drivers/net/wireless/ath9k/rc.h

   1 /*
   2  * Copyright (c) 2004 Sam Leffler, Errno Consulting
   3  * Copyright (c) 2004 Video54 Technologies, Inc.
   4  * Copyright (c) 2008 Atheros Communications Inc.
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #ifndef RC_H
  20 #define RC_H
  21
  22 #include "ath9k.h"
  23 /*
  24  * Interface definitions for transmit rate control modules for the
  25  * Atheros driver.
  26  *
  27  * A rate control module is responsible for choosing the transmit rate
  28  * for each data frame.  Management+control frames are always sent at
  29  * a fixed rate.
  30  *
  31  * Only one module may be present at a time; the driver references
  32  * rate control interfaces by symbol name.  If multiple modules are
  33  * to be supported we'll need to switch to a registration-based scheme
  34  * as is currently done, for example, for authentication modules.
  35  *
  36  * An instance of the rate control module is attached to each device
  37  * at attach time and detached when the device is destroyed.  The module
  38  * may associate data with each device and each node (station).  Both
  39  * sets of storage are opaque except for the size of the per-node storage
  40  * which must be provided when the module is attached.
  41  *
  42  * The rate control module is notified for each state transition and
  43  * station association/reassociation.  Otherwise it is queried for a
  44  * rate for each outgoing frame and provided status from each transmitted
  45  * frame.  Any ancillary processing is the responsibility of the module
  46  * (e.g. if periodic processing is required then the module should setup
  47  * it's own timer).
  48  *
  49  * In addition to the transmit rate for each frame the module must also
  50  * indicate the number of attempts to make at the specified rate.  If this
  51  * number is != ATH_TXMAXTRY then an additional callback is made to setup
  52  * additional transmit state.  The rate control code is assumed to write
  53  * this additional data directly to the transmit descriptor.
  54  */
  55
  56 struct ath_softc;
  57
  58 #define TRUE 1
  59 #define FALSE 0
  60
  61 #define ATH_RATE_MAX    30
  62
  63 enum ieee80211_fixed_rate_mode {
  64         IEEE80211_FIXED_RATE_NONE  = 0,
  65         IEEE80211_FIXED_RATE_MCS   = 1  /* HT rates */
  66 };
  67
  68 /*
  69  * Use the hal os glue code to get ms time
  70  */
  71 #define IEEE80211_RATE_IDX_ENTRY(val, idx) (((val&(0xff<<(idx*8)))>>(idx*8)))
  72
  73 #define WLAN_PHY_HT_20_SS       WLAN_RC_PHY_HT_20_SS
  74 #define WLAN_PHY_HT_20_DS       WLAN_RC_PHY_HT_20_DS
  75 #define WLAN_PHY_HT_20_DS_HGI   WLAN_RC_PHY_HT_20_DS_HGI
  76 #define WLAN_PHY_HT_40_SS       WLAN_RC_PHY_HT_40_SS
  77 #define WLAN_PHY_HT_40_SS_HGI   WLAN_RC_PHY_HT_40_SS_HGI
  78 #define WLAN_PHY_HT_40_DS       WLAN_RC_PHY_HT_40_DS
  79 #define WLAN_PHY_HT_40_DS_HGI   WLAN_RC_PHY_HT_40_DS_HGI
  80
  81 #define WLAN_PHY_OFDM   PHY_OFDM
  82 #define WLAN_PHY_CCK    PHY_CCK
  83
  84 #define TRUE_20         0x2
  85 #define TRUE_40         0x4
  86 #define TRUE_2040       (TRUE_20|TRUE_40)
  87 #define TRUE_ALL        (TRUE_2040|TRUE)
  88
  89 enum {
  90         WLAN_RC_PHY_HT_20_SS = 4,
  91         WLAN_RC_PHY_HT_20_DS,
  92         WLAN_RC_PHY_HT_40_SS,
  93         WLAN_RC_PHY_HT_40_DS,
  94         WLAN_RC_PHY_HT_20_SS_HGI,
  95         WLAN_RC_PHY_HT_20_DS_HGI,
  96         WLAN_RC_PHY_HT_40_SS_HGI,
  97         WLAN_RC_PHY_HT_40_DS_HGI,
  98         WLAN_RC_PHY_MAX
  99 };
 100
 101 #define WLAN_RC_PHY_DS(_phy)   ((_phy == WLAN_RC_PHY_HT_20_DS)          \
 102                                 || (_phy == WLAN_RC_PHY_HT_40_DS)       \
 103                                 || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)   \
 104                                 || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 105 #define WLAN_RC_PHY_40(_phy)   ((_phy == WLAN_RC_PHY_HT_40_SS)          \
 106                                 || (_phy == WLAN_RC_PHY_HT_40_DS)       \
 107                                 || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)   \
 108                                 || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 109 #define WLAN_RC_PHY_SGI(_phy)  ((_phy == WLAN_RC_PHY_HT_20_SS_HGI)      \
 110                                 || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)   \
 111                                 || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)   \
 112                                 || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 113
 114 #define WLAN_RC_PHY_HT(_phy)    (_phy >= WLAN_RC_PHY_HT_20_SS)
 115
 116 /* Returns the capflag mode */
 117 #define WLAN_RC_CAP_MODE(capflag) (((capflag & WLAN_RC_HT_FLAG) ?       \
 118                 (capflag & WLAN_RC_40_FLAG) ? TRUE_40 : TRUE_20 : TRUE))
 119
 120 /* Return TRUE if flag supports HT20 && client supports HT20 or
 121  * return TRUE if flag supports HT40 && client supports HT40.
 122  * This is used becos some rates overlap between HT20/HT40.
 123  */
 124
 125 #define WLAN_RC_PHY_HT_VALID(flag, capflag) (((flag & TRUE_20) && !(capflag \
 126                                 & WLAN_RC_40_FLAG)) || ((flag & TRUE_40) && \
 127                                   (capflag & WLAN_RC_40_FLAG)))
 128
 129 #define WLAN_RC_DS_FLAG         (0x01)
 130 #define WLAN_RC_40_FLAG         (0x02)
 131 #define WLAN_RC_SGI_FLAG        (0x04)
 132 #define WLAN_RC_HT_FLAG         (0x08)
 133
 134 #define RATE_TABLE_SIZE         64
 135
 136 /**
 137  * struct ath_rate_table - Rate Control table
 138  * @valid: valid for use in rate control
 139  * @valid_single_stream: valid for use in rate control for
 140  *      single stream operation
 141  * @phy: CCK/OFDM
 142  * @ratekbps: rate in Kbits per second
 143  * @user_ratekbps: user rate in Kbits per second
 144  * @ratecode: rate that goes into HW descriptors
 145  * @short_preamble: Mask for enabling short preamble in ratecode for CCK
 146  * @dot11rate: value that goes into supported
 147  *      rates info element of MLME
 148  * @ctrl_rate: Index of next lower basic rate, used for duration computation
 149  * @max_4ms_framelen: maximum frame length(bytes) for tx duration
 150  * @probe_interval: interval for rate control to probe for other rates
 151  * @rssi_reduce_interval: interval for rate control to reduce rssi
 152  * @initial_ratemax: initial ratemax value used in ath_rc_sib_update()
 153  */
 154 struct ath_rate_table {
 155         int rate_cnt;
 156         struct {
 157                 int valid;
 158                 int valid_single_stream;
 159                 u8 phy;
 160                 u32 ratekbps;
 161                 u32 user_ratekbps;
 162                 u8 ratecode;
 163                 u8 short_preamble;
 164                 u8 dot11rate;
 165                 u8 ctrl_rate;
 166                 int8_t rssi_ack_validmin;
 167                 int8_t rssi_ack_deltamin;
 168                 u8 base_index;
 169                 u8 cw40index;
 170                 u8 sgi_index;
 171                 u8 ht_index;
 172                 u32 max_4ms_framelen;
 173         } info[RATE_TABLE_SIZE];
 174         u32 probe_interval;
 175         u32 rssi_reduce_interval;
 176         u8 initial_ratemax;
 177 };
 178
 179 #define ATH_RC_PROBE_ALLOWED            0x00000001
 180 #define ATH_RC_MINRATE_LASTRATE         0x00000002
 181
 182 struct ath_rc_series {
 183         u8 rix;
 184         u8 tries;
 185         u8 flags;
 186         u32 max_4ms_framelen;
 187 };
 188
 189 /* rcs_flags definition */
 190 #define ATH_RC_DS_FLAG               0x01
 191 #define ATH_RC_CW40_FLAG             0x02    /* CW 40 */
 192 #define ATH_RC_SGI_FLAG              0x04    /* Short Guard Interval */
 193 #define ATH_RC_HT_FLAG               0x08    /* HT */
 194 #define ATH_RC_RTSCTS_FLAG           0x10    /* RTS-CTS */
 195
 196 /*
 197  * State structures for new rate adaptation code
 198  */
 199 #define MAX_TX_RATE_TBL         64
 200 #define MAX_TX_RATE_PHY         48
 201
 202 struct ath_tx_ratectrl_state {
 203         int8_t rssi_thres;      /* required rssi for this rate (dB) */
 204         u8 per;                 /* recent estimate of packet error rate (%) */
 205 };
 206
 207 /**
 208  * struct ath_tx_ratectrl - TX Rate control Information
 209  * @state: RC state
 210  * @rssi_last: last ACK rssi
 211  * @rssi_last_lookup: last ACK rssi used for lookup
 212  * @rssi_last_prev: previous last ACK rssi
 213  * @rssi_last_prev2: 2nd previous last ACK rssi
 214  * @rssi_sum_cnt: count of rssi_sum for averaging
 215  * @rssi_sum_rate: rate that we are averaging
 216  * @rssi_sum: running sum of rssi for averaging
 217  * @probe_rate: rate we are probing at
 218  * @rssi_time: msec timestamp for last ack rssi
 219  * @rssi_down_time: msec timestamp for last down step
 220  * @probe_time: msec timestamp for last probe
 221  * @hw_maxretry_pktcnt: num of packets since we got HW max retry error
 222  * @max_valid_rate: maximum number of valid rate
 223  * @per_down_time: msec timestamp for last PER down step
 224  * @valid_phy_ratecnt: valid rate count
 225  * @rate_max_phy: phy index for the max rate
 226  * @probe_interval: interval for ratectrl to probe for other rates
 227  */
 228 struct ath_tx_ratectrl {
 229         struct ath_tx_ratectrl_state state[MAX_TX_RATE_TBL];
 230         int8_t rssi_last;
 231         int8_t rssi_last_lookup;
 232         int8_t rssi_last_prev;
 233         int8_t rssi_last_prev2;
 234         int32_t rssi_sum_cnt;
 235         int32_t rssi_sum_rate;
 236         int32_t rssi_sum;
 237         u8 rate_table_size;
 238         u8 probe_rate;
 239         u32 rssi_time;
 240         u32 rssi_down_time;
 241         u32 probe_time;
 242         u8 hw_maxretry_pktcnt;
 243         u8 max_valid_rate;
 244         u8 valid_rate_index[MAX_TX_RATE_TBL];
 245         u32 per_down_time;
 246
 247         /* 11n state */
 248         u8 valid_phy_ratecnt[WLAN_RC_PHY_MAX];
 249         u8 valid_phy_rateidx[WLAN_RC_PHY_MAX][MAX_TX_RATE_TBL];
 250         u8 rc_phy_mode;
 251         u8 rate_max_phy;
 252         u32 probe_interval;
 253 };
 254
 255 struct ath_rateset {
 256         u8 rs_nrates;
 257         u8 rs_rates[ATH_RATE_MAX];
 258 };
 259
 260 /* per-device state */
 261 struct ath_rate_softc {
 262         /* phy tables that contain rate control data */
 263         const void *hw_rate_table[ATH9K_MODE_MAX];
 264
 265         /* -1 or index of fixed rate */
 266         int fixedrix;
 267 };
 268
 269 /* per-node state */
 270 struct ath_rate_node {
 271         struct ath_tx_ratectrl tx_ratectrl;
 272
 273         /* rate idx of last data frame */
 274         u32 prev_data_rix;
 275
 276         /* ht capabilities */
 277         u8 ht_cap;
 278
 279         /* When TRUE, only single stream Tx possible */
 280         u8 single_stream;
 281
 282         /* Negotiated rates */
 283         struct ath_rateset neg_rates;
 284
 285         /* Negotiated HT rates */
 286         struct ath_rateset neg_ht_rates;
 287
 288         struct ath_rate_softc *asc;
 289         struct ath_vap *avp;
 290 };
 291
 292 /* Driver data of ieee80211_tx_info */
 293 struct ath_tx_info_priv {
 294         struct ath_rc_series rcs[4];
 295         struct ath_tx_status tx;
 296         int n_frames;
 297         int n_bad_frames;
 298         u8 min_rate;
 299 };
 300
 301 /*
 302  * Attach/detach a rate control module.
 303  */
 304 struct ath_rate_softc *ath_rate_attach(struct ath_hal *ah);
 305 void ath_rate_detach(struct ath_rate_softc *asc);
 306
 307 /*
 308  * Update/reset rate control state for 802.11 state transitions.
 309  * Important mostly as the analog to ath_rate_newassoc when operating
 310  * in station mode.
 311  */
 312 void ath_rc_node_update(struct ieee80211_hw *hw, struct ath_rate_node *rc_priv);
 313 void ath_rate_newstate(struct ath_softc *sc, struct ath_vap *avp);
 314
 315 /*
 316  * Return rate index for given Dot11 Rate.
 317  */
 318 u8 ath_rate_findrateix(struct ath_softc *sc,
 319                        u8 dot11_rate);
 320
 321 /* Routines to register/unregister rate control algorithm */
 322 int ath_rate_control_register(void);
 323 void ath_rate_control_unregister(void);
 324
 325 #endif /* RC_H */