diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/mvm/sta.h')
-rw-r--r-- | drivers/net/wireless/iwlwifi/mvm/sta.h | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/mvm/sta.h b/drivers/net/wireless/iwlwifi/mvm/sta.h new file mode 100644 index 0000000..1bf3010 --- /dev/null +++ b/drivers/net/wireless/iwlwifi/mvm/sta.h @@ -0,0 +1,368 @@ +/****************************************************************************** + * + * 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 - 2013 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 LICENSE.GPL. + * + * 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 - 2013 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 + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + *****************************************************************************/ + +#ifndef __sta_h__ +#define __sta_h__ + +#include <linux/spinlock.h> +#include <net/mac80211.h> +#include <linux/wait.h> + +#include "iwl-trans.h" /* for IWL_MAX_TID_COUNT */ +#include "fw-api.h" /* IWL_MVM_STATION_COUNT */ +#include "rs.h" + +struct iwl_mvm; + +/** + * DOC: station table - introduction + * + * The station table is a list of data structure that reprensent the stations. + * In STA/P2P client mode, the driver will hold one station for the AP/ GO. + * In GO/AP mode, the driver will have as many stations as associated clients. + * All these stations are reflected in the fw's station table. The driver + * keeps the fw's station table up to date with the ADD_STA command. Stations + * can be removed by the REMOVE_STA command. + * + * All the data related to a station is held in the structure %iwl_mvm_sta + * which is embed in the mac80211's %ieee80211_sta (in the drv_priv) area. + * This data includes the index of the station in the fw, per tid information + * (sequence numbers, Block-ack state machine, etc...). The stations are + * created and deleted by the %sta_state callback from %ieee80211_ops. + * + * The driver holds a map: %fw_id_to_mac_id that allows to fetch a + * %ieee80211_sta (and the %iwl_mvm_sta embedded into it) based on a fw + * station index. That way, the driver is able to get the tid related data in + * O(1) in time sensitive paths (Tx / Tx response / BA notification). These + * paths are triggered by the fw, and the driver needs to get a pointer to the + * %ieee80211 structure. This map helps to get that pointer quickly. + */ + +/** + * DOC: station table - locking + * + * As stated before, the station is created / deleted by mac80211's %sta_state + * callback from %ieee80211_ops which can sleep. The next paragraph explains + * the locking of a single stations, the next ones relates to the station + * table. + * + * The station holds the sequence number per tid. So this data needs to be + * accessed in the Tx path (which is softIRQ). It also holds the Block-Ack + * information (the state machine / and the logic that checks if the queues + * were drained), so it also needs to be accessible from the Tx response flow. + * In short, the station needs to be access from sleepable context as well as + * from tasklets, so the station itself needs a spinlock. + * + * The writers of %fw_id_to_mac_id map are serialized by the global mutex of + * the mvm op_mode. This is possible since %sta_state can sleep. + * The pointers in this map are RCU protected, hence we won't replace the + * station while we have Tx / Tx response / BA notification running. + * + * If a station is deleted while it still has packets in its A-MPDU queues, + * then the reclaim flow will notice that there is no station in the map for + * sta_id and it will dump the responses. + */ + +/** + * DOC: station table - internal stations + * + * The FW needs a few internal stations that are not reflected in + * mac80211, such as broadcast station in AP / GO mode, or AUX sta for + * scanning and P2P device (during the GO negotiation). + * For these kind of stations we have %iwl_mvm_int_sta struct which holds the + * data relevant for them from both %iwl_mvm_sta and %ieee80211_sta. + * Usually the data for these stations is static, so no locking is required, + * and no TID data as this is also not needed. + * One thing to note, is that these stations have an ID in the fw, but not + * in mac80211. In order to "reserve" them a sta_id in %fw_id_to_mac_id + * we fill ERR_PTR(EINVAL) in this mapping and all other dereferencing of + * pointers from this mapping need to check that the value is not error + * or NULL. + * + * Currently there is only one auxiliary station for scanning, initialized + * on init. + */ + +/** + * DOC: station table - AP Station in STA mode + * + * %iwl_mvm_vif includes the index of the AP station in the fw's STA table: + * %ap_sta_id. To get the point to the coresponsding %ieee80211_sta, + * &fw_id_to_mac_id can be used. Due to the way the fw works, we must not remove + * the AP station from the fw before setting the MAC context as unassociated. + * Hence, %fw_id_to_mac_id[%ap_sta_id] will be NULLed when the AP station is + * removed by mac80211, but the station won't be removed in the fw until the + * VIF is set as unassociated. Then, %ap_sta_id will be invalidated. + */ + +/** + * DOC: station table - Drain vs. Flush + * + * Flush means that all the frames in the SCD queue are dumped regardless the + * station to which they were sent. We do that when we disassociate and before + * we remove the STA of the AP. The flush can be done synchronously against the + * fw. + * Drain means that the fw will drop all the frames sent to a specific station. + * This is useful when a client (if we are IBSS / GO or AP) disassociates. In + * that case, we need to drain all the frames for that client from the AC queues + * that are shared with the other clients. Only then, we can remove the STA in + * the fw. In order to do so, we track the non-AMPDU packets for each station. + * If mac80211 removes a STA and if it still has non-AMPDU packets pending in + * the queues, we mark this station as %EBUSY in %fw_id_to_mac_id, and drop all + * the frames for this STA (%iwl_mvm_rm_sta). When the last frame is dropped + * (we know about it with its Tx response), we remove the station in fw and set + * it as %NULL in %fw_id_to_mac_id: this is the purpose of + * %iwl_mvm_sta_drained_wk. + */ + +/** + * DOC: station table - fw restart + * + * When the fw asserts, or we have any other issue that requires to reset the + * driver, we require mac80211 to reconfigure the driver. Since the private + * data of the stations is embed in mac80211's %ieee80211_sta, that data will + * not be zeroed and needs to be reinitialized manually. + * %IWL_MVM_STATUS_IN_HW_RESTART is set during restart and that will hint us + * that we must not allocate a new sta_id but reuse the previous one. This + * means that the stations being re-added after the reset will have the same + * place in the fw as before the reset. We do need to zero the %fw_id_to_mac_id + * map, since the stations aren't in the fw any more. Internal stations that + * are not added by mac80211 will be re-added in the init flow that is called + * after the restart: mac80211 call's %iwl_mvm_mac_start which calls to + * %iwl_mvm_up. + */ + +/** + * DOC: AP mode - PS + * + * When a station is asleep, the fw will set it as "asleep". All the + * non-aggregation frames to that station will be dropped by the fw + * (%TX_STATUS_FAIL_DEST_PS failure code). + * AMPDUs are in a separate queue that is stopped by the fw. We just need to + * let mac80211 know how many frames we have in these queues so that it can + * properly handle trigger frames. + * When the a trigger frame is received, mac80211 tells the driver to send + * frames from the AMPDU queues or AC queue depending on which queue are + * delivery-enabled and what TID has frames to transmit (Note that mac80211 has + * all the knowledege since all the non-agg frames are buffered / filtered, and + * the driver tells mac80211 about agg frames). The driver needs to tell the fw + * to let frames out even if the station is asleep. This is done by + * %iwl_mvm_sta_modify_sleep_tx_count. + * When we receive a frame from that station with PM bit unset, the + * driver needs to let the fw know that this station isn't alseep any more. + * This is done by %iwl_mvm_sta_modify_ps_wake. + * + * TODO - EOSP handling + */ + +/** + * enum iwl_mvm_agg_state + * + * The state machine of the BA agreement establishment / tear down. + * These states relate to a specific RA / TID. + * + * @IWL_AGG_OFF: aggregation is not used + * @IWL_AGG_STARTING: aggregation are starting (between start and oper) + * @IWL_AGG_ON: aggregation session is up + * @IWL_EMPTYING_HW_QUEUE_ADDBA: establishing a BA session - waiting for the + * HW queue to be empty from packets for this RA /TID. + * @IWL_EMPTYING_HW_QUEUE_DELBA: tearing down a BA session - waiting for the + * HW queue to be empty from packets for this RA /TID. + */ +enum iwl_mvm_agg_state { + IWL_AGG_OFF = 0, + IWL_AGG_STARTING, + IWL_AGG_ON, + IWL_EMPTYING_HW_QUEUE_ADDBA, + IWL_EMPTYING_HW_QUEUE_DELBA, +}; + +/** + * struct iwl_mvm_tid_data - holds the states for each RA / TID + * @seq_number: the next WiFi sequence number to use + * @next_reclaimed: the WiFi sequence number of the next packet to be acked. + * This is basically (last acked packet++). + * @rate_n_flags: Rate at which Tx was attempted. Holds the data between the + * Tx response (TX_CMD), and the block ack notification (COMPRESSED_BA). + * @state: state of the BA agreement establishment / tear down. + * @txq_id: Tx queue used by the BA session + * @ssn: the first packet to be sent in AGG HW queue in Tx AGG start flow, or + * the first packet to be sent in legacy HW queue in Tx AGG stop flow. + * Basically when next_reclaimed reaches ssn, we can tell mac80211 that + * we are ready to finish the Tx AGG stop / start flow. + * @wait_for_ba: Expect block-ack before next Tx reply + */ +struct iwl_mvm_tid_data { + u16 seq_number; + u16 next_reclaimed; + /* The rest is Tx AGG related */ + u32 rate_n_flags; + enum iwl_mvm_agg_state state; + u16 txq_id; + u16 ssn; + bool wait_for_ba; +}; + +/** + * struct iwl_mvm_sta - representation of a station in the driver + * @sta_id: the index of the station in the fw (will be replaced by id_n_color) + * @tfd_queue_msk: the tfd queues used by the station + * @mac_id_n_color: the MAC context this station is linked to + * @tid_disable_agg: bitmap: if bit(tid) is set, the fw won't send ampdus for + * tid. + * @max_agg_bufsize: the maximal size of the AGG buffer for this station + * @lock: lock to protect the whole struct. Since %tid_data is access from Tx + * and from Tx response flow, it needs a spinlock. + * @pending_frames: number of frames for this STA on the shared Tx queues. + * @tid_data: per tid data. Look at %iwl_mvm_tid_data. + * + * When mac80211 creates a station it reserves some space (hw->sta_data_size) + * in the structure for use by driver. This structure is placed in that + * space. + * + */ +struct iwl_mvm_sta { + u32 sta_id; + u32 tfd_queue_msk; + u32 mac_id_n_color; + u16 tid_disable_agg; + u8 max_agg_bufsize; + spinlock_t lock; + atomic_t pending_frames; + struct iwl_mvm_tid_data tid_data[IWL_MAX_TID_COUNT]; + struct iwl_lq_sta lq_sta; + struct ieee80211_vif *vif; + +#ifdef CONFIG_PM_SLEEP + u16 last_seq_ctl; +#endif +}; + +/** + * struct iwl_mvm_int_sta - representation of an internal station (auxiliary or + * broadcast) + * @sta_id: the index of the station in the fw (will be replaced by id_n_color) + * @tfd_queue_msk: the tfd queues used by the station + */ +struct iwl_mvm_int_sta { + u32 sta_id; + u32 tfd_queue_msk; +}; + +int iwl_mvm_sta_add_to_fw(struct iwl_mvm *mvm, struct ieee80211_sta *sta); +int iwl_mvm_add_sta(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta); +int iwl_mvm_rm_sta(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta); +int iwl_mvm_rm_sta_id(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + u8 sta_id); +int iwl_mvm_set_sta_key(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta, + struct ieee80211_key_conf *key, + bool have_key_offset); +int iwl_mvm_remove_sta_key(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta, + struct ieee80211_key_conf *keyconf); + +void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm, + struct ieee80211_vif *vif, + struct ieee80211_key_conf *keyconf, + struct ieee80211_sta *sta, u32 iv32, + u16 *phase1key); + +/* AMPDU */ +int iwl_mvm_sta_rx_agg(struct iwl_mvm *mvm, struct ieee80211_sta *sta, + int tid, u16 ssn, bool start); +int iwl_mvm_sta_tx_agg_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif, + struct ieee80211_sta *sta, u16 tid, u16 *ssn); +int iwl_mvm_sta_tx_agg_oper(struct iwl_mvm *mvm, struct ieee80211_vif *vif, + struct ieee80211_sta *sta, u16 tid, u8 buf_size); +int iwl_mvm_sta_tx_agg_stop(struct iwl_mvm *mvm, struct ieee80211_vif *vif, + struct ieee80211_sta *sta, u16 tid); + +int iwl_mvm_add_aux_sta(struct iwl_mvm *mvm); +int iwl_mvm_allocate_int_sta(struct iwl_mvm *mvm, struct iwl_mvm_int_sta *sta, + u32 qmask); +void iwl_mvm_dealloc_int_sta(struct iwl_mvm *mvm, + struct iwl_mvm_int_sta *sta); +int iwl_mvm_send_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif, + struct iwl_mvm_int_sta *bsta); +int iwl_mvm_send_rm_bcast_sta(struct iwl_mvm *mvm, + struct iwl_mvm_int_sta *bsta); +int iwl_mvm_add_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif, + struct iwl_mvm_int_sta *bsta); +int iwl_mvm_rm_bcast_sta(struct iwl_mvm *mvm, struct iwl_mvm_int_sta *bsta); +void iwl_mvm_sta_drained_wk(struct work_struct *wk); +void iwl_mvm_sta_modify_ps_wake(struct iwl_mvm *mvm, int sta_id); +void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm, int sta_id, + enum ieee80211_frame_release_type reason, + u16 cnt); +int iwl_mvm_drain_sta(struct iwl_mvm *mvm, struct iwl_mvm_sta *mvmsta, + bool drain); + +#endif /* __sta_h__ */ |