path: root/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c

/******************************************************************************
 *
 * 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.
 *
 * 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 <ilw@linux.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.
 * 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
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * 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
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * 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.
 *
 *****************************************************************************/

#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include "iwl-io.h"
#include "iwl-prph.h"
#include "fw-api.h"
#include "mvm.h"

const u8 iwl_mvm_ac_to_tx_fifo[] = {
	IWL_MVM_TX_FIFO_VO,
	IWL_MVM_TX_FIFO_VI,
	IWL_MVM_TX_FIFO_BE,
	IWL_MVM_TX_FIFO_BK,
};

struct iwl_mvm_mac_iface_iterator_data {
	struct iwl_mvm *mvm;
	struct ieee80211_vif *vif;
	unsigned long available_mac_ids[BITS_TO_LONGS(NUM_MAC_INDEX_DRIVER)];
	unsigned long available_tsf_ids[BITS_TO_LONGS(NUM_TSF_IDS)];
	unsigned long used_hw_queues[BITS_TO_LONGS(IWL_MVM_MAX_QUEUES)];
	enum iwl_tsf_id preferred_tsf;
	bool found_vif;
};

static void iwl_mvm_mac_tsf_id_iter(void *_data, u8 *mac,
				    struct ieee80211_vif *vif)
{
	struct iwl_mvm_mac_iface_iterator_data *data = _data;
	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
	u16 min_bi;

	/* Skip the interface for which we are trying to assign a tsf_id  */
	if (vif == data->vif)
		return;

	/*
	 * The TSF is a hardware/firmware resource, there are 4 and
	 * the driver should assign and free them as needed. However,
	 * there are cases where 2 MACs should share the same TSF ID
	 * for the purpose of clock sync, an optimization to avoid
	 * clock drift causing overlapping TBTTs/DTIMs for a GO and
	 * client in the system.
	 *
	 * The firmware will decide according to the MAC type which
	 * will be the master and slave. Clients that need to sync
	 * with a remote station will be the master, and an AP or GO
	 * will be the slave.
	 *
	 * Depending on the new interface type it can be slaved to
	 * or become the master of an existing interface.
	 */
	switch (data->vif->type) {
	case NL80211_IFTYPE_STATION:
		/*
		 * The new interface is a client, so if the one we're iterating
		 * is an AP, and the beacon interval of the AP is a multiple or
		 * divisor of the beacon interval of the client, the same TSF
		 * should be used to avoid drift between the new client and
		 * existing AP. The existing AP will get drift updates from the
		 * new client context in this case.
		 */
		if (vif->type != NL80211_IFTYPE_AP ||
		    data->preferred_tsf != NUM_TSF_IDS ||
		    !test_bit(mvmvif->tsf_id, data->