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         /* FIXME: Should this be optimized? */
  95         status->qual = (desc->rssi - WL1271_RX_MIN_RSSI) * 100 /
  96                 (WL1271_RX_MAX_RSSI - WL1271_RX_MIN_RSSI);
  97         status->qual = min(status->qual, 100);
  98         status->qual = max(status->qual, 0);
  99
 100         /*
 101          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
 102          * need to divide by two for now, but TI has been discussing about
 103          * changing it.  This needs to be rechecked.
 104          */
 105         status->noise = desc->rssi - (desc->snr >> 1);
 106
 107         status->freq = ieee80211_channel_to_frequency(desc->channel);
 108
 109         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
 110                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED;
 111
 112                 if (likely(!(desc->flags & WL1271_RX_DESC_DECRYPT_FAIL)))
 113                         status->flag |= RX_FLAG_DECRYPTED;
 114
 115                 if (unlikely(desc->flags & WL1271_RX_DESC_MIC_FAIL))
 116                         status->flag |= RX_FLAG_MMIC_ERROR;
 117         }
 118
 119         status->rate_idx = wl1271_rx_rate_to_idx[desc->rate];
 120
 121         if (status->rate_idx == WL1271_RX_RATE_UNSUPPORTED)
 122                 wl1271_warning("unsupported rate");
 123 }
 124
 125 static void wl1271_rx_handle_data(struct wl1271 *wl, u32 length)
 126 {
 127         struct ieee80211_rx_status rx_status;
 128         struct wl1271_rx_descriptor *desc;
 129         struct sk_buff *skb;
 130         u16 *fc;
 131         u8 *buf;
 132         u8 beacon = 0;
 133
 134         skb = dev_alloc_skb(length);
 135         if (!skb) {
 136                 wl1271_error("Couldn't allocate RX frame");
 137                 return;
 138         }
 139
 140         buf = skb_put(skb, length);
 141         wl1271_spi_reg_read(wl, WL1271_SLV_MEM_DATA, buf, length, true);
 142
 143         /* the data read starts with the descriptor */
 144         desc = (struct wl1271_rx_descriptor *) buf;
 145
 146         /* now we pull the descriptor out of the buffer */
 147         skb_pull(skb, sizeof(*desc));
 148
 149         fc = (u16 *)skb->data;
 150         if ((*fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
 151                 beacon = 1;
 152
 153         wl1271_rx_status(wl, desc, &rx_status, beacon);
 154
 155         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s", skb, skb->len,
 156                      beacon ? "beacon" : "");
 157
 158         memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
 159         ieee80211_rx(wl->hw, skb);
 160 }
 161
 162 void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_status *status)
 163 {
 164         struct wl1271_acx_mem_map *wl_mem_map = wl->target_mem_map;
 165         u32 buf_size;
 166         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 167         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 168         u32 mem_block;
 169
 170         while (drv_rx_counter != fw_rx_counter) {
 171                 mem_block = wl1271_rx_get_mem_block(status, drv_rx_counter);
 172                 buf_size = wl1271_rx_get_buf_size(status, drv_rx_counter);
 173
 174                 if (buf_size == 0) {
 175                         wl1271_warning("received empty data");
 176                         break;
 177                 }
 178
 179                 wl->rx_mem_pool_addr.addr =
 180                         (mem_block << 8) + wl_mem_map->packet_memory_pool_start;
 181                 wl->rx_mem_pool_addr.addr_extra =
 182                         wl->rx_mem_pool_addr.addr + 4;
 183
 184                 /* Choose the block we want to read */
 185                 wl1271_spi_reg_write(wl, WL1271_SLV_REG_DATA,
 186                                      &wl->rx_mem_pool_addr,
 187                                      sizeof(wl->rx_mem_pool_addr), false);
 188
 189                 wl1271_rx_handle_data(wl, buf_size);
 190
 191                 wl->rx_counter++;
 192                 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 193         }
 194
 195         wl1271_reg_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
 196
 197         /* This is a workaround for some problems in the chip */
 198         wl1271_reg_write32(wl, RX_DRIVER_DUMMY_WRITE_ADDRESS, 0x1);
 199
 200 }