MAX - 1; i++) {
        /* based on the current TT state,
         * find the curresponding transaction table
         * each table has (IWL_TI_STATE_MAX - 1) entries
         * tt->transaction + ((old_state * (IWL_TI_STATE_MAX - 1))
         * will advance to the correct table.
         * then based on the current temperature
         * find the next state need to transaction to
         * go through all the possible (IWL_TI_STATE_MAX - 1) entries
         * in the current table to see if transaction is needed
         */
        transaction = tt->transaction +
            ((old_state * (IWL_TI_STATE_MAX - 1)) + i);
        if (temp >= transaction->tt_low &&
            temp <= transaction->tt_high) {
#ifdef CONFIG_IWLWIFI_DEBUG
            if ((tt->tt_previous_temp) &&
                (temp > tt->tt_previous_temp) &&
                ((temp - tt->tt_previous_temp) >
                IWL_TT_INCREASE_MARGIN)) {
                IWL_DEBUG_TEMP(priv,
                    "Temperature increase %d "
                    "degree Celsius\n",
                    (temp - tt->tt_previous_temp));
            }
            tt->tt_previous_temp = temp;
#endif
            if (old_state !=
                transaction->next_state) {
                changed = true;
                tt->state =
                    transaction->next_state;
            }
            break;
        }
    }
    /* stop ct_kill_waiting_tm timer */
    del_timer_sync(&priv->thermal_throttle.ct_kill_waiting_tm);
    if (changed) {
        if (tt->state >= IWL_TI_1) {
            /* force PI = IWL_POWER_INDEX_5 in the case of TI > 0 */
            tt->tt_power_mode = IWL_POWER_INDEX_5;

            if (!iwl_ht_enabled(priv)) {
                struct iwl_rxon_context *ctx;

                for_each_context(priv, ctx) {
                    struct iwl_rxon_cmd *rxon;

                    rxon = &ctx->staging;

                    /* disable HT */
                    rxon->flags &= ~(
                        RXON_FLG_CHANNEL_MODE_MSK |
                        RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK |
                        RXON_FLG_HT40_PROT_MSK |
                        RXON_FLG_HT_PROT_MSK);
                }
            } else {
                /* check HT capability and set
                 * according to the system HT capability
                 * in case get disabled before */
                iwl_set_rxon_ht(priv, &priv->current_ht_config);
            }

        } else {
            /*
             * restore system power setting -- it will be
             * recalculated automatically.
             */

            /* check HT capability and set
             * according to the system HT capability
             * in case get disabled before */
            iwl_set_rxon_ht(priv, &priv->current_ht_config);
        }
        mutex_lock(&priv->mutex);
        if (old_state == IWL_TI_CT_KILL)
            clear_bit(STATUS_CT_KILL, &priv->status);
        if (tt->state != IWL_TI_CT_KILL &&
            iwl_power_update_mode(priv, true)) {
            /* TT state not updated
             * try again during next temperature read
             */
            IWL_ERR(priv, "Cannot update power mode, "
                    "TT state not updated\n");
            if (old_state == IWL_TI_CT_KILL)
                set_bit(STATUS_CT_KILL, &priv->status);
            tt->state = old_state;
        } else {
            IWL_DEBUG_TEMP(priv,
                    "Thermal Throttling to new state: %u\n",
                    tt->state);
            if (old_state != IWL_TI_CT_KILL &&
                tt->state == IWL_TI_CT_KILL) {
                if (force) {
                    IWL_DEBUG_TEMP(priv,
                        "Enter IWL_TI_CT_KILL\n");
                    set_bit(STATUS_CT_KILL, &priv->status);
                    iwl_perform_ct_kill_task(priv, true);
                } else {
                    iwl_prepare_ct_kill_task(priv);
                    tt->state = old_state;
                }
            } else if (old_state == IWL_TI_CT_KILL &&
                  tt->state != IWL_TI_CT_KILL) {
                IWL_DEBUG_TEMP(priv, "Exit IWL_TI_CT_KILL\n");
                iwl_perform_ct_kill_task(priv, false);
            }
        }
        mutex_unlock(&priv->mutex);
    }
}

/* Card State Notification indicated reach critical temperature
 * if PSP not enable, no Thermal Throttling function will be performed
 * just set the GP1 bit to acknowledge the event
 * otherwise, go into IWL_TI_CT_KILL state
 * since Card State Notification will not provide any temperature reading
 * for Legacy mode
 * so just pass the CT_KILL temperature to iwl_legacy_tt_handler()
 * for advance mode
 * pass CT_KILL_THRESHOLD+1 to make sure move into IWL_TI_CT_KILL state
 */
static void iwl_bg_ct_enter(struct work_struct *work)
{
    struct iwl_priv *priv = container_of(work, struct iwl_priv, ct_enter);
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    if (!iwl_is_ready(priv))
        return;

    if (tt->state != IWL_TI_CT_KILL) {
        IWL_ERR(priv, "Device reached critical temperature "
                  "- ucode going to sleep!\n");
        if (!priv->thermal_throttle.advanced_tt)
            iwl_legacy_tt_handler(priv,
                          IWL_MINIMAL_POWER_THRESHOLD,
                          true);
        else
            iwl_advance_tt_handler(priv,
                           CT_KILL_THRESHOLD + 1, true);
    }
}

/* Card State Notification indicated out of critical temperature
 * since Card State Notification will not provide any temperature reading
 * so pass the IWL_REDUCED_PERFORMANCE_THRESHOLD_2 temperature
 * to iwl_legacy_tt_handler() to get out of IWL_CT_KILL state
 */
static void iwl_bg_ct_exit(struct work_struct *work)
{
    struct iwl_priv *priv = container_of(work, struct iwl_priv, ct_exit);
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    if (!iwl_is_ready(priv))
        return;

    /* stop ct_kill_exit_tm timer */
    del_timer_sync(&priv->thermal_throttle.ct_kill_exit_tm);

    if (tt->state == IWL_TI_CT_KILL) {
        IWL_ERR(priv,
            "Device temperature below critical"
            "- ucode awake!\n");
        /*
         * exit from CT_KILL state
         * reset the current temperature reading
         */
        priv->temperature = 0;
        if (!priv->thermal_throttle.advanced_tt)
            iwl_legacy_tt_handler(priv,
                      IWL_REDUCED_PERFORMANCE_THRESHOLD_2,
                      true);
        else
            iwl_advance_tt_handler(priv, CT_KILL_EXIT_THRESHOLD,
                           true);
    }
}

void iwl_tt_enter_ct_kill(struct iwl_priv *priv)
{
    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    IWL_DEBUG_TEMP(priv, "Queueing critical temperature enter.\n");
    queue_work(priv->workqueue, &priv->ct_enter);
}

void iwl_tt_exit_ct_kill(struct iwl_priv *priv)
{
    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    IWL_DEBUG_TEMP(priv, "Queueing critical temperature exit.\n");
    queue_work(priv->workqueue, &priv->ct_exit);
}

static void iwl_bg_tt_work(struct work_struct *work)
{
    struct iwl_priv *priv = container_of(work, struct iwl_priv, tt_work);
    s32 temp = priv->temperature; /* degrees CELSIUS except specified */

    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    if (!priv->thermal_throttle.advanced_tt)
        iwl_legacy_tt_handler(priv, temp, false);
    else
        iwl_advance_tt_handler(priv, temp, false);
}

void iwl_tt_handler(struct iwl_priv *priv)
{
    if (test_bit(STATUS_EXIT_PENDING, &priv->status))
        return;

    IWL_DEBUG_TEMP(priv, "Queueing thermal throttling work.\n");
    queue_work(priv->workqueue, &priv->tt_work);
}

/* Thermal throttling initialization
 * For advance thermal throttling:
 *     Initialize Thermal Index and temperature threshold table
 *     Initialize thermal throttling restriction table
 */
void iwl_tt_initialize(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;
    int size = sizeof(struct iwl_tt_trans) * (IWL_TI_STATE_MAX - 1);
    struct iwl_tt_trans *transaction;

    IWL_DEBUG_TEMP(priv, "Initialize Thermal Throttling\n");

    memset(tt, 0, sizeof(struct iwl_tt_mgmt));

    tt->state = IWL_TI_0;
    init_timer(&priv->thermal_throttle.ct_kill_exit_tm);
    priv->thermal_throttle.ct_kill_exit_tm.data = (unsigned long)priv;
    priv->thermal_throttle.ct_kill_exit_tm.function =
        iwl_tt_check_exit_ct_kill;
    init_timer(&priv->thermal_throttle.ct_kill_waiting_tm);
    priv->thermal_throttle.ct_kill_waiting_tm.data =
        (unsigned long)priv;
    priv->thermal_throttle.ct_kill_waiting_tm.function =
        iwl_tt_ready_for_ct_kill;
    /* setup deferred ct kill work */
    INIT_WORK(&priv->tt_work, iwl_bg_tt_work);
    INIT_WORK(&priv->ct_enter, iwl_bg_ct_enter);
    INIT_WORK(&priv->ct_exit, iwl_bg_ct_exit);

    if (priv->cfg->base_params->adv_thermal_throttle) {
        IWL_DEBUG_TEMP(priv, "Advanced Thermal Throttling\n");
        tt->restriction = kcalloc(IWL_TI_STATE_MAX,
                      sizeof(struct iwl_tt_restriction),
                      GFP_KERNEL);
        tt->transaction = kcalloc(IWL_TI_STATE_MAX *
                      (IWL_TI_STATE_MAX - 1),
                      sizeof(struct iwl_tt_trans),
                      GFP_KERNEL);
        if (!tt->restriction || !tt->transaction) {
            IWL_ERR(priv, "Fallback to Legacy Throttling\n");
            priv->thermal_throttle.advanced_tt = false;
            kfree(tt->restriction);
            tt->restriction = NULL;
            kfree(tt->transaction);
            tt->transaction = NULL;
        } else {
            transaction = tt->transaction +
                (IWL_TI_0 * (IWL_TI_STATE_MAX - 1));
            memcpy(transaction, &tt_range_0[0], size);
            transaction = tt->transaction +
                (IWL_TI_1 * (IWL_TI_STATE_MAX - 1));
            memcpy(transaction, &tt_range_1[0], size);
            transaction = tt->transaction +
                (IWL_TI_2 * (IWL_TI_STATE_MAX - 1));
            memcpy(transaction, &tt_range_2[0], size);
            transaction = tt->transaction +
                (IWL_TI_CT_KILL * (IWL_TI_STATE_MAX - 1));
            memcpy(transaction, &tt_range_3[0], size);
            size = sizeof(struct iwl_tt_restriction) *
                IWL_TI_STATE_MAX;
            memcpy(tt->restriction,
                &restriction_range[0], size);
            priv->thermal_throttle.advanced_tt = true;
        }
    } else {
        IWL_DEBUG_TEMP(priv, "Legacy Thermal Throttling\n");
        priv->thermal_throttle.advanced_tt = false;
    }
}

/* cleanup thermal throttling management related memory and timer */
void iwl_tt_exit(struct iwl_priv *priv)
{
    struct iwl_tt_mgmt *tt = &priv->thermal_throttle;

    /* stop ct_kill_exit_tm timer if activated */
    del_timer_sync(&priv->thermal_throttle.ct_kill_exit_tm);
    /* stop ct_kill_waiting_tm timer if activated */
    del_timer_sync(&priv->thermal_throttle.ct_kill_waiting_tm);
    cancel_work_sync(&priv->tt_work);
    cancel_work_sync(&priv->ct_enter);
    cancel_work_sync(&priv->ct_exit);

    if (priv->thermal_throttle.advanced_tt) {
        /* free advance thermal throttling memory */
        kfree(tt->restriction);
        tt->restriction = NULL;
        kfree(tt->transaction);
        tt->transaction = NULL;
    }
}