2 * This file contains the handling of RX in wlan driver.
4 #include <linux/etherdevice.h>
5 #include <linux/slab.h>
6 #include <linux/types.h>
18 } __attribute__ ((packed));
26 } __attribute__ ((packed));
29 struct eth803hdr eth803_hdr;
30 struct rfc1042hdr rfc1042_hdr;
31 } __attribute__ ((packed));
33 struct rx80211packethdr {
36 } __attribute__ ((packed));
38 static int process_rxed_802_11_packet(struct lbs_private *priv,
42 * @brief This function computes the avgSNR .
44 * @param priv A pointer to struct lbs_private structure
47 static u8 lbs_getavgsnr(struct lbs_private *priv)
51 if (priv->numSNRNF == 0)
53 for (i = 0; i < priv->numSNRNF; i++)
54 temp += priv->rawSNR[i];
55 return (u8) (temp / priv->numSNRNF);
60 * @brief This function computes the AvgNF
62 * @param priv A pointer to struct lbs_private structure
65 static u8 lbs_getavgnf(struct lbs_private *priv)
69 if (priv->numSNRNF == 0)
71 for (i = 0; i < priv->numSNRNF; i++)
72 temp += priv->rawNF[i];
73 return (u8) (temp / priv->numSNRNF);
78 * @brief This function save the raw SNR/NF to our internel buffer
80 * @param priv A pointer to struct lbs_private structure
81 * @param prxpd A pointer to rxpd structure of received packet
84 static void lbs_save_rawSNRNF(struct lbs_private *priv, struct rxpd *p_rx_pd)
86 if (priv->numSNRNF < DEFAULT_DATA_AVG_FACTOR)
88 priv->rawSNR[priv->nextSNRNF] = p_rx_pd->snr;
89 priv->rawNF[priv->nextSNRNF] = p_rx_pd->nf;
91 if (priv->nextSNRNF >= DEFAULT_DATA_AVG_FACTOR)
96 * @brief This function computes the RSSI in received packet.
98 * @param priv A pointer to struct lbs_private structure
99 * @param prxpd A pointer to rxpd structure of received packet
102 static void lbs_compute_rssi(struct lbs_private *priv, struct rxpd *p_rx_pd)
105 lbs_deb_enter(LBS_DEB_RX);
107 lbs_deb_rx("rxpd: SNR %d, NF %d\n", p_rx_pd->snr, p_rx_pd->nf);
108 lbs_deb_rx("before computing SNR: SNR-avg = %d, NF-avg = %d\n",
109 priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
110 priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
112 priv->SNR[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->snr;
113 priv->NF[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->nf;
114 lbs_save_rawSNRNF(priv, p_rx_pd);
116 priv->SNR[TYPE_RXPD][TYPE_AVG] = lbs_getavgsnr(priv) * AVG_SCALE;
117 priv->NF[TYPE_RXPD][TYPE_AVG] = lbs_getavgnf(priv) * AVG_SCALE;
118 lbs_deb_rx("after computing SNR: SNR-avg = %d, NF-avg = %d\n",
119 priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
120 priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
122 priv->RSSI[TYPE_RXPD][TYPE_NOAVG] =
123 CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_NOAVG],
124 priv->NF[TYPE_RXPD][TYPE_NOAVG]);
126 priv->RSSI[TYPE_RXPD][TYPE_AVG] =
127 CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
128 priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
130 lbs_deb_leave(LBS_DEB_RX);
134 * @brief This function processes received packet and forwards it
135 * to kernel/upper layer
137 * @param priv A pointer to struct lbs_private
138 * @param skb A pointer to skb which includes the received packet
141 int lbs_process_rxed_packet(struct lbs_private *priv, struct sk_buff *skb)
144 struct net_device *dev = priv->dev;
145 struct rxpackethdr *p_rx_pkt;
146 struct rxpd *p_rx_pd;
148 struct ethhdr *p_ethhdr;
149 const u8 rfc1042_eth_hdr[] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
151 lbs_deb_enter(LBS_DEB_RX);
155 skb->ip_summed = CHECKSUM_NONE;
157 if (priv->monitormode)
158 return process_rxed_802_11_packet(priv, skb);
160 p_rx_pd = (struct rxpd *) skb->data;
161 p_rx_pkt = (struct rxpackethdr *) ((u8 *)p_rx_pd +
162 le32_to_cpu(p_rx_pd->pkt_ptr));
164 dev = lbs_mesh_set_dev(priv, dev, p_rx_pd);
166 lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data,
167 min_t(unsigned int, skb->len, 100));
169 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
170 lbs_deb_rx("rx err: frame received with bad length\n");
171 dev->stats.rx_length_errors++;
177 lbs_deb_rx("rx data: skb->len - pkt_ptr = %d-%zd = %zd\n",
178 skb->len, (size_t)le32_to_cpu(p_rx_pd->pkt_ptr),
179 skb->len - (size_t)le32_to_cpu(p_rx_pd->pkt_ptr));
181 lbs_deb_hex(LBS_DEB_RX, "RX Data: Dest", p_rx_pkt->eth803_hdr.dest_addr,
182 sizeof(p_rx_pkt->eth803_hdr.dest_addr));
183 lbs_deb_hex(LBS_DEB_RX, "RX Data: Src", p_rx_pkt->eth803_hdr.src_addr,
184 sizeof(p_rx_pkt->eth803_hdr.src_addr));
186 if (memcmp(&p_rx_pkt->rfc1042_hdr,
187 rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr)) == 0) {
189 * Replace the 803 header and rfc1042 header (llc/snap) with an
190 * EthernetII header, keep the src/dst and snap_type (ethertype)
192 * The firmware only passes up SNAP frames converting
193 * all RX Data from 802.11 to 802.2/LLC/SNAP frames.
195 * To create the Ethernet II, just move the src, dst address right
196 * before the snap_type.
198 p_ethhdr = (struct ethhdr *)
199 ((u8 *) &p_rx_pkt->eth803_hdr
200 + sizeof(p_rx_pkt->eth803_hdr) + sizeof(p_rx_pkt->rfc1042_hdr)
201 - sizeof(p_rx_pkt->eth803_hdr.dest_addr)
202 - sizeof(p_rx_pkt->eth803_hdr.src_addr)
203 - sizeof(p_rx_pkt->rfc1042_hdr.snap_type));
205 memcpy(p_ethhdr->h_source, p_rx_pkt->eth803_hdr.src_addr,
206 sizeof(p_ethhdr->h_source));
207 memcpy(p_ethhdr->h_dest, p_rx_pkt->eth803_hdr.dest_addr,
208 sizeof(p_ethhdr->h_dest));
210 /* Chop off the rxpd + the excess memory from the 802.2/llc/snap header
213 hdrchop = (u8 *)p_ethhdr - (u8 *)p_rx_pd;
215 lbs_deb_hex(LBS_DEB_RX, "RX Data: LLC/SNAP",
216 (u8 *) &p_rx_pkt->rfc1042_hdr,
217 sizeof(p_rx_pkt->rfc1042_hdr));
219 /* Chop off the rxpd */
220 hdrchop = (u8 *)&p_rx_pkt->eth803_hdr - (u8 *)p_rx_pd;
223 /* Chop off the leading header bytes so the skb points to the start of
224 * either the reconstructed EthII frame or the 802.2/llc/snap frame
226 skb_pull(skb, hdrchop);
228 /* Take the data rate from the rxpd structure
229 * only if the rate is auto
231 if (priv->enablehwauto)
232 priv->cur_rate = lbs_fw_index_to_data_rate(p_rx_pd->rx_rate);
234 lbs_compute_rssi(priv, p_rx_pd);
236 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
237 dev->stats.rx_bytes += skb->len;
238 dev->stats.rx_packets++;
240 skb->protocol = eth_type_trans(skb, dev);
248 lbs_deb_leave_args(LBS_DEB_RX, "ret %d", ret);
251 EXPORT_SYMBOL_GPL(lbs_process_rxed_packet);
254 * @brief This function converts Tx/Rx rates from the Marvell WLAN format
255 * (see Table 2 in Section 3.1) to IEEE80211_RADIOTAP_RATE units (500 Kb/s)
257 * @param rate Input rate
258 * @return Output Rate (0 if invalid)
260 static u8 convert_mv_rate_to_radiotap(u8 rate)
267 case 2: /* 5.5 Mbps */
269 case 3: /* 11 Mbps */
271 /* case 4: reserved */
276 case 7: /* 12 Mbps */
278 case 8: /* 18 Mbps */
280 case 9: /* 24 Mbps */
282 case 10: /* 36 Mbps */
284 case 11: /* 48 Mbps */
286 case 12: /* 54 Mbps */
289 lbs_pr_alert("Invalid Marvell WLAN rate %i\n", rate);
294 * @brief This function processes a received 802.11 packet and forwards it
295 * to kernel/upper layer
297 * @param priv A pointer to struct lbs_private
298 * @param skb A pointer to skb which includes the received packet
301 static int process_rxed_802_11_packet(struct lbs_private *priv,
305 struct net_device *dev = priv->dev;
306 struct rx80211packethdr *p_rx_pkt;
308 struct rx_radiotap_hdr radiotap_hdr;
309 struct rx_radiotap_hdr *pradiotap_hdr;
311 lbs_deb_enter(LBS_DEB_RX);
313 p_rx_pkt = (struct rx80211packethdr *) skb->data;
314 prxpd = &p_rx_pkt->rx_pd;
316 /* lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data, min(skb->len, 100)); */
318 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
319 lbs_deb_rx("rx err: frame received with bad length\n");
320 dev->stats.rx_length_errors++;
326 lbs_deb_rx("rx data: skb->len-sizeof(RxPd) = %d-%zd = %zd\n",
327 skb->len, sizeof(struct rxpd), skb->len - sizeof(struct rxpd));
329 /* create the exported radio header */
331 /* radiotap header */
332 memset(&radiotap_hdr, 0, sizeof(radiotap_hdr));
333 /* XXX must check radiotap_hdr.hdr.it_pad for pad */
334 radiotap_hdr.hdr.it_len = cpu_to_le16 (sizeof(struct rx_radiotap_hdr));
335 radiotap_hdr.hdr.it_present = cpu_to_le32 (RX_RADIOTAP_PRESENT);
336 radiotap_hdr.rate = convert_mv_rate_to_radiotap(prxpd->rx_rate);
337 /* XXX must check no carryout */
338 radiotap_hdr.antsignal = prxpd->snr + prxpd->nf;
341 skb_pull(skb, sizeof(struct rxpd));
343 /* add space for the new radio header */
344 if ((skb_headroom(skb) < sizeof(struct rx_radiotap_hdr)) &&
345 pskb_expand_head(skb, sizeof(struct rx_radiotap_hdr), 0, GFP_ATOMIC)) {
346 lbs_pr_alert("%s: couldn't pskb_expand_head\n", __func__);
352 pradiotap_hdr = (void *)skb_push(skb, sizeof(struct rx_radiotap_hdr));
353 memcpy(pradiotap_hdr, &radiotap_hdr, sizeof(struct rx_radiotap_hdr));
355 /* Take the data rate from the rxpd structure
356 * only if the rate is auto
358 if (priv->enablehwauto)
359 priv->cur_rate = lbs_fw_index_to_data_rate(prxpd->rx_rate);
361 lbs_compute_rssi(priv, prxpd);
363 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
364 dev->stats.rx_bytes += skb->len;
365 dev->stats.rx_packets++;
367 skb->protocol = eth_type_trans(skb, priv->rtap_net_dev);
373 lbs_deb_leave_args(LBS_DEB_RX, "ret %d", ret);