drivers/net/wireless/rsi/rsi_91x_core.c

   1 /**
   2  * Copyright (c) 2014 Redpine Signals Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include "rsi_mgmt.h"
  18 #include "rsi_common.h"
  19
  20 /**
  21  * rsi_determine_min_weight_queue() - This function determines the queue with
  22  *                                    the min weight.
  23  * @common: Pointer to the driver private structure.
  24  *
  25  * Return: q_num: Corresponding queue number.
  26  */
  27 static u8 rsi_determine_min_weight_queue(struct rsi_common *common)
  28 {
  29         struct wmm_qinfo *tx_qinfo = common->tx_qinfo;
  30         u32 q_len = 0;
  31         u8 ii = 0;
  32
  33         for (ii = 0; ii < NUM_EDCA_QUEUES; ii++) {
  34                 q_len = skb_queue_len(&common->tx_queue[ii]);
  35                 if ((tx_qinfo[ii].pkt_contended) && q_len) {
  36                         common->min_weight = tx_qinfo[ii].weight;
  37                         break;
  38                 }
  39         }
  40         return ii;
  41 }
  42
  43 /**
  44  * rsi_recalculate_weights() - This function recalculates the weights
  45  *                             corresponding to each queue.
  46  * @common: Pointer to the driver private structure.
  47  *
  48  * Return: recontend_queue bool variable
  49  */
  50 static bool rsi_recalculate_weights(struct rsi_common *common)
  51 {
  52         struct wmm_qinfo *tx_qinfo = common->tx_qinfo;
  53         bool recontend_queue = false;
  54         u8 ii = 0;
  55         u32 q_len = 0;
  56
  57         for (ii = 0; ii < NUM_EDCA_QUEUES; ii++) {
  58                 q_len = skb_queue_len(&common->tx_queue[ii]);
  59                 /* Check for the need of contention */
  60                 if (q_len) {
  61                         if (tx_qinfo[ii].pkt_contended) {
  62                                 tx_qinfo[ii].weight =
  63                                 ((tx_qinfo[ii].weight > common->min_weight) ?
  64                                  tx_qinfo[ii].weight - common->min_weight : 0);
  65                         } else {
  66                                 tx_qinfo[ii].pkt_contended = 1;
  67                                 tx_qinfo[ii].weight = tx_qinfo[ii].wme_params;
  68                                 recontend_queue = true;
  69                         }
  70                 } else { /* No packets so no contention */
  71                         tx_qinfo[ii].weight = 0;
  72                         tx_qinfo[ii].pkt_contended = 0;
  73                 }
  74         }
  75
  76         return recontend_queue;
  77 }
  78
  79 /**
  80  * rsi_core_determine_hal_queue() - This function determines the queue from
  81  *                                  which packet has to be dequeued.
  82  * @common: Pointer to the driver private structure.
  83  *
  84  * Return: q_num: Corresponding queue number on success.
  85  */
  86 static u8 rsi_core_determine_hal_queue(struct rsi_common *common)
  87 {
  88         bool recontend_queue = false;
  89         u32 q_len = 0;
  90         u8 q_num = INVALID_QUEUE;
  91         u8 ii = 0, min = 0;
  92
  93         if (skb_queue_len(&common->tx_queue[MGMT_SOFT_Q])) {
  94                 if (!common->mgmt_q_block)
  95                         q_num = MGMT_SOFT_Q;
  96                 return q_num;
  97         }
  98
  99         if (common->pkt_cnt != 0) {
 100                 --common->pkt_cnt;
 101                 return common->selected_qnum;
 102         }
 103
 104 get_queue_num:
 105         recontend_queue = false;
 106
 107         q_num = rsi_determine_min_weight_queue(common);
 108
 109         q_len = skb_queue_len(&common->tx_queue[ii]);
 110         ii = q_num;
 111
 112         /* Selecting the queue with least back off */
 113         for (; ii < NUM_EDCA_QUEUES; ii++) {
 114                 if (((common->tx_qinfo[ii].pkt_contended) &&
 115                      (common->tx_qinfo[ii].weight < min)) && q_len) {
 116                         min = common->tx_qinfo[ii].weight;
 117                         q_num = ii;
 118                 }
 119         }
 120
 121         if (q_num < NUM_EDCA_QUEUES)
 122                 common->tx_qinfo[q_num].pkt_contended = 0;
 123
 124         /* Adjust the back off values for all queues again */
 125         recontend_queue = rsi_recalculate_weights(common);
 126
 127         q_len = skb_queue_len(&common->tx_queue[q_num]);
 128         if (!q_len) {
 129                 /* If any queues are freshly contended and the selected queue
 130                  * doesn't have any packets
 131                  * then get the queue number again with fresh values
 132                  */
 133                 if (recontend_queue)
 134                         goto get_queue_num;
 135
 136                 q_num = INVALID_QUEUE;
 137                 return q_num;
 138         }
 139
 140         common->selected_qnum = q_num;
 141         q_len = skb_queue_len(&common->tx_queue[q_num]);
 142
 143         switch (common->selected_qnum) {
 144         case VO_Q:
 145                 if (q_len > MAX_CONTINUOUS_VO_PKTS)
 146                         common->pkt_cnt = (MAX_CONTINUOUS_VO_PKTS - 1);
 147                 else
 148                         common->pkt_cnt = --q_len;
 149                 break;
 150
 151         case VI_Q:
 152                 if (q_len > MAX_CONTINUOUS_VI_PKTS)
 153                         common->pkt_cnt = (MAX_CONTINUOUS_VI_PKTS - 1);
 154                 else
 155                         common->pkt_cnt = --q_len;
 156
 157                 break;
 158
 159         default:
 160                 common->pkt_cnt = 0;
 161                 break;
 162         }
 163
 164         return q_num;
 165 }
 166
 167 /**
 168  * rsi_core_queue_pkt() - This functions enqueues the packet to the queue
 169  *                        specified by the queue number.
 170  * @common: Pointer to the driver private structure.
 171  * @skb: Pointer to the socket buffer structure.
 172  *
 173  * Return: None.
 174  */
 175 static void rsi_core_queue_pkt(struct rsi_common *common,
 176                                struct sk_buff *skb)
 177 {
 178         u8 q_num = skb->priority;
 179         if (q_num >= NUM_SOFT_QUEUES) {
 180                 rsi_dbg(ERR_ZONE, "%s: Invalid Queue Number: q_num = %d\n",
 181                         __func__, q_num);
 182                 dev_kfree_skb(skb);
 183                 return;
 184         }
 185
 186         skb_queue_tail(&common->tx_queue[q_num], skb);
 187 }
 188
 189 /**
 190  * rsi_core_dequeue_pkt() - This functions dequeues the packet from the queue
 191  *                          specified by the queue number.
 192  * @common: Pointer to the driver private structure.
 193  * @q_num: Queue number.
 194  *
 195  * Return: Pointer to sk_buff structure.
 196  */
 197 static struct sk_buff *rsi_core_dequeue_pkt(struct rsi_common *common,
 198                                             u8 q_num)
 199 {
 200         if (q_num >= NUM_SOFT_QUEUES) {
 201                 rsi_dbg(ERR_ZONE, "%s: Invalid Queue Number: q_num = %d\n",
 202                         __func__, q_num);
 203                 return NULL;
 204         }
 205
 206         return skb_dequeue(&common->tx_queue[q_num]);
 207 }
 208
 209 /**
 210  * rsi_core_qos_processor() - This function is used to determine the wmm queue
 211  *                            based on the backoff procedure. Data packets are
 212  *                            dequeued from the selected hal queue and sent to
 213  *                            the below layers.
 214  * @common: Pointer to the driver private structure.
 215  *
 216  * Return: None.
 217  */
 218 void rsi_core_qos_processor(struct rsi_common *common)
 219 {
 220         struct rsi_hw *adapter = common->priv;
 221         struct sk_buff *skb;
 222         unsigned long tstamp_1, tstamp_2;
 223         u8 q_num;
 224         int status;
 225
 226         tstamp_1 = jiffies;
 227         while (1) {
 228                 q_num = rsi_core_determine_hal_queue(common);
 229                 rsi_dbg(DATA_TX_ZONE,
 230                         "%s: Queue number = %d\n", __func__, q_num);
 231
 232                 if (q_num == INVALID_QUEUE) {
 233                         rsi_dbg(DATA_TX_ZONE, "%s: No More Pkt\n", __func__);
 234                         break;
 235                 }
 236
 237                 mutex_lock(&common->tx_rxlock);
 238
 239                 status = adapter->check_hw_queue_status(adapter, q_num);
 240                 if ((status <= 0)) {
 241                         mutex_unlock(&common->tx_rxlock);
 242                         break;
 243                 }
 244
 245                 if ((q_num < MGMT_SOFT_Q) &&
 246                     ((skb_queue_len(&common->tx_queue[q_num])) <=
 247                       MIN_DATA_QUEUE_WATER_MARK)) {
 248                         if (ieee80211_queue_stopped(adapter->hw, WME_AC(q_num)))
 249                                 ieee80211_wake_queue(adapter->hw,
 250                                                      WME_AC(q_num));
 251                 }
 252
 253                 skb = rsi_core_dequeue_pkt(common, q_num);
 254                 if (skb == NULL) {
 255                         mutex_unlock(&common->tx_rxlock);
 256                         break;
 257                 }
 258
 259                 if (q_num == MGMT_SOFT_Q)
 260                         status = rsi_send_mgmt_pkt(common, skb);
 261                 else
 262                         status = rsi_send_data_pkt(common, skb);
 263
 264                 if (status) {
 265                         mutex_unlock(&common->tx_rxlock);
 266                         break;
 267                 }
 268
 269                 common->tx_stats.total_tx_pkt_send[q_num]++;
 270
 271                 tstamp_2 = jiffies;
 272                 mutex_unlock(&common->tx_rxlock);
 273
 274                 if (tstamp_2 > tstamp_1 + (300 * HZ / 1000))
 275                         schedule();
 276         }
 277 }
 278
 279 /**
 280  * rsi_core_xmit() - This function transmits the packets received from mac80211
 281  * @common: Pointer to the driver private structure.
 282  * @skb: Pointer to the socket buffer structure.
 283  *
 284  * Return: None.
 285  */
 286 void rsi_core_xmit(struct rsi_common *common, struct sk_buff *skb)
 287 {
 288         struct rsi_hw *adapter = common->priv;
 289         struct ieee80211_tx_info *info;
 290         struct skb_info *tx_params;
 291         struct ieee80211_hdr *tmp_hdr = NULL;
 292         u8 q_num, tid = 0;
 293
 294         if ((!skb) || (!skb->len)) {
 295                 rsi_dbg(ERR_ZONE, "%s: Null skb/zero Length packet\n",
 296                         __func__);
 297                 goto xmit_fail;
 298         }
 299         info = IEEE80211_SKB_CB(skb);
 300         tx_params = (struct skb_info *)info->driver_data;
 301         tmp_hdr = (struct ieee80211_hdr *)&skb->data[0];
 302
 303         if (common->fsm_state != FSM_MAC_INIT_DONE) {
 304                 rsi_dbg(ERR_ZONE, "%s: FSM state not open\n", __func__);
 305                 goto xmit_fail;
 306         }
 307
 308         if ((ieee80211_is_mgmt(tmp_hdr->frame_control)) ||
 309             (ieee80211_is_ctl(tmp_hdr->frame_control))) {
 310                 q_num = MGMT_SOFT_Q;
 311                 skb->priority = q_num;
 312         } else {
 313                 if (ieee80211_is_data_qos(tmp_hdr->frame_control)) {
 314                         tid = (skb->data[24] & IEEE80211_QOS_TID);
 315                         skb->priority = TID_TO_WME_AC(tid);
 316                 } else {
 317                         tid = IEEE80211_NONQOS_TID;
 318                         skb->priority = BE_Q;
 319                 }
 320                 q_num = skb->priority;
 321                 tx_params->tid = tid;
 322                 tx_params->sta_id = 0;
 323         }
 324
 325         if ((q_num != MGMT_SOFT_Q) &&
 326             ((skb_queue_len(&common->tx_queue[q_num]) + 1) >=
 327              DATA_QUEUE_WATER_MARK)) {
 328                 if (!ieee80211_queue_stopped(adapter->hw, WME_AC(q_num)))
 329                         ieee80211_stop_queue(adapter->hw, WME_AC(q_num));
 330                 rsi_set_event(&common->tx_thread.event);
 331                 goto xmit_fail;
 332         }
 333
 334         rsi_core_queue_pkt(common, skb);
 335         rsi_dbg(DATA_TX_ZONE, "%s: ===> Scheduling TX thead <===\n", __func__);
 336         rsi_set_event(&common->tx_thread.event);
 337
 338         return;
 339
 340 xmit_fail:
 341         rsi_dbg(ERR_ZONE, "%s: Failed to queue packet\n", __func__);
 342         /* Dropping pkt here */
 343         ieee80211_free_txskb(common->priv->hw, skb);
 344 }