drivers/net/wireless/ti/wlcore/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 "wlcore.h"
  28 #include "debug.h"
  29 #include "acx.h"
  30 #include "rx.h"
  31 #include "tx.h"
  32 #include "io.h"
  33 #include "hw_ops.h"
  34
  35 /*
  36  * TODO: this is here just for now, it must be removed when the data
  37  * operations are in place.
  38  */
  39 #include "../wl12xx/reg.h"
  40
  41 static u32 wlcore_rx_get_buf_size(struct wl1271 *wl,
  42                                   u32 rx_pkt_desc)
  43 {
  44         if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
  45                 return (rx_pkt_desc & ALIGNED_RX_BUF_SIZE_MASK) >>
  46                        ALIGNED_RX_BUF_SIZE_SHIFT;
  47
  48         return (rx_pkt_desc & RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
  49 }
  50
  51 static u32 wlcore_rx_get_align_buf_size(struct wl1271 *wl, u32 pkt_len)
  52 {
  53         if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
  54                 return ALIGN(pkt_len, WL12XX_BUS_BLOCK_SIZE);
  55
  56         return pkt_len;
  57 }
  58
  59 static void wl1271_rx_status(struct wl1271 *wl,
  60                              struct wl1271_rx_descriptor *desc,
  61                              struct ieee80211_rx_status *status,
  62                              u8 beacon)
  63 {
  64         memset(status, 0, sizeof(struct ieee80211_rx_status));
  65
  66         if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
  67                 status->band = IEEE80211_BAND_2GHZ;
  68         else
  69                 status->band = IEEE80211_BAND_5GHZ;
  70
  71         status->rate_idx = wlcore_rate_to_idx(wl, desc->rate, status->band);
  72
  73         /* 11n support */
  74         if (desc->rate <= wl->hw_min_ht_rate)
  75                 status->flag |= RX_FLAG_HT;
  76
  77         status->signal = desc->rssi;
  78
  79         /*
  80          * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
  81          * need to divide by two for now, but TI has been discussing about
  82          * changing it.  This needs to be rechecked.
  83          */
  84         wl->noise = desc->rssi - (desc->snr >> 1);
  85
  86         status->freq = ieee80211_channel_to_frequency(desc->channel,
  87                                                       status->band);
  88
  89         if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
  90                 u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
  91
  92                 status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
  93                                 RX_FLAG_DECRYPTED;
  94
  95                 if (unlikely(desc_err_code == WL1271_RX_DESC_MIC_FAIL)) {
  96                         status->flag |= RX_FLAG_MMIC_ERROR;
  97                         wl1271_warning("Michael MIC error");
  98                 }
  99         }
 100 }
 101
 102 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
 103                                  enum wl_rx_buf_align rx_align, u8 *hlid)
 104 {
 105         struct wl1271_rx_descriptor *desc;
 106         struct sk_buff *skb;
 107         struct ieee80211_hdr *hdr;
 108         u8 *buf;
 109         u8 beacon = 0;
 110         u8 is_data = 0;
 111         u8 reserved = 0;
 112         u16 seq_num;
 113
 114         /*
 115          * In PLT mode we seem to get frames and mac80211 warns about them,
 116          * workaround this by not retrieving them at all.
 117          */
 118         if (unlikely(wl->plt))
 119                 return -EINVAL;
 120
 121         if (rx_align == WLCORE_RX_BUF_UNALIGNED)
 122                 reserved = NET_IP_ALIGN;
 123
 124         /* the data read starts with the descriptor */
 125         desc = (struct wl1271_rx_descriptor *) data;
 126
 127         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
 128                 size_t len = length - sizeof(*desc);
 129                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
 130                 wake_up_interruptible(&wl->fwlog_waitq);
 131                 return 0;
 132         }
 133
 134         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
 135         /* discard corrupted packets */
 136         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
 137         case WL1271_RX_DESC_DECRYPT_FAIL:
 138                 wl1271_warning("corrupted packet in RX with status: 0x%x",
 139                                desc->status & WL1271_RX_DESC_STATUS_MASK);
 140                 return -EINVAL;
 141         case WL1271_RX_DESC_SUCCESS:
 142         case WL1271_RX_DESC_MIC_FAIL:
 143                 break;
 144         default:
 145                 wl1271_error("invalid RX descriptor status: 0x%x",
 146                              desc->status & WL1271_RX_DESC_STATUS_MASK);
 147                 return -EINVAL;
 148         }
 149
 150         /* skb length not included rx descriptor */
 151         skb = __dev_alloc_skb(length + reserved - sizeof(*desc), GFP_KERNEL);
 152         if (!skb) {
 153                 wl1271_error("Couldn't allocate RX frame");
 154                 return -ENOMEM;
 155         }
 156
 157         /* reserve the unaligned payload(if any) */
 158         skb_reserve(skb, reserved);
 159
 160         buf = skb_put(skb, length - sizeof(*desc));
 161
 162         /*
 163          * Copy packets from aggregation buffer to the skbs without rx
 164          * descriptor and with packet payload aligned care. In case of unaligned
 165          * packets copy the packets in offset of 2 bytes guarantee IP header
 166          * payload aligned to 4 bytes.
 167          */
 168         memcpy(buf, data + sizeof(*desc), length - sizeof(*desc));
 169         if (rx_align == WLCORE_RX_BUF_PADDED)
 170                 skb_pull(skb, NET_IP_ALIGN);
 171
 172         *hlid = desc->hlid;
 173
 174         hdr = (struct ieee80211_hdr *)skb->data;
 175         if (ieee80211_is_beacon(hdr->frame_control))
 176                 beacon = 1;
 177         if (ieee80211_is_data_present(hdr->frame_control))
 178                 is_data = 1;
 179
 180         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
 181
 182         seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
 183         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
 184                      skb->len - desc->pad_len,
 185                      beacon ? "beacon" : "",
 186                      seq_num, *hlid);
 187
 188         skb_trim(skb, skb->len - desc->pad_len);
 189
 190         skb_queue_tail(&wl->deferred_rx_queue, skb);
 191         queue_work(wl->freezable_wq, &wl->netstack_work);
 192
 193         return is_data;
 194 }
 195
 196 void wl12xx_rx(struct wl1271 *wl, struct wl12xx_fw_status *status)
 197 {
 198         unsigned long active_hlids[BITS_TO_LONGS(WL12XX_MAX_LINKS)] = {0};
 199         u32 buf_size;
 200         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 201         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 202         u32 rx_counter;
 203         u32 pkt_len, align_pkt_len;
 204         u32 pkt_offset, des;
 205         u8 hlid;
 206         enum wl_rx_buf_align rx_align;
 207
 208         while (drv_rx_counter != fw_rx_counter) {
 209                 buf_size = 0;
 210                 rx_counter = drv_rx_counter;
 211                 while (rx_counter != fw_rx_counter) {
 212                         des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
 213                         pkt_len = wlcore_rx_get_buf_size(wl, des);
 214                         align_pkt_len = wlcore_rx_get_align_buf_size(wl,
 215                                                                      pkt_len);
 216                         if (buf_size + align_pkt_len > WL1271_AGGR_BUFFER_SIZE)
 217                                 break;
 218                         buf_size += align_pkt_len;
 219                         rx_counter++;
 220                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 221                 }
 222
 223                 if (buf_size == 0) {
 224                         wl1271_warning("received empty data");
 225                         break;
 226                 }
 227
 228                 /* Read all available packets at once */
 229                 des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
 230                 wlcore_hw_prepare_read(wl, des, buf_size);
 231                 wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
 232                                  buf_size, true);
 233
 234                 /* Split data into separate packets */
 235                 pkt_offset = 0;
 236                 while (pkt_offset < buf_size) {
 237                         des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
 238                         pkt_len = wlcore_rx_get_buf_size(wl, des);
 239                         rx_align = wlcore_hw_get_rx_buf_align(wl, des);
 240
 241                         /*
 242                          * the handle data call can only fail in memory-outage
 243                          * conditions, in that case the received frame will just
 244                          * be dropped.
 245                          */
 246                         if (wl1271_rx_handle_data(wl,
 247                                                   wl->aggr_buf + pkt_offset,
 248                                                   pkt_len, rx_align,
 249                                                   &hlid) == 1) {
 250                                 if (hlid < WL12XX_MAX_LINKS)
 251                                         __set_bit(hlid, active_hlids);
 252                                 else
 253                                         WARN(1,
 254                                              "hlid exceeded WL12XX_MAX_LINKS "
 255                                              "(%d)\n", hlid);
 256                         }
 257
 258                         wl->rx_counter++;
 259                         drv_rx_counter++;
 260                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 261                         pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
 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 & WLCORE_QUIRK_END_OF_TRANSACTION)
 270                 wl1271_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
 271                                wl->rx_counter);
 272
 273         wl12xx_rearm_rx_streaming(wl, active_hlids);
 274 }