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authorroot <root@artemis.panaceas.org>2015-12-25 15:00:15 +0000
committerroot <root@artemis.panaceas.org>2015-12-25 15:00:15 +0000
commitddd86436f4e3643c04b797f858dab95d5f2e4de9 (patch)
treebfe7a780cf9a2f4fc33aec32c82e625e79dece1f /drivers/net/wireless/iwlwifi/mvm/rx.c
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Diffstat (limited to 'drivers/net/wireless/iwlwifi/mvm/rx.c')
-rw-r--r--drivers/net/wireless/iwlwifi/mvm/rx.c365
1 files changed, 365 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/mvm/rx.c b/drivers/net/wireless/iwlwifi/mvm/rx.c
new file mode 100644
index 0000000..4dfc21a
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/mvm/rx.c
@@ -0,0 +1,365 @@
+/******************************************************************************
+ *
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called COPYING.
+ *
+ * Contact Information:
+ * Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *****************************************************************************/
+#include "iwl-trans.h"
+
+#include "mvm.h"
+#include "fw-api.h"
+
+/*
+ * iwl_mvm_rx_rx_phy_cmd - REPLY_RX_PHY_CMD handler
+ *
+ * Copies the phy information in mvm->last_phy_info, it will be used when the
+ * actual data will come from the fw in the next packet.
+ */
+int iwl_mvm_rx_rx_phy_cmd(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
+ struct iwl_device_cmd *cmd)
+{
+ struct iwl_rx_packet *pkt = rxb_addr(rxb);
+
+ memcpy(&mvm->last_phy_info, pkt->data, sizeof(mvm->last_phy_info));
+ mvm->ampdu_ref++;
+ return 0;
+}
+
+/*
+ * iwl_mvm_pass_packet_to_mac80211 - builds the packet for mac80211
+ *
+ * Adds the rxb to a new skb and give it to mac80211
+ */
+static void iwl_mvm_pass_packet_to_mac80211(struct iwl_mvm *mvm,
+ struct ieee80211_hdr *hdr, u16 len,
+ u32 ampdu_status,
+ struct iwl_rx_cmd_buffer *rxb,
+ struct ieee80211_rx_status *stats)
+{
+ struct sk_buff *skb;
+ unsigned int hdrlen, fraglen;
+
+ /* Dont use dev_alloc_skb(), we'll have enough headroom once
+ * ieee80211_hdr pulled.
+ */
+ skb = alloc_skb(128, GFP_ATOMIC);
+ if (!skb) {
+ IWL_ERR(mvm, "alloc_skb failed\n");
+ return;
+ }
+ /* If frame is small enough to fit in skb->head, pull it completely.
+ * If not, only pull ieee80211_hdr so that splice() or TCP coalesce
+ * are more efficient.
+ */
+ hdrlen = (len <= skb_tailroom(skb)) ? len : sizeof(*hdr);
+
+ memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
+ fraglen = len - hdrlen;
+
+ if (fraglen) {
+ int offset = (void *)hdr + hdrlen -
+ rxb_addr(rxb) + rxb_offset(rxb);
+
+ skb_add_rx_frag(skb, 0, rxb_steal_page(rxb), offset,
+ fraglen, rxb->truesize);
+ }
+
+ memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
+
+ ieee80211_rx_ni(mvm->hw, skb);
+}
+
+/*
+ * iwl_mvm_calc_rssi - calculate the rssi in dBm
+ * @phy_info: the phy information for the coming packet
+ */
+static int iwl_mvm_calc_rssi(struct iwl_mvm *mvm,
+ struct iwl_rx_phy_info *phy_info)
+{
+ int rssi_a, rssi_b, rssi_a_dbm, rssi_b_dbm, max_rssi_dbm;
+ int rssi_all_band_a, rssi_all_band_b;
+ u32 agc_a, agc_b, max_agc;
+ u32 val;
+
+ /* Find max rssi among 2 possible receivers.
+ * These values are measured by the Digital Signal Processor (DSP).
+ * They should stay fairly constant even as the signal strength varies,
+ * if the radio's Automatic Gain Control (AGC) is working right.
+ * AGC value (see below) will provide the "interesting" info.
+ */
+ val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]);
+ agc_a = (val & IWL_OFDM_AGC_A_MSK) >> IWL_OFDM_AGC_A_POS;
+ agc_b = (val & IWL_OFDM_AGC_B_MSK) >> IWL_OFDM_AGC_B_POS;
+ max_agc = max_t(u32, agc_a, agc_b);
+
+ val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_AB_IDX]);
+ rssi_a = (val & IWL_OFDM_RSSI_INBAND_A_MSK) >> IWL_OFDM_RSSI_A_POS;
+ rssi_b = (val & IWL_OFDM_RSSI_INBAND_B_MSK) >> IWL_OFDM_RSSI_B_POS;
+ rssi_all_band_a = (val & IWL_OFDM_RSSI_ALLBAND_A_MSK) >>
+ IWL_OFDM_RSSI_ALLBAND_A_POS;
+ rssi_all_band_b = (val & IWL_OFDM_RSSI_ALLBAND_B_MSK) >>
+ IWL_OFDM_RSSI_ALLBAND_B_POS;
+
+ /*
+ * dBm = rssi dB - agc dB - constant.
+ * Higher AGC (higher radio gain) means lower signal.
+ */
+ rssi_a_dbm = rssi_a - IWL_RSSI_OFFSET - agc_a;
+ rssi_b_dbm = rssi_b - IWL_RSSI_OFFSET - agc_b;
+ max_rssi_dbm = max_t(int, rssi_a_dbm, rssi_b_dbm);
+
+ IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d Max %d AGCA %d AGCB %d\n",
+ rssi_a_dbm, rssi_b_dbm, max_rssi_dbm, agc_a, agc_b);
+
+ return max_rssi_dbm;
+}
+
+/*
+ * iwl_mvm_set_mac80211_rx_flag - translate fw status to mac80211 format
+ * @mvm: the mvm object
+ * @hdr: 80211 header
+ * @stats: status in mac80211's format
+ * @rx_pkt_status: status coming from fw
+ *
+ * returns non 0 value if the packet should be dropped
+ */
+static u32 iwl_mvm_set_mac80211_rx_flag(struct iwl_mvm *mvm,
+ struct ieee80211_hdr *hdr,
+ struct ieee80211_rx_status *stats,
+ u32 rx_pkt_status)
+{
+ if (!ieee80211_has_protected(hdr->frame_control) ||
+ (rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
+ RX_MPDU_RES_STATUS_SEC_NO_ENC)
+ return 0;
+
+ /* packet was encrypted with unknown alg */
+ if ((rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
+ RX_MPDU_RES_STATUS_SEC_ENC_ERR)
+ return 0;
+
+ switch (rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) {
+ case RX_MPDU_RES_STATUS_SEC_CCM_ENC:
+ /* alg is CCM: check MIC only */
+ if (!(rx_pkt_status & RX_MPDU_RES_STATUS_MIC_OK))
+ return -1;
+
+ stats->flag |= RX_FLAG_DECRYPTED;
+ IWL_DEBUG_WEP(mvm, "hw decrypted CCMP successfully\n");
+ return 0;
+
+ case RX_MPDU_RES_STATUS_SEC_TKIP_ENC:
+ /* Don't drop the frame and decrypt it in SW */
+ if (!(rx_pkt_status & RX_MPDU_RES_STATUS_TTAK_OK))
+ return 0;
+ /* fall through if TTAK OK */
+
+ case RX_MPDU_RES_STATUS_SEC_WEP_ENC:
+ if (!(rx_pkt_status & RX_MPDU_RES_STATUS_ICV_OK))
+ return -1;
+
+ stats->flag |= RX_FLAG_DECRYPTED;
+ return 0;
+
+ default:
+ IWL_ERR(mvm, "Unhandled alg: 0x%x\n", rx_pkt_status);
+ }
+
+ return 0;
+}
+
+/*
+ * iwl_mvm_rx_rx_mpdu - REPLY_RX_MPDU_CMD handler
+ *
+ * Handles the actual data of the Rx packet from the fw
+ */
+int iwl_mvm_rx_rx_mpdu(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
+ struct iwl_device_cmd *cmd)
+{
+ struct ieee80211_hdr *hdr;
+ struct ieee80211_rx_status rx_status = {};
+ struct iwl_rx_packet *pkt = rxb_addr(rxb);
+ struct iwl_rx_phy_info *phy_info;
+ struct iwl_rx_mpdu_res_start *rx_res;
+ u32 len;
+ u32 ampdu_status;
+ u32 rate_n_flags;
+ u32 rx_pkt_status;
+
+ phy_info = &mvm->last_phy_info;
+ rx_res = (struct iwl_rx_mpdu_res_start *)pkt->data;
+ hdr = (struct ieee80211_hdr *)(pkt->data + sizeof(*rx_res));
+ len = le16_to_cpu(rx_res->byte_count);
+ rx_pkt_status = le32_to_cpup((__le32 *)
+ (pkt->data + sizeof(*rx_res) + len));
+
+ memset(&rx_status, 0, sizeof(rx_status));
+
+ /*
+ * drop the packet if it has failed being decrypted by HW
+ */
+ if (iwl_mvm_set_mac80211_rx_flag(mvm, hdr, &rx_status, rx_pkt_status)) {
+ IWL_DEBUG_DROP(mvm, "Bad decryption results 0x%08x\n",
+ rx_pkt_status);
+ return 0;
+ }
+
+ if ((unlikely(phy_info->cfg_phy_cnt > 20))) {
+ IWL_DEBUG_DROP(mvm, "dsp size out of range [0,20]: %d\n",
+ phy_info->cfg_phy_cnt);
+ return 0;
+ }
+
+ if (!(rx_pkt_status & RX_MPDU_RES_STATUS_CRC_OK) ||
+ !(rx_pkt_status & RX_MPDU_RES_STATUS_OVERRUN_OK)) {
+ IWL_DEBUG_RX(mvm, "Bad CRC or FIFO: 0x%08X.\n", rx_pkt_status);
+ return 0;
+ }
+
+ /* This will be used in several places later */
+ rate_n_flags = le32_to_cpu(phy_info->rate_n_flags);
+
+ /* rx_status carries information about the packet to mac80211 */
+ rx_status.mactime = le64_to_cpu(phy_info->timestamp);
+ rx_status.device_timestamp = le32_to_cpu(phy_info->system_timestamp);
+ rx_status.band =
+ (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_BAND_24)) ?
+ IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
+ rx_status.freq =
+ ieee80211_channel_to_frequency(le16_to_cpu(phy_info->channel),
+ rx_status.band);
+ /*
+ * TSF as indicated by the fw is at INA time, but mac80211 expects the
+ * TSF at the beginning of the MPDU.
+ */
+ /*rx_status.flag |= RX_FLAG_MACTIME_MPDU;*/
+
+ /* Find max signal strength (dBm) among 3 antenna/receiver chains */
+ rx_status.signal = iwl_mvm_calc_rssi(mvm, phy_info);
+
+ IWL_DEBUG_STATS_LIMIT(mvm, "Rssi %d, TSF %llu\n", rx_status.signal,
+ (unsigned long long)rx_status.mactime);
+
+ /*
+ * "antenna number"
+ *
+ * It seems that the antenna field in the phy flags value
+ * is actually a bit field. This is undefined by radiotap,
+ * it wants an actual antenna number but I always get "7"
+ * for most legacy frames I receive indicating that the
+ * same frame was received on all three RX chains.
+ *
+ * I think this field should be removed in favor of a
+ * new 802.11n radiotap field "RX chains" that is defined
+ * as a bitmask.
+ */
+ rx_status.antenna = (le16_to_cpu(phy_info->phy_flags) &
+ RX_RES_PHY_FLAGS_ANTENNA)
+ >> RX_RES_PHY_FLAGS_ANTENNA_POS;
+
+ /* set the preamble flag if appropriate */
+ if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_SHORT_PREAMBLE))
+ rx_status.flag |= RX_FLAG_SHORTPRE;
+
+ if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_AGG)) {
+ /*
+ * We know which subframes of an A-MPDU belong
+ * together since we get a single PHY response
+ * from the firmware for all of them
+ */
+ rx_status.flag |= RX_FLAG_AMPDU_DETAILS;
+ rx_status.ampdu_reference = mvm->ampdu_ref;
+ }
+
+ /* Set up the HT phy flags */
+ switch (rate_n_flags & RATE_MCS_CHAN_WIDTH_MSK) {
+ case RATE_MCS_CHAN_WIDTH_20:
+ break;
+ case RATE_MCS_CHAN_WIDTH_40:
+ rx_status.flag |= RX_FLAG_40MHZ;
+ break;
+ case RATE_MCS_CHAN_WIDTH_80:
+ rx_status.flag |= RX_FLAG_80MHZ;
+ break;
+ case RATE_MCS_CHAN_WIDTH_160:
+ rx_status.flag |= RX_FLAG_160MHZ;
+ break;
+ }
+ if (rate_n_flags & RATE_MCS_SGI_MSK)
+ rx_status.flag |= RX_FLAG_SHORT_GI;
+ if (rate_n_flags & RATE_HT_MCS_GF_MSK)
+ rx_status.flag |= RX_FLAG_HT_GF;
+ if (rate_n_flags & RATE_MCS_HT_MSK) {
+ rx_status.flag |= RX_FLAG_HT;
+ rx_status.rate_idx = rate_n_flags & RATE_HT_MCS_INDEX_MSK;
+ } else if (rate_n_flags & RATE_MCS_VHT_MSK) {
+ rx_status.vht_nss =
+ ((rate_n_flags & RATE_VHT_MCS_NSS_MSK) >>
+ RATE_VHT_MCS_NSS_POS) + 1;
+ rx_status.rate_idx = rate_n_flags & RATE_VHT_MCS_RATE_CODE_MSK;
+ rx_status.flag |= RX_FLAG_VHT;
+ } else {
+ rx_status.rate_idx =
+ iwl_mvm_legacy_rate_to_mac80211_idx(rate_n_flags,
+ rx_status.band);
+ }
+
+ iwl_mvm_pass_packet_to_mac80211(mvm, hdr, len, ampdu_status,
+ rxb, &rx_status);
+ return 0;
+}