drivers/net/wireless/ti/wl12xx/rx.c

   1 /*
   2  * This file is part of wl1271
   3  *
   4  * Copyright (C) 2009 Nokia Corporation
   5  *
   6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  *
  22  */
  23
  24 #include <linux/gfp.h>
  25 #include <linux/sched.h>
  26
  27 #include "wl12xx.h"
  28 #include "debug.h"
  29 #include "acx.h"
  30 #include "reg.h"
  31 #include "rx.h"
  32 #include "tx.h"
  33 #include "io.h"
  34
  35 static u8 wl12xx_rx_get_mem_block(struct wl12xx_fw_status *status,
  36                                   u32 drv_rx_counter)
  37 {
  38         return le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  39                 RX_MEM_BLOCK_MASK;
  40 }
  41
  42 static u32 wl12xx_rx_get_buf_size(struct wl12xx_fw_status *status,
  43                                  u32 drv_rx_counter)
  44 {
  45         return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  46                 RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
  47 }
  48
  49 static bool wl12xx_rx_get_unaligned(struct wl12xx_fw_status *status,
  50                                     u32 drv_rx_counter)
  51 {
  52         /* Convert the value to bool */
  53         return !!(le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  54                 RX_BUF_UNALIGNED_PAYLOAD);
  55 }
  56
  57 static void wl1271_rx_status(struct wl1271 *wl,
  58                              struct wl1271_rx_descriptor *desc,
  59                              struct ieee80211_rx_status *status,
  60                              u8 beacon)
  61 {
  62         memset(status, 0, sizeof(struct ieee80211_rx_status));
  63
  64         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
  65                 status->band = IEEE80211_BAND_2GHZ;
  66         else
  67                 status->band = IEEE80211_BAND_5GHZ;
  68
  69         status->rate_idx = wl1271_rate_to_idx(desc->rate, status->band);
  70
  71         /* 11n support */
  72         if (desc->rate <= CONF_HW_RXTX_RATE_MCS0)
  73                 status->flag |= RX_FLAG_HT;
  74
  75         status->signal = desc->rssi;
  76
  77         /*
  78          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
  79          * need to divide by two for now, but TI has been discussing about
  80          * changing it.  This needs to be rechecked.
  81          */
  82         wl->noise = desc->rssi - (desc->snr >> 1);
  83
  84         status->freq = ieee80211_channel_to_frequency(desc->channel,
  85                                                       status->band);
  86
  87         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
  88                 u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
  89
  90                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
  91                                 RX_FLAG_DECRYPTED;
  92
  93                 if (unlikely(desc_err_code == WL1271_RX_DESC_MIC_FAIL)) {
  94                         status->flag |= RX_FLAG_MMIC_ERROR;
  95                         wl1271_warning("Michael MIC error");
  96                 }
  97         }
  98 }
  99
 100 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
 101                                  bool unaligned, u8 *hlid)
 102 {
 103         struct wl1271_rx_descriptor *desc;
 104         struct sk_buff *skb;
 105         struct ieee80211_hdr *hdr;
 106         u8 *buf;
 107         u8 beacon = 0;
 108         u8 is_data = 0;
 109         u8 reserved = unaligned ? NET_IP_ALIGN : 0;
 110         u16 seq_num;
 111
 112         /*
 113          * In PLT mode we seem to get frames and mac80211 warns about them,
 114          * workaround this by not retrieving them at all.
 115          */
 116         if (unlikely(wl->plt))
 117                 return -EINVAL;
 118
 119         /* the data read starts with the descriptor */
 120         desc = (struct wl1271_rx_descriptor *) data;
 121
 122         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
 123                 size_t len = length - sizeof(*desc);
 124                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
 125                 wake_up_interruptible(&wl->fwlog_waitq);
 126                 return 0;
 127         }
 128
 129         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
 130         /* discard corrupted packets */
 131         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
 132         case WL1271_RX_DESC_DECRYPT_FAIL:
 133                 wl1271_warning("corrupted packet in RX with status: 0x%x",
 134                                desc->status & WL1271_RX_DESC_STATUS_MASK);
 135                 return -EINVAL;
 136         case WL1271_RX_DESC_SUCCESS:
 137         case WL1271_RX_DESC_MIC_FAIL:
 138                 break;
 139         default:
 140                 wl1271_error("invalid RX descriptor status: 0x%x",
 141                              desc->status & WL1271_RX_DESC_STATUS_MASK);
 142                 return -EINVAL;
 143         }
 144
 145         /* skb length not included rx descriptor */
 146         skb = __dev_alloc_skb(length + reserved - sizeof(*desc), GFP_KERNEL);
 147         if (!skb) {
 148                 wl1271_error("Couldn't allocate RX frame");
 149                 return -ENOMEM;
 150         }
 151
 152         /* reserve the unaligned payload(if any) */
 153         skb_reserve(skb, reserved);
 154
 155         buf = skb_put(skb, length - sizeof(*desc));
 156
 157         /*
 158          * Copy packets from aggregation buffer to the skbs without rx
 159          * descriptor and with packet payload aligned care. In case of unaligned
 160          * packets copy the packets in offset of 2 bytes guarantee IP header
 161          * payload aligned to 4 bytes.
 162          */
 163         memcpy(buf, data + sizeof(*desc), length - sizeof(*desc));
 164         *hlid = desc->hlid;
 165
 166         hdr = (struct ieee80211_hdr *)skb->data;
 167         if (ieee80211_is_beacon(hdr->frame_control))
 168                 beacon = 1;
 169         if (ieee80211_is_data_present(hdr->frame_control))
 170                 is_data = 1;
 171
 172         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
 173
 174         seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
 175         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
 176                      skb->len - desc->pad_len,
 177                      beacon ? "beacon" : "",
 178                      seq_num, *hlid);
 179
 180         skb_trim(skb, skb->len - desc->pad_len);
 181
 182         skb_queue_tail(&wl->deferred_rx_queue, skb);
 183         queue_work(wl->freezable_wq, &wl->netstack_work);
 184
 185         return is_data;
 186 }
 187
 188 void wl12xx_rx(struct wl1271 *wl, struct wl12xx_fw_status *status)
 189 {
 190         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
 191         unsigned long active_hlids[BITS_TO_LONGS(WL12XX_MAX_LINKS)] = {0};
 192         u32 buf_size;
 193         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 194         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 195         u32 rx_counter;
 196         u32 mem_block;
 197         u32 pkt_length;
 198         u32 pkt_offset;
 199         u8 hlid;
 200         bool unaligned = false;
 201
 202         while (drv_rx_counter != fw_rx_counter) {
 203                 buf_size = 0;
 204                 rx_counter = drv_rx_counter;
 205                 while (rx_counter != fw_rx_counter) {
 206                         pkt_length = wl12xx_rx_get_buf_size(status, rx_counter);
 207                         if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
 208                                 break;
 209                         buf_size += pkt_length;
 210                         rx_counter++;
 211                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 212                 }
 213
 214                 if (buf_size == 0) {
 215                         wl1271_warning("received empty data");
 216                         break;
 217                 }
 218
 219                 if (wl->chip.id != CHIP_ID_1283_PG20) {
 220                         /*
 221                          * Choose the block we want to read
 222                          * For aggregated packets, only the first memory block
 223                          * should be retrieved. The FW takes care of the rest.
 224                          */
 225                         mem_block = wl12xx_rx_get_mem_block(status,
 226                                                             drv_rx_counter);
 227
 228                         wl->rx_mem_pool_addr.addr = (mem_block << 8) +
 229                            le32_to_cpu(wl_mem_map->packet_memory_pool_start);
 230
 231                         wl->rx_mem_pool_addr.addr_extra =
 232                                 wl->rx_mem_pool_addr.addr + 4;
 233
 234                         wl1271_write(wl, WL1271_SLV_REG_DATA,
 235                                      &wl->rx_mem_pool_addr,
 236                                      sizeof(wl->rx_mem_pool_addr), false);
 237                 }
 238
 239                 /* Read all available packets at once */
 240                 wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
 241                                 buf_size, true);
 242
 243                 /* Split data into separate packets */
 244                 pkt_offset = 0;
 245                 while (pkt_offset < buf_size) {
 246                         pkt_length = wl12xx_rx_get_buf_size(status,
 247                                         drv_rx_counter);
 248
 249                         unaligned = wl12xx_rx_get_unaligned(status,
 250                                         drv_rx_counter);
 251
 252                         /*
 253                          * the handle data call can only fail in memory-outage
 254                          * conditions, in that case the received frame will just
 255                          * be dropped.
 256                          */
 257                         if (wl1271_rx_handle_data(wl,
 258                                                   wl->aggr_buf + pkt_offset,
 259                                                   pkt_length, unaligned,
 260                                                   &hlid) == 1) {
 261                                 if (hlid < WL12XX_MAX_LINKS)
 262                                         __set_bit(hlid, active_hlids);
 263                                 else
 264                                         WARN(1,
 265                                              "hlid exceeded WL12XX_MAX_LINKS "
 266                                              "(%d)\n", hlid);
 267                         }
 268
 269                         wl->rx_counter++;
 270                         drv_rx_counter++;
 271                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 272                         pkt_offset += pkt_length;
 273                 }
 274         }
 275
 276         /*
 277          * Write the driver's packet counter to the FW. This is only required
 278          * for older hardware revisions
 279          */
 280         if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
 281                 wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
 282
 283         wl12xx_rearm_rx_streaming(wl, active_hlids);
 284 }