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         u32 pkt_data_len;
 114
 115         /*
 116          * In PLT mode we seem to get frames and mac80211 warns about them,
 117          * workaround this by not retrieving them at all.
 118          */
 119         if (unlikely(wl->plt))
 120                 return -EINVAL;
 121
 122         pkt_data_len = wlcore_hw_get_rx_packet_len(wl, data, length);
 123         if (!pkt_data_len) {
 124                 wl1271_error("Invalid packet arrived from HW. length %d",
 125                              length);
 126                 return -EINVAL;
 127         }
 128
 129         if (rx_align == WLCORE_RX_BUF_UNALIGNED)
 130                 reserved = NET_IP_ALIGN;
 131
 132         /* the data read starts with the descriptor */
 133         desc = (struct wl1271_rx_descriptor *) data;
 134
 135         if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
 136                 size_t len = length - sizeof(*desc);
 137                 wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
 138                 wake_up_interruptible(&wl->fwlog_waitq);
 139                 return 0;
 140         }
 141
 142         switch (desc->status & WL1271_RX_DESC_STATUS_MASK) {
 143         /* discard corrupted packets */
 144         case WL1271_RX_DESC_DRIVER_RX_Q_FAIL:
 145         case WL1271_RX_DESC_DECRYPT_FAIL:
 146                 wl1271_warning("corrupted packet in RX with status: 0x%x",
 147                                desc->status & WL1271_RX_DESC_STATUS_MASK);
 148                 return -EINVAL;
 149         case WL1271_RX_DESC_SUCCESS:
 150         case WL1271_RX_DESC_MIC_FAIL:
 151                 break;
 152         default:
 153                 wl1271_error("invalid RX descriptor status: 0x%x",
 154                              desc->status & WL1271_RX_DESC_STATUS_MASK);
 155                 return -EINVAL;
 156         }
 157
 158         /* skb length not including rx descriptor */
 159         skb = __dev_alloc_skb(pkt_data_len + reserved, GFP_KERNEL);
 160         if (!skb) {
 161                 wl1271_error("Couldn't allocate RX frame");
 162                 return -ENOMEM;
 163         }
 164
 165         /* reserve the unaligned payload(if any) */
 166         skb_reserve(skb, reserved);
 167
 168         buf = skb_put(skb, pkt_data_len);
 169
 170         /*
 171          * Copy packets from aggregation buffer to the skbs without rx
 172          * descriptor and with packet payload aligned care. In case of unaligned
 173          * packets copy the packets in offset of 2 bytes guarantee IP header
 174          * payload aligned to 4 bytes.
 175          */
 176         memcpy(buf, data + sizeof(*desc), pkt_data_len);
 177         if (rx_align == WLCORE_RX_BUF_PADDED)
 178                 skb_pull(skb, NET_IP_ALIGN);
 179
 180         *hlid = desc->hlid;
 181
 182         hdr = (struct ieee80211_hdr *)skb->data;
 183         if (ieee80211_is_beacon(hdr->frame_control))
 184                 beacon = 1;
 185         if (ieee80211_is_data_present(hdr->frame_control))
 186                 is_data = 1;
 187
 188         wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
 189
 190         seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
 191         wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
 192                      skb->len - desc->pad_len,
 193                      beacon ? "beacon" : "",
 194                      seq_num, *hlid);
 195
 196         skb_queue_tail(&wl->deferred_rx_queue, skb);
 197         queue_work(wl->freezable_wq, &wl->netstack_work);
 198
 199         return is_data;
 200 }
 201
 202 void wl12xx_rx(struct wl1271 *wl, struct wl_fw_status *status)
 203 {
 204         unsigned long active_hlids[BITS_TO_LONGS(WL12XX_MAX_LINKS)] = {0};
 205         u32 buf_size;
 206         u32 fw_rx_counter  = status->fw_rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 207         u32 drv_rx_counter = wl->rx_counter & NUM_RX_PKT_DESC_MOD_MASK;
 208         u32 rx_counter;
 209         u32 pkt_len, align_pkt_len;
 210         u32 pkt_offset, des;
 211         u8 hlid;
 212         enum wl_rx_buf_align rx_align;
 213
 214         while (drv_rx_counter != fw_rx_counter) {
 215                 buf_size = 0;
 216                 rx_counter = drv_rx_counter;
 217                 while (rx_counter != fw_rx_counter) {
 218                         des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
 219                         pkt_len = wlcore_rx_get_buf_size(wl, des);
 220                         align_pkt_len = wlcore_rx_get_align_buf_size(wl,
 221                                                                      pkt_len);
 222                         if (buf_size + align_pkt_len > WL1271_AGGR_BUFFER_SIZE)
 223                                 break;
 224                         buf_size += align_pkt_len;
 225                         rx_counter++;
 226                         rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 227                 }
 228
 229                 if (buf_size == 0) {
 230                         wl1271_warning("received empty data");
 231                         break;
 232                 }
 233
 234                 /* Read all available packets at once */
 235                 des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
 236                 wlcore_hw_prepare_read(wl, des, buf_size);
 237                 wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
 238                                  buf_size, true);
 239
 240                 /* Split data into separate packets */
 241                 pkt_offset = 0;
 242                 while (pkt_offset < buf_size) {
 243                         des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
 244                         pkt_len = wlcore_rx_get_buf_size(wl, des);
 245                         rx_align = wlcore_hw_get_rx_buf_align(wl, des);
 246
 247                         /*
 248                          * the handle data call can only fail in memory-outage
 249                          * conditions, in that case the received frame will just
 250                          * be dropped.
 251                          */
 252                         if (wl1271_rx_handle_data(wl,
 253                                                   wl->aggr_buf + pkt_offset,
 254                                                   pkt_len, rx_align,
 255                                                   &hlid) == 1) {
 256                                 if (hlid < WL12XX_MAX_LINKS)
 257                                         __set_bit(hlid, active_hlids);
 258                                 else
 259                                         WARN(1,
 260                                              "hlid exceeded WL12XX_MAX_LINKS "
 261                                              "(%d)\n", hlid);
 262                         }
 263
 264                         wl->rx_counter++;
 265                         drv_rx_counter++;
 266                         drv_rx_counter &= NUM_RX_PKT_DESC_MOD_MASK;
 267                         pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
 268                 }
 269         }
 270
 271         /*
 272          * Write the driver's packet counter to the FW. This is only required
 273          * for older hardware revisions
 274          */
 275         if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION)
 276                 wl1271_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
 277                                wl->rx_counter);
 278
 279         wl12xx_rearm_rx_streaming(wl, active_hlids);
 280 }