drivers/net/wireless/wl12xx/wl1271_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 "wl1271.h"
  25 #include "wl1271_acx.h"
  26 #include "wl1271_reg.h"
  27 #include "wl1271_rx.h"
  28 #include "wl1271_spi.h"
  29
  30 static u8 wl1271_rx_get_mem_block(struct wl1271_fw_status *status,
  31                                   u32 drv_rx_counter)
  32 {
  33         return status->rx_pkt_descs[drv_rx_counter] & RX_MEM_BLOCK_MASK;
  34 }
  35
  36 static u32 wl1271_rx_get_buf_size(struct wl1271_fw_status *status,
  37                                  u32 drv_rx_counter)
  38 {
  39         return (status->rx_pkt_descs[drv_rx_counter] & RX_BUF_SIZE_MASK) >>
  40                 RX_BUF_SIZE_SHIFT_DIV;
  41 }
  42
  43 /* The values of this table must match the wl1271_rates[] array */
  44 static u8 wl1271_rx_rate_to_idx[] = {
  45         /* MCS rates are used only with 11n */
  46         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS7 */
  47         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS6 */
  48         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS5 */
  49         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS4 */
  50         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS3 */
  51         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS2 */
  52         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS1 */
  53         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_MCS0 */
  54
  55         11,                         /* WL1271_RATE_54   */
  56         10,                         /* WL1271_RATE_48   */
  57         9,                          /* WL1271_RATE_36   */
  58         8,                          /* WL1271_RATE_24   */
  59
  60         /* TI-specific rate */
  61         WL1271_RX_RATE_UNSUPPORTED, /* WL1271_RATE_22   */
  62
  63         7,                          /* WL1271_RATE_18   */
  64         6,                          /* WL1271_RATE_12   */
  65         3,                          /* WL1271_RATE_11   */
  66         5,                          /* WL1271_RATE_9    */
  67         4,                          /* WL1271_RATE_6    */
  68         2,                          /* WL1271_RATE_5_5  */
  69         1,                          /* WL1271_RATE_2    */
  70         0                           /* WL1271_RATE_1    */
  71 };
  72
  73 static void wl1271_rx_status(struct wl1271 *wl,
  74                              struct wl1271_rx_descriptor *desc,
  75                              struct ieee80211_rx_status *status,
  76                              u8 beacon)
  77 {
  78         memset(status, 0, sizeof(struct ieee80211_rx_status));
  79
  80         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
  81                 status->band = IEEE80211_BAND_2GHZ;
  82         else
  83                 wl1271_warning("unsupported band 0x%x",
  84                                desc->flags & WL1271_RX_DESC_BAND_MASK);
  85
  86         /*
  87          * FIXME: Add mactime handling.  For IBSS (ad-hoc) we need to get the
  88          * timestamp from the beacon (acx_tsf_info).  In BSS mode (infra) we
  89          * only need the mactime for monitor mode.  For now the mactime is
  90          * not valid, so RX_FLAG_TSFT should not be set
  91          */
  92         status->signal = desc->rssi;
  93
  94         /*
  95          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
  96          * need to divide by two for now, but TI has been discussing about
  97          * changing it.  This needs to be rechecked.
  98          */
  99         status->noise = desc->rssi - (desc->snr >> 1);
 100
 101         status->freq = ieee80211_channel_to_frequency(desc->channel);
 102
 103         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
 104                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED;
 105
 106                 if (likely(!(desc->flags & WL1271_RX_DESC_DECRYPT_FAIL)))
 107                         status->flag |= RX_FLAG_DECRYPTED;
 108
 109                 if (unlikely(desc->flags & WL1271_RX_DESC_MIC_FAIL))
 110                         status->flag |= RX_FLAG_MMIC_ERROR;
 111         }
 112
 113         status->rate_idx = wl1271_rx_rate_to_idx[desc->rate];
 114
 115         if (status->rate_idx == WL1271_RX_RATE_UNSUPPORTED)
 116                 wl1271_warning("unsupported rate");
 117 }
 118
 119 static void wl1271_rx_handle_data(struct wl1271 *wl, u32 length)
 120 {
 121         struct ieee80211_rx_status rx_status;
 122         struct wl1271_rx_descriptor *desc;
 123         struct sk_buff *skb;
 124         u16 *fc;
 125         u8 *buf;
 126         u8 beacon = 0;
 127
 128         skb = dev_alloc_skb(length);
 129         if (!skb) {
 130                 wl1271_error("Couldn't allocate RX frame");
 131                 return;
 132         }
 133
 134         buf = skb_put(skb, length);
 135         wl1271_spi_read(wl, WL1271_SLV_MEM_DATA, buf, length, true);
 136
 137         /* the data read starts with the descriptor */
 138         desc = (struct wl1271_rx_descriptor *) buf;
 139
 140         /* now we pull the descriptor out of the buffer */
 141         skb_pull(skb, sizeof(*desc));
 142
 143         fc = (u16 *)skb->data;
 144         if ((*fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
 145                 beacon = 1;
 146
 147         wl1271_rx_status(wl, desc, &rx_status, beacon);
 148
 149         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb, skb->len,
 150                      beacon ? "beacon" : "");
 151
 152         memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
 153         ieee80211_rx(wl->hw, skb);
 154 }
 155
 156 void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_status *status)
 157 {
 158         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
 159         u32 buf_size;
 160         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 161         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 162         u32 mem_block;
 163
 164         while (drv_rx_counter != fw_rx_counter) {
 165                 mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
 166                 buf_size = wl1271_rx_get_buf_size(status, drv_rx_counter);
 167
 168                 if (buf_size == 0) {
 169                         wl1271_warning("received empty data");
 170                         break;
 171                 }
 172
 173                 wl->rx_mem_pool_addr.addr =
 174                         (mem_block << 8) + wl_mem_map->packet_memory_pool_start;
 175                 wl->rx_mem_pool_addr.addr_extra =
 176                         wl->rx_mem_pool_addr.addr + 4;
 177
 178                 /* Choose the block we want to read */
 179                 wl1271_spi_write(wl, WL1271_SLV_REG_DATA,
 180                                  &wl->rx_mem_pool_addr,
 181                                  sizeof(wl->rx_mem_pool_addr), false);
 182
 183                 wl1271_rx_handle_data(wl, buf_size);
 184
 185                 wl->rx_counter++;
 186                 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 187         }
 188
 189         wl1271_spi_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
 190 }