package/ath9k/src/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 #define MCS_SET_SIZE    128
  63
  64 enum ieee80211_fixed_rate_mode {
  65         IEEE80211_FIXED_RATE_NONE  = 0,
  66         IEEE80211_FIXED_RATE_MCS   = 1  /* HT rates */
  67 };
  68
  69 /*
  70  * Use the hal os glue code to get ms time
  71  */
  72 #define IEEE80211_RATE_IDX_ENTRY(val, idx) (((val&(0xff<<(idx*8)))>>(idx*8)))
  73
  74 #define SHORT_PRE 1
  75 #define LONG_PRE 0
  76
  77 #define WLAN_PHY_HT_20_SS       WLAN_RC_PHY_HT_20_SS
  78 #define WLAN_PHY_HT_20_DS       WLAN_RC_PHY_HT_20_DS
  79 #define WLAN_PHY_HT_20_DS_HGI   WLAN_RC_PHY_HT_20_DS_HGI
  80 #define WLAN_PHY_HT_40_SS       WLAN_RC_PHY_HT_40_SS
  81 #define WLAN_PHY_HT_40_SS_HGI   WLAN_RC_PHY_HT_40_SS_HGI
  82 #define WLAN_PHY_HT_40_DS       WLAN_RC_PHY_HT_40_DS
  83 #define WLAN_PHY_HT_40_DS_HGI   WLAN_RC_PHY_HT_40_DS_HGI
  84
  85 #define WLAN_PHY_OFDM   PHY_OFDM
  86 #define WLAN_PHY_CCK    PHY_CCK
  87
  88 #define TRUE_20         0x2
  89 #define TRUE_40         0x4
  90 #define TRUE_2040       (TRUE_20|TRUE_40)
  91 #define TRUE_ALL        (TRUE_2040|TRUE)
  92
  93 enum {
  94         WLAN_RC_PHY_HT_20_SS = 4,
  95         WLAN_RC_PHY_HT_20_DS,
  96         WLAN_RC_PHY_HT_40_SS,
  97         WLAN_RC_PHY_HT_40_DS,
  98         WLAN_RC_PHY_HT_20_SS_HGI,
  99         WLAN_RC_PHY_HT_20_DS_HGI,
 100         WLAN_RC_PHY_HT_40_SS_HGI,
 101         WLAN_RC_PHY_HT_40_DS_HGI,
 102         WLAN_RC_PHY_MAX
 103 };
 104
 105 #define WLAN_RC_PHY_DS(_phy)   ((_phy == WLAN_RC_PHY_HT_20_DS)           \
 106         || (_phy == WLAN_RC_PHY_HT_40_DS)        \
 107         || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)    \
 108         || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 109 #define WLAN_RC_PHY_40(_phy)   ((_phy == WLAN_RC_PHY_HT_40_SS)           \
 110         || (_phy == WLAN_RC_PHY_HT_40_DS)        \
 111         || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)    \
 112         || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 113 #define WLAN_RC_PHY_SGI(_phy)  ((_phy == WLAN_RC_PHY_HT_20_SS_HGI)      \
 114         || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)   \
 115         || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)   \
 116         || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
 117
 118 #define WLAN_RC_PHY_HT(_phy)    (_phy >= WLAN_RC_PHY_HT_20_SS)
 119
 120 /* Returns the capflag mode */
 121 #define WLAN_RC_CAP_MODE(capflag) (((capflag & WLAN_RC_HT_FLAG)?        \
 122                 (capflag & WLAN_RC_40_FLAG)?TRUE_40:TRUE_20:\
 123                 TRUE))
 124
 125 /* Return TRUE if flag supports HT20 && client supports HT20 or
 126  * return TRUE if flag supports HT40 && client supports HT40.
 127  * This is used becos some rates overlap between HT20/HT40.
 128  */
 129
 130 #define WLAN_RC_PHY_HT_VALID(flag, capflag) (((flag & TRUE_20) && !(capflag \
 131                                 & WLAN_RC_40_FLAG)) || ((flag & TRUE_40) && \
 132                                   (capflag & WLAN_RC_40_FLAG)))
 133
 134 #define WLAN_RC_DS_FLAG         (0x01)
 135 #define WLAN_RC_40_FLAG         (0x02)
 136 #define WLAN_RC_SGI_FLAG        (0x04)
 137 #define WLAN_RC_HT_FLAG         (0x08)
 138
 139 /* Index into the rate table */
 140 #define INIT_RATE_MAX_20        23
 141 #define INIT_RATE_MAX_40        40
 142
 143 #define RATE_TABLE_SIZE         64
 144
 145 /* XXX: Convert to kdoc */
 146 struct ath_rate_table {
 147         int rate_cnt;
 148         struct {
 149                 int valid;            /* Valid for use in rate control */
 150                 int valid_single_stream;/* Valid for use in rate control
 151                                         for single stream operation */
 152                 u8 phy;              /* CCK/OFDM/TURBO/XR */
 153                 u32 ratekbps;         /* Rate in Kbits per second */
 154                 u32 user_ratekbps;     /* User rate in KBits per second */
 155                 u8 ratecode;         /* rate that goes into
 156                                         hw descriptors */
 157                 u8 short_preamble;    /* Mask for enabling short preamble
 158                                                 in rate code for CCK */
 159                 u8 dot11rate;        /* Value that goes into supported
 160                                         rates info element of MLME */
 161                 u8 ctrl_rate;      /* Index of next lower basic rate,
 162                                         used for duration computation */
 163                 int8_t rssi_ack_validmin;  /* Rate control related */
 164                 int8_t rssi_ack_deltamin;  /* Rate control related */
 165                 u8 base_index;        /* base rate index */
 166                 u8 cw40index;        /* 40cap rate index */
 167                 u8 sgi_index;         /* shortgi rate index */
 168                 u8 ht_index;          /* shortgi rate index */
 169                 u32 max_4ms_framelen;   /* Maximum frame length(bytes)
 170                                                 for 4ms tx duration */
 171         } info[RATE_TABLE_SIZE];
 172         u32 probe_interval;        /* interval for ratectrl to
 173                                         probe for other rates */
 174         u32 rssi_reduce_interval;   /* interval for ratectrl
 175                                                 to reduce RSSI */
 176         u8 initial_ratemax;   /* the initial ratemax value used
 177                                         in ath_rc_sib_update() */
 178 };
 179
 180 #define ATH_RC_PROBE_ALLOWED            0x00000001
 181 #define ATH_RC_MINRATE_LASTRATE         0x00000002
 182 #define ATH_RC_SHORT_PREAMBLE           0x00000004
 183
 184 struct ath_rc_series {
 185         u8    rix;
 186         u8    tries;
 187         u8    flags;
 188         u32   max_4ms_framelen;
 189 };
 190
 191 /* rcs_flags definition */
 192 #define ATH_RC_DS_FLAG               0x01
 193 #define ATH_RC_CW40_FLAG             0x02    /* CW 40 */
 194 #define ATH_RC_SGI_FLAG              0x04    /* Short Guard Interval */
 195 #define ATH_RC_HT_FLAG               0x08    /* HT */
 196 #define ATH_RC_RTSCTS_FLAG           0x10    /* RTS-CTS */
 197
 198 /*
 199  * State structures for new rate adaptation code
 200  */
 201 #define MAX_TX_RATE_TBL         64
 202 #define MAX_TX_RATE_PHY         48
 203
 204 struct ath_tx_ratectrl_state {
 205         int8_t rssi_thres; /* required rssi for this rate (dB) */
 206         u8 per; /* recent estimate of packet error rate (%) */
 207 };
 208
 209 struct ath_tx_ratectrl {
 210         struct ath_tx_ratectrl_state state[MAX_TX_RATE_TBL]; /* state */
 211         int8_t rssi_last;            /* last ack rssi */
 212         int8_t rssi_last_lookup;        /* last ack rssi used for lookup */
 213         int8_t rssi_last_prev;  /* previous last ack rssi */
 214         int8_t rssi_last_prev2; /* 2nd previous last ack rssi */
 215         int32_t rssi_sum_cnt;        /* count of rssi_sum for averaging */
 216         int32_t rssi_sum_rate;       /* rate that we are averaging */
 217         int32_t rssi_sum;           /* running sum of rssi for averaging */
 218         u32 valid_txrate_mask;   /* mask of valid rates */
 219         u8 rate_table_size;      /* rate table size */
 220         u8 rate_max;            /* max rate that has recently worked */
 221         u8 probe_rate;          /* rate we are probing at */
 222         u32 rssi_time;          /* msec timestamp for last ack rssi */
 223         u32 rssi_down_time;      /* msec timestamp for last down step */
 224         u32 probe_time;         /* msec timestamp for last probe */
 225         u8 hw_maxretry_pktcnt;   /* num packets since we got
 226                                         HW max retry error */
 227         u8 max_valid_rate;       /* maximum number of valid rate */
 228         u8 valid_rate_index[MAX_TX_RATE_TBL]; /* valid rate index */
 229         u32 per_down_time;       /* msec timstamp for last
 230                                         PER down step */
 231
 232         /* 11n state */
 233         u8  valid_phy_ratecnt[WLAN_RC_PHY_MAX]; /* valid rate count */
 234         u8  valid_phy_rateidx[WLAN_RC_PHY_MAX][MAX_TX_RATE_TBL];
 235         u8  rc_phy_mode;
 236         u8  rate_max_phy;        /* Phy index for the max rate */
 237         u32 rate_max_lastused;   /* msec timstamp of when we
 238                                         last used rateMaxPhy */
 239         u32 probe_interval;     /* interval for ratectrl to probe
 240                                         for other rates */
 241 };
 242
 243 struct ath_rateset {
 244         u8 rs_nrates;
 245         u8 rs_rates[ATH_RATE_MAX];
 246 };
 247
 248 /* per-device state */
 249 struct ath_rate_softc {
 250         /* phy tables that contain rate control data */
 251         const void *hw_rate_table[WIRELESS_MODE_MAX];
 252         int fixedrix;   /* -1 or index of fixed rate */
 253 };
 254
 255 /* per-node state */
 256 struct ath_rate_node {
 257         struct ath_tx_ratectrl tx_ratectrl;     /* rate control state proper */
 258         u32 prev_data_rix;      /* rate idx of last data frame */
 259
 260         /* map of rate ix -> negotiated rate set ix */
 261         u8 rixmap[MAX_TX_RATE_TBL];
 262
 263         /* map of ht rate ix -> negotiated rate set ix */
 264         u8 ht_rixmap[MAX_TX_RATE_TBL];
 265
 266         u8 ht_cap;              /* ht capabilities */
 267         u8 ant_tx;              /* current transmit antenna */
 268
 269         u8 single_stream;   /* When TRUE, only single
 270                                 stream Tx possible */
 271         struct ath_rateset neg_rates;   /* Negotiated rates */
 272         struct ath_rateset neg_ht_rates;        /* Negotiated HT rates */
 273         struct ath_rate_softc *asc; /* back pointer to atheros softc */
 274         struct ath_vap *avp;    /* back pointer to vap */
 275 };
 276
 277 /* Driver data of ieee80211_tx_info */
 278 struct ath_tx_info_priv {
 279         struct ath_rc_series rcs[4];
 280         struct ath_tx_status tx;
 281         int n_frames;
 282         int n_bad_frames;
 283         u8 min_rate;
 284 };
 285
 286 /*
 287  * Attach/detach a rate control module.
 288  */
 289 struct ath_rate_softc *ath_rate_attach(struct ath_hal *ah);
 290 void ath_rate_detach(struct ath_rate_softc *asc);
 291
 292 /*
 293  * Update/reset rate control state for 802.11 state transitions.
 294  * Important mostly as the analog to ath_rate_newassoc when operating
 295  * in station mode.
 296  */
 297 void ath_rc_node_update(struct ieee80211_hw *hw, struct ath_rate_node *rc_priv);
 298 void ath_rate_newstate(struct ath_softc *sc, struct ath_vap *avp);
 299
 300 /*
 301  * Return the tx rate series.
 302  */
 303 void ath_rate_findrate(struct ath_softc *sc, struct ath_rate_node *ath_rc_priv,
 304                        int num_tries, int num_rates,
 305                        unsigned int rcflag, struct ath_rc_series[],
 306                        int *is_probe, int isretry);
 307 /*
 308  * Return rate index for given Dot11 Rate.
 309  */
 310 u8 ath_rate_findrateix(struct ath_softc *sc,
 311                              u8 dot11_rate);
 312
 313 /* Routines to register/unregister rate control algorithm */
 314 int ath_rate_control_register(void);
 315 void ath_rate_control_unregister(void);
 316
 317 #endif /* RC_H */