carlfw/src/wlanrx.c

   1 /*
   2  * carl9170 firmware - used by the ar9170 wireless device
   3  *
   4  * WLAN receive routines
   5  *
   6  * Copyright (c) 2000-2005 ZyDAS Technology Corporation
   7  * Copyright (c) 2007-2009 Atheros Communications, Inc.
   8  * Copyright    2009    Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2009-2012  Christian Lamparter <chunkeey@googlemail.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License along
  22  * with this program; If not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25 #include "carl9170.h"
  26 #include "shared/phy.h"
  27 #include "hostif.h"
  28 #include "timer.h"
  29 #include "wl.h"
  30 #include "printf.h"
  31 #include "rf.h"
  32 #include "linux/ieee80211.h"
  33 #include "wol.h"
  34
  35 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
  36 {
  37         struct carl9170_bar_ctx *tmp;
  38
  39         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx];
  40         fw.wlan.ba_tail_idx++;
  41         fw.wlan.ba_tail_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
  42         if (fw.wlan.queued_ba < CONFIG_CARL9170FW_BACK_REQS_NUM)
  43                 fw.wlan.queued_ba++;
  44
  45         return tmp;
  46 }
  47
  48 static void handle_bar(struct dma_desc *desc __unused, struct ieee80211_hdr *hdr,
  49                        unsigned int len, unsigned int mac_err)
  50 {
  51         struct ieee80211_bar *bar;
  52         struct carl9170_bar_ctx *ctx;
  53
  54         if (unlikely(mac_err)) {
  55                 /*
  56                  * This check does a number of things:
  57                  * 1. checks if the frame is in good nick
  58                  * 2. checks if the RA (MAC) matches
  59                  */
  60                 return ;
  61         }
  62
  63         if (unlikely(len < (sizeof(struct ieee80211_bar) + FCS_LEN))) {
  64                 /*
  65                  * Sneaky, corrupted BARs... but not with us!
  66                  */
  67
  68                 return ;
  69         }
  70
  71         bar = (void *) hdr;
  72
  73         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
  74             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
  75                 /* not implemented yet */
  76
  77                 return ;
  78         }
  79
  80         ctx = wlan_get_bar_cache_buffer();
  81
  82         memcpy(ctx->ra, bar->ra, 6);
  83         memcpy(ctx->ta, bar->ta, 6);
  84         ctx->control = bar->control;
  85         ctx->start_seq_num = bar->start_seq_num;
  86 }
  87
  88 static unsigned int wlan_rx_filter(struct dma_desc *desc)
  89 {
  90         struct ieee80211_hdr *hdr;
  91         unsigned int data_len;
  92         unsigned int rx_filter;
  93         unsigned int mac_err;
  94
  95         data_len = ar9170_get_rx_mpdu_len(desc);
  96         mac_err = ar9170_get_rx_macstatus_error(desc);
  97
  98 #define AR9170_RX_ERROR_BAD (AR9170_RX_ERROR_FCS | AR9170_RX_ERROR_PLCP)
  99
 100         if (unlikely(data_len < (4 + 6 + FCS_LEN) ||
 101             desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN) ||
 102             mac_err & AR9170_RX_ERROR_BAD) {
 103                 /*
 104                  * This frame is too damaged to do anything
 105                  * useful with it.
 106                  */
 107
 108                 return CARL9170_RX_FILTER_BAD;
 109         }
 110
 111         rx_filter = 0;
 112         if (mac_err & AR9170_RX_ERROR_WRONG_RA)
 113                 rx_filter |= CARL9170_RX_FILTER_OTHER_RA;
 114
 115         if (mac_err & AR9170_RX_ERROR_DECRYPT)
 116                 rx_filter |= CARL9170_RX_FILTER_DECRY_FAIL;
 117
 118         hdr = ar9170_get_rx_i3e(desc);
 119         if (likely(ieee80211_is_data(hdr->frame_control))) {
 120                 rx_filter |= CARL9170_RX_FILTER_DATA;
 121         } else if (ieee80211_is_ctl(hdr->frame_control)) {
 122                 switch (le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE) {
 123                 case IEEE80211_STYPE_BACK_REQ:
 124                         handle_bar(desc, hdr, data_len, mac_err);
 125                         rx_filter |= CARL9170_RX_FILTER_CTL_BACKR;
 126                         break;
 127                 case IEEE80211_STYPE_PSPOLL:
 128                         rx_filter |= CARL9170_RX_FILTER_CTL_PSPOLL;
 129                         break;
 130                 case IEEE80211_STYPE_BACK:
 131                         if (fw.wlan.queued_bar) {
 132                                 /*
 133                                  * Don't filter block acks when the application
 134                                  * has queued BARs. This is because the firmware
 135                                  * can't do the accouting and the application
 136                                  * has to sort out if the BA belongs to any BARs.
 137                                  */
 138                                 break;
 139                         }
 140                         /* fall through */
 141                 default:
 142                         rx_filter |= CARL9170_RX_FILTER_CTL_OTHER;
 143                         break;
 144                 }
 145         } else {
 146                 /* ieee80211_is_mgmt */
 147                 rx_filter |= CARL9170_RX_FILTER_MGMT;
 148         }
 149
 150         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 151                 wol_rx(rx_filter, hdr, min(data_len,
 152                         (unsigned int)AR9170_BLOCK_SIZE));
 153         }
 154
 155 #undef AR9170_RX_ERROR_BAD
 156
 157         return rx_filter;
 158 }
 159
 160 void handle_wlan_rx(void)
 161 {
 162         struct dma_desc *desc;
 163
 164         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 165                 if (!(wlan_rx_filter(desc) & fw.wlan.rx_filter)) {
 166                         dma_put(&fw.pta.up_queue, desc);
 167                         up_trigger();
 168                 } else {
 169                         dma_reclaim(&fw.wlan.rx_queue, desc);
 170                         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 171                 }
 172         }
 173 }