/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH
 * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
 *
 * 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 COPYING.
 *
 * Contact Information:
 *  Intel Linux Wireless <linuxwifi@intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 * BSD LICENSE
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH
 * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 *****************************************************************************/

#include <net/mac80211.h>
#include "fw-api.h"
#include "mvm.h"

#define QUOTA_100       IWL_MVM_MAX_QUOTA
#define QUOTA_LOWLAT_MIN ((QUOTA_100 * IWL_MVM_LOWLAT_QUOTA_MIN_PERCENT) / 100)

struct iwl_mvm_quota_iterator_data {
        int n_interfaces[MAX_BINDINGS];
        int colors[MAX_BINDINGS];
        int low_latency[MAX_BINDINGS];
#ifdef CONFIG_IWLWIFI_DEBUGFS
        int dbgfs_min[MAX_BINDINGS];
#endif
        int n_low_latency_bindings;
        struct ieee80211_vif *disabled_vif;
};

static void iwl_mvm_quota_iterator(void *_data, u8 *mac,
                                   struct ieee80211_vif *vif)
{
        struct iwl_mvm_quota_iterator_data *data = _data;
        struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
        u16 id;

        /* skip disabled interfaces here immediately */
        if (vif == data->disabled_vif)
                return;

        if (!mvmvif->phy_ctxt)
                return;

        /* currently, PHY ID == binding ID */
        id = mvmvif->phy_ctxt->id;

        /* need at least one binding per PHY */
        BUILD_BUG_ON(NUM_PHY_CTX > MAX_BINDINGS);

        if (WARN_ON_ONCE(id >= MAX_BINDINGS))
                return;

        switch (vif->type) {
        case NL80211_IFTYPE_STATION:
                if (vif->bss_conf.assoc)
                        break;
                return;
        case NL80211_IFTYPE_AP:
        case NL80211_IFTYPE_ADHOC:
                if (mvmvif->ap_ibss_active)
                        break;
                return;
        case NL80211_IFTYPE_MONITOR:
                if (mvmvif->monitor_active)
                        break;
                return;
        case NL80211_IFTYPE_P2P_DEVICE:
                return;
        default:
                WARN_ON_ONCE(1);
                return;
        }

        if (data->colors[id] < 0)
                data->colors[id] = mvmvif->phy_ctxt->color;
        else
                WARN_ON_ONCE(data->colors[id] != mvmvif->phy_ctxt->color);

        data->n_interfaces[id]++;

#ifdef CONFIG_IWLWIFI_DEBUGFS
        if (mvmvif->dbgfs_quota_min)
                data->dbgfs_min[id] = max(data->dbgfs_min[id],
                                          mvmvif->dbgfs_quota_min);
#endif

        if (iwl_mvm_vif_low_latency(mvmvif) && !data->low_latency[id]) {
                data->n_low_latency_bindings++;
                data->low_latency[id] = true;
        }
}

static void iwl_mvm_adjust_quota_for_noa(struct iwl_mvm *mvm,
                                         struct iwl_time_quota_cmd *cmd)
{
#ifdef CONFIG_NL80211_TESTMODE
        struct iwl_mvm_vif *mvmvif;
        int i, phy_id = -1, beacon_int = 0;

        if (!mvm->noa_duration || !mvm->noa_vif)
                return;

        mvmvif = iwl_mvm_vif_from_mac80211(mvm->noa_vif);
        if (!mvmvif->ap_ibss_active)
                return;

        phy_id = mvmvif->phy_ctxt->id;
        beacon_int = mvm->noa_vif->bss_conf.beacon_int;

        for (i = 0; i < MAX_BINDINGS; i++) {
                struct iwl_time_quota_data *data =
                                        iwl_mvm_quota_cmd_get_quota(mvm, cmd,
                                                                    i);
                u32 id_n_c = le32_to_cpu(data->id_and_color);
                u32 id = (id_n_c & FW_CTXT_ID_MSK) >> FW_CTXT_ID_POS;
                u32 quota = le32_to_cpu(data->quota);

                if (id != phy_id)
                        continue;

                quota *= (beacon_int - mvm->noa_duration);
                quota /= beacon_int;

                IWL_DEBUG_QUOTA(mvm, "quota: adjust for NoA from %d to %d\n",
                                le32_to_cpu(data->quota), quota);

                data->quota = cpu_to_le32(quota);
        }
#endif
}

int iwl_mvm_update_quotas(struct iwl_mvm *mvm,
                          bool force_update,
                          struct ieee80211_vif *disabled_vif)
{
        struct iwl_time_quota_cmd cmd = {};
        int i, idx, err, num_active_macs, quota, quota_rem, n_non_lowlat;
        struct iwl_mvm_quota_iterator_data data = {
                .n_interfaces = {},
                .colors = { -1, -1, -1, -1 },
                .disabled_vif = disabled_vif,
        };
        struct iwl_time_quota_cmd *last = &mvm->last_quota_cmd;
        struct iwl_time_quota_data *qdata, *last_data;
        bool send = false;

        lockdep_assert_held(&mvm->mutex);

        /* update all upon completion */
        if (test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status))
                return 0;

        /* iterator data above must match */
        BUILD_BUG_ON(MAX_BINDINGS != 4);

        ieee80211_iterate_active_interfaces_atomic(
                mvm->hw, IEEE80211_IFACE_ITER_NORMAL,
                iwl_mvm_quota_iterator, &data);

        /*
         * The FW's scheduling session consists of
         * IWL_MVM_MAX_QUOTA fragments. Divide these fragments
         * equally between all the bindings that require quota
         */
        num_active_macs = 0;
        for (i = 0; i < MAX_BINDINGS; i++) {
                qdata = iwl_mvm_quota_cmd_get_quota(mvm, &cmd, i);
                qdata->id_and_color = cpu_to_le32(FW_CTXT_INVALID);
                num_active_macs += data.n_interfaces[i];
        }

        n_non_lowlat = num_active_macs;

        if (data.n_low_latency_bindings == 1) {
                for (i = 0; i < MAX_BINDINGS; i++) {
                        if (data.low_latency[i]) {
                                n_non_lowlat -= data.n_interfaces[i];
                                break;
                        }
                }
        }

        if (data.n_low_latency_bindings == 1 && n_non_lowlat) {
                /*
                 * Reserve quota for the low latency binding in case that
                 * there are several data bindings but only a single
                 * low latency one. Split the rest of the quota equally
                 * between the other data interfaces.
                 */
                quota = (QUOTA_100 - QUOTA_LOWLAT_MIN) / n_non_lowlat;
                quota_rem = QUOTA_100 - n_non_lowlat * quota -
                            QUOTA_LOWLAT_MIN;
                IWL_DEBUG_QUOTA(mvm,
                                "quota: low-latency binding active, remaining quota per other binding: %d\n",
                                quota);
        } else if (num_active_macs) {
                /*
                 * There are 0 or more than 1 low latency bindings, or all the
                 * data interfaces belong to the single low latency binding.
                 * Split the quota equally between the data interfaces.
                 */
                quota = QUOTA_100 / num_active_macs;
                quota_rem = QUOTA_100 % num_active_macs;
                IWL_DEBUG_QUOTA(mvm,
                                "quota: splitting evenly per binding: %d\n",
                                quota);
        } else {
                /* values don't really matter - won't be used */
                quota = 0;
                quota_rem = 0;
        }

        for (idx = 0, i = 0; i < MAX_BINDINGS; i++) {
                if (data.colors[i] < 0)
                        continue;

                qdata = iwl_mvm_quota_cmd_get_quota(mvm, &cmd, idx);

                qdata->id_and_color =
                        cpu_to_le32(FW_CMD_ID_AND_COLOR(i, data.colors[i]));

                if (data.n_interfaces[i] <= 0)
                        qdata->quota = cpu_to_le32(0);
#ifdef CONFIG_IWLWIFI_DEBUGFS
                else if (data.dbgfs_min[i])
                        qdata->quota =
                                cpu_to_le32(data.dbgfs_min[i] * QUOTA_100 / 100);
#endif
                else if (data.n_low_latency_bindings == 1 && n_non_lowlat &&
                         data.low_latency[i])
                        /*
                         * There is more than one binding, but only one of the
                         * bindings is in low latency. For this case, allocate
                         * the minimal required quota for the low latency
                         * binding.
                         */
                        qdata->quota = cpu_to_le32(QUOTA_LOWLAT_MIN);
                else
                        qdata->quota =
                                cpu_to_le32(quota * data.n_interfaces[i]);

                WARN_ONCE(le32_to_cpu(qdata->quota) > QUOTA_100,
                          "Binding=%d, quota=%u > max=%u\n",
                          idx, le32_to_cpu(qdata->quota), QUOTA_100);

                qdata->max_duration = cpu_to_le32(0);

                idx++;
        }

        /* Give the remainder of the session to the first data binding */
        for (i = 0; i < MAX_BINDINGS; i++) {
                qdata = iwl_mvm_quota_cmd_get_quota(mvm, &cmd, i);
                if (le32_to_cpu(qdata->quota) != 0) {
                        le32_add_cpu(&qdata->quota, quota_rem);
                        IWL_DEBUG_QUOTA(mvm,
                                        "quota: giving remainder of %d to binding %d\n",
                                        quota_rem, i);
                        break;
                }
        }

        iwl_mvm_adjust_quota_for_noa(mvm, &cmd);

        /* check that we have non-zero quota for all valid bindings */
        for (i = 0; i < MAX_BINDINGS; i++) {
                qdata = iwl_mvm_quota_cmd_get_quota(mvm, &cmd, i);
                last_data = iwl_mvm_quota_cmd_get_quota(mvm, last, i);
                if (qdata->id_and_color != last_data->id_and_color)
                        send = true;
                if (qdata->max_duration != last_data->max_duration)
                        send = true;
                if (abs((int)le32_to_cpu(qdata->quota) -
                        (int)le32_to_cpu(last_data->quota))
                                                > IWL_MVM_QUOTA_THRESHOLD)
                        send = true;
                if (qdata->id_and_color == cpu_to_le32(FW_CTXT_INVALID))
                        continue;
                WARN_ONCE(qdata->quota == 0,
                          "zero quota on binding %d\n", i);
        }

        if (!send && !force_update) {
                /* don't send a practically unchanged command, the firmware has
                 * to re-initialize a lot of state and that can have an adverse
                 * impact on it
                 */
                return 0;
        }

        err = iwl_mvm_send_cmd_pdu(mvm, TIME_QUOTA_CMD, 0,
                                   iwl_mvm_quota_cmd_size(mvm), &cmd);

        if (err)
                IWL_ERR(mvm, "Failed to send quota: %d\n", err);
        else
                mvm->last_quota_cmd = cmd;
        return err;
}