SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/net/wireless/libertas/rx.c

   1 /**
   2   * This file contains the handling of RX in wlan driver.
   3   */
   4 #include <linux/etherdevice.h>
   5 #include <linux/types.h>
   6
   7 #include "hostcmd.h"
   8 #include "radiotap.h"
   9 #include "decl.h"
  10 #include "dev.h"
  11 #include "wext.h"
  12
  13 struct eth803hdr {
  14         u8 dest_addr[6];
  15         u8 src_addr[6];
  16         u16 h803_len;
  17 } __attribute__ ((packed));
  18
  19 struct rfc1042hdr {
  20         u8 llc_dsap;
  21         u8 llc_ssap;
  22         u8 llc_ctrl;
  23         u8 snap_oui[3];
  24         u16 snap_type;
  25 } __attribute__ ((packed));
  26
  27 struct rxpackethdr {
  28         struct rxpd rx_pd;
  29         struct eth803hdr eth803_hdr;
  30         struct rfc1042hdr rfc1042_hdr;
  31 } __attribute__ ((packed));
  32
  33 struct rx80211packethdr {
  34         struct rxpd rx_pd;
  35         void *eth80211_hdr;
  36 } __attribute__ ((packed));
  37
  38 static int process_rxed_802_11_packet(struct lbs_private *priv,
  39         struct sk_buff *skb);
  40
  41 /**
  42  *  @brief This function computes the avgSNR .
  43  *
  44  *  @param priv    A pointer to struct lbs_private structure
  45  *  @return        avgSNR
  46  */
  47 static u8 lbs_getavgsnr(struct lbs_private *priv)
  48 {
  49         u8 i;
  50         u16 temp = 0;
  51         if (priv->numSNRNF == 0)
  52                 return 0;
  53         for (i = 0; i < priv->numSNRNF; i++)
  54                 temp += priv->rawSNR[i];
  55         return (u8) (temp / priv->numSNRNF);
  56
  57 }
  58
  59 /**
  60  *  @brief This function computes the AvgNF
  61  *
  62  *  @param priv    A pointer to struct lbs_private structure
  63  *  @return        AvgNF
  64  */
  65 static u8 lbs_getavgnf(struct lbs_private *priv)
  66 {
  67         u8 i;
  68         u16 temp = 0;
  69         if (priv->numSNRNF == 0)
  70                 return 0;
  71         for (i = 0; i < priv->numSNRNF; i++)
  72                 temp += priv->rawNF[i];
  73         return (u8) (temp / priv->numSNRNF);
  74
  75 }
  76
  77 /**
  78  *  @brief This function save the raw SNR/NF to our internel buffer
  79  *
  80  *  @param priv    A pointer to struct lbs_private structure
  81  *  @param prxpd   A pointer to rxpd structure of received packet
  82  *  @return        n/a
  83  */
  84 static void lbs_save_rawSNRNF(struct lbs_private *priv, struct rxpd *p_rx_pd)
  85 {
  86         if (priv->numSNRNF < DEFAULT_DATA_AVG_FACTOR)
  87                 priv->numSNRNF++;
  88         priv->rawSNR[priv->nextSNRNF] = p_rx_pd->snr;
  89         priv->rawNF[priv->nextSNRNF] = p_rx_pd->nf;
  90         priv->nextSNRNF++;
  91         if (priv->nextSNRNF >= DEFAULT_DATA_AVG_FACTOR)
  92                 priv->nextSNRNF = 0;
  93         return;
  94 }
  95
  96 /**
  97  *  @brief This function computes the RSSI in received packet.
  98  *
  99  *  @param priv    A pointer to struct lbs_private structure
 100  *  @param prxpd   A pointer to rxpd structure of received packet
 101  *  @return        n/a
 102  */
 103 static void lbs_compute_rssi(struct lbs_private *priv, struct rxpd *p_rx_pd)
 104 {
 105
 106         lbs_deb_enter(LBS_DEB_RX);
 107
 108         lbs_deb_rx("rxpd: SNR %d, NF %d\n", p_rx_pd->snr, p_rx_pd->nf);
 109         lbs_deb_rx("before computing SNR: SNR-avg = %d, NF-avg = %d\n",
 110                priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
 111                priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
 112
 113         priv->SNR[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->snr;
 114         priv->NF[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->nf;
 115         lbs_save_rawSNRNF(priv, p_rx_pd);
 116
 117         priv->SNR[TYPE_RXPD][TYPE_AVG] = lbs_getavgsnr(priv) * AVG_SCALE;
 118         priv->NF[TYPE_RXPD][TYPE_AVG] = lbs_getavgnf(priv) * AVG_SCALE;
 119         lbs_deb_rx("after computing SNR: SNR-avg = %d, NF-avg = %d\n",
 120                priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
 121                priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
 122
 123         priv->RSSI[TYPE_RXPD][TYPE_NOAVG] =
 124             CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_NOAVG],
 125                      priv->NF[TYPE_RXPD][TYPE_NOAVG]);
 126
 127         priv->RSSI[TYPE_RXPD][TYPE_AVG] =
 128             CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
 129                      priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
 130
 131         lbs_deb_leave(LBS_DEB_RX);
 132 }
 133
 134 void lbs_upload_rx_packet(struct lbs_private *priv, struct sk_buff *skb)
 135 {
 136         lbs_deb_rx("skb->data %p\n", skb->data);
 137
 138         if (priv->monitormode != LBS_MONITOR_OFF) {
 139                 skb->protocol = eth_type_trans(skb, priv->rtap_net_dev);
 140         } else {
 141                 if (priv->mesh_dev && IS_MESH_FRAME(skb))
 142                         skb->protocol = eth_type_trans(skb, priv->mesh_dev);
 143                 else
 144                         skb->protocol = eth_type_trans(skb, priv->dev);
 145         }
 146         skb->ip_summed = CHECKSUM_NONE;
 147         netif_rx(skb);
 148 }
 149
 150 /**
 151  *  @brief This function processes received packet and forwards it
 152  *  to kernel/upper layer
 153  *
 154  *  @param priv    A pointer to struct lbs_private
 155  *  @param skb     A pointer to skb which includes the received packet
 156  *  @return        0 or -1
 157  */
 158 int lbs_process_rxed_packet(struct lbs_private *priv, struct sk_buff *skb)
 159 {
 160         int ret = 0;
 161
 162         struct rxpackethdr *p_rx_pkt;
 163         struct rxpd *p_rx_pd;
 164
 165         int hdrchop;
 166         struct ethhdr *p_ethhdr;
 167
 168         const u8 rfc1042_eth_hdr[] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 169
 170         lbs_deb_enter(LBS_DEB_RX);
 171
 172         if (priv->monitormode != LBS_MONITOR_OFF)
 173                 return process_rxed_802_11_packet(priv, skb);
 174
 175         p_rx_pkt = (struct rxpackethdr *) skb->data;
 176         p_rx_pd = &p_rx_pkt->rx_pd;
 177         if (p_rx_pd->rx_control & RxPD_MESH_FRAME)
 178                 SET_MESH_FRAME(skb);
 179         else
 180                 UNSET_MESH_FRAME(skb);
 181
 182         lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data,
 183                  min_t(unsigned int, skb->len, 100));
 184
 185         if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
 186                 lbs_deb_rx("rx err: frame received with bad length\n");
 187                 priv->stats.rx_length_errors++;
 188                 ret = 0;
 189                 goto done;
 190         }
 191
 192         /*
 193          * Check rxpd status and update 802.3 stat,
 194          */
 195         if (!(p_rx_pd->status & cpu_to_le16(MRVDRV_RXPD_STATUS_OK))) {
 196                 lbs_deb_rx("rx err: frame received with bad status\n");
 197                 lbs_pr_alert("rxpd not ok\n");
 198                 priv->stats.rx_errors++;
 199                 ret = 0;
 200                 goto done;
 201         }
 202
 203         lbs_deb_rx("rx data: skb->len-sizeof(RxPd) = %d-%zd = %zd\n",
 204                skb->len, sizeof(struct rxpd), skb->len - sizeof(struct rxpd));
 205
 206         lbs_deb_hex(LBS_DEB_RX, "RX Data: Dest", p_rx_pkt->eth803_hdr.dest_addr,
 207                 sizeof(p_rx_pkt->eth803_hdr.dest_addr));
 208         lbs_deb_hex(LBS_DEB_RX, "RX Data: Src", p_rx_pkt->eth803_hdr.src_addr,
 209                 sizeof(p_rx_pkt->eth803_hdr.src_addr));
 210
 211         if (memcmp(&p_rx_pkt->rfc1042_hdr,
 212                    rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr)) == 0) {
 213                 /*
 214                  *  Replace the 803 header and rfc1042 header (llc/snap) with an
 215                  *    EthernetII header, keep the src/dst and snap_type (ethertype)
 216                  *
 217                  *  The firmware only passes up SNAP frames converting
 218                  *    all RX Data from 802.11 to 802.2/LLC/SNAP frames.
 219                  *
 220                  *  To create the Ethernet II, just move the src, dst address right
 221                  *    before the snap_type.
 222                  */
 223                 p_ethhdr = (struct ethhdr *)
 224                     ((u8 *) & p_rx_pkt->eth803_hdr
 225                      + sizeof(p_rx_pkt->eth803_hdr) + sizeof(p_rx_pkt->rfc1042_hdr)
 226                      - sizeof(p_rx_pkt->eth803_hdr.dest_addr)
 227                      - sizeof(p_rx_pkt->eth803_hdr.src_addr)
 228                      - sizeof(p_rx_pkt->rfc1042_hdr.snap_type));
 229
 230                 memcpy(p_ethhdr->h_source, p_rx_pkt->eth803_hdr.src_addr,
 231                        sizeof(p_ethhdr->h_source));
 232                 memcpy(p_ethhdr->h_dest, p_rx_pkt->eth803_hdr.dest_addr,
 233                        sizeof(p_ethhdr->h_dest));
 234
 235                 /* Chop off the rxpd + the excess memory from the 802.2/llc/snap header
 236                  *   that was removed
 237                  */
 238                 hdrchop = (u8 *) p_ethhdr - (u8 *) p_rx_pkt;
 239         } else {
 240                 lbs_deb_hex(LBS_DEB_RX, "RX Data: LLC/SNAP",
 241                         (u8 *) & p_rx_pkt->rfc1042_hdr,
 242                         sizeof(p_rx_pkt->rfc1042_hdr));
 243
 244                 /* Chop off the rxpd */
 245                 hdrchop = (u8 *) & p_rx_pkt->eth803_hdr - (u8 *) p_rx_pkt;
 246         }
 247
 248         /* Chop off the leading header bytes so the skb points to the start of
 249          *   either the reconstructed EthII frame or the 802.2/llc/snap frame
 250          */
 251         skb_pull(skb, hdrchop);
 252
 253         /* Take the data rate from the rxpd structure
 254          * only if the rate is auto
 255          */
 256         if (priv->auto_rate)
 257                 priv->cur_rate = lbs_fw_index_to_data_rate(p_rx_pd->rx_rate);
 258
 259         lbs_compute_rssi(priv, p_rx_pd);
 260
 261         lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
 262         priv->stats.rx_bytes += skb->len;
 263         priv->stats.rx_packets++;
 264
 265         lbs_upload_rx_packet(priv, skb);
 266
 267         ret = 0;
 268 done:
 269         lbs_deb_leave_args(LBS_DEB_RX, "ret %d", ret);
 270         return ret;
 271 }
 272 EXPORT_SYMBOL_GPL(lbs_process_rxed_packet);
 273
 274 /**
 275  *  @brief This function converts Tx/Rx rates from the Marvell WLAN format
 276  *  (see Table 2 in Section 3.1) to IEEE80211_RADIOTAP_RATE units (500 Kb/s)
 277  *
 278  *  @param rate    Input rate
 279  *  @return        Output Rate (0 if invalid)
 280  */
 281 static u8 convert_mv_rate_to_radiotap(u8 rate)
 282 {
 283         switch (rate) {
 284         case 0:         /*   1 Mbps */
 285                 return 2;
 286         case 1:         /*   2 Mbps */
 287                 return 4;
 288         case 2:         /* 5.5 Mbps */
 289                 return 11;
 290         case 3:         /*  11 Mbps */
 291                 return 22;
 292         /* case 4: reserved */
 293         case 5:         /*   6 Mbps */
 294                 return 12;
 295         case 6:         /*   9 Mbps */
 296                 return 18;
 297         case 7:         /*  12 Mbps */
 298                 return 24;
 299         case 8:         /*  18 Mbps */
 300                 return 36;
 301         case 9:         /*  24 Mbps */
 302                 return 48;
 303         case 10:                /*  36 Mbps */
 304                 return 72;
 305         case 11:                /*  48 Mbps */
 306                 return 96;
 307         case 12:                /*  54 Mbps */
 308                 return 108;
 309         }
 310         lbs_pr_alert("Invalid Marvell WLAN rate %i\n", rate);
 311         return 0;
 312 }
 313
 314 /**
 315  *  @brief This function processes a received 802.11 packet and forwards it
 316  *  to kernel/upper layer
 317  *
 318  *  @param priv    A pointer to struct lbs_private
 319  *  @param skb     A pointer to skb which includes the received packet
 320  *  @return        0 or -1
 321  */
 322 static int process_rxed_802_11_packet(struct lbs_private *priv,
 323         struct sk_buff *skb)
 324 {
 325         int ret = 0;
 326
 327         struct rx80211packethdr *p_rx_pkt;
 328         struct rxpd *prxpd;
 329         struct rx_radiotap_hdr radiotap_hdr;
 330         struct rx_radiotap_hdr *pradiotap_hdr;
 331
 332         lbs_deb_enter(LBS_DEB_RX);
 333
 334         p_rx_pkt = (struct rx80211packethdr *) skb->data;
 335         prxpd = &p_rx_pkt->rx_pd;
 336
 337         // lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data, min(skb->len, 100));
 338
 339         if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
 340                 lbs_deb_rx("rx err: frame received wit bad length\n");
 341                 priv->stats.rx_length_errors++;
 342                 ret = 0;
 343                 goto done;
 344         }
 345
 346         /*
 347          * Check rxpd status and update 802.3 stat,
 348          */
 349         if (!(prxpd->status & cpu_to_le16(MRVDRV_RXPD_STATUS_OK))) {
 350                 //lbs_deb_rx("rx err: frame received with bad status\n");
 351                 priv->stats.rx_errors++;
 352         }
 353
 354         lbs_deb_rx("rx data: skb->len-sizeof(RxPd) = %d-%zd = %zd\n",
 355                skb->len, sizeof(struct rxpd), skb->len - sizeof(struct rxpd));
 356
 357         /* create the exported radio header */
 358         if (priv->monitormode == LBS_MONITOR_OFF) {
 359                 /* no radio header */
 360                 /* chop the rxpd */
 361                 skb_pull(skb, sizeof(struct rxpd));
 362         }
 363
 364         else {
 365                 /* radiotap header */
 366                 radiotap_hdr.hdr.it_version = 0;
 367                 /* XXX must check this value for pad */
 368                 radiotap_hdr.hdr.it_pad = 0;
 369                 radiotap_hdr.hdr.it_len = cpu_to_le16 (sizeof(struct rx_radiotap_hdr));
 370                 radiotap_hdr.hdr.it_present = cpu_to_le32 (RX_RADIOTAP_PRESENT);
 371                 /* unknown values */
 372                 radiotap_hdr.flags = 0;
 373                 radiotap_hdr.chan_freq = 0;
 374                 radiotap_hdr.chan_flags = 0;
 375                 radiotap_hdr.antenna = 0;
 376                 /* known values */
 377                 radiotap_hdr.rate = convert_mv_rate_to_radiotap(prxpd->rx_rate);
 378                 /* XXX must check no carryout */
 379                 radiotap_hdr.antsignal = prxpd->snr + prxpd->nf;
 380                 radiotap_hdr.rx_flags = 0;
 381                 if (!(prxpd->status & cpu_to_le16(MRVDRV_RXPD_STATUS_OK)))
 382                         radiotap_hdr.rx_flags |= IEEE80211_RADIOTAP_F_RX_BADFCS;
 383                 //memset(radiotap_hdr.pad, 0x11, IEEE80211_RADIOTAP_HDRLEN - 18);
 384
 385                 /* chop the rxpd */
 386                 skb_pull(skb, sizeof(struct rxpd));
 387
 388                 /* add space for the new radio header */
 389                 if ((skb_headroom(skb) < sizeof(struct rx_radiotap_hdr)) &&
 390                     pskb_expand_head(skb, sizeof(struct rx_radiotap_hdr), 0,
 391                                      GFP_ATOMIC)) {
 392                         lbs_pr_alert("%s: couldn't pskb_expand_head\n",
 393                                __func__);
 394                 }
 395
 396                 pradiotap_hdr =
 397                     (struct rx_radiotap_hdr *)skb_push(skb,
 398                                                      sizeof(struct
 399                                                             rx_radiotap_hdr));
 400                 memcpy(pradiotap_hdr, &radiotap_hdr,
 401                        sizeof(struct rx_radiotap_hdr));
 402         }
 403
 404         /* Take the data rate from the rxpd structure
 405          * only if the rate is auto
 406          */
 407         if (priv->auto_rate)
 408                 priv->cur_rate = lbs_fw_index_to_data_rate(prxpd->rx_rate);
 409
 410         lbs_compute_rssi(priv, prxpd);
 411
 412         lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
 413         priv->stats.rx_bytes += skb->len;
 414         priv->stats.rx_packets++;
 415
 416         lbs_upload_rx_packet(priv, skb);
 417
 418         ret = 0;
 419
 420 done:
 421         lbs_deb_leave_args(LBS_DEB_RX, "ret %d", ret);
 422         return ret;
 423 }