drivers/net/wireless/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 "acx.h"
  29 #include "reg.h"
  30 #include "rx.h"
  31 #include "io.h"
  32
  33 static u8 wl12xx_rx_get_mem_block(struct wl12xx_fw_status *status,
  34                                   u32 drv_rx_counter)
  35 {
  36         return le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  37                 RX_MEM_BLOCK_MASK;
  38 }
  39
  40 static u32 wl12xx_rx_get_buf_size(struct wl12xx_fw_status *status,
  41                                  u32 drv_rx_counter)
  42 {
  43         return (le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  44                 RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
  45 }
  46
  47 static bool wl12xx_rx_get_unaligned(struct wl12xx_fw_status *status,
  48                                     u32 drv_rx_counter)
  49 {
  50         /* Convert the value to bool */
  51         return !!(le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]) &
  52                 RX_BUF_UNALIGNED_PAYLOAD);
  53 }
  54
  55 static void wl1271_rx_status(struct wl1271 *wl,
  56                              struct wl1271_rx_descriptor *desc,
  57                              struct ieee80211_rx_status *status,
  58                              u8 beacon)
  59 {
  60         memset(status, 0, sizeof(struct ieee80211_rx_status));
  61
  62         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
  63                 status->band = IEEE80211_BAND_2GHZ;
  64         else
  65                 status->band = IEEE80211_BAND_5GHZ;
  66
  67         status->rate_idx = wl1271_rate_to_idx(desc->rate, status->band);
  68
  69 #ifdef CONFIG_WL12XX_HT
  70         /* 11n support */
  71         if (desc->rate <= CONF_HW_RXTX_RATE_MCS0)
  72                 status->flag |= RX_FLAG_HT;
  73 #endif
  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)
 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
 111         /*
 112          * In PLT mode we seem to get frames and mac80211 warns about them,
 113          * workaround this by not retrieving them at all.
 114          */
 115         if (unlikely(wl->state == WL1271_STATE_PLT))
 116                 return -EINVAL;
 117
 118         /* the data read starts with the descriptor */
 119         desc = (struct wl1271_rx_descriptor *) data;
 120
 121         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
 122                 size_t len = length - sizeof(*desc);
 123                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
 124                 wake_up_interruptible(&wl->fwlog_waitq);
 125                 return 0;
 126         }
 127
 128         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
 129         /* discard corrupted packets */
 130         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
 131         case WL1271_RX_DESC_DECRYPT_FAIL:
 132                 wl1271_warning("corrupted packet in RX with status: 0x%x",
 133                                desc->status & WL1271_RX_DESC_STATUS_MASK);
 134                 return -EINVAL;
 135         case WL1271_RX_DESC_SUCCESS:
 136         case WL1271_RX_DESC_MIC_FAIL:
 137                 break;
 138         default:
 139                 wl1271_error("invalid RX descriptor status: 0x%x",
 140                              desc->status & WL1271_RX_DESC_STATUS_MASK);
 141                 return -EINVAL;
 142         }
 143
 144         /* skb length not included rx descriptor */
 145         skb = __dev_alloc_skb(length + reserved - sizeof(*desc), GFP_KERNEL);
 146         if (!skb) {
 147                 wl1271_error("Couldn't allocate RX frame");
 148                 return -ENOMEM;
 149         }
 150
 151         /* reserve the unaligned payload(if any) */
 152         skb_reserve(skb, reserved);
 153
 154         buf = skb_put(skb, length - sizeof(*desc));
 155
 156         /*
 157          * Copy packets from aggregation buffer to the skbs without rx
 158          * descriptor and with packet payload aligned care. In case of unaligned
 159          * packets copy the packets in offset of 2 bytes guarantee IP header
 160          * payload aligned to 4 bytes.
 161          */
 162         memcpy(buf, data + sizeof(*desc), length - sizeof(*desc));
 163
 164         hdr = (struct ieee80211_hdr *)skb->data;
 165         if (ieee80211_is_beacon(hdr->frame_control))
 166                 beacon = 1;
 167         if (ieee80211_is_data_present(hdr->frame_control))
 168                 is_data = 1;
 169
 170         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
 171
 172         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb,
 173                      skb->len - desc->pad_len,
 174                      beacon ? "beacon" : "");
 175
 176         skb_trim(skb, skb->len - desc->pad_len);
 177
 178         skb_queue_tail(&wl->deferred_rx_queue, skb);
 179         queue_work(wl->freezable_wq, &wl->netstack_work);
 180
 181         return is_data;
 182 }
 183
 184 void wl12xx_rx(struct wl1271 *wl, struct wl12xx_fw_status *status)
 185 {
 186         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
 187         u32 buf_size;
 188         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 189         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 190         u32 rx_counter;
 191         u32 mem_block;
 192         u32 pkt_length;
 193         u32 pkt_offset;
 194         bool is_ap = (wl->bss_type == BSS_TYPE_AP_BSS);
 195         bool had_data = false;
 196         bool unaligned = false;
 197
 198         while (drv_rx_counter != fw_rx_counter) {
 199                 buf_size = 0;
 200                 rx_counter = drv_rx_counter;
 201                 while (rx_counter != fw_rx_counter) {
 202                         pkt_length = wl12xx_rx_get_buf_size(status, rx_counter);
 203                         if (buf_size + pkt_length > WL1271_AGGR_BUFFER_SIZE)
 204                                 break;
 205                         buf_size += pkt_length;
 206                         rx_counter++;
 207                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 208                 }
 209
 210                 if (buf_size == 0) {
 211                         wl1271_warning("received empty data");
 212                         break;
 213                 }
 214
 215                 if (wl->chip.id != CHIP_ID_1283_PG20) {
 216                         /*
 217                          * Choose the block we want to read
 218                          * For aggregated packets, only the first memory block
 219                          * should be retrieved. The FW takes care of the rest.
 220                          */
 221                         mem_block = wl12xx_rx_get_mem_block(status,
 222                                                             drv_rx_counter);
 223
 224                         wl->rx_mem_pool_addr.addr = (mem_block << 8) +
 225                            le32_to_cpu(wl_mem_map->packet_memory_pool_start);
 226
 227                         wl->rx_mem_pool_addr.addr_extra =
 228                                 wl->rx_mem_pool_addr.addr + 4;
 229
 230                         wl1271_write(wl, WL1271_SLV_REG_DATA,
 231                                      &wl->rx_mem_pool_addr,
 232                                      sizeof(wl->rx_mem_pool_addr), false);
 233                 }
 234
 235                 /* Read all available packets at once */
 236                 wl1271_read(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
 237                                 buf_size, true);
 238
 239                 /* Split data into separate packets */
 240                 pkt_offset = 0;
 241                 while (pkt_offset < buf_size) {
 242                         pkt_length = wl12xx_rx_get_buf_size(status,
 243                                         drv_rx_counter);
 244
 245                         unaligned = wl12xx_rx_get_unaligned(status,
 246                                         drv_rx_counter);
 247
 248                         /*
 249                          * the handle data call can only fail in memory-outage
 250                          * conditions, in that case the received frame will just
 251                          * be dropped.
 252                          */
 253                         if (wl1271_rx_handle_data(wl,
 254                                                   wl->aggr_buf + pkt_offset,
 255                                                   pkt_length, unaligned) == 1)
 256                                 had_data = true;
 257
 258                         wl->rx_counter++;
 259                         drv_rx_counter++;
 260                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 261                         pkt_offset += pkt_length;
 262                 }
 263         }
 264
 265         /*
 266          * Write the driver's packet counter to the FW. This is only required
 267          * for older hardware revisions
 268          */
 269         if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
 270                 wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
 271
 272         if (!is_ap && wl->conf.rx_streaming.interval && had_data &&
 273             (wl->conf.rx_streaming.always ||
 274              test_bit(WL1271_FLAG_SOFT_GEMINI, &wl->flags))) {
 275                 u32 timeout = wl->conf.rx_streaming.duration;
 276
 277                 /* restart rx streaming */
 278                 if (!test_bit(WL1271_FLAG_RX_STREAMING_STARTED, &wl->flags))
 279                         ieee80211_queue_work(wl->hw,
 280                                              &wl->rx_streaming_enable_work);
 281
 282                 mod_timer(&wl->rx_streaming_timer,
 283                           jiffies + msecs_to_jiffies(timeout));
 284         }
 285 }