drivers/net/wireless/rtlwifi/rc.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2009-2010  Realtek Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  * wlanfae <wlanfae@realtek.com>
  23  * Realtek Corporation, No. 2, Innovation Road II, Hsinchu Science Park,
  24  * Hsinchu 300, Taiwan.
  25  *
  26  * Larry Finger <Larry.Finger@lwfinger.net>
  27  *
  28  *****************************************************************************/
  29
  30 #include "wifi.h"
  31 #include "base.h"
  32 #include "rc.h"
  33
  34 /*
  35  *Finds the highest rate index we can use
  36  *if skb is special data like DHCP/EAPOL, we set should
  37  *it to lowest rate CCK_1M, otherwise we set rate to
  38  *CCK11M or OFDM_54M based on wireless mode.
  39  */
  40 static u8 _rtl_rc_get_highest_rix(struct rtl_priv *rtlpriv,
  41                                   struct sk_buff *skb, bool not_data)
  42 {
  43         struct rtl_mac *rtlmac = rtl_mac(rtlpriv);
  44
  45         /*
  46          *mgt use 1M, although we have check it
  47          *before this function use rate_control_send_low,
  48          *we still check it here
  49          */
  50         if (not_data)
  51                 return rtlpriv->cfg->maps[RTL_RC_CCK_RATE1M];
  52
  53         /*
  54          *this rate is no use for true rate, firmware
  55          *will control rate at all it just used for
  56          *1.show in iwconfig in B/G mode
  57          *2.in rtl_get_tcb_desc when we check rate is
  58          *      1M we will not use FW rate but user rate.
  59          */
  60         if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true)) {
  61                 return rtlpriv->cfg->maps[RTL_RC_CCK_RATE1M];
  62         } else {
  63                 if (rtlmac->mode == WIRELESS_MODE_B)
  64                         return rtlpriv->cfg->maps[RTL_RC_CCK_RATE11M];
  65                 else
  66                         return rtlpriv->cfg->maps[RTL_RC_OFDM_RATE54M];
  67         }
  68 }
  69
  70 static void _rtl_rc_rate_set_series(struct rtl_priv *rtlpriv,
  71                                     struct ieee80211_tx_rate *rate,
  72                                     struct ieee80211_tx_rate_control *txrc,
  73                                     u8 tries, u8 rix, int rtsctsenable,
  74                                     bool not_data)
  75 {
  76         struct rtl_mac *mac = rtl_mac(rtlpriv);
  77
  78         rate->count = tries;
  79         rate->idx = (rix > 0x2) ? rix : 0x2;
  80
  81         if (!not_data) {
  82                 if (txrc->short_preamble)
  83                         rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
  84                 if (mac->bw_40)
  85                         rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
  86                 if (mac->sgi_20 || mac->sgi_40)
  87                         rate->flags |= IEEE80211_TX_RC_SHORT_GI;
  88                 if (mac->ht_enable)
  89                         rate->flags |= IEEE80211_TX_RC_MCS;
  90         }
  91 }
  92
  93 static void rtl_get_rate(void *ppriv, struct ieee80211_sta *sta,
  94                          void *priv_sta, struct ieee80211_tx_rate_control *txrc)
  95 {
  96         struct rtl_priv *rtlpriv = ppriv;
  97         struct sk_buff *skb = txrc->skb;
  98         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
  99         struct ieee80211_tx_rate *rates = tx_info->control.rates;
 100         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 101         __le16 fc = hdr->frame_control;
 102         u8 try_per_rate, i, rix;
 103         bool not_data = !ieee80211_is_data(fc);
 104
 105         if (rate_control_send_low(sta, priv_sta, txrc))
 106                 return;
 107
 108         rix = _rtl_rc_get_highest_rix(rtlpriv, skb, not_data);
 109
 110         try_per_rate = 1;
 111         _rtl_rc_rate_set_series(rtlpriv, &rates[0], txrc,
 112                                 try_per_rate, rix, 1, not_data);
 113
 114         if (!not_data) {
 115                 for (i = 1; i < 4; i++)
 116                         _rtl_rc_rate_set_series(rtlpriv, &rates[i],
 117                                                 txrc, i, (rix - i), 1,
 118                                                 not_data);
 119         }
 120 }
 121
 122 static bool _rtl_tx_aggr_check(struct rtl_priv *rtlpriv, u16 tid)
 123 {
 124         struct rtl_mac *mac = rtl_mac(rtlpriv);
 125
 126         if (mac->act_scanning)
 127                 return false;
 128
 129         if (mac->cnt_after_linked < 3)
 130                 return false;
 131
 132         if (mac->tids[tid].agg.agg_state == RTL_AGG_OFF)
 133                 return true;
 134
 135         return false;
 136 }
 137
 138 /*mac80211 Rate Control callbacks*/
 139 static void rtl_tx_status(void *ppriv,
 140                           struct ieee80211_supported_band *sband,
 141                           struct ieee80211_sta *sta, void *priv_sta,
 142                           struct sk_buff *skb)
 143 {
 144         struct rtl_priv *rtlpriv = ppriv;
 145         struct rtl_mac *mac = rtl_mac(rtlpriv);
 146         struct ieee80211_hdr *hdr;
 147         __le16 fc;
 148
 149         hdr = (struct ieee80211_hdr *)skb->data;
 150         fc = hdr->frame_control;
 151
 152         if (!priv_sta || !ieee80211_is_data(fc))
 153                 return;
 154
 155         if (rtl_is_special_data(mac->hw, skb, true))
 156                 return;
 157
 158         if (is_multicast_ether_addr(ieee80211_get_DA(hdr))
 159             || is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
 160                 return;
 161
 162         /* Check if aggregation has to be enabled for this tid */
 163         if (conf_is_ht(&mac->hw->conf) &&
 164             !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
 165                 if (ieee80211_is_data_qos(fc)) {
 166                         u8 *qc, tid;
 167
 168                         qc = ieee80211_get_qos_ctl(hdr);
 169                         tid = qc[0] & 0xf;
 170
 171                         if (_rtl_tx_aggr_check(rtlpriv, tid))
 172                                 ieee80211_start_tx_ba_session(sta, tid, 5000);
 173                 }
 174         }
 175 }
 176
 177 static void rtl_rate_init(void *ppriv,
 178                           struct ieee80211_supported_band *sband,
 179                           struct ieee80211_sta *sta, void *priv_sta)
 180 {
 181         struct rtl_priv *rtlpriv = ppriv;
 182         struct rtl_mac *mac = rtl_mac(rtlpriv);
 183         u8 is_ht = conf_is_ht(&mac->hw->conf);
 184
 185         if ((mac->opmode == NL80211_IFTYPE_STATION) ||
 186             (mac->opmode == NL80211_IFTYPE_MESH_POINT) ||
 187             (mac->opmode == NL80211_IFTYPE_ADHOC)) {
 188
 189                 switch (sband->band) {
 190                 case IEEE80211_BAND_2GHZ:
 191                         rtlpriv->rate_priv->cur_ratetab_idx =
 192                             RATR_INX_WIRELESS_G;
 193                         if (is_ht)
 194                                 rtlpriv->rate_priv->cur_ratetab_idx =
 195                                     RATR_INX_WIRELESS_NGB;
 196                         break;
 197                 case IEEE80211_BAND_5GHZ:
 198                         rtlpriv->rate_priv->cur_ratetab_idx =
 199                             RATR_INX_WIRELESS_A;
 200                         if (is_ht)
 201                                 rtlpriv->rate_priv->cur_ratetab_idx =
 202                                     RATR_INX_WIRELESS_NGB;
 203                         break;
 204                 default:
 205                         RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING,
 206                                  ("Invalid band\n"));
 207                         rtlpriv->rate_priv->cur_ratetab_idx =
 208                             RATR_INX_WIRELESS_NGB;
 209                         break;
 210                 }
 211
 212                 RT_TRACE(rtlpriv, COMP_RATE, DBG_DMESG,
 213                          ("Choosing rate table index: %d\n",
 214                           rtlpriv->rate_priv->cur_ratetab_idx));
 215
 216         }
 217
 218 }
 219
 220 static void rtl_rate_update(void *ppriv,
 221                             struct ieee80211_supported_band *sband,
 222                             struct ieee80211_sta *sta, void *priv_sta,
 223                             u32 changed,
 224                             enum nl80211_channel_type oper_chan_type)
 225 {
 226         struct rtl_priv *rtlpriv = ppriv;
 227         struct rtl_mac *mac = rtl_mac(rtlpriv);
 228         struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
 229         bool oper_cw40 = false, oper_sgi40;
 230         bool local_cw40 = mac->bw_40;
 231         bool local_sgi40 = mac->sgi_40;
 232         u8 is_ht = conf_is_ht(&mac->hw->conf);
 233
 234         if (changed & IEEE80211_RC_HT_CHANGED) {
 235                 if (mac->opmode != NL80211_IFTYPE_STATION)
 236                         return;
 237
 238                 if (rtlhal->hw->conf.channel_type == NL80211_CHAN_HT40MINUS ||
 239                     rtlhal->hw->conf.channel_type == NL80211_CHAN_HT40PLUS)
 240                         oper_cw40 = true;
 241
 242                 oper_sgi40 = mac->sgi_40;
 243
 244                 if ((local_cw40 != oper_cw40) || (local_sgi40 != oper_sgi40)) {
 245                         switch (sband->band) {
 246                         case IEEE80211_BAND_2GHZ:
 247                                 rtlpriv->rate_priv->cur_ratetab_idx =
 248                                     RATR_INX_WIRELESS_G;
 249                                 if (is_ht)
 250                                         rtlpriv->rate_priv->cur_ratetab_idx =
 251                                             RATR_INX_WIRELESS_NGB;
 252                                 break;
 253                         case IEEE80211_BAND_5GHZ:
 254                                 rtlpriv->rate_priv->cur_ratetab_idx =
 255                                     RATR_INX_WIRELESS_A;
 256                                 if (is_ht)
 257                                         rtlpriv->rate_priv->cur_ratetab_idx =
 258                                             RATR_INX_WIRELESS_NGB;
 259                                 break;
 260                         default:
 261                                 RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 262                                          ("Invalid band\n"));
 263                                 rtlpriv->rate_priv->cur_ratetab_idx =
 264                                     RATR_INX_WIRELESS_NGB;
 265                                 break;
 266                         }
 267                 }
 268         }
 269 }
 270
 271 static void *rtl_rate_alloc(struct ieee80211_hw *hw,
 272                 struct dentry *debugfsdir)
 273 {
 274         struct rtl_priv *rtlpriv = rtl_priv(hw);
 275         return rtlpriv;
 276 }
 277
 278 static void rtl_rate_free(void *rtlpriv)
 279 {
 280         return;
 281 }
 282
 283 static void *rtl_rate_alloc_sta(void *ppriv,
 284                                 struct ieee80211_sta *sta, gfp_t gfp)
 285 {
 286         struct rtl_priv *rtlpriv = ppriv;
 287         struct rtl_rate_priv *rate_priv;
 288
 289         rate_priv = kzalloc(sizeof(struct rtl_rate_priv), gfp);
 290         if (!rate_priv) {
 291                 RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 292                          ("Unable to allocate private rc structure\n"));
 293                 return NULL;
 294         }
 295
 296         rtlpriv->rate_priv = rate_priv;
 297
 298         return rate_priv;
 299 }
 300
 301 static void rtl_rate_free_sta(void *rtlpriv,
 302                               struct ieee80211_sta *sta, void *priv_sta)
 303 {
 304         struct rtl_rate_priv *rate_priv = priv_sta;
 305         kfree(rate_priv);
 306 }
 307
 308 static struct rate_control_ops rtl_rate_ops = {
 309         .module = NULL,
 310         .name = "rtl_rc",
 311         .alloc = rtl_rate_alloc,
 312         .free = rtl_rate_free,
 313         .alloc_sta = rtl_rate_alloc_sta,
 314         .free_sta = rtl_rate_free_sta,
 315         .rate_init = rtl_rate_init,
 316         .rate_update = rtl_rate_update,
 317         .tx_status = rtl_tx_status,
 318         .get_rate = rtl_get_rate,
 319 };
 320
 321 int rtl_rate_control_register(void)
 322 {
 323         return ieee80211_rate_control_register(&rtl_rate_ops);
 324 }
 325
 326 void rtl_rate_control_unregister(void)
 327 {
 328         ieee80211_rate_control_unregister(&rtl_rate_ops);
 329 }